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[Proto] Splitting AST
by Joel Falcou 03 Mar '09

03 Mar '09

Let's say I want to take an expression involving operators +,-,*,/ and a function split. What I want to do is writing a transform taking such an expression and returning a fusion::vector or list (I guess) of expressions containing all sub-expressions of the original AST only separated on each insatcne of a split call. E.g : Xpr = a+b+split( c*d + split(e-f)); is turned into Xprs = [ a+b+placeholder<1>, c*d+placeholder<2>, e-f]; I guess I should use the State/Data parameters of the transform but i can't get the thing right. Any hints on how to tackle this without losing hairs ? -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

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using boost::filesystem::delete
by Sean Farrow 03 Mar '09

03 Mar '09

Hi: I have a boost::filesystem::wpath object. I need to firstly check if the file exists, and secondly delete and check the file has been deleted. How would I go about this? I've loked at the reference and carn't seem to make sense, are thee any examples of both these functions? Any help apreciated. Sean.

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Installing boost 1.38 in UBUNTU 8.10
by jan acosta 03 Mar '09

03 Mar '09

Hey guys, I am having trouble linking my boost libraries to a program I am trying to install. I need to install boost versions above 1.37 and ubuntu doesn't have packages yet for anything above 1.35. I am trying to install this program: http://webapp.dam.brown.edu/wiki/SciComp/InstallHedgeFromGit I followed the steps in his wiki but I always get this error message: g++ -pthread -shared -Wl,-Bsymbolic-functions build/temp.linux-x86_64-2.5/src/cpp/cuda.o build/temp.linux-x86_64-2.5/src/cpp/bitlog.o build/temp.linux-x86_64-2.5/src/wrapper/wrap_cudadrv.o build/temp.linux-x86_64-2.5/src/wrapper/mempool.o -L/home/supacreative/pool/include/lib -L/usr/local/cuda/lib -lboost_python-gcc41-mt -lcuda -o build/lib.linux-x86_64-2.5/pycuda/_driver.so /usr/bin/ld: cannot find -lboost_python-gcc41-mt collect2: ld returned 1 exit status error: command 'g++' failed with exit status 1 I can't get past this error. I've tried using the export command using: export LD_LIBRARY_PATH=/home/(my username)/pool/lib:$LD_LIBRARY_PATH and I still get the same error message. I even added the library folder into my ld.so.conf.d and ran ldconfig to restart ld, but I still get the same error. Please help. Jan

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Template method applied to template object
by Adrien Chauve 03 Mar '09

03 Mar '09

Hi all, The following lines don't compile with g++ (4.3.2) whereas it's ok with msvc 9. struct Foo { template<class T> unsigned int foo() const { return sizeof(T); } }; struct OtherFoo { template<class T> void f(const T& t) { t.foo<double>(); } }; int main() { Foo foo; OtherFoo other; other.f<Foo>(foo); return 0; } The ouput is : test.cpp: In member function ‘void OtherFoo::f(const T&)’: test.cpp:17: erreur: expected primary-expression before ‘double’ test.cpp:17: erreur: expected `;' before ‘double’ Does anybody know a workaround ? Thanks, Adrien

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Error when trying to build boost 1.38.0 with msvc 8.0
by LPE 03 Mar '09

03 Mar '09

I'm trying to build boost 1.38.0 on Windows, with MSVC 8.0 and bjam 3.1.17, and I get this error : D:\boost_1_38_0>bjam -q -j3 -d+2 --toolset=msvc --build-type=complete Skipping build of: ./headers <build>no in common properties Skipping build of: ./headers <build>no in common properties Skipping build of: ./headers <build>no in common properties Skipping build of: ./headers <build>no in common properties warning: Graph library does not contain optional GraphML reader. note: to enable GraphML support, set EXPAT_INCLUDE and EXPAT_LIBPATH to the note: directories containing the Expat headers and libraries, respectively. warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. Building Boost.Regex with the optional Unicode/ICU support disabled. Note: Please refer to the Boost.Regex documentation for more information Note: this is a strictly optional feature. Skipping build of: ./build_all <build>no in common properties Skipping build of: ./build_all <build>no in common properties Skipping build of: ./build_all <build>no in common properties Skipping build of: ./build_all <build>no in common properties common.mkdir bin.v2 if not exist "bin.v2\\" mkdir "bin.v2" 'C:\Documents' is not recognized as an internal or external command, operable program or batch file. ...skipped bin.v2\libs for lack of bin.v2... Thanks in advance.

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Re: [Boost-users] Installing boost 1.38 in UBUNTU 8.10 (Alain Leblanc)
by jan acosta 03 Mar '09

03 Mar '09

Did you verify that you have a file named boost_python-gcc41-mt.so or boost_python-gcc41-mt.a? Depending on the options you used when you installed boost they may have a different name, such as without the gcc42 or with an extra -1.38. Yes I verified that those are the names. My compiler version is gcc41. I had to downgrade from gcc42 to gcc41 because Cuda has problems running at higher versions of the compiler. To install hedge or pycuda, I only have to put boost_python-gcc41-mt in this file he wants us to make: The following text should be placed in $HOME/.aksetup-defaults.py: BOOST_INC_DIR = ['/users/sfield/pool/include/boost-1_38/'] BOOST_LIB_DIR = ['/users/sfield/pool/lib'] BOOST_BINDINGS_INC_DIR = ['/users/sfield/pool/include/boost-numeric-bindings/'] BOOST_PYTHON_LIBNAME = ['boost_python-gcc41-mt'] BOOST_MPI_LIBNAME = ['boost_mpi-gcc41-mt'] # WITH_SPARSE_WRAPPERS = True Should I try to change the name to boost_python-gcc41-mt.so or boost_python-gcc41.a? I have all of these files in my boost library folder. These are the things I need to get installed: http://webapp.dam.brown.edu/wiki/SciComp/InstallHedgeFromGit http://documen.tician.de/pycuda/ I'm stuck and don't know what else to do....

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Re: [Boost-users] Formal Review: Boost.RangeEx
by Alan M. Carroll 03 Mar '09

03 Mar '09

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RE [Q] any successes in building 1.38+GCC-4.3.2+cygwin
by Vial, Florent 03 Mar '09

03 Mar '09

>>> ./boost/config/requires_threads.hpp:29:4: error: #error "Threading >>> support unavaliable: it has been explicitly disabled with BOOST_DISABLE_THREADS" >> This may be an issue with 4.3.2 as it works fine with 3.4.4. >AFAIR, there is no pthreads in gcc-4 on cygwin. I agree with that. I tried it too for a couple of weeks, but the current gcc 4.3.2 version installed in cygwin was built without pthread. Try a "$gcc-4.exe --v". On my machine it returns: Using built-in specs. Target: i686-pc-cygwin Configured with: /gnu/gcc/release/gcc4-4.3.2-1/src/gcc-4.3.2/configure --srcdir=/gnu/gcc/release/gcc4-4.3.2-1/src/gcc-4.3.2 --prefix=/usr --exec-prefix=/us --bindir=/usr/bin --sbindir=/usr/sbin --libexecdir=/usr/sbin --localstatedir=/var --sysconfdir=/etc --datadir=/usr/share --infodir=/usr/share/info --mandi =/usr/share/man -v --with-gmp=/usr --with-mpfr=/usr --enable-bootstrap --enable-version-specific-runtime-libs --with-slibdir=/usr/bin --libexecdir=/usr/lib --enable-static --enable-shared --enable-shared-libgcc --enable-__cxa_atexit --with-gnu-ld --with-gnu-as --with-dwarf2 --disable-sjlj-exceptions --enable-l nguages=ada,c,c++,fortran,java,objc,obj-c++ --disable-symvers --enable-libjava --program-suffix=-4 Thread model: single gcc version 4.3.2 20080827 (alpha-testing) 1 (GCC) The line saying "Thread model: single" says it all... HTH, Florent Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRA 57918 Personlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRB 54477 Geschaftsfuhrer: Prof. Dr. Dejan Ilic; Franz Kraus; Jens Schafer

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problems with 32-bit Boost libs on Linux 64-bit with multilib gcc
by Damien Hocking 03 Mar '09

03 Mar '09

Hi all, I'm having some problems with building a 32-bit Boost on a 64-bit Linux. I'm building 1.38 and I need 64 and 32-bit version of the libraries. The compiler is gcc 4.3.2 with the multilibs installed (Ubuntu 8.10). My builds go through successfully, but when I link my 32-bit version of my application to what should be 32-bit Boost libraries, I get the "skipping incompatible" warning from the linker, which means that the address model is wrong. For example: /usr/bin/ld: skipping incompatible 3rdparty/boost/linux/x86/debug/libboost_serialization-gcc43-mt-d-1_38.so The 64-bit libraries are fine and the application links and runs correctly. I noticed in gcc.jam there's a comment about not being able to build a clean 32-bit binary with a 64-bit compiler. This is my bjam command for a 32-bit Boost build: bjam --build-dir=./build32 address-model=32 --build-type=complete --stagedir=./stage32 stage Do I need a -m32 in a config file or something extra on that command line? Damien

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Timing of BoostPro 1.38 Installer?
by Scott Meyers 03 Mar '09

03 Mar '09

Does anybody happen to know when an installer will be available for Boost 1.38? Thanks, Scott

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[Q] any successes in building 1.38+GCC-4.3.2+cygwin
by V S P 03 Mar '09

03 Mar '09

I was trying to test my code on gcc and since do not have access to linux, I used cygwin gcc v 4.3.2 with boost 1.38. I first built bjam (it went Ok). copied it to /bin then created symlink g++ to gcc-4 (cygwin has gcc 4.3.2 as gcc-4) and then with this command bjam toolset=gcc variant=debug release link=shared threading=multi runtime-link=shared stage started the build thread library built (although I am not sure if pthreads are supported on cygwin, may be it was just a dummy library). Many link errors. So wanted to ask if anybody has tried - or if you guys would recommend to try the same with gcc-3.4 thank you in advance -- V S P toreason(a)fastmail.fm -- http://www.fastmail.fm - One of many happy users: http://www.fastmail.fm/docs/quotes.html

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Taucs installation
by Chaman Singh Verma 03 Mar '09

03 Mar '09

Hello, I downloaded "Taucs" from the CGAL site, but it seems that installation is not clean. Can someone tell what I must do ? Thanks. csv csv610@blackhole:~/Downloads/taucs_full$ export OSTYPE=linux csv610@blackhole:~/Downloads/taucs_full$ ./configure ./configure: 61: [[: not found cc -o configurator/configurator configurator/taucs_config.c rm -rf lib/linux/* rm -rf obj/linux/* rm -rf bin/linux/* rm -rf lib/linux/*.* rm -rf obj/linux/*.* rm -rf bin/linux/*.* rm -rf build/linux/taucs_config_tests.h rmdir obj/linux/ rmdir: failed to remove `obj/linux/': No such file or directory make: [clean] Error 1 (ignored) rmdir bin/linux/ rmdir: failed to remove `bin/linux/': No such file or directory make: [clean] Error 1 (ignored) rmdir lib/linux/ rmdir: failed to remove `lib/linux/': No such file or directory make: [clean] Error 1 (ignored) csv610@blackhole:~/Downloads/taucs_full$

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Visual C++ 9.0 + WinCE
by Hernan Di Pietro 03 Mar '09

03 Mar '09

I'm using Boost 1.37 and I've found that using the headers to develop WinCE applications with WinCE causes Boost header config/compiler/visualc.hpp to emit the EVC++ version not recognized. I've patched the *visualc.hpp* header to recognize the WinCE/VC9 configuration as follows: (line 150): # if defined(UNDER_CE) # if _MSC_VER < 1200 // Note: these are so far off, they are not really supported # elif _MSC_VER < 1300 // eVC++ 4 comes with 1200-1202 # define BOOST_COMPILER_VERSION evc4.0 # elif _MSC_VER == 1400 # define BOOST_COMPILER_VERSION evc8 *# elif _MSC_VER == 1500 # define BOOST_COMPILER_VERSION evc9* # else # if defined(BOOST_ASSERT_CONFIG) # error "Unknown EVC++ compiler version - please run the configure tests and report the results" # else # pragma message("Unknown EVC++ compiler version - please run the configure tests and report the results") # endif # endif Thanks, I dont if there's any workaround already available. Hernán.

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[Function] Small function optimization
by Robert Jones 03 Mar '09

03 Mar '09

A while back I wrote some code which made heavy use of small boost::functions, using Boost 1.33.1. The performance hit was pretty grim, and in the end I had to take thme out and use non generic hand rolled solutions. However, we have recently upgraded to Boost 1.37, and I notive from all the Boost version issue docs that a small function optimization was added in n Boost 1.35. Can anyone tell me in general terms what was done, and possibly if I'm likely to find the performance significantly better now. Many Thanks, Rob.

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can't debug into BOOST_FOREACH?
by Stephan Menzel 03 Mar '09

03 Mar '09

Hi there, I just noticed there seems to be no way of debugging into a BOOST_FOREACH loop... Is that true? I use g++ 4.3 / gdb 6.8 here and neither would the debugger stop any any breakpoint inside such loops nor can I step into them from outside. Is this supposed to be like that? puzzled... Stephan

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New and updated serialization performance results
by Brian Wood 03 Mar '09

03 Mar '09

Recently I updated this comparsion, http://webEbenezer.net/comparison.html, of Ebenezer Enterprises and the Boost Serialization library. Here's a link to the previous version of that file, http://webEbenezer.net/compprev.html. The previous tests used Boost 1.34.1 and the updated versions use Boost 1.38. I didn't detect any improvement performance- wise in the Boost Serialization library in this round of testing. In addition to the updated results, I've added some new tests that test loading/receiving data. Although Boost Serialization comes closer to Ebenezer times when loading/receiving data than it does when saving/sending data, there still is a gap between the two. That gap is greatest when (multi)set, (multi)map, or rb_tree are used. This is probably because Boost Serialization doesn't use the insert with a hint function available with these containers. I believe that multi_index uses the hinted verison of insert in it's marshalling code, so in my opinion it makes sense to consider this in Boost Serialization also. Additionally, we've added support for flex_string, http://erdani.org/code/main.html, to the site. On that page it says Harmut Kaizer reported that dropping flex_string into the Wave Boost Preprocessor improved it's speed by 5-10%, depending on input. I've done a few performance tests comparing the two strings and also found flex_string to be more efficient than std::string. Brian Wood Ebenezer Enterprises www.webEbenezer.net "Then Samuel took a rock and set it up between Mizpah and Shen. He named it Ebenezer [Rock of Help] and said, 'Until now the LORD has helped us.'"

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[result_of] member function
by er 03 Mar '09

03 Mar '09

Hi All, Is this feasible? How? class Foo { template<typename Signature> struct result{}; template<typename F> struct result<(F::*f)(value_type)>{ typedef value0_type if f == foo, value1_type if f == bar type; }; value0_type foo(value_type); value1_type bar(value_type); }; How do I invoke result_of to get the result type of F::foo(value_type)?

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Re: [Boost-users] [asio] still weird crashes with asio using libpion on windows
by FantasyDR 03 Mar '09

03 Mar '09

I met the same issue. And finally I found it was caused by the sequence of object destruction. The asio needs an io_service object to handle all async call. The io_service implementation such as win_iocp_io_service hold a list of its service instance. These instances may be held by object such as tcp::acceptor from their constructor. If io_service was destroyed before the tcp::acceptor then the instance pointer will be released and cause a crash in tcp::acceptor's destructor. The solution is very simple: make sure the io_service was destroyed after all other object that may hold a reference to it. I hope I've described it clearly and can give you some help :-) Bugzilla from stephan.menzel(a)gmx.eu wrote: > > Hi all, > > I have been experiencing problems with weird crashes on Windows using > libpion (http://www.pion.org/projects/pion-network-library) and the > problem is still there with pion 1.0.10 but it changed a little and might > shed some new light on the > Let me just outline the situation. I have a simple project with an app and > two libs, both using boost 1.36 at this time. The app links against those > two libs, and one of the libs links against pion. So does the app of > course. I've built pion as debug dll with boost 1.36. This runs on Windows > and Linux. > Now on Linux everything is fine, no problem at all, no dangerous valgrind > output, nothing. > On Windows however, the application crashes as soon as I do something with > pion, and the callstack leads me to believe it's got something to do with > boost asio. > > Usually it happens within asio win_mutex and looks a lot like this: > http://trac.atomiclabs.com/ticket/32 > To me this looks like an uninitialized mutex is being used. > Not entirely however. I get this: > > First-chance exception at 0x7c91100b in myapp.exe: 0xC0000005: Access > violation reading location 0x00000028. > > it's in win_mutex.hpp > > int do_lock() > { > #if defined(__MINGW32__) > // Not sure if MinGW supports structured exception handling, so for > now > // we'll just call the Windows API and hope. > ::EnterCriticalSection(&crit_section_); > return 0; > #else > __try > { > -> ::EnterCriticalSection(&crit_section_); // CRASH > } > __except(GetExceptionCode() == STATUS_INVALID_HANDLE > || GetExceptionCode() == STATUS_NO_MEMORY > ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH) > { > if (GetExceptionCode() == STATUS_NO_MEMORY) > return ERROR_OUTOFMEMORY; > return ERROR_INVALID_HANDLE; > } > > return 0; > #endif > } > > This exception repeats many times until eventually the app crashes because > 'this' is invalid, pointing somewhere it shouldn't. > The Bug occurs several seconds after the application has started, but I > don't have to actually access pion's http socket for that. I think it > might not be pion's fault at all. > > The whole thing only happens on Windows and renders both pion useless on > that system. I know, it's only Windows but I've been debugging around that > for some months now and I'd really like that solved at some point. > > Any ideas? > > Thanks a lot... > > Stephan > > > PS: > I can't go to boost 1.37 because of: > https://svn.boost.org/trac/boost/ticket/2541 > With Chris apparently not responding or posting about ASIO any more is > there any chance of this being fixed in the next release? Is ASIO > maintained at all? Cause nobody seems to care about that bug. Again, I > know it's only Windows but as long as Windows is officially a supported > system an imporant lib like ASIO should work on it. > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > -- View this message in context: http://www.nabble.com/-asio--still-weird-crashes-with-asio-using-libpion-on… Sent from the Boost - Users mailing list archive at Nabble.com.

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Formal Review: Boost.RangeEx
by Thorsten Ottosen 02 Mar '09

02 Mar '09

Dear Developers and Users, It's my pleasure to announce that the review of Neil Groves' RangeEx library starts today and lasts until March 3, 2009. What is it? +++++++++++ The library provide two very useful extensions to the range library 1. Range-based algorithms. E.g. boost::sort( rng ); which is a convenient wrapper of instead of std::sort( boost::begin(rng), boost::end(rng) ); But the new interface also allows for more expressive code because (on the fly) composition of algorithms suddenly is possible. 2. Range adaptors. E.g. std::vector<int> vec = ...; boost::copy( vec | boost::adaptors::reversed, std::ostream_iterator<int>( std::cout ) ); where the expression "vec | boost::adaptors::reversed" wraps the iterators of the range on the left in reverse iterators. The library provides a wide range (no pun intended) of Range adaptors, and they are a powerful way to create ranges on the fly and pass them to algorithms. Getting the library +++++++++++++++++++ The library may be downloaded from http://www.cs.aau.dk/~nesotto/boost/range_ex.zip or from the Boost vault under "Algorithms". The docs may be browsed online here http://www.cs.aau.dk/~nesotto/boost/libs/range/ Please note that the documentation is integrated with the current Range ilbrary. Therefore the relevant sections for the review is http://www.cs.aau.dk/~nesotto/boost/libs/range/doc/adaptors.html and http://www.cs.aau.dk/~nesotto/boost/libs/range/doc/algorithms.html The code may be browsed here: http://www.cs.aau.dk/~nesotto/boost/boost/range/ Notice the library is header only (exception: the adaptor tokenized() depends on Boost.Regex). Writing a review ++++++++++++++++ If you feel this is an interesting library, then please submit your review to the developer list (preferably), or to the review manager. Here are some questions you might want to answer in your review: - 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? And finally, every review should answer this question: - Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Special considerations ++++++++++++++++++++++ Various RangeEx like libraries have been implemented in the past. You might want to compare with those libraries when you form your oppinion: 1. John Torjo's range lib http://rangelib.synesis.com.au/libs/boost-rangelib-20040913.zip http://torjo.com/rangelib/index.html 2. Adobe's ASL libraries include range-based algorithms: http://stlab.adobe.com/group__algorithm.html I'm looking forward to your review. best regards Thorsten, Review Manager

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[Review] Reminder: Boost.RangeEx review is going on
by Thorsten Ottosen 02 Mar '09

02 Mar '09

Dear Developers and Users, The review of Neil Groves' RangeEx library lasts until March 3, 2009. Please find the time to do a review if you are interested in this library. The discussion so far may be found here: http://archives.free.net.ph/message/20090220.122836.73bdbd04.en.html Below you will find a description of the library and information on how to write a review. best regards Thorsten, review manager What is it? +++++++++++ The library provide two very useful extensions to the range library 1. Range-based algorithms. E.g. boost::sort( rng ); which is a convenient wrapper of instead of std::sort( boost::begin(rng), boost::end(rng) ); But the new interface also allows for more expressive code because (on the fly) composition of algorithms suddenly is possible. 2. Range adaptors. E.g. std::vector<int> vec = ...; boost::copy( vec | boost::adaptors::reversed, std::ostream_iterator<int>( std::cout ) ); where the expression "vec | boost::adaptors::reversed" wraps the iterators of the range on the left in reverse iterators. The library provides a wide range (no pun intended) of Range adaptors, and they are a powerful way to create ranges on the fly and pass them to algorithms. Getting the library +++++++++++++++++++ The library may be downloaded from http://www.cs.aau.dk/~nesotto/boost/range_ex.zip or from the Boost vault under "Algorithms". The docs may be browsed online here http://www.cs.aau.dk/~nesotto/boost/libs/range/ Please note that the documentation is integrated with the current Range ilbrary. Therefore the relevant sections for the review is http://www.cs.aau.dk/~nesotto/boost/libs/range/doc/adaptors.html and http://www.cs.aau.dk/~nesotto/boost/libs/range/doc/algorithms.html The code may be browsed here: http://www.cs.aau.dk/~nesotto/boost/boost/range/ Notice the library is header only (exception: the adaptor tokenized() depends on Boost.Regex). Writing a review ++++++++++++++++ If you feel this is an interesting library, then please submit your review to the developer list (preferably), or to the review manager. Here are some questions you might want to answer in your review: - 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? And finally, every review should answer this question: - Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Special considerations ++++++++++++++++++++++ Various RangeEx like libraries have been implemented in the past. You might want to compare with those libraries when you form your oppinion: 1. John Torjo's range lib http://rangelib.synesis.com.au/libs/boost-rangelib-20040913.zip http://torjo.com/rangelib/index.html 2. Adobe's ASL libraries include range-based algorithms: http://stlab.adobe.com/group__algorithm.html I'm looking forward to your review. best regards Thorsten, Review Manager

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IEC/SI Binary Prefix Formatter
by Rodrigo Madera 02 Mar '09

02 Mar '09

Hello guys, I'm wondering if in the Boost universe we already have something to format numbers according to IEC's "new" prefixes (such as MiB and GiB) or SI prefixes (such as MB and GB). What I'm looking for is something like: formatter << boost::iec_prefix << 5*1024*1024; // Will output "5 GiB" formatter << boost::si_prefix << 5*1024*1024; // Will output "5GB" Do you have anything like this? Thank you for your support, Rodrigo Madera

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[asio] SSL enabled http server3 example is blocking
by Jean-Pierre Bergamin 02 Mar '09

02 Mar '09

Dear boost-users I changed the http server3 example (many thready run io_service::run()) to use SSL connections. I now face the problem that the async_accept handler is only called when no other connections are alive and not immediately by another thread as with the original non-ssl example. My modified request_handler simply sleeps for 10 seconds. Now when a request arrives while another one is being processed (sleeping), it is only handled after the other one finished. By setting a breakpoint in server::handle_accept() I can see that this handler for the second request is only called after the first connection has been destroyed/closed. This happens on Windows XP. Do you may have an idea why the accept handler is not called immediately or where the blocking could happen? I may help if you could test this on another platform then XP. To test this, apply the attached patch to the directory boost_1_38_0/libs/asio/example/http/server3 and copy the *.pem files from the asio ssl example to the working directory of the server3 example. Regards James PS: I already posted this question to the asio-users list without gettinga reply. I'm trying my luck now here on the boost list. diff -ru server3.orig/connection.cpp server3/connection.cpp --- server3.orig/connection.cpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/connection.cpp 2009-02-17 15:52:12.867198900 +0100 @@ -17,20 +17,20 @@ namespace server3 { connection::connection(boost::asio::io_service& io_service, + boost::asio::ssl::context &context, request_handler& handler) : strand_(io_service), - socket_(io_service), + socket_(io_service, context), request_handler_(handler) { } -boost::asio::ip::tcp::socket& connection::socket() +connection::socket_type::lowest_layer_type& connection::socket() { - return socket_; + return socket_.lowest_layer(); } -void connection::start() -{ +void connection::handle_handshake(const boost::system::error_code& e) { socket_.async_read_some(boost::asio::buffer(buffer_), strand_.wrap( boost::bind(&connection::handle_read, shared_from_this(), @@ -38,6 +38,14 @@ boost::asio::placeholders::bytes_transferred))); } +void connection::start() +{ + socket_.async_handshake(boost::asio::ssl::stream_base::server, + boost::bind(&connection::handle_handshake, shared_from_this(), + boost::asio::placeholders::error) + ); +} + void connection::handle_read(const boost::system::error_code& e, std::size_t bytes_transferred) { @@ -85,7 +93,7 @@ { // Initiate graceful connection closure. boost::system::error_code ignored_ec; - socket_.shutdown(boost::asio::ip::tcp::socket::shutdown_both, ignored_ec); + socket_.shutdown(ignored_ec); } // No new asynchronous operations are started. This means that all shared_ptr diff -ru server3.orig/connection.hpp server3/connection.hpp --- server3.orig/connection.hpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/connection.hpp 2009-02-26 08:51:42.187500000 +0100 @@ -12,6 +12,7 @@ #define HTTP_SERVER3_CONNECTION_HPP #include <boost/asio.hpp> +#include <boost/asio/ssl.hpp> #include <boost/array.hpp> #include <boost/noncopyable.hpp> #include <boost/shared_ptr.hpp> @@ -30,17 +31,20 @@ private boost::noncopyable { public: + typedef boost::asio::ssl::stream<boost::asio::ip::tcp::socket> socket_type; /// Construct a connection with the given io_service. explicit connection(boost::asio::io_service& io_service, + boost::asio::ssl::context &context, request_handler& handler); /// Get the socket associated with the connection. - boost::asio::ip::tcp::socket& socket(); + socket_type::lowest_layer_type& socket(); /// Start the first asynchronous operation for the connection. void start(); - + ~connection() {} private: + void handle_handshake(const boost::system::error_code& e); /// Handle completion of a read operation. void handle_read(const boost::system::error_code& e, std::size_t bytes_transferred); @@ -52,7 +56,7 @@ boost::asio::io_service::strand strand_; /// Socket for the connection. - boost::asio::ip::tcp::socket socket_; + socket_type socket_; /// The handler used to process the incoming request. request_handler& request_handler_; diff -ru server3.orig/reply.cpp server3/reply.cpp --- server3.orig/reply.cpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/reply.cpp 2009-02-17 15:52:20.804800500 +0100 @@ -119,7 +119,7 @@ namespace stock_replies { -const char ok[] = ""; +const char ok[] = "ok\r\n"; const char created[] = "<html>" "<head><title>Created</title></head>" diff -ru server3.orig/request_handler.cpp server3/request_handler.cpp --- server3.orig/request_handler.cpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/request_handler.cpp 2009-02-26 08:23:56.250000000 +0100 @@ -8,6 +8,7 @@ // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // +#include <boost/thread.hpp> #include "request_handler.hpp" #include <fstream> #include <sstream> @@ -27,56 +28,9 @@ void request_handler::handle_request(const request& req, reply& rep) { - // Decode url to path. - std::string request_path; - if (!url_decode(req.uri, request_path)) - { - rep = reply::stock_reply(reply::bad_request); - return; - } - - // Request path must be absolute and not contain "..". - if (request_path.empty() || request_path[0] != '/' - || request_path.find("..") != std::string::npos) - { - rep = reply::stock_reply(reply::bad_request); - return; - } - - // If path ends in slash (i.e. is a directory) then add "index.html". - if (request_path[request_path.size() - 1] == '/') - { - request_path += "index.html"; - } - - // Determine the file extension. - std::size_t last_slash_pos = request_path.find_last_of("/"); - std::size_t last_dot_pos = request_path.find_last_of("."); - std::string extension; - if (last_dot_pos != std::string::npos && last_dot_pos > last_slash_pos) - { - extension = request_path.substr(last_dot_pos + 1); - } - - // Open the file to send back. - std::string full_path = doc_root_ + request_path; - std::ifstream is(full_path.c_str(), std::ios::in | std::ios::binary); - if (!is) - { - rep = reply::stock_reply(reply::not_found); - return; - } - - // Fill out the reply to be sent to the client. - rep.status = reply::ok; - char buf[512]; - while (is.read(buf, sizeof(buf)).gcount() > 0) - rep.content.append(buf, is.gcount()); - rep.headers.resize(2); - rep.headers[0].name = "Content-Length"; - rep.headers[0].value = boost::lexical_cast<std::string>(rep.content.size()); - rep.headers[1].name = "Content-Type"; - rep.headers[1].value = mime_types::extension_to_type(extension); + using namespace boost; + this_thread::sleep(posix_time::seconds(10)); + rep = reply::stock_reply(reply::ok); } bool request_handler::url_decode(const std::string& in, std::string& out) diff -ru server3.orig/server.cpp server3/server.cpp --- server3.orig/server.cpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/server.cpp 2009-02-17 16:24:16.173066900 +0100 @@ -21,9 +21,23 @@ const std::string& doc_root, std::size_t thread_pool_size) : thread_pool_size_(thread_pool_size), acceptor_(io_service_), - new_connection_(new connection(io_service_, request_handler_)), + context_(io_service_, boost::asio::ssl::context::sslv23), + new_connection_(new connection(io_service_, context_, request_handler_)), request_handler_(doc_root) { + + context_.set_options( + boost::asio::ssl::context::default_workarounds + | boost::asio::ssl::context::no_sslv2 + | boost::asio::ssl::context::single_dh_use); + context_.set_password_callback(boost::bind<const char*>(&server::get_password, this)); + + context_.use_certificate_chain_file("server.pem"); + context_.use_private_key_file("server.pem", boost::asio::ssl::context::pem); + context_.use_tmp_dh_file("dh512.pem"); + context_.set_verify_mode(boost::asio::ssl::context::verify_none); + + // Open the acceptor with the option to reuse the address (i.e. SO_REUSEADDR). boost::asio::ip::tcp::resolver resolver(io_service_); boost::asio::ip::tcp::resolver::query query(address, port); @@ -63,7 +77,7 @@ if (!e) { new_connection_->start(); - new_connection_.reset(new connection(io_service_, request_handler_)); + new_connection_.reset(new connection(io_service_, context_, request_handler_)); acceptor_.async_accept(new_connection_->socket(), boost::bind(&server::handle_accept, this, boost::asio::placeholders::error)); diff -ru server3.orig/server.hpp server3/server.hpp --- server3.orig/server.hpp 2008-03-12 10:12:08.000000000 +0100 +++ server3/server.hpp 2009-02-17 16:02:27.187562100 +0100 @@ -39,6 +39,10 @@ void stop(); private: + const char * get_password() const { + return "test"; + } + /// Handle completion of an asynchronous accept operation. void handle_accept(const boost::system::error_code& e); @@ -51,6 +55,8 @@ /// Acceptor used to listen for incoming connections. boost::asio::ip::tcp::acceptor acceptor_; + boost::asio::ssl::context context_; + /// The next connection to be accepted. connection_ptr new_connection_;

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[serialization] Archive reload
by Ferllings 02 Mar '09

02 Mar '09

Hello, I have a Class A with string attributes that I serialize in XML format: Class A { public: string _nom; string _prenom; template<class Archive> void serialize(Archive& ar, const unsigned in version){ ar & boost::serialization::make_nvp("Nom", _nom); ar & boost::serialization::make_nvp("Prenom", _prenom); } } The object is correctly saved using this code: A _a; void save() const { ... oTextArchive::xml_oarchive oTextArchive(ofile); oTextArchive << make_nvp("A", _a); ... } But I want to reload the object, the A attributes aren't updated and keep the previous values: void load() { ... iTextArchive::xml_oarchive iTextArchive(ifile); iTextArchive >> make_nvp("A", _a); ... } The only way I found to reload my object is to use an temporary object: void load() { ... A _tmp; iTextArchive::xml_oarchive iTextArchive(ifile); iTextArchive >> make_nvp("A", _tmp); _a = _tmp; ... } Why can't I update the object directly? Thanks for your help.

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[accumulators] Any was to reset an accumulator_set object?
by dhruva 02 Mar '09

02 Mar '09

Hello, I am using boost::accumulator_set to compute mean. After every 100 samples, I need to start afresh. Since I am using accumulator_set as a member variable in a class (I get samples one at a time and need to preserve accumulator_set object across function calls), I need some mechanism to reset it to its initial state. I am not doing anything fancy like using droppable functionality. As a real crude work around, I am keeping 2 objects. The first is not used for any computing and hence its state is same throughout. The computing is done using the second object. After 100 samples, I just copy the first onto the second hoping the state of second object will be same as first which is the initial state. Is there a better way to achieve the above requirement? -dhruva Download prohibited? No problem. CHAT from any browser, without download. Go to http://in.webmessenger.yahoo.com/

3 2

[lexical_cast] Locales.
by Emre Turkay 02 Mar '09

02 Mar '09

Hi folks, I wonder if there is a downside of adding an optional std::locale argument to lexical_cast? Thanks, Emre Turkay

2 1