avfilter/all: propagate errors of functions from avfilter/formats

Many of the functions from avfilter/formats can return errors, usually AVERROR(ENOMEM).
This propagates the return values.

All of these were found by using av_warn_unused_result, demonstrating its utility.

Tested with FATE. I am least sure of the changes to avfilter/filtergraph,
since I don't know what/how reduce_format is intended to behave and how it should
react to errors.

Fixes: CID 1325680, 1325679, 1325678.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Previous version Reviewed-by: Nicolas George <george@nsup.org>
Previous version Reviewed-by: Clément Bœsch <u@pkh.me>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/libavfilter/drawutils.c b/libavfilter/drawutils.c
index b65d57cfae..91fffd5e06 100644
--- a/libavfilter/drawutils.c
+++ b/libavfilter/drawutils.c
@@ -532,10 +532,12 @@ AVFilterFormats *ff_draw_supported_pixel_formats(unsigned flags)
     enum AVPixelFormat i;
     FFDrawContext draw;
     AVFilterFormats *fmts = NULL;
+    int ret;
 
     for (i = 0; av_pix_fmt_desc_get(i); i++)
-        if (ff_draw_init(&draw, i, flags) >= 0)
-            ff_add_format(&fmts, i);
+        if (ff_draw_init(&draw, i, flags) >= 0 &&
+            (ret = ff_add_format(&fmts, i)) < 0)
+            return NULL;
     return fmts;
 }