Commit af8ff1be authored by Alexander Schrab's avatar Alexander Schrab Committed by Tim-Philipp Müller

queuearray: fix gst_queue_array_drop_element()

https://bugzilla.gnome.org/show_bug.cgi?id=692691

Conflicts:
	libs/gst/base/gstqueuearray.c
parent 0c643e2c
......@@ -212,52 +212,76 @@ gst_queue_array_is_empty (GstQueueArray * array)
gpointer
gst_queue_array_drop_element (GstQueueArray * array, guint idx)
{
int first_item_index, last_item_index;
gpointer element;
if (idx == array->head) {
/* just move the head */
element = array->array[idx];
g_return_val_if_fail (array->length > 0, NULL);
g_return_val_if_fail (idx < array->size, NULL);
first_item_index = array->head;
/* tail points to the first free spot */
last_item_index = (array->tail - 1 + array->size) % array->size;
element = array->array[idx];
/* simple case idx == first item */
if (idx == first_item_index) {
/* move the head plus one */
array->head++;
array->head %= array->size;
array->length--;
return element;
}
if (idx == array->tail - 1) {
/* just move the tail */
element = array->array[idx];
/* simple case idx == last item */
if (idx == last_item_index) {
/* move tail minus one, potentially wrapping */
array->tail = (array->tail - 1 + array->size) % array->size;
array->length--;
return element;
}
/* drop the element #idx... and readjust the array */
if (array->head < array->tail) {
/* Make sure it's within the boundaries */
g_assert (array->head < idx && idx <= array->tail);
element = array->array[idx];
/* ends not wrapped */
/* move head-idx to head+1 */
memcpy (&array->array[array->head + 1],
&array->array[array->head], (idx - array->head) * sizeof (gpointer));
/* non-wrapped case */
if (first_item_index < last_item_index) {
g_assert (first_item_index < idx && idx < last_item_index);
/* move everything beyond idx one step towards zero in array */
memmove (&array->array[idx],
&array->array[idx + 1], (last_item_index - idx) * sizeof (gpointer));
/* tail might wrap, ie if tail == 0 (and last_item_index == size) */
array->tail = (array->tail - 1 + array->size) % array->size;
array->length--;
return element;
}
/* only wrapped cases left */
g_assert (first_item_index > last_item_index);
if (idx < last_item_index) {
/* idx is before last_item_index, move data towards zero */
memmove (&array->array[idx],
&array->array[idx + 1], (last_item_index - idx) * sizeof (gpointer));
/* tail should not wrap in this case! */
g_assert (array->tail > 0);
array->tail--;
} else {
/* ends are wrapped */
if (idx < array->tail) {
element = array->array[idx];
/* move idx-tail backwards one */
memcpy (&array->array[idx - 1],
&array->array[idx], (array->tail - idx) * sizeof (gpointer));
array->tail--;
} else if (idx >= array->head) {
element = array->array[idx];
/* move head-idx forwards one */
memcpy (&array->array[array->head],
&array->array[array->head + 1],
(idx - array->head) * sizeof (gpointer));
array->head++;
} else {
g_assert_not_reached ();
element = NULL;
}
array->length--;
return element;
}
return element;
if (idx > first_item_index) {
element = array->array[idx];
/* idx is after first_item_index, move data to higher indices */
memmove (&array->array[first_item_index + 1],
&array->array[first_item_index],
(idx - first_item_index) * sizeof (gpointer));
array->head++;
/* head should not wrap in this case! */
g_assert (array->head < array->size);
array->length--;
return element;
}
g_return_val_if_reached (NULL);
}
/**
......
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