diff options
Diffstat (limited to 'src/liblzma/lzma')
| -rw-r--r-- | src/liblzma/lzma/lzma_decoder.c | 42 |
1 files changed, 6 insertions, 36 deletions
diff --git a/src/liblzma/lzma/lzma_decoder.c b/src/liblzma/lzma/lzma_decoder.c index 6e2c166d..dda94177 100644 --- a/src/liblzma/lzma/lzma_decoder.c +++ b/src/liblzma/lzma/lzma_decoder.c @@ -151,10 +151,6 @@ struct lzma_coder_s { /// Length of a repeated match. lzma_length_decoder rep_match_len_decoder; - - /// The first five bytes of LZMA compressed data are treated - /// specially. Once they are read, this stays at zero. - size_t init_bytes_left; }; @@ -166,7 +162,7 @@ struct lzma_coder_s { static bool lzma_attribute((pure)) decode_dummy(const lzma_coder *restrict coder, const uint8_t *restrict in, size_t in_pos_local, - const size_t in_size, uint32_t rc_range, uint32_t rc_code, + const size_t in_size, lzma_range_decoder rc, uint32_t state, uint32_t rep0, const uint32_t now_pos) { uint32_t rc_bound; @@ -268,20 +264,11 @@ decode_dummy(const lzma_coder *restrict coder, coder->pos_decoders + offset, direct_bits); } else { - // Decode direct bits assert(pos_slot >= 14); assert(direct_bits >= 6); direct_bits -= ALIGN_BITS; assert(direct_bits >= 2); - do { - rc_normalize(); - rc_range >>= 1; - const uint32_t t - = (rc_code - rc_range) - >> 31; - rc_code -= rc_range & (t - 1); - } while (--direct_bits > 0); - rep0 <<= ALIGN_BITS; + rc_decode_direct_dummy(direct_bits); bittree_reverse_decode_dummy( coder->pos_align_decoder, @@ -342,15 +329,8 @@ decode_real(lzma_coder *restrict coder, const uint8_t *restrict in, // Initialization // //////////////////// - while (coder->init_bytes_left > 0) { - if (*in_pos == in_size) - return false; - - coder->rc.code = (coder->rc.code << 8) | in[*in_pos]; - ++*in_pos; - --coder->init_bytes_left; - } - + if (!rc_read_init(&coder->rc, in, in_pos, in_size)) + return false; /////////////// // Variables // @@ -386,7 +366,7 @@ decode_real(lzma_coder *restrict coder, const uint8_t *restrict in, while (coder->lz.pos < coder->lz.limit && (in_pos_local < in_limit || (has_safe_buffer && decode_dummy( coder, in, in_pos_local, in_size, - rc_range, rc_code, state, rep0, now_pos)))) { + rc, state, rep0, now_pos)))) { ///////////////////// // Actual decoding // @@ -513,20 +493,11 @@ decode_real(lzma_coder *restrict coder, const uint8_t *restrict in, coder->pos_decoders + offset, direct_bits); } else { - // Decode direct bits assert(pos_slot >= 14); assert(direct_bits >= 6); direct_bits -= ALIGN_BITS; assert(direct_bits >= 2); - do { - rc_normalize(); - rc_range >>= 1; - const uint32_t t - = (rc_code - rc_range) - >> 31; - rc_code -= rc_range & (t - 1); - rep0 = (rep0 << 1) | (1 - t); - } while (--direct_bits > 0); + rc_decode_direct(rep0, direct_bits); rep0 <<= ALIGN_BITS; bittree_reverse_decode(rep0, @@ -762,7 +733,6 @@ lzma_lzma_decoder_init(lzma_next_coder *next, lzma_allocator *allocator, next->coder->pos_bits = options->pos_bits; next->coder->pos_mask = (1 << next->coder->pos_bits) - 1; next->coder->now_pos = 0; - next->coder->init_bytes_left = 5; // Range decoder rc_reset(next->coder->rc); |