*
* Copyright (C) 1996 Andrew Tridgell
* Copyright (C) 1996 Paul Mackerras
- * Copyright (C) 2003-2007 Wayne Davison
+ * Copyright (C) 2003-2008 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.
+ * 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
* 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.
+ * with this program; if not, visit the http://fsf.org website.
*/
#include "rsync.h"
extern struct stats stats;
-#define TABLESIZE (1<<16)
+#define TRADITIONAL_TABLESIZE (1<<16)
+static uint32 tablesize;
static int32 *hash_table;
#define SUM2HASH2(s1,s2) (((s1) + (s2)) & 0xFFFF)
#define SUM2HASH(sum) SUM2HASH2((sum)&0xFFFF,(sum)>>16)
+#define BIG_SUM2HASH(sum) ((sum)%tablesize)
+
static void build_hash_table(struct sum_struct *s)
{
+ static uint32 alloc_size;
int32 i;
- if (!hash_table) {
- hash_table = new_array(int32, TABLESIZE);
+ /* Dynamically calculate the hash table size so that the hash load
+ * for big files is about 80%. A number greater than the traditional
+ * size must be odd or s2 will not be able to span the entire set. */
+ tablesize = (uint32)(s->count/8) * 10 + 11;
+ if (tablesize < TRADITIONAL_TABLESIZE)
+ tablesize = TRADITIONAL_TABLESIZE;
+ if (tablesize > alloc_size || tablesize < alloc_size - 16*1024) {
+ if (hash_table)
+ free(hash_table);
+ hash_table = new_array(int32, tablesize);
if (!hash_table)
out_of_memory("build_hash_table");
+ alloc_size = tablesize;
}
- 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);
- s->sums[i].chain = hash_table[t];
- hash_table[t] = i;
+ if (tablesize == TRADITIONAL_TABLESIZE) {
+ for (i = 0; i < s->count; i++) {
+ uint32 t = SUM2HASH(s->sums[i].sum1);
+ s->sums[i].chain = hash_table[t];
+ hash_table[t] = i;
+ }
+ } else {
+ for (i = 0; i < s->count; i++) {
+ uint32 t = BIG_SUM2HASH(s->sums[i].sum1);
+ s->sums[i].chain = hash_table[t];
+ hash_table[t] = i;
+ }
}
}
(double)offset, s2 & 0xFFFF, s1 & 0xFFFF);
}
- i = hash_table[SUM2HASH2(s1,s2)];
- if (i < 0)
- goto null_hash;
+ if (tablesize == TRADITIONAL_TABLESIZE) {
+ if ((i = hash_table[SUM2HASH2(s1,s2)]) < 0)
+ goto null_hash;
+ sum = (s1 & 0xffff) | (s2 << 16);
+ } else {
+ sum = (s1 & 0xffff) | (s2 << 16);
+ if ((i = hash_table[BIG_SUM2HASH(sum)]) < 0)
+ goto null_hash;
+ }
- sum = (s1 & 0xffff) | (s2 << 16);
hash_hits++;
do {
int32 l;
sum_init(checksum_seed);
if (append_mode > 0) {
- 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;
+ 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;
}