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Re: [Boost-users] How to write a block-wise filter...
by EMalenfant＠interstarinc.com 18 May '06

18 May '06

Hi Stephen, From: Stephen Webb [mailto:swebb75ky@gmail.com] > My trouble is > knowing when the end-of-input has arrived. Is there a well > defined way that my output filter is notified of a close > event or something similar? I did see close functions > defined in the example filters, but mine isn't getting > called. Is you filter's category convertible to "closable_tag"? A filter's category has to be tagged as "closable" for its close function to be called: http://www.boost.org/libs/iostreams/doc/index.html?path=4.1.3.1 HTH, Éric

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[program_options] Positional options doc/bug in add()
by Ian McCulloch 18 May '06

18 May '06

Hi, Following the example from program_options/overview.html, I tried positional_options_description pd; pd.add("output-file", 2).add_optional("input-file", -1); This doesn't work: positional_options_description::add() returns 'void', and add_optional() is probably a typo for add() ? Currently, the only way to get this to work seems to be positional_options_description pd; pd.add("output-file", 2); pd.add("input-file", -1); But following the style of the rest of the library, I expect it was intended that positional_options_description::add() would return a reference to *this ? Using boost 1.33.1, the CVS version of positional_options.hpp is unchanged. Cheers, Ian McCulloch

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Exposing Class with Private ctor and dtor
by Anand, Kumar 18 May '06

18 May '06

Hi, A class has static method to create and a static method to destroy. And the constructors and destructor of the class is marked as private. How do I expose such a class in Python? Eg. class A { private: static A* instance; A() { }; ~A {}; public: static A* create () { If(instance != 0) instance = new A(); return instance; } static void destroy() { delete instance; instance = 0; } }; In Boost Python, I tried the following but the code doesn't compile unless I make the destructor of class A as public. namespace bp = boost::python; bp::class_<A> ("A", bp::no_init) .def("create", &A::create) .def("destroy", &A::destroy) .staticmethod("create") .staticmethod("destroy") ; Any suggestions? Thanks Kumar

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[boost-users]how to use iostreams::mapped_file
by Sunil Kumar N 18 May '06

18 May '06

Could someone point me to a link for a sample program of using iostreams::mapped_file(except the default tutorial)...I gave a shot at it and snippet is as follows... io::mapped_file_params aparams("c:\\mf.txt"); aparams.new_file_size = 1e8; aparams.mode = BOOST_IOS::out; io::stream_buffer<io::mapped_file> mfStrmBuf(aparams); ostream out(&mfStrmBuf); out << .... keep on writing to file... it works but I need to know how one create a mapped_file that has to grow beyond new_file_size!! That means I dont know the size of the file to be created at compile time!! How to flush explicitly? I am in the process of understanding as to which one offers better performance with respect to time taken when some thousands of lines have to be written to a file.....ofstream vs mapped_file? Thanks in advance :)

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How to write a block-wise filter...
by Stephen Webb 17 May '06

17 May '06

I don't really have my head around the Boost IO filter architecture yet, but I have managed to get a very basic filter working. I'm having some trouble with end-of-input issues. I think what I'm trying to do comes up frequently, so hopefully this will be a straightforward answer... What I'm trying to do is write a filter that takes in input one character at a time (for simplicity -- for now), and outputs encrypted characters. The block size is 4 bytes, so every 4 characters I can encrypt, and then spit out the result. If I hit the end of input, then I want to pad the plaintext, encrypt and output the final block. My trouble is knowing when the end-of-input has arrived. Is there a well defined way that my output filter is notified of a close event or something similar? I did see close functions defined in the example filters, but mine isn't getting called. I tried to look at the base64 encode/decode headers (which would have to deal with the same issue) but I couldn't really follow it. Any help is appreciated. Thanks -Steve

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Re: [Boost-users] [date_time] Need help with a couple simple problems
by Scott 17 May '06

17 May '06

> #include "boost/date_time/local_time_adjustor.hpp" > #include "boost/date_time/c_local_time_adjustor.hpp" > > ptime local_var > =date_time::c_local_adjustor<ptime>::utc_to_local(utc_var); > > What do you mean by the file is in binary format? Thanks for the help. What I mean is I would like to read/write the value of the ptime in the most efficient way possible. So if the ptime is stored as 2 ints, I would like to (de)serialize 8 bytes (4 bytes each int). Portability isn't an issue. What I would rather *not* do is use something like to_iso_string(ptime) and from_iso_string(ptime). The string representation is rather long. But if that's the only way to do it, guess I'll have to make do. Thanks, Scott

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[multi_array] Useful algorithms (from Re: Multi_array: A "proper" iterator over a N>1 Multi_array?)
by Beth Jacobson 17 May '06

17 May '06

On a recent thread, Bruno Martinez provided a std::for_each-like function for multi_arrays which lets users apply a function to each element in a multi_array or view without having to know anything about the dimensions. I've been playing around with it (on MSVC 7.1) and it works perfectly. It seems like a good utility for anyone using boost.multi_array. Working from Bruno's code, I wrote a similar std::accumulate-like function, which could also be generally useful. I'm fairly new to template programming, so if someone could look over the code below and see if I've done something dangerous or stupid, it would be much appreciated. Also, is there some standard Boost way of making this sort of code generally available? It probably isn't at a level where it could be included in the library, but it seems like a shame to just let it languish in the bowels of the mailing list archive. Anyway, here are both algorithms: My accumulate-like function: template<class MA, class T, class F, int dim> struct accum_impl { F f; T &val; accum_impl(T &val, F f) : f(f), val(val) {} T operator()(MA& ma) { std::for_each(ma.begin(), ma.end(), accum_impl<typename boost::add_const<MA::const_reference>::type, T, F, dim-1>(val, f)); return val; } }; template<class Ref, class T, class F> struct accum_impl<Ref, T, F, 0> { F f; T &val; accum_impl(T &val, F &f) : f(f), val(val) {} T operator()(Ref r) { val = f(val, r); return val; } }; template<class MA, class T, class F> T multi_accum(MA& ma, T init, F f) { accum_impl<MA, T, F, MA::dimensionality> impl(init, f); return impl(ma); } And a test: typedef boost::multi_array<int, 3> array_type; typedef array_type::index_range range; typedef array_type::index index; array_type B(boost::extents[4][2][3]); int values = 0; for(index i = 0; i != 4; ++i) for(index j = 0; j != 2; ++j) for(index k = 0; k != 3; ++k) B[i][j][k] = values++; array_type::array_view<2>::type myview = B[ boost::indices[range(1,3)][1][range(0,2)] ]; cout << "Sum: " << multi_accum(myview, 0, std::plus<int>()) << endl; cout << "Product: " << multi_accum(myview, 1, std::multiplies<int>()) << endl; Bruno Martinez's for_each-like function: template<class MA, class F, int dim> struct for_each_impl { F f; for_each_impl(F f) : f(f) {} void operator()(MA& ma) { std::for_each(ma.begin(), ma.end(), for_each_impl<typename MA::reference, F, dim-1>(f)); } }; template<class Ref, class F> struct for_each_impl<Ref, F, 0> { F f; for_each_impl(F f) : f(f) {} void operator()(Ref r) { f(r); } }; template<class MA, class F> void multi_for_each(MA& ma, F f) { for_each_impl<MA, F, MA::dimensionality> impl(f); impl(ma); } And a test: typedef boost::multi_array<double, 3> array_type; typedef array_type::index index; array_type myarray(boost::extents[3][4][2]); typedef array_type::index_range range; array_type::array_view<3>::type myview = myarray[ boost::indices[range(0,2)][range(1,3)][range(0,4,2)] ]; multi_for_each(myview, _1 = 56);

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How to link (properly)
by Jason House 17 May '06

17 May '06

When I run bjam install on my laptop running Mandriva 2006, it places a lot of files in /usr/local/lib with names like libboost_XXX-gcc.a While I know that I can pass -lboost_XXX-gcc and it links, the -gcc bit seems to make things a bit too platform dependent for my liking. What's the proper way to handle that extra bit at the end of the library name? The project I'm working on uses autoconf/configure/make as its build environment.

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Regex Localization problem
by Antonio Scotti 17 May '06

17 May '06

Hi, I have a portability problem with regex (probably due to localization issues). I've found that, under Win32, the regular expression "\w" matches all the alphanumeric chars, including non ascii ones (such as e grave or e acute). This doesn't hold while under linux. In fact, \w only seems to match ascii characters. I've tried chancing the locale, but nothing changed. Is there a way to make \w have on linux the same behaviour it has on win32? Thanks in advance.

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newbie boost::random how can I get a variate_generator for uniform_01 distribution?
by wave style 17 May '06

17 May '06

Hi, I have some strange behavior on win XP with VC 8.0 version and boost::random library. When I use variate_generator helper template with uniform_01 distribution, I always get an compiler error. like as: //code boost::mt19937 rng(time(0)); boost::uniform_01<mt19937> u01(rng); boost::variate_generator<mt19937, uniform_01<mt19937> > die401(rng, u01); //compile info error C2039: 'input_type' : is not a member of 'boost::uniform_01<UniformRandomNumberGenerator>' with [ UniformRandomNumberGenerator=boost::mt19937 ] f:\my documents\visual studio 2005\projects\testboost\testrandom\testrandom.cpp(169) : see reference to class template instantiation 'boost::variate_generator<Engine,Distribution>' being compiled with [ Engine=boost::mt19937, Distribution=boost::uniform_01<boost::mt19937> ] Actually, the uniform_01 class doesn't declare a type named input_type in uniform_01.hpp, because uniform_01 distribution can accept both IntegerType and RealType UniformRandomGenerator. It seems that variate_generator can not support the uniform_01. However, I found the engine_helper struct be specialized for uniform_01 and uniform_int_float in variate_generator.hpp. I got confused. It's vc8.0compiler's bug? How can I get a variate_generator for uniform_01 distribution? Any feedback welcomed!! Thanks. Waveform.

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[boost-build] telling one project to depend on another
by Brian Budge 17 May '06

17 May '06

Hi all - I'm trying out boost-build for the first time, and running into some issues related to project dependencies. I've spent many hours looking at boost-build documentation, and now I'm stuck. My directory structure is laid out like this: -------------------------------------------- base_dir Jamroot simp_envelopes Jamfile ***source*** simp_envelopes ***include files*** my_lib Jamfile ***source*** include ***include files*** test Jamfile tester.cc --------------------------------------------- Basically, my_lib depends on simp_envelopes and test depends on my_lib. In simp_envelopes/Jamfile I have this: ------------ project simplify-libs : usage-requirements <include>simp_envelopes ; lib simplify : [ glob *.cc ] : <include>simp_envelopes ; ------------ which I believe should tell my_libs to include simp_envelopes/simp_envelopes, if only my_libs can know that it should depend on the simp_envelopes project. My Jamroot looks like: ------------ use-project simplify-libs : simp_envelopes ; use-project my-libs : my_libs ; project my_app : requirements <include>.. <include>../SGUL/include : default-build debug ; lib open-mesh : : <file>../OpenMesh/Core/Linux_gcc_max/libOpenMesh_Core.so ; build-project simp_envelopes ; build-project my_libs ; build-project test ; ------------ My my_libs Jamfile: ------------ project my_libs : requirements <include>../simp_envelopes : usage-requirements <include>include ; lib my_libs : [ glob *.cc ] /simplify-libs//simplify : <include>include ; ------------- I had to add the requirements <include>../simp_envelopes for my_libs to find the include files for simp_envelopes... is there a way to get my_libs to depend on simp_envelopes (or simplify-libs) and take care of this automatically? I have similar issues for the test app... I need to at a requirements for the my_libs include directory. Finally, I have defined a library name open-mesh to point to my external library, but I don't know how to have my my_libs essentially require linking against open-mesh. This is in fact even more important because I don't currently have a way of making my application build rule depend on open-mesh. Any help is appreciated! Brian

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[Thread] Get current thread id
by marie-line.gentil2 17 May '06

17 May '06

Is there a boost method which does it? I went through the whole thread documention but could not figure out how to do so.

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assert.h
by dvir schirman 16 May '06

16 May '06

Hi I try to use the random library in order to create a noise signal with normal distribution. I'm using Cygwin platform, and I'm using g++ compiler. I wrote: #include <boost/random.hpp> at the beginning of my header file. and when I tried to compile I got the following error message: In file included from /usr/lib/gcc/i686-pc-cygwin/3.4.4/include/c++/cassert:48, from ../boost/boost/random/linear_congruential.hpp:20, from ../boost/boost/random.hpp:36, from actor.H:12, from tdagent.H:11, from main.C:1: /usr/include/assert.h:6: error: expected unqualified-id before string constant /usr/include/assert.h:6: error: expected `,' or `;' before string constant main.C, tdagent.H, actor.H are files that I've written. I am not familiar with assert.h, I guess it's part of the c++ headers, and that there shouldn't be an error in it. Hope someone can help me solve it. Dvir.

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Re: [Boost-users] newbie - boost::shared_ptr of type stringstream using << operator?
by james.jones＠firstinvestors.com 16 May '06

16 May '06

From: Ed Johnson <ed(a)edwardotis.com> > Hi Eric, > > I tried and none of the following modes worked. > >boost::shared_ptr< std::stringstream > sharedStream(new >std::stringstream("hello world", std::stringstream::out | >std::stringstream::ate )); [other examples snipped] Ed, I think you should prove this isn't a boost::shared_ptr issue first. Have you tried it with a raw pointer? I suspect you'll get the exact same results as with boost::shared_ptr, which would indicate a problem with your implementation of std::stringstream, not with boost::shared_ptr. Your prior example was this: > std::stringstream tr; > tr << "hello everyone"; > tr << "!"; > std::cerr << tr.str() << std::endl; But this is a different call pattern, not just a change from an object to a smart pointer. This probably works fine: boost::shared_ptr<std::stringstream> tr(new std::stringstream()); (*tr) << "hello, world"; (*tr) << "!"; std::cerr << tr->str() << std::endl; And this probably doesn't work: std::stringstream tr("hello, world", std::stringstream::out | std::stringstream::ate); tr << "!"; std::cerr << tr.str() << std::endl; If I'm right in both cases, your problem is with std::stringstream, not with boost::shared_ptr. Regards, - James Jones Administrative Data Mgmt. Webmaster 375 Raritan Center Pkwy, Suite A Data Architect Edison, NJ 08837

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Re: [Boost-users] [review] Boost.Fusion
by David Abrahams 16 May '06

16 May '06

Joel de Guzman <joel(a)boost-consulting.com> writes: >> It will catch up :-) On a side note, it seems the tests were run with >> gcc 3.4. IIRC, gcc 4 and beyond introduced a couple of interesting >> optimizations so I wonder how far do those go towards narrowing the gap. > > I would love to see better numbers for g++. Building a later G++ under cygwin is pretty easy if you know what to do. That's how I stay abreast of G++ developments. -- Dave Abrahams Boost Consulting www.boost-consulting.com

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boost::shared_ptr typedef drives me crazy
by Ovanes Markarian 16 May '06

16 May '06

I have some strange behavior on RH Enterprise Linux 2.6.9-34 with gcc (GCC) 3.2.3 version and boost::shared_ptr template. The thning which drives me crazy compiles for one library without any problems and for the other library it can't compile one of my typedefs. Maybe some of you have had the similar problem before. Here some snippet: I have some really simple type traits definitions: template <class T> struct traits_internal { typedef T type; typedef T& ref; typedef T* ptr; typedef const T* const_ptr; typedef const T& const_ref; typedef const T const_type; }; template <class T> struct traits : traits_internal<T> {}; template <class T> struct traits<T*> : traits_internal<T> {}; template <class T> struct traits<T&> : traits_internal<T> {}; then I have a factory class, which can creates an empty class instance, copies the instance from another instance or copies it from the underlying POD (raw data). template<class Type_, class Raw_, class MemMan_> struct Creator { public: typedef typename msg_factory::traits<Type_>::type val_type; typedef typename msg_factory::traits<Type_ >::const_type const_type; typedef typename msg_factory::traits<Raw_>::type raw_type; typedef typename msg_factory::traits<MemMan_>::type man_type; typedef boost::shared_ptr<val_type> smart_ptr; typedef boost::shared_ptr<const_type> const_smart_ptr; private: /** * a union container which decides which member to use, POD or Class * used to save space required by 2 pointers */ typedef msg_factory::PointerContainer<val_type, raw_type> ptr_container; typedef Creator<Type_, Raw_, MemMan_> my_type; public: inline explicit Creator(man_type* m = NULL) : memMan(m), copy_from(static_cast<val_type*>(NULL)){} inline explicit Creator(const raw_type* s, man_type* m = NULL) : memMan(m), copy_from(s) {} inline explicit Creator(const val_type& t, man_type* m = NULL) : memMan(m), copy_from(&t) {} inline ~Creator(){} inline operator smart_ptr()const { return smart_ptr((copy_from.is_valid()?(copy_from.first()?(new val_type(*copy_from.first(), memMan)):(new val_type(copy_from.second(), memMan))):(new val_type(memMan)))); } private: inline Creator(const my_type&) {} inline my_type& operator=(const my_type&) {return *this;} template <class OtherType_, class OtherRaw_, class OtherMemMan_> inline Creator(const Creator<OtherType_, OtherRaw_, OtherMemMan_>&) {} template <class OtherType_, class OtherRaw_, class OtherMemMan_> inline Creator& operator =(const Creator<OtherType_, OtherRaw_, OtherMemMan_>&) {return *this;} man_type* memMan; ptr_container copy_from; }; class ClassB : public ClassA { public: typedef Creator<ClassB, POD_B, ClassA> heap_instance; typedef heap_instance::smart_ptr smart_ptr; -->typedef heap_instance::const_smart_ptr const_smart_ptr; private: friend class Creator<ClassB, POD_B, ClassA>; explicit ClassB(ClassA *pcDataManager = NULL); explicit ClassB(const POD_B *ptCopyFromPOD, ClassA *pcDataManager = NULL); explicit ClassB(const ClassB &copyFromOtherClassB, ClassA *pcDataManager = NULL); //some class data follows } In this line compiler raises the error: ISO C++ forbids declaration of `const_smart_ptr' with no type /some/path/here/fname:lineno: cannot declare member ` Creator<ClassB, POD_B, ClassA>::const_smart_ptr' within `ClassB' /some/path/here/fname:lineno: syntax error before `;' token *** Error code 1 Somehow it does not know the type, even if I try in Creator to change the typedef from: typedef boost::shared_ptr<const_type> const_smart_ptr; to typedef boost::shared_ptr<val_type> const_smart_ptr; I still get an error at this line. And the most weired thing is, why it can compile a line before?! Where typedef boost::shared_ptr<val_type> smart_ptr; is used as forward declaration? I also tried in the Creator to change typedef boost::shared_ptr<const_type> const_smart_ptr; to typedef smart_ptr const_smart_ptr; And compiler was able to compile it... Do you have any suggestions? I am using boost 1.33_0 Many thanks, Ovanes Markarian

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Re: [Boost-users] newbie - boost::shared_ptr of type stringstreamusing << operator?
by Andrew McDonald 16 May '06

16 May '06

The stringstream (or ostringstream) stringstream ss("Hello", ios_base::out); will create a stringstream with the output sequence initialised to "Hello" and the position set to the _beginning_ of the sequence. Thus any insertions will overwrite the value from the initialiser string. There were various issues and debates after the 1998 standard came out [Issues 432 and Issue 45 (closed)]..and it is a little unclear to me what the resolution was...but I _think_ the following is correct... - The standard does not mandate that ostringstream (more precisely the underlying stringbuf) supports ios_base::ate. - However, many implementations do support it. As an arbitrary test, compiling with Visual Express 2005 and using ios_base::ate, I find that this does move the position to the end of the sequence. Note that stringstreams must support explicitly seeking to the end of the sequence; e.g. ostringstream oss("Hello"); oss.seekp(o, ios_base::end); oss << " world"; regards, Andrew McDonald System Architect Norwood Systems Australia Pty Ltd Level 1, 71 Troy Terrace PO Box 1281 Subiaco, WA 6904 Tel +61 8 9380 7766 Fax +61 8 9380 7733 andrew.mcdonald(a)norwoodsystems.com The information in this email, and any attachments, may contain confidential information and is intended solely for the attention and use of the named addressee (s). It must not be disclosed to any person(s) without authorization. If you are not the intended recipient, or a person responsible for delivering it to the intended recipient, you are not authorized to, and must not, disclose, copy, distribute, or retain this message or any part of it. If you have received this communication in error, please notify the sender immediately.

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Re: [Boost-users] [review] Boost.Fusion
by João Abecasis 16 May '06

16 May '06

Joel de Guzman wrote: > João Abecasis wrote: >> On the directory structure used for the headers, I like the modular >> approach but sometimes get the feeling that it's too fragmented. Having >> more top-level reflections of individual components would ease my >> concerns. Another aspect is that this structure diverges from what is >> used in MPL. Given the parallel between the two libraries I think an >> effort should be made to keep the structure similar. In fact, this is >> also part of the user interface. Still, in the end, I recognize that >> they're two independent libraries and must each follow its path. > > Understood. I'll give this a lot of thinking. At the very least, > we'll surely have a flat set of headers that forward to the > main headers. Where to place them is a matter to deliberate on. > Maybe <boost/fusion/hdr/xxx.hpp> ? or simply <boost/fusion/xxx.hpp> > and push the main tree downwards in another directory, say, "main"? Why do you need to have them in separate directories? Are there conflicting/overlaping headers when you mix the approaches (or are you just trying to keep everything nice and tidy ;-) ) ? >> Fusion is coded with the expectation that the library code will be >> optimized into very tight code, which seems to be a reasonable >> assumption with (any?) modern compilers. > > I hope g++ will catch up! See Dan's post regarding some Fusion > speed tests. g++ produces the fattest and slowest code :( > I wish I was using incorrect flags or I haven't found the > best compiler switches to use for g++. It will catch up :-) On a side note, it seems the tests were run with gcc 3.4. IIRC, gcc 4 and beyond introduced a couple of interesting optimizations so I wonder how far do those go towards narrowing the gap. > MS VC8.0 produces the tightest and fastest code, so far. > (No, I'm not a fan of MS. Those are just the facts.) Of course ;-) I like facts! From my limited experience, I've also seen MSVC produce the tightest code. Perhaps there should be a way to extract some benchmarks (e.g., code size, performance) from the Boost regression tests, or separate benchmark-tests for the different compilers could be integrated into the system. This could be interesting and useful information for library developers. >>> - What is your evaluation of the potential usefulness of the library? >> I believe Fusion has great potential as a library building block but >> also as a more application-oriented library. On the library building >> block side, I believe it has the potential to become a fundamental/core >> piece of Boost. For application developers, Fusion takes tuples to a new >> level, allowing one to make the most of information that is available at >> compile-time. I wanted to make an additional suggestion that might make Fusion's usefulness more visible, but it slipped my mind at the last minute. While I'm not that familiar with Boost.Serialization it seems to be a fairly popular library with developers of varying technical level. My suggestion is that Fusion Sequences be made serializable, using Boost.Serialization. This would go in a separate header (e.g., in fusion/sequence/io/serialization.hpp) and have the requirement that serialization be implemented for individual element types. If possible, the serialization would be generic, i.e., tied to the type sequence and not to the particular Fusion Sequence. With serialization in place, Fusion sequences could be used to manage a class's data and its serialization or they could be used as a proxy during serialization: archive & tie(a, b, c); Hmm... I see that the Quick Start mentions serialization as an example. Is there a reason for not offering the interface to Boost.Serialization in the library? Best regards, João

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[boost-users][serialization]Can I serialize wstring into text_oarchive?
by Wang Yun 16 May '06

16 May '06

Hi, all I do some tests and found it's ok to save/load wstring into/from text_oarchive, Am I very lucky? or it's safe to do this? When do I need to use text_woarchive? Thanks, Wang Yun

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Re: [Boost-users] newbie - boost::shared_ptr of type stringstream using << operator?
by EMalenfant＠interstarinc.com 15 May '06

15 May '06

From: Ed Johnson [mailto:ed@edwardotis.com] > > Thanks, I see where I was not using the correct constructor before. > However, even when I use the proper one, I get the same > results. I cannot get the '<<' operator to append to the > original string that I pass using the stringstream > constructor. It still begins at the first character and > begins overwriting the string. > > //constructor syntax > explicit stringstream ( openmode mode = in | out ); explicit > stringstream ( const string & str, openmode mode = in | out ); > > //updated code > boost::shared_ptr< std::stringstream > sharedStream(new > > std::stringstream("hello world", std::stringstream::out)); > > Is there something else I'm missing? > I think you have to use the "ate" or "app" openmode for that. HTH, Éric

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newbie - boost::shared_ptr of type stringstream using << operator?
by Ed Johnson 15 May '06

15 May '06

Hi, Is it possible to use shared_ptr to manage stringstreams, and still use the << operator on the stringstream? example: //I would like to print 'hello world!' in both cases #include <iostream> boost::shared_ptr< std::stringstream > sharedStream(new std::stringstream("hello world")); (*sharedStream) << "!"; std::cerr << (*sharedStream).str() << std::endl; std::stringstream tr; tr << "hello world"; tr << "!"; std::cerr << tr.str() << std::endl; output: !elloworld hello world! Many thanks, Ed Johnson

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ipp files
by Joe McCay 15 May '06

15 May '06

Simple question. What exactly are ipp files, and how are they used? jmccay

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Re: [Boost-users] [multi_index] thread safety
by Patel Priyank-PPATEL1 15 May '06

15 May '06

Thanks.. Let me try that out. Also, I will put check if mutex acquire method returns success or not during addition only than and than I will go ahead and add procedure in pool. Thanks Priyank ________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Kobi Cohen-Arazi Sent: Friday, May 12, 2006 11:33 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] thread safety Hi, comments below On 5/12/06, Patel Priyank-PPATEL1 <priyankpatel(a)motorola.com> wrote: Hi Joaquin, I have to use actually two or more threads on procedure pool. I start seeing same Problem when I have three/four threads working on same procedure pool. I tried to introduce mutex (ACE_Guard) but still having problems in execution in one/two minute of execution. Seems I am guarding every method that is used by container. Anything wrong with the Following code? int Procedure_Pool::add_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::add_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "ADDING %d\n", _procedure->id())); if (find_by_id(_procedure->id()) == 0) { ACE_Guard<ACE_Mutex> guard(mutex_); { // procedure not found procedure_by_id_.insert(_procedure); } // debug info ACE_DEBUG((LM_DEBUG, "Added procedure : %d \n", _procedure->id())); // return success return 0; } else { // error ACE_ERROR((LD_ERROR "%N:%l Error in adding procedure : %d \n", _procedure->id())); // return failure return -1; } } int Procedure_Pool::remove_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::remove_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "REMOVING: %d \n", _procedure->id())); if (find_by_id(_procedure->id()) != 0) { ACE_Guard<ACE_Mutex> guard(mutex_); { // procedure found procedure_by_id_.erase(_procedure->id()); } ACE_DEBUG((LM_DEBUG, "Removed procedure : %d \n", _procedure->id())); return 0; } else { ACE_ERROR((LD_ERROR "%N:%l Error in removing procedure : %d \n", _procedure->id())); return -1; } } Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_Guard<ACE_Mutex> guard(mutex_); { Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); return *it; } } ACE_DEBUG((LM_DEBUG, "%N:%l Not able to found procedure for id: %d \n", _id)); // return null return 0; } Yes. There is a small theoretical problem with your code. A possible race condition. you tried to find_by_id, using mutex, than release that mutex and reacquire it for erase. That's a possible race condition. The "find" until the "erase" must be atomic. At least IMHO. Kobi.

1 0

boost::iterator_adaptor
by Grisha Spivak 14 May '06

14 May '06

Hi, here is small code snippet to demonstrate my problrm: #include <stddef.h> #include <iostream> #include <boost/iterator/iterator_adaptor.hpp> template<typename T, size_t stride> class stride_iterator : public boost::iterator_adaptor<stride_iterator<T, stride>, T*> { public: stride_iterator() : stride_iterator::iterator_adaptor_( 0 ) { } explicit stride_iterator( T * p ) : stride_iterator::iterator_adaptor_( p ) { } private: friend class boost::iterator_core_access; void increment() { this->base_reference() = this->base() + stride; } void deccrement() { this->base_reference() = this->base() - stride; } void advance( ptrdiff_t d ) { this->base_reference() = this->base() + d*stride; } ptrdiff_t distance_to( stride_iterator const & i ) const { return ( i.base() - this->base() )/stride; } }; int main() { int arr[12] = {}; arr[3*2] = 33; arr[5*2] = 55; stride_iterator<int, 2> it( arr ); it[2] = -22; it[3] = it[5]; std::cout << arr[2*2] << ' ' << arr[3*2] << ' ' << arr[5*2] << '\n'; return 0; } It prints "-22 33 55" instead of "-22 55 55" (which I expected) - so "it[3] = it[5];" assignment didn't modifies array. Is it intended behaviour? Or maybe I'm doing something wrong?

3 3

newbie - boost::shared_ptr of type stringstream using << operator?
by Ed Johnson 14 May '06

14 May '06

Hi, Is it possible to use shared_ptr to manage stringstreams, and still use the << operator on the stringstream? example: #include <iostream> boost::shared_ptr< std::stringstream > sharedStream(new std::stringstream("hello world")); std::cerr << (*sharedStream).str() << std::endl; (*sharedStream) << "!"; std::cerr << (*sharedStream).str() << std::endl; std::stringstream tr; tr << "hello everyone"; tr << "!"; std::cerr << tr.str() << std::endl; output: hello world !elloworld hello everyone! Thanks, Ed Johnson

1 0

[review] Fusion review begins
by Ronald Garcia 14 May '06

14 May '06

The review of Joel de Guzman's Fusion library begins today, May 1, 2006, and continues through May 10, 2006. :Download: http://spirit.sourceforge.net/dl_more/fusion_v2.zip :Description: Fusion is a library of heterogenous containers and views and algorithms. A set of heterogenous containers (vector, list, set and map) is provided out of the box along with view classes that present various composable views over the data. The containers and views follow a common sequence concept with an underlying iterator concept that binds it all together, suitably making the algorithms fully generic over all sequence types. The architecture is somewhat modeled after MPL which in turn is modeled after STL. It is code-named "fusion" because the library is the "fusion" of compile time metaprogramming with runtime programming. Review questions ================ Please always explicitly state in your review, whether you think the library should be accepted into Boost. You might want to comment on the following questions: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With what compiler? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? Cheers, Ron

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Re: [Boost-users] [multi_index] thread safety
by Patel Priyank-PPATEL1 13 May '06

13 May '06

Hi Joaquin, I have to use actually two or more threads on procedure pool. I start seeing same Problem when I have three/four threads working on same procedure pool. I tried to introduce mutex (ACE_Guard) but still having problems in execution in one/two minute of execution. Seems I am guarding every method that is used by container. Anything wrong with the Following code? Thanks Priyank #ifndef PROCEDURE_POOL_H #define PROCEDURE_POOL_H /** * Identifier pool of procedure. This procedure will be un-sorted * hashed index provided by procedures unique id retuned by procedure. * It internally uses boost hashed index for indexing the procedures * in procedure pool. * * @author Priyank Patel * @since Mar 30, 2006 */ #include <ace/Mutex.h> #include <boost/multi_index_container.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/config.hpp> #include <boost/utility.hpp> #include <boost/shared_ptr.hpp> #include <boost/multi_index/key_extractors.hpp> #include "Procedure.h" using boost::multi_index_container; using namespace boost::multi_index; /** * Defines tag used for procedure id. */ struct procedure_id_tag { }; class Procedure_Pool: boost::noncopyable { private: /** * Type definition for multi index container. */ typedef multi_index_container< Procedure*, indexed_by< hashed_unique< tag<procedure_id_tag>, const_mem_fun<Procedure, int, &Procedure::id> > > > Procedure_Hashed_Pool; /** * Type definition for indexing based on procedure id tag. */ typedef Procedure_Hashed_Pool::index<procedure_id_tag>::type Procedure_By_Id; public: /** * Constructor. */ Procedure_Pool(): pool_(), procedure_by_id_(pool_.get<procedure_id_tag>()) { } /** * Adds specified procedure in this pool. * It will intenally used procedures id() method to index procedure. * @param _procedure Procedure to be added in this pool * @return Success (0) or Failure (-1) based on addition happened or not */ int add_by_id(Procedure * _procedure); /** * Removes procedure from this pool. * @param _procedure procedure that needs to be removed * @return Success (0) or Failure (1) based on removal happend or not */ int remove_by_id(Procedure * _procedure); /** * Retrieves procedure based on specified id. * @param _id Identifier * @return Procedure Pointer to procedure. Returns 0 if procedure not found */ Procedure * find_by_id(int _id); private: /** * Returns true if procedure is present otherwise returns false. * @param _procedure procedure that needs to found * @return true if found or false if not found */ //bool find_by_id(Procedure * _procedure); /** * boost multiindex object that is associated with this pool. */ Procedure_Hashed_Pool pool_; /** * Refernece of pool that is indexed by procedure id tag. */ Procedure_By_Id &procedure_by_id_; ACE_Mutex mutex_; }; #endif //===============================================================================/// #include "../include/Procedure_Pool.h" int Procedure_Pool::add_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::add_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "ADDING %d\n", _procedure->id())); if (find_by_id(_procedure->id()) == 0) { ACE_Guard<ACE_Mutex> guard(mutex_); { // procedure not found procedure_by_id_.insert(_procedure); } // debug info ACE_DEBUG((LM_DEBUG, "Added procedure : %d \n", _procedure->id())); // return success return 0; } else { // error ACE_ERROR((LD_ERROR "%N:%l Error in adding procedure : %d \n", _procedure->id())); // return failure return -1; } } int Procedure_Pool::remove_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::remove_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "REMOVING: %d \n", _procedure->id())); if (find_by_id(_procedure->id()) != 0) { ACE_Guard<ACE_Mutex> guard(mutex_); { // procedure found procedure_by_id_.erase(_procedure->id()); } ACE_DEBUG((LM_DEBUG, "Removed procedure : %d \n", _procedure->id())); return 0; } else { ACE_ERROR((LD_ERROR "%N:%l Error in removing procedure : %d \n", _procedure->id())); return -1; } } Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_Guard<ACE_Mutex> guard(mutex_); { Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); return *it; } } ACE_DEBUG((LM_DEBUG, "%N:%l Not able to found procedure for id: %d \n", _id)); // return null return 0; } -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Thursday, May 11, 2006 2:12 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] thread safety ----- Mensaje original ----- De: george <george13p(a)yahoo.com> Fecha: Jueves, Mayo 11, 2006 7:27 pm Asunto: Re: [Boost-users] [multi_index] thread safety > hello Joaquin Hello George, > > > You have to lockguard every access to the container; note this also > > includes, for instance, container traversal with iterators, i.e. > > iterator displacement. Strictly speaking, iterator dereference > > should also be lockguarded, although I can say unofficially that > > unguarded dereference is OK. > > can you explain a litle more? > as I konw from STL, multiple readers is ok. Correct. > reading and inserting a new object does't invalidate iterators(for > pointer-based conteiners offcourse,list, map etc...) Correct. This also holds for multi_index_containers. > > a concurrent read and insert in multi_index are not (safely)possible? > I mean there might be an iterator invalidation? Concurrent reading and writing is not safe, but the issue has nothing to do with iterator invalidation. ...I think I've got a hunch about what you've got in mind. When I say that you've got to lockguard iterator displacement, what I mean is: consider a concurrent write operation and an iterator increment; this concurrency is not thread safe and undefined behavior results: a possible outcome is iterator invalidation, but you could also get an app crash, a corrupted data structure, an infinite loop or whatever. Tecnhically speaking, an invalid iterator is a perfectly legal state for an iterator to be in, which has nothing to do with undefined behavior resulting from violating thread safety guarantees. I'm not sure I made myself clear :) Insist on me if I didn't. > offcourse there is a chance for a 'dirty-read' but this for the domain > of the aplication if it is a problem and not for multi_index. I don't get what you mean here, would you care to elaborate? Joaquín M López Muñoz Telefónica, Investigación y Desarrollo _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

2 1

boost::bind, boost::function & placeholders flexibility
by jbd 13 May '06

13 May '06

Hello everybody, First of all, i'm a beginner trying to understand the use of the boost::bind library. Here is my problem : I'd like to know if there is a way to omit placeholders when calling boost::bind and let the compiler deduce their number. I understand that this is contrary to the flexibility offers by the placeholder, but i need to do something like that. void bar() {} void bar2(int) {} // Compile and works well boost::function < void ()> f1( boost::bind(&bar) ) ; boost::function < void (int) > f2( boost::bind(&bar2,_1) ) ; // i'd like to write this, but it doesn't compile // without the placeholders boost::function < void (int) > f2( boost::bind(&bar2) ) ; // i can write a small helper function mybind to achieve my goal // this compile and works well mybind(bar2) ; with template <typename Ret, typename Arg1, typename Arg2> void mybind(Ret (*Func)(Arg1, Arg2)) { boost::function<Ret (Arg1, Arg2)> f(Func) ; } I hope you understand what i've try to show. Maybe i missed something in the documentation. Thank you for reading ! Here is the working .cpp file i use to test things. =============================== #include <iostream> #include <stdexcept> #include <boost/bind.hpp> #include <boost/function.hpp> template <typename Ret, typename Arg1, typename Arg2> void mybind(Ret (*Func)(Arg1)) { boost::function<Ret (Arg1)> f(Func) ; } void bar() { std::cout << "bar()\n" ; } void bar2(int a) { std::cout << "bar2(int)\n" ; } int main (int argc, char* argv[]) { try { // Compile and works well { boost::function < void ()> f1( boost::bind(&bar) ) ; boost::function < void (int) > f2( boost::bind(&bar2,_1) ) ; } /* // i'd like to write this, but it doesn't compile { // without the placeholders boost::function < void (int) > f2( boost::bind(&bar2) ) ; f2(5) ; } */ // i can write a small helper function mybind to achieve my goal // this compile and works well /* template <typename Ret, typename Arg1, typename Arg2> void mybind(Ret (*Func)(Arg1, Arg2)) { boost::function<Ret (Arg1, Arg2)> f(Func) ; } */ { mybind(bar2) ; } } catch(std::exception& e) { std::cout << e.what() << '\n' ; return -1 ; } catch(...) { std::cout << "Non standard exception\n" ; return -1 ; } } ========================================

5 8

Linking problems with boost::test in multiple modules.
by steve ahlgren 12 May '06

12 May '06

Hello : I am using boost::test to provide testing in multiple modules (dlls on win32). A single exe is used to call each of the test facilities in each module. In theory the above sounds ideal, especially as each individual unit test within a module is registered via an abstract factory. In practice, however, I am unable to link the individual modules properly as each one seems to require the function init_unit_test_suite() to be defined. This is mentioned in the FAQ but I have not yet found documentation or examples documenting boost::test spanning multiple modules. I would think that one instance of init_unit_test_suite() would be necessary within the controlling exe, and that each module (dll) would link statically against the boost::test library. Linking against this library, however, causes the problems described above. If anyone has suggestions or an example I would be grateful. Many thanks; sga

3 4

Re: [Boost-users] [BULK] Re: MPL/Fusion
by Sohail Somani 12 May '06

12 May '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Arkadiy Vertleyb > There could be different opinions on this subject, but I > think the basic > rule of thumb should be: no template metaprogramming in the > non-library > code. Of course, most C++ programmers are wearing two hats: a library > (reusable code) writer and the user of this reusable code. > The key is to > distinguish which hat you are wearing at any particular moment :-) I find that increasingly it's the library, so maybe I'm on the right path. Thank you for your input! Sohail

1 0

Re: [Boost-users] MPL/Fusion
by Sohail Somani 12 May '06

12 May '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Sohail Somani > Sent: Thursday, May 11, 2006 9:18 AM > To: boost-users(a)lists.boost.org > Subject: [Boost-users] MPL/Fusion > > Hi, > > I am quite interested in MPL/Fusion. I have made my own toy projects > using template metaprogramming to make decisions at compile time. I am > interested in learning what types of software boost users create with > it. > > Would anyone care to share? I think I should clarify: I meant non-library uses (like the maze app, I'll take a look thanks!). Like a programmer who also uses shared_ptr. Although I can think of a few instances where I would use it for work, I just want to tell myself that I am making things complicated and want your help to make sure I'm making better code. Sorry if that's even MORE confusing :) Sohail

2 1

[date_time] Error in time_period documentation
by Ward, Arthur (Mission Systems) 12 May '06

12 May '06

To the documentation maintainers for date_time: I just noticed an error in the documentation for boost::posix_time::time_period in 1.33.1. According to the Posix Time documentation, time_period has the method "time_period shift(days)". As far as I can see, it should be "void shift(days)" and listed as a mutator.

2 1

[Boost.program_options] Boolean option
by Kobi Cohen-Arazi 12 May '06

12 May '06

Hi, boost-1.32.0-6 I've tried to find in the program_options docs how to specify a regular boolean switch. If I use <bool>, it still demand putting something That's what I would like to have ./prog -t and not ./prog -t1 Right now, when using <bool> it will throw an exception if I'm not using the -t1 notation. Am I missing here something? Thanks, Kobi.

2 2

[Boost.dynamic_bitset] Help on extending dynamic_bitset
by Kobi Cohen-Arazi 12 May '06

12 May '06

Hi, boost-1.32.0-6 I would like to hear your suggestions regarding the ways to extend dynamic_bitset. Let's say that I have a different way to search for the next bit in the set. It is specific to my CPU arch. How can I extend find_first/find_next ? Since there is no way to retrieve the internal vector<>, It seems very hard to do so. Nothing is protected so Inheritance is out of the question, and there is not a single accessor that expose that vector<> (its best not to do so, but I'm just counting the options here). Am I missing another way of extending it? Thanks, Kobi.

1 0

[date_time] build error
by Leif Gruenwoldt 12 May '06

12 May '06

I have implemented a class ( lets call it LC2DateTime ) that uses boost date time in it's implementation. I also have a small test for this class and it builds nicely and runs properly. However when I include LC2DateTime.h in my larger project I get this odd build error that points me to /usr/include/boost/algorithm/string/detail/finder.hpp as the source of the error. ------------------ /usr/include/boost/algorithm/string/detail/finder.hpp: In member function 'boost::iterator_range<Iterator> boost::algorithm::detail::last_finderF<SearchIteratorT, PredicateT>::findit(ForwardIteratorT, ForwardIteratorT, std::forward_iterator_tag) const': /usr/include/boost/algorithm/string/detail/finder.hpp:150: error: expected unqualified-id before numeric constant /usr/include/boost/algorithm/string/detail/util.hpp: At global scope: /usr/include/boost/algorithm/string/detail/util.hpp:71: error: expected ',' or '...' before numeric constant /usr/include/boost/algorithm/string/detail/util.hpp: In function 'OutputIteratorT boost::algorithm::detail::bounded_copy(InputIteratorT, InputIteratorT)': /usr/include/boost/algorithm/string/detail/util.hpp:76: error: 'DestFirst' was not declared in this scope /usr/include/boost/algorithm/string/detail/util.hpp:77: error: 'DestLast' was not declared in this scope ---------------------- This bug has been bothering me for a while and I actually got my project to build again juggling the placement of of the '#include "LC2DateTime.h" above the other includes in my project. However this problem has reared it's head again and this time no amount of juggling of includes is getting me out of this. Any thoughts? Is this a problem with the boost libraries or my code? -- Leif Gruenwoldt Simulation Software Developer DLCSPM 4-4-3 (c) Building A31 CFB Kingston

2 6

Mailing lists to go down Saturday
by David Abrahams 12 May '06

12 May '06

-- Dave Abrahams Boost Consulting www.boost-consulting.com

1 0

a problem on boost::asio
by 李慧霸 12 May '06

12 May '06

I'm trying asio on WindowsXPSP2 + VS2003, and I found that there are always some connections established from 127.0.0.1:xxxx to 127.0.0.1:yyyy, is it a bug?

2 1

Re: [Boost-users] [Wave] effect of allocation of data structures oncopying data structures
by Hartmut Kaiser 12 May '06

12 May '06

> Andreas Sæbjørnsen wrote: > > > I need some advice regarding how I should copy the boost data > > structures I get from 'advanced_preprocessing_hooks.h'. > > The task at hand is to copy some of the data structures > from Wave and > > store it separate form the memory Wave allocates so that after the > > Wave preprocessing step has finished all it's memory can be freed. > > > > Example: e.g making a copy of the > > 'std::vector<std::list<PreprocessingInfo::token_type,boost::fa > > st_pool_allocator<PreprocessingInfo::token_type> > >' > > representing the arguments in the expansion of a macro in > the function > > 'expanding_function_like_macro'. > > > > Syntactically it would be gre at to be able to make a copy > using the > > operator=, but as far as I can see this is only possible if > I am also > > using the fast_pool_allocator. If I use the > fast_pool_allocator I am > > afraid that my copies will be put into the memory pool allocated by > > Wave and therefore that memory cannot be safely freed. Is > this corect? > > I'm not sure here. My (unverified) guess is, that the memory > pool will be free'd only after the last item allocated from > it got free'd. This shouldn't be a problem as long as the > memory pool doesn't live in a shared library which gets > unloaded prematurely. After looking at the code and the docs again I discovered the following: the boost::fast_pool_allocator is build on top of a thread local singleton pool. This pool gets allocated before entering main and gets free'd after main exits. Same should be true for shared libraries. So yes, you're running into problems only: 1) if you have your Wave application compiled into a shared library and 2) if you use data from the allocator used by Wave in a different module after the first shared library was explicitely unloaded from memory. HTH Regards Hartmut > But anyway, doesn't using std::copy() for the embedded > list<>'s allow to change to any adequate data structure? > > Regards Hartmut >

2 3

Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 11 May '06

11 May '06

Hi Kobi, I am using ACE_Mutex. Let me check ACE Guards (I know there is ACE_Guard class), Is that what you mean? Thanks Priyank ________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Kobi Cohen-Arazi Sent: Thursday, May 11, 2006 11:09 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); mutex_.acquire(); Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); mutex_.release(); return *it; } ACE_DEBUG((LM_DEBUG, "%N:%l Not able to found procedure for id: %d \n", _id)); mutex_.release(); // return null return 0; } BTW, As a side note, I highly recommend you to use ACE Guards (RAII...) for the mutex thing. Kobi

2 1

MPL/Fusion
by Sohail Somani 11 May '06

11 May '06

Hi, I am quite interested in MPL/Fusion. I have made my own toy projects using template metaprogramming to make decisions at compile time. I am interested in learning what types of software boost users create with it. Would anyone care to share? Thanks! Sohail

3 2

Re: [Boost-users] [multi_index] thread safety
by JOAQUIN LOPEZ MU?Z 11 May '06

11 May '06

----- Mensaje original ----- De: george <george13p(a)yahoo.com> Fecha: Jueves, Mayo 11, 2006 7:27 pm Asunto: Re: [Boost-users] [multi_index] thread safety > hello Joaquin Hello George, > > > You have to lockguard every access to the container; note this > > also includes, for instance, container traversal with iterators, > > i.e. iterator displacement. Strictly speaking, iterator dereference > > should also be lockguarded, although I can say unofficially that > > unguarded dereference is OK. > > can you explain a litle more? > as I konw from STL, multiple readers is ok. Correct. > reading and inserting a new object does't invalidate iterators(for > pointer-based > conteiners offcourse,list, map etc...) Correct. This also holds for multi_index_containers. > > a concurrent read and insert in multi_index are not > (safely)possible? I mean there might be an iterator > invalidation? Concurrent reading and writing is not safe, but the issue has nothing to do with iterator invalidation. ...I think I've got a hunch about what you've got in mind. When I say that you've got to lockguard iterator displacement, what I mean is: consider a concurrent write operation and an iterator increment; this concurrency is not thread safe and undefined behavior results: a possible outcome is iterator invalidation, but you could also get an app crash, a corrupted data structure, an infinite loop or whatever. Tecnhically speaking, an invalid iterator is a perfectly legal state for an iterator to be in, which has nothing to do with undefined behavior resulting from violating thread safety guarantees. I'm not sure I made myself clear :) Insist on me if I didn't. > offcourse there is a chance for a 'dirty-read' but this for the > domain of the aplication if it is a problem and not for multi_index. I don't get what you mean here, would you care to elaborate? Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

1 0

Re: [Boost-users] [multi_index] thread safety
by Joaquín Mª López Muñoz 11 May '06

11 May '06

Conway Allen ha escrito: > Regarding thread safety, if threads are concurrently reading, > inserting, and erasing entries in a multi-index container do you have to > lockguard all of these operations or can you get away with just > lockguarding the inserts and the deletes? You have to lockguard every access to the container; note this also includes, for instance, container traversal with iterators, i.e. iterator displacement. Strictly speaking, iterator dereference should also be lockguarded, although I can say unofficially that unguarded dereference is OK. The kind of thread-safety provided by B.MI (and by most STL implementations) is described at SGI docs: http://www.sgi.com/tech/stl/thread_safety.html > Thanks, Allen. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

2 1

Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 11 May '06

11 May '06

Hi Joaquin, I have put some locks in code and follows is the changed code. Also, I have removed API that takes procedure pointer. Instead it just takes id as input. Anyways, It seems to be working GREAT. Thanks for all your help. Will contact you incase of any problems. #include "../include/Procedure_Pool.h" int Procedure_Pool::add_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::add_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "ADDING %d\n", _procedure->id())); if (find_by_id(_procedure->id()) == 0) { // procedure not found mutex_.acquire(); procedure_by_id_.insert(_procedure); mutex_.release(); // debug info ACE_DEBUG((LM_DEBUG, "Added procedure : %d \n", _procedure->id())); // return success return 0; } else { // error ACE_ERROR((LD_ERROR "%N:%l Error in adding procedure : %d \n", _procedure->id())); // return failure return -1; } } int Procedure_Pool::remove_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::remove_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "REMOVING: %d \n", _procedure->id())); if (find_by_id(_procedure->id()) != 0) { // procedure found mutex_.acquire(); procedure_by_id_.erase(_procedure->id()); mutex_.release(); ACE_DEBUG((LM_DEBUG, "Removed procedure : %d \n", _procedure->id())); return 0; } else { ACE_ERROR((LD_ERROR "%N:%l Error in removing procedure : %d \n", _procedure->id())); return -1; } } Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); mutex_.acquire(); Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); mutex_.release(); return *it; } ACE_DEBUG((LM_DEBUG, "%N:%l Not able to found procedure for id: %d \n", _id)); mutex_.release(); // return null return 0; } Thanks, Priyank -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Wednesday, May 10, 2006 4:36 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! ----- Mensaje original ----- De: Patel Priyank-PPATEL1 <priyankpatel(a)motorola.com> Fecha: Miércoles, Mayo 10, 2006 10:49 pm Asunto: Re: [Boost-users] [multi_index] Core dump in multi-index library !! > Hi Joaquin, [...] > One other thing, addition and deletionIs done by separate threads in > my application. Oh, oh. multi_index_container is *not* thread safe, so this smells like the problem --and it is not, it certainly has the potential to crash your app sooner or later. Please take into account thread unsafety extends to every member function of multi_index_container, so you'd better lockguard *every* public method of Procedure_Pool. Looking fwd to knowing your results. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo In case you're wondering, STL implementations typically have the same level of thread safety as B.MI provides: 1. Concurrent access to different containers is safe. 2. Concurrent read-only access to the same container is safe. The rationale is that locking every public method of an STL container adds an unavoidable runtime overhead (you might not need it), and moreover it doesn't necessarily map to what constitutes *atomicity* to a given app --in your case, for instance, atomicity, and thus lockguarding, is best done at the level of Procedue_Pool interface. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[BGL]: Highest performance graph-type available?
by Greg Link 11 May '06

11 May '06

I'm using BGL for the johnson_all_pairs_shortest_path algorithm, and spending about 98% of my runtime in that algorithm. Breaking it down, the BFS_visit itself is consuming some 85% of my total runtime. Hence, any and every improvement I can get in my BGL performance will make my app much much snappier. Currently, my graph type is a adjacency_list <vecS, vecS, undirectedS, no_property, property <edge_weight_t, double> > and I'm wondering if that's the best choice. My graph has (E=2*V), and all nodes are of constant degree, with 4 edges incident on them. V is usually in the range of 150-500. Would one of the other types (such as listS) perhaps be faster, and still work? I know some BGL algorithms require certain graph storage types, so I'm hesitant to just start poking around and trying random things. That, and other than "listS", I don't know of any other types of graph, as I'm quite new to both the BGL and boost in general. Any thoughts on what might make things faster? Additionally, are there any compiler flags I should consider other than the 'vanilla' ones? (-O3). I'm using GCC 4.0.1 currently, if it matters. Thanks for the great library, and such a friendly list, Greg Link

4 5

Problem with lambda expressions and uint64_t
by Olatunde Adonai 11 May '06

11 May '06

The following code compiles with f as a uint32_t. It does not compile with f as a uint64_t. Why is this? What can be done? #include <iostream> #include <algorithm> #include <boost/lambda/lambda.hpp> using std::cout; using std::for_each; using namespace boost::lambda; int main(int argc, const char* argv[]) { const char s[] = "abcdefghi"; //Problem: uint64_t f = 0xaa; //This compiles as a uint32_t. unsigned int i = 0; for_each(s , &s[sizeof(s) - 1] , cout << _1 << " = " << var(i)++ << " (" << ( ( f >> var(i) ) & 1 ) << ")\n" ); return 0; } __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

1 0

boost::iostreams regex_filter crash
by Andrew McDonald 11 May '06

11 May '06

I am using boost_1_33_1, in Microsoft Visual C++ 2005 Express Edition version 8.0.50727.42. Boost has been built with the vc-8_0 toolset. When using a filtering_stream with a regex_filter I get a crash in cases where the filtering_stream is destroyed (i.e. closed) having processed text without any match for the regex. =========================================================== #include <boost/iostreams/filtering_stream.hpp> #include <boost/iostreams/filter/regex.hpp> #include <iostream> using namespace boost; using namespace boost::iostreams; // replaces y with Q const regex_filter Y_FILTER ( regex("y") ,"Q" ); // replaces x with Q const regex_filter X_FILTER ( regex("x") ,"Q" ); // test data has a y but no x const char* Y_BUT_NO_X = "abc y cba"; void test() { // outputs "abc Q cba" as expected { filtering_ostream out( Y_FILTER ); out.push(std::cout); out << Y_BUT_NO_X; } // crashes with null pointer dereference !!! { filtering_ostream out( X_FILTER ); out.push(std::cout); out << Y_BUT_NO_X; } } =========================================================== Please note that the same crash occurs with "real world" regex's and data so the issue is not caused by boundary conditions due to the "artificial" test data. It is generically caused by the condition of not matching the regex. The crash occurs at line 53 of boost/iostreams/filter/regex.hpp in the function void do_filter(const vector_type& src, vector_type& dest) { typedef regex_iterator<const Ch*, Ch, Tr> iterator; if (src.empty()) return; iterator first(&src[0], &src[0] + src.size(), re_, flags_); iterator last; const Ch* suffix = 0; // Prevent GCC 2.95 warning. for (; first != last; ++first) { dest.insert( dest.end(), first->prefix().first, first->prefix().second ); string_type replacement = replace_(*first); dest.insert( dest.end(), replacement.begin(), replacement.end() ); suffix = first->suffix().first; } dest.insert(dest.end(), suffix, &src[0] + src.size()); <<< Crash !! } In cases where no regex match will occur then first == last, the for loop body is never run and consequently suffix remains initialised to 0. Consequently its use in the line succeeding the loop body causes a crash. The intent of this last line is to copy any text remaining after the last match from the src to the dest. This means that an appropriate initialiser for suffix is the start of the src, so that all text is copied to the destination if no match occurs. This can be achieved by altering the line; const Ch* suffix = 0; // Prevent GCC 2.95 warning. to const Ch* suffix = &src[0]; // Prevent GCC 2.95 warning. However a small rewrite avoids several calls to operator[] and size() and makes the code (ever so slightly) more readable; void do_filter(const vector_type& src, vector_type& dest) { typedef regex_iterator<const Ch*, Ch, Tr> iterator; if (src.empty()) return; const Ch* start = &src[0]; const Ch* end = start + src.size(); const Ch* suffix = start; // Prevent GCC 2.95 warning. iterator first(start, end, re_, flags_); iterator last; for (; first != last; ++first) { dest.insert( dest.end(), first->prefix().first, first->prefix().second ); string_type replacement = replace_(*first); dest.insert( dest.end(), replacement.begin(), replacement.end() ); suffix = first->suffix().first; } dest.insert(dest.end(), suffix, end); } I have tested this with both the test() function above and my original data and correct output is produced. regards, Andrew Andrew McDonald System Architect > Norwood Systems Australia Pty Ltd Level 1, 71 Troy Terrace PO Box 1281 Subiaco, WA 6904 > Tel +61 8 9380 7766 > Fax +61 8 9380 7733 andrew.mcdonald(a)norwoodsystems.com > > The information in this email, and any attachments, may contain confidential information and is intended solely for the attention and use of the named addressee (s). It must not be disclosed to any person(s) without authorization. If you are not the intended recipient, or a person responsible for delivering it to the intended recipient, you are not authorized to, and must not, disclose, copy, distribute, or retain this message or any part of it. If you have received this communication in error, please notify the sender immediately. > > > > > > > > > > > > >

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Re: [Boost-users] Compiling boost on Sol 5.2 compiler
by paul.floyd 11 May '06

11 May '06

> Hi, > > I am trying to use boost with Solaris 5.2 compiler. I am getting a compiler > error as a result of the macor BOOST_AUX_NTTP_DECL not being defined > anywhere. I would appreciate it very much if anyone could point me how I can > get past this stage. You won't get very far with Forte 6 update 1 (it is old, and no longer supported). I would suggest that you get either Studio 10 (available for free via opensolaris.org) or Studio 11 (available for free from Sun). At least, if you can't switch to either of those versions of Sun Studio, I'd consider trying to get Forte 6 update 2. This is a bit less old, and was supported up till about 6 months ago, and it should work OK with the same licence as Forte 6u1. However, it's still too old to compile fairly major chunks of Boost. Next take a look at http://blogs.sun.com/roller/page/sga This should get you much closer to being able to use most of Boost. A+ Paul Accédez au courrier électronique de La Poste : www.laposte.net ; 3615 LAPOSTENET (0,34 /mn) ; tél : 08 92 68 13 50 (0,34/mn)

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boost::iostreams pipelines with ostream causes compilation error
by Andrew McDonald 11 May '06

11 May '06

Hi, I have just recently started using the boost::iostreams library, so apologies if my question is obvious. I have tried checking doco and mailing list to see if this issue is already covered. I am using boost_1_33_1, in Microsoft Visual C++ 2005 Express Edition version 8.0.50727.42. Boost has been built with the vc-8_0 toolset. When attempting to use pipelines with filtering_streams I get an error when attempting to add an ostream as the (terminating) device for the pipeline The following (inline) test program illustrates various combinations that compile with the problem usage as the last example =============================================================== #include <boost/iostreams/filtering_stream.hpp> #include <boost/iostreams/filter/regex.hpp> #include <boost/iostreams/device/file.hpp> #include <iostream> using namespace boost::iostreams; void test(std::ostream& os, regex_filter& f) { // pipeline with no device - ok { filtering_ostream out( f | f ); out.push(os); } // explicitly pushing file sink - ok { filtering_ostream out( f | f ); out.push(file_sink("test.txt")); } // explicitly pushing ostream - ok { filtering_ostream out( f | f ); out.push(os); } // only a file sink - ok { filtering_ostream out(file_sink("test.txt")); } // only an ostream - ok { filtering_ostream out(os); } // pipeline with file sink - ok { filtering_ostream out( f | f | file_sink("test.txt") ); } // pipline with ostream - not ok !! { // compilation error filtering_ostream out( f | f | os ); } } =============================================================== The error generated is: boost/iostreams/pipeline.hpp(107) : error C2664: 'void boost::iostreams::detail::chain_client<Chain>::push<char,std::char_traits<char>>(std::basic_ostream<_Elem,_Traits> &,int,int)' : cannot convert parameter 1 from 'const std::ostream' to 'std::basic_ostream<_Elem,_Traits> &' with [ Chain=boost::iostreams::chain<boost::iostreams::output,char,std::char_traits<char>,std::allocator<char>>, _Elem=char, _Traits=std::char_traits<char> ] and [ _Elem=char, _Traits=std::char_traits<char> ] Conversion loses qualifiers This appears to be caused by the fact that the implementation of the push() method on struct pipeline calls chn.push(component_); where the component_ member is held by const ref. The push() method on Chain is generated with BOOST_IOSTREAMS_DEFINE_PUSH(push, mode, char_type, push_impl) which is commented with a cut-and-paste of the comment for the preceding macro, as // // Macro: BOOST_IOSTREAMS_DEFINE_PUSH_CONSTRUCTOR(mode, name, helper). // Description: Defines constructors which forward to a function // 'helper' which takes a filter or device by const reference. However via BOOST_IOSTREAMS_DEFINE_PUSH_IMPL this appears to generate a method requiring a non-const reference; ::std::basic_streambuf<CharType, TraitsType>& sb Am I missing something here ? I was wondering whether this was intentional and whether the syntactic form filtering_ostream out( f | f | os ) was meant to be supported. Andrew McDonald System Architect > Norwood Systems Australia Pty Ltd Level 1, 71 Troy Terrace PO Box 1281 Subiaco, WA 6904 > Tel +61 8 9380 7766 > Fax +61 8 9380 7733 andrew.mcdonald(a)norwoodsystems.com > > The information in this email, and any attachments, may contain confidential information and is intended solely for the attention and use of the named addressee (s). It must not be disclosed to any person(s) without authorization. If you are not the intended recipient, or a person responsible for delivering it to the intended recipient, you are not authorized to, and must not, disclose, copy, distribute, or retain this message or any part of> it. If you have received this communication in error, please notify the sender immediately. > > > >

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Re: [Boost-users] [multi_index] thread safety
by Conway Allen 11 May '06

11 May '06

Regarding thread safety, if threads are concurrently reading, inserting, and erasing entries in a multi-index container do you have to lockguard all of these operations or can you get away with just lockguarding the inserts and the deletes? Thanks, Allen. -----Message d'origine----- De : boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] De la part de JOAQUIN LOPEZ MU?Z Envoyé : mercredi 10 mai 2006 23:36 À : boost-users(a)lists.boost.org Objet : Re: [Boost-users] [multi_index] Core dump in multi-index library !! Oh, oh. multi_index_container is *not* thread safe, so this smells like the problem --and it is not, it certainly has the potential to crash your app sooner or later. Please take into account thread unsafety extends to every member function of multi_index_container, so you'd better lockguard *every* public method of Procedure_Pool. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Re: [Boost-users] Template instantiation problem
by Gottlob Frege 11 May '06

11 May '06

Date: Wed, 10 May 2006 15:30:08 -0700 > From: Rush Manbert <rush(a)manbert.com> > Subject: [Boost-users] Template instantiation problem > To: boost-users(a)lists.boost.org > Message-ID: <44626970.4070704(a)manbert.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > I have a template class that is designed to contain built in types or > std::string types. I always need to be able to cast an instance of the > class as a std::string, and I also need to be able to cast it as the > parameter type with which it was instantiated. > > In my class definition, I have defined two cast operators, like so: > (Extraneous stuff omitted) > > template<typename T> > class MyDataObject : public MyDataObjectBase > { > > // Cast as std::string > inline operator const std::string & () > { > ...some code here > } > > // Cast as T > inline operator const T & () > { > ...some code here > } > } > > The original code was written on a Mac and compiled with Gnu, which did > not complain. even when I did this: > > class MyStringObjectClass : public MyDataObject<std::string> > { > } > > Now, however, I have moved the code to Windows, and the Visual Studio > compiler complains about the second cast operator when I define > MyStringObjectClass. > > I thought that if I could conditionally define the cast as T operator > (or the cast as std::string) I would be okay, but that means testing > against the value of T with the preprocessor. I don't see how to do > that, but I know that some of you folks are really good at bending the > preprocessor to your will. > > Can anyone show me a way out of this predicament? > > Thanks, > Rush Take a look at enable_if. ie boost::mpl::enable_if I think. Also is_same. With those you can check if your T is_same as std::string, and enable (or disable) your operators accordingly. Tony.

1 0

Template instantiation problem
by Rush Manbert 11 May '06

11 May '06

I have a template class that is designed to contain built in types or std::string types. I always need to be able to cast an instance of the class as a std::string, and I also need to be able to cast it as the parameter type with which it was instantiated. In my class definition, I have defined two cast operators, like so: (Extraneous stuff omitted) template<typename T> class MyDataObject : public MyDataObjectBase { // Cast as std::string inline operator const std::string & () { ...some code here } // Cast as T inline operator const T & () { ...some code here } } The original code was written on a Mac and compiled with Gnu, which did not complain. even when I did this: class MyStringObjectClass : public MyDataObject<std::string> { } Now, however, I have moved the code to Windows, and the Visual Studio compiler complains about the second cast operator when I define MyStringObjectClass. I thought that if I could conditionally define the cast as T operator (or the cast as std::string) I would be okay, but that means testing against the value of T with the preprocessor. I don't see how to do that, but I know that some of you folks are really good at bending the preprocessor to your will. Can anyone show me a way out of this predicament? Thanks, Rush

3 2

Compiling boost on Sol 5.2 compiler
by Vadivelu Rahuraman 11 May '06

11 May '06

Hi, I am trying to use boost with Solaris 5.2 compiler. I am getting a compiler error as a result of the macor BOOST_AUX_NTTP_DECL not being defined anywhere. I would appreciate it very much if anyone could point me how I can get past this stage. Thanks, Rahu

1 0

[Wave] effect of allocation of data structures on copying data structures
by Andreas Sæbjørnsen 10 May '06

10 May '06

I need some advice regarding how I should copy the boost data structures I get from 'advanced_preprocessing_hooks.h'. The task at hand is to copy some of the data structures from Wave and store it separate form the memory Wave allocates so that after the Wave preprocessing step has finished all it's memory can be freed. Example: e.g making a copy of the 'std::vector<std::list<PreprocessingInfo::token_type,boost::fast_pool_allocator<PreprocessingInfo::token_type> > >' representing the arguments in the expansion of a macro in the function 'expanding_function_like_macro'. Syntactically it would be gre at to be able to make a copy using the operator=, but as far as I can see this is only possible if I am also using the fast_pool_allocator. If I use the fast_pool_allocator I am afraid that my copies will be put into the memory pool allocated by Wave and therefore that memory cannot be safely freed. Is this corect? .

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by JOAQUIN LOPEZ MU?Z 10 May '06

10 May '06

----- Mensaje original ----- De: Patel Priyank-PPATEL1 <priyankpatel(a)motorola.com> Fecha: Miércoles, Mayo 10, 2006 10:49 pm Asunto: Re: [Boost-users] [multi_index] Core dump in multi-index library !! > Hi Joaquin, [...] > One other thing, addition and deletionIs done by separate > threads in my application. Oh, oh. multi_index_container is *not* thread safe, so this smells like the problem --and it is not, it certainly has the potential to crash your app sooner or later. Please take into account thread unsafety extends to every member function of multi_index_container, so you'd better lockguard *every* public method of Procedure_Pool. Looking fwd to knowing your results. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo In case you're wondering, STL implementations typically have the same level of thread safety as B.MI provides: 1. Concurrent access to different containers is safe. 2. Concurrent read-only access to the same container is safe. The rationale is that locking every public method of an STL container adds an unavoidable runtime overhead (you might not need it), and moreover it doesn't necessarily map to what constitutes *atomicity* to a given app --in your case, for instance, atomicity, and thus lockguarding, is best done at the level of Procedue_Pool interface.

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Hi Joaquin, As I said, I think the problem is during addition and not delete. I have tried to build my application with debug mode and have some more printouts for you. Please let me know if this helps or not. Everything goes smooth for a while but suddenly it stops working. I even Removed delete calls but the problem still exists. One other thing, addition and deletion Is done by separate threads in my application. I am trying now to lock/unlock pool when I do addition/deletion and see whether that works or not. Let me know if you need any More information relating this. Thanks a lot for your help. Thread id (8) adds procedures in procedure pool while thread id (4) removes Procedure from procedure pool. // SOME TRACE WHILE EXECUTING LD_TRACE: (8) In Method: Procedure_Executor::handle_timeout File: `src/apps/executor/Procedure_Executor.cpp' Line: 67 LD_TRACE: (8) In Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) Out Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) In Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) Out Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) In Method: Sample_Procedure::Sample_Procedure File: `src/apps/procedure/Sample_Procedure.cpp' Line: 9 LD_TRACE: (8) Out Method: Sample_Procedure::Sample_Procedure File: `src/apps/procedure/Sample_Procedure.cpp' Line: 9 LD_TRACE: (8) In Method: Access_Point::subscribe File: `src/apps/network_element/Access_Point.cpp' Line: 181 LD_TRACE: (8) In Method: AP_TCP_Connection::subscribe File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 81 LD_TRACE: (8) In Method: Procedure_Pool::add_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 5 FIND CALL FROM ADD LD_TRACE: (8) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 src/core/procedure/Procedure_Pool.cpp:47 Not able to found procedure for id: 1646 LD_TRACE: (8) Out Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 Added procedure : 1646 LD_TRACE: (8) Out Method: Procedure_Pool::add_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 5 src/apps/connector/AP_TCP_Connection.cpp:88 Subscribed sample type procedure LD_TRACE: (8) Out Method: AP_TCP_Connection::subscribe File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 81 LD_TRACE: (8) Out Method: Access_Point::subscribe File: `src/apps/network_element/Access_Point.cpp' Line: 181 LD_TRACE: (8) In Method: Sample_Procedure::start File: `src/apps/procedure/Sample_Procedure.cpp' Line: 15 LD_TRACE: (8) In Method: Procedure_Timer_Handler::schedule File: `src/core/procedure/Procedure_Timer_Handler.cpp' Line: 5 Timer id 24 scheduled. LD_TRACE: (8) Out Method: Procedure_Timer_Handler::schedule File: `src/core/procedure/Procedure_Timer_Handler.cpp' Line: 5 LD_TRACE: (8) In Method: Tcp_Connection::send File: `src/core/connector/Tcp_Connection.cpp' Line: 78 src/core/connector/Tcp_Connection.cpp:92 Sent 4 bytes on: Remote IP 173.6.64.7 , Remote Port 30501 Local Ip 173.6.64.7 Local Port 30000 LD_TRACE: (8) Out Method: Tcp_Connection::send File: `src/core/connector/Tcp_Connection.cpp' Line: 78 SENT=> P_ID: 1646 HEXDUMP 4 bytes 00 00 06 6e ...n LD_TRACE: (8) Out Method: Sample_Procedure::start File: `src/apps/procedure/Sample_Procedure.cpp' Line: 15 LD_TRACE: (8) Out Method: Procedure_Executor::handle_timeout File: `src/apps/executor/Procedure_Executor.cpp' Line: 67 LD_TRACE: (4) In Method: Tcp_Handler::handle_input File: `src/core/connector/Tcp_Handler.cpp' Line: 38 src/core/connector/Tcp_Handler.cpp:43 Received 4 bytes LD_TRACE: (4) Out Method: Tcp_Handler::handle_input File: `src/core/connector/Tcp_Handler.cpp' Line: 38 LD_TRACE: (4) In Method: Tcp_Handler::handle_output File: `src/core/connector/Tcp_Handler.cpp' Line: 73 src/core/connector/Tcp_Handler.cpp:78 Successfully dequeued messageLD_TRACE: (4) In Method: AP_TCP_Connection::handle File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 119 LD_TRACE: (4) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 src/core/procedure/Procedure_Pool.cpp:44 Found procedure for id: 1646 LD_TRACE: (4) Out Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 FOUND PROCEDURE FOR ID: 1646 LD_TRACE: (4) In Method: Sample_Procedure::handle File: `src/apps/procedure/Sample_Procedure.cpp' Line: 53 RECV<= P_ID: 1646 HEXDUMP 4 bytes 00 00 06 6e ...n LD_TRACE: (4) In Method: Access_Point::unsubscribe File: `src/apps/network_element/Access_Point.cpp' Line: 196 src/apps/network_element/Access_Point.cpp:199 UNSUBCRIBING: 1646 LD_TRACE: (4) In Method: AP_TCP_Connection::unsubscribe File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 99 src/apps/connector/AP_TCP_Connection.cpp:103 UNSUBCRIBING: 1646 LD_TRACE: (4) In Method: Procedure_Pool::remove_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 25 REMOVING: 1646 LD_TRACE: (4) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 src/core/procedure/Procedure_Pool.cpp:44 Found procedure for id: 1646 LD_TRACE: (4) Out Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 Removed procedure : 1646 LD_TRACE: (4) Out Method: Procedure_Pool::remove_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 25 src/apps/connector/AP_TCP_Connection.cpp:108 UnSubscribed sample type procedureLD_TRACE: (4) Out Method: AP_TCP_Connection::unsubscribe File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 99 LD_TRACE: (4) Out Method: Access_Point::unsubscribe File: `src/apps/network_element/Access_Point.cpp' Line: 196 LD_TRACE: (4) In Method: Procedure_Timer_Handler::cancel File: `src/core/procedure/Procedure_Timer_Handler.cpp' Line: 31 Timer id 24 cancelled. LD_TRACE: (4) Out Method: Procedure_Timer_Handler::cancel File: `src/core/procedure/Procedure_Timer_Handler.cpp' Line: 31 DELETING PROCEDURE: 1646 LD_TRACE: (4) Out Method: Sample_Procedure::handle File: `src/apps/procedure/Sample_Procedure.cpp' Line: 53 LD_TRACE: (4) Out Method: AP_TCP_Connection::handle File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 119 src/core/connector/Tcp_Handler.cpp:91 Successfully send message block to connectorLD_TRACE: (4) Out Method: Tcp_Handler::handle_output File: `src/core/connector/Tcp_Handler.cpp' Line: 73 LD_TRACE: (4) In Method: Procedure_Timer_Handler::handle_timeout File: `src/core/include/Procedure_Timer_Handler.h' Line: 37 LD_TRACE: (4) In Method: Sample_Procedure::handle_timeout File: `src/apps/procedure/Sample_Procedure.cpp' Line: 41 LD_TRACE: (4) Out Method: Sample_Procedure::handle_timeout File: `src/apps/procedure/Sample_Procedure.cpp' Line: 41 LD_TRACE: (4) Out Method: Procedure_Timer_Handler::handle_timeout File: `src/core/include/Procedure_Timer_Handler.h' Line: 37 LD_TRACE: (8) In Method: Procedure_Executor::handle_timeout File: `src/apps/executor/Procedure_Executor.cpp' Line: 67 LD_TRACE: (8) In Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) Out Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) In Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) Out Method: Access_Points::next File: `src/apps/network_element/Access_Points.cpp' Line: 48 LD_TRACE: (8) In Method: Sample_Procedure::Sample_Procedure File: `src/apps/procedure/Sample_Procedure.cpp' Line: 9 LD_TRACE: (8) Out Method: Sample_Procedure::Sample_Procedure File: `src/apps/procedure/Sample_Procedure.cpp' Line: 9 LD_TRACE: (8) In Method: Access_Point::subscribe File: `src/apps/network_element/Access_Point.cpp' Line: 181 LD_TRACE: (8) In Method: AP_TCP_Connection::subscribe File: `src/apps/connector/AP_TCP_Connection.cpp' Line: 81 LD_TRACE: (8) In Method: Procedure_Pool::add_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 5 FIND CALL FROM ADD LD_TRACE: (8) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 41 Segmentation fault (core dumped) // STACK TRACE (gdb) where #0 0x00000000 in ?? () #1 0x000ce15c in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEclERKS2_ (this=0x187548, x=@0x16d2a0) at /vob/wibb_test/tools/cots/boost/boost/multi_index/mem_fun.hpp:60 #2 0x000ce0f8 in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEclIPS2_EEiRKT_ (this=0x187548, x=@0x1345b0) at /vob/wibb_test/tools/cots/boost/boost/multi_index/mem_fun.hpp:55 #3 0x000ce368 in _ZN5boost11multi_index6detail18ordered_index_findINS1_18ordered_index_nodeINS1_15index_node_baseIP9ProcedureEEEENS0_13const_mem_funIS5_iXadsrS5_NKS5_2idEvEEEiSt4lessIiEEEPT_SE_RKT0_RKT1_RKT2_ (header=0x134598, key=@0x187548, x=@0xfe407618, comp=@0x187549) at /vob/wibb_test/tools/cots/boost/boost/multi_index/detail/ord_index_ops.hpp:65 #4 0x000cd6b0 in _ZNK5boost11multi_index6detail13ordered_indexINS0_13const_mem_funI9ProcedureiXadsrS4_NKS4_2idEvEEESt4lessIiENS1_9nth_layerILi1EPS4_NS0_10indexed_byINS0_14ordered_uniqueINS0_3tagI16procedure_id_tagN4mpl_2naESF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_EES5_SF_EESF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_EESaIS9_EEENS_3mpl6v_itemISD_NSL_7vector0ISF_EELi0EEENS1_18ordered_unique_tagEE4findIiEENS1_14index_iteratorINS1_18ordered_index_nodeINS1_15index_node_baseIS9_EEEEEERKT_ (this=0x187548, x=@0xfe407618) at /vob/wibb_test/tools/cots/boost/boost/multi_index/ordered_index.hpp:376 #5 0x00064af0 in Procedure_Pool::find_by_id (this=0x187540, _id=1647) at src/core/procedure/Procedure_Pool.cpp:42 #6 0x0006462c in Procedure_Pool::add_by_id (this=0x187540, _procedure=0x173cd0) at src/core/procedure/Procedure_Pool.cpp:8 #7 0x00078268 in AP_TCP_Connection::subscribe (this=0x19c3a0, _procedure=0x173cd0) at src/apps/connector/AP_TCP_Connection.cpp:84 #8 0x00069b78 in Access_Point::subscribe (this=0x166728, _type=@0x12fc30, _procedure=0x173cd0) at src/apps/network_element/Access_Point.cpp:184 #9 0x000762e4 in Procedure_Executor::handle_timeout (this=0x139ee0, _time=@0xfe407930, _procedure=0x0) at src/apps/executor/Procedure_Executor.cpp:79 #10 0xff2c1940 in ACE_Event_Handler_Handle_Timeout_Upcall<ACE_Recursive_Thread_Mutex>::timeout () from /vob/wibb_test/tools/cots/ACE_5.5/ace/libACE.so.5.5.0 #11 0xff26f2e4 in ACE_TP_Reactor::handle_timer_events () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #12 0xff26f160 in ACE_TP_Reactor::dispatch_i () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #13 0xff26eff8 in ACE_TP_Reactor::handle_events () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #14 0xff254e0c in ACE_Reactor::run_reactor_event_loop () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #15 0x00074b30 in Executor_Reactor::svc (this=0x139f58) at src/apps/executor/Executor_Reactor.cpp:22 #16 0xff2668dc in ACE_Task_Base::svc_run () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #17 0xff266cb0 in ACE_Thread_Adapter::invoke_i () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #18 0xff266c1c in ACE_Thread_Adapter::invoke () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #19 0xff216d50 in ace_thread_adapter () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #20 0xfe8db730 in _thread_start () from /usr/lib/libthread.so.1 #21 0xfe8db730 in _thread_start () from /usr/lib/libthread.so.1 Previous frame identical to this frame (corrupt stack?) (gdb) Priyank -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Wednesday, May 10, 2006 12:05 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! Patel Priyank-PPATEL1 ha escrito: > Hi Joaquin, > > Seems the problem was happening when I call add and my add method > tries to first find out whether that id is already present in > container or not. It is not during remove method call. (My hunch is that the problem will randomly show at various locations, please keep on reading.) > I was concentrating on wrong portion of the code before. Anyways, I > have changed and put some print out in code also at the end I have > included output that comes. I have changed container to ordered index > as you have said, but seems to be the same problem. This is a very valuable piece of information, and increases my suspicions that the problem lies in your code rather than in B.MI: hashed and ordered indices share almost no code at all, so if the problem persists after switching the index type it's probably because the error lies outside the library. Of course, I might be wrong. > It seems that it is core dumping on following line: > > bool Procedure_Pool::find_by_id(Procedure * _procedure) { > LD_TRACE("Procedure_Pool::find_by_id"); > ACE_ASSERT(_procedure != 0); > ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); > Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id ()); > ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != > procedure_by_id_.end()); } > > Please let me know if I am doing something wrong here. Also, let me > know if you need any more information. Please see debug output at the > end of the email. I was consiering two possible causes for the crash in my previous post (leaving out the possibility of a bug in B.MI): 1. Procedure id inadvertently changed. 2. Procedure object deleted before having been removed from the Procedure_Pool. The fact that the crash is now happening in find seems to rule out 1, because inconsistent id's might lead to wrong results in a query, but in no case to a core dump. So, I'd say you are somehow deleting Procedure objects without removing them before from the Procedure_Pool. Maybe you can try to check this as follows: If you can locate all the places in your code where a Procedure object is deleted, i.e expressions of the form: delete p; // p is a Procedure * try instrumenting *all of them* with the following check: if(p != 0){ // Get the pool. I guess you've got some API to do this. Procedure_Hashed_Pool* pool=...; // Since we're deleting p, it musn't still be in pool! assert(pool->find_by_id(p->id()) == 0); } delete p; Do you get an assertion? If so, here's your bug. Please report back. If this doesn't clear up the problem we can explore some other paths. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[BGL] "undirected" edges in a directed graph
by Fernando Cacciola 10 May '06

10 May '06

Hi people, I'm interfacing an algorithm to a data structure via the BGL (that is, I'm presenting the DS as a BGL graph along with various property maps) My data structure is the so-called Halfedge Data Structure (HDS) used in geometric modeling. If the faces of the HDS are not considered, a HDS is a form of Planar Directed Graph (PDG) with the particularity that for any two adjacent vertices p and q, there is an edge from p to q and an opposite edge from q to p. Obtaining the "opposite" edge of any edge is O(1) The structure is called HalfedgeDS because there is always a pair of "Joint Opposite Directed Edges", called halfedges, between p and q : p->q and q->p. Any HDS can be mapped as a BGL graph by simply specializing graph_traits and the global functions accordingly. It just needs as an extension an "opposite_edge" operation. With the "opposite_edge" extension this works like a charm, but there is still one small thing that is natural in the HDS that I'm not sure how to best map to the BGL: Since between any two adjacent vertices p and q there are exactly 2 joint opposite directed edges (that is, two halfedges): p->q and q->p, there is always a very well defined UNDIRECTED view of the HDS: simply considering an arbitraty one of each of the two joint opposite directed edges between any two adjacent vertices. Any edge here (which is a directed edge) can be used an "undirected" edge due to the availability of the opposite_edge() operation. There is at least one operation that needs such an undirected view of the HDS: iterate (not traverse but iterate) all "edges" of the HDS (not "halfedges"). This is of course possible with an ordinary dgraph but much more expensive as it requires the algorithm to filter out halfedges whose opposite was already iterated. Typical instances of a HDS store opposite halfedges pairwise, thus, iterating over all halfedges but stepping 2 at a time, iterates over "undirected edges" very efficienty. This requires a special iterator that is different from the halfedge iterator (and is tyipically provided by HDS models). >From a concept POV I would say that a HDS is a new BGL graph concept. It would call it a "JODE" Graph instead of a "HDS" Graph becasue in the HDS jargon an "edge" is a pair of "halfedges" while in the BGL an "edge" is the actual edge (a directed edge in this case). Such a JODE Graph concept would include the "opposite_edge" operation and the definition of "undirected_edge_iterator", which would iterate over 1 out of the 2 opposite halfedges (Joint Opposite Directed Edges), along with the "undirected_edges" accesor. So far so good... nut I have a problem: where do I put the "undirected_edge_iterator" type?? AFAICT I cannot add an additional type to graph_traits, right? Is subclassing graph_traits a good alternative? Or is there a better way? TIA -- Fernando Cacciola SciSoft http://fcacciola.50webs.com/

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Hi Joaquin, I delete procedure in only two places. And as follows in handle_timeout and handle methods. And I grepped my trace output and handle_timeout never called. So all deletion will be only in one place called "handle" method of that procedure itself. I am going to try it out the changes you mentioned. This is just to let you know how I create and delete procedure objects. Thanks Priyank // PROCEDURE and PROCEDURE DELETER #include "../../procedure/Sample_Procedure.h" int Sample_Procedure::ID = 1000; Sample_Procedure::Sample_Procedure (Access_Point * _ap, int _recv_timer): ap_(_ap), state_(Procedure_State_Enum::INITIAL), type_(Procedure_Type_Enum::SAMPLE_TYPE), recv_timer_(5), recv_timer_handler_(new Procedure_Timer_Handler(recv_timer_)) { LD_TRACE("Sample_Procedure::Sample_Procedure"); id_ = ++Sample_Procedure::ID; } int Sample_Procedure::start() { LD_TRACE("Sample_Procedure::start"); // Create fake message to send char data[4]; memcpy(data, &id_, 4); boost::scoped_ptr<ACE_Message_Block> mb(new ACE_Message_Block(4, ACE_Message_Block::MB_DATA, 0, data)); mb->wr_ptr(4); // end creating fake message // schedule timer for incoming message recv_timer_handler_->schedule(this); // start thread that sends out message after certain interval // send link continuity status request Connection * ap_tcp = (Connection*) ap_->connection(Connection_Type_Enum::AP_TCP); if (ap_tcp) { if (ap_tcp->send(mb) != 0) { ACE_ERROR ((LD_ERROR, "%N:%l Error in sending data.\n")); return -1; } ACE_DEBUG((LM_INFO, "SENT=> P_ID: %d ", id_)); ACE_HEX_DUMP((LM_INFO, data, 4)); } } void Sample_Procedure::handle_timeout() { LD_TRACE("Sample_Procedure::handle_timeout"); // update statistic for failed procedure // REALLY IMPORTANT // MAKE SURE TO DO FOLLOWING // remove this object from connection/s pool // cancel receive handler // delete this object delete this; } int Sample_Procedure::handle(boost::shared_ptr<ACE_Message_Block> _msg_block) { LD_TRACE("Sample_Procedure::handle"); // Log data first ACE_DEBUG((LM_INFO, "RECV<= P_ID: %d ", id_)); ACE_HEX_DUMP((LM_INFO, _msg_block->rd_ptr(), 4)); // update statistic for passed procedure // REALLY IMPORTANT // MAKE SURE TO DO FOLLOWING // remove this object from connection/s pool ap_->unsubscribe(Connection_Type_Enum::AP_TCP, this); // cancel receive timer handler recv_timer_handler_->cancel(); // delete this object. Executor will not delete this object since it will not // go out of the scope untill it's total execution duration finishes, So // delete the procedure as soon as it is done executing to release memory // Also, receive timer handler will be deleted once this object gets deleted // so do not delete that explicitly ACE_DEBUG((LM_DEBUG, "DELETING PROCEDURE: %d\n", this->id())); delete this; } // PROCECURE GENERATOR #include "../include/Procedure_Executor.h" #include "../include/Duration_Timer_Handler.h" #include "../include/Executor_Reactor.h" Procedure_Executor::Procedure_Executor ( const Procedure_Type_Enum& _type, int _starting_sleep, int _hr, int _min, int _sec, int _iterations, int _interval) : procedure_type_(_type), starting_sleep_(_starting_sleep), hr_(_hr), min_(_min), sec_(_sec), duration_(0), num_iterations_(_iterations), interval_(_interval), duration_timer_handler_(0) { LD_TRACE("Procedure_Executor::Procedure_Executor"); // check assertion to make sure proper data is supplied ACE_ASSERT(Procedure_Type_Enum::locate(_type) == true); ACE_ASSERT(hr_ >= 0); ACE_ASSERT(min_ >= 0); ACE_ASSERT(sec_ >= 0); ACE_ASSERT(num_iterations_ > 0); ACE_ASSERT(interval_ > 0); // convert this duration in second duration_ += (60*60*hr_); duration_ += (60*min_); duration_ += sec_; ACE_DEBUG((LM_DEBUG, "%N:%l Duration to run this procedure: %d seconds.\n", duration_)); // convert this duration in millisecond unsigned long milli_sec = interval_ * 1000; // find out sleep time (interval time divided by number of iterations) sleep_ = (unsigned long) (milli_sec / num_iterations_); ACE_DEBUG((LM_DEBUG, "%N:%l Procedure %s will run every %d milliseconds.\n", _type.to_string().c_str(), sleep_)); // create new reactor reactor_.reset(new Executor_Reactor()); // create duration timer handler duration_timer_handler_.reset(new Duration_Timer_Handler(duration_)); } int Procedure_Executor::start() { LD_TRACE("Procedure_Executor::start"); // sleep for starting period time if (starting_sleep_ != 0) { ACE_OS::sleep(starting_sleep_); } // TODO: Might require some change to use high resolution timer stopwatch and // based on that value we might have to sleep more (ofcourse less is not possible.) // start up the reactor reactor_->activate(); // We have registered it recursively so that every time sleep_ will expire, // handle_time of this method will be called ACE_Time_Value * atv1 = new ACE_Time_Value(0, sleep_ * 1000); reactor_->get_ace_reactor().schedule_timer(this, 0, *atv1, *atv1); // start time for duration also, and pass this pointer to that object, that object // should call back stop() method of this class one duration is expires and we will stop // running this procedure duration_timer_handler_->schedule(this, &(reactor_->get_ace_reactor())); // return success return 0; } Procedure_Executor::~Procedure_Executor() { LD_TRACE("Procedure_Executor::~Procedure_Executor"); } int Procedure_Executor::handle_timeout(const ACE_Time_Value &_time, const void * _procedure) { LD_TRACE("Procedure_Executor::handle_timeout"); // select access point Access_Point * ap = (Access_Point*) (Loader_Config::getInstance()->get_aps()->next()); if (ap == 0) { Loader_Config::getInstance()->get_aps()->reset(); ap = (Access_Point*) (Loader_Config::getInstance()->get_aps()->next()); } // create procedure based on procedure type specified if (procedure_type_ == Procedure_Type_Enum::SAMPLE_TYPE) { // create procedure Sample_Procedure * procedure = new Sample_Procedure(ap, 5); // subscribe to related connections ap->subscribe(Connection_Type_Enum::AP_TCP, procedure); // call start of that procedure procedure->start(); } // return success, this will keep this handler in register for further calls return 0; } int Procedure_Executor::stop() { LD_TRACE("Procedure_Executor::stop"); // stop the reactor reactor_->stop(); // remove duration handler from reactor reactor_->get_ace_reactor().remove_handler(duration_timer_handler_.get(), ACE_Event_Handler::TIMER_MASK); // remove this from reactor reactor_->get_ace_reactor().remove_handler(this, ACE_Event_Handler::TIMER_MASK); // return success return 0; } -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Wednesday, May 10, 2006 12:05 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! Patel Priyank-PPATEL1 ha escrito: > Hi Joaquin, > > Seems the problem was happening when I call add and my add method > tries to first find out whether that id is already present in > container or not. It is not during remove method call. (My hunch is that the problem will randomly show at various locations, please keep on reading.) > I was concentrating on wrong portion of the code before. Anyways, I > have changed and put some print out in code also at the end I have > included output that comes. I have changed container to ordered index > as you have said, but seems to be the same problem. This is a very valuable piece of information, and increases my suspicions that the problem lies in your code rather than in B.MI: hashed and ordered indices share almost no code at all, so if the problem persists after switching the index type it's probably because the error lies outside the library. Of course, I might be wrong. > It seems that it is core dumping on following line: > > bool Procedure_Pool::find_by_id(Procedure * _procedure) { > LD_TRACE("Procedure_Pool::find_by_id"); > ACE_ASSERT(_procedure != 0); > ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); > Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id ()); > ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != > procedure_by_id_.end()); } > > Please let me know if I am doing something wrong here. Also, let me > know if you need any more information. Please see debug output at the > end of the email. I was consiering two possible causes for the crash in my previous post (leaving out the possibility of a bug in B.MI): 1. Procedure id inadvertently changed. 2. Procedure object deleted before having been removed from the Procedure_Pool. The fact that the crash is now happening in find seems to rule out 1, because inconsistent id's might lead to wrong results in a query, but in no case to a core dump. So, I'd say you are somehow deleting Procedure objects without removing them before from the Procedure_Pool. Maybe you can try to check this as follows: If you can locate all the places in your code where a Procedure object is deleted, i.e expressions of the form: delete p; // p is a Procedure * try instrumenting *all of them* with the following check: if(p != 0){ // Get the pool. I guess you've got some API to do this. Procedure_Hashed_Pool* pool=...; // Since we're deleting p, it musn't still be in pool! assert(pool->find_by_id(p->id()) == 0); } delete p; Do you get an assertion? If so, here's your bug. Please report back. If this doesn't clear up the problem we can explore some other paths. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Ok..let me try that out... Thanks a lot, Priyank -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Wednesday, May 10, 2006 12:05 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! Patel Priyank-PPATEL1 ha escrito: > Hi Joaquin, > > Seems the problem was happening when I call add and my add method > tries to first find out whether that id is already present in > container or not. It is not during remove method call. (My hunch is that the problem will randomly show at various locations, please keep on reading.) > I was concentrating on wrong portion of the code before. Anyways, I > have changed and put some print out in code also at the end I have > included output that comes. I have changed container to ordered index > as you have said, but seems to be the same problem. This is a very valuable piece of information, and increases my suspicions that the problem lies in your code rather than in B.MI: hashed and ordered indices share almost no code at all, so if the problem persists after switching the index type it's probably because the error lies outside the library. Of course, I might be wrong. > It seems that it is core dumping on following line: > > bool Procedure_Pool::find_by_id(Procedure * _procedure) { > LD_TRACE("Procedure_Pool::find_by_id"); > ACE_ASSERT(_procedure != 0); > ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); > Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id ()); > ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != > procedure_by_id_.end()); } > > Please let me know if I am doing something wrong here. Also, let me > know if you need any more information. Please see debug output at the > end of the email. I was consiering two possible causes for the crash in my previous post (leaving out the possibility of a bug in B.MI): 1. Procedure id inadvertently changed. 2. Procedure object deleted before having been removed from the Procedure_Pool. The fact that the crash is now happening in find seems to rule out 1, because inconsistent id's might lead to wrong results in a query, but in no case to a core dump. So, I'd say you are somehow deleting Procedure objects without removing them before from the Procedure_Pool. Maybe you can try to check this as follows: If you can locate all the places in your code where a Procedure object is deleted, i.e expressions of the form: delete p; // p is a Procedure * try instrumenting *all of them* with the following check: if(p != 0){ // Get the pool. I guess you've got some API to do this. Procedure_Hashed_Pool* pool=...; // Since we're deleting p, it musn't still be in pool! assert(pool->find_by_id(p->id()) == 0); } delete p; Do you get an assertion? If so, here's your bug. Please report back. If this doesn't clear up the problem we can explore some other paths. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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getting name of function from boost::function
by chun ping wang 10 May '06

10 May '06

Hmm i have a question, are there ways to get names of the function from boost::function.. example i have void printfuncname(boost::function<void(int)> func) { do some code to print its name. } int main() { boost::function<void(int)> voidint voidint = &somefunc; printfuncname(func); } Thanks...

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by JOAQUIN LOPEZ MU?Z 10 May '06

10 May '06

Patel Priyank-PPATEL1 ha escrito: > Hi Joaquin, > > Seems the problem was happening when I call add and my add > method tries to first find out whether that id is already > present in container or not. It is not during remove method > call. (My hunch is that the problem will randomly show at various locations, please keep on reading.) > I was concentrating on wrong portion of the code > before. Anyways, I have changed and put some print out in > code also at the end I have included output that comes. I > have changed container to ordered index as you have said, but > seems to be the same problem. This is a very valuable piece of information, and increases my suspicions that the problem lies in your code rather than in B.MI: hashed and ordered indices share almost no code at all, so if the problem persists after switching the index type it's probably because the error lies outside the library. Of course, I might be wrong. > It seems that it is core dumping on following line: > > bool Procedure_Pool::find_by_id(Procedure * _procedure) > { > LD_TRACE("Procedure_Pool::find_by_id"); > ACE_ASSERT(_procedure != 0); > ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); > Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id ()); > ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); > return (it != procedure_by_id_.end()); > } > > Please let me know if I am doing something wrong here. Also, > let me know if you need any more information. Please see debug > output at the end of the email. I was consiering two possible causes for the crash in my previous post (leaving out the possibility of a bug in B.MI): 1. Procedure id inadvertently changed. 2. Procedure object deleted before having been removed from the Procedure_Pool. The fact that the crash is now happening in find seems to rule out 1, because inconsistent id's might lead to wrong results in a query, but in no case to a core dump. So, I'd say you are somehow deleting Procedure objects without removing them before from the Procedure_Pool. Maybe you can try to check this as follows: If you can locate all the places in your code where a Procedure object is deleted, i.e expressions of the form: delete p; // p is a Procedure * try instrumenting *all of them* with the following check: if(p != 0){ // Get the pool. I guess you've got some API to do this. Procedure_Hashed_Pool* pool=...; // Since we're deleting p, it musn't still be in pool! assert(pool->find_by_id(p->id()) == 0); } delete p; Do you get an assertion? If so, here's your bug. Please report back. If this doesn't clear up the problem we can explore some other paths. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Hi Joaquin, Sometime also I get following message when I run. I have pure virtual method in Procedure.h file but I have overridden in my Sample_Procedure.h file and implemented there. But still I am getting error relating pure virtual method call. Thanks Priyank // PROCEDURE HEADER #ifndef PROCEDURE_H #define PROCEDURE_H #include <boost/utility.hpp> #include <boost/shared_ptr.hpp> #include <ace/Message_Block.h> #include <ace/Task.h> #include "Procedure_State_Enum.h" #include "Procedure_Type_Enum.h" #include "Loader_Trace.h" class Procedure : boost::noncopyable { public: /** * Virtual destructor. */ virtual Procedure::~Procedure() { } /** * Stats this procedure. * @return Success of failure status of start */ virtual int start() = 0; /** * Handles this message block. Here we can not use scoped pointer since * we have to use release() method that does more than just deleting the * memory allocated. * @param _msg_block Message block to handler by procedure. * @return Indicates success or failure */ virtual int handle(boost::shared_ptr<ACE_Message_Block> _msg_block) = 0; /** * Returns state of the procedure. * @return Success or failure of the procedure. */ virtual const Procedure_State_Enum& state() const = 0; /** * Sets state of the procedure. * @param state to set */ virtual void state(const Procedure_State_Enum& _state) = 0; /** * Id for registration with connection. * @return Id that is used for registration in subscriber. */ virtual int id() const = 0; /** * Returns type of the procedure. * @return type of the procedure. */ virtual const Procedure_Type_Enum& procedure_type() const = 0; /** * This method will be called whenever procedure timed out for incoming * message. Each procedure will register to appropriate reactor (global for now) using * Procedure Timer Handler class and that class will forward the time out method back * to procedure once time out happens. * @param Indicates where timed out handled successfully or not */ virtual void handle_timeout() = 0; }; #endif // SAMPLE PROCEDURE HEADER #ifndef SAMPLE_PROCEDURE_H #define SAMPLE_PROCEDURE_H #include <boost/utility.hpp> #include <boost/scoped_ptr.hpp> #include <ace/Auto_Event.h> #include <ace/Message_Block.h> #include "../../../../core/include/Procedure.h" #include "../../../../core/include/Connection.h" #include "../../../../core/include/Procedure_Timer_Handler.h" #include "../../../../core/include/Logger.h" #include "../../../apps/include/Access_Point.h" class Sample_Procedure : public Procedure { public: /** * Constructor. * @param _ap Access point associated with this procedure. * @param _wait_timer Wait period for receiving message * may not require for real procedure */ Sample_Procedure (Access_Point * _ap, int _recv_timer); /** * Start method will be called when this procedure is activated. */ virtual int start(); /** * Returns state this procedure. * @return Success or failure of the procedure. */ virtual const Procedure_State_Enum& state () const { return state_; } /** * Sets state of the procedure. * @param state to set */ virtual void state(const Procedure_State_Enum& _state) { state_ = _state; } /** * Returns id for this procedure. This has to be unique id * for the procedure. */ virtual int id () const { return id_; } /** * Returns type of the procedure. * @return type of the procedure. */ virtual const Procedure_Type_Enum& procedure_type() const { return type_; } /** * This method will be called whenever procedure timed out for incoming * message. Each procedure will register to appropriate reactor (global for now) using * Procedure Timer Handler class and that class will forward the time out method back * to procedure once time out happens. */ virtual void handle_timeout(); /** * Handles this message block. Here we can not use scoped pointer since * we have to use release() method that does more than just deleting the * memory allocated. * @param _msg_block Message block to handler by procedure. * @return Indicates success or failure */ virtual int handle(boost::shared_ptr<ACE_Message_Block> _msg_block); static int ID; private: /** * Access point for which the procedure is related to. * This is just a temporary storage. User has to pass * each time procedure is created. */ Access_Point* ap_; /** * State of this procedure. */ Procedure_State_Enum state_; /** * State of the procedure. */ Procedure_Type_Enum type_; /** * Wait period to wait. */ int recv_timer_; /** * Procedure timer handler. */ boost::scoped_ptr<Procedure_Timer_Handler> recv_timer_handler_; /** * Created static for this samle procedure. Might be regular * data member for real procedure. */ int id_; }; #endif Thanks, Priyank LD_TRACE: (8) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 54 PROCEDURE TO FIND: 1548 pure virtual method called Abort (core dumped) (gdb) where #0 0xfe8d9764 in __sigprocmask () from /usr/lib/libthread.so.1 #1 0xfe8ce978 in _resetsig () from /usr/lib/libthread.so.1 #2 0xfe8ce118 in _sigon () from /usr/lib/libthread.so.1 #3 0xfe8d1158 in _thrp_kill () from /usr/lib/libthread.so.1 #4 0xfea4b9dc in raise () from /usr/lib/libc.so.1 #5 0xfea358fc in abort () from /usr/lib/libc.so.1 #6 0xfeb61208 in __cxxabiv1::__terminate (handler=0xfea357f4 <abort>) at ../../../../gcc-3.3/libstdc++-v3/libsupc++/eh_terminate.cc:47 #7 0xfeb61244 in std::terminate () at ../../../../gcc-3.3/libstdc++-v3/libsupc++/eh_terminate.cc:57 #8 0xfeb61744 in __cxa_pure_virtual () at ../../../../gcc-3.3/libstdc++-v3/libsupc++/pure.cc:50 #9 0x000ce1d8 in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEcl ERKS2_ () #10 0x000ce174 in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEcl IPS2_EEiRKT_ () #11 0x000ce3e4 in _ZN5boost11multi_index6detail18ordered_index_findINS1_18ordered_index_no deINS1_15index_node_baseIP9ProcedureEEEENS0_13const_mem_funIS5_iXadsrS5_ NKS5_2idEvEEEiSt4lessIiEEEPT_SE_RKT0_RKT1_RKT2_ () #12 0x000cd72c in _ZNK5boost11multi_index6detail13ordered_indexINS0_13const_mem_funI9Proce dureiXadsrS4_NKS4_2idEvEEESt4lessIiENS1_9nth_layerILi1EPS4_NS0_10indexed _byINS0_14ordered_uniqueINS0_3tagI16procedure_id_tagN4mpl_2naESF_SF_SF_S F_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_EES5_SF_EESF_SF_SF_SF_SF_SF_ SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_SF_EESaIS9_EEENS_3mpl6v_itemISD_NSL_ 7vector0ISF_EELi0EEENS1_18ordered_unique_tagEE4findIiEENS1_14index_itera torINS1_18ordered_index_nodeINS1_15index_node_baseIS9_EEEEEERKT_ () #13 0x00064d78 in Procedure_Pool::find_by_id () #14 0x00064650 in Procedure_Pool::add_by_id () #15 0x000783d4 in AP_TCP_Connection::subscribe () #16 0x00069d64 in Access_Point::subscribe () #17 0x00076450 in Procedure_Executor::handle_timeout () #18 0xff2c1940 in ACE_Event_Handler_Handle_Timeout_Upcall<ACE_Recursive_Thread_Mutex>::tim eout () from /vob/wibb_test/tools/cots/ACE_5.5/ace/libACE.so.5.5.0 #19 0xff26f2e4 in ACE_TP_Reactor::handle_timer_events () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #20 0xff26f160 in ACE_TP_Reactor::dispatch_i () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 ---Type <return> to continue, or q <return> to quit---q Quit (gdb) quit // METHOD bool Procedure_Pool::find_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id()); ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != procedure_by_id_.end()); }

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Hi Joaquin, Seems the problem was happening when I call add and my add method tries to first find out whether that id is already present in container or not. It is not during remove method call. I was concentrating on wrong portion of the code before. Anyways, I have changed and put some print out in code also at the end I have included output that comes. I have changed container to ordered index as you have said, but seems to be the same problem. It seems that it is core dumping on following line: bool Procedure_Pool::find_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id()); ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != procedure_by_id_.end()); } Please let me know if I am doing something wrong here. Also, let me know if you need any more information. Please see debug output at the end of the email. Thanks Priyank #ifndef PROCEDURE_POOL_H #define PROCEDURE_POOL_H /** * Identifier pool of procedure. This procedure will be un-sorted * hashed index provided by procedures unique id retuned by procedure. * It internally uses boost hashed index for indexing the procedures * in procedure pool. * * @author Priyank Patel * @since Mar 30, 2006 */ #include <boost/multi_index_container.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/config.hpp> #include <boost/utility.hpp> #include <boost/shared_ptr.hpp> #include <boost/multi_index/key_extractors.hpp> #include "Procedure.h" using boost::multi_index_container; using namespace boost::multi_index; /** * Defines tag used for procedure id. */ struct procedure_id_tag { }; class Procedure_Pool: boost::noncopyable { private: /** * Type definition for multi index container. */ typedef multi_index_container< Procedure*, indexed_by< ordered_unique< tag<procedure_id_tag>, const_mem_fun<Procedure, int, &Procedure::id> > > > Procedure_Hashed_Pool; /** * Type definition for indexing based on procedure id tag. */ typedef Procedure_Hashed_Pool::index<procedure_id_tag>::type Procedure_By_Id; public: /** * Constructor. */ Procedure_Pool(): pool_(), procedure_by_id_(pool_.get<procedure_id_tag>()) { } /** * Adds specified procedure in this pool. * It will intenally used procedures id() method to index procedure. * @param _procedure Procedure to be added in this pool * @return Success (0) or Failure (-1) based on addition happened or not */ int add_by_id(Procedure * _procedure); /** * Removes procedure from this pool. * @param _procedure procedure that needs to be removed * @return Success (0) or Failure (1) based on removal happend or not */ int remove_by_id(Procedure * _procedure); /** * Retrieves procedure based on specified id. * @param _id Identifier * @return Procedure Pointer to procedure. Returns 0 if procedure not found */ Procedure * find_by_id(int _id); private: /** * Returns true if procedure is present otherwise returns false. * @param _procedure procedure that needs to found * @return true if found or false if not found */ bool find_by_id(Procedure * _procedure); /** * boost multiindex object that is associated with this pool. */ Procedure_Hashed_Pool pool_; /** * Refernece of pool that is indexed by procedure id tag. */ Procedure_By_Id &procedure_by_id_; }; #endif #include "../include/Procedure_Pool.h" int Procedure_Pool::add_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::add_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "FIND CALL FROM ADD\n")); if (!find_by_id(_procedure)) { // procedure not found procedure_by_id_.insert(_procedure); // debug info ACE_DEBUG((LM_DEBUG, "Added procedure : %d \n", _procedure->id())); // return success return 0; } else { // error ACE_ERROR((LD_ERROR "%N:%l Error in adding procedure : %d \n", _procedure->id())); // return failure return -1; } } int Procedure_Pool::remove_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::remove_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "FIND CALL FROM REMOVE\n")); if (find_by_id(_procedure)) { // procedure found procedure_by_id_.erase(_procedure->id()); ACE_DEBUG((LM_DEBUG, "Removed procedure : %d \n", _procedure->id())); return 0; } else { ACE_ERROR((LD_ERROR "%N:%l Error in removing procedure : %d \n", _procedure->id())); return -1; } } Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); return *it; } ACE_ERROR((LD_ERROR "%N:%l Not able to found procedure for id: %d \n", _id)); // return null return 0; } bool Procedure_Pool::find_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_ASSERT(_procedure != 0); ACE_DEBUG((LM_DEBUG, "PROCEDURE TO FIND: %d\n", _procedure->id())); Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id()); ACE_DEBUG((LM_DEBUG, "AFTER FIND CALL\n")); return (it != procedure_by_id_.end()); } Debug Output: ========== May 10 11:12:49.209 2006@isdbuild1@14739@LM_DEBUG@FIND <mailto:2006@isdbuild1@14739@LM_DEBUG@FIND> CALL FROM ADD May 10 11:12:49.209 2006@isdbuild1@14739@LM_TRACE@LD_TRACE <mailto:2006@isdbuild1@14739@LM_TRACE@LD_TRACE> : (8) In Method: Procedure_Pool::find_by_id File: `src/core/procedure/Procedure_Pool.cpp' Line: 54 May 10 11:12:49.209 2006@isdbuild1@14739@LM_DEBUG@PROCEDURE <mailto:2006@isdbuild1@14739@LM_DEBUG@PROCEDURE> TO FIND: 1320 May 10 11:12:49.759 2006@<local_host>@7239@LM_ERROR@Logging <mailto:2006@<local_host>@7239@LM_ERROR@Logging> Service|closing log daemon at host isdbuild1

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[string_algo] trimming Glib::ustring
by Tim Blechmann 10 May '06

10 May '06

hi all, i was trying to use the boost::trim algorithm with Glib::ustring without success ... not sure, if it's a boost or glibmm problem, though ... does anyone have experience with this? thanks ... tim -- TimBlechmann(a)gmx.de ICQ: 96771783 http://www.mokabar.tk Desperation is the raw material of drastic change. Only those who can leave behind everything they have ever believed in can hope to escape. William S. Burroughs

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Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 10 May '06

10 May '06

Hi Joaquin, Thanks for your response. Let me try to answer as much as I can for your questions. Also, I am looking in more detail today. It most probably problem in my side. 1. Does this happen the first time remove_by_id() is called or after some running time? => No. I am adding/removing data in multiindex container every 10 millisecond. It runs fine for certain time period without problems. Core dump happens after some time or execution (it varies though 1 min to 5 min or so.) 2. When the crash happens, do you have some debugging tool which allows you to inspect the contents of the _procedure variable passed to remove_by_id()? => I only have gdb. But I am going to put some print out statements in remove_by_id() method and see what it receives. 3. Note that Procedure_Pool holds *pointers* to Procedure. Could it be, when remove_by_id() crashes, that the Procedure object pointed to by _procedure is already deleted? Check the unsubscribe() routines and all the other procedures listed in the stack trace. => Sure. Let me do that and will get back to you on this one. 4. Remember we were talking about why you cannot change directly the Procedure internal variables, but instead you have to use the updating mechanisms provided by Boost.MultiIndex, as described at: http://boost.org/libs/multi_index/doc/tutorial.html#ord_updating The original discussion was at http://lists.boost.org/boost-users/2006/04/18814.php Are you respecting this? Could it be you have inadvertently changed some procedure id by calling some member function of Procedure interface? => Yes. At this point I am not changing anything in procedure object that used by multiindex function calls after creating procedure. Let me verify this one too again. 5. You are using hashed indices, try, just for testing purposes, replacing them with ordered indices (in principle, you will only have to change the Procedure_Hashed_Pool typedef) Rerun: does the crash still persist? => Sure let me try this first. I used hashed index to improve performance. But I can change and try it out. Will get back to you On this one too. First I will try this. Thanks a lot for your reply on this one. Really appreciate your help. Thanks Priyank -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of JOAQUIN LOPEZ MU?Z Sent: Tuesday, May 09, 2006 3:35 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] [multi_index] Core dump in multi-index library !! Patel Priyank-PPATEL1 ha escrito: > Hi all, > > I am getting following error in boost multi-index library. I am using > following code to add and remove procedures by id in multi index > container. Can somebody please let me know what might be wrong here? > Really appreciate your quick response on this. [...] Hello Priyank, OK, I've got some questions to ask and some things for you to check. Let's see if we nail the problem down. 1. Does this happen the first time remove_by_id() is called or after some running time? 2. When the crash happens, do you have some debugging tool which allows you to inspect the contents of the _procedure variable passed to remove_by_id()? If so, does the object look OK, or garbled? 3. Note that Procedure_Pool holds *pointers* to Procedure. Could it be, when remove_by_id() crashes, that the Procedure object pointed to by _procedure is already deleted? Check the unsubscribe() routines and all the other procedures listed in the stack trace. 4. Remember we were talking about why you cannot change directly the Procedure internal variables, but instead you have to use the updating mechanisms provided by Boost.MultiIndex, as described at: http://boost.org/libs/multi_index/doc/tutorial.html#ord_updating The original discussion was at http://lists.boost.org/boost-users/2006/04/18814.php Are you respecting this? Could it be you have inadvertently changed some procedure id by calling some member function of Procedure interface? 5. You are using hashed indices, try, just for testing purposes, replacing them with ordered indices (in principle, you will only have to change the Procedure_Hashed_Pool typedef) Rerun: does the crash still persist? Hopefully, some of thes points will shed some more light. Looking fwd to your reporting. On a side note, your code shows a Procedure_Hashed_Pool with only one index, yet you define two views on it, namely pool_ and procedure_by_id_, which are the same. This is at most superfluous, although maybe what you have sent is some reduced form of the original code. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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boost::mpl
by Aleksey Loginov 10 May '06

10 May '06

I got a trouble when used boost::mpl. This code works for std::vector, but fail for std::map (gcc 3.4.2) #include <boost/mpl/apply.hpp> #include <boost/mpl/lambda.hpp> #include <boost/type_traits/is_same.hpp> #include <iostream> #include <vector> #include <map> #include <utility> namespace mpl=boost::mpl; template<typename Pair> struct first { typedef typename Pair::first_type type; }; template<typename Pair> struct second { typedef typename Pair::second_type type; }; int main () { typedef mpl::lambda< std::vector< second< mpl::arg<1> > > > vector; std::cout << boost::is_same< mpl::apply<vector, std::pair<char,int> >::type, std::vector<int> >::value << std::endl; typedef mpl::lambda< std::map< first< mpl::arg<1> >, second< mpl::arg<1> > > > map; std::cout << boost::is_same< mpl::apply<map, std::pair<char,int> >::type, std::map<char,int> >::value << std::endl; return 0; } Simple tests show that problem in std::allocator< std::pair<const Key,Type> > Looks like compiler bug, but may be it's my error. Any thought's how avoid the problem?

1 0

Poll: Are you stuck on an old Boost release due to a defective compiler?
by Nicola Musatti 10 May '06

10 May '06

Hallo, I'm trying to gauge the number of Boost users that are actually using an older version of the libraries because they have to use a compiler that's not supported by more recent versions of the libraries they use. As for myself, I work on a project where Borland's BCB6 is used and we're stuck with Boost 1.31 mostly because more recent versions of uBlas do not work with our compiler. Cheers, Nicola Musatti

5 7

program_options questions
by Roel 10 May '06

10 May '06

Hi, I've been using boost::program_options but I have some questions about it. First: to catch errors that the users makes when specifying command-line options (eg I declared an option to be integer-only but the user specified a string), I surrounded the call to store() by a try/catch block: try { boost::program_options::store( boost::program_options::command_line_parser(argc, argv). options(desc).positional(p).run(), vm); } catch (boost::program_options::invalid_option_value e) { } But now how do I give a meaningfull error message? The what() function of invalid_option_value is private, what other options do I have? Secondly, is there a mechanism to check the relation between options? I have a number of options: -a, -m and -d for add, modify and delete respectively; I want only one of them to be allowed at the same time. Also, when the -a option is specified, the -t and -r options are valid, and only then. Do I have to check all of that manually? Thanks. cheers, roel

2 1

boost serialization compilation and WCHAR
by Brian Budge 10 May '06

10 May '06

Hi all - I'm running into problems building the serialization library with gcc 4.1. I tracked it down to a change in libstdc++ for gcc 4.1 from the gcc 3.x libstdc++. I'm sure there's a bug, but I'm not sure if it is a boost bug, a libstdc++ bug, or a gcc 4.1 bug. boost_1_33_1/boost/config/stdlib/libstdcpp3.hpp says: #if !defined(_GLIBCPP_USE_WCHAR_T) && !defined(_GLIBCXX_USE_WCHAR_T) # define BOOST_NO_CWCHAR # define BOOST_NO_CWCTYPE # define BOOST_NO_STD_WSTRING # define BOOST_NO_STD_WSTREAMBUF #endif and indeed, with the 4.1 compiler, neither define is defined. For 4.1 in file /usr/lib/gcc/i686-pc-linux-gnu/4.1.0/include/g++-v4/i686-pc-linux-gnu/c++config.h I have /* Defined if vfwscanf exists. */ #define _GLIBCXX_HAVE_VFWSCANF 1 /* Defined if vswscanf exists. */ #define _GLIBCXX_HAVE_VSWSCANF 1 /* Defined if vwscanf exists. */ #define _GLIBCXX_HAVE_VWSCANF 1 /* Define to 1 if you have the <wchar.h> header file. */ #define _GLIBCXX_HAVE_WCHAR_H 1 /* Defined if wcstof exists. */ #define _GLIBCXX_HAVE_WCSTOF 1 /* Define to 1 if you have the <wctype.h> header file. */ #define _GLIBCXX_HAVE_WCTYPE_H 1 (no reference to USE_WCHAR_T) and in /usr/lib/gcc/i686-pc-linux-gnu/3.4.5/include/g++-v3/i686-pc-linux-gnu/bits/c++config.h I have // Define if code specialized for wchar_t should be used. #define _GLIBCXX_USE_WCHAR_T 1 my fix would be one of three things: 1) in c++config.h #define _GLIBCXX_USE_WCHAR_T 2) in libstdcpp3.hpp add a test for _GLIBCXX_HAVE_WCHAR_H: #if !defined(_GLIBCPP_USE_WCHAR_T) && !defined(_GLIBCXX_USE_WCHAR_T) && !defined(_GLIBCXX_HAVE_WCHAR_H) # define BOOST_NO_CWCHAR # define BOOST_NO_CWCTYPE # define BOOST_NO_STD_WSTRING # define BOOST_NO_STD_WSTREAMBUF #endif 3) somewhere else #ifdef _GLIBCXX_HAVE_WCHAR_H #define _GLIBCXX_USE_WCHAR_T #endif What do you guys think? Brian

1 1

Re: [Boost-users] [serialization] I can't figure out what I'm doing wrong with xml_oarchive - please help
by Manos Tsagarakis 10 May '06

10 May '06

Hello Robert, Thank you for the quick response. I'm glad you liked the title ... A) I did replace all BOOST_CLASS_EXPORT with BOOST_CLASS_EXPORT_GUID, but the problem with xml persists. It is really difficult for me to figure out what is wrong with xml, as both txt and bin versions are ok. Actually what worries me, is the possibility that the problem with xml somehow will show up in other formats too ... B) I don't use the version numbers at the moment but I added it just for future use. I actually have a couple of questions here. 1) BOOST_CLASS_VERSION has to be in the header file? Can I place it in the cpp file? 2) Please correct me If I'm wrong: I don't use BOOST_CLASS_VERSION so that all classes have version number assignment set to 0. I also don't use BOOST_SERIALIZATION_SPLIT_MEMBER for now. Later on, I add some members, so that the class version must change. I simply add BOOST_CLASS_VERSION(..., 1) and split serialize to save/load at that time. Previously saved data files are not affected as long as version info is handled correctly by my code. Is that correct? C) I avoid using templated code in CTCDataBase for as long as the core data that must be serialized evolve, in order to avoid frequently modification of the most included header file TC_database.h. That meens almost recompile all, and that takes time. Thank you for the suggestion any way. I'll keep it in mind. To be honest, I did try to use export feature of templates bug no luck ... D) I re-attach a couple of header files to this post and I kindly ask you to take a look at the implementation and tracking level for template class fem::CPropRepository implementation_level< fem::CPropRepository<T, SZ> > and tracking_level< fem::CPropRepository<T, SZ> >, and one utilization of it at the other header. Should it be so? Do I need it? And also is it possible that using this CPropRepository stuff (especially with MFC CString) breaks the xml code? E) After adding all headers of the serialize library compilation takes a lot more time. Are there any guidelines by you on that? I hope I'm not encroaching your time... Thank you again, Emmanuil Tsagarakis >> -----Original Message----- >> From: boost-users-bounces(a)lists.boost.org >> [mailto:boost-users-bounces@lists.boost.org] On Behalf Of >> Robert Ramey >> Sent: Friday, May 05, 2006 8:36 AM >> To: boost-users(a)lists.boost.org >> Subject: Re: [Boost-users] [boost-users] [serialization] >> I can't figure outwhatI'm doing wrong with xml_oarchive - >> please help >> >> LOL - I liked the title. >> >> I've taken a very quick look at your code and files. >> >> a) I'm a little suspicious of including a ":" character >> as the GUID for a class. I think that might be an issue. >> Try replacing >> >> BOOST_CLASS_EXPORT(fem::CTCSoil); >> >> with >> >> BOOST_CLASS_EXPORT_GUID(fem::CTCSoil, "fem_CTCSoil"); >> >> You'll have to double check the exact syntax. >> >> b) You've set version numbers to 1 but I don't see the >> version numbers used in the deserializations. Version >> number assignment is only necessary if you're going to >> use the version numbers and they are not equal to 0. >> >> c) A minor suggestion - not important here but interesting anyway. >> In fem_boost_serialize.cpp Use templates to shorten the code. >> >> template<class Archive> >> void CTCDataBase::boost_serialize_open(const char* filename) { >> try { >> std::ifstream ifs(filename); >> assert(ifs.good()); >> Archive ia(ifs); >> >> ia >> BOOST_SERIALIZATION_NVP(m_lstSoils); >> ia >> BOOST_SERIALIZATION_NVP(m_lstBrickWalls); >> ia >> BOOST_SERIALIZATION_NVP(CTCFooting::s_bspSoil); >> ia >> BOOST_SERIALIZATION_NVP(CTCFrame::s_bspBrickWall); >> } >> catch (const boost::archive::archive_exception& e) { >> e; >> } >> } >> >> and >> template<class Archive> >> void CTCDataBase::boost_serialize_saveconst char* filename) { >> try { >> std::ofstream ofs(filename); >> assert(ofs.good()); >> Archive oa(ofs); >> >> oa << BOOST_SERIALIZATION_NVP(m_lstSoils); >> oa << BOOST_SERIALIZATION_NVP(m_lstBrickWalls); >> oa << BOOST_SERIALIZATION_NVP(CTCFooting::s_bspSoil); >> oa << BOOST_SERIALIZATION_NVP(CTCFrame::s_bspBrickWall); >> } >> catch (const boost::archive::archive_exception& e) { >> e; >> } >> } >> >> void main() >> { >> fill_with_build_in(); >> boost_serialize_save<boost::archive::text_oarchive>("boost >> _serialize.txt"); >> boost_serialize_save<boost::archive::binary_oarchive>("boo >> st_serialize.bin"); >> boost_serialize_save<boost::archive::xml_oarchive>("boost_ >> serialize.xml"); >> >> // some time later ... >> boost_serialize_open<boost::archive::text_oarchive>("boost >> _serialize.txt"); >> boost_serialize_open<boost::archive::binary_oarchive>("boo >> st_serialize.bin"); >> boost_serialize_open<boost::archive::xml_oarchive>("boost_ >> serialize.xml"); >> } >> >> Robert Ramey >> >> TOL mtsagara wrote: >> >> Hi to all, >> >> >> >> This is my very first post to boost-users! I've been >> using a couple >> >> of boost libraries for a while (shared_ptr & bind >> mostly). Write now >> >> we are in the process of transforming a project based on MFC >> >> collections, (with objects derived from CObject), to >> STL, and doing >> >> some search for a library that will allow object >> persistence the way >> >> MFC does, the obvious solution was boost::serialize. >> As I'm a newbie >> >> in mpl style code the first impression was terrifying! >> But after >> >> reading the documentation and experimenting a lot, I >> did manage to >> >> start using boost::serialize. In fact there is no need >> to be familiar >> >> with mpl. The library is excellent - an exemplary >> work, thank you >> >> Robert Ramey! >> >> >> >> Now my problem is with xml files. I can write a couple >> of classes >> >> both in txt and binary files. But I can't write the >> very same data in >> >> xml format. I believe I followed all guidelines but I >> had no luck ... >> >> :( >> >> >> >> The scenario in pseudo code is this: >> >> >> >> >> >> >> ////////////////////////////////////////////////////////// >> /////////// >> >> / >> >> // file fem.h >> >> #include <boost/archive/...> >> >> #include <boost/serialize/...> >> >> >> >> namespace fem { >> >> >> >> class CTCBase >> >> { >> >> ... >> >> }; >> >> typedef boost::shared_ptr<CTCBase> CBSPBase typedef >> >> std::list<CBSPBase> CBSPBaseList >> >> >> >> >> >> >> >> class CTCSoil >> >> { >> >> ... >> >> }; >> >> typedef boost::shared_ptr<CTCSoil> CBSPSoil typedef >> >> std::list<CBSPSoil> CBSPSoilList >> >> >> >> >> >> >> >> class CTCBrickWall >> >> { >> >> ... >> >> }; >> >> typedef boost::shared_ptr<CTCBrickWall> CBSPBrickWall typedef >> >> std::list<CBSPBrickWall> CBSPBrickWallList >> >> >> >> >> >> >> >> // list of soils >> >> CBSPSoilList s_lstSoils; >> >> // list of Brick Walls >> >> CBSPBrickWallList s_lstBrickWalls; >> >> // initial soil for each new foundation beam (also >> contained in above >> >> list) CBSPSoil s_bspSoil; // initial brick wall on >> each beam (also >> >> contained in above list) CBSPBrickWall s_bspBrick; } >> >> >> >> BOOST_CLASS_VERSION(fem::CTCBase, 1); >> >> BOOST_CLASS_VERSION(fem::CTCSoil, 1); >> >> BOOST_CLASS_VERSION(fem::CTCBrickWall, 1); >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> ////////////////////////////////////////////////////////// >> /////////// >> >> / >> >> // file fem.cpp >> >> >> >> #include "fem.h" >> >> #include <boost/serialization/export.hpp> >> >> >> >> >> >> BOOST_IS_ABSTRACT(fem::CTCBaseObj); >> >> BOOST_CLASS_EXPORT(fem::CTCSoil); >> >> BOOST_CLASS_EXPORT(fem::CTCBrickWall); >> >> >> >> void fill_with_build_in() >> >> { >> >> ... >> >> } >> >> >> >> >> >> void main() >> >> { >> >> fill_with_build_in(); >> >> boost_serialize_save_txt("boost_serialize.txt"); >> >> boost_serialize_save_bin("boost_serialize.bin"); >> >> boost_serialize_save_xml("boost_serialize.xml"); >> >> >> >> >> >> // some time later ... >> >> boost_serialize_open_txt("boost_serialize.txt"); >> >> boost_serialize_open_bin("boost_serialize.bin"); >> >> boost_serialize_open_xml("boost_serialize.xml"); >> >> } >> >> >> >> >> >> >> >> The xml save & open functions are in file >> fem_boost_serialize.cpp >> >> >> >> I attached the 3 files produced this way. I can also >> read back txt & >> >> binary versions. I'm wondering if somebody - hopefully >> Robert Ramey! >> >> - can tell me just by examining the output files, >> where should I look >> >> for the problem. Or do I have to debug the code line >> by line and see >> >> what wend wrong? It seems something is wrong with the >> very first >> >> shared_ptr serialization . >> >> >> >> I include some - not stand alone I'm afraid - source >> code files with >> >> this message just in case someone might take a look at >> them. I can >> >> tell that during the transition period from MFC to STL >> (possibly >> >> after that too), our objects derive from MFC CObject. >> Also at the >> >> moment, we still use MFC CString and not std::string. >> I had to copy >> >> CString to std::string for the serialization to work >> properly. Could >> >> there be a conflict somewhere there? Could it be the >> order in hpp >> >> files are included? >> >> >> >> >> >> Finally I use MS Visual C++ .net 2003 and boost v1.33.1. >> >> >> >> >> >> Thank you in advanced, >> >> >> >> >> >> >> >> Emmanuil Tsagarakis >> >> >> >> >> > >> > >> > >> >> _______________________________________________ >> >> Boost-users mailing list >> >> Boost-users(a)lists.boost.org >> >> http://lists.boost.org/mailman/listinfo.cgi/boost-users >> >> >> >> _______________________________________________ >> Boost-users mailing list >> Boost-users(a)lists.boost.org >> http://lists.boost.org/mailman/listinfo.cgi/boost-users >> >>

3 3

Question about g++'s typeof
by Stephen Gross 09 May '06

09 May '06

I just found out about the typeof feature in g++. I'm trying to use the type returned by a boost::bind invocation. Is there any way to make the following work: =============================== struct A { int foo(); } typedef typeof(boost::bind(A::foo)) my_type; =============================== So far, g++ just seg faults on me. Am I doing something horribly wrong, or is this (more likely) not possible in the first place? Thanks, --Steve Stephen Gross Case Western School of Medicine Cleveland, OH "By Grabthar's hammer, by the sons of Worvan, you shall be avenged." - Dr. Lazarus

5 4

Re: [Boost-users] [multi_index] Core dump in multi-index library !!
by JOAQUIN LOPEZ MU?Z 09 May '06

09 May '06

Patel Priyank-PPATEL1 ha escrito: > Hi all, > > I am getting following error in boost multi-index library. I am > using following code to add and remove procedures by id in multi > index container. Can somebody please let me know what might be > wrong here? Really appreciate your quick response on this. [...] Hello Priyank, OK, I've got some questions to ask and some things for you to check. Let's see if we nail the problem down. 1. Does this happen the first time remove_by_id() is called or after some running time? 2. When the crash happens, do you have some debugging tool which allows you to inspect the contents of the _procedure variable passed to remove_by_id()? If so, does the object look OK, or garbled? 3. Note that Procedure_Pool holds *pointers* to Procedure. Could it be, when remove_by_id() crashes, that the Procedure object pointed to by _procedure is already deleted? Check the unsubscribe() routines and all the other procedures listed in the stack trace. 4. Remember we were talking about why you cannot change directly the Procedure internal variables, but instead you have to use the updating mechanisms provided by Boost.MultiIndex, as described at: http://boost.org/libs/multi_index/doc/tutorial.html#ord_updating The original discussion was at http://lists.boost.org/boost-users/2006/04/18814.php Are you respecting this? Could it be you have inadvertently changed some procedure id by calling some member function of Procedure interface? 5. You are using hashed indices, try, just for testing purposes, replacing them with ordered indices (in principle, you will only have to change the Procedure_Hashed_Pool typedef) Rerun: does the crash still persist? Hopefully, some of thes points will shed some more light. Looking fwd to your reporting. On a side note, your code shows a Procedure_Hashed_Pool with only one index, yet you define two views on it, namely pool_ and procedure_by_id_, which are the same. This is at most superfluous, although maybe what you have sent is some reduced form of the original code. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

1 0

[multi_index] Core dump in multi-index library !!
by Patel Priyank-PPATEL1 09 May '06

09 May '06

Hi all, I am getting following error in boost multi-index library. I am using following code to add and remove procedures by id in multi index container. Can somebody please let me know what might be wrong here? Really appreciate your quick response on this. // HEADER FILE #include <boost/multi_index_container.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/config.hpp> #include <boost/utility.hpp> #include <boost/shared_ptr.hpp> #include <boost/multi_index/key_extractors.hpp> #include "Procedure.h" using boost::multi_index_container; using namespace boost::multi_index; /** * Defines tag used for procedure id. */ struct procedure_id_tag { }; class Procedure_Pool: boost::noncopyable { private: /** * Type definition for multi index container. */ typedef multi_index_container< Procedure*, indexed_by< hashed_unique< tag<procedure_id_tag>, const_mem_fun<Procedure, int, &Procedure::id> > > > Procedure_Hashed_Pool; /** * Type definition for indexing based on procedure id tag. */ typedef Procedure_Hashed_Pool::index<procedure_id_tag>::type Procedure_By_Id; public: /** * Constructor. */ Procedure_Pool(): pool_(), procedure_by_id_(pool_.get<procedure_id_tag>()) { } /** * Adds specified procedure in this pool. * It will intenally used procedures id() method to index procedure. * @param _procedure Procedure to be added in this pool * @return Success (0) or Failure (-1) based on addition happened or not */ int add_by_id(Procedure * _procedure); /** * Removes procedure from this pool. * @param _procedure procedure that needs to be removed * @return Success (0) or Failure (1) based on removal happend or not */ int remove_by_id(Procedure * _procedure); /** * Retrieves procedure based on specified id. * @param _id Identifier * @return Procedure Pointer to procedure. Returns 0 if procedure not found */ Procedure * find_by_id(int _id); private: /** * Returns true if procedure is present otherwise returns false. * @param _procedure procedure that needs to found * @return true if found or false if not found */ bool find_by_id(Procedure * _procedure); /** * boost multiindex object that is associated with this pool. */ Procedure_Hashed_Pool pool_; /** * Refernece of pool that is indexed by procedure id tag. */ Procedure_By_Id &procedure_by_id_; }; // IMPLEMENTATION #include "../include/Procedure_Pool.h" int Procedure_Pool::add_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::add_by_id"); ACE_ASSERT(_procedure != 0); if (!find_by_id(_procedure)) { // procedure not found procedure_by_id_.insert(_procedure); // debug info ACE_DEBUG((LM_DEBUG, "Added procedure : %d \n", _procedure->id())); // return success return 0; } else { // error ACE_ERROR((LD_ERROR "%N:%l Error in adding procedure : %d \n", _procedure->id())); // return failure return -1; } } int Procedure_Pool::remove_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::remove_by_id"); ACE_ASSERT(_procedure != 0); if (find_by_id(_procedure)) { // procedure found procedure_by_id_.erase(_procedure->id()); ACE_DEBUG((LM_DEBUG, "Removed procedure : %d \n", _procedure->id())); return 0; } else { ACE_ERROR((LD_ERROR "%N:%l Error in removing procedure : %d \n", _procedure->id())); return -1; } } Procedure * Procedure_Pool::find_by_id(int _id) { LD_TRACE("Procedure_Pool::find_by_id"); Procedure_By_Id::iterator it = procedure_by_id_.find(_id); if (it != procedure_by_id_.end()) { ACE_DEBUG((LM_DEBUG, "%N:%l Found procedure for id: %d \n", _id)); return *it; } ACE_ERROR((LD_ERROR "%N:%l Not able to found procedure for id: %d \n", _id)); // return null return 0; } bool Procedure_Pool::find_by_id(Procedure * _procedure) { LD_TRACE("Procedure_Pool::find_by_id"); ACE_ASSERT(_procedure != 0); Procedure_By_Id::iterator it = procedure_by_id_.find(_procedure->id()); return (it != procedure_by_id_.end()); } // CORE STACK TRACE (gdb) where #0 0x00000000 in ?? () #1 0x000d0008 in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEcl ERKS2_ () #2 0x000cffa4 in _ZNK5boost11multi_index13const_mem_funI9ProcedureiXadsrS2_NKS2_2idEvEEcl IPS2_EEiRKT_ () #3 0x000cf4dc in _ZN5boost11multi_index6detail12hashed_indexINS0_13const_mem_funI9Procedu reiXadsrS4_NKS4_2idEvEEENS_4hashIiEESt8equal_toIiENS1_9nth_layerILi1EPS4 _NS0_10indexed_byINS0_13hashed_uniqueINS0_3tagI16procedure_id_tagN4mpl_2 naESH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_EES5_SH_SH_EESH _SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_SH_EESaISB_EEENS_3mp l6v_itemISF_NSN_7vector0ISH_EELi0EEENS1_17hashed_unique_tagEE5eraseEi () #4 0x00066774 in Procedure_Pool::remove_by_id () #5 0x0007a4ac in AP_TCP_Connection::unsubscribe () #6 0x0006bd5c in Access_Point::unsubscribe () #7 0x00082988 in Sample_Procedure::handle () #8 0x0007a89c in AP_TCP_Connection::handle () #9 0x0005f380 in Tcp_Handler::handle_output () #10 0xff257ca8 in ACE_Select_Reactor_Notify::dispatch_notify () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #11 0xff26f424 in ACE_TP_Reactor::handle_notify_events () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #12 0xff26f188 in ACE_TP_Reactor::dispatch_i () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #13 0xff26eff8 in ACE_TP_Reactor::handle_events () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #14 0xff254e0c in ACE_Reactor::run_reactor_event_loop () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #15 0x000f3848 in ACE_Reactor::run_event_loop () #16 0x000f37d8 in Global_Reactor::svc () #17 0xff2668dc in ACE_Task_Base::svc_run () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #18 0xff266cb0 in ACE_Thread_Adapter::invoke_i () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #19 0xff266c1c in ACE_Thread_Adapter::invoke () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #20 0xff216d50 in ace_thread_adapter () at /mot/proj/ivtools/ppatel1/ACE_wrappers/ace/String_Base.inl:32 #21 0xfe8db730 in _thread_start () from /usr/lib/libthread.so.1 #22 0xfe8db730 in _thread_start () from /usr/lib/libthread.so.1 Thanks Priyank

1 0

boos::shmem vs vc6
by Alex 09 May '06

09 May '06

Hi Guys, I'm wondering whether shmem can be used under vc6 compiler, trying to compile expamples provided within the library package I receive a full bunch of errors looking like: boost_1_33_1\boost\shmem\detail\workaround.hpp(70) : error C2011: 'random_it<void>' : 'struct' type redefinition boost_1_33_1\boost\shmem\detail\workaround.hpp(81) : error C2011: 'random_it<void>' : 'struct' type redefinition boost_1_33_1\boost\shmem\detail\workaround.hpp(92) : error C2011: 'random_it<void>' : 'struct' type redefinition boost_1_33_1\boost\shmem\shmem_fwd.hpp(154) : error C2954: template definitions cannot nest boost_1_33_1\boost\shmem\shmem_fwd.hpp(154) : error C2951: template declarations are only permitted at global or namespace scope boost_1_33_1\boost\shmem\shmem_fwd.hpp(155) : error C2226: syntax error : unexpected type 'IndexType' boost_1_33_1\boost\shmem\shmem_fwd.hpp(156) : error C2143: syntax error : missing '>' before ';' boost_1_33_1\boost\shmem\shmem_fwd.hpp(156) : error C2059: syntax error : '<end Parse>' boost_1_33_1\boost\shmem\shmem_fwd.hpp(162) : error C2955: 'flat_map_index' : use of class template re etc... However with VC7 everything seems to be fine. Your comments and ideas are highly appreciated. Regards, Alex

2 2

mpl, apply, placeholders
by Kiuhnm 09 May '06

09 May '06

I am just a beginner so my question could be very stupid. Please be patient. What is wrong with the following code? It should be clear enough what I am trying to do. >>> #include <iostream> #include <boost/mpl/int.hpp> #include <boost/mpl/apply.hpp> #include <boost/mpl/plus.hpp> int main() { using namespace boost::mpl; // ... typedef apply< plus< _, int_<10> >, int_<1> >::type t; std::cout << typeid(t).name() << std::endl; typedef apply< plus< _, int_<10> >, _ > t2; typedef apply< t2, int_<1> >::type res; // ??? std::cout << typeid(res).name() << std::endl; } <<< Kiuhnm -- View this message in context: http://www.nabble.com/mpl%2C-apply%2C-placeholders-t1379886.html#a3705111 Sent from the Boost - Users forum at Nabble.com.

4 7

Re: [Boost-users] [statechart] Event handlers and state reusage
by Oliver.Kowalke＠qimonda.com 09 May '06

09 May '06

>Tim Milward wrote: >> Johan Nilsson wrote: >>> 1. For a state, is it possible to specify a method that will be >>> called when an event with no defined handlers is received? >> >> Interesting question. Can all events inherit from a common base class, >> to which a state could define a (default) reaction, and override this >> with reactions to specific event sub-classes? > >Should be possible from my point of view. Not sure how the framework would >handle that even though it sounds reasonable. It's a bit limiting though, >and should be possible have support for in the library. By default statechart ignores a event with no handlers in the statemachine. Statechart allows to catch the event by adding following function to your state_machine class: void unconsumed_event( sc::event_base const& ev) { ... } Oliver

2 1

How to pass memory range to functions?
by Olaf van der Spek 09 May '06

09 May '06

Hi, I've got a lot of functions (compression, encryption, hashing, encoding, etc) that work on a memory range. I wrote my own class that has constructors for void*, void* void*, size_t std::string& and that automatically reinterpret_cast to unsigned char*. But I'm wondering, is there a better way to do this? Boost.Range looked appriopriate but it seemed it didn't support this scenario.

1 0

documentation for bjam sub-variants
by Russell Hind 09 May '06

09 May '06

Can some one point me to the page that details the sub-variants (such as <runtime-link> and <threading>) etc that are available to pass to bjam when building boost. I have found the main bjam page that gives a few examples but it doesn't list all the options and their meanings. Thanks Russell

2 2

[operators] loss of performance
by Brian Budge 09 May '06

09 May '06

Hi all - I just tried out the operators library for the first time today. I was quite happy with how easily it helped me implement my test class. Unfortunately, I'm running into some performance issues, in particular with operator +. The interesting thing is that the new operator += is actually faster than my old += by about a factor of 2, but my operator + is slower than my old + by a factor of nearly 10! I'm new here, and not really sure how much code is appropriate to post to the list, so here's a minimal rundown: -------------------------------------------------------------------------- Old code: template<typename real> Vector3<real> operator + (const Vector3<real> &a, const Vector3<real> &b); template<typename real> class Vector3 { protected: real m_v[3]; . . friend Vector3 operator +<> (const Vector3 &a, const Vector3 &b); }; template<typename real> inline Vector3<real> operator + (const Vector3<real> &a, const Vector3<real> &b){ Vector3<real> t; t[0] = a[0] + b[0]; t[1] = a[1] + b[1]; t[2] = a[2] + b[2]; return t; } ------------------------------------------------------------------------------------------------- New code (note that the new code is templatized on size, and that my instantiations were of size 3 to match the above code): template<typename T, unsigned int S> class vec : boost::additive< vec<T, S> , boost::multiplicative< vec<T, S>, T > > { private: typedef unsigned int uint; typedef const T &const_reference; typedef T &reference; private: boost::array<T,S> m_v; template<typename U> vec &operator += (const vec<U,S> &t){ for(uint i = 0; i < S; ++i){ m_v[i] += t.m_v[i]; } return *this; } }; Any ideas how to increase the performance of the new code here? A factor of 10 makes it seem like I am just missing something important. Thanks, Brian

5 6

[boost][test] - BOOST_FIXTURE_TEST_SUITE, BOOST_FIXTURE_TEST_CASE clarification
by Ed Johnson 09 May '06

09 May '06

In 1.33.1 release, is the following true? BOOST_FIXTURE_TEST_SUITE( suite_name, F ); //not supported BOOST_FIXTURE_TEST_CASE( test_name, F ); //not supported Thanks, Ed

2 6

Building boost on Mac OS 10.4
by Zokirov, Umed 08 May '06

08 May '06

Hi there, Has anyone successfully built Boot 1.33.1 on Moac OS X 10.4? In my case it fails to build test - related libs. I fugured out the issue with two-level namespacing, however waas not successful with specific linker settings to solve them Perhaps, boost-build mailing list is better to ask, nevertheless, I would suppose some of the users actually built boost. Umed

2 1

Inconsistency between boost::bind and boost::lambda::bind
by Gerardo Lamastra 08 May '06

08 May '06

Hello everybody, I've started to use the functional programming facilities offered by boost, and they're really impressive. To begin with, I've started using both; I've seen however, that when I #include both <boost/bind.hpp> and <boost/lambda/bind.hpp> I must use full namespace names to address lambda placeholders. In other words, instead of writing for_each(container.begin(), container.end(), cout << _1 << constant('\n')); I've to write for_each(container.begin(), container.end(), cout << boost::lambda::_1 << boost::lambda::constant('\n')); also if I've written a using boost::lambda declaration; I know, I can simplify this using a namespace alias, but I was trying to keep the code less clobber as I can, because it has to be used for teaching/example purposes. So, my first question would be: where could I find an exhaustive comparison between these two facilities? And, is there any indication on what to prefer, also related to future development and/or inclusion in C++ standards (If I remember well, boost::lambda has been proposed in tr1?) The second question points at a small inconsistency that I believe I've found while doing some experiments: boost::bind and boost::lambda::bind offer similar construct, but the former works while the latter fails in the example included below. I'm using boost_1_33_1, with g++ -v (provided below) Target: i586-mandriva-linux-gnu Configured with: ../configure --prefix=/usr --libexecdir=/usr/lib --with-slibdir=/lib --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --disable-checking --enable-languages=c,c++,ada,f95,objc,java --host=i586-mandriva-linux-gnu --with-system-zlib --enable-long-long --enable-__cxa_atexit --enable-clocale=gnu --disable-libunwind-exceptions --enable-java-awt=gtk --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --enable-gtk-cairo --disable-libjava-multilib Thread model: posix gcc version 4.0.1 (4.0.1-5mdk for Mandriva Linux release 2006.0) The situation is the following: if I try to create a nullary lamnda function with boost::lambda::bind() like this: generate_n(inserter(v, v.begin()), 10, boost::lambda::bind<Slave*>( boost::lambda::new_ptr<Slave>(),*this) ); the compiler fails to compile: it tries to pass the this pointer as a const reference somehow, and then it fails claiming that a Slave(const Master& m) cannot be found; If I try to add one, it fails with a similar error. If I substitute the boost::lambda::bind() with a boost::bind(), it compiles & works perfectly. Thanks for the attention, -Gerardo Lamastra ------------------------------------------------------------------------- #include <set> #include <algorithm> #include <iterator> #include <iostream> #include <boost/lambda/lambda.hpp> #include <boost/lambda/construct.hpp> #include <boost/lambda/bind.hpp> #include <boost/bind.hpp> using namespace std; using namespace boost::lambda; class Master; struct Slave { static int globalId; Master& master; int id; Slave(Master& m) : master(m), id(++globalId) {}; }; int Slave::globalId = 0; class Master { struct Builder { typedef Slave* result_type; Slave* operator()(Master& master) { return new Slave(master); }; }; static Slave* build(Master& master) { return new Slave(master); } public: void print(set<Slave*> s) { for_each(s.begin(), s.end(), (cout << constant("S: ") << (boost::lambda::_1) ->* &Slave::id) << '\n' ); } void f1() { /* This is the most trivial thing I've tried, but I need to write builder explicitely; */ set<Slave*> v; generate_n(inserter(v, v.begin()), 10, boost::bind(Builder(),*this) ); print(v); } void f2() { /* A more compact, but substantially identical form */ set<Slave*> v; generate_n(inserter(v, v.begin()), 10, boost::bind(&Master::build,*this) ); print(v); } void f3() { /* Does not work; it seems that the object passed to the compiler is a const Master& instead of just a Master&, it is like that the boost::lambda::bind() adds a const where that is not required... I tried to substitute the Master& in the Slave() constructor with a const Master& but it does not work either */ /* set<Slave*> v; generate_n(inserter(v, v.begin()), 10, boost::lambda::bind(&Master::build,*this) ); print(v); */ } void f4() { /* The same issue applies here... * This has been my original experiment, which * motivated all this trouble... */ /* set<Slave*> v; generate_n(inserter(v, v.begin()), 10, boost::lambda::bind<Slave*>( boost::lambda::new_ptr<Slave>(),*this) ); print(v); */ } void f5() { /* A work-around that I come up with, * mixing boost::bind && boost::lambda::new_ptr */ set <Slave*> v; generate_n(inserter(v, v.begin()), 10, boost::bind<Slave*>(boost::lambda::new_ptr<Slave>(),*this) ); print(v); } }; int main() { Master m; cout << "F1: " << endl; m.f1(); cout << "F2: " << endl; m.f2(); cout << "F5: " << endl; m.f5(); } -------------------------------------------------------------------- CONFIDENTIALITY NOTICE This message and its attachments are addressed solely to the persons above and may contain confidential information. If you have received the message in error, be informed that any use of the content hereof is prohibited. Please return it immediately to the sender and delete the message. Should you have any questions, please contact us by replying to webmaster(a)telecomitalia.it. Thank you www.telecomitalia.it --------------------------------------------------------------------

3 2

[date_time] What's the proper way to convert local to UTC?
by Scott 08 May '06

08 May '06

Note: Reposting in hopes of getting an answer. c_local_adjustor has the static method "utc_to_local" to easily convert to local time based on the machine TZ setting. So I figured it had a utc_from_local or local_to_utc method as well. Neither compiled, so I looked at the header file c_local_time_adjustor.hpp: //! Adjust to / from utc using the C API Yet there is only that one method in the class. Is the missing ability to convert from local to UTC an oversight or is it implemented somewhere else? What's the correct way to do it? Thanks, Scott

1 0

Re: [Boost-users] [shmem] New bugfix version in Boost Vault and sandbox cvs
by bwood 08 May '06

08 May '06

Ion Gaztañaga wrote: >Jan Stetka(e)k dio: >> Yes I understand that I can't use shmem::map and std::map if they are >> both on the global namespace. I've looked at the implementation of the >> std::map header from the STL implementation that is included in vc++ 7.2 >> and that doesn't forward declare std::list in <map>. This is a design >> issue rather than a bug. Why forward declare shmem::list by including it >> in map.hpp when it isn't used? > > >All classes in Shmem include shmem_fwd.hpp or container_fwd.hpp where >Shmem defines default arguments (for example default Less, or Allocator >template parameter). That's why you get the predeclaration of list >including map. Another alternative would be to declare a *_fwd.hpp for >each class defined in Shmem, but you would get a lot of extra headers, >and I would have a lot of work to maintain. > > >Even if I don't include list predeclaration with map, I'm free to use >any Shmem container in any Shmem class (for example, I can implement a >pooled allocator using a list container), so it's likely that a Shmem >class include will include more Shmem classes (predeclarations, or full >declarations). I don't consider it a design error, but a design choice. >What I see dangerous is pushing two namespaces, std, and shmem to the >same context because they have similar classes. An alternative would be >to rename shmem classes like "vector" to "shmem_vector", .... But >weren't namespaces born to allow that? I think this is their intended purpose, but I don't like using them that way. It gets confusing and brevity isn't attained as you have to qualify things. Namespaces support a "let's just agree to disagree" approach that isn't a resolution, but is the best that can be done at times. Do you think this shmem functionality should be integrated with the std containers? In the meantime, I think shmem_vector is better. Does shmem support multi_index_containers? Or, depending on how shmem fits into the picture, should B.MI take the lead in supporting shmem functionality internally? Y'all have more flexibility in the B.MI case as it isn't part of the standard. Brian www.webEbenezer.net

4 4

Re: [Boost-users] Thread-safe smart pointers, hashtables without locking
by Ray Whitmer 08 May '06

08 May '06

> I'd also say the idea of moving a pointer out of the way, and then > using the > flip-gate-count-thing to wait for any 'potentially-using' readers > to finish, > definitely has 'potential'. You would need to show detailed code to > really > be sure. And not to us - to the guys on comp.programming.threads. Thanks. I will plan on pursuing it, then. > Anyhow, if you haven't already, take a look at memory barriers, > and, as a > canonical example, the broken 'double checked locking pattern'. You > can't > do lock free without understanding this stuff. I was somewhat aware of memory ordering and especially compiler reordering, but I need to take another look at it and find the proper set of macros for use in non-kernel code since volatile does not (yet) guarantee hardware behavior between processors. > And you are correct, you can't make { reading the > location of a shared_ptr + incrementing its ref-count } atomic, it > least not > on most processors. Actually, I was not concerned with incrementing the ref count. The flip-gate-count-thing solves, I believe, the problem of reference counts not being up to date all the time. I realize that I still have to prove this, but I do not think it is hard. What worries me more is whether the smart pointer has one or two fields in it, because this affects whether readers find an incomplete/ broken smart pointer as they whiz by. With a single pointer field in it, the load and store are atomic. > I don't think the boost implementation of intrusive_ptr's operator= > () is > atomic, but it could be made to be. shared_ptr has two pointers in it, (one to the shared count, one for the pointer) whereas intrusive_ptr has a single pointer in it (since the count is internal to the referenced class). This means that the shallow bits of shared_ptr are not atomically initialized, whereas those of intrusive_ptr are. An obvious way to solve this would be to make shared_ptr contain a single pointer to a wrapper class that contains both the shared count and a shared pointer, but this adds an unacceptable level of indirection to basic pointer operations. > Your wording of 'much less likely' is scary, and I think similar > wording > made James apprehensive as well. There is no grey - it is black or > white, > thread safe or not. I will have to adjust my language. I tend to use uncertain language both because I consider my knowledge incomplete and because of the lack of a generic standard that guarantees behavior, i.e. the fact that different Linux kernel architectures need different memory barriers, etc. is demonstration of the uncertainty of a general C solution. If I can rely on something like what the Linux kernel relies on, it should not be scary. Behavior needs to be guaranteed on supported platforms, and other platforms need to be detected and fail to compile lock-free or revert to a locking fallback implementation, etc. Ray Whitmer

2 1

Re: [Boost-users] [operators] loss of performance
by Victor A. Wagner Jr. 08 May '06

08 May '06

At 23:05 2006-05-07, you wrote: >Hi all - > >I just tried out the operators library for the first time today. I >was quite happy with how easily it helped me implement my test class. >Unfortunately, I'm running into some performance issues, in particular >with operator +. > >The interesting thing is that the new operator += is actually faster >than my old += by about a factor of 2, but my operator + is slower >than my old + by a factor of nearly 10! > >I'm new here, and not really sure how much code is appropriate to post >to the list, so here's a minimal rundown: > >-------------------------------------------------------------------------- >Old code: > >template<typename real> >Vector3<real> operator + (const Vector3<real> &a, const Vector3<real> &b); > >template<typename real> >class Vector3 { >protected: > real m_v[3]; >.. >.. > friend Vector3 operator +<> (const Vector3 &a, const Vector3 &b); >}; > >template<typename real> >inline Vector3<real> operator + (const Vector3<real> &a, const >Vector3<real> &b){ > Vector3<real> t; > t[0] = a[0] + b[0]; > t[1] = a[1] + b[1]; > t[2] = a[2] + b[2]; > return t; >} > >------------------------------------------------------------------------------------------------- >New code (note that the new code is templatized on size, and that my >instantiations >were of size 3 to match the above code): > >template<typename T, unsigned int S> >class vec > : boost::additive< vec<T, S> > , boost::multiplicative< vec<T, S>, T > > > >{ >private: > typedef unsigned int uint; > typedef const T &const_reference; > typedef T &reference; > >private: > boost::array<T,S> m_v; > > template<typename U> > vec &operator += (const vec<U,S> &t){ > for(uint i = 0; i < S; ++i){ > m_v[i] += t.m_v[i]; > } > return *this; > } >}; > >Any ideas how to increase the performance of the new code here? A >factor of 10 makes it seem like I am just missing something important. you showed us the code that you claim is faster, what do you want us to do? >Thanks, > Brian >_______________________________________________ >Boost-users mailing list >Boost-users(a)lists.boost.org >http://lists.boost.org/mailman/listinfo.cgi/boost-users Victor A. Wagner Jr. http://rudbek.com The five most dangerous words in the English language: "There oughta be a law"

2 1

[date_time] strange warning
by george 08 May '06

08 May '06

hello! try { boost::gregorian::date date_start(boost::gregorian::from_string(start)); boost::gregorian::date date_end(boost::gregorian::from_string(end)); boost::gregorian::date today(boost::gregorian::day_clock::local_day()); if(date_start > date_end || date_start < today || date_end.year() > today.year()) return false; period_=new boost::gregorian::date_period(date_start,date_end); return true; } catch(...) { return false; } .../boost/date_time/constrained_value.hpp: In member function ‘virtual bool Reservation::validation(std::string&)’: .../boost/date_time/constrained_value.hpp:64: warning: ‘year$D34041$value_’ is used uninitialized in this function .../date_time/constrained_value.hpp:64: warning: ‘year$D34041$value_’ is used uninitialized in this function why I get this warning? any idea? thanks

2 2

Re: [Boost-users] [multi_index] const mem_fun serialization bug.
by JOAQUIN LOPEZ MU?Z 08 May '06

08 May '06

----- Mensaje original ----- De: Julien Pervillé <julien.perville(a)free.fr> Fecha: Sábado, Mayo 6, 2006 9:15 pm Asunto: [Boost-users] [multi_index] const mem_fun serialization bug. > Hello boost-users. > > I am writing to report an annoying serialization bug encountered > while developing a project with Boost.multi_index, which is a > wonderfully useful data structure. Thank you Joaquín! > > First a fast overview of my project: [...] > After hunting through the headers, I located the triggered > exception to line 1080 of boost/multi_index/ordered_index.hpp > (line number from boost 1.33) > > Here is the context from the "rearranger" method where the > exception is thrown: > > > 1080 if(position!=x){ In Boost 1.33, tis is actually line 1088. Maybe a typo in your post? Anyway, I don't think this is important. [...] > I am looking forward to test patches and offer my help testing, > so that this little quirk gets solved. Hello Julien, thank you very much for using Boost.MultiIndex and for providing such a detailed bug report, with reproducible test case and all --actually, having the test case has made it easy to spot the problem. This is a bug in B.MI, but it has nothing to do with const_mem_fun. Rather it lies in the serialization loading algorithm. I'd like you to make the following changes in your local copy of B.MI (I'm assuming you've got 1.33 as per what you say in the post): 1. Replace line 80 in boost/multi_index/detail/duplicates_iterator.hpp: if(pred(begin_chunk->value,node->value))advance(); with the following: if(node!=end&&pred(begin_chunk->value,node->value))advance(); This bug was previously spotted by Toby Smith, and it's currently fixed in the CVS version of B.MI, soon to be shipped with Boost 1.34. More details at: http://lists.boost.org/boost-users/2006/01/16710.php 2. Replace the beginning of rearranger() at line 1076 of boost/multi_index/ordered_index.hpp: void rearranger(node_type* position,node_type *x) { node_type* before; if(!position){ ... with the following: void rearranger(node_type* position,node_type *x) { node_type* before; if(!position||comp(key(position->value),key(x->value))){ ... 3. Undo your previous hack which bypassed the archive_exception throw. That's it. I can confirm this makes seri-bug.cpp work OK. Could you please verify whether it also solves the problems in your real project? I'll devote some days to carefully study the issue and, if nothing weird shows, will commit the fix in the CVS HEAD and 1_33_4 branches next week. Please comment your results back. Thanks for reporting, best regards, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

3 2

a problem on boost::asio
by 李慧霸 08 May '06

08 May '06

I'm trying asio on WindowsXPSP2 + VS2003, and I found that there are always some connections established from 127.0.0.1:xxxx to 127.0.0.1:yyyy, is it a bug?

1 0

How to test whether a vertex or edge exists?
by sean yang 08 May '06

08 May '06

I want to add a vertex, which a string as its ID to a graph if a vertex representing such a string does not exist in the graph. Is there a function call to test if a vertex exists in a graph? ----------------------------------------------------------------------- //Here is the simpilfied situation that I want to handle, "IF THERE IS NOT a vertex representing the //string of the current line" is the predicate I want to know typedef adjacency_list<vecS, vecS, directedS, property<vertex_color_t, default_color_type>, property<edge_weight_t, int> > Graph; Graph g(); ifstream infile; infile.open(argv[1]); string line; while( getline(infile, line) ){ if(line.find("Node")!= npos && /*IF THERE IS NOT a vertex representing the string of the current line*/) add_vertex( line, g); } -------------------------------------------------------------------- A related question I want to ask is whether there exist a function call that test whether an edge representing [vertext string("Node1") --> vertext string("Node2") ] exists in a graph. Thanks a lot, Sean _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today - it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/

2 3

A Problem with boost::bind
by Hossein Haeri 07 May '06

07 May '06

Dear all, A fragment of code of mine is like this: template <class Container, size_t i> struct print { ostream& operator () (const Container& c, ostream& out) const { if(out) { typedef typename Container::value_type value_type; typedef print<value_type, i - 1> NewPrint; NewPrint newPrint; for(typename Container::const_iterator j = c.begin(); j != c.end(); ++j) newPrint(*j, out); /*for_each(c.begin(), c.end(), bind(newPrint, _2, out)); //Error!*/ } return out; } }; AFAICS, there should be no harm in replacing that for with the for_each in the comments -- the one is marked with "//Error" I mean, except that "out" which is of type ostream& is not Copy-Constructible, and therefore _2 cannot be used against it. Anybody having a workarounds for that? Doesn't Boost have anything analog to boost::ref which can give me a Copy-Constructible beast? For your reference, you can find the whole program and the compiler error message in the P.S. TIA, --Hossein P.S. #include <iostream> #include <algorithm> #include <iterator> #include <vector> #include <boost/bind.hpp> #include <boost/mem_fn.hpp> using std::ostream; using std::cin; using std::cout; using std::copy; using std::for_each; using std::ostream_iterator; using std::vector; using boost::bind; using boost::mem_fn; template <class Container, size_t i> struct print { ostream& operator () (const Container& c, ostream& out) const { if(out) { typedef typename Container::value_type value_type; typedef print<value_type, i - 1> NewPrint; NewPrint newPrint; /* for(typename Container::const_iterator j = c.begin(); j != c.end(); ++j) newPrint(*j, out); */ for_each(c.begin(), c.end(), bind(newPrint, _2, out)); //Error! } return out; } }; template <class Container> struct print<Container, 1> { ostream& operator () (const Container& c, ostream& out) const { if(out) copy(c.begin(), c.end(), ostream_iterator<typename Container::value_type>(out, " ")); return out; } ostream& DoIt (const Container& c, ostream& out) const { if(out) copy(c.begin(), c.end(), ostream_iterator<typename Container::value_type>(out, " ")); return out; } }; int main() { int a1[] = {1, 2, 3, 4}; const size_t n(sizeof(a1)/sizeof(*a1)); vector<int> v(a1, a1 + n); print<vector<int>, 1> () (v, cout); int a2[n] = {5, 6, 7, 8}; vector<vector<int> > m; m.push_back(v); m.push_back(vector<int>(a2, a2 + n)); print<vector<vector<int> >, 2> () (m, cout); cin.get(); return 0; } Compiler: Default compiler Executing g++.exe... g++.exe "E:\Print.cpp" -o "E:\Print.exe" -I"C:\Dev-Cpp\include\c++" -I"C:\Dev-Cpp\include\c++\mingw32" -I"C:\Dev-Cpp\include\c++\backward" -I"C:\Dev-Cpp\include" -L"C:\Dev-Cpp\lib" C:/Dev-Cpp/include/c++/3.3.1/bits/ios_base.h: In copy constructor ` std::basic_ios<char, std::char_traits<char> >::basic_ios(const std::basic_ios<char, std::char_traits<char> >&)': E:/Print.cpp:33: instantiated from `std::ostream& print<Container, i>::operator()(const Container&, std::ostream&) const [with Container = std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >, unsigned int i = 2]' E:/Print.cpp:72: instantiated from here C:/Dev-Cpp/include/c++/3.3.1/bits/ios_base.h:668: error: ` std::ios_base::ios_base(const std::ios_base&)' is private E:/Print.cpp:33: error: within this context E:/Print.cpp: In member function `std::ostream& print<Container, i>::operator()(const Container&, std::ostream&) const [with Container = std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >, unsigned int i = 2]': E:/Print.cpp:72: instantiated from here E:/Print.cpp:33: error: initializing argument 3 of ` boost::_bi::bind_t<boost::_bi::unspecified, F, typename boost::_bi::list_av_2<A1, A2>::type> boost::bind(F, A1, A2) [with F = print<std::vector<int, std::allocator<int> >, 1>, A1 = boost::arg<2>, A2 = std::basic_ostream<char, std::char_traits<char> >]' C:/Dev-Cpp/include/boost/bind.hpp: At global scope: C:/Dev-Cpp/include/boost/bind.hpp: In instantiation of `boost::_bi::result_traits<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1> >': C:/Dev-Cpp/include/boost/bind/bind_template.hpp:16: instantiated from `boost::_bi::bind_t<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1>, boost::_bi::list2<boost::arg<2>, boost::_bi::value<std::basic_ostream<char, std::char_traits<char> > > > >' E:/Print.cpp:33: instantiated from `std::ostream& print<Container, i>::operator()(const Container&, std::ostream&) const [with Container = std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >, unsigned int i = 2]' E:/Print.cpp:72: instantiated from here C:/Dev-Cpp/include/boost/bind.hpp:62: error: no type named `result_type' in ` struct print<std::vector<int, std::allocator<int> >, 1>' C:/Dev-Cpp/include/boost/bind/bind_template.hpp: In instantiation of `boost::_bi::bind_t<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1>, boost::_bi::list2<boost::arg<2>, boost::_bi::value<std::basic_ostream<char, std::char_traits<char> > > > >': E:/Print.cpp:33: instantiated from `std::ostream& print<Container, i>::operator()(const Container&, std::ostream&) const [with Container = std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > >, unsigned int i = 2]' E:/Print.cpp:72: instantiated from here C:/Dev-Cpp/include/boost/bind/bind_template.hpp:16: error: no type named `type' in `struct boost::_bi::result_traits<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1> >' C:/Dev-Cpp/include/boost/bind/bind_template.hpp:19: error: no type named `type' in `struct boost::_bi::result_traits<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1> >' C:/Dev-Cpp/include/boost/bind/bind_template.hpp:25: error: no type named `type' in `struct boost::_bi::result_traits<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1> >' C:/Dev-Cpp/include/boost/bind/bind_template.hpp:31: error: no type named `type' in `struct boost::_bi::result_traits<boost::_bi::unspecified, print<std::vector<int, std::allocator<int> >, 1> >' C:/Dev-Cpp/include/boost/bind/bind_template.hpp:31: confused by earlier errors, bailing out Execution terminated ___________________________________________________________ Switch an email account to Yahoo! Mail, you could win FIFA World Cup tickets. http://uk.mail.yahoo.com

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Re: [Boost-users] [MULTI_INDEX] intersection algorithm?
by JOAQUIN LOPEZ MU?Z 07 May '06

07 May '06

Guillaume Lazzara ha escrito: > Hello, > > I am currently using multi_index as "set" container > and I wanted to know how to use intersection algorithm. > I tried with the STL interction algorithm but it > crashed. How can I do? Hello Guillaume. In principle, there's nothing preventing multi_index_container's from working with set_intersection. Could you provide a case where the referred to crash shows? Failing that, a little more detailed explanation or some code? Thank you, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[SOC] Applicants -- Please Monitor Google for Comments
by Jeff Garland 07 May '06

07 May '06

Hi All - First let me say that we've had a tremendous response thus far to SOC. Some really excellent applications and ideas. I have high hopes that some very exciting Boost projects will come out of SOC. The reason I'm sending this is that I'm trying to reach out to applicants that may not be aware that proposal feedback is being provided on the SOC website. Please check your proposal for comments. Many of the proposals need additional details. There is no automated email when we add comments to a proposal, so you won't be notified. Goggle is looking into adding this, but it isn't there now. There are enough comments and proposals that it would be impractical for us to ensure that everyone got notified when a comment is added. Thanks, Jeff

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Re: [Boost-users] [shmem] New bugfix version in Boost Vault andsandbox cvs
by JOAQUIN LOPEZ MU?Z 06 May '06

06 May '06

----- Mensaje original ----- De: Ion Gaztañaga <igaztanaga(a)gmail.com> Fecha: Sábado, Mayo 6, 2006 9:51 pm Asunto: Re: [Boost-users] [shmem] New bugfix version in Boost Vault andsandbox cvs > > Or, depending on > > how shmem fits into the picture, should B.MI take the lead in > > supporting shmem functionality internally? Y'all have more > > flexibility in the B.MI case as it isn't part of the standard. > > To be able to support Multi-index in shared memory we would need > to > rewrite it to replace all raw pointers with allocator::pointer > typedefs. > I haven't looked through multiindex code but this can be a big > task. > There is nothing that shmem can do to support multiindex if it > uses raw > pointers. But I think that multiindex and shmem can be a good base > for > in-memory data-bases. > I wholeheartedly agree with you shmem and multi_index should be able to interoperate nicely. My other activities in B.MI, and my rather shallow knowleddge of shmem, prevent me from attacking this task right away, but I'd be happy if some bold Booster could do some analysis/prototype of the changes involved in B.MI for it to work with shmem, so that eventually I can integrate those changes. If someone is up to the task, do count on my support/assitance for matters concerning the inner structure of B.MI. Best regards, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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[serialization] problems with using wide-char archives
by Hilal Shaath 06 May '06

06 May '06

Hello All: The serialization library is one of the best libraries I have used. I used to to serialize a number of files with various sizes, and it works like a charm. However, when I am using the wide-char archives, I get a linking error. Here are the problem specifications: When including : #include "boost/archive/binary_woarchive.hpp" #include "boost/archive/binary_wiarchive.hpp" Or #include "boost/archive/text_woarchive.hpp" #include "boost/archive/text_wiarchive.hpp" And attempt to use them (i.e.) std::map<wstring,size_t> htable; wstring root = L"c:"; findDFF(&htable,&root); std::wofstream ofs("someFile",std::wios::binary); boost::archive::binary_woarchive o(ofs); I get the following linking errors: [ DB3 error LNK2019: unresolved external symbol "public: __thiscall boost::archive::basic_binary_oprimitive<class boost::archive::binary_woarchive,class std::basic_ostream<unsigned short,struct std::char_traits<unsigned short> > >::~basic_binary_oprimitive<class boost::archive::binary_woarchive,class std::basic_ostream<unsigned short,struct std::char_traits<unsigned short> > >(void)" (??1?$basic_binary_oprimitive@Vbinary_woarchive@archive@boost@@V?$basic_ostream@GU?$char_traits@G@std@@@std@@@archive@boost@@QAE@XZ) referenced in function "public: __thiscall boost::archive::binary_woarchive_impl<class boost::archive::binary_woarchive>::~binary_woarchive_impl<class boost::archive::binary_woarchive>(void)" (??1?$ ] If I use the regular archives (binary_oarchive) I don't get any errors, and it runs as a charm! The compiler I am using is VC++ version 7.1/ I would be grateful if some could point me to the reason for this error. Thanks for your help Hilal

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[multi_index] const mem_fun serialization bug.
by Julien Pervillé 06 May '06

06 May '06

Hello boost-users. I am writing to report an annoying serialization bug encountered while developing a project with Boost.multi_index, which is a wonderfully useful data structure. Thank you Joaquín! First a fast overview of my project: I am developing a virtual file system for my internship. In this file system, I have to store user paths which I call "entries". "entries" are associated with another "internal entry" which is the path to the physical target inside the file system. "entries" are also contained in a concept of "directory". To ease up things I store entries in a boost::multi_index with at least 3 indexes: - an unique index to look up user entries. - a non-unique index to do reverse look up (by internal targets). - a non-unique index to do directory listings. The latter is the one that interests us. The "entry" class splits the entry into the "dirname" and "file" parts. A getter function returns a const-reference to "dirname", let's call it "entry::dirname()". To do directory listings efficiently, I define an ordered-non-unique index pointinh to the const-reference returned by the entry.dirname() thanks to a wrapper "mem_fun" named getdirname(). Now comes the bug. To test my file system, I import some existing directories into my file system. When I unload it, I expect that the internal boost::multi_index is serialized and restored properly when I reload the file system program. When working on huge batches of small files, like untaring a linux kernel or copying the thousands of files from /usr/share/doc, I noticed that the import works but reloading the serialized mappings fails with a (for now unexplained but reproducable) boost::serialization::other_exception. After hunting through the headers, I located the triggered exception to line 1080 of boost/multi_index/ordered_index.hpp (line number from boost 1.33) Here is the context from the "rearranger" method where the exception is thrown: > 1080 if(position!=x){ > 1081 /* check the rearrangement is consistent */ > 1082 if(!in_place(x->value,position,Category())){ > 1083 throw_exception( > 1084 archive::archive_exception( > 1085 archive::archive_exception::other_exception)); > 1086 } Since my multi_index works perfectly until I save, I checked that my data is properly serialized. Since I saw no obvious errors, I modified the header to swallow the exception and see what happens. > 1080 if(position!=x){ > 1081 /* check the rearrangement is consistent */ > 1082 if(!in_place(x->value,position,Category())){ > 1083 return; throw_exception( > 1084 archive::archive_exception( > 1085 archive::archive_exception::other_exception)); > 1086 } After this small hack, everything "seems" to work fine but if I do a "find" on my file system some entries appear "missing". They are actually not missing but they were attributed to the wrong directory! And in the wrong parent directory, a lookup says "file not found" when find tries to access it. However, I can still access the entries by naming them explicitely (using the main index, not the dirname one). I investigated and found out that the "dirname" ordered_index (const mem_fun) is not restored properly, even through it is saved correctly. The "entry" and the "target" ordered indexes (member) are restored as intended. However look what happens to the mem_fun "dirname" index: its values are restored in positions that are not a valid binary tree. Actually it is "almost" a binary tree, just some values are wrongly restored. Like a dozen out of 1000 entries, but always the same ones. As a consequence even if my entry::operator<() predicate is proved correct, lookups through the "dirname" index give byzantine results. I tracked down the problem and found a small set of "entries" that are not restored properly and wrote a small example file. Please have a look at the attached source "seri-bug.cpp". The example dumps the contents of a 5 entries multi_index, first by entry and then by "dirname". The displaying is done before serializing to disk and after reloading the mappings. The corruption can then be see by checking the different position inside the dirname index for the "/doc/binutils-doc" entry before and after. Sample run: Original structure dump by dirname, pre serialization. > entry `/' with dirname `'. > entry `/doc' with dirname `'. > entry `/doc/binutils-doc' with dirname `/doc'. > entry `/doc/binutils-doc/ld' with dirname `/doc/binutils-doc'. > entry `/doc/binutils-doc/gas' with dirname `/doc/binutils-doc'. Post serialized loading dump. Notice that the "/doc/binutils-doc" entry was not restored at the correct position. Since the dirnames are not properly sorted in memory, doing a find() by dirname obtains byzantine results (doing a find of "/doc" dirname returns the `/doc/binutils-doc/ld' result instead of the expected `/doc/binutils-doc' entry). > entry `/' with dirname `'. > entry `/doc' with dirname `'. > entry `/doc/binutils-doc/ld' with dirname `/doc/binutils-doc'. > entry `/doc/binutils-doc' with dirname `/doc'. > entry `/doc/binutils-doc/gas' with dirname `/doc/binutils-doc'. Even if this sample triggers the restore anomaly, to see a boost::archive::other_exception one needs more data inside the multi_index, like a few thousand entries. I would really love to see a this bug fixed since it stalls my projects. My c++ template metaprogramming skills aren't very sharp but I think that this bug is a good opportunity to learn some about this subject. I am looking forward to test patches and offer my help testing, so that this little quirk gets solved. Sincerely, Julien Perville Intern, Global Core, Amadeus IT Group.

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adjacency_list and UndirectedGraph in BGL
by sean yang 06 May '06

06 May '06

I am a newbie using BGL and only read a couple of example source code. I have a question about class representing a graph. It seems adjacency_list represent a graph, but it seems there is a class hierarchy (as shown in (2) ) to represent a graph. What is their relationship? (1) adjacency_list can represent a graph, e.g., typedef adjacency_list<vecS, vecS, bidirectionalS, no_property, property<edge_weight_t, float> > Graph; (2) And the online manual give a list of Graph representation. I guess it's a hierarchical class representation. i.e., Graph <--Incidence Graph <--Bidirectional Graph. Am I right? But if so, I did not find the constructor of these classes. Furthermore, this class hierarchy has give a full classification of graph, why is there a adjacency_list representation? Chapter 11. The Boost Graph Interface 1. Graph 2. Incidence Graph 3. Bidirectional Graph 4. Adjacency Graph 5. Vertex List Graph 6. Edge List Graph 7. Vertex and Edge List Graph 8. Mutable Graph 9. Property Graph 10. Mutable Property Graph (3) There is an exmple of UndirectedGraph in the book of "User guide and reference manual" { ... V=3; UndirectedGraph undigraph(V); add_edge(0, undigraph); ..... } is there a way not specifying vertice number when defining an object and dynamically adding vertex when according to user input? i.e, something like UndirectedGraph undigraph( ); while (getline(in, line)){ add_edge(line, undigraph); } _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today - it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/

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[MULTI_INDEX] intersection algorithm?
by Guillaume Lazzara 06 May '06

06 May '06

Hello, I am currently using multi_index as "set" container and I wanted to know how to use intersection algorithm. I tried with the STL interction algorithm but it crashed. How can I do? Thanks in advance, -- Guillaume Lazzara Epita Promo 2008 http://guillaume.lazzara.fr

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Re: [Boost-users] boost::multi_index_container different search key type
by JOAQUIN LOPEZ MU?Z 06 May '06

06 May '06

----- Mensaje original ----- De: bert hubert <bert.hubert(a)netherlabs.nl> Fecha: Miércoles, Mayo 3, 2006 8:15 pm Asunto: [Boost-users] boost::multi_index_container different search key type > Joaquin, list, > > In one of the last issues of the C/C++ User's Journal, Andrei > Alexandrescu described the need for something better than std::map > when using expensive > keys: > [...] > > More on http://www.ddj.com/dept/cpp/184402065 - might this be > something boost::multi_index_container could be made to do? > Hello Bert, I'm glad you asked, because multi_index_container already provides this, and I would dare say in a more powerful fashion. Ordered and hashed indices lookup member functions (find, equal_range, etc.) are overloaded to accept *compatible keys*, which can be used to pass alternate representations of keys in exactly the same manner as described in Andrei's article. Compatible keys are introduced at http://tinyurl.com/rouet and formally described at http://tinyurl.com/hp9j4 (ordered indices) http://tinyurl.com/ze5od (hashed indices) But there is more: in the case of ordered indices, compatible keys need not be in a 1-to-1 relation with the original keys, but can be "coarser", in a sense. An example can help clarify this: Suppose we've got an index ordered by a date, with millisecond precision, then the index is certainly ordered by year; compatible key support can be thus used to perform lookup by year if only we provide the appropriate comparison semantics between full dates and years, so that "year" is a compatible key of "date". Although it might not be apparent, composite keys take full advantage of all of this: * When you pass a tuple to lookup on some composite_key- enabled index, the tuple is *not* the index key_type, but merely a more convenient representation. * Compatible key support (in the "coarser key" sense) is used when you do "partial searches" in which only the first tuple values are specified: see http://tinyurl.com/hdf3q. When Andrei's article first came out, I contacted him to discuss these concepts and the similarities between his ÜberContainers and compatible key support as provided by B.MI: IMHO it is not unusual that these sort of ideas come up recurrently. Thanks for your active interest in Boost.MultiIndex! Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Re: [Boost-users] Thread-safe smart pointers, hashtables
by Gottlob Frege 06 May '06

06 May '06

> Date: Fri, 5 May 2006 14:09:33 -0600 > From: Ray Whitmer <ray(a)personallegal.net> > Subject: Re: [Boost-users] Thread-safe smart pointers, hashtables > without locking > To: boost-users(a)lists.boost.org > Message-ID: <0D5E3BD4-9A5D-4CE2-9040-35500773C190(a)personallegal.net> > Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed > > > The algorithm makes sense, and if all these claims hold then it > > should work, I think. I'm still concerned about step (2), however, > > if only because of the assumption that what you write as a load/ > > store in C++ maps to a load/store in ML. Will it? Always? I ask as > > a non-rhetorical question: does the C++ standard *guarantee* it? > > Because if it doesn't then it seems like a potential problem, but > > maybe I'm being too careful. I'd also say the idea of moving a pointer out of the way, and then using the flip-gate-count-thing to wait for any 'potentially-using' readers to finish, definitely has 'potential'. You would need to show detailed code to really be sure. And not to us - to the guys on comp.programming.threads. If I could answer in the affirmative, I could prove it works and not > have to talk to anyone. I can make a bunch of lesser claims, that of > course fail to add up to the strong claim but make me feel better: > > 3. I have looked at the output of many C compilers and have never > seen a pointer assignment take multiple instructions. The exception > might be if someone used a poorly-written memcpy-like operations to > transfer the contents of a structure byte by byte. A well-written > one takes the respective alignments into account and transfers > aligned 32-bit quantities one-by-one. We are talking about code in a > controlled Hashtable class, it would have to be the "C" compiler > choosing to transfer a class consisting of a single address field > using something other than a single instruction. It doesn't sound > logical to me, but it wouldn't surprise me completely to see it > happen, but I would report it as a compiler bug and expect it to be > addressed even though it is not in the standard. As long as the address of the pointer is properly aligned, it will be atomic. The language doesn't guarantee that (the language doesn't talk about atomic or threads at all - at least not yet), but the processors + compilers tend to guarantee it. HOWEVER! *even if it is atomic*, on a multi-cpu machine each cpu might see memory differently - you need memory barriers to ensure the other cpus see your new pointer value correctly. Think of cpus and memory like harddrive controllers that reorder reads and writes to lessen seeks - the cpu does the same sort of thing with memory - and in doing so, it may reorder the write of your pointer to 'happen' before you expected (because it was near other memory it was writing) and/or read the pointer later than expected (because it optimized other reads into a 'bundle' before the read of your pointer). Anyhow, if you haven't already, take a look at memory barriers, and, as a canonical example, the broken 'double checked locking pattern'. You can't do lock free without understanding this stuff. 4. These issues have to be addressed with the multi-processor cores > becoming more prevalent because they are basic to lock-free > processing, or can C++ accept significant inferiority to Java with > respect to lock-free multiprocessing? see above. Much of it doesn't come for free. For what it is worth, if anyone else thinks the solution is worth a > generic contribution, or is of the opposite opinion that it would not > be generic enough, I would be interested in hearing. I suppose this > sort of question should go to the developers list. I think it would > be much more difficult to implement a table of shared_ptr than it is > for intrusive_ptr, because assigning a shared_ptr is much less likely > to be uninterrupted, leaving other threads with a broken visible > state. There is clearly more detail to discuss as well. > Ray Whitmer Your wording of 'much less likely' is scary, and I think similar wording made James apprehensive as well. There is no grey - it is black or white, thread safe or not. And you are correct, you can't make { reading the location of a shared_ptr + incrementing its ref-count } atomic, it least not on most processors. I'm not sure of the exact implementation of intrusive_ptr, but assuming it is like most, you can make ip1 = ip2; atomic IF ip2 is 'stable', ie guaranteed to not be changing during the assignment. ie ip1 can be read and/or written by other threads "while" the assignment is happening, and you will either get the before state of ip1, or the after state. I don't think the boost implementation of intrusive_ptr's operator=() is atomic, but it could be made to be. Tony

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[BGL] adjacency_list property map selection
by Daniel Mitchell 06 May '06

06 May '06

Are there any plans to replace the property map selection code with a mechanism based on partial specialization? I'm implementing interior property maps for my own graph classes and must decide which approach to use. Partial specialization is elegant, but there's also value in consistency with BGL. D.

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