Revert "patch to improve behavior of zdiff when file is compressed without extension"

[debian/gzip] / deflate.c

diff --git a/deflate.c b/deflate.c
index e83b5a383914aeb3a4d2626312aeb653a431e4d4..a551fa3a409d640905fed9e329d10038731f13a5 100644 (file)
--- a/deflate.c
+++ b/deflate.c
@@ -132,11 +132,11 @@
 /* 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 */
 
 /* ===========================================================================
@@ -338,6 +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
@@ -580,6 +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;
         }
@@ -625,7 +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
@@ -636,7 +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;
@@ -699,10 +702,14 @@ local off_t deflate_fast()
             lookahead--;
            strstart++;
         }
-       if (rsync && strstart > rsync_chunk_end) {
-           rsync_chunk_end = 0xFFFFFFFFUL;
-           flush = 2;
-       } 
+        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 (flush) FLUSH_BLOCK(0), block_start = strstart;
 
         /* Make sure that we always have enough lookahead, except
@@ -791,8 +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) {
@@ -803,8 +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);
@@ -815,9 +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;