Revert "apngdec: use side data to pass extradata to the decoder"

This reverts commit e0c6b32046f4bab7d34be77dd2f03b2a80c86d39.

Said commit changed the behavior of the demuxer and decoder in a non
backwards compatible way.
Demuxers should make extradata available at init if possible, and send
new extradata as side data within a packet if needed.

A better fix for the remuxing crash will follow.

Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 2 insertions, 21 deletions

diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 83eeb8d322..36275ae43f 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -45,9 +45,6 @@ typedef struct PNGDecContext {
     ThreadFrame last_picture;
     ThreadFrame picture;
 
-    uint8_t* extra_data;
-    int extra_data_size;
-
     int state;
     int width, height;
     int cur_w, cur_h;
@@ -1364,28 +1361,14 @@ static int decode_frame_apng(AVCodecContext *avctx,
     p = s->picture.f;
 
     if (!(s->state & PNG_IHDR)) {
-        int side_data_size = 0;
-        uint8_t *side_data = NULL;
-        if (avpkt)
-            side_data = av_packet_get_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA, &side_data_size);
-
-        if (side_data_size) {
-            av_freep(&s->extra_data);
-            s->extra_data = av_mallocz(side_data_size + AV_INPUT_BUFFER_PADDING_SIZE);
-            if (!s->extra_data)
-                return AVERROR(ENOMEM);
-            s->extra_data_size = side_data_size;
-            memcpy(s->extra_data, side_data, s->extra_data_size);
-        }
-
-        if (!s->extra_data_size)
+        if (!avctx->extradata_size)
             return AVERROR_INVALIDDATA;
 
         /* only init fields, there is no zlib use in extradata */
         s->zstream.zalloc = ff_png_zalloc;
         s->zstream.zfree  = ff_png_zfree;
 
-        bytestream2_init(&s->gb, s->extra_data, s->extra_data_size);
+        bytestream2_init(&s->gb, avctx->extradata, avctx->extradata_size);
         if ((ret = decode_frame_common(avctx, s, p, avpkt)) < 0)
             goto end;
     }
@@ -1511,8 +1494,6 @@ static av_cold int png_dec_end(AVCodecContext *avctx)
     s->last_row_size = 0;
     av_freep(&s->tmp_row);
     s->tmp_row_size = 0;
-    av_freep(&s->extra_data);
-    s->extra_data_size = 0;
 
     return 0;
 }