lavf: simplify handling of offset in av_probe_input_buffer()

(cherry picked from commit c1868e7ee7)

Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
Anton Khirnov
2014-01-13 11:55:18 +01:00
parent 9aa22918c2
commit e38c62fe0c

View File

@@ -357,7 +357,7 @@ int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
const char *filename, void *logctx,
unsigned int offset, unsigned int max_probe_size)
{
AVProbeData pd = { filename ? filename : "", NULL, -offset };
AVProbeData pd = { filename ? filename : "" };
unsigned char *buf = NULL;
int ret = 0, probe_size;
@@ -372,16 +372,14 @@ int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
if (offset >= max_probe_size) {
return AVERROR(EINVAL);
}
avio_skip(pb, offset);
max_probe_size -= offset;
for(probe_size= PROBE_BUF_MIN; probe_size<=max_probe_size && !*fmt;
probe_size = FFMIN(probe_size<<1, FFMAX(max_probe_size, probe_size+1))) {
int score = probe_size < max_probe_size ? AVPROBE_SCORE_MAX/4 : 0;
int buf_offset = (probe_size == PROBE_BUF_MIN) ? 0 : probe_size>>1;
if (probe_size < offset) {
continue;
}
/* read probe data */
buf = av_realloc(buf, probe_size + AVPROBE_PADDING_SIZE);
if ((ret = avio_read(pb, buf + buf_offset, probe_size - buf_offset)) < 0) {
@@ -394,7 +392,7 @@ int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
ret = 0; /* error was end of file, nothing read */
}
pd.buf_size += ret;
pd.buf = &buf[offset];
pd.buf = buf;
memset(pd.buf + pd.buf_size, 0, AVPROBE_PADDING_SIZE);