malloc induit une boucle infinie

0x6a6453d1  <+0x0001>         mov    %esp,%ebp
0x6a6453d3  <+0x0003>         sub    $0x28,%esp
0x6a6453dd  <+0x000d>         mov    %ebx,-0xc(%ebp)
0x6a6453e0  <+0x0010>         mov    %esi,-0x8(%ebp)
0x6a6453e3  <+0x0013>         mov    0xc(%ebp),%esi
0x6a6453e6  <+0x0016>         mov    %edi,-0x4(%ebp)
0x6a6453e9  <+0x0019>         mov    0x10(%ebp),%edi
0x6a6453d6  <+0x0006>         movl   $0xd0,(%esp)
0x6a6453ec  <+0x001c>         call   0x6a646b90 (malloc)
0x6a6453f3  <+0x0023>         mov    %eax,%ebx

0x610c34f9          push   %ebx
0x610c34fa  <+0x0001>         push   %edx
0x610c34fb  <+0x0002>         mov    %fs:0x4,%ebx
0x610c3502  <+0x0009>         mov    $0x1,%eax
0x610c3507  <+0x000e>         xchg   %eax,-0x24d8(%ebx)
0x610c350d  <+0x0014>         mov    %eax,-0x24dc(%ebx)
0x610c3513  <+0x001a>         test   %eax,%eax
0x610c3515  <+0x001c>         je     0x610c351e <_sigfe+37>
0x610c3517  <+0x001e>         call   0x61077680 (yield)
0x610c351c  <+0x0023>         jmp    0x610c3502 <_sigfe+9>
0x610c351e  <+0x0025>         mov    $0x4,%eax
0x610c3523  <+0x002a>         xadd   %eax,-0x24d4(%ebx)
0x610c352a  <+0x0031>         lea    0x610c3545,%edx
0x610c3530  <+0x0037>         xchg   %edx,0xc(%esp)
0x610c3534  <+0x003b>         mov    %edx,(%eax)
0x610c3536  <+0x003d>         incl   -0x24e0(%ebx)
0x610c353c  <+0x0043>         decl   -0x24d8(%ebx)
0x610c3542  <+0x0049>         pop    %edx
0x610c3543  <+0x004a>         pop    %ebx
0x610c3544  <+0x004b>         ret

0x61077680          sub    $0xc,%esp
0x61077683  <+0x0003>         call   0x61159f38 (SwitchToThread@0)
0x61077688  <+0x0008>         call   0x61159f38 (SwitchToThread@0)
0x6107768d  <+0x000d>         add    $0xc,%esp
0x61077690  <+0x0010>         jmp    0x61159f38 (SwitchToThread@0)
0x61077695  <+0x0015>         lea    0x0(%esi,%eiz,1),%esi
0x61077699  <+0x0019>         lea    0x0(%edi,%eiz,1),%edi

4,080 bytes in 1 blocks are possibly lost in loss record 5,805 of 5,874
==4617==    at 0x4C27870: memalign (vg_replace_malloc.c:581)
==4617==    by 0x4C278C9: posix_memalign (vg_replace_malloc.c:709)
==4617==    by 0x737233B: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.2800.6)
==4617==    by 0x7373860: g_slice_alloc (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.2800.6)
==4617==    by 0x7CE4186: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7CE4238: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7D05A6A: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7D08361: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7D0C17F: g_type_add_interface_static (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0xE3C9C65: atk_no_op_object_get_type (in /usr/lib/x86_64-linux-gnu/libatk-1.0.so.0.9.1)
==4617==    by 0xE3C9C8D: atk_no_op_object_new (in /usr/lib/x86_64-linux-gnu/libatk-1.0.so.0.9.1)
==4617==    by 0xD706C8D: ??? (in /usr/lib/libgtk-x11-2.0.so.0.2400.4)
==4617== 
==4617== 4,080 bytes in 1 blocks are possibly lost in loss record 5,806 of 5,874
==4617==    at 0x4C27870: memalign (vg_replace_malloc.c:581)
==4617==    by 0x4C278C9: posix_memalign (vg_replace_malloc.c:709)
==4617==    by 0x737233B: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.2800.6)
==4617==    by 0x7373860: g_slice_alloc (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.2800.6)
==4617==    by 0x7373915: g_slice_alloc0 (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.2800.6)
==4617==    by 0x7D0C398: g_type_create_instance (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7CEA76B: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7CED388: g_object_newv (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7CEE320: g_object_new_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x7CEE620: g_object_new (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.2800.6)
==4617==    by 0x5375FD9: ??? (in /usr/lib/libQtGui.so.4.7.2)

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    /***************************************************************************** on charge la liste ****/
    liste = new QComboBox();
    liste->setParent(this);
    liste->setGeometry(20,20,350,30);
    liste->setEnabled(true);
    liste->addItem(QString("fichiers disponibles"));

    struct dirent *lecture;
        
	DIR *rep;
        rep = opendir("./files" );
        while ((lecture = readdir(rep))) {
            std::string ext = lecture->d_name;

            if(ext != "." && ext != "..")
                if(strcmp(ext.substr((int)strlen(ext.c_str())-3,3).c_str(),"url") == 0)
                    liste->addItem(QString(get_string(lecture->d_name)));
        }
        closedir(rep);

    liste->show();

    /***************************************************************************** on charge la zone texte ****/
    infos = new QTextEdit();
    infos->setParent(this);
    infos->setGeometry(20,60,350,180);
    infos->setText(QString(get_string("Liste chargée.")));
    infos->show();

    /***************************************************************************** on charge le bouton ****/
    press = new QPushButton();
    press->setParent(this);
    press->setGeometry(20,250,70,30);
    press->setText(QString(get_string("Charger")));
    press->show();

    stop = new QPushButton();
    stop->setParent(this);
    stop->setGeometry(20,250,70,30);
    stop->setText(QString(get_string("Stop")));
    stop->hide();


    /***************************************************************************** on charge la barre ****/
    barre = new QProgressBar();
    barre->setParent(this);
    barre->setGeometry(100,250,270,30);
    barre->setValue(0);
    barre->show();

    /***************************************************************************** déclarations signaux/slots ****/
    connect(press, SIGNAL(clicked()), this, SLOT(s_clicked()));
    connect(stop, SIGNAL(clicked()), this, SLOT(stop_clicked()));
    connect(liste,SIGNAL(currentIndexChanged(QString)), this, SLOT(s_liste_select(QString)));
    selectedProgram = new QString("");
    statut = false;
    bar_value = 0;

}

void MainWindow::s_clicked()
{
    statut = true;
    press->hide(); //bouton
    stop->show();  //bouton
    infos->setText(QString(get_string("Etablissement de la connexion...")));
    this->update();
    this->repaint();


    // la boucle infinie apparaît lors de l'appel de la fonction mmsx_connect()
    mmsx_t * tmp = mmsx_connect(0, 0, "mms://site.com/video.wmv", 8*1024*300);
    
    if( inst == NULL )
    {
        QMessageBox message(QMessageBox::Information, "alerte", "connexion échouée");
        message.exec();
        std::cout << "Erreur lors de la connexion au flux." <<std::endl;
        return;
    }
}

Il y a d'autres instructions après le test if(), mais comme elles ne sont jamais exécutées je ne les ai pas inclues pour que ce soit plus léger à lire.

#include <libmms/mmsx.h>
#include <stdio.h>
#include <iostream>
#include <string>
#include <sys/types.h>
#include <dirent.h>
#include <math.h>
#include <time.h>
#include <sstream>

int main()
{

	float bar_value = 0;
	mmsx_t * inst =  mmsx_connect(NULL, NULL, "mms://a988.v101995.c10199.e.vm.akamaistream.net/7/988/10199/3f97c7e6/ftvigrp.download.akamai.com/10199/cappuccino/production/publication/Autre/Autre/2011/S37/J5/313308_desparolesetdesactes_20110915.wmv", 8*1024*300);

    if( inst == NULL )
    {
            std::cout << "Erreur lors de la connexion au flux." <<std::endl;
            return 1;
    }

    std::cout << "Maintenant connecté." << std::endl;

    FILE * pFile;
    pFile = fopen ("file.wmv","w");
    if (pFile==NULL)
    {
            std::cout << "Erreur lors de la création du nouveau fichier." <<std::endl;
            return 1;
    }


    int remaining =  mmsx_get_length(inst) - mmsx_get_current_pos(inst);
    int remaining_old = mmsx_get_length(inst);
    int ret;
    char * data = new char[1024];

    while(bar_value<100)
    {
            ret = mmsx_read(0, inst, data, 1024);

            if(ret < 0)
            {
                    std::cout << "Le fichier a été trouvé mais ne peut être lu." << std::endl;
                    return 1;
            }


            fwrite (data , 1 , 1024 , pFile );

            bar_value = ((float)(mmsx_get_length(inst) - remaining)/mmsx_get_length(inst)*100);
            int total = mmsx_get_length(inst);
            int parcouru = mmsx_get_current_pos(inst);

            // créer un flux de sortie
                std::ostringstream oss1;
                std::ostringstream oss2;
             // écrire un nombre dans le flux
                oss1 << total/(1024*1024);
                oss2 << parcouru/(1024*1024);
             // récupérer une chaîne de caractères
                std::string total2 = oss1.str();
                std::string parcouru2 = oss2.str();

            remaining_old = remaining;
            remaining = mmsx_get_length(inst) - mmsx_get_current_pos(inst);

    }

    delete [] data;

    mmsx_close (inst);
    std::cout << "Connexion terminée." << std::endl;
    fclose (pFile);

    return 0;
}