/** Safe cast from wl_output
*
* \param wo The wl_output to cast from.
* \return The corresponding struct output, or NULL.
*
* This is safe to call with NULL. The returned pointer is non-NULL only
* if the wl_output really has a struct output associated.
*/
struct output *
output_from_wl_output(struct wl_output *wo)
{
const void *impl;
if (!wo)
return NULL;
impl = wl_proxy_get_listener((struct wl_proxy *)wo);
if (impl != &output_listener)
return NULL;
return wl_output_get_user_data(wo);
}
int shm_buffer_resize(shm_buffer_t *buffer, uint32_t width, uint32_t height)
{
uint32_t new_stride = SHM_BUFFER_STRIDE(width, buffer->bytes);
uint32_t new_size = new_stride * height;
if (SHM_BUFFER_IS_BUSY(buffer)) {
SHM_BUFFER_SET_PNDNG_RSZ(buffer);
buffer->pending_width = width;
buffer->pending_height = height;
return SHM_BUFFER_BUSY;
}
SHM_BUFFER_CLEAR_PNDNG_RSZ(buffer);
if (new_size > buffer->pool_size) {
munmap(buffer->data, buffer->pool_size);
ftruncate(buffer->fd, new_size);
buffer->data = mmap(NULL, new_size, PROT_READ | PROT_WRITE,
MAP_SHARED, buffer->fd, 0);
// TODO: the buffer should be destroyed when -1 is return
if (buffer->data == MAP_FAILED)
return -1;
wl_shm_pool_resize(buffer->shm_pool, new_size);
buffer->pool_size = new_size;
}
const void *listener = wl_proxy_get_listener((struct wl_proxy*)buffer->buffer);
wl_buffer_destroy(buffer->buffer);
buffer->buffer = wl_shm_pool_create_buffer(buffer->shm_pool,
0, width, height, new_stride,
buffer->format.wl_format);
wl_buffer_add_listener(buffer->buffer, listener, buffer);
buffer->height = height;
buffer->stride = new_stride;
return 0;
}
