X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=deflate.c;h=0950391ee88ba44a67a36ce4f1b14c87f79ebaa3;hb=23f83fdd144ead232457bbbe34b14ff4b26aa8cf;hp=629e8d7f9bcade3c7aa826aef7f702bda8a13015;hpb=e7921f54c622e3b32e525f345bc34308821e4ae0;p=debian%2Fgzip

diff --git a/deflate.c b/deflate.c
index 629e8d7..0950391 100644
--- a/deflate.c
+++ b/deflate.c
@@ -1,11 +1,11 @@
 /* deflate.c -- compress data using the deflation algorithm
 
-   Copyright (C) 1999, 2006 Free Software Foundation, Inc.
+   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 2, or (at your option)
+   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,
@@ -81,10 +81,6 @@
 #include "gzip.h"
 #include "lzw.h" /* just for consistency checking */
 
-#ifdef RCSID
-static char rcsid[] = "$Id: deflate.c,v 1.5 2006/12/07 23:53:00 eggert Exp $";
-#endif
-
 /* ===========================================================================
  * Configuration parameters
  */
@@ -135,14 +131,6 @@ static char rcsid[] = "$Id: deflate.c,v 1.5 2006/12/07 23:53:00 eggert Exp $";
 #endif
 /* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
 
-#ifndef RSYNC_WIN
-#  define RSYNC_WIN 4096
-#endif
-/* Size of rsync window, must be < MAX_DIST */
-
-#define RSYNC_SUM_MATCH(sum) ((sum) % RSYNC_WIN == 0)
-/* Whether window sum matches magic value */
-
 /* ===========================================================================
  * Local data used by the "longest match" routines.
  */
@@ -224,8 +212,6 @@ local int compr_level;
 unsigned near 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
@@ -265,9 +251,6 @@ local config configuration_table[10] = {
  * meaning.
  */
 
-#define EQUAL 0
-/* result of memcmp for equal strings */
-
 /* ===========================================================================
  *  Prototypes for local functions.
  */
@@ -324,10 +307,6 @@ 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;
@@ -518,7 +497,7 @@ 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);
@@ -564,8 +543,6 @@ 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;
 
@@ -593,46 +570,13 @@ local void fill_window()
     }
 }
 
-local void rsync_roll(start, num)
-    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 +587,7 @@ 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;
@@ -673,7 +617,6 @@ 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
              * is not too large. This saves time but degrades compression.
              */
@@ -702,14 +645,9 @@ 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) {
-	    rsync_chunk_end = 0xFFFFFFFFUL;
-	    flush = 2;
-	} 
         if (flush) FLUSH_BLOCK(0), block_start = strstart;
 
         /* Make sure that we always have enough lookahead, except
@@ -783,7 +721,6 @@ off_t deflate()
              */
             lookahead -= prev_length-1;
             prev_length -= 2;
-	    RSYNC_ROLL(strstart, prev_length+1);
             do {
                 strstart++;
                 INSERT_STRING(strstart, hash_head);
@@ -796,39 +733,24 @@ 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) {
-		/* Reset huffman tree */
-		rsync_chunk_end = 0xFFFFFFFFUL;
-		flush = 2;
-		FLUSH_BLOCK(0), block_start = strstart;
-	    }
             match_available = 1;
-	    RSYNC_ROLL(strstart, 1);
             strstart++;
             lookahead--;
         }