about textview (gtk_text_buffer_insert_with_tags cause segmentaion fault)

["朱碧岑"<zhubicen gmail com>]

Hi all ,
When I insert some text to textview in a thread in the following code(myThread::run) . it will segmentation 
fault . 
Could someone help me to fix this issue.
Any comments and suggestion will be welcomed.

bzhu

#include <gtk/gtk.h>
#include <wchar.h>
#include <string.h>
#include <pthread.h>
GtkWidget* tv;
GtkTextTag* tag;
#include <assert.h>
class Thread
{
public:
    Thread();
    void start();
    virtual void run();
private:
    pthread_t   m_hThread;
};
Thread::Thread()
{
}
static void* _ou_thread_proc(void* param) 
{
    pthread_setcancelstate(PTHREAD_CANCEL_ENABLE,NULL);
    pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS,NULL);
    Thread* tp = (Thread*)param;
    tp->run();
    pthread_exit(NULL);
    return NULL;
}
void Thread::start()
{
    int iret = pthread_create( &m_hThread, NULL, _ou_thread_proc,this);
    assert(iret == 0);
}
void Thread::run() 
{
}
class myThread:public Thread
{
public :
    void run()
        {
            g_print("Thread is running\n");
            //Code belowe will cause the segmentation fault
            gdk_threads_enter();
            GtkTextBuffer* tb = gtk_text_view_get_buffer(GTK_TEXT_VIEW(tv));
            GtkTextIter end;
            gtk_text_buffer_get_end_iter(GTK_TEXT_BUFFER(tb),&end);
            gchar text[] = "Thread is running\n";
            gtk_text_buffer_insert_with_tags(GTK_TEXT_BUFFER(tb),&end,text,-1,tag);//segmentaion fault.
            gdk_threads_leave();            
            
        }
};
void* thread_proc(void* param)
{
    gdk_threads_enter();
    GtkTextBuffer* tb = gtk_text_view_get_buffer(GTK_TEXT_VIEW(tv));
    GtkTextIter end;
    gtk_text_buffer_get_end_iter(GTK_TEXT_BUFFER(tb),&end);
    gchar text[] = "Thread is running\n";
    gtk_text_buffer_insert_with_tags(GTK_TEXT_BUFFER(tb),&end,text,-1,tag);
    gdk_threads_leave();
}
myThread g_thread;
void go_click(GtkWidget* goButton,GtkWidget* noWidget)
{
    //g_print("You click");
    //pthread_t mythread;
    //pthread_create(&mythread,NULL,thread_proc,NULL);
    g_thread.start();
}
int main(int argc,char* argv[])
{
    GtkWidget* window;
    
    g_thread_init(NULL);
    gdk_threads_init();
    gdk_threads_enter();    
    gtk_init(&argc,&argv);
    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
    GtkWidget* vbox = gtk_vbox_new(FALSE,2);
    gtk_container_add(GTK_CONTAINER(window),vbox);
    
    tv = gtk_text_view_new();
    gtk_box_pack_start(GTK_BOX(vbox),tv,TRUE,TRUE,0);
    gtk_widget_set_size_request(tv,160,160);
    GtkWidget* go = gtk_button_new_with_label("go");
    gtk_box_pack_start(GTK_BOX(vbox),go,TRUE,TRUE,0);
    g_signal_connect (G_OBJECT (go),"clicked",G_CALLBACK (go_click),NULL);    
    //write a text to the text view
    GtkTextBuffer* tb = gtk_text_view_get_buffer(GTK_TEXT_VIEW(tv));
    tag = gtk_text_buffer_create_tag (tb, "PASSTAG","scale",PANGO_SCALE_XX_LARGE,NULL);
    GtkTextIter end;
    gtk_text_buffer_get_end_iter(GTK_TEXT_BUFFER(tb),&end);
    gchar text[] = "just a test\n";
    gtk_text_buffer_insert_with_tags(GTK_TEXT_BUFFER(tb),&end,text,-1,tag);
    
    gtk_widget_show_all(window);
    gtk_main();
    gdk_threads_leave();
    return 1;
}
    

Makefile:


CC = g++
RM = rm
GTK_CFLAGS = `pkg-config --cflags gtk+-2.0 gthread-2.0 `
GTK_LIBS = `pkg-config --libs --cflags gtk+-2.0 gthread-2.0 `
CFLAGS = -g -Wall
LIBS = -lpthread
.SUFFIXES:.cpp
SRCS = textview.cpp 
#thread.cpp 
OBJS = $(SRCS:.cpp=.o)
.cpp.o:
 $(CC) $(CFLAGS) $(GTK_CFLAGS) -c $<
tv: $(OBJS)
 $(CC) $(GTK_LIBS) $(LIBS) -o $@ $(OBJS)
clean:
 $(RM) *.o
 $(RM) tv