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/*
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.
*/
#include "rsync.h"
extern int csum_length;
extern int verbose;
extern int am_server;
extern int remote_version;
typedef unsigned short tag;
#define TABLESIZE (1<<16)
#define NULL_TAG ((tag)-1)
static int false_alarms;
static int tag_hits;
static int matches;
static int data_transfer;
static int total_false_alarms=0;
static int total_tag_hits=0;
static int total_matches=0;
static int total_data_transfer=0;
struct target {
tag t;
int i;
};
static struct target *targets=NULL;
static tag *tag_table = NULL;
#define gettag2(s1,s2) (((s1) + (s2)) & 0xFFFF)
#define gettag(sum) gettag2((sum)&0xFFFF,(sum)>>16)
static int compare_targets(struct target *t1,struct target *t2)
{
return(t1->t - t2->t);
}
static void build_hash_table(struct sum_struct *s)
{
int i;
if (!tag_table)
tag_table = (tag *)malloc(sizeof(tag)*TABLESIZE);
targets = (struct target *)malloc(sizeof(targets[0])*s->count);
if (!tag_table || !targets)
out_of_memory("build_hash_table");
for (i=0;i<s->count;i++) {
targets[i].i = i;
targets[i].t = gettag(s->sums[i].sum1);
}
qsort(targets,s->count,sizeof(targets[0]),(int (*)())compare_targets);
for (i=0;i<TABLESIZE;i++)
tag_table[i] = NULL_TAG;
for (i=s->count-1;i>=0;i--) {
tag_table[targets[i].t] = i;
}
}
static off_t last_match;
static void matched(int f,struct sum_struct *s,struct map_struct *buf,
int offset,int i)
{
int n = offset - last_match;
int j;
if (verbose > 2)
if (i != -1)
fprintf(FERROR,"match at %d last_match=%d j=%d len=%d n=%d\n",
(int)offset,(int)last_match,i,(int)s->sums[i].len,n);
send_token(f,i,buf,last_match,n,i==-1?0:s->sums[i].len);
data_transfer += n;
if (n > 0)
write_flush(f);
if (i != -1)
n += s->sums[i].len;
for (j=0;j<n;j+=CHUNK_SIZE) {
int n1 = MIN(CHUNK_SIZE,n-j);
sum_update(map_ptr(buf,last_match+j,n1),n1);
}
if (i != -1)
last_match = offset + s->sums[i].len;
}
static void hash_search(int f,struct sum_struct *s,
struct map_struct *buf,off_t len)
{
int offset,j,k;
int end;
char sum2[SUM_LENGTH];
uint32 s1, s2, sum;
signed char *map;
if (verbose > 2)
fprintf(FERROR,"hash search b=%d len=%d\n",s->n,(int)len);
k = MIN(len, s->n);
map = (signed char *)map_ptr(buf,0,k);
sum = get_checksum1((char *)map, k);
s1 = sum & 0xFFFF;
s2 = sum >> 16;
if (verbose > 3)
fprintf(FERROR, "sum=%.8x k=%d\n", sum, k);
offset = 0;
end = len + 1 - s->sums[s->count-1].len;
if (verbose > 3)
fprintf(FERROR,"hash search s->n=%d len=%d count=%d\n",
s->n,(int)len,s->count);
do {
tag t = gettag2(s1,s2);
j = tag_table[t];
if (verbose > 4)
fprintf(FERROR,"offset=%d sum=%08x\n",
offset,sum);
if (j != NULL_TAG) {
int done_csum2 = 0;
sum = (s1 & 0xffff) | (s2 << 16);
tag_hits++;
do {
int i = targets[j].i;
if (sum == s->sums[i].sum1) {
if (verbose > 3)
fprintf(FERROR,"potential match at %d target=%d %d sum=%08x\n",
offset,j,i,sum);
if (!done_csum2) {
int l = MIN(s->n,len-offset);
map = (signed char *)map_ptr(buf,offset,l);
get_checksum2((char *)map,l,sum2);
done_csum2 = 1;
}
if (memcmp(sum2,s->sums[i].sum2,csum_length) == 0) {
matched(f,s,buf,offset,i);
offset += s->sums[i].len - 1;
k = MIN((len-offset), s->n);
map = (signed char *)map_ptr(buf,offset,k);
sum = get_checksum1((char *)map, k);
s1 = sum & 0xFFFF;
s2 = sum >> 16;
++matches;
break;
} else {
false_alarms++;
}
}
j++;
} while (j<s->count && targets[j].t == t);
}
/* Trim off the first byte from the checksum */
map = (signed char *)map_ptr(buf,offset,k+1);
s1 -= map[0] + CHAR_OFFSET;
s2 -= k * (map[0]+CHAR_OFFSET);
/* Add on the next byte (if there is one) to the checksum */
if (k < (len-offset)) {
s1 += (map[k]+CHAR_OFFSET);
s2 += s1;
} else {
--k;
}
} while (++offset < end);
matched(f,s,buf,len,-1);
map_ptr(buf,len-1,1);
}
void match_sums(int f,struct sum_struct *s,struct map_struct *buf,off_t len)
{
char file_sum[MD4_SUM_LENGTH];
last_match = 0;
false_alarms = 0;
tag_hits = 0;
matches=0;
data_transfer=0;
sum_init();
if (len > 0 && s->count>0) {
build_hash_table(s);
if (verbose > 2)
fprintf(FERROR,"built hash table\n");
hash_search(f,s,buf,len);
if (verbose > 2)
fprintf(FERROR,"done hash search\n");
} else {
matched(f,s,buf,len,-1);
}
sum_end(file_sum);
if (remote_version >= 14) {
if (verbose > 2)
fprintf(FERROR,"sending file_sum\n");
write_buf(f,file_sum,MD4_SUM_LENGTH);
}
if (targets) {
free(targets);
targets=NULL;
}
if (verbose > 2)
fprintf(FERROR, "false_alarms=%d tag_hits=%d matches=%d\n",
false_alarms, tag_hits, matches);
total_tag_hits += tag_hits;
total_false_alarms += false_alarms;
total_matches += matches;
total_data_transfer += data_transfer;
}
void match_report(void)
{
if (verbose <= 1)
return;
fprintf(FINFO,
"total: matches=%d tag_hits=%d false_alarms=%d data=%d\n",
total_matches,total_tag_hits,
total_false_alarms,total_data_transfer);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.