1 files changed, 79 insertions, 11 deletions

diff --git a/libavformat/swfdec.c b/libavformat/swfdec.c
index 09770f4f4a..069457f9fd 100644
--- a/libavformat/swfdec.c
+++ b/libavformat/swfdec.c
@@ -3,20 +3,20 @@
  * Copyright (c) 2000 Fabrice Bellard
  * Copyright (c) 2003 Tinic Uro
  *
- * This file is part of Libav.
+ * This file is part of FFmpeg.
  *
- * Libav is free software; you can redistribute it and/or
+ * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * Libav is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with Libav; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -36,8 +36,8 @@ static int get_swf_tag(AVIOContext *pb, int *len_ptr)
 {
     int tag, len;
 
-    if (pb->eof_reached)
-        return -1;
+    if (url_feof(pb))
+        return AVERROR_EOF;
 
     tag = avio_rl16(pb);
     len = tag & 0x3f;
@@ -61,6 +61,39 @@ static int swf_probe(AVProbeData *p)
         return 0;
 }
 
+#if CONFIG_ZLIB
+static int zlib_refill(void *opaque, uint8_t *buf, int buf_size)
+{
+    AVFormatContext *s = opaque;
+    SWFContext *swf = s->priv_data;
+    z_stream *z = &swf->zstream;
+    int ret;
+
+retry:
+    if (!z->avail_in) {
+        int n = avio_read(s->pb, swf->zbuf_in, ZBUF_SIZE);
+        if (n <= 0)
+            return n;
+        z->next_in  = swf->zbuf_in;
+        z->avail_in = n;
+    }
+
+    z->next_out  = buf;
+    z->avail_out = buf_size;
+
+    ret = inflate(z, Z_NO_FLUSH);
+    if (ret < 0)
+        return AVERROR(EINVAL);
+    if (ret == Z_STREAM_END)
+        return AVERROR_EOF;
+
+    if (buf_size - z->avail_out == 0)
+        goto retry;
+
+    return buf_size - z->avail_out;
+}
+#endif
+
 static int swf_read_header(AVFormatContext *s)
 {
     SWFContext *swf = s->priv_data;
@@ -68,14 +101,29 @@ static int swf_read_header(AVFormatContext *s)
     int nbits, len, tag;
 
     tag = avio_rb32(pb) & 0xffffff00;
+    avio_rl32(pb);
 
     if (tag == MKBETAG('C', 'W', 'S', 0)) {
-        av_log(s, AV_LOG_ERROR, "Compressed SWF format not supported\n");
+        av_log(s, AV_LOG_INFO, "SWF compressed file detected\n");
+#if CONFIG_ZLIB
+        swf->zbuf_in  = av_malloc(ZBUF_SIZE);
+        swf->zbuf_out = av_malloc(ZBUF_SIZE);
+        swf->zpb = avio_alloc_context(swf->zbuf_out, ZBUF_SIZE, 0, s,
+                                      zlib_refill, NULL, NULL);
+        if (!swf->zbuf_in || !swf->zbuf_out || !swf->zpb)
+            return AVERROR(ENOMEM);
+        swf->zpb->seekable = 0;
+        if (inflateInit(&swf->zstream) != Z_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to init zlib context\n");
+            return AVERROR(EINVAL);
+        }
+        pb = swf->zpb;
+#else
+        av_log(s, AV_LOG_ERROR, "zlib support is required to read SWF compressed files\n");
         return AVERROR(EIO);
-    }
-    if (tag != MKBETAG('F', 'W', 'S', 0))
+#endif
+    } else if (tag != MKBETAG('F', 'W', 'S', 0))
         return AVERROR(EIO);
-    avio_rl32(pb);
     /* skip rectangle size */
     nbits = avio_r8(pb) >> 3;
     len = (4 * nbits - 3 + 7) / 8;
@@ -95,11 +143,16 @@ static int swf_read_packet(AVFormatContext *s, AVPacket *pkt)
     AVStream *vst = NULL, *ast = NULL, *st = 0;
     int tag, len, i, frame, v, res;
 
+#if CONFIG_ZLIB
+    if (swf->zpb)
+        pb = swf->zpb;
+#endif
+
     for(;;) {
         uint64_t pos = avio_tell(pb);
         tag = get_swf_tag(pb, &len);
         if (tag < 0)
-            return AVERROR(EIO);
+            return tag;
         if (tag == TAG_VIDEOSTREAM) {
             int ch_id = avio_rl16(pb);
             len -= 2;
@@ -218,6 +271,18 @@ static int swf_read_packet(AVFormatContext *s, AVPacket *pkt)
     }
 }
 
+#if CONFIG_ZLIB
+static av_cold int swf_read_close(AVFormatContext *avctx)
+{
+    SWFContext *s = avctx->priv_data;
+    inflateEnd(&s->zstream);
+    av_freep(&s->zbuf_in);
+    av_freep(&s->zbuf_out);
+    av_freep(&s->zpb);
+    return 0;
+}
+#endif
+
 AVInputFormat ff_swf_demuxer = {
     .name           = "swf",
     .long_name      = NULL_IF_CONFIG_SMALL("SWF (ShockWave Flash)"),
@@ -225,4 +290,7 @@ AVInputFormat ff_swf_demuxer = {
     .read_probe     = swf_probe,
     .read_header    = swf_read_header,
     .read_packet    = swf_read_packet,
+#if CONFIG_ZLIB
+    .read_close     = swf_read_close,
+#endif
 };