/*
- Copyright (C) Andrew Tridgell 1996
- Copyright (C) Paul Mackerras 1996
-
- 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 of the License, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
+ * Block matching used by the file-transfer code.
+ *
+ * Copyright (C) 1996 Andrew Tridgell
+ * Copyright (C) 1996 Paul Mackerras
+ * Copyright (C) 2003-2007 Wayne Davison
+ *
+ * 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 of the License, 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, visit the http://fsf.org website.
+ */
#include "rsync.h"
extern struct stats stats;
-static uint32 tablesize;
+#define TABLESIZE (1<<16)
+
static int32 *hash_table;
-#define SUM2HASH(sum) ((sum)%tablesize)
+#define SUM2HASH2(s1,s2) (((s1) + (s2)) & 0xFFFF)
+#define SUM2HASH(sum) SUM2HASH2((sum)&0xFFFF,(sum)>>16)
static void build_hash_table(struct sum_struct *s)
{
int32 i;
- uint32 prior_size = tablesize;
-
- /* Dynamically calculate the hash table size so that the hash load
- * for big files is about 80%. This number must be odd or s2 will
- * not be able to span the entire set. */
- tablesize = (uint32)(s->count/8) * 10 + 11;
- if (tablesize < 65537)
- tablesize = 65537; /* a prime number */
- if (tablesize != prior_size) {
- free(hash_table);
- hash_table = new_array(int32, tablesize);
+
+ if (!hash_table) {
+ hash_table = new_array(int32, TABLESIZE);
if (!hash_table)
out_of_memory("build_hash_table");
}
- memset(hash_table, 0xFF, tablesize * sizeof hash_table[0]);
+ memset(hash_table, 0xFF, TABLESIZE * sizeof hash_table[0]);
for (i = 0; i < s->count; i++) {
uint32 t = SUM2HASH(s->sums[i].sum1);
static void matched(int f, struct sum_struct *s, struct map_struct *buf,
OFF_T offset, int32 i)
{
- int32 n = offset - last_match; /* max value: block_size (int32) */
+ int32 n = (int32)(offset - last_match); /* max value: block_size (int32) */
int32 j;
if (verbose > 2 && i >= 0) {
static void hash_search(int f,struct sum_struct *s,
struct map_struct *buf, OFF_T len)
{
- OFF_T offset, end, backup;
- int32 k, want_i;
+ OFF_T offset, end;
+ int32 k, want_i, backup;
char sum2[SUM_LENGTH];
uint32 s1, s2, sum;
int more;
int done_csum2 = 0;
int32 i;
- if (verbose > 4)
- rprintf(FINFO,"offset=%.0f sum=%08x\n",(double)offset,sum);
+ if (verbose > 4) {
+ rprintf(FINFO, "offset=%.0f sum=%04x%04x\n",
+ (double)offset, s2 & 0xFFFF, s1 & 0xFFFF);
+ }
- i = hash_table[SUM2HASH(sum)];
+ i = hash_table[SUM2HASH2(s1,s2)];
if (i < 0)
goto null_hash;
+ sum = (s1 & 0xffff) | (s2 << 16);
hash_hits++;
do {
int32 l;
} while ((i = s->sums[i].chain) >= 0);
null_hash:
- backup = offset - last_match;
+ backup = (int32)(offset - last_match);
/* We sometimes read 1 byte prior to last_match... */
if (backup < 0)
backup = 0;
s2 += s1;
} else
--k;
- sum = (s1 & 0xffff) | (s2 << 16);
/* By matching early we avoid re-reading the
data 3 times in the case where a token
**/
void match_sums(int f, struct sum_struct *s, struct map_struct *buf, OFF_T len)
{
- char file_sum[MD4_SUM_LENGTH];
+ char file_sum[MAX_DIGEST_LEN];
+ int sum_len;
last_match = 0;
false_alarms = 0;
sum_init(checksum_seed);
- if (append_mode) {
- OFF_T j = 0;
- for (j = CHUNK_SIZE; j < s->flength; j += CHUNK_SIZE) {
- if (buf && do_progress)
- show_progress(last_match, buf->file_size);
- sum_update(map_ptr(buf, last_match, CHUNK_SIZE),
- CHUNK_SIZE);
- last_match = j;
- }
- if (last_match < s->flength) {
- int32 len = s->flength - last_match;
- if (buf && do_progress)
- show_progress(last_match, buf->file_size);
- sum_update(map_ptr(buf, last_match, len), len);
- last_match = s->flength;
+ if (append_mode > 0) {
+ if (append_mode == 2) {
+ OFF_T j = 0;
+ for (j = CHUNK_SIZE; j < s->flength; j += CHUNK_SIZE) {
+ if (buf && do_progress)
+ show_progress(last_match, buf->file_size);
+ sum_update(map_ptr(buf, last_match, CHUNK_SIZE),
+ CHUNK_SIZE);
+ last_match = j;
+ }
+ if (last_match < s->flength) {
+ int32 n = (int32)(s->flength - last_match);
+ if (buf && do_progress)
+ show_progress(last_match, buf->file_size);
+ sum_update(map_ptr(buf, last_match, n), n);
+ }
}
+ last_match = s->flength;
s->count = 0;
}
if (verbose > 2)
rprintf(FINFO,"built hash table\n");
- hash_search(f,s,buf,len);
+ hash_search(f, s, buf, len);
if (verbose > 2)
rprintf(FINFO,"done hash search\n");
matched(f, s, buf, len, -1);
}
- sum_end(file_sum);
+ sum_len = sum_end(file_sum);
/* If we had a read error, send a bad checksum. */
if (buf && buf->status != 0)
file_sum[0]++;
if (verbose > 2)
rprintf(FINFO,"sending file_sum\n");
- write_buf(f,file_sum,MD4_SUM_LENGTH);
+ write_buf(f, file_sum, sum_len);
if (verbose > 2)
rprintf(FINFO, "false_alarms=%d hash_hits=%d matches=%d\n",
Matt McCutchen's Web Site / rsync / rsync.git / blobdiff