From b0b77b9ca572ed95bf24c222931f5f3da8982b89 Mon Sep 17 00:00:00 2001 From: Justin Ruggles Date: Sun, 8 Jul 2012 19:33:10 -0400 Subject: caf: support either old or new style ALAC magic kuki chunk --- libavformat/cafdec.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) (limited to 'libavformat/cafdec.c') diff --git a/libavformat/cafdec.c b/libavformat/cafdec.c index d5ee9be92a..4a04cb0b05 100644 --- a/libavformat/cafdec.c +++ b/libavformat/cafdec.c @@ -121,18 +121,40 @@ static int read_kuki_chunk(AVFormatContext *s, int64_t size) } else if (st->codec->codec_id == CODEC_ID_ALAC) { #define ALAC_PREAMBLE 12 #define ALAC_HEADER 36 - if (size < ALAC_PREAMBLE + ALAC_HEADER) { +#define ALAC_NEW_KUKI 24 + uint8_t preamble[12]; + if (size < ALAC_NEW_KUKI || size > ALAC_PREAMBLE + ALAC_HEADER) { av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n"); avio_skip(pb, size); return AVERROR_INVALIDDATA; } - avio_skip(pb, ALAC_PREAMBLE); + avio_read(pb, preamble, ALAC_PREAMBLE); + st->codec->extradata = av_mallocz(ALAC_HEADER + FF_INPUT_BUFFER_PADDING_SIZE); if (!st->codec->extradata) return AVERROR(ENOMEM); - avio_read(pb, st->codec->extradata, ALAC_HEADER); + + /* For the old style cookie, we skip 12 bytes, then read 36 bytes. + * The new style cookie only contains the last 24 bytes of what was + * 36 bytes in the old style cookie, so we fabricate the first 12 bytes + * in that case to maintain compatibility. */ + if (!memcmp(&preamble[4], "frmaalac", 8)) { + if (size < ALAC_PREAMBLE + ALAC_HEADER) { + av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n"); + av_freep(&st->codec->extradata); + return AVERROR_INVALIDDATA; + } + avio_read(pb, st->codec->extradata, ALAC_HEADER); + avio_skip(pb, size - ALAC_PREAMBLE - ALAC_HEADER); + } else { + AV_WB32(st->codec->extradata, 36); + memcpy(&st->codec->extradata[4], "alac", 4); + AV_WB32(&st->codec->extradata[8], 0); + memcpy(&st->codec->extradata[12], preamble, 12); + avio_read(pb, &st->codec->extradata[24], ALAC_NEW_KUKI - 12); + avio_skip(pb, size - ALAC_NEW_KUKI); + } st->codec->extradata_size = ALAC_HEADER; - avio_skip(pb, size - ALAC_PREAMBLE - ALAC_HEADER); } else { st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE); if (!st->codec->extradata) -- cgit v1.2.3