avfilter/formats: Make ff_formats_pixdesc_filter return AVFilterFormats*

Up until now, it has returned the AVFilterFormats list via
an AVFilterFormats** parameter; the actual return value was an int
that was always AVERROR(ENOMEM) on error. The AVFilterFormats**
argument was a pure output parameter which was only documented
by naming the parameter rfmts. Yet nevertheless all callers
initialized the underlying AVFilterFormats* to NULL.

This commit changes this to return a pointer to AVFilterFormats
directly. This is more in line with the API in general, as it
allows to avoid checks for intermediate values.

Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

1 files changed, 4 insertions, 9 deletions

diff --git a/libavfilter/vf_fieldhint.c b/libavfilter/vf_fieldhint.c
index c6c2a8eebe..c41f2ef751 100644
--- a/libavfilter/vf_fieldhint.c
+++ b/libavfilter/vf_fieldhint.c
@@ -77,16 +77,11 @@ static av_cold int init(AVFilterContext *ctx)
 
 static int query_formats(AVFilterContext *ctx)
 {
-    AVFilterFormats *formats = NULL;
-    int ret;
+    int reject_flags = AV_PIX_FMT_FLAG_BITSTREAM |
+                       AV_PIX_FMT_FLAG_HWACCEL   |
+                       AV_PIX_FMT_FLAG_PAL;
 
-    ret = ff_formats_pixdesc_filter(&formats, 0,
-                                    AV_PIX_FMT_FLAG_HWACCEL |
-                                    AV_PIX_FMT_FLAG_BITSTREAM |
-                                    AV_PIX_FMT_FLAG_PAL);
-    if (ret < 0)
-        return ret;
-    return ff_set_common_formats(ctx, formats);
+    return ff_set_common_formats(ctx, ff_formats_pixdesc_filter(0, reject_flags));
 }
 
 static int config_input(AVFilterLink *inlink)