June 2009 - Boost-users - lists.preview.boost.org

boost::serialization and PHP websites
by KessiMC 17 Jun '09

17 Jun '09

Hi everyone Currently, I'm using boost serialization for some of my configuration files (XML format). Some time ago, it became necessary to edit these files using a web interface in PHP. As I could not think of a suitable method to deserialize such an XML file to PHP (with all object references, etc.), I wrote a C++ program generating HTML code, allowing some simple configuration tasks. Even though this worked as a quick and dirty solution, I do not intend to support such a proprietary workaround for too long. Much more comfortable would it be to deserialize the XML file to PHP classes or, with JSP or ASP.NET websites, Java and C# classes. Does anyone of you know of such libraries for crossing the website/C++ line? Or should I use another serialization library? Currently, I consider the boost serialization a de-facto standard for C++ serialization issues. Thanks for any reply and best regards Pascal Kesseli -- View this message in context: http://www.nabble.com/boost%3A%3Aserialization-and-PHP-websites-tp23770268p… Sent from the Boost - Users mailing list archive at Nabble.com.

3 4

[pool] Crash when attempting to call malloc (1.32)
by James Madison 17 Jun '09

17 Jun '09

I am experiencing a very rare crash with boost::pool, when attempting to call malloc(), using boost 1.32. Specifically: In the header: boost::object_pool<unsigned long long> m_cdPool; In the code in Thread 1: unsigned long long key* = m_cdPool.malloc(); In the code in Thread 2: random_structure->memoryPool->free(...); I am crashing on a call to simple_segregated_storage<unsigned int>::malloc() within boost, specifically in the following method, where at the end of the method ret contains an inaccessable memory address. // pre: !empty() void * malloc() { void * const ret = first; // Increment the "first" pointer to point to the next chunk first = nextof(first); return ret; } I am wondering if anyone has experienced anything similar, and knows what might be happening. Also, about threads. This is being malloced/free in two separate threads, however I sort of assumed that pool was thread safe because of discussion about using boost::thread instead of their current scheme for thread safety on another mailing list. Was my assumption wrong, i.e. pool is not thread safe? (I am a little hesitant to blame this completely on threading without searching a bit elsewhere because of the way the three threads operate, there is very little chance they are stomping over the pool, and the other threads are also all in wait states when this occurs)

3 2

pool allocator based on element type instead of size?
by Kenny Riddile 17 Jun '09

17 Jun '09

I've found myself wanting something similar to boost::fast_pool_allocator, but with the following syntax for releasing memory: using namespace boost; std::list< T, fast_pool_allocator<T> > myList; // Note that second template parameter is T, not sizeof(T). // Basically I guess I just want a pool per type, even if // two types have the same size. singleton_pool< fast_pool_allocator_tag, T >::release_memory(); Is there a reason why this isn't doable that I should know about before I try to implement it? Has something similar already been done (even if it's from outside the Boost community) so I don't reinvent the wheel? Thanks, Kenny Riddile

1 0

[Q] boost::spirit BOOST_FUSION_ADAPT_STRUCT error
by V S P 17 Jun '09

17 Jun '09

Hello, I am attempting to parse FuncName(arg1,arg2,... argN) with Spirit, such that args are saved in a vector and func name is saved into a funct_nm I am just in the beginning of this (I have not learned yet how to construct a grammar that allows comma delimited args within braces ) But running into a compilation error on line (std::string, funct_nm) within BOOST_FUSION_ADAPT_STRUCT I am using mini_xml1.cpp as an example Would like to ask for help/pointers to resolve it. I want to mention that my project on boost 1.38 and also includes json_spirit which uses ( I am guessing the 'classic version' of spirit). thank you in advance, Vlad --------------------------------------- #include <json_spirit.h> /* boost spirit parser specifics START */ #include <boost/config/warning_disable.hpp> #include <boost/spirit/include/qi.hpp> #include <boost/spirit/include/phoenix_core.hpp> #include <boost/spirit/include/phoenix_container.hpp> #include <boost/spirit/include/phoenix_statement.hpp> #include <boost/spirit/include/phoenix_object.hpp> #include <boost/spirit/include/phoenix_operator.hpp> #include <iostream> #include <string> #include <complex> /* boost spirit parser specifics end */ using namespace std; using namespace boost::spirit; using namespace boost::spirit::qi; using namespace boost::spirit::ascii; using namespace boost::spirit::arg_names; namespace fusion = boost::fusion; namespace phoenix = boost::phoenix; //VP do not use this namespace,it is clashes with //regular boost //using namespace boost::spirit::arg_names; /* using phoenix::at_c; using boost::phoenix::ref; using boost::phoenix::push_back; using boost::phoenix::val; using boost::phoenix::construct; */ using namespace json_spirit; struct cmdfunct_2arg; //an argument of a function typedef boost::variant< boost::recursive_wrapper<cmdfunct_2arg> , std::string > t_cmd_arg; //function with name and a list of arguments struct cmdfunct_arg { std::string funct_nm; std::vector<t_cmd_arg> args; }; // We need to tell fusion about cmdfunct struct // to make it a first-class fusion citizen //[tutorial_xml1_adapt_structures BOOST_FUSION_ADAPT_STRUCT( cmdfunct_arg, (std::string, funct_nm) (std::vector<t_cmd_arg>, args) ) -- V S P toreason(a)fastmail.fm -- http://www.fastmail.fm - Does exactly what it says on the tin

3 3

Visual studio 2008 problem with linker or compiler (depending on release or debug version)...
by Ozgur Ozturk 16 Jun '09

16 Jun '09

Hi, I have installed boost libraries and headers using the installer from: http://www.boostpro.com/download Then in visual studio I create an empty c++ project and added the chat_server.cpp and chat_message.hpp code from http://www.boost.org/doc/libs/1_39_0/doc/html/boost_asio/examples.html (I wish there was a code download link by the way, I struggled some because of some characters introduced in copy paste) Then I added "C:\Program Files\boost\boost_1_38" to include directories and "C:\Program Files\boost\boost_1_38\lib" to additional library directories (similar to description in the last two sections of this tutorial: http://blog.emptycrate.com/node/421 , but without property sheets, only on project properties.) Now the errors. If I try to build a release version it says: .\chat_server.cpp(17) : fatal error C1083: Cannot open include file: 'boost/bind.hpp': No such file or directory but If I try to build a debug version it says: LINK : fatal error LNK1104: cannot open file 'libboost_system-vc90-mt-gd-1_38.lib' I have a 'libboost_system-vc90-mt-*s*gd-1_38.lib' not 'libboost_system-vc90-mt-gd-1_38.lib' in my lib folder... Thanks in advance, Ozgur (Oscar) Ozturk www.DrOzgur.com +1 (614) 805-4370

2 1

Problem with boost::bind usage
by Zachary Turner 16 Jun '09

16 Jun '09

Is there a technical limitation preventing this from working? int __stdcall VirtualUnlock(void*, size_t); void f() { std::list<void*> locked_buffers; size_t size; std::for_each(locked_buffers.begin(), locked_buffers.end(), boost::bind(VirtualUnlock, boost::lambda::_1, size)); } Irrelevant code snipped for brevity. I get the error It complains about how it can't find F::result_type in bind_template.hpp line 15, with F = int (__stdcall*)(void*, size_t) If I change it to int __stdcall VirtualUnlock(void*, size_t); void f() { std::list<void*> locked_buffers; size_t size; std::for_each(locked_buffers.begin(), locked_buffers.end(), boost::bind(boost::function<int(void*,size_t)>(VirtualUnlock), boost::lambda::_1, size)); } it works, but this is much uglier and I'd rather avoid it.

2 1

lambda::throw_exception fails
by KessiMC 16 Jun '09

16 Jun '09

Hi everyone Be it that this code is working: try { throw InterfaceTimeoutException(); } catch (const std::exception &ex) { cout << ex.what() << endl; } However, trying this: try { lambda::throw_exception(constructor<InterfaceTimeoutException> ())(); } catch (const std::exception &ex) { cout << ex.what() << endl; } ends up with my programm crashing (Exit code 3). What am I missing here? Thanks for any reply and best regards Pascal -- View this message in context: http://www.nabble.com/lambda%3A%3Athrow_exception-fails-tp24063172p24063172… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

Problem using boost::asio::ip::address::from_string
by Matheus Araújo Aguiar 16 Jun '09

16 Jun '09

Hello boost-users, I'm using boost::asio::ip::address in a client-server application and i'm having a strange behaviour when using the member method *from_string*. The method isn't working correctly(or doing any work at all), since after calling it, nothing changes. Bellow there's a code that reproduces the problem. #include <boost/asio.hpp> #include <iostream> int main() { char ip[15]; printf("type ip please\n"); std::cin >> ip; boost::asio::ip::address a; printf("address1 before member method is called %s\n", a.to_string().data()); a.from_string(ip); boost::asio::ip::address b(a); printf("address1 %s from string %s\n", a.to_string().data(), ip); printf("address2 %s from address1 %s\n", b.to_string().data(), a.to_string().data()); return 0; } Can anyone see what is possibly wrong with the code? Thanx in advance! -- Matheus Araújo Aguiar Computer Scientist matheus.pit(a)gmail.com

2 2

Memory manager/allocator
by Daniele Barzotti 16 Jun '09

16 Jun '09

Hi, I'm sorry if the question goes in OT. I'm searching for a simple cross platform memory manager/allocator library/class to simply allocate/read/write blocks of memory. I googled around and I found some projects: http://code.google.com/p/stdext/ http://memory-mgr.sourceforge.net/ there is also boost.interprocess but I don't need its complexity. I'd like to know if there is a well-known and used one. Thanks in advance. Daniele.

3 8

[BGL] List of edges as property type
by caligulaemperorofrome＠yahoo.com 16 Jun '09

16 Jun '09

I'm trying to add a "list of edges" as an edge property type like so. typedef adjacency_list < listS, vecS, directedS > Traits; typedef adjacency_list < listS, vecS, directedS, vertex_properties, property < edge_list_t, std::list<Traits::edge_descriptor>, edge_properties > > > graph_t; But the compiler says : error: ‘edge_list_t’ was not declared in this scope So I think I need to add edge_list_t to the set of property tags. I think there is a method like BOOST_INSTALL PROPERTY ( edge_list_t ). But I think I read somewhere that thats the old way. Can someone tell me the new way to do it? PS: How can I tell which version of boost I am using? Thanks - Caligula

2 1