2 Copyright (C) Andrew Tridgell 1996
3 Copyright (C) Paul Mackerras 1996
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 extern int csum_length;
27 extern int remote_version;
29 typedef unsigned short tag;
31 #define TABLESIZE (1<<16)
32 #define NULL_TAG ((tag)-1)
34 static int false_alarms;
37 static int data_transfer;
39 static int total_false_alarms=0;
40 static int total_tag_hits=0;
41 static int total_matches=0;
42 static int total_data_transfer=0;
50 static struct target *targets=NULL;
52 static tag *tag_table = NULL;
54 #define gettag2(s1,s2) (((s1) + (s2)) & 0xFFFF)
55 #define gettag(sum) gettag2((sum)&0xFFFF,(sum)>>16)
57 static int compare_targets(struct target *t1,struct target *t2)
59 return(t1->t - t2->t);
63 static void build_hash_table(struct sum_struct *s)
68 tag_table = (tag *)malloc(sizeof(tag)*TABLESIZE);
70 targets = (struct target *)malloc(sizeof(targets[0])*s->count);
71 if (!tag_table || !targets)
72 out_of_memory("build_hash_table");
74 for (i=0;i<s->count;i++) {
76 targets[i].t = gettag(s->sums[i].sum1);
79 qsort(targets,s->count,sizeof(targets[0]),(int (*)())compare_targets);
81 for (i=0;i<TABLESIZE;i++)
82 tag_table[i] = NULL_TAG;
84 for (i=s->count-1;i>=0;i--) {
85 tag_table[targets[i].t] = i;
90 static off_t last_match;
93 static void matched(int f,struct sum_struct *s,struct map_struct *buf,
96 int n = offset - last_match;
101 fprintf(FERROR,"match at %d last_match=%d j=%d len=%d n=%d\n",
102 (int)offset,(int)last_match,i,(int)s->sums[i].len,n);
104 send_token(f,i,buf,last_match,n,i==-1?0:s->sums[i].len);
113 for (j=0;j<n;j+=CHUNK_SIZE) {
114 int n1 = MIN(CHUNK_SIZE,n-j);
115 sum_update(map_ptr(buf,last_match+j,n1),n1);
120 last_match = offset + s->sums[i].len;
125 static void hash_search(int f,struct sum_struct *s,
126 struct map_struct *buf,off_t len)
130 char sum2[SUM_LENGTH];
135 fprintf(FERROR,"hash search b=%d len=%d\n",s->n,(int)len);
139 map = (signed char *)map_ptr(buf,0,k);
141 sum = get_checksum1((char *)map, k);
145 fprintf(FERROR, "sum=%.8x k=%d\n", sum, k);
149 end = len + 1 - s->sums[s->count-1].len;
152 fprintf(FERROR,"hash search s->n=%d len=%d count=%d\n",
153 s->n,(int)len,s->count);
156 tag t = gettag2(s1,s2);
159 fprintf(FERROR,"offset=%d sum=%08x\n",
165 sum = (s1 & 0xffff) | (s2 << 16);
168 int i = targets[j].i;
170 if (sum == s->sums[i].sum1) {
172 fprintf(FERROR,"potential match at %d target=%d %d sum=%08x\n",
176 int l = MIN(s->n,len-offset);
177 map = (signed char *)map_ptr(buf,offset,l);
178 get_checksum2((char *)map,l,sum2);
181 if (memcmp(sum2,s->sums[i].sum2,csum_length) == 0) {
182 matched(f,s,buf,offset,i);
183 offset += s->sums[i].len - 1;
184 k = MIN((len-offset), s->n);
185 map = (signed char *)map_ptr(buf,offset,k);
186 sum = get_checksum1((char *)map, k);
196 } while (j<s->count && targets[j].t == t);
199 /* Trim off the first byte from the checksum */
200 map = (signed char *)map_ptr(buf,offset,k+1);
201 s1 -= map[0] + CHAR_OFFSET;
202 s2 -= k * (map[0]+CHAR_OFFSET);
204 /* Add on the next byte (if there is one) to the checksum */
205 if (k < (len-offset)) {
206 s1 += (map[k]+CHAR_OFFSET);
212 } while (++offset < end);
214 matched(f,s,buf,len,-1);
215 map_ptr(buf,len-1,1);
219 void match_sums(int f,struct sum_struct *s,struct map_struct *buf,off_t len)
221 char file_sum[MD4_SUM_LENGTH];
231 if (len > 0 && s->count>0) {
235 fprintf(FERROR,"built hash table\n");
237 hash_search(f,s,buf,len);
240 fprintf(FERROR,"done hash search\n");
242 matched(f,s,buf,len,-1);
247 if (remote_version >= 14) {
249 fprintf(FERROR,"sending file_sum\n");
250 write_buf(f,file_sum,MD4_SUM_LENGTH);
259 fprintf(FERROR, "false_alarms=%d tag_hits=%d matches=%d\n",
260 false_alarms, tag_hits, matches);
262 total_tag_hits += tag_hits;
263 total_false_alarms += false_alarms;
264 total_matches += matches;
265 total_data_transfer += data_transfer;
268 void match_report(void)
274 "total: matches=%d tag_hits=%d false_alarms=%d data=%d\n",
275 total_matches,total_tag_hits,
276 total_false_alarms,total_data_transfer);