December 2008 - Boost-users - lists.preview.boost.org

[Review] UUID library (mini-)review starts today, November 23rd
by Hartmut Kaiser 10 Dec '08

10 Dec '08

Hi all, The mini-review of Andy Tompkins UUID library starts today, November 23rd 2008, and will end on November 30th. I really hope to see your vote and your participation in the discussions on the Boost mailing lists! The library can be downloaded from the vault here (it's the file uuid_v13.zip in the topmost directory): http://tinyurl.com/6xx28b The initial review of the UUID library ended with a provisional acceptance (read here: http://article.gmane.org/gmane.comp.lib.boost.user/27774/) This mini review is meant to allow for a final decision after looking at the changed parts of the library. Here is a list of things fixed and changed: - fixed the licensing issues revealed by the initial review - fixed the security vulnerability revealed by the initial review - renamed to uuid, moved all classes, functions, etc. to namespace boost::uuids - implemented sha1 hash function (thus no license problem) - new class basic_uuid_generator to create random-based uuids. The random number generator is no longer hard coded. It can use any random number generator, default is boost::mt19937 - implemented a good seed function for random number generators - all functions are now reentrant, all classes are as thread safe as an int and the library is no longer dependent on Boost.Thread --------------------------------------------------- Please always state in your review, whether you think the library should be accepted as a Boost library! Additionally please consider giving feedback on the following general topics: - 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? Regards Hartmut Review Manager

14 39

Dplicate emails
by Richard Howells 10 Dec '08

10 Dec '08

Since a couple days back I seem to be getting every email twice. It is coincident with me repaving my computer, but it does NOT happen to my individual emails nor to my other mailing list subscriptions. Is it just me? Cheers, Richard richard(a)dynamisys.co.uk www.dynamisys.co.uk L: (+44) (0)1793 731225 M: (+44) (0)7732 971786

2 1

[boost.build] multiple definitions of symbols at link since revision 49800.
by Nigel Dyer 10 Dec '08

10 Dec '08

Hello I am using the trunk release of boost, and started having problems with multiple definitions of symbols during linking (see example linker output below). I can cure the problem by removing the change to tools\build\v2\build\generators.jam introduced in revision 49800. It only seems to occur if the following headers: #include <boost/test/floating_point_comparison.hpp> #include <boost/lambda/lambda.hpp> #include <boost/lambda/bind.hpp> are included in precompiled headers which are included in cpp files that are created by the antlr parser generator. It occurs on a compilation with darwin, but not msvc. It is unclear whether the generator.jam change has identified a waekness in the boost libraries, or there is a problem with the revision 49800 change that only surfaces in obscure circumstances, or the change has highlighted a problem in my code. It can be fixed by removing the includes from the precompiled header. I feel this should not be necessary As a boost newbie it is unclear whether I should I change my code or raise a bug report. I would be grateful for suggestions. Nigel Example linker failures. /usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: multiple definitions of symbol boost::test_tools::(anonymous namespace)::check_is_close /Volumes/RAID1/xraid/data/bifa/Dev/Projects/Bio/bin/Bio/darwin-4.0.1/release/link-static/libbio.a(BiobaseLexer.o) definition of boost::test_tools::(anonymous namespace)::check_is_close in section (__DATA,__const) /Volumes/RAID1/xraid/data/bifa/Dev/Projects/Bio/bin/Bio/darwin-4.0.1/release/link-static/libbio.a(ArrayLexer.o) definition of boost::test_tools::(anonymous namespace)::check_is_close in section (__DATA,__const)

4 3

[BGL] iterator/descriptor invalidation
by Julius Ziegler 10 Dec '08

10 Dec '08

Dear list, the documentation of adjacency_list states, that a call to add_vertex() does not invalidate any iterators nor descriptors. However, following code segfaults, because retrieving vertex descriptors from an edge_iterator via source() and target() does not work (example should compile as is): #include <iostream> #include <boost/graph/adjacency_list.hpp> using namespace boost; typedef adjacency_list<listS, vecS, directedS > Graph; int main() { Graph g(3); add_edge( 0, 1, g ); add_edge( 1, 2, g ); add_edge( 2, 0, g ); Graph::edge_iterator ei, ei_end; for( tie( ei, ei_end ) = edges( g ); ei != ei_end; ++ei ) { std::cout << source( *ei, g ) << " " << target( *ei, g ) << "\n"; add_vertex( g ); // <- in my real application, vertex gets some // properties that depend on source(...) and // target(...) above } } Is it the case that an edge_iterator does not store vertex_descriptors (that should survive reallocation of the vertex storage), but iterators to the vertex storage? What is the proper way to accomplish something like this? My present workaround is to postpone all add_vertex() calls after the loop, but this costs some storage, and with my graph scaling bigger and bigger, that begins to hurt. Any help and explanation is really appreciated! Regards, Julius

3 18

Re: [Boost-users] [boost] [review][constrained_value] Review of ConstrainedValueLibrary begins today
by jesseperla＠gmail.com 10 Dec '08

10 Dec '08

Robert: >First, I hope that you are aware of the issues with using floating point types >with this library. If not, please read the rationale section of the >documentation and the discussion in the related thread on the developers' list. Yup, been following. You did a good job of educating me on a previous post... I think I understand the issue now, but don't really have much of an option. As far as I can undestand from the discussions, this is a general problem with equality operations with floating points and has nothing to do with your library. If this is true, I would change the "rationale" section to say that the mess is not your fault and it isn'ta library problem and that you need to be just as careful as you would normally. >The constraint could look like this (written out of my head, not tested): If this is possible, I am very happy. It looks like it is. The only other things that I would say need to be thought through in the design is unions of constraints instead of just intersections of them. For example, I was checking this out a while back, and it manages the sets of intervals/etc. well: http://www.herold-faulhaber.de/itl/ I would wonder if formalizing intervals in this library (or using another) is a good way to deal with different bounds... but that is beyond my level of competence. > Why not just use numeric_limits<risk_aversion::value_type>? 1) Because I was too stupid to think of that, and 2) Because I want to be able to write generic functions such as: template<typename T> bool is_NaN(T& t) { return (t == std::numeric_limits< T >::quiet_NaN()); } Again, my idea is that I want to be able to throw around elements of constrained types to generic functions and all of the standard types of things I would do with the superset type. >Actually, only the mutating operators (++, --, =, += etc.) are overloaded. For >I don't think this is needed. If you write: > constrained<int> x, y, z; > z = x + y; >Then simply the + operator for int is used. Even better. As long as it works for all of the auto conversions between intrinsic types we are also in business. eg constrained<int> x, y, z; double c; z = c * x + y; Thanks Robert. Great library, time for me to submit a glowing review.

4 4

socket reconnection
by boost001 10 Dec '08

10 Dec '08

I have an ASIO socket server. I need to close the socket and then listen to the socket again if client disconnected from server. When the server was started, the socket and acceptor are initialized like this: asio_socketPtr = new tcp::socket(asio_service); asio_acceptorPtr = new tcp::acceptor(asio_service, tcp::endpoint(protocol, m_iPort)); in the process closing the socket, I did the following in order: asio_acceptorPtr->close(error_closing); asio_socketPtr->shutdown(tcp::socket::shutdown_both, error_closing); asio_socketPtr->close(error_closing); in the process reopen the socket, I did the following in order: asio_socketPtr->open(protocol, error_connecting); asio_acceptorPtr->open(protocol, error_connecting); but I always got error. the error code is 1. It means Operation not permitted. Did I miss something? Do I need to delete above socketPtr and acceptorPtr and create new one each time? thanks, -- View this message in context: http://www.nabble.com/socket-reconnection-tp20922241p20922241.html Sent from the Boost - Users mailing list archive at Nabble.com.

2 3

asio - How do I modify code using old ASIO to newer version?
by Jeff Lee 10 Dec '08

10 Dec '08

Hi , I have some code using the old version of ASIO . some code like this: try { while( mWrapped->mSocket.in_avail() > 0 ) { ... but I found that there is no in_avail() method exist in current version. how can I resolve the problem ? Plz dont just give a web link. I'm using the very very slow internet connection.. so , search from internet or even get the document is difficult.

2 1

[Asio] async_connect leaking memory/handles ?
by Jim Methley 10 Dec '08

10 Dec '08

Hello there, New to the list and using Boost Asio. I've implemented an SSL connection using async_connect ok, but find that it seems to leave resources allocated when completed and the SSL connection object is destroyed. The application using the Boost SSL functionality creates a socket connection as required then releases it. Its running on a windows platform with Microsoft Visual Studio 2008 and Boost 1.36.0. The problem can be easily illustrated by simple modification of http://www.boost.org/doc/libs/1_36_0/doc/html/boost_asio/example/ssl/cli ent.cpp to place the main functionality in a loop. Then monitoring the process using TaskManager to display Mem Usage and Handles shows both steadily going up. The number of handles increments by 1,2 or 3 on each async_connect. This happens regardless of whether it actually manages to connect or not. A modification to not use SSL has no effect. A further modification to use a synchronous connect and the program then does not bleed resources. Is this a known problem ? Or is there something which I should be releasing myself ? The actual code I tested is shown below. The relevant parts are: 1) main() line 140: while (true) 2) class client() line 32: simple socket connect (resources released ok) 3) class client() line 41: original async_connect (resources not released ok) Any ideas gratefully received ! /Jim // // client.cpp // ~~~~~~~~~~ // // Copyright (c) 2003-2008 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #include <cstdlib> #include <iostream> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/asio/ssl.hpp> using boost::asio::ip::tcp; enum { max_length = 1024 }; class client { public: client(boost::asio::io_service& io_service, boost::asio::ssl::context& context, boost::asio::ip::tcp::resolver::iterator endpoint_iterator) : simpleSocket_(io_service) ,socket_(io_service, context) { boost::asio::ip::tcp::endpoint endpoint = *endpoint_iterator; // This consumes no resources simpleSocket_.connect(endpoint); // This consumes resources // simpleSocket_.async_connect(endpoint, // boost::bind(&client::handle_connect, this, // boost::asio::placeholders::error, // ++endpoint_iterator)); // This original code consumes resources // socket_.lowest_layer().async_connect(endpoint, // boost::bind(&client::handle_connect, this, // boost::asio::placeholders::error, ++endpoint_iterator)); } void handle_connect(const boost::system::error_code& error, boost::asio::ip::tcp::resolver::iterator endpoint_iterator) { std::cout << "handled connect"; return; if (!error) { socket_.async_handshake(boost::asio::ssl::stream_base::client, boost::bind(&client::handle_handshake, this, boost::asio::placeholders::error)); } else if (endpoint_iterator != boost::asio::ip::tcp::resolver::iterator()) { socket_.lowest_layer().close(); boost::asio::ip::tcp::endpoint endpoint = *endpoint_iterator; socket_.lowest_layer().async_connect(endpoint, boost::bind(&client::handle_connect, this, boost::asio::placeholders::error, ++endpoint_iterator)); } else { std::cout << "Connect failed: " << error << "\n"; } } void handle_handshake(const boost::system::error_code& error) { if (!error) { std::cout << "Enter message: "; std::cin.getline(request_, max_length); size_t request_length = strlen(request_); boost::asio::async_write(socket_, boost::asio::buffer(request_, request_length), boost::bind(&client::handle_write, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } else { std::cout << "Handshake failed: " << error << "\n"; } } void handle_write(const boost::system::error_code& error, size_t bytes_transferred) { if (!error) { boost::asio::async_read(socket_, boost::asio::buffer(reply_, bytes_transferred), boost::bind(&client::handle_read, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } else { std::cout << "Write failed: " << error << "\n"; } } void handle_read(const boost::system::error_code& error, size_t bytes_transferred) { if (!error) { std::cout << "Reply: "; std::cout.write(reply_, bytes_transferred); std::cout << "\n"; } else { std::cout << "Read failed: " << error << "\n"; } } private: tcp::socket simpleSocket_; boost::asio::ssl::stream<boost::asio::ip::tcp::socket> socket_; char request_[max_length]; char reply_[max_length]; }; int main(int argc, char* argv[]) { try { if (argc != 3) { std::cerr << "Usage: client <host> <port>\n"; return 1; } while (true) { std::cout << "Creating service\n"; boost::asio::io_service io_service; boost::asio::ip::tcp::resolver resolver(io_service); boost::asio::ip::tcp::resolver::query query(argv[1], argv[2]); boost::asio::ip::tcp::resolver::iterator iterator = resolver.resolve(query); boost::asio::ssl::context ctx(io_service, boost::asio::ssl::context::sslv23); ctx.set_verify_mode(boost::asio::ssl::context::verify_peer); ctx.load_verify_file("ca.pem"); client c(io_service, ctx, iterator); io_service.run(); } } catch (std::exception& e) { std::cerr << "Exception: " << e.what() << "\n"; } return 0; }

1 1

[Serialization] assertion failure on exit
by Kenny Riddile 09 Dec '08

09 Dec '08

I'm getting the following assertion failure on exit when instantiating certain serializable classes: Assertion failed: NULL != l, file libs\serialization\src\extended_type_info.cpp, line 47 I was finally able to determine a difference between the classes that caused the assertion failure and those that didn't. Here's some code: ////////////////////////////////////////////////////////////////// // Serializable.hpp: class Serializable { public: virtual ~Serializable() = 0; template< typename Archive > void serialize( Archive& /*ar*/, const unsigned int /*version*/ ) { } private: }; inline Serializable::~Serializable() { } BOOST_CLASS_EXPORT( Serializable ) ////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////// // Foo.hpp: struct Foo : Serializable { template< typename Archive > void serialize( Archive& ar, const unsigned int /*version*/ ) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP( Serializable ); } }; BOOST_CLASS_EXPORT( Foo ) ////////////////////////////////////////////////////////////////// The above code does not assert on exit after instantiating a Foo object. If I make Foo not header-only like so: ////////////////////////////////////////////////////////////////// // Foo.hpp: struct Foo : Serializable { Foo(); template< typename Archive > void serialize( Archive& ar, const unsigned int /*version*/ ) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP( Serializable ); } }; BOOST_CLASS_EXPORT( Foo ) ////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////// // Foo.cpp: Foo::Foo() { } ////////////////////////////////////////////////////////////////// then I get the assertion failure on program exit if I so much as instantiate a Foo object.

4 8

asio - how to reuse existing socket descriptor?
by QPlace 09 Dec '08

09 Dec '08

I am porting Win32 C++ application to use boost asio library. In this application I have a client socket that is returned to me from the call to 3-rd party library. Then I am getting data from the connection using WSAAsyncSelect, where the first parameter is the socket handle. My question: Is there any way to use asio library to read data from already established connection where I know the client socket handle? I cannot initiate connection myself, it is only done through 3-rd party library, I only know client socket descriptor. Any help/comments will be greatly appreciated.

2 1