gmain.c

嵌入式下基于MiniGUI的Web Browser

	  UNLOCK_CONTEXT (context);
	  return FALSE;
	}
    }
  else
    LOCK_CONTEXT (context);
#endif /* G_THREADS_ENABLED */
  
  if (!context->cached_poll_array)
    {
      context->cached_poll_array_size = context->n_poll_records;
      context->cached_poll_array = g_new (GPollFD, context->n_poll_records);
    }

  allocated_nfds = context->cached_poll_array_size;
  fds = context->cached_poll_array;
  
  UNLOCK_CONTEXT (context);

  some_ready = g_main_context_prepare (context, &max_priority); 
  
  while ((nfds = g_main_context_query (context, max_priority, &timeout, fds, 
				       allocated_nfds)) > allocated_nfds)
    {
      LOCK_CONTEXT (context);
      g_free (fds);
      context->cached_poll_array_size = allocated_nfds = nfds;
      context->cached_poll_array = fds = g_new (GPollFD, nfds);
      UNLOCK_CONTEXT (context);
    }

  if (!block)
    timeout = 0;
  
  g_main_context_poll (context, timeout, max_priority, fds, nfds);
  
  g_main_context_check (context, max_priority, fds, nfds);
  
  if (dispatch)
    g_main_context_dispatch (context);
  
#ifdef G_THREADS_ENABLED
  g_main_context_release (context);
#endif /* G_THREADS_ENABLED */    

  LOCK_CONTEXT (context);

  return some_ready;
}

/**
 * g_main_context_pending:
 * @context: a #GMainContext (if %NULL, the default context will be used)
 *
 * Checks if any sources have pending events for the given context.
 * 
 * Return value: %TRUE if events are pending.
 **/
gboolean 
g_main_context_pending (GMainContext *context)
{
  gboolean retval;

  if (!context)
    context = g_main_context_default();

  LOCK_CONTEXT (context);
  retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF);
  UNLOCK_CONTEXT (context);
  
  return retval;
}

/**
 * g_main_context_iteration:
 * @context: a #GMainContext (if %NULL, the default context will be used) 
 * @may_block: whether the call may block.
 * 
 * Runs a single iteration for the given main loop. This involves
 * checking to see if any event sources are ready to be processed,
 * then if no events sources are ready and @may_block is %TRUE, waiting
 * for a source to become ready, then dispatching the highest priority
 * events sources that are ready. Note that even when @may_block is %TRUE,
 * it is still possible for g_main_context_iteration() to return
 * %FALSE, since the the wait may be interrupted for other
 * reasons than an event source becoming ready.
 * 
 * Return value: %TRUE if events were dispatched.
 **/
gboolean
g_main_context_iteration (GMainContext *context, gboolean may_block)
{
  gboolean retval;

  if (!context)
    context = g_main_context_default();
  
  LOCK_CONTEXT (context);
  retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
  UNLOCK_CONTEXT (context);
  
  return retval;
}

/**
 * g_main_loop_new:
 * @context: a #GMainContext  (if %NULL, the default context will be used).
 * @is_running: set to %TRUE to indicate that the loop is running. This
 * is not very important since calling g_main_loop_run() will set this to
 * %TRUE anyway.
 * 
 * Creates a new #GMainLoop structure.
 * 
 * Return value: a new #GMainLoop.
 **/
GMainLoop *
g_main_loop_new (GMainContext *context,
		 gboolean      is_running)
{
  GMainLoop *loop;
  
  if (!context)
    context = g_main_context_default();
  
  g_main_context_ref (context);

  loop = g_new0 (GMainLoop, 1);
  loop->context = context;
  loop->is_running = is_running != FALSE;
  loop->ref_count = 1;
  
  return loop;
}

/**
 * g_main_loop_ref:
 * @loop: a #GMainLoop
 * 
 * Increases the reference count on a #GMainLoop object by one.
 * 
 * Return value: @loop
 **/
GMainLoop *
g_main_loop_ref (GMainLoop *loop)
{
  g_return_val_if_fail (loop != NULL, NULL);
  g_return_val_if_fail (loop->ref_count > 0, NULL);

  LOCK_CONTEXT (loop->context);
  loop->ref_count++;
  UNLOCK_CONTEXT (loop->context);

  return loop;
}

static void
g_main_loop_unref_and_unlock (GMainLoop *loop)
{
  loop->ref_count--;
  if (loop->ref_count == 0)
    {
      /* When the ref_count is 0, there can be nobody else using the
       * loop, so it is safe to unlock before destroying.
       */
      g_main_context_unref_and_unlock (loop->context);
  g_free (loop);
    }
  else
    UNLOCK_CONTEXT (loop->context);
}

/**
 * g_main_loop_unref:
 * @loop: a #GMainLoop
 * 
 * Decreases the reference count on a #GMainLoop object by one. If
 * the result is zero, free the loop and free all associated memory.
 **/
void
g_main_loop_unref (GMainLoop *loop)
{
  g_return_if_fail (loop != NULL);
  g_return_if_fail (loop->ref_count > 0);

  LOCK_CONTEXT (loop->context);
  
  g_main_loop_unref_and_unlock (loop);
}

/**
 * g_main_loop_run:
 * @loop: a #GMainLoop
 * 
 * Runs a main loop until g_main_loop_quit() is called on the loop.
 * If this is called for the thread of the loop's #GMainContext,
 * it will process events from the loop, otherwise it will
 * simply wait.
 **/
void 
g_main_loop_run (GMainLoop *loop)
{
  GThread *self = G_THREAD_SELF;

  g_return_if_fail (loop != NULL);
  g_return_if_fail (loop->ref_count > 0);

#ifdef G_THREADS_ENABLED
  if (!g_main_context_acquire (loop->context))
    {
      gboolean got_ownership = FALSE;
      
      /* Another thread owns this context */
      if (!g_thread_supported ())
	{
	  g_warning ("g_main_loop_run() was called from second thread but "
		     "g_thread_init() was never called.");
	  return;
	}
      
      LOCK_CONTEXT (loop->context);

      loop->ref_count++;

      if (!loop->is_running)
	loop->is_running = TRUE;

      if (!loop->context->cond)
	loop->context->cond = g_cond_new ();
          
      while (loop->is_running || !got_ownership)
	got_ownership = g_main_context_wait (loop->context,
					     loop->context->cond,
					     g_static_mutex_get_mutex (&loop->context->mutex));
      
      if (!loop->is_running)
	{
	  UNLOCK_CONTEXT (loop->context);
	  if (got_ownership)
	    g_main_context_release (loop->context);
	  g_main_loop_unref (loop);
	  return;
	}

      g_assert (got_ownership);
    }
  else
    LOCK_CONTEXT (loop->context);
#endif /* G_THREADS_ENABLED */ 

  if (loop->context->in_check_or_prepare)
    {
      g_warning ("g_main_loop_run(): called recursively from within a source's "
		 "check() or prepare() member, iteration not possible.");
      return;
    }

  loop->ref_count++;
  loop->is_running = TRUE;
  while (loop->is_running)
    g_main_context_iterate (loop->context, TRUE, TRUE, self);

  UNLOCK_CONTEXT (loop->context);
  
#ifdef G_THREADS_ENABLED
  g_main_context_release (loop->context);
#endif /* G_THREADS_ENABLED */    
  
  g_main_loop_unref (loop);
}

/**
 * g_main_loop_quit:
 * @loop: a #GMainLoop
 * 
 * Stops a #GMainLoop from running. Any calls to g_main_loop_run()
 * for the loop will return.
 **/
void 
g_main_loop_quit (GMainLoop *loop)
{
  g_return_if_fail (loop != NULL);
  g_return_if_fail (loop->ref_count > 0);

  LOCK_CONTEXT (loop->context);
  loop->is_running = FALSE;
  g_main_context_wakeup_unlocked (loop->context);

#ifdef G_THREADS_ENABLED
  if (loop->context->cond)
    g_cond_broadcast (loop->context->cond);
#endif /* G_THREADS_ENABLED */

  UNLOCK_CONTEXT (loop->context);
}

/**
 * g_main_loop_is_running:
 * @loop: a #GMainLoop.
 * 
 * Checks to see if the main loop is currently being run via g_main_loop_run().
 * 
 * Return value: %TRUE if the mainloop is currently being run.
 **/
gboolean
g_main_loop_is_running (GMainLoop *loop)
{
  g_return_val_if_fail (loop != NULL, FALSE);
  g_return_val_if_fail (loop->ref_count > 0, FALSE);

  return loop->is_running;
}

/**
 * g_main_loop_get_context:
 * @loop: a #GMainLoop.
 * 
 * Returns the #GMainContext of @loop.
 * 
 * Return value: the #GMainContext of @loop
 **/
GMainContext *
g_main_loop_get_context (GMainLoop *loop)
{
  g_return_val_if_fail (loop != NULL, NULL);
  g_return_val_if_fail (loop->ref_count > 0, NULL);
 
  return loop->context;
}

/* HOLDS: context's lock */
static void
g_main_context_poll (GMainContext *context,
		     gint          timeout,
		     gint          priority,
		     GPollFD      *fds,
		     gint          n_fds)
{
#ifdef  G_MAIN_POLL_DEBUG
  GTimer *poll_timer;
  GPollRec *pollrec;
  gint i;
#endif

  GPollFunc poll_func;

  if (n_fds || timeout != 0)
    {
#ifdef	G_MAIN_POLL_DEBUG
      g_print ("g_main_poll(%d) timeout: %d\n", n_fds, timeout);
      poll_timer = g_timer_new ();
#endif

      LOCK_CONTEXT (context);

      poll_func = context->poll_func;
      
      UNLOCK_CONTEXT (context);
      if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR)
	g_warning ("poll(2) failed due to: %s.",
		   g_strerror (errno));
      
#ifdef	G_MAIN_POLL_DEBUG
      LOCK_CONTEXT (context);

      g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds",
	       n_fds,
	       timeout,
	       g_timer_elapsed (poll_timer, NULL));
      g_timer_destroy (poll_timer);
      pollrec = context->poll_records;
      i = 0;
      while (i < n_fds)
	{
	  if (pollrec->fd->events)
	    {
	      if (fds[i].revents)
		{
		  g_print (" [%d:", fds[i].fd);
		  if (fds[i].revents & G_IO_IN)
		    g_print ("i");
		  if (fds[i].revents & G_IO_OUT)
		    g_print ("o");
		  if (fds[i].revents & G_IO_PRI)
		    g_print ("p");
		  if (fds[i].revents & G_IO_ERR)
		    g_print ("e");
		  if (fds[i].revents & G_IO_HUP)
		    g_print ("h");
		  if (fds[i].revents & G_IO_NVAL)
		    g_print ("n");
		  g_print ("]");
		}
	      i++;
	    }
	  pollrec = pollrec->next;
	}
      g_print ("\n");
      
      UNLOCK_CONTEXT (context);
#endif
    } /* if (n_fds || timeout != 0) */
}

/**
 * g_main_context_add_poll:
 * @context: a #GMainContext (or %NULL for the default context)
 * @fd: a #GPollFD structure holding information about a file
 *      descriptor to watch.
 * @priority: the priority for this file descriptor which should be
 *      the same as the priority used for g_source_attach() to ensure that the
 *      file descriptor is polled whenever the results may be needed.
 * 
 * Adds a file descriptor to the set of file descriptors polled for
 * this context. This will very seldomly be used directly. Instead
 * a typical event source will use g_source_add_poll() instead.
 **/
void
g_main_context_add_poll (GMainContext *context,
			 GPollFD      *fd,
			 gint          priority)
{
  if (!context)
    context = g_main_context_default ();
  
  g_return_if_fail (context->ref_count > 0);
  g_return_if_fail (fd);

  LOCK_CONTEXT (context);
  g_main_context_add_poll_unlocked (context, priority, fd);
  UNLOCK_CONTEXT (context);
}

/* HOLDS: main_loop_lock */
static void 
g_main_context_add_poll_unlocked (GMainContext *context,
				  gint          priority,
				  GPollFD      *fd)
{
  GPollRec *lastrec, *pollrec, *newrec;

  if (!context->poll_chunk)
    context->poll_chunk = g_mem_chunk_create (GPollRec, 32, G_ALLOC_ONLY);

  if (context->poll_free_list)
    {
      newrec = context->poll_free_list;
      context->poll_free_list = newrec->next;
    }
  else
    newrec = g_chunk_new (GPollRec, context->poll_chunk);

  /* This file descriptor may be checked before we ever poll */
  fd->revents = 0;
  newrec->fd = fd;
  newrec->priority = priority;

  lastrec = NULL;
  pollrec = context->poll_records;
  while (pollrec && priority >= pollrec->priority)
    {
      lastrec = pollrec;
      pollrec = pollrec->next;
    }
  
  if (lastrec)
    lastrec->next = newrec;
  else
    context->poll_records = newrec;

  newrec->next = pollrec;

  context->n_poll_records++;

#ifdef G_THREADS_ENABLED
  context->poll_changed = TRUE;

  /* Now wake up the main loop if it is waiting in the poll() */
  g_main_context_wakeup_unlocked (context);
#endif
}

/**
 * g_main_context_remove_poll:
 * @context:a #GMainContext 
 * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll()
 * 
 * Removes file descriptor from the set of file descriptors to be
 * polled for a particular context.
 **/
void
g_main_context_remove_poll (GMainContext *context,
			    GPollFD      *fd)
{
  if (!context)
    context = g_main_context_default ();
  
  g_return_if_fail (context->ref_count > 0);
  g_return_if_fail (fd);

  LOCK_CONTEXT (context);
  g_main_context_remove_poll_unlocked (context, fd);
  UNLOCK_CONTEXT (context);
}

static void
g_main_context_remove_poll_unlocked (GMainContext *context,
				     GPollFD      *fd)
{
  GPollRec *pollrec, *lastrec;

  lastrec = NULL;
  pollrec = context->poll_records;

  while (pollrec)
    {
      if (pollrec->fd == fd)
	{
	  if (lastrec != NULL)
	    lastrec->next = pollrec->next;
	  else
	    context->poll_records = pollrec->next;

#ifdef ENABLE_GC_FRIENDLY
	  pollrec->fd = NULL;  
#endif /* ENABLE_GC_FRIENDLY */

	  pollrec->next = context->poll_free_list;
	  context->poll_free_list = pollrec;

	  context->n_poll_records--;
	  break;
	}
      lastrec = pollrec;
      pollrec = pollrec->next;
    }

#ifdef G_THREADS_ENABLED
  context->poll_changed = TRUE;
  
  /* Now wake up the main loop if it is waiting in the poll() */
  g_main_context_wakeup_unlocked (context);
#endif
}

/**
 * g_source_get_current_time:
 * @source:  a #GSource
 * @timeval: #GTimeVal structure in which to store current time.
 * 
 * Gets the "current time" to be used when checking 
 * this source. The advantage of calling this function over
 * calling g_get_current_time() directly is that when 
 * checking multiple sources, GLib can cache a single value
 * instead of having to repeatedly get the system time.
 **/
void
g_source_get_curr