+++ /dev/null
-NOTE: this patch is for _gzip_!
-
-This is pending for actual inclusion in gzip. It is currently being
-tried out in the default gzip for Debian Sarge, and may go into the
-upstream gzip at somepoint in the not-too-distant future.
-
---- gzip-1.3.5/deflate.c 1999-10-07 23:46:28 -0700
-+++ rsyncable/deflate.c 2005-02-05 09:40:33 -0800
-@@ -122,6 +122,14 @@
- #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.
- */
-@@ -203,6 +211,8 @@
- 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
-@@ -301,6 +311,10 @@
- #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;
-@@ -537,6 +551,8 @@
- 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;
-
-@@ -564,13 +580,46 @@
- }
- }
-
-+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
-@@ -581,7 +630,7 @@
- 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;
-@@ -610,6 +659,7 @@
-
- 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.
- */
-@@ -638,9 +688,14 @@
- /* 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
-@@ -713,6 +768,7 @@
- */
- lookahead -= prev_length-1;
- prev_length -= 2;
-+ RSYNC_ROLL(strstart, prev_length+1);
- do {
- strstart++;
- INSERT_STRING(strstart, hash_head);
-@@ -725,24 +781,39 @@
- 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--;
- }
---- gzip-1.3.5/gzip.c 2002-09-28 00:38:43 -0700
-+++ rsyncable/gzip.c 2005-02-05 09:40:33 -0800
-@@ -256,6 +256,7 @@
- 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 */
-
- struct option longopts[] =
- {
-@@ -285,6 +286,7 @@
- {"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 }
- };
-
-@@ -365,6 +367,7 @@
- " -Z --lzw produce output compatible with old compress",
- " -b --bits maxbits max number of bits per code (implies -Z)",
- #endif
-+ " --rsyncable Make rsync-friendly archive",
- " file... files to (de)compress. If none given, use standard input.",
- "Report bugs to <bug-gzip@gnu.org>.",
- 0};
-@@ -543,6 +546,9 @@
- #else
- recursive = 1; break;
- #endif
-+ case 'R':
-+ rsync = 1; break;
-+
- case 'S':
- #ifdef NO_MULTIPLE_DOTS
- if (*optarg == '.') optarg++;
---- gzip-1.3.5/gzip.h 2001-09-30 23:53:41 -0700
-+++ rsyncable/gzip.h 2005-02-05 09:40:33 -0800
-@@ -133,6 +133,7 @@
- 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 */
-@@ -281,7 +282,7 @@
- /* in trees.c */
- void ct_init OF((ush *attr, int *method));
- int ct_tally OF((int dist, int lc));
--off_t flush_block OF((char *buf, ulg stored_len, int eof));
-+off_t flush_block OF((char *buf, ulg stored_len, int pad, int eof));
-
- /* in bits.c */
- void bi_init OF((file_t zipfile));
---- gzip-1.3.5/gzip.texi 2002-09-29 23:57:29 -0700
-+++ rsyncable/gzip.texi 2005-02-05 09:40:33 -0800
-@@ -334,6 +334,14 @@
- into the directory and compress all the files it finds there (or
- decompress them in the case of @code{gunzip}).
-
-+@item --rsyncable
-+While compressing, synchronize the output occasionally based on the
-+input. This increases size by less than 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 @samp{@var{suf}} instead of @samp{.gz}. Any suffix can be
---- gzip-1.3.5/trees.c 1999-10-05 22:00:00 -0700
-+++ rsyncable/trees.c 2005-02-05 09:40:33 -0800
-@@ -46,12 +46,13 @@
- * void ct_tally (int dist, int lc);
- * Save the match info and tally the frequency counts.
- *
-- * off_t flush_block (char *buf, ulg stored_len, int eof)
-+ * off_t flush_block (char *buf, ulg stored_len, int pad, int eof)
- * Determine the best encoding for the current block: dynamic trees,
- * static trees or store, and output the encoded block to the zip
-- * file. Returns the total compressed length for the file so far.
-- *
-- */
-+ * file. If pad is set, pads the block to the next
-+ * byte. Returns the total compressed length for the file so
-+ * far.
-+ * */
-
- #include <config.h>
- #include <ctype.h>
-@@ -847,9 +848,10 @@
- * 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 */
-@@ -941,6 +943,10 @@
- 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;
Matt McCutchen's Web Site / rsync / rsync-patches.git / blobdiff