gzip/patches/gzip-1.3.13-rsync.patch

Index: gzip-1.5/deflate.c
===================================================================
--- gzip-1.5.orig/deflate.c
+++ gzip-1.5/deflate.c
@@ -131,6 +131,14 @@
 #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.
  */
@@ -212,6 +220,8 @@ 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
@@ -314,6 +324,10 @@ 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;
@@ -550,6 +564,8 @@ 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;
 
@@ -579,13 +595,46 @@ 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, (eof))
+                (char*)NULL, (long)strstart - block_start, flush-1, (eof)) 
 
 /* ===========================================================================
  * Processes a new input file and return its compressed length. This
@@ -596,7 +645,7 @@ local void fill_window()
 local off_t deflate_fast()
 {
     IPos hash_head; /* head of the hash chain */
-    int flush;      /* set if current block must be flushed */
+    int flush;      /* set if current block must be flushed, 2=>and padded  */ 
     unsigned match_length = 0;  /* length of best match */
 
     prev_length = MIN_MATCH-1;
@@ -625,7 +674,8 @@ local off_t deflate_fast()
             flush = ct_tally(strstart-match_start, match_length - MIN_MATCH);
 
             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.
              */
@@ -654,9 +704,14 @@ 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
@@ -730,6 +785,7 @@ off_t deflate()
              */
             lookahead -= prev_length-1;
             prev_length -= 2;
+            RSYNC_ROLL(strstart, prev_length+1);
             do {
                 strstart++;
                 INSERT_STRING(strstart, hash_head);
@@ -742,24 +798,40 @@ off_t deflate()
             match_available = 0;
             match_length = MIN_MATCH-1;
             strstart++;
-            if (flush) FLUSH_BLOCK(0), block_start = 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]));
-            if (ct_tally (0, window[strstart-1])) {
-                FLUSH_BLOCK(0), block_start = strstart;
+            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);
             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--;
         }
Index: gzip-1.5/doc/gzip.texi
===================================================================
--- gzip-1.5.orig/doc/gzip.texi
+++ gzip-1.5/doc/gzip.texi
@@ -353,6 +353,14 @@ specified on the command line are direct
 into the directory and compress all the files it finds there (or
 decompress them in the case of @command{gunzip}).
 
+@item --rsyncable
+While compressing, synchronize the output occasionally based on the
+input.  This reduces compression by about 1 percent most cases, but
+means that the @code{rsync} program can take advantage of similarities
+in the uncompressed input when syncronizing two files compressed with
+this flag.  @code{gunzip} cannot tell the difference between a
+compressed file created with this option, and one created without it.
+
 @item --suffix @var{suf}
 @itemx -S @var{suf}
 Use suffix @var{suf} instead of @samp{.gz}.  Any suffix can be
Index: gzip-1.5/gzip.c
===================================================================
--- gzip-1.5.orig/gzip.c
+++ gzip-1.5/gzip.c
@@ -213,6 +213,7 @@ int  ofd;                  /* output fil
 unsigned insize;           /* valid bytes in inbuf */
 unsigned inptr;            /* index of next byte to be processed in inbuf */
 unsigned outcnt;           /* bytes in output buffer */
+int rsync = 0;             /* make ryncable chunks */
 
 static int handled_sig[] =
   {
@@ -270,7 +271,7 @@ static const struct option longopts[] =
     {"best",       0, 0, '9'}, /* compress better */
     {"lzw",        0, 0, 'Z'}, /* make output compatible with old compress */
     {"bits",       1, 0, 'b'}, /* max number of bits per code (implies -Z) */
-
+    {"rsyncable",  0, 0, 'R'}, /* make rsync-friendly archive */ 
     { 0, 0, 0, 0 }
 };
 
@@ -353,6 +354,7 @@ local void help()
  "  -Z, --lzw         produce output compatible with old compress",
  "  -b, --bits=BITS   max number of bits per code (implies -Z)",
 #endif
+ "    --rsyncable   Make rsync-friendly archive",  
  "",
  "With no FILE, or when FILE is -, read standard input.",
  "",
@@ -482,6 +484,9 @@ int main (int argc, char **argv)
             recursive = 1;
 #endif
             break;
+            
+        case 'R':
+            rsync = 1; break;
         case 'S':
 #ifdef NO_MULTIPLE_DOTS
             if (*optarg == '.') optarg++;
Index: gzip-1.5/gzip.h
===================================================================
--- gzip-1.5.orig/gzip.h
+++ gzip-1.5/gzip.h
@@ -140,6 +140,7 @@ EXTERN(uch, window);         /* Sliding
 extern unsigned insize; /* valid bytes in inbuf */
 extern unsigned inptr;  /* index of next byte to be processed in inbuf */
 extern unsigned outcnt; /* bytes in output buffer */
+extern int rsync;  /* deflate into rsyncable chunks */ 
 
 extern off_t bytes_in;   /* number of input bytes */
 extern off_t bytes_out;  /* number of output bytes */
@@ -287,7 +288,7 @@ extern off_t deflate (void);
         /* in trees.c */
 extern void ct_init     (ush *attr, int *method);
 extern int  ct_tally    (int dist, int lc);
-extern off_t flush_block (char *buf, ulg stored_len, int eof);
+extern off_t flush_block (char *buf, ulg stored_len, int pad, int eof);
 
         /* in bits.c */
 extern void     bi_init    (file_t zipfile);
Index: gzip-1.5/trees.c
===================================================================
--- gzip-1.5.orig/trees.c
+++ gzip-1.5/trees.c
@@ -856,9 +856,10 @@ local void send_all_trees(lcodes, dcodes
  * trees or store, and output the encoded block to the zip file. This function
  * returns the total compressed length for the file so far.
  */
-off_t flush_block(buf, stored_len, eof)
+off_t flush_block(buf, stored_len, pad, eof)  
     char *buf;        /* input block, or NULL if too old */
     ulg stored_len;   /* length of input block */
+    int pad;          /* pad output to byte boundary */ 
     int eof;          /* true if this is the last block for a file */
 {
     ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
@@ -951,6 +952,10 @@ off_t flush_block(buf, stored_len, eof)
         Assert (input_len == bytes_in, "bad input size");
         bi_windup();
         compressed_len += 7;  /* align on byte boundary */
+    } else if (pad && (compressed_len % 8) != 0) {
+        send_bits((STORED_BLOCK<<1)+eof, 3);  /* send block type */
+        compressed_len = (compressed_len + 3 + 7) & ~7L;
+        copy_block(buf, 0, 1); /* with header */
     }
 
     return compressed_len >> 3;
1	niro	2540	Index: gzip-1.5/deflate.c
2			===================================================================
3			--- gzip-1.5.orig/deflate.c
4			+++ gzip-1.5/deflate.c
5			@@ -131,6 +131,14 @@
6			#endif
7			/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */
8
9			+#ifndef RSYNC_WIN
10			+# define RSYNC_WIN 4096
11			+#endif
12			+/* Size of rsync window, must be < MAX_DIST */
13			+
14			+#define RSYNC_SUM_MATCH(sum) ((sum) % RSYNC_WIN == 0)
15			+/* Whether window sum matches magic value */
16			+
17			/* ===========================================================================
18			* Local data used by the "longest match" routines.
19			*/
20			@@ -212,6 +220,8 @@ local int compr_level;
21			unsigned good_match;
22			/* Use a faster search when the previous match is longer than this */
23
24			+local ulg rsync_sum; /* rolling sum of rsync window */
25			+local ulg rsync_chunk_end; /* next rsync sequence point */
26
27			/* Values for max_lazy_match, good_match and max_chain_length, depending on
28			* the desired pack level (0..9). The values given below have been tuned to
29			@@ -314,6 +324,10 @@ void lm_init (pack_level, flags)
30			#endif
31			/* prev will be initialized on the fly */
32
33			+ /* rsync params */
34			+ rsync_chunk_end = 0xFFFFFFFFUL;
35			+ rsync_sum = 0;
36			+
37			/* Set the default configuration parameters:
38			*/
39			max_lazy_match = configuration_table[pack_level].max_lazy;
40			@@ -550,6 +564,8 @@ local void fill_window()
41			memcpy((char)window, (char)window+WSIZE, (unsigned)WSIZE);
42			match_start -= WSIZE;
43			strstart -= WSIZE; /* we now have strstart >= MAX_DIST: */
44			+ if (rsync_chunk_end != 0xFFFFFFFFUL)
45			+ rsync_chunk_end -= WSIZE;
46
47			block_start -= (long) WSIZE;
48
49			@@ -579,13 +595,46 @@ local void fill_window()
50			}
51			}
52
53			+local void rsync_roll(start, num)
54			+ unsigned start;
55			+ unsigned num;
56			+{
57			+ unsigned i;
58			+
59			+ if (start < RSYNC_WIN) {
60			+ /* before window fills. */
61			+ for (i = start; i < RSYNC_WIN; i++) {
62			+ if (i == start + num) return;
63			+ rsync_sum += (ulg)window[i];
64			+ }
65			+ num -= (RSYNC_WIN - start);
66			+ start = RSYNC_WIN;
67			+ }
68			+
69			+ /* buffer after window full */
70			+ for (i = start; i < start+num; i++) {
71			+ /* New character in */
72			+ rsync_sum += (ulg)window[i];
73			+ /* Old character out */
74			+ rsync_sum -= (ulg)window[i - RSYNC_WIN];
75			+ if (rsync_chunk_end == 0xFFFFFFFFUL && RSYNC_SUM_MATCH(rsync_sum))
76			+ rsync_chunk_end = i;
77			+ }
78			+}
79			+
80			+/* ===========================================================================
81			+ * Set rsync_chunk_end if window sum matches magic value.
82			+ */
83			+#define RSYNC_ROLL(s, n) \
84			+ do { if (rsync) rsync_roll((s), (n)); } while(0)
85			+
86			/* ===========================================================================
87			* Flush the current block, with given end-of-file flag.
88			* IN assertion: strstart is set to the end of the current match.
89			*/
90			#define FLUSH_BLOCK(eof) \
91			flush_block(block_start >= 0L ? (char*)&window[(unsigned)block_start] : \
92			- (char*)NULL, (long)strstart - block_start, (eof))
93			+ (char*)NULL, (long)strstart - block_start, flush-1, (eof))
94
95			/* ===========================================================================
96			* Processes a new input file and return its compressed length. This
97			@@ -596,7 +645,7 @@ local void fill_window()
98			local off_t deflate_fast()
99			{
100			IPos hash_head; /* head of the hash chain */
101			- int flush; /* set if current block must be flushed */
102			+ int flush; /* set if current block must be flushed, 2=>and padded */
103			unsigned match_length = 0; /* length of best match */
104
105			prev_length = MIN_MATCH-1;
106			@@ -625,7 +674,8 @@ local off_t deflate_fast()
107			flush = ct_tally(strstart-match_start, match_length - MIN_MATCH);
108
109			lookahead -= match_length;
110			-
111			+
112			+ RSYNC_ROLL(strstart, match_length);
113			/* Insert new strings in the hash table only if the match length
114			* is not too large. This saves time but degrades compression.
115			*/
116			@@ -654,9 +704,14 @@ local off_t deflate_fast()
117			/* No match, output a literal byte */
118			Tracevv((stderr,"%c",window[strstart]));
119			flush = ct_tally (0, window[strstart]);
120			+ RSYNC_ROLL(strstart, 1);
121			lookahead--;
122			strstart++;
123			}
124			+ if (rsync && strstart > rsync_chunk_end) {
125			+ rsync_chunk_end = 0xFFFFFFFFUL;
126			+ flush = 2;
127			+ }
128			if (flush) FLUSH_BLOCK(0), block_start = strstart;
129
130			/* Make sure that we always have enough lookahead, except
131			@@ -730,6 +785,7 @@ off_t deflate()
132			*/
133			lookahead -= prev_length-1;
134			prev_length -= 2;
135			+ RSYNC_ROLL(strstart, prev_length+1);
136			do {
137			strstart++;
138			INSERT_STRING(strstart, hash_head);
139			@@ -742,24 +798,40 @@ off_t deflate()
140			match_available = 0;
141			match_length = MIN_MATCH-1;
142			strstart++;
143			- if (flush) FLUSH_BLOCK(0), block_start = strstart;
144
145			+ if (rsync && strstart > rsync_chunk_end) {
146			+ rsync_chunk_end = 0xFFFFFFFFUL;
147			+ flush = 2;
148			+ }
149			+ if (flush) FLUSH_BLOCK(0), block_start = strstart;
150			} else if (match_available) {
151			/* If there was no match at the previous position, output a
152			* single literal. If there was a match but the current match
153			* is longer, truncate the previous match to a single literal.
154			*/
155			Tracevv((stderr,"%c",window[strstart-1]));
156			- if (ct_tally (0, window[strstart-1])) {
157			- FLUSH_BLOCK(0), block_start = strstart;
158			+ flush = ct_tally (0, window[strstart-1]);
159			+ if (rsync && strstart > rsync_chunk_end) {
160			+ rsync_chunk_end = 0xFFFFFFFFUL;
161			+ flush = 2;
162			}
163			+ if (flush) FLUSH_BLOCK(0), block_start = strstart;
164			+ RSYNC_ROLL(strstart, 1);
165			strstart++;
166			lookahead--;
167			} else {
168			/* There is no previous match to compare with, wait for
169			* the next step to decide.
170			*/
171			+ if (rsync && strstart > rsync_chunk_end) {
172			+ /* Reset huffman tree */
173			+ rsync_chunk_end = 0xFFFFFFFFUL;
174			+ flush = 2;
175			+ FLUSH_BLOCK(0), block_start = strstart;
176			+ }
177			+
178			match_available = 1;
179			+ RSYNC_ROLL(strstart, 1);
180			strstart++;
181			lookahead--;
182			}
183			Index: gzip-1.5/doc/gzip.texi
184			===================================================================
185			--- gzip-1.5.orig/doc/gzip.texi
186			+++ gzip-1.5/doc/gzip.texi
187			@@ -353,6 +353,14 @@ specified on the command line are direct
188			into the directory and compress all the files it finds there (or
189			decompress them in the case of @command{gunzip}).
190
191			+@item --rsyncable
192			+While compressing, synchronize the output occasionally based on the
193			+input. This reduces compression by about 1 percent most cases, but
194			+means that the @code{rsync} program can take advantage of similarities
195			+in the uncompressed input when syncronizing two files compressed with
196			+this flag. @code{gunzip} cannot tell the difference between a
197			+compressed file created with this option, and one created without it.
198			+
199			@item --suffix @var{suf}
200			@itemx -S @var{suf}
201			Use suffix @var{suf} instead of @samp{.gz}. Any suffix can be
202			Index: gzip-1.5/gzip.c
203			===================================================================
204			--- gzip-1.5.orig/gzip.c
205			+++ gzip-1.5/gzip.c
206			@@ -213,6 +213,7 @@ int ofd; /* output fil
207			unsigned insize; /* valid bytes in inbuf */
208			unsigned inptr; /* index of next byte to be processed in inbuf */
209			unsigned outcnt; /* bytes in output buffer */
210			+int rsync = 0; /* make ryncable chunks */
211
212			static int handled_sig[] =
213			{
214			@@ -270,7 +271,7 @@ static const struct option longopts[] =
215			{"best", 0, 0, '9'}, /* compress better */
216			{"lzw", 0, 0, 'Z'}, /* make output compatible with old compress */
217			{"bits", 1, 0, 'b'}, /* max number of bits per code (implies -Z) */
218			-
219			+ {"rsyncable", 0, 0, 'R'}, /* make rsync-friendly archive */
220			{ 0, 0, 0, 0 }
221			};
222
223			@@ -353,6 +354,7 @@ local void help()
224			" -Z, --lzw produce output compatible with old compress",
225			" -b, --bits=BITS max number of bits per code (implies -Z)",
226			#endif
227			+ " --rsyncable Make rsync-friendly archive",
228			"",
229			"With no FILE, or when FILE is -, read standard input.",
230			"",
231			@@ -482,6 +484,9 @@ int main (int argc, char **argv)
232			recursive = 1;
233			#endif
234			break;
235			+
236			+ case 'R':
237			+ rsync = 1; break;
238			case 'S':
239			#ifdef NO_MULTIPLE_DOTS
240			if (*optarg == '.') optarg++;
241			Index: gzip-1.5/gzip.h
242			===================================================================
243			--- gzip-1.5.orig/gzip.h
244			+++ gzip-1.5/gzip.h
245			@@ -140,6 +140,7 @@ EXTERN(uch, window); /* Sliding
246			extern unsigned insize; /* valid bytes in inbuf */
247			extern unsigned inptr; /* index of next byte to be processed in inbuf */
248			extern unsigned outcnt; /* bytes in output buffer */
249			+extern int rsync; /* deflate into rsyncable chunks */
250
251			extern off_t bytes_in; /* number of input bytes */
252			extern off_t bytes_out; /* number of output bytes */
253			@@ -287,7 +288,7 @@ extern off_t deflate (void);
254			/* in trees.c */
255			extern void ct_init (ush attr, int method);
256			extern int ct_tally (int dist, int lc);
257			-extern off_t flush_block (char *buf, ulg stored_len, int eof);
258			+extern off_t flush_block (char *buf, ulg stored_len, int pad, int eof);
259
260			/* in bits.c */
261			extern void bi_init (file_t zipfile);
262			Index: gzip-1.5/trees.c
263			===================================================================
264			--- gzip-1.5.orig/trees.c
265			+++ gzip-1.5/trees.c
266			@@ -856,9 +856,10 @@ local void send_all_trees(lcodes, dcodes
267			* trees or store, and output the encoded block to the zip file. This function
268			* returns the total compressed length for the file so far.
269			*/
270			-off_t flush_block(buf, stored_len, eof)
271			+off_t flush_block(buf, stored_len, pad, eof)
272			char buf; / input block, or NULL if too old */
273			ulg stored_len; /* length of input block */
274			+ int pad; /* pad output to byte boundary */
275			int eof; /* true if this is the last block for a file */
276			{
277			ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
278			@@ -951,6 +952,10 @@ off_t flush_block(buf, stored_len, eof)
279			Assert (input_len == bytes_in, "bad input size");
280			bi_windup();
281			compressed_len += 7; /* align on byte boundary */
282			+ } else if (pad && (compressed_len % 8) != 0) {
283			+ send_bits((STORED_BLOCK<<1)+eof, 3); /* send block type */
284			+ compressed_len = (compressed_len + 3 + 7) & ~7L;
285			+ copy_block(buf, 0, 1); /* with header */
286			}
287
288			return compressed_len >> 3;