X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=deflate.c;h=a551fa3a409d640905fed9e329d10038731f13a5;hb=1818209f5c4879522d69a09bedb0553543d6889e;hp=bc4c8d4f571982948f9fb37d64e9b7bf15dd67c6;hpb=db00b4e39677b0dbf3ea6f7694e0eac7be4ef141;p=debian%2Fgzip diff --git a/deflate.c b/deflate.c index bc4c8d4..a551fa3 100644 --- a/deflate.c +++ b/deflate.c @@ -1,8 +1,21 @@ /* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1992-1993 Jean-loup Gailly - * This is free software; you can redistribute it and/or modify it under the - * terms of the GNU General Public License, see the file COPYING. - */ + + Copyright (C) 1999, 2006, 2009-2010 Free Software Foundation, Inc. + Copyright (C) 1992-1993 Jean-loup Gailly + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ /* * PURPOSE @@ -68,10 +81,6 @@ #include "gzip.h" #include "lzw.h" /* just for consistency checking */ -#ifdef RCSID -static char rcsid[] = "$Id: deflate.c,v 0.15 1993/06/24 10:53:53 jloup Exp $"; -#endif - /* =========================================================================== * Configuration parameters */ @@ -123,11 +132,11 @@ static char rcsid[] = "$Id: deflate.c,v 0.15 1993/06/24 10:53:53 jloup Exp $"; /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ #ifndef RSYNC_WIN -# define RSYNC_WIN 4096 +# define RSYNC_WIN 8192 #endif /* Size of rsync window, must be < MAX_DIST */ -#define RSYNC_SUM_MATCH(sum) ((sum) % RSYNC_WIN == 0) +#define RSYNC_SUM_MATCH(sum) (((sum) & (RSYNC_WIN - 1)) == 0) /* Whether window sum matches magic value */ /* =========================================================================== @@ -252,9 +261,6 @@ local config configuration_table[10] = { * meaning. */ -#define EQUAL 0 -/* result of memcmp for equal strings */ - /* =========================================================================== * Prototypes for local functions. */ @@ -300,7 +306,7 @@ void lm_init (pack_level, flags) { register unsigned j; - if (pack_level < 1 || pack_level > 9) error("bad pack level"); + if (pack_level < 1 || pack_level > 9) gzip_error ("bad pack level"); compr_level = pack_level; /* Initialize the hash table. */ @@ -332,6 +338,7 @@ void lm_init (pack_level, flags) strstart = 0; block_start = 0L; + rsync_chunk_end = 0xFFFFFFFFUL; #ifdef ASMV match_init(); /* initialize the asm code */ #endif @@ -505,11 +512,11 @@ local void check_match(start, match, length) { /* check that the match is indeed a match */ if (memcmp((char*)window + match, - (char*)window + start, length) != EQUAL) { + (char*)window + start, length) != 0) { fprintf(stderr, " start %d, match %d, length %d\n", start, match, length); - error("invalid match"); + gzip_error ("invalid match"); } if (verbose > 1) { fprintf(stderr,"\\[%d,%d]", start-match, length); @@ -574,6 +581,8 @@ local void fill_window() n = read_buf((char*)window+strstart+lookahead, more); if (n == 0 || n == (unsigned)EOF) { eofile = 1; + /* Don't let garbage pollute the dictionary. */ + memzero (window + strstart + lookahead, MIN_MATCH - 1); } else { lookahead += n; } @@ -619,7 +628,7 @@ local void rsync_roll(start, num) */ #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 @@ -630,7 +639,7 @@ local void rsync_roll(start, num) local off_t deflate_fast() { IPos hash_head; /* head of the hash chain */ - int flush; /* 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; @@ -643,8 +652,8 @@ local off_t deflate_fast() /* Find the longest match, discarding those <= prev_length. * At this point we have always match_length < MIN_MATCH */ - if (hash_head != NIL && strstart - hash_head <= MAX_DIST && - strstart <= window_size - MIN_LOOKAHEAD) { + if (hash_head != NIL && strstart - hash_head <= MAX_DIST + && strstart <= window_size - MIN_LOOKAHEAD) { /* To simplify the code, we prevent matches with the string * of window index 0 (in particular we have to avoid a match * of the string with itself at the start of the input file). @@ -675,7 +684,7 @@ local off_t deflate_fast() * the next lookahead bytes will be emitted as literals. */ } while (--match_length != 0); - strstart++; + strstart++; } else { strstart += match_length; match_length = 0; @@ -691,12 +700,16 @@ local off_t deflate_fast() flush = ct_tally (0, window[strstart]); RSYNC_ROLL(strstart, 1); lookahead--; - strstart++; + strstart++; + } + if (rsync && strstart > rsync_chunk_end) { + ush attr = 0; /* ascii/binary flag */ + + flush = 1; + /* Reset huffman tree */ + ct_init(&attr, &method); + rsync_chunk_end = 0xFFFFFFFFUL; } - if (rsync && strstart > rsync_chunk_end) { - rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; - } if (flush) FLUSH_BLOCK(0), block_start = strstart; /* Make sure that we always have enough lookahead, except @@ -739,7 +752,7 @@ off_t deflate() if (hash_head != NIL && prev_length < max_lazy_match && strstart - hash_head <= MAX_DIST && - strstart <= window_size - MIN_LOOKAHEAD) { + strstart <= window_size - MIN_LOOKAHEAD) { /* To simplify the code, we prevent matches with the string * of window index 0 (in particular we have to avoid a match * of the string with itself at the start of the input file). @@ -785,8 +798,12 @@ off_t deflate() strstart++; if (rsync && strstart > rsync_chunk_end) { + ush attr = 0; /* ascii/binary flag */ + + /* Reset huffman tree */ + ct_init(&attr, &method); rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; + flush = 1; } if (flush) FLUSH_BLOCK(0), block_start = strstart; } else if (match_available) { @@ -797,8 +814,13 @@ off_t deflate() Tracevv((stderr,"%c",window[strstart-1])); flush = ct_tally (0, window[strstart-1]); if (rsync && strstart > rsync_chunk_end) { + ush attr = 0; /* ascii/binary flag */ + + /* Reset huffman tree */ + ct_init(&attr, &method); rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; + + flush = 1; } if (flush) FLUSH_BLOCK(0), block_start = strstart; RSYNC_ROLL(strstart, 1); @@ -809,9 +831,12 @@ off_t deflate() * the next step to decide. */ if (rsync && strstart > rsync_chunk_end) { + ush attr = 0; /* ascii/binary flag */ + /* Reset huffman tree */ + ct_init(&attr, &method); rsync_chunk_end = 0xFFFFFFFFUL; - flush = 2; + FLUSH_BLOCK(0), block_start = strstart; } match_available = 1;