- Boost - lists.preview.boost.org

[container][stable_vector] What does reserve() do for stable_vector
by Arindam Mukherjee 19 Apr '15

19 Apr '15

Consider the following code. #include <string> #include <boost/container/stable_vector.hpp> #include <iostream> int main() { boost::container::stable_vector<std::string> vec; vec.reserve(10); std::cout << "capacity = " << vec.capacity() << '\n'; } On running this (on g++ and Linux), the output is: capacity = 4294967286 (that's 2^32 - 10) If replace boost::container::stable_vector with std::vector above, the output is: capacity = 10 I know it could as well have been capacity = 20, or capacity = 64 or whatever but that's still sane behavior. What capacity() returns for stable_vector seems to be (2^32 - N), N being the requested capacity. I didn't see such a definition of capacity in the docs: http://www.boost.org/doc/libs/1_56_0/doc/html/boost/container/stable_vector… Thanks, Arindam

2 1

[type_traits] Testing for copy constructor
by Edward Diener 19 Apr '15

19 Apr '15

Does one use has_trivial_copy or has_nothrow_copy to determine if a class has a copy constructor or not ? I am writing some code that can do different things depending on whether a particular class has a copy constructor or does not have a copy constructor. I do not really care whether the copy constructor is a compiler generated copy constructor or not.

2 1

Feedback on Boost.Http
by Vinícius dos Santos Oliveira 18 Apr '15

18 Apr '15

I recently submitted an HTTP server library to Boost Incubator and I'd appreciate feedback: http://rrsd.com/blincubator.com/bi_library/http/?gform_post_id=1460 I intend to submit to Boost later. This is the library that I developed during GSoC 2014 and I made several improvements (new features, bug fixes, better and extended documentation...) after the end of GSoC. There are a few improvements that I still want to do, but none of them would be a barrier for Boost integration, in my opinion. This library doesn't have a builtin request router, opposed to several libraries out there, then you can use whatever routing style you wish (tree-based, middleware-based, no router...). Also, it follows Boost active style, then you can build your own scheduler around it (prioritize requests from certain IPs, defer acceptance of new connections during server high load, reuse prior constructed objects...). The library follows Asio threading model, then you also choose whether you will handle all requests from the same thread (useful for embedded devices) or multiples ones. The library is fully async, then one thread is not a problem. It has a powerful and flexible file server API, supporting range-based requests, conditional requests, support for ETags and so on. After the GSoC, I had the chance to add tests for asynchronous abstractions and now the implementation is much more trustable and stable. The choice to reuse an existing HTTP parser (the Node.js's C parser) also helps a lot. The simple message-based API helps to support HTTP pipelining, allocation fine tuning and much more. Besides HTTP pipelining, HTTP chunking (and other modern features like 100-continue and HTTP Upgrade) are also supported. There are zero reviews/comments on Boost Incubator right now and I'd love to see more eyes on this lib that does better on many fronts than previous choices. Benchmark is one item that I still need to tackle, btw. But I hope to see good results here too. -- Vinícius dos Santos Oliveira https://about.me/vinipsmaker

1 0

[tools] How to use 1.58.0/bjam --toolset=sun for specified stdlib feature?
by Sergey Sprogis 18 Apr '15

18 Apr '15

Running boost regression unit tests I found it convenient to direct output from every single tested library into a separate logfile. To do that, my testing script (bash) at first extracts the list of all <library>/test lines from status/Jamfile.v2, and puts them into another test_suites.txt file. Then it runs all extracted test suites like this: my_res_dir= `pwd` for dir in `cat test_suites.txt`; do dir1=`echo $dir | sed "s/\//\./g"` cd $BOOST_ROOT/libs/$dir bjam --toolset=sun variant=release > $my_res_dir/$dir1.log 2>&1 done All that worked fine until boost-1.58 in which tools/build/src/tools/sun.jam file was modified so that instead of single standard library it now allows the possibility of using any of 5 available libraries. The question is, how exactly should I define bjam's options in my bash script shown above, if for example, I want to use gnu library in c++03 mode? The proper code inside sun.jam file looks like this: feature.extend stdlib : gnu ; feature.compose <stdlib>gnu : <cxxflags>-std=c++03 <linkflags>-std=c++03 ; but how should I tell to bjam to use this specific library? Thanks, Sergey

3 2

[build] [boost 1.58] Error when compiling with MSVC-7.1
by Ion Gaztañaga 18 Apr '15

18 Apr '15

Hi, I just tried the newly released version with this toolset (I don't think many will use and support it, but still useful). Output when building move from boost/libs/move/test: ..\..\..\b2.exe toolset=msvc-7.1 variant=debug C:/Data/Libs/boost/tools/build/src/tools\msvc.jam:1075: in configure-really *** argument error * rule generate-setup-cmd ( version : command : parent : options * : cpu : global-setup : default-global-setup-options : default-setup ) * called with: ( 7.1 : C:\Program Files (x86)\Microsoft Visual Studio .NET 2003\Vc7\bin : C:\Program Files (x86)\Microsoft Visual Studio .NET 2003\Vc7 : <command>C:\Program Files (x86)\Microsoft Visual Studio .NET 2003\Vc7\bin\cl.exe : i386 : : x86 : vcvars32.bat ) * missing argument global-setup C:/Data/Libs/boost/tools/build/src/tools\msvc.jam:809:see definition of rule 'generate-setup-cmd' being called C:/Data/Libs/boost/tools/build/src/tools\msvc.jam:201: in configure C:/Data/Libs/boost/tools/build/src/tools\msvc.jam:153: in msvc.init C:/Data/Libs/boost/tools/build/src/build\toolset.jam:43: in toolset.using C:/Data/Libs/boost/tools/build/src\build-system.jam:461: in process-explicit-toolset-requests C:/Data/Libs/boost/tools/build/src\build-system.jam:527: in load C:\Data\Libs\boost\tools\build\src/kernel\modules.jam:289: in import C:\Data\Libs\boost\tools\build\src/kernel/bootstrap.jam:139: in boost-build C:\Data\Libs\boost\boost-build.jam:17: in module scope I've found a workaround adding this to user-config.jam, in case anyone needs a workaround: using msvc : 7.1 : : <setup>"C:/Program Files (x86)/Microsoft Visual Studio .NET 2003/Vc7/bin/vcvars32.bat" ; Of course that path is in a 64-bit Windows OS, adjust it to your installed path. Best, Ion

1 0

[Hana] Formal review dates
by Louis Dionne 17 Apr '15

17 Apr '15

Dear Boost, As I already announced in a previous message, a formal review is about to be asked for Hana. The current preferred dates would be April 25 - May 8. However, we are concerned that people might be unavailable to do reviews such a short time before C++Now. The goal of this message is to ask potential reviewers whether they would be available during the proposed period. If people seem unfavorable or if there is too little feedback to this message, we will consider pushing back the review to after C++Now. Note that one reason why I'm trying to squeeze the review before C++Now is because it could hugely help with marketing the library if it was accepted. Regards, Louis

3 4

Release Status?
by Olaf van der Spek 17 Apr '15

17 Apr '15

Hi, What's the status of the release? -- Olaf

2 1

Re: [boost] [Boost-users] [IPC Named Mutex]
by Tom Kent 16 Apr '15

16 Apr '15

On Thu, Apr 16, 2015 at 3:01 AM, Lorenzo Trivelli < trivelli.lorenzo(a)konvergence.it> wrote: > Hi to everyone, > I'm experiencing a strange behaviour of named mutex on > a windows 2008 machine. > symptoms: when the system event log is empty, creation > of named mutex fails with a boost::interprocess::interprocess:exception > with msg boost::interprocess_exception::library_error. > Now some data: > 1) Boost 1.57.0 + stlport 5.2 > 2) VS 2005 > 3) Target Environment: Win 2008/32 > 3) after a night of code digging I managed to crete a small sample > which raises the exception: > > #include <boost/shared_ptr.hpp> > #include <boost/interprocess/sync/named_mutex.hpp> > #include <boost/interprocess/sync/scoped_lock.hpp> > #include <iostream> > > typedef boost::shared_ptr<boost::interprocess::named_mutex> > safe_ipc_mx; > > static safe_ipc_mx __mx; > int main(void) { > system("pause"); > try { > __mx = safe_ipc_mx(new > boost::interprocess::named_mutex(boost::interprocess::open_or_create_t(),"JAEGER")); > std::cout << std::endl << "Mutex created !" << std::endl; > } catch(boost::interprocess::interprocess_exception const& e) { > std::cout << std::endl << "Mutex creation error " << > e.what() << " /" << e.get_error_code() << " /" << e.get_native_error(); > } > system("pause"); > return 0; > > } > > I tried it also, and got the same result. I also tried with msvc-12.0, same result. > as far as I digged, it seems that the trouble is in the > winapi::get_last_bootup_time(stamp) call > in shared_dir_helpers.hpp, but up to now I had not been able to reproduce > it on a machine with > all the debugging tools installed > get_last_bootup_time() looks through the system event log for event ID == 6005 (event log started)...since the event log was cleared out, this is not found. I guess that is a bug in boost. One thing you could try...in interprocess's win32_api.hpp, there is another implementation of get_last_bootup_time() which uses WMI instead of the event log (there were warnings in the source about WMI not supporting hibernation/clock changes correctly, so beware). If you define BOOST_INTERPROCESS_BOOTSTAMP_IS_LASTBOOTUPTIME it should use that other version...give that a try. (in visual studio Project Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions: add a semi colon ';' then the above item) That worked for me on windows 7. I submitted a pull request to automatically fallback to WMI if the event log started event isn't in the log. https://github.com/boostorg/interprocess/pull/18 Tom

1 0

[serialization] failing MPI build
by Alain Miniussi 16 Apr '15

16 Apr '15

Hi, Am I the only one with a (global) failing build on MPI ? ../../../boost/archive/detail/interface_oarchive.hpp(63): error: no instance of overloaded function "boost::mpi::detail::content_oarchive::save_override" matches the argument list argument types are: (const boost::archive::tracking_type) object type is: boost::mpi::detail::content_oarchive this->This()->save_override(t); I am going to investigate, but maybe I missed something obvious. Thanks Alain

2 17

std::map<> - like structure for other than std::pair<>?
by David Hagood 16 Apr '15

16 Apr '15

Several times I have run into a use case where I have some object that I would like to access via something like a std::map<>, but which already contains a member that I would like to use as a key. Is there any data structure that "acts like a map", but instead of storing std::pair<key,value> allows me to store an object directly, and specify what member of that object is the key value? I can give a specific use case for this: For those of you not familiar with the SCA, there is an object called CF::Properties. This is a CORBA sequence (think std::vector) of objects of {string name, CORBA::Any value}, used to store metadata. Ideally, I'd like to have an object that I could initialize from that sequence that would allow me to do things like this: inline string &getKey(CF::Property &x) { return x.name; } void foo(CF::Properties &meta) { mapLikeThing<CF::Property,getKey> myMap(meta); double sampleRate; myMap["SampleRate"] >> sampleRate; setHardwareSampleRate(sampleRate); }

7 8