[vlc-devel] commit: embedded snapshot: use condition variable (Olivier Aubert )
git version control
git at videolan.org
Mon Jan 26 16:58:15 CET 2009
vlc | branch: master | Olivier Aubert <olivier.aubert at liris.cnrs.fr> | Mon Jan 26 16:57:48 2009 +0100| [1fb01424d70e6b99f63d56d5243ef0d6dc458f0d] | committer: Olivier Aubert
embedded snapshot: use condition variable
Let's see if this fits courmisch's standards...
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=1fb01424d70e6b99f63d56d5243ef0d6dc458f0d
---
include/vlc_vout.h | 2 +
src/control/mediacontrol_audio_video.c | 57 ++++++++++++++++++++++++--------
src/video_output/vout_intf.c | 34 +++++--------------
3 files changed, 54 insertions(+), 39 deletions(-)
diff --git a/include/vlc_vout.h b/include/vlc_vout.h
index e0d3ecb..adab0a6 100644
--- a/include/vlc_vout.h
+++ b/include/vlc_vout.h
@@ -714,6 +714,8 @@ typedef struct snapshot_t {
int i_height; /* In pixels */
int i_datasize; /* In bytes */
mtime_t date; /* Presentation time */
+ vlc_cond_t p_condvar;
+ vlc_mutex_t p_mutex;
} snapshot_t;
/**@}*/
diff --git a/src/control/mediacontrol_audio_video.c b/src/control/mediacontrol_audio_video.c
index f2367de..1766034 100644
--- a/src/control/mediacontrol_audio_video.c
+++ b/src/control/mediacontrol_audio_video.c
@@ -56,7 +56,6 @@ mediacontrol_snapshot( mediacontrol_Instance *self,
mediacontrol_Exception *exception )
{
(void)a_position;
- vlc_object_t* p_cache;
vout_thread_t* p_vout;
input_thread_t *p_input;
mediacontrol_RGBPicture *p_pic = NULL;
@@ -67,6 +66,13 @@ mediacontrol_snapshot( mediacontrol_Instance *self,
libvlc_exception_init( &ex );
mediacontrol_exception_init( exception );
+
+ p_snapshot = malloc( sizeof( snapshot_t ) );
+ if( ! p_snapshot )
+ {
+ RAISE_NULL( mediacontrol_InternalException, "Cannot allocate snapshot" );
+ }
+
p_input = libvlc_get_input_thread( self->p_media_player, &ex );
if( ! p_input )
{
@@ -79,26 +85,49 @@ mediacontrol_snapshot( mediacontrol_Instance *self,
{
RAISE_NULL( mediacontrol_InternalException, "No video output" );
}
- p_cache = vlc_object_create( p_input, sizeof( vlc_object_t ) );
- if( p_cache == NULL )
- {
- vlc_object_release( p_vout );
- vlc_object_release( p_input );
- RAISE_NULL( mediacontrol_InternalException, "Out of memory" );
- }
- snprintf( path, 255, "object:%p", p_cache );
+
+ /* TODO:
+ vlc_mutex_lock (&lock);
+ mutex_cleanup_push (&lock); // release the mutex in case of cancellation
+
+ while (!foobar)
+ vlc_cond_wait (&wait, &lock);
+
+ --- foobar is now true, do something about it here --
+
+ vlc_cleanup_run (); // release the mutex
+ */
+
+ snprintf( path, 255, "object:%p", p_snapshot );
var_SetString( p_vout, "snapshot-path", path );
var_SetString( p_vout, "snapshot-format", "png" );
- vlc_object_lock( p_cache );
+ vlc_mutex_init( &p_snapshot->p_mutex );
+ vlc_cond_init( &p_snapshot->p_condvar );
+
+ vlc_mutex_lock( &p_snapshot->p_mutex );
+ mutex_cleanup_push( &p_snapshot->p_mutex );
+
+ /* Use p_snapshot address as sentinel against spurious vlc_object_wait wakeups.
+
+ If a legitimate wakeup occurs, then p_snapshot->p_data will hold either
+ NULL (in case of error) or a pointer to valid data. */
+ p_snapshot->p_data = ( char* )p_snapshot;
+
vout_Control( p_vout, VOUT_SNAPSHOT );
+ while ( p_snapshot->p_data == ( char* )p_snapshot )
+ {
+ vlc_cond_wait( &p_snapshot->p_condvar, &p_snapshot->p_mutex );
+ }
+ vlc_cleanup_pop();
+
vlc_object_release( p_vout );
- p_snapshot = ( snapshot_t* ) p_cache->p_private;
- vlc_object_unlock( p_cache );
- vlc_object_release( p_cache );
+ vlc_mutex_unlock( &p_snapshot->p_mutex );
+ vlc_cond_destroy( &p_snapshot->p_condvar );
+ vlc_mutex_destroy( &p_snapshot->p_mutex );
- if( p_snapshot )
+ if( p_snapshot->p_data )
{
/* Note: p_snapshot->p_data is directly used, not copied. Thus
do not free it here. */
diff --git a/src/video_output/vout_intf.c b/src/video_output/vout_intf.c
index 0f837ff..dccbc7e 100644
--- a/src/video_output/vout_intf.c
+++ b/src/video_output/vout_intf.c
@@ -638,13 +638,12 @@ int vout_Snapshot( vout_thread_t *p_vout, picture_t *p_pic )
*/
if( b_embedded_snapshot )
{
- vlc_object_t* p_dest = p_obj;
block_t *p_block;
- snapshot_t *p_snapshot;
+ snapshot_t *p_snapshot = p_obj;
size_t i_size;
- vlc_object_lock( p_dest );
- p_dest->p_private = NULL;
+ vlc_mutex_lock( &p_snapshot->p_mutex );
+ p_snapshot->p_data = NULL;
/* Save the snapshot to a memory zone */
p_block = image_Write( p_image, p_pic, &fmt_in, &fmt_out );
@@ -652,23 +651,11 @@ int vout_Snapshot( vout_thread_t *p_vout, picture_t *p_pic )
{
msg_Err( p_vout, "Could not get snapshot" );
image_HandlerDelete( p_image );
- vlc_object_signal_unlocked( p_dest );
- vlc_object_unlock( p_dest );
+ vlc_cond_signal( &p_snapshot->p_condvar );
+ vlc_mutex_unlock( &p_snapshot->p_mutex );
return VLC_EGENERIC;
}
- /* Copy the p_block data to a snapshot structure */
- /* FIXME: get the timestamp */
- p_snapshot = malloc( sizeof( snapshot_t ) );
- if( !p_snapshot )
- {
- block_Release( p_block );
- image_HandlerDelete( p_image );
- vlc_object_signal_unlocked( p_dest );
- vlc_object_unlock( p_dest );
- return VLC_ENOMEM;
- }
-
i_size = p_block->i_buffer;
p_snapshot->i_width = fmt_out.i_width;
@@ -679,21 +666,18 @@ int vout_Snapshot( vout_thread_t *p_vout, picture_t *p_pic )
if( !p_snapshot->p_data )
{
block_Release( p_block );
- free( p_snapshot );
image_HandlerDelete( p_image );
- vlc_object_signal_unlocked( p_dest );
- vlc_object_unlock( p_dest );
+ vlc_cond_signal( &p_snapshot->p_condvar );
+ vlc_mutex_unlock( &p_snapshot->p_mutex );
return VLC_ENOMEM;
}
memcpy( p_snapshot->p_data, p_block->p_buffer, p_block->i_buffer );
- p_dest->p_private = p_snapshot;
-
block_Release( p_block );
/* Unlock the object */
- vlc_object_signal_unlocked( p_dest );
- vlc_object_unlock( p_dest );
+ vlc_cond_signal( &p_snapshot->p_condvar );
+ vlc_mutex_unlock( &p_snapshot->p_mutex );
image_HandlerDelete( p_image );
return VLC_SUCCESS;
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