- Boost-users - lists.boost.org

Traversing through a multi_array and accessing the data set...
by Graham Reitz 04 Sep '07

04 Sep '07

How do you access the data in the example below? Thanks much, Graham boost::multi_array<double,2> multi_test; boost::multi_array<double,2>::iterator multi_test_iter; boost::multi_array<double,2>::extent_gen extents; multi_test.resize(extents[2][3]); for (multi_test_iter = multi_test.begin(); multi_test_iter != multi_test.end(); ++multi_test_iter) { // How do you get(set) at the current data set pointed to by multi_test_iter? }

2 2

[Serialization] New user: serializing base class
by Len Berman 04 Sep '07

04 Sep '07

Hi, I am trying to understand the differences between intrusive and non-intrusive style of serialization for derived classes. The classes I want to serialize look like: class Base {} template<class TYPE> class Derived : public Base , public std::vector<TYPE> {} where it is intended that TYPE is a built in C type (int, double, ...) I'm starting by trying to understand the demo.cpp example since that example serializes derived classes. My first goal is to serialize bus_stop_corner and bus_stop_destination directly through the base class. These are serialized through a pointer indirectly when bus_stop_schedule is serialized; however, I've been unable to do this directly. I've gone about it using the pseudo-code in 'Pointers to Objects of Derived Classes'; however, I get the following compilation error: g++ -g demo2.cpp -o demo2 /usr/lib/libboost_serialization.a (I'm using g++ (GCC) 4.1.2 20061115 (prerelease) (Debian 4.1.1-21)) /usr/include/boost/archive/detail/oserializer.hpp: In function $-1òøvoid boost::archive::save(Archive&, T&) [with Archive = boost::archive::text_oarchive, T = bus_stop*]òù: /usr/include/boost/archive/basic_text_oarchive.hpp:78: instantiated from $-1òøvoid boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù /usr/include/boost/archive/detail/interface_oarchive.hpp:78: instantiated from $-1òøArchive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = bus_stop*, Archive = boost::archive::text_oarchive]òù demo2.cpp:164: instantiated from here /usr/include/boost/archive/detail/oserializer.hpp:567: error: invalid application of $-1òøsizeofòù to incomplete type òøboost::STATIC_ASSERTION_FAILURE<false>òù I've also tried by taking the full demo.cpp, and creating a function, save_stop, modeled after save_schedule. This compiles but saves only the base class. This larger piece of code is below, after ++++++++++++++++++. Differences from demo.cpp are marked with //<<<< Obviously, I'm missing something; hopefully, something simple. Any help greatly appreciated. Thanks. --Len /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 // demo.cpp // // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . // Use, modification and distribution is subject to 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 <iomanip> #include <iostream> #include <fstream> #include <string> #include <boost/archive/tmpdir.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> class gps_position { friend std::ostream & operator<<(std::ostream &os, const gps_position &gp); friend class boost::serialization::access; int degrees; int minutes; float seconds; template<class Archive> void serialize(Archive & ar, const unsigned int /* file_version */){ ar & degrees & minutes & seconds; } public: // every serializable class needs a constructor gps_position(){}; gps_position(int _d, int _m, float _s) : degrees(_d), minutes(_m), seconds(_s) {} }; std::ostream & operator<<(std::ostream &os, const gps_position &gp) { return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes << '\'' << gp.seconds << '"'; } ///////////////////////////////////////////////////////////// // One bus stop // // illustrates serialization of serializable members // class bus_stop_corner; class bus_stop_destination; class bus_stop { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_stop &gp); virtual std::string description() const = 0; gps_position latitude; gps_position longitude; template<class Archive> void serialize(Archive &ar, const unsigned int version) { // register all derived classes. ar.register_type(static_cast<bus_stop_corner>(NULL)); ar.register_type(static_cast<bus_stop_destination>(NULL)); ar & latitude; ar & longitude; } protected: bus_stop(const gps_position & _lat, const gps_position & _long) : latitude(_lat), longitude(_long) {} public: bus_stop(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version) = 0; virtual ~bus_stop(){} }; BOOST_IS_ABSTRACT(bus_stop) std::ostream & operator<<(std::ostream &os, const bus_stop &bs) { return os << bs.latitude << bs.longitude << ' ' << bs.description(); } ///////////////////////////////////////////////////////////// // Several kinds of bus stops // // illustrates serialization of derived types // class bus_stop_corner : public bus_stop { friend class boost::serialization::access; std::string street1; std::string street2; virtual std::string description() const { return street1 + " and " + street2; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { // save/load base class information ar & boost::serialization::base_object<bus_stop>(*this); ar & street1 & street2; } public: bus_stop_corner(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version){ // ar << "bus_stop_corner"; // }; bus_stop_corner(const gps_position & _lat, const gps_position & _long, const std::string & _s1, const std::string & _s2 ) : bus_stop(_lat, _long), street1(_s1), street2(_s2) { } }; class bus_stop_destination : public bus_stop { friend class boost::serialization::access; std::string name; virtual std::string description() const { return name; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { description(); ar & boost::serialization::base_object<bus_stop>(*this) & name; } public: bus_stop_destination(){} // virtual void serialize(std::ostream &ar, const unsigned int file_version){ // ar << "bus_stop_destination"; // }; bus_stop_destination( const gps_position & _lat, const gps_position & _long, const std::string & _name ) : bus_stop(_lat, _long), name(_name) { } }; int main(int argc, char *argv[]) { // fill in the data // make a few stops bus_stop_corner *bsc0; bus_stop *bs0 = bsc0 = new bus_stop_corner( gps_position(34, 135, 52.560f), gps_position(134, 22, 78.30f), "24th Street", "10th Avenue" ); std::ofstream ofs("demofile1.txt"); boost::archive::text_oarchive oa(ofs); oa << bs0; } ++++++++++++++++++++++++++++++++++++++ /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 // demo.cpp // // (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com . // Use, modification and distribution is subject to 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 <iomanip> #include <iostream> #include <fstream> #include <string> #include <boost/archive/tmpdir.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> ///////////////////////////////////////////////////////////// // The intent of this program is to serve as a tutorial for // users of the serialization package. An attempt has been made // to illustrate most of the facilities of the package. // // The intent is to create an example suffciently complete to // illustrate the usage and utility of the package while // including a minimum of other code. // // This illustration models the bus system of a small city. // This includes, multiple bus stops, bus routes and schedules. // There are different kinds of stops. Bus stops in general will // will appear on multiple routes. A schedule will include // muliple trips on the same route. ///////////////////////////////////////////////////////////// // gps coordinate // // llustrates serialization for a simple type // class gps_position { friend std::ostream & operator<<(std::ostream &os, const gps_position &gp); friend class boost::serialization::access; int degrees; int minutes; float seconds; template<class Archive> void serialize(Archive & ar, const unsigned int /* file_version */){ ar & degrees & minutes & seconds; } public: // every serializable class needs a constructor gps_position(){}; gps_position(int _d, int _m, float _s) : degrees(_d), minutes(_m), seconds(_s) {} }; std::ostream & operator<<(std::ostream &os, const gps_position &gp) { return os << ' ' << gp.degrees << (unsigned char)186 << gp.minutes << '\'' << gp.seconds << '"'; } ///////////////////////////////////////////////////////////// // One bus stop // // illustrates serialization of serializable members // class bus_stop { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_stop &gp); virtual std::string description() const = 0; gps_position latitude; gps_position longitude; template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & latitude; ar & longitude; } protected: bus_stop(const gps_position & _lat, const gps_position & _long) : latitude(_lat), longitude(_long) {} public: bus_stop(){} virtual ~bus_stop(){} }; BOOST_IS_ABSTRACT(bus_stop) std::ostream & operator<<(std::ostream &os, const bus_stop &bs) { return os << bs.latitude << bs.longitude << ' ' << bs.description(); } ///////////////////////////////////////////////////////////// // Several kinds of bus stops // // illustrates serialization of derived types // class bus_stop_corner : public bus_stop { friend class boost::serialization::access; std::string street1; std::string street2; virtual std::string description() const { return street1 + " and " + street2; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { // save/load base class information ar & boost::serialization::base_object<bus_stop>(*this); ar & street1 & street2; } public: bus_stop_corner(){} bus_stop_corner(const gps_position & _lat, const gps_position & _long, const std::string & _s1, const std::string & _s2 ) : bus_stop(_lat, _long), street1(_s1), street2(_s2) { } }; class bus_stop_destination : public bus_stop { friend class boost::serialization::access; std::string name; virtual std::string description() const { return name; } template<class Archive> void serialize(Archive &ar, const unsigned int version) { description(); ar & boost::serialization::base_object<bus_stop>(*this) & name; } public: bus_stop_destination(){} bus_stop_destination( const gps_position & _lat, const gps_position & _long, const std::string & _name ) : bus_stop(_lat, _long), name(_name) { } }; ///////////////////////////////////////////////////////////// // a bus route is a collection of bus stops // // illustrates serialization of STL collection templates. // // illustrates serialzation of polymorphic pointer (bus stop *); // // illustrates storage and recovery of shared pointers is correct // and efficient. That is objects pointed to by more than one // pointer are stored only once. In such cases only one such // object is restored and pointers are restored to point to it // class bus_route { friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_route &br); typedef bus_stop * bus_stop_pointer; std::list<bus_stop_pointer> stops; template<class Archive> void serialize(Archive &ar, const unsigned int version) { // in this program, these classes are never serialized directly but rather // through a pointer to the base class bus_stop. So we need a way to be // sure that the archive contains information about these derived classes. //ar.template register_type<bus_stop_corner>(); ar.register_type(static_cast<bus_stop_corner *>(NULL)); //ar.template register_type<bus_stop_destination>(); ar.register_type(static_cast<bus_stop_destination *>(NULL)); // serialization of stl collections is already defined // in the header ar & stops; } public: bus_route(){} void append(bus_stop *_bs) { stops.insert(stops.end(), _bs); } }; std::ostream & operator<<(std::ostream &os, const bus_route &br) { std::list<bus_stop *>::const_iterator it; // note: we're displaying the pointer to permit verification // that duplicated pointers are properly restored. for(it = br.stops.begin(); it != br.stops.end(); it++){ os << '\n' << std::hex << "0x" << *it << std::dec << ' ' << **it; } return os; } ///////////////////////////////////////////////////////////// // a bus schedule is a collection of routes each with a starting time // // Illustrates serialization of STL objects(pair) in a non-intrusive way. // See definition of operator<< <pair<F, S> >(ar, pair) and others in // serialization.hpp // // illustrates nesting of serializable classes // // illustrates use of version number to automatically grandfather older // versions of the same class. class bus_schedule { public: // note: this structure was made public. because the friend declarations // didn't seem to work as expected. struct trip_info { template<class Archive> void serialize(Archive &ar, const unsigned int file_version) { // in versions 2 or later if(file_version >= 2) // read the drivers name ar & driver; // all versions have the follwing info ar & hour & minute; } // starting time int hour; int minute; // only after system shipped was the driver's name added to the class std::string driver; trip_info(){} trip_info(int _h, int _m, const std::string &_d) : hour(_h), minute(_m), driver(_d) {} }; private: friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream &os, const bus_schedule &bs); friend std::ostream & operator<<(std::ostream &os, const bus_schedule::trip_info &ti); std::list<std::pair<trip_info, bus_route *> > schedule; template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & schedule; } public: void append(const std::string &_d, int _h, int _m, bus_route *_br) { schedule.insert(schedule.end(), std::make_pair(trip_info(_h, _m, _d), _br)); } bus_schedule(){} }; BOOST_CLASS_VERSION(bus_schedule, 2) std::ostream & operator<<(std::ostream &os, const bus_schedule::trip_info &ti) { return os << '\n' << ti.hour << ':' << ti.minute << ' ' << ti.driver << ' '; } std::ostream & operator<<(std::ostream &os, const bus_schedule &bs) { std::list<std::pair<bus_schedule::trip_info, bus_route *> >::const_iterator it; for(it = bs.schedule.begin(); it != bs.schedule.end(); it++){ os << it->first << *(it->second); } return os; } void save_schedule(const bus_schedule &s, const char * filename){ // make an archive std::ofstream ofs(filename); boost::archive::text_oarchive oa(ofs); oa << s; } //<<<< void save_stop(const bus_stop &s, const char * filename){ // make an archive std::ofstream ofs(filename); boost::archive::text_oarchive oa(ofs); oa.register_type(static_cast<bus_stop_corner* >(NULL)); //ar.template register_type<bus_stop_destination>(); oa.register_type(static_cast<bus_stop_destination* >(NULL)); oa << s; } //>>>> void restore_schedule(bus_schedule &s, const char * filename) { // open the archive std::ifstream ifs(filename); boost::archive::text_iarchive ia(ifs); // restore the schedule from the archive ia >> s; } int main(int argc, char *argv[]) { // make the schedule bus_schedule original_schedule; // fill in the data // make a few stops bus_stop *bs0 = new bus_stop_corner( gps_position(34, 135, 52.560f), gps_position(134, 22, 78.30f), "24th Street", "10th Avenue" ); //<<<< std::string filename1(boost::archive::tmpdir()); filename1 += "/demofile1.txt"; save_stop( *bs0 , filename1.c_str()); //>>>> bus_stop *bs1 = new bus_stop_corner( gps_position(35, 137, 23.456f), gps_position(133, 35, 54.12f), "State street", "Cathedral Vista Lane" ); bus_stop *bs2 = new bus_stop_destination( gps_position(35, 136, 15.456f), gps_position(133, 32, 15.300f), "White House" ); bus_stop *bs3 = new bus_stop_destination( gps_position(35, 134, 48.789f), gps_position(133, 32, 16.230f), "Lincoln Memorial" ); // make a routes bus_route route0; route0.append(bs0); route0.append(bs1); route0.append(bs2); // add trips to schedule original_schedule.append("bob", 6, 24, &route0); original_schedule.append("bob", 9, 57, &route0); original_schedule.append("alice", 11, 02, &route0); // make aother routes bus_route route1; route1.append(bs3); route1.append(bs2); route1.append(bs1); // add trips to schedule original_schedule.append("ted", 7, 17, &route1); original_schedule.append("ted", 9, 38, &route1); original_schedule.append("alice", 11, 47, &route1); // display the complete schedule std::cout << "original schedule"; std::cout << original_schedule; std::string filename(boost::archive::tmpdir()); filename += "/demofile.txt"; // save the schedule save_schedule(original_schedule, filename.c_str()); // ... some time later // make a new schedule bus_schedule new_schedule; restore_schedule(new_schedule, filename.c_str()); // and display std::cout << "\nrestored schedule"; std::cout << new_schedule; // should be the same as the old one. (except for the pointer values) delete bs0; delete bs1; delete bs2; delete bs3; return 0; }

2 1

[Boost.Build] installation problem
by david shaw 04 Sep '07

04 Sep '07

Hi,I go there http://www.boost.org/doc/html/jam/building.htmlI do:C:\Documents and Settings\src\boost\tools\jam\src>build mingw --debug (like explained)A new folder named bin.ntx86.debug is added after I go there http://www.boost.org/doc/html/bbv2/installation.html 1:(done) 2:I do:C:\Documents and Settings\src\boost\tools\build\v2> bjam --versionInstead of seing:Boost.Build V2 (Milestone 11)Boost.Jam 03.1.14 I see:syntax error at EOFBoost.Build V2 (Milestone 11)Boost.Jam 03.1.14 3:I open the user-config.jam file (like explained) and I modify the file, the modification is the following: import toolset : using gcc ;# GCC configuration# Configure gcc (default version) using gcc : : "C:\mingw\bin\g++" ; 4:I copy bjam.exe from C:\Documents and Settings\src\boost\tools\build\v2 to C:\Documents and Settings\src\boost\tools\build\v2\example\hello and I run bjam (like explained):C:\Documents and Settings\src\boost\tools\build\v2\example\hello>bjam I get :C:\Documents and Settings\src\boost\tools\build\v2\kernel\modules.jam:280 :in modules.importIMPORT error:rule gcc unknown in module "toolset."... ...... ... Where is my error(4)? Thanks, David _________________________________________________________________ Téléchargez gratuitement l'économiseur d'écran Les Simson Le film ! http://specials.divertissements.fr.msn.com/lessimpsonlefilm/economiseur.aspx

2 1

Using stringtok with multiarray
by Abhishek V 04 Sep '07

04 Sep '07

Hi My overall goal is to read a csv file and then create a graph out of this. Which can be provided as an input to the boost graph library.For creating vertex set i have used vector and for edges i m making use of multiarray. The sample code snippet is provided below.. (This is not the actual code) /* vector<string> vect; string str="L1,L2,L3,L4,L5"; string str1="L1,0,0,0,0"; string str2="L2,0,0,0,0"; boost::stringtok(vect,str,","); typedef boost::multi_array<string,2> my_array; typedef my_array::index index; int size =vect.size(); my_array A1(boost::extents[size][size]); int i=0; for(index jt=0;jt!=size;jt++) { boost::stringtok(A1[0][jt],str1,","); } The one in Bold gives an error message.. c:\srlgrp\boostlib\boost_1_34_0\boost_1_34_0\boost\pending\stringtok.hpp(103) : error C2039: 'push_back' : is not a member of 'multi_array<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,2,class std::allocator <class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > >' Please help regarding this. Also let me know if this is the best way to perform the task or something else will be better... Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

4 9

BUG/PATCH: Spurious warning in boost::xpressive::detail::enable_reference_tracking
by Bryan Donlan 04 Sep '07

04 Sep '07

Creating a static xpressive regex object referencing statically another regex object causes a spurious (and often extremely long) warning when gcc's -W and -Wall flags are in use. GCC version: version 4.1.3 20070831 (prerelease) (Ubuntu 4.1.2-16ubuntu1) boost version: 1.34.0 and 1.34.1 To demonstrate this bug, build the following on -W -Wall: --- boostbug.cc --- #include <boost/xpressive/xpressive.hpp> int main() { boost::xpressive::sregex r1 = boost::xpressive::digit; boost::xpressive::sregex r2 = *r1; return 0; } --- end boostbug.cc --- The warning output is as follows: /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp: In copy constructor 'boost::xpressive::detail::enable_reference_tracking<Derived>::enable_reference_tracking(const boost::xpressive::detail::enable_reference_tracking<Derived>&) [with Derived = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]': /usr/include/boost/xpressive/detail/core/regex_impl.hpp:63: instantiated from 'boost::xpressive::detail::regex_impl<BidiIter>::regex_impl(const boost::xpressive::detail::regex_impl<BidiIter>&) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:173: instantiated from 'void boost::xpressive::detail::enable_reference_tracking<Derived>::tracking_clear() [with Derived = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:395: instantiated from 'boost::xpressive::detail::tracking_ptr<Type>& boost::xpressive::detail::tracking_ptr<Type>::operator=(const boost::xpressive::detail::tracking_ptr<Type>&) [with Type = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:373: instantiated from 'boost::xpressive::detail::tracking_ptr<Type>::tracking_ptr(const boost::xpressive::detail::tracking_ptr<Type>&) [with Type = boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >]' /usr/include/boost/xpressive/basic_regex.hpp:53: instantiated from 'boost::xpressive::basic_regex<BidiIter>::basic_regex(const boost::xpressive::basic_regex<BidiIter>&) [with BidiIter = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > >]' boostbug.cc:4: instantiated from here /usr/include/boost/xpressive/detail/utility/tracking_ptr.hpp:205: warning: base class 'class boost::enable_shared_from_this<boost::xpressive::detail::regex_impl<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >' should be explicitly initialized in the copy constructor I've attached a trivial patch (against 1.34.0; applies cleanly to 1.34.1) to silence this warning.

2 1

Do we like the same books?
by abir basak 04 Sep '07

04 Sep '07

I just joined Shelfari to connect with other book lovers. Come see the books I love and see if we have any in common. Then pick my next book so I can keep on reading. Click below to join my group of friends on Shelfari! http://www.shelfari.com/Register.aspx?ActivityId=7696512&InvitationCode=7f8… abir basak Shelfari is a free site that lets you share book ratings and reviews with friends and meet people who have similar tastes in books. It also lets you build an online bookshelf, join book clubs, and get good book recommendations from friends. You should check it out. -------- You have received this email because abir basak (abirbasak(a)gmail.com) directly invited you to join his/her community on Shelfari. It is against Shelfari's policies to invite people who you don't know directly. Follow this link (http://www.shelfari.com/actions/emailoptout.aspx?email=boost-users@lists.bo…) to prevent future invitations to this address. If you believe you do not know this person, you may view (http://www.shelfari.com/abirbasak) his/her Shelfari page or report him/her in our feedback (http://www.shelfari.com/Feedback.aspx) section. Shelfari, 616 1st Ave #300, Seattle, WA 98104

1 0

boost, LD_PRELOAD and segfault
by Lorenzo Cavallaro 03 Sep '07

03 Sep '07

Hi all, I'm experiencing something very weird. I'm developing a shared object written in C++ and linked against libboost-serialization-gcc41.so. This dynamic library is preloaded before launching a test program (proftpd). As soon as a try to log into the ftp server using a non-anonymous user, I get a segfault from the child the was handling the client connection. Of course, the same code, without libboost-serialization-gcc41.so linked against is perfectly working. I also removed any serialize method so basically only the libboost header file are included with the library linked as well. Do you guys have any idea of what's going on? Libboost version 1.34.1, gcc version 4.1. I'm going to build the gcc-3.4 version of the library and I'll turn debugging on. TIA, bye Lorenzo PS: of course I tried to debug but what I got was pretty useless. No clue. For instance, strace showed a syscall (gettimeofday) is successfully invoked before the segfault. -- Lorenzo `Gigi Sullivan' Cavallaro <sullivan(a)security.dico.unimi.it> GPG key at http://security.dico.unimi.it/~sullivan/sullivan.asc Until I loved, life had no beauty; I did not know I lived until I had loved. (Theodor Korner) See the reality in your eyes, when the hate makes you blind. (A.H.X)

2 2

[serialization] "unregistered void cast" error -- what does it mean?
by John Pye 03 Sep '07

03 Sep '07

Hi all I have been getting an 'unregistered void cast' *runtime* error message following some apparently unrelated changes to my code. Can anyone possibly clarify the cases when it is necessary to use "void_cast_register" with Boost::Serialization? I think that the error is coming from attempts to serialize this class: class MirrorBundleIndexed : public std::map<MeshIndex, boost::shared_ptr<Mirror> > , public Object { public: typedef boost::shared_ptr<Mirror> valuetype; typedef std::map<MeshIndex,valuetype> container; typedef container::iterator iterator; typedef container::const_iterator const_iterator; ... private: friend class boost::serialization::access; template<class Archive> OPTX_LOCAL void serialize(Archive & ar, const unsigned int version){ ar & boost::serialization::base_object<Object>(*this); ar & boost::serialization::base_object<container>(*this); } }; Cheers JP

2 1

[boost::thread] Problems with condition objects
by Rene Tarantino 03 Sep '07

03 Sep '07

Hi: I'm having a bit of trouble with the implementation of the monitor pattern by means of using mutex and condition classes. I have a scheduler thread and a group of worker threads and the scheduling algorithm waits until some worker notifies that it has done the job. It seems that the call to condition::notify_one() must be in a specific order because if the worker calls notify_one before the scheduler arrives to the waiting line it behaves as if the condition object has lost the previous call to notify_one. Is this behavior the one we must expect? and, if so, can any one share a workaround. Thanks in advance. René

2 1

[regex] Why pattern anchored at buffer end ($) also match for (\x0c)FF, (\x0d)CR
by Chandan Nilange 03 Sep '07

03 Sep '07

Hello, As per PCRE /m modifier $ will match the pattern before any newline. However boost_regex gives back matches before formfeed(\x0c) & CarriagReturn(\x0d) Same is observed for ^ i.e match after newline. Please could anybody let me know what is the right pcre behaviour? I have attached the example for demonstration of the case, using boost_regex Regards, Chandan --------------------------------- Park yourself in front of a world of choices in alternative vehicles. Visit the Yahoo! Auto Green Center. #include <iostream> #include <string> #include "/home/ChandanNilange/work/boost/boost_1_34_0/boost/regex.hpp" // Boost.Regex lib using namespace std; int main( ) { std::string s,sre; //regular expression sre="\x30$"; //Matching string s="\x01\x30\x02\x31\x03\x32\x04\x33\x05\x34\x06\x35\x07\x36\x08\x37\x09\x30\x0a\x39\x0b\x30\x0c\x30\x0d\x3c\x0e\x3d\x0f"; boost::regex re; re.assign(sre, boost::regex_constants::perl); std::string::const_iterator start, end; start = s.begin(); end = s.end(); boost::sregex_iterator it(start, end, re); boost::sregex_iterator it_end; for( ; it != it_end; it++) { cout << "Found Pattern:start:" << std::string((*it)[0].first, (*it)[0].second) << ":end:\n" << "Pattern starts at :" << (*it)[0].first - s.begin() << "\nPattern ends at: " << ((*it)[0].second - 1) - s.begin() << "\nPattern length:" << (*it)[0].length() << endl; } } /************************** Results: Found Pattern:start:0:end: Pattern starts at :17 Pattern ends at: 17 Pattern length:1 Found Pattern:start:0:end: Pattern starts at :21 Pattern ends at: 21 Pattern length:1 Found Pattern:start:0:end: Pattern starts at :23 Pattern ends at: 23 Pattern length:1 ****************************/

3 4