diff options
| -rw-r--r-- | lib/uzlib/lz77.c | 40 |
1 files changed, 9 insertions, 31 deletions
diff --git a/lib/uzlib/lz77.c b/lib/uzlib/lz77.c index 285b4ddf9..1c7a8442c 100644 --- a/lib/uzlib/lz77.c +++ b/lib/uzlib/lz77.c @@ -56,13 +56,6 @@ static size_t uzlib_lz77_search_max_match(struct uzlib_lz77_state *state, const // Compress the given chunk of data. void uzlib_lz77_compress(struct uzlib_lz77_state *state, const uint8_t *src, unsigned len) { - bool use_src_as_history = false; - if (state->hist_buf == NULL) { - use_src_as_history = true; - state->hist_buf = (uint8_t *)src; - state->hist_len = 0; - } - const uint8_t *top = src + len; while (src < top) { // Look for a match in the history window. @@ -77,31 +70,16 @@ void uzlib_lz77_compress(struct uzlib_lz77_state *state, const uint8_t *src, uns zlib_match(&state->outbuf, match_offset, match_len); } - // Advance the history window. - if (use_src_as_history) { - // Use src as the history, so advance it. - state->hist_len += match_len; - if (state->hist_len > state->hist_max) { - state->hist_buf += state->hist_len - state->hist_max; - state->hist_len = state->hist_max; - } - src += match_len; - } else { - // Push the bytes into the history buffer. - size_t mask = state->hist_max - 1; - while (match_len--) { - uint8_t b = *src++; - state->hist_buf[(state->hist_start + state->hist_len) & mask] = b; - if (state->hist_len == state->hist_max) { - state->hist_start = (state->hist_start + 1) & mask; - } else { - ++state->hist_len; - } + // Push the bytes into the history buffer. + size_t mask = state->hist_max - 1; + while (match_len--) { + uint8_t b = *src++; + state->hist_buf[(state->hist_start + state->hist_len) & mask] = b; + if (state->hist_len == state->hist_max) { + state->hist_start = (state->hist_start + 1) & mask; + } else { + ++state->hist_len; } } } - - if (use_src_as_history) { - state->hist_buf = NULL; - } } |