int ff_amf_read_number(GetByteContext *bc, double *val)
{
uint64_t read;
if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NUMBER)
return AVERROR_INVALIDDATA;
read = bytestream2_get_be64(bc);
*val = av_int2double(read);
return 0;
}
/*
* To be a valid APNG file, we mandate, in this order:
* PNGSIG
* IHDR
* ...
* acTL
* ...
* IDAT
*/
static int apng_probe(AVProbeData *p)
{
GetByteContext gb;
int state = 0;
uint32_t len, tag;
bytestream2_init(&gb, p->buf, p->buf_size);
if (bytestream2_get_be64(&gb) != PNGSIG)
return 0;
for (;;) {
len = bytestream2_get_be32(&gb);
if (len > 0x7fffffff)
return 0;
tag = bytestream2_get_le32(&gb);
/* we don't check IDAT size, as this is the last tag
* we check, and it may be larger than the probe buffer */
if (tag != MKTAG('I', 'D', 'A', 'T') &&
len > bytestream2_get_bytes_left(&gb))
return 0;
switch (tag) {
case MKTAG('I', 'H', 'D', 'R'):
if (len != 13)
return 0;
if (av_image_check_size(bytestream2_get_be32(&gb), bytestream2_get_be32(&gb), 0, NULL))
return 0;
bytestream2_skip(&gb, 9);
state++;
break;
case MKTAG('a', 'c', 'T', 'L'):
if (state != 1 ||
len != 8 ||
bytestream2_get_be32(&gb) == 0) /* 0 is not a valid value for number of frames */
return 0;
bytestream2_skip(&gb, 8);
state++;
break;
case MKTAG('I', 'D', 'A', 'T'):
if (state != 2)
return 0;
goto end;
default:
/* skip other tags */
bytestream2_skip(&gb, len + 4);
break;
}
}
end:
return AVPROBE_SCORE_MAX;
}