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Boost.DLL formal review is ongoing
by Vladimir Prus 15 Jul '15

15 Jul '15

The formal review of Boost.DLL library by Antony Polukhin is nearing the end of the first week. As of today, over 100 people read through the library's tutorial, suggesting quite some interest. However, no reviews were submitted yet. Please take the time to post your thoughts - even if you don't have time to do a full review, or try the library, comments on design and interfaces are still very valuable. The summary of the library features and review checklists are reproduced below. Boost.DLL is a C++98 library for comfortable work with DLL and DSO. Library provides a portable across platforms way to: - load libraries at runtime - import and export any native functions and variables - make alias names for C++ mangled functions and symbols - query libraries/objects and executables for sections and exported symbols - self loading and self querying - getting program and module location by exported symbol The documentation can be found at: http://apolukhin.github.io/Boost.DLL/index.html and the source can be obtained at: https://github.com/apolukhin/Boost.DLL Please post your reviews on the mailing list and if possible, answer the following questions: - Should the library be accepted? - How useful is it? - What's your evaluation of - Design - Implementation - Documentations - Tests - How much effort did you put into your evaluation? - Did you attempt to use the library? On what systems and compilers? Thanks, Volodya _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost

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the stability of breadth_first_visit in BGL
by breadbread1984 15 Jul '15

15 Jul '15

I am wondering if breadth_first_visit can always get the same sequence of vertex no matter whether the graph is serialized and deserialized again. Thx

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Subgraph at distance n
by Rossano Schifanella 15 Jul '15

15 Jul '15

Hi all, which is the easiest way to extract from a graph G and a generic node source a subgraph with all the vertices/edges at distance at most n from source? Thanks a lot for your help. Best, Rossano

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Boost.DLL Review is finished
by Vladimir Prus 15 Jul '15

15 Jul '15

Boosters, the formal review of the Boost.DLL library by Antony Polukhin is now finished. The preliminary results are as follows: The following people have provided reviews: - Ralf Globisch - Yes - Klaim - Joël Lamotte - Yes (*) - Niall Douglas - Yes, conditionally - John P Fletcher - Yes - Bjorn Reese - Yes - Edward Diener - Yes Klaim - Joël has asked that his vote is not counted until he's done trying the library for real, and there was no confirmation it's done yet. The following people have contributed, but did not provide a review - Rodrigo Madera - Thomas Trummer - Rob Stewart - Ion Gaztañaga If anybody would like to amend or clarify anything, or plans to provide additional comments during this week, please contact me off-list. I will post final review result after that. Thanks, Volodya

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Platform checks fail on Centos 6 after bootstrap ?
by gabriel nützi 12 Jul '15

12 Jul '15

Hello all :-) Is somebody able to help with the following problem: http://stackoverflow.com/questions/31347026/boost-build-on-centos-6-5-faile… <http://stackoverflow.com/questions/31347026/boost-build-on-centos-6-5-faile…> boost 1.58 used I dont know why platform checks are not done correctly? Thanks a lot!

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[Boost-announce] [boost] [review] Metaparse Review Result
by Christophe Henry 12 Jul '15

12 Jul '15

Hi all, First of all, the final result. Metaparse is formally unconditionally accepted into Boost. We had 11 reviews, all "Yes" votes. 2 "No" reviews based on formality were later reversed to a "Yes". The review was lively, with a general agreement that the library is very useful, the design of high quality and the documentation great. Here are some noticeable quotes which helped me take my decision: - "thank you Abel for submitting such an amazing library. The quality of the documentation and code is wonderful and it has been a pleasure to review Metaparse." (Michael Caisse) - (Design) "Of high quality. Based on the MPL paradigm, but I don't view this as a problem." (Peter Dimov) - "Part of the role of boost is to push compilers to the limit (and sometimes beyond). This library certainly has the capabilities to do so." (Roland Bock) Worth noticing is the review of Gordon Woodhull. I myself wrote a new front-end for MSM using Metaparse, and other use cases were very welcome and Gordon managed to produce one for his compile-time graph library by the end of the review, which I found impressive (for both the reviewer and the library). Thank you for investing time in this review. Another important factor for me for acceptance is how well the author is going to maintain his library. We have too many abandoned libraries. Abel went out of his way to oblige remarks and demands made by reviewers. Long before the reviews he also had obliged my many critics and demands. He also showed himself open for experiments. All this while keeping a very calm and professional tone. This is for me a very good sign of a library which will be well-maintained. Finally, there were some repeated important comments which I see as adressed to the rest of Boost that the library is targeted towards library writers. >From Peter Dimov: > - Are you knowledgeable about the problem domain? "I'm not sure if anybody is. :-)" It all depends on us, library and potential library writers to become knowledgeable about this domain and make this library move from potentially useful to very useful. We need to use it to write more cool libraries. I notice a recurring theme where Boost would be dead or on the way to doom etc etc. Some very popular Boost libraries are now part of the Standard, and so what? We need to make new ones. Metaparse is one of them. Let's build more, using it! Yes Reviews(11): Andrzej Krzemienski Bjorn Reese Gordon Woodhull Lee Clagett Louis Dionne Michael Caisse Paul A. Bristow Peter Dimov Roland Bock Edward Diener Niall Douglas I want to thank all the reviewers who invested their time in this review and those who provided some usefuls comments. I also want to thank Abel for presenting this great library. Christophe Henry Metaparse Review Manager

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Slow decoding in thread
by Gonzalo Garramuno 11 Jul '15

11 Jul '15

I am writing a movie player using boost. I use a condition_variable to control a mutex in one thread that waits for packets of video to be ready for decoding, while another thread feeds those packets. My problem is that the decode thread may end up doing a lot of work when playing backwards and it is not ready to wait on the condition variable when the message comes from the other thread and so it hangs (or so I think). This is my wait loop. I apologize for the use of macros. #define SCOPED_LOCK(mutex) Mutex::scoped_lock lk_##mutex(mutex) #define CONDITION_WAIT( cond, mutex ) cond.wait( lk_##mutex ); void aviImage::wait_image() { mrv::PacketQueue::Mutex& vpm = _video_packets.mutex(); SCOPED_LOCK( vpm ); for(;;) { if ( stopped() || ! _video_packets.empty() ) break; CONDITION_WAIT( _video_packets.cond(), vpm ); } return; } When it returns it tries to decode one or more frames of video taken from _video_packets. The condition variable is notified whenever the program calls push_back() to add a packet. That is: class PacketQueue { .... inline void push_back( AVPacket& pkt ) { Mutex::scoped_lock lk( _mutex ); // assert( pkt.dts != MRV_NOPTS_VALUE ); if ( av_dup_packet(&pkt) < 0 ) { std::cerr << "Could not duplicate packet - not added" << std::endl; return; } _packets.push_back( pkt ); _bytes += pkt.size; _cond.notify_one(); } }; Can somebody suggest an alternative to this scheme? -- Gonzalo Garramuño

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Query: metis_input_exception
by Mayank Bakshi 10 Jul '15

10 Jul '15

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crc updating how?
by U.Mutlu 10 Jul '15

10 Jul '15

Hi, I need to calc the crc chunkwise (ie. calc crc of a block, then continue with the next block etc.). Is this (not) possible with the boost crc? In other words: how can the type "crc_32_type" be initialized with a user supplied uint32_t value? boost::crc_32_type crc; crc = 0x1234; // <-- this brings compile error crc.process_bytes(buf, len); error: no match for ‘operator=’ (operand types are ‘boost::crc_32_type {aka boost::crc_optimal<32ul, 79764919u, 4294967295u, 4294967295u, true, true>}’ and ‘const uint32_t {aka const unsigned int}’) Thx

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[crc] bug in boost::crc
by U.Mutlu 10 Jul '15

10 Jul '15

/* boost-crc-bug-demo.cpp Written by U.Mutlu on 2015-07-09-Th Compile: g++ -O2 -Wall -std=gnu++11 boost-crc-bug-demo.cpp Run: ./a.out Output: crc("The quick brown fox jumps over the lazy dog")=414fa339 crc("The quick brown fox ")=88b075e2 crc("The quick brown fox jumps over the lazy dog")=4ac56d0f ERROR See also: http://www.boost.org/doc/libs/1_58_0/libs/crc/crc.html#usage Conclusion: It doesn't do what it should and also advertises; ie. there's a bug */ #include <boost/crc.hpp> #include <boost/cstdint.hpp> #include <iostream> int main() { uint32_t expected; { const std::string sTxt = "The quick brown fox jumps over the lazy dog"; boost::crc_optimal<32, 0x04C11DB7, 0xFFFFFFFF, 0xFFFFFFFF, true, true> crc; crc.process_bytes(sTxt.data(), sTxt.size()); std::cout << "crc(\"" << sTxt << "\")=" << std::hex << crc.checksum() << std::endl; // save the result for the following test expected = crc.checksum(); } // test: doing the same as above, but now in 2 steps, ie. chunk- or blockwise: std::string sTxt; uint32_t result = 0xFFFFFFFF; for (size_t i = 0; i <= 1; ++i) { sTxt += !i ? "The quick brown fox " : "jumps over the lazy dog"; // using the special ctor for initial remainder stored in "result" boost::crc_optimal<32, 0x04C11DB7, 0xFFFFFFFF, 0xFFFFFFFF, true, true> crc(result); crc.process_bytes(sTxt.data(), sTxt.size()); std::cout << "crc(\"" << sTxt << "\")=" << std::hex << crc.checksum() << std::endl; result = crc.checksum(); } // eval: const std::string sRes = result == expected ? "SUCCESS" : "ERROR"; std::cout << sRes << std::endl; return 0; }

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