enable a flexible lifetime

[ffmpeg] / libavfilter / graphparser.c

diff --git a/libavfilter/graphparser.c b/libavfilter/graphparser.c
index 21ed1f27eb4ffb90c08903e35bcf3a9e1b322d49..c4f621b87efb37f2865993b32f05e6750a9cf92b 100644 (file)
--- a/libavfilter/graphparser.c
+++ b/libavfilter/graphparser.c
@@ -30,24 +30,31 @@
 
 #define WHITESPACES " \n\t"
 
+/**
+ * Link two filters together.
+ *
+ * @see avfilter_link()
+ */
 static int link_filter(AVFilterContext *src, int srcpad,
                        AVFilterContext *dst, int dstpad,
                        AVClass *log_ctx)
 {
-    if (avfilter_link(src, srcpad, dst, dstpad)) {
+    int ret;
+    if ((ret = avfilter_link(src, srcpad, dst, dstpad))) {
         av_log(log_ctx, AV_LOG_ERROR,
-               "cannot create the link %s:%d -> %s:%d\n",
+               "Cannot create the link %s:%d -> %s:%d\n",
                src->filter->name, srcpad, dst->filter->name, dstpad);
-        return -1;
+        return ret;
     }
 
     return 0;
 }
 
 /**
- * Parse "[linkname]"
- * @param name a pointer (that need to be free'd after use) to the name between
- *        parenthesis
+ * Parse the name of a link, which has the format "[linkname]".
+ *
+ * @return a pointer (that need to be freed after use) to the name
+ * between parenthesis
  */
 static char *parse_link_name(const char **buf, AVClass *log_ctx)
 {
@@ -73,6 +80,17 @@ static char *parse_link_name(const char **buf, AVClass *log_ctx)
     return name;
 }
 
+/**
+ * Create an instance of a filter, initialize and insert it in the
+ * filtergraph in *ctx.
+ *
+ * @param ctx the filtergraph context
+ * @param index an index which is supposed to be unique for each filter instance added to the filtergraph
+ * @param filt_name the name of the filter to create
+ * @param args the arguments provided to the filter during its initialization
+ * @param log_ctx the log context to use
+ * @return a filter context in case of successful creation and configuration, NULL otherwise.
+ */
 static AVFilterContext *create_filter(AVFilterGraph *ctx, int index,
                                       const char *filt_name, const char *args,
                                       AVClass *log_ctx)
@@ -89,14 +107,14 @@ static AVFilterContext *create_filter(AVFilterGraph *ctx, int index,
 
     if (!filt) {
         av_log(log_ctx, AV_LOG_ERROR,
-               "no such filter: '%s'\n", filt_name);
+               "No such filter: '%s'\n", filt_name);
         return NULL;
     }
 
-    filt_ctx = avfilter_open(filt, inst_name);
+    avfilter_open(&filt_ctx, filt, inst_name);
     if (!filt_ctx) {
         av_log(log_ctx, AV_LOG_ERROR,
-               "error creating filter '%s'\n", filt_name);
+               "Error creating filter '%s'\n", filt_name);
         return NULL;
     }
 
@@ -113,7 +131,7 @@ static AVFilterContext *create_filter(AVFilterGraph *ctx, int index,
 
     if (avfilter_init_filter(filt_ctx, args, NULL)) {
         av_log(log_ctx, AV_LOG_ERROR,
-               "error initializing filter '%s' with args '%s'\n", filt_name, args);
+               "Error initializing filter '%s' with args '%s'\n", filt_name, args);
         return NULL;
     }