- Boost-users - lists.boost.org

Re: [Boost-users] list serialization with boost
by Brian Wood 22 Nov '12

22 Nov '12

Krzysztof Czainski: >2012/11/22 Olivier Austina <olivier.austina(a)gmail.com> > >> Hello, >> I am a newbie of boost and I want to use it. I would like to serialize a >> list. The list is defined with the following data type: >> >> typedef struct person { >> char *name; >> char *first_name; >> struct person *next; >> } person; >> >> person *list_person; >> > > I'd suggest reorganizing your struct into struct person { std::string > first_name; } and useing std::list<person> list. Then serializing and > other operations would probably be trivial. Shalom Another option would be an intrusive list -- http://www.boost.org/doc/libs/1_52_0/doc/html/intrusive.html . The serialization library in Boost doesn't provide support for intrusive containers, but the C++ Middleware Writer -- http://webEbenezer.net has support for intrusive list and rbtree. If you use std::list, the C++ Middleware Writer has some advantages -- http://webEbenezer.net/comparison.html over the serialization library in Boost. (There are serialization and deserialization tests with std::list there.) -- Brian Ebenezer Enterprises -- so far G-d has helped us. http://webEbenezer.net (651) 251-9384

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[mpl] How to use not_ with has_trivial_destructor metafunction
by Christian Henning 22 Nov '12

22 Nov '12

Hi there, I have troubles compiling the following code with Visual C++ 2010 and boost 1.52. #include <boost/mpl/not.hpp> #include <boost/type_traits/has_trivial_destructor.hpp> #include <boost/utility/enable_if.hpp> template <typename T> void foo( typename boost::enable_if< boost::mpl::not_< boost::has_trivial_destructor< T > > >::type* /*ptr*/ = 0 ) { int i = 9; } int main(int argc, char* argv[]) { foo< int >(); return 0; } The error I'm getting is: error C2770: invalid explicit template argument(s) for 'void foo(boost::enable_if<boost::mpl::not_<boost::has_trivial_destructor<T>>>::type *)' Can someone see what the problem might be? Thanks, Christian

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[Range & c++0x Lambdas] Can this be done?
by Robert Jones 22 Nov '12

22 Nov '12

Can the last line, labelled NOT Ok, be made to work? I think the lambda does not publish its result as a bind does, so I suspect it's hopeless. Any thoughts? Thx, Rob. #include <boost/range/adaptor/transformed.hpp> #include <boost/range/algorithm_ext/push_back.hpp> #include <boost/bind.hpp> #include <vector> #include <algorithm> struct S { int i; }; void f( std::vector<int> & out, std::vector<S> & in ) { using boost::adaptors::transformed; // Ok std::transform( in.begin( ), in.end( ), std::back_inserter( out ), bind( & S::i, _1 ) ); // Ok boost::range::push_back( out, in | transformed( bind( & S::i, _1 ) ) ); // Ok std::transform( in.begin( ), in.end( ), std::back_inserter( out ), []( S & s ) { return s.i; } ); // NOT Ok boost::range::push_back( out, in | transformed( []( S & s ) { return s.i; } ) ); }

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list serialization with boost
by Olivier Austina 22 Nov '12

22 Nov '12

Hello, I am a newbie of boost and I want to use it. I would like to serialize a list. The list is defined with the following data type: typedef struct person { char *name; char *first_name; struct person *next; } person; person *list_person; I have the list built from this structure and I want to serialize it on the hard disk. -- Regards Austina

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[Intrusive] unordered_set and thread safety
by Alexandre Hamez 22 Nov '12

22 Nov '12

Hello, I'm currently using intrusive:: unordered_set in a single threaded application. But now, I need to switch to a multi threaded application. As such, the unordered_set must be protected. I don't want to block the whole table with a single mutex. Thus, it would be fine to have a lock per bucket. Furthermore, intrusive:: unordered_set provides a bucket_traits mechanism to enable some customization. So, my question: is it possible to use bucket_traits to have a lock per bucket? Thank you! -- Alexandre Hamez

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Errors compiling with Boost
by Amos Anderson 21 Nov '12

21 Nov '12

Hello -- I'm having trouble compiling our code on redhat gcc 4.4.6 (full specs below). There are a lot of errors in the output, but paring down the list a bit, some examples are pasted below. This exact same code successfully compiles on several OSX compilers, as well as redhat gcc 4.1.2. I posted this to Boost.Build, and someone informed me I had posted to the wrong list. This person mentioned that: > OSX has gcc-4.2 or clang 3.1 for 10.8. > > The gcc project has done some cleanups of standard library code, eliminating > some implicit dependencies. So you might need to explicitly include the now > missing headers. > > Yours, > > Jürgen Does anybody have any suggestions for which headers I might be missing? I do not have direct access to the machine with these compile errors, so it's hard for me to just fiddle with my code. thanks for any advice! Amos. 1) gcc.compile.c++ pymodule/bin/gcc-4.4.6/release-core/threading-multi/SingleCalculator_BP.o In file included from pymodule/SingleCalculator_BP.cc:13: ../tools/boost/boost/range/algorithm/equal.hpp: In function ‘void core::wrap_vector(const std::string&) [with T = boost::shared_ptr<core::energy::SingleCalculator>, bool noProxy = true]’: pymodule/SingleCalculator_BP.cc:33: instantiated from here ../tools/boost/boost/range/algorithm/equal.hpp:160: error: ‘boost::range’ is not a function, ../tools/boost/boost/python/iterator.hpp:92: error: conflict with ‘template<class Accessor1, class Accessor2> boost::python::api::object boost::python::range(Accessor1, Accessor2)’ pymodule/wrap_vector.hh:68: error: in call to ‘range’ "g++" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -g -pthread -fPIC -Dcore_MPI -Dkiss_fft_scalar=float -Wno-unknown-pragmas -Wstrict-aliasing=2 -fno-strict-aliasing -DBOOST_PYTHON_MAX_ARITY=30 -DBOOST_SYSTEM_DYN_LINK=1 -I"../tools/boost" -I"../tools/python/include/python2.7" -I"/import/rh_software/openmpi-1.4.3/include" -c -o "pymodule/bin/gcc-4.4.6/release-core/threading-multi/SingleCalculator_BP.o" "pymodule/SingleCalculator_BP.cc" 2) <snip> instantiated from here ../tools/boost/boost/mpi/detail/mpi_datatype_oarchive.hpp:51: error: invalid use of incomplete type ‘struct boost::is_enum<float>’ ../tools/boost/boost/type_traits/is_enum.hpp:181: error: declaration of ‘struct boost::is_enum<float>’ <snip> 3) <snip> ../tools/boost/boost/mpi/detail/mpi_datatype_oarchive.hpp: In member function ‘void boost::mpi::detail::mpi_datatype_oarchive::save_override(const T&, int) [with T = long unsigned int]’: ../tools/boost/boost/mpi/detail/mpi_datatype_oarchive.hpp:51: error: template instantiation depth exceeds maximum of 128 (use -ftemplate-depth-NN to increase the maximum) instantiating ‘struct boost::is_enum<long unsigned int>’ <snip> 4) <snip> instantiated from here ../tools/boost/boost/archive/detail/check.hpp:78: error: ‘value’ is not a member of ‘boost::archive::detail::check_object_versioning() [with T = boost::serialization::nvp<float>]::typex <snip> g++ -v Using built-in specs. Target: x86_64-redhat-linux Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre --enable-libgcj-multifile --enable-java-maintainer-mode --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib --with-ppl --with-cloog --with-tune=generic --with-arch_32=i686 --build=x86_64-redhat-linux Thread model: posix gcc version 4.4.6 20110731 (Red Hat 4.4.6-3) (GCC)

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SVN access problem
by Simon West 20 Nov '12

20 Nov '12

Hi, I am being asked for a username and password when attempting to check out Boost anonymously using the following command: $ svn co http://svn.boost.org/svn/boost/trunk boost-trunk This command was copy-pasted directly from the instructions for anonymous read-only access described at https://svn.boost.org/trac/boost/wiki/BoostSubversion. This is holding up my progress in creating a patch - can anyone help? Thanks, Simon.

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[enable_if] Compile Time Member Overloading
by Christian Henning 20 Nov '12

20 Nov '12

Hi there, can someone tell me why the following doesn't compile with VS2010 SP1? #include <boost/mpl/and.hpp> #include <boost/type_traits/is_same.hpp> #include <boost/utility/enable_if.hpp> using namespace boost; struct foo { void bla() { read_data_24<int, int>(); } template< typename T1 , typename T2 > void read_data_24( typename enable_if< mpl::and_< mpl::true_ , mpl::bool_< is_same< T1, T2 >::type::value > > >::type* /* ptr */ = 0 ) { int i = 9; } }; int main(int argc, char* argv[]) { return 0; } I get the error: 1>gil_test_vc10.cpp(25): error C2039: 'type' : is not a member of 'boost::enable_if<Cond>' 1> with 1> [ 1> Cond=boost::mpl::and_<boost::mpl::true_,boost::mpl::bool_<false>> 1> ] I tried a couple of hours to have make is happen but I don't get it. Thanks, Christian

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[ASIO] "perf" shows overhead of function calls is very high
by Junchang Wang 19 Nov '12

19 Nov '12

Hi list, I'm new to Boost.asio and am solving scaling problems of a Openflow (TCP based) server. We are using one single io_service for packets receiving and transmitting. A thread pool calling io_service::run() processes HTTP requests. A multi-core server is used. I found we can't get benefits from increasing the size of thread pool when it's size is larger than 6. In other words the system doesn't scale any more on more than 6 cores. I checked the program carefully and can make sure there's no lock contention. I profile the program with Linux perf, and it turns out up to 36% of CPU time is wasted in function calls. 36.39% : 0000000000103300 <boost::detail::function::void_function_obj_invoker3<vigil::openflow::v1::construct_and_load<vigil::openflow::v1::ofp_packet_out, vigil:: : BOOST_FUNCTION_TEMPLATE_PARMS : > : struct BOOST_FUNCTION_VOID_FUNCTION_OBJ_INVOKER : { : static BOOST_FUNCTION_VOID_RETURN_TYPE : invoke(function_buffer& function_obj_ptr BOOST_FUNCTION_COMMA 0.02 : 103300: push %rbp 99.66 : 103301: mov %rsp,%rbp 0.00 : 103304: push %r12 0.04 : 103306: mov %rcx,%r12 I printed out the call stack (attached at the tail of this email). It seems for a single packet processing there are more than 30 function calls within Boost. Can that explain why the CPU time on function calls is so high? Are there some ways to avoid this kind of cost? Thanks a lot. --Junchang ================ #0 vigil::openflow::Openflow_datapath::send (this=<optimized out>, msg=0x7ffff567f920) at ../../../../src/coreapps/openflow/openflow-datapath.cc:199 #1 0x00007ffff4c50724 in vigil::openflow::Openflow_datapath::handle_handshake (this=0x7ffff007dd80, e=...) at ../../../../src/coreapps/openflow/openflow-datapath.cc:305 #2 0x00007ffff4c5086a in vigil::openflow::Openflow_datapath::handle_message (this=0x7ffff007dd80, msg=0x7ffff567f920) at ../../../../src/coreapps/openflow/openflow-datapath.cc:228 #3 0x00007ffff4c50a39 in vigil::openflow::Openflow_datapath::recv_cb (this=0x7ffff007dd80, bytes_transferred=<optimized out>) at ../../../../src/coreapps/openflow/openflow-datapath.cc:164 #4 0x00007ffff7bad130 in operator() (a0=<optimized out>, this=0x7ffff007d4b8) at /usr/include/boost/function/function_template.hpp:1013 #5 vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >::handle_recv ( this=0x7ffff007d480, ec=..., bytes_transferred=<optimized out>) at ../../../src/lib/connection.cc:185 #6 0x00007ffff7bb5fba in call<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > >, boost::system::error_code const, unsigned long const> (b2=@0x7ffff568fa10: 8, b1=..., u=..., this=0x7ffff568f9e0) at /usr/include/boost/bind/mem_fn_template.hpp:271 #7 operator()<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > > (u=..., this=0x7ffff568f9e0, a2=@0x7ffff568fa10: 8, a1=...) at /usr/include/boost/bind/mem_fn_template.hpp:286 #8 operator()<boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, const boost::system::error_code&, const long unsigned int&>, boost::_bi::list2<const boost::system::error_code&, const long unsigned int&> > (a=<synthetic pointer>, f=..., this=0x7ffff568f9f0) at /usr/include/boost/bind/bind.hpp:392 #9 operator()<boost::system::error_code, long unsigned int> (a2=@0x7ffff568fa10: 8, a1=..., this=0x7ffff568f9e0) at /usr/include/boost/bind/bind_template.hpp:102 #10 operator() (this=0x7ffff568f9e0) at /usr/include/boost/asio/detail/bind_handler.hpp:97 #11 asio_handler_invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > ( function=<error reading variable: access outside bounds of object referenced via synthetic pointer>) at /usr/include/boost/asio/handler_invoke_hook.hpp:64 #12 boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > (function=..., context=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #13 0x00007ffff7bb637b in asio_handler_invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> (this_handler=0x7ffff568fbf0, function=...) at /usr/include/boost/asio/detail/bind_handler.hpp:132 #14 invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > (context=..., function=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #15 boost::asio::detail::strand_service::dispatch<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > (this=0x7ffff0001560, impl=@0x7ffff568fbb0: 0x7ffff0047d80, handler=...) at /usr/include/boost/asio/detail/impl/strand_service.hpp:97 #16 0x00007ffff7bb66fa in dispatch<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > ( handler=<error reading variable: access outside bounds of object referenced via synthetic pointer>, this=0x7ffff568fba8) at /usr/include/boost/asio/strand.hpp:159 #17 operator()<boost::system::error_code, long unsigned int> (arg2=<synthetic pointer>, arg1=..., this=0x7ffff568fba8) at /usr/include/boost/asio/detail/wrapped_handler.hpp:65 #18 operator()<boost::system::error_code, long unsigned int> (arg2=<optimized out>, arg1=..., this=0x7ffff568fba0) at ../../../src/lib/connection.cc:64 #19 operator() (this=0x7ffff568fba0) at /usr/include/boost/asio/detail/bind_handler.hpp:97 #20 asio_handler_invoke<boost::asio::detail::binder2<vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > >, boost::system::error_code, unsigned long> > (function=<error reading variable: access outside bounds of object referenced via synthetic pointer>) at /usr/include/boost/asio/handler_invoke_hook.hpp:64 #21 invoke<boost::asio::detail::binder2<vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > >, boost::system::error_code, unsigned long>, vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > > > (function=..., context=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #22 boost::asio::detail::reactive_socket_recv_op<boost::asio::mutable_buffers_1, vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > > >::do_complete (owner=0x6d6b30, base=<optimized out>) at /usr/include/boost/asio/detail/reactive_socket_recv_op.hpp:106 #23 0x0000000000487343 in complete (owner=..., this=0x7ffff007d510) at /usr/include/boost/asio/detail/task_io_service_operation.hpp:35 #24 boost::asio::detail::task_io_service::do_one (this=0x6d6b30, lock=..., this_idle_thread=0x7ffff568fdd0) at /usr/include/boost/asio/detail/impl/task_io_service.ipp:278 #25 0x00000000004874b0 in boost::asio::detail::task_io_service::run (this=0x6d6b30, ec=...) at /usr/include/boost/asio/detail/impl/task_io_service.ipp:130 #26 0x00000000004875c9 in boost::asio::io_service::run (this=0x6d68f8) at /usr/include/boost/asio/impl/io_service.ipp:57 #27 0x00007ffff7971ce9 in thread_proxy () from /usr/lib/libboost_thread.so.1.46.1 #28 0x00007ffff5f2ee9a in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0 #29 0x00007ffff6237cbd in clone () from /lib/x86_64-linux-gnu/libc.so.6 #30 0x0000000000000000 in ?? ()

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code review please? [boost::asio]
by Littlefield, Tyler 18 Nov '12

18 Nov '12

hello all: I was curious if some boost::asio guru would mind checking this out. I just posted my code in, I'd like to know if there's anything that could be done better. Thanks, //client.h #pragma once #include <queue> #include <boost/asio.hpp> #include <boost/bind.hpp> #include "ClientBuffer.h" class Client { protected: boost::asio::ip::tcp::socket _socket; boost::asio::io_service &_service; std::queue<ClientBuffer*> _buffers; bool _writing; void StartWrite(); void HandleWrite(const boost::system::error_code& error); public: Client(boost::asio::io_service &service); ~Client(); virtual boost::asio::ip::tcp::socket& GetSocket(); virtual void Start() = 0; void Write(const char* data); void Write(void* data, unsigned int size); void Write(const std::string &data); }; //client.cpp #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "ClientBuffer.h" Client::Client(boost::asio::io_service &service): _service(service), _socket(service), _writing(false) { } Client::~Client() { } void Client::StartWrite() { //we don't write if we're already writing. We just content ourselves with having pushed the message to the queue. if (_writing) { return; } //we're writing now. _writing = true; ClientBuffer* buffer = NULL; buffer = _buffers.front(); boost::asio::async_write(_socket, boost::asio::buffer(buffer->GetBuffer(), buffer->GetSize()), boost::bind(&Client::HandleWrite, this, boost::asio::placeholders::error)); } void Client::HandleWrite(const boost::system::error_code& error) { if (_buffers.empty()) { _writing = false; return; } ClientBuffer* buffer = _buffers.front(); _buffers.pop(); if (buffer) delete buffer; if (_buffers.empty()) _writing = false; else StartWrite(); } boost::asio::ip::tcp::socket& Client::GetSocket() { return _socket; } void Client::Write(const char* data) { ClientBuffer* buffer = new ClientBuffer(data); _buffers.push(buffer); StartWrite(); } void Client::Write(void* data, unsigned int size) { ClientBuffer* buffer = new ClientBuffer(data, size); _buffers.push(buffer); StartWrite(); } void Client::Write(const std::string &data) { ClientBuffer* buffer = new ClientBuffer(data); _buffers.push(buffer); StartWrite(); } //TelnetClient.h /* *this client is responsible for handling the telnet protocol. */ #pragma once #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "ClientBuffer.h" class TelnetClient:public Client { int _state; boost::asio::streambuf _buffer; public: virtual void Start(); void Read(); void HandleRead(const boost::system::error_code& error); void HandleCommand(const std::string &line); }; //TelnetClient.cpp #include <string> #include <istream> #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "TelnetClient.h" void TelnetClient::Start() { Write("Welcome to SapphireMud.\n"); Write("Use load <player> <password> to load a character.\n"); Write("Use create <player> <password> to create a new player.\n"); _state = 1; Read(); } void TelnetClient::Read() { boost::asio::async_read_until(_socket, _buffer, '\n', boost::bind(&TelnetClient::HandleRead, this, boost::asio::placeholders::error)); } void TelnetClient::HandleRead(const boost::system::error_code& error) { char buffer[2048]; if (error) { //do something here return; } std::istream input(&_buffer); input.getline(buffer, 2048); HandleCommand(buffer); Read(); } void TelnetClient::HandleCommand(const std::string &line) { Write("I don't understand that!\n"); } -- Take care, Ty http://tds-solutions.net The aspen project: a barebones light-weight mud engine: http://code.google.com/p/aspenmud He that will not reason is a bigot; he that cannot reason is a fool; he that dares not reason is a slave.

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