/*
- 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 version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.,
+ * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
+ */
#include "rsync.h"
int updating_basis_file;
static int false_alarms;
-static int tag_hits;
+static int hash_hits;
static int matches;
static int64 data_transfer;
static int total_false_alarms;
-static int total_tag_hits;
+static int total_hash_hits;
static int total_matches;
extern struct stats stats;
-static uint32 tablesize;
-static int32 *sum_table;
+#define TABLESIZE (1<<16)
+
+static int32 *hash_table;
-#define gettag2(s1,s2) gettag((s1) + ((s2)<<16))
-#define gettag(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(sum_table);
- sum_table = new_array(int32, tablesize);
- if (!sum_table)
+
+ if (!hash_table) {
+ hash_table = new_array(int32, TABLESIZE);
+ if (!hash_table)
out_of_memory("build_hash_table");
}
- memset(sum_table, 0xFF, tablesize * sizeof sum_table[0]);
+ memset(hash_table, 0xFF, TABLESIZE * sizeof hash_table[0]);
for (i = 0; i < s->count; i++) {
- uint32 t = gettag(s->sums[i].sum1);
- s->sums[i].chain = sum_table[t];
- sum_table[t] = i;
+ uint32 t = SUM2HASH(s->sums[i].sum1);
+ s->sums[i].chain = hash_table[t];
+ hash_table[t] = i;
}
}
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;
}
do {
- uint32 t = gettag2(s1,s2);
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[SUM2HASH2(s1,s2)];
+ if (i < 0)
+ goto null_hash;
sum = (s1 & 0xffff) | (s2 << 16);
- tag_hits++;
- for (i = sum_table[t]; i >= 0; i = s->sums[i].chain) {
+ hash_hits++;
+ do {
int32 l;
if (sum != s->sums[i].sum1)
s2 = sum >> 16;
matches++;
break;
- }
+ } while ((i = s->sums[i].chain) >= 0);
- backup = offset - last_match;
+ null_hash:
+ backup = (int32)(offset - last_match);
/* We sometimes read 1 byte prior to last_match... */
if (backup < 0)
backup = 0;
**/
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;
- tag_hits = 0;
+ hash_hits = 0;
matches = 0;
data_transfer = 0;
sum_init(checksum_seed);
- if (append_mode) {
+ if (append_mode > 0) {
OFF_T j = 0;
for (j = CHUNK_SIZE; j < s->flength; j += CHUNK_SIZE) {
if (buf && do_progress)
last_match = j;
}
if (last_match < s->flength) {
- int32 len = s->flength - last_match;
+ 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, len), len);
+ 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 tag_hits=%d matches=%d\n",
- false_alarms, tag_hits, matches);
+ rprintf(FINFO, "false_alarms=%d hash_hits=%d matches=%d\n",
+ false_alarms, hash_hits, matches);
- total_tag_hits += tag_hits;
+ total_hash_hits += hash_hits;
total_false_alarms += false_alarms;
total_matches += matches;
stats.literal_data += data_transfer;
return;
rprintf(FINFO,
- "total: matches=%d tag_hits=%d false_alarms=%d data=%.0f\n",
- total_matches,total_tag_hits,
- total_false_alarms,
+ "total: matches=%d hash_hits=%d false_alarms=%d data=%.0f\n",
+ total_matches, total_hash_hits, total_false_alarms,
(double)stats.literal_data);
}
Matt McCutchen's Web Site / rsync / rsync.git / blobdiff