1 files changed, 16 insertions, 9 deletions

diff --git a/libavformat/flacenc.c b/libavformat/flacenc.c
index 1e4042e070..87e93625f2 100644
--- a/libavformat/flacenc.c
+++ b/libavformat/flacenc.c
@@ -2,25 +2,26 @@
  * raw FLAC muxer
  * Copyright (c) 2006-2009 Justin Ruggles
  *
- * 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
  */
 
 #include "libavcodec/flac.h"
 #include "avformat.h"
+#include "avio_internal.h"
 #include "flacenc.h"
 #include "vorbiscomment.h"
 #include "libavcodec/bytestream.h"
@@ -31,17 +32,14 @@ static int flac_write_block_padding(AVIOContext *pb, unsigned int n_padding_byte
 {
     avio_w8(pb, last_block ? 0x81 : 0x01);
     avio_wb24(pb, n_padding_bytes);
-    while (n_padding_bytes > 0) {
-        avio_w8(pb, 0);
-        n_padding_bytes--;
-    }
+    ffio_fill(pb, 0, n_padding_bytes);
     return 0;
 }
 
 static int flac_write_block_comment(AVIOContext *pb, AVDictionary **m,
                                     int last_block, int bitexact)
 {
-    const char *vendor = bitexact ? "Libav" : LIBAVFORMAT_IDENT;
+    const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
     unsigned int len, count;
     uint8_t *p, *p0;
 
@@ -69,6 +67,15 @@ static int flac_write_header(struct AVFormatContext *s)
     int ret;
     AVCodecContext *codec = s->streams[0]->codec;
 
+    if (s->nb_streams > 1) {
+        av_log(s, AV_LOG_ERROR, "only one stream is supported\n");
+        return AVERROR(EINVAL);
+    }
+    if (codec->codec_id != AV_CODEC_ID_FLAC) {
+        av_log(s, AV_LOG_ERROR, "unsupported codec\n");
+        return AVERROR(EINVAL);
+    }
+
     ret = ff_flac_write_header(s->pb, codec, 0);
     if (ret)
         return ret;