[FFmpeg-devel] [PATCH 6/7] avfilter/graphparser: Avoid check whose result is known in advance

Andreas Rheinhardt andreas.rheinhardt at gmail.com
Sun Aug 23 12:50:38 EEST 2020


The result of the last check in code like

if (p)
    foo
else
    p = av_mallocz(sizeof(*p));

if (p->ptr)
    bar
else
    bar2

is known in advance if the else branch of the first check was taken
because av_mallocz() returns zeroed buffers. Therefore the above snippet
can be simplified by moving the check and bar into the foo block.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
---
 libavfilter/graphparser.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/libavfilter/graphparser.c b/libavfilter/graphparser.c
index a52916a146..f55737f8c7 100644
--- a/libavfilter/graphparser.c
+++ b/libavfilter/graphparser.c
@@ -266,20 +266,20 @@ static int link_filter_inouts(AVFilterContext *filt_ctx,
         if (p) {
             *curr_inputs = (*curr_inputs)->next;
             p->next = NULL;
+            if (p->filter_ctx) {
+                ret = link_filter(p->filter_ctx, p->pad_idx, filt_ctx, pad, log_ctx);
+                av_freep(&p->name);
+                av_freep(&p);
+                if (ret < 0)
+                    return ret;
+                continue;
+            }
         } else if (!(p = av_mallocz(sizeof(*p))))
             return AVERROR(ENOMEM);
 
-        if (p->filter_ctx) {
-            ret = link_filter(p->filter_ctx, p->pad_idx, filt_ctx, pad, log_ctx);
-            av_freep(&p->name);
-            av_freep(&p);
-            if (ret < 0)
-                return ret;
-        } else {
-            p->filter_ctx = filt_ctx;
-            p->pad_idx = pad;
-            append_inout(open_inputs, &p);
-        }
+        p->filter_ctx = filt_ctx;
+        p->pad_idx = pad;
+        append_inout(open_inputs, &p);
     }
 
     if (*curr_inputs) {
-- 
2.20.1



More information about the ffmpeg-devel mailing list