[FFmpeg-cvslog] avcodec/pngdec: Use internal AVBPrint string when parsing chunks

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Wed Mar 17 15:20:45 2021 +0100| [3d4a5ef5c198b844cd38be7366957d3ea2354792] | committer: Andreas Rheinhardt

avcodec/pngdec: Use internal AVBPrint string when parsing chunks

One saves an allocation in case the string fits into the buffer.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3d4a5ef5c198b844cd38be7366957d3ea2354792
---

 libavcodec/pngdec.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 8a197d038d..189c3eee89 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -543,10 +543,8 @@ static int decode_text_chunk(PNGDecContext *s, GetByteContext *gb, int compresse
             return AVERROR_INVALIDDATA;
         if ((ret = decode_zbuf(&bp, data, data_end, s->avctx)) < 0)
             return ret;
+        text     = bp.str;
         text_len = bp.len;
-        ret = av_bprint_finalize(&bp, (char **)&text);
-        if (ret < 0)
-            return ret;
     } else {
         text = (uint8_t *)data;
         text_len = data_end - text;
@@ -554,8 +552,8 @@ static int decode_text_chunk(PNGDecContext *s, GetByteContext *gb, int compresse
 
     kw_utf8  = iso88591_to_utf8(keyword, keyword_end - keyword);
     txt_utf8 = iso88591_to_utf8(text, text_len);
-    if (text != data)
-        av_free(text);
+    if (compressed)
+        av_bprint_finalize(&bp, NULL);
     if (!(kw_utf8 && txt_utf8)) {
         av_free(kw_utf8);
         av_free(txt_utf8);