diff options
Diffstat (limited to 'src/libFLAC/bitreader.c')
| -rw-r--r-- | src/libFLAC/bitreader.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/src/libFLAC/bitreader.c b/src/libFLAC/bitreader.c index aec255bf..1b6e63f6 100644 --- a/src/libFLAC/bitreader.c +++ b/src/libFLAC/bitreader.c @@ -804,6 +804,7 @@ FLAC__bool FLAC__bitreader_read_unary_unsigned(FLAC__BitReader *br, uint32_t *va } #endif +#if 0 /* unused */ FLAC__bool FLAC__bitreader_read_rice_signed(FLAC__BitReader *br, int *val, uint32_t parameter) { FLAC__uint32 lsbs = 0, msbs = 0; @@ -830,6 +831,7 @@ FLAC__bool FLAC__bitreader_read_rice_signed(FLAC__BitReader *br, int *val, uint3 return true; } +#endif /* this is by far the most heavily used reader call. it ain't pretty but it's fast */ FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[], uint32_t nvals, uint32_t parameter) @@ -837,7 +839,7 @@ FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[ /* try and get br->consumed_words and br->consumed_bits into register; * must remember to flush them back to *br before calling other * bitreader functions that use them, and before returning */ - uint32_t cwords, words, lsbs, msbs, x, y; + uint32_t cwords, words, lsbs, msbs, x, y, limit; uint32_t ucbits; /* keep track of the number of unconsumed bits in word */ brword b; int *val, *end; @@ -849,6 +851,8 @@ FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[ FLAC__ASSERT(parameter < 32); /* the above two asserts also guarantee that the binary part never straddles more than 2 words, so we don't have to loop to read it */ + limit = UINT32_MAX >> parameter; /* Maximal msbs that can occur with residual bounded to int32_t */ + val = vals; end = vals + nvals; @@ -857,7 +861,8 @@ FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[ /* read the unary MSBs and end bit */ if(!FLAC__bitreader_read_unary_unsigned(br, &msbs)) return false; - + /* Checking limit here would be overzealous: coding UINT32_MAX + * with parameter == 0 would take 4GiB */ *val++ = (int)(msbs >> 1) ^ -(int)(msbs & 1); } @@ -898,6 +903,9 @@ FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[ ucbits = (ucbits - x - 1) % FLAC__BITS_PER_WORD; msbs = x; + if(x > limit) + return false; + /* read the binary LSBs */ x = (FLAC__uint32)(b >> (FLAC__BITS_PER_WORD - parameter)); /* parameter < 32, so we can cast to 32-bit uint32_t */ if(parameter <= ucbits) { |