X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=deflate.c;h=f0f23940ac9d0c891877105ebc803d508483987d;hb=b6def44c57e9b31b98b7766c8916531a4db9fd27;hp=bb8a749ac5a08dabd589cbd999f9b2a3f6dddfba;hpb=5382c729b658e85774b293c00fd600cae1d3937e;p=debian%2Fgzip diff --git a/deflate.c b/deflate.c index bb8a749..f0f2394 100644 --- a/deflate.c +++ b/deflate.c @@ -131,14 +131,6 @@ #endif /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ -#ifndef RSYNC_WIN -# define RSYNC_WIN 8192 -#endif -/* Size of rsync window, must be < MAX_DIST */ - -#define RSYNC_SUM_MATCH(sum) (((sum) & (RSYNC_WIN - 1)) == 0) -/* Whether window sum matches magic value */ - /* =========================================================================== * Local data used by the "longest match" routines. */ @@ -220,8 +212,6 @@ local int compr_level; unsigned good_match; /* Use a faster search when the previous match is longer than this */ -local ulg rsync_sum; /* rolling sum of rsync window */ -local ulg rsync_chunk_end; /* next rsync sequence point */ /* Values for max_lazy_match, good_match and max_chain_length, depending on * the desired pack level (0..9). The values given below have been tuned to @@ -324,10 +314,6 @@ void lm_init (pack_level, flags) #endif /* prev will be initialized on the fly */ - /* rsync params */ - rsync_chunk_end = 0xFFFFFFFFUL; - rsync_sum = 0; - /* Set the default configuration parameters: */ max_lazy_match = configuration_table[pack_level].max_lazy; @@ -564,8 +550,6 @@ local void fill_window() memcpy((char*)window, (char*)window+WSIZE, (unsigned)WSIZE); match_start -= WSIZE; strstart -= WSIZE; /* we now have strstart >= MAX_DIST: */ - if (rsync_chunk_end != 0xFFFFFFFFUL) - rsync_chunk_end -= WSIZE; block_start -= (long) WSIZE; @@ -595,44 +579,13 @@ local void fill_window() } } -local void rsync_roll(unsigned start, unsigned num) -{ - unsigned i; - - if (start < RSYNC_WIN) { - /* before window fills. */ - for (i = start; i < RSYNC_WIN; i++) { - if (i == start + num) return; - rsync_sum += (ulg)window[i]; - } - num -= (RSYNC_WIN - start); - start = RSYNC_WIN; - } - - /* buffer after window full */ - for (i = start; i < start+num; i++) { - /* New character in */ - rsync_sum += (ulg)window[i]; - /* Old character out */ - rsync_sum -= (ulg)window[i - RSYNC_WIN]; - if (rsync_chunk_end == 0xFFFFFFFFUL && RSYNC_SUM_MATCH(rsync_sum)) - rsync_chunk_end = i; - } -} - -/* =========================================================================== - * Set rsync_chunk_end if window sum matches magic value. - */ -#define RSYNC_ROLL(s, n) \ - do { if (rsync) rsync_roll((s), (n)); } while(0) - /* =========================================================================== * Flush the current block, with given end-of-file flag. * IN assertion: strstart is set to the end of the current match. */ #define FLUSH_BLOCK(eof) \ flush_block(block_start >= 0L ? (char*)&window[(unsigned)block_start] : \ - (char*)NULL, (long)strstart - block_start, flush-1, (eof)) + (char*)NULL, (long)strstart - block_start, (eof)) /* =========================================================================== * Processes a new input file and return its compressed length. This @@ -643,7 +596,7 @@ local void rsync_roll(unsigned start, unsigned num) local off_t deflate_fast() { IPos hash_head; /* head of the hash chain */ - int flush = 0; /* set if current block must be flushed, 2=>and padded */ + int flush; /* set if current block must be flushed */ unsigned match_length = 0; /* length of best match */ prev_length = MIN_MATCH-1; @@ -673,8 +626,7 @@ local off_t deflate_fast() lookahead -= match_length; - RSYNC_ROLL(strstart, match_length); - /* Insert new strings in the hash table only if the match length + /* Insert new strings in the hash table only if the match length * is not too large. This saves time but degrades compression. */ if (match_length <= max_insert_length) { @@ -702,14 +654,9 @@ local off_t deflate_fast() /* No match, output a literal byte */ Tracevv((stderr,"%c",window[strstart])); flush = ct_tally (0, window[strstart]); - RSYNC_ROLL(strstart, 1); lookahead--; strstart++; } - if (rsync && strstart > rsync_chunk_end) { - flush = 2; - rsync_chunk_end = 0xFFFFFFFFUL; - } if (flush) FLUSH_BLOCK(0), block_start = strstart; /* Make sure that we always have enough lookahead, except @@ -732,7 +679,7 @@ off_t deflate() { IPos hash_head; /* head of hash chain */ IPos prev_match; /* previous match */ - int flush = 0; /* set if current block must be flushed */ + int flush; /* set if current block must be flushed */ int match_available = 0; /* set if previous match exists */ register unsigned match_length = MIN_MATCH-1; /* length of best match */ @@ -783,7 +730,6 @@ off_t deflate() */ lookahead -= prev_length-1; prev_length -= 2; - RSYNC_ROLL(strstart, prev_length+1); do { strstart++; INSERT_STRING(strstart, hash_head); @@ -796,38 +742,24 @@ off_t deflate() match_available = 0; match_length = MIN_MATCH-1; strstart++; - - if (rsync && strstart > rsync_chunk_end) { - rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; - } if (flush) FLUSH_BLOCK(0), block_start = strstart; + } else if (match_available) { /* If there was no match at the previous position, output a * single literal. If there was a match but the current match * is longer, truncate the previous match to a single literal. */ Tracevv((stderr,"%c",window[strstart-1])); - flush = ct_tally (0, window[strstart-1]); - if (rsync && strstart > rsync_chunk_end) { - rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; - } - if (flush) FLUSH_BLOCK(0), block_start = strstart; - RSYNC_ROLL(strstart, 1); + if (ct_tally (0, window[strstart-1])) { + FLUSH_BLOCK(0), block_start = strstart; + } strstart++; lookahead--; } else { /* There is no previous match to compare with, wait for * the next step to decide. */ - if (rsync && strstart > rsync_chunk_end) { - rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; - FLUSH_BLOCK(0), block_start = strstart; - } match_available = 1; - RSYNC_ROLL(strstart, 1); strstart++; lookahead--; }