[vlc-devel] [PATCH] filter: add a pf_close callback

[Alexandre Janniaux]

Having a pf_close callback associated to the object instead of the
module allows a filter to wrap any other filter transparently.

In particular, this is a central piece in order to expose other
capability kind of filter as a filter_t video filter using a wrapping
filter_t video filter implementation.
---
 include/vlc_filter.h    | 4 ++++
 src/misc/filter.c       | 4 ++++
 src/misc/filter_chain.c | 4 ++++
 3 files changed, 12 insertions(+)

diff --git a/include/vlc_filter.h b/include/vlc_filter.h
index 9574c318d98..3e52988e459 100644
--- a/include/vlc_filter.h
+++ b/include/vlc_filter.h
@@ -153,6 +153,10 @@ struct filter_t
                                const struct vlc_mouse_t *p_new );
     };
 
+    /* Callback triggered when the filter is to be destroyed.
+     * This can be used in place of the module "close" callback. */
+    void (*pf_close)( filter_t * );
+
     /** Private structure for the owner of the filter */
     filter_owner_t      owner;
 };
diff --git a/src/misc/filter.c b/src/misc/filter.c
index e8c1cae82eb..c3f2aa9525c 100644
--- a/src/misc/filter.c
+++ b/src/misc/filter.c
@@ -121,6 +121,7 @@ vlc_blender_t *filter_NewBlend( vlc_object_t *p_this,
     /* The blend module will be loaded when needed with the real
     * input format */
     p_blend->p_module = NULL;
+    p_blend->pf_close = NULL;
 
     return p_blend;
 }
@@ -170,6 +171,9 @@ int filter_Blend( vlc_blender_t *p_blend,
 
 void filter_DeleteBlend( vlc_blender_t *p_blend )
 {
+    if( p_blend->pf_close )
+        p_blend->pf_close( p_blend );
+
     if( p_blend->p_module )
         module_unneed( p_blend, p_blend->p_module );
 
diff --git a/src/misc/filter_chain.c b/src/misc/filter_chain.c
index 7b1a0ff63bf..a37f29e347b 100644
--- a/src/misc/filter_chain.c
+++ b/src/misc/filter_chain.c
@@ -211,6 +211,7 @@ static filter_t *filter_chain_AppendInner( filter_chain_t *chain,
         return NULL;
 
     filter_t *filter = &chained->filter;
+    filter->pf_close = NULL;
 
     const es_format_t *fmt_in;
     vlc_video_context *vctx_in;
@@ -328,6 +329,9 @@ void filter_chain_DeleteFilter( filter_chain_t *chain, filter_t *filter )
         chain->last = chained->prev;
     }
 
+    if( filter->pf_close )
+        filter->pf_close( filter );
+
     module_unneed( filter, filter->p_module );
 
     msg_Dbg( chain->obj, "Filter %p removed from chain", (void *)filter );
-- 
2.27.0