From 3555d2e88e2ad11c6368074469b8881c50934cb9 Mon Sep 17 00:00:00 2001
From: Stefano Sabatini <stefano.sabatini-lala@poste.it>
Date: Tue, 27 Oct 2009 19:52:14 +0000
Subject: [PATCH] Introduce first_avfilter and use that, together with
 AVFilter.next, for registering and finding filters, rather than use the
 struct AVFilterList, which is removed.

Simplify the filter registration management code.

Originally committed as revision 20387 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavfilter/avfilter.c | 34 +++++++++++++---------------------
 1 file changed, 13 insertions(+), 21 deletions(-)

diff --git a/libavfilter/avfilter.c b/libavfilter/avfilter.c
index bc49bd6..5e33047 100644
--- a/libavfilter/avfilter.c
+++ b/libavfilter/avfilter.c
@@ -28,13 +28,6 @@ unsigned avfilter_version(void) {
     return LIBAVFILTER_VERSION_INT;
 }
 
-/** list of registered filters */
-static struct FilterList
-{
-    AVFilter *filter;
-    struct FilterList *next;
-} *filters = NULL;
-
 /** helper macros to get the in/out pad on the dst/src filter */
 #define link_dpad(link)     link->dst-> input_pads[link->dstpad]
 #define link_spad(link)     link->src->output_pads[link->srcpad]
@@ -327,34 +320,33 @@ void avfilter_draw_slice(AVFilterLink *link, int y, int h)
     draw_slice(link, y, h);
 }
 
+AVFilter *first_avfilter = NULL;
+
 AVFilter *avfilter_get_by_name(const char *name)
 {
-    struct FilterList *filt;
+    AVFilter *filter;
 
-    for(filt = filters; filt; filt = filt->next)
-        if(!strcmp(filt->filter->name, name))
-            return filt->filter;
+    for (filter = first_avfilter; filter; filter = filter->next)
+        if (!strcmp(filter->name, name))
+            return filter;
 
     return NULL;
 }
 
 void avfilter_register(AVFilter *filter)
 {
-    struct FilterList *newfilt = av_malloc(sizeof(struct FilterList));
+    AVFilter **p;
+    p = &first_avfilter;
+    while (*p)
+        p = &(*p)->next;
 
-    newfilt->filter = filter;
-    newfilt->next   = filters;
-    filters         = newfilt;
+    *p = filter;
+    filter->next = NULL;
 }
 
 void avfilter_uninit(void)
 {
-    struct FilterList *tmp;
-
-    for(; filters; filters = tmp) {
-        tmp = filters->next;
-        av_free(filters);
-    }
+    first_avfilter = NULL;
 }
 
 static int pad_count(const AVFilterPad *pads)
-- 
2.7.4