Split up the ifuncs.h file into 3 .h files.
[rsync/rsync.git] / match.c
diff --git a/match.c b/match.c
index c09a222..80619a4 100644 (file)
--- a/match.c
+++ b/match.c
@@ -1,87 +1,90 @@
 /*
-   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) 2003-2008 Wayne Davison
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 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"
+#include "inums.h"
 
-extern int verbose;
-extern int am_server;
-extern int do_progress;
 extern int checksum_seed;
-extern int inplace;
-
-typedef unsigned short tag;
+extern int append_mode;
+extern int checksum_len;
 
-#define TABLESIZE (1<<16)
-#define NULL_TAG ((size_t)-1)
+int updating_basis_file;
+char sender_file_sum[MAX_DIGEST_LEN];
 
 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;
 
-struct target {
-       tag t;
-       size_t i;
-};
+#define TRADITIONAL_TABLESIZE (1<<16)
 
-static struct target *targets;
+static uint32 tablesize;
+static int32 *hash_table;
 
-static size_t *tag_table;
-
-#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 (int)t1->t - (int)t2->t;
-}
+#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)
 {
-       size_t i;
-
-       if (!tag_table)
-               tag_table = new_array(size_t, TABLESIZE);
-
-       targets = new_array(struct target, 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);
+       static uint32 alloc_size;
+       int32 i;
+
+       /* 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;
        }
 
-       qsort(targets,s->count,sizeof(targets[0]),(int (*)())compare_targets);
+       memset(hash_table, 0xFF, tablesize * sizeof hash_table[0]);
 
-       for (i = 0; i < TABLESIZE; i++)
-               tag_table[i] = NULL_TAG;
-
-       for (i = s->count; i-- > 0; )
-               tag_table[targets[i].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;
+               }
+       }
 }
 
 
@@ -100,17 +103,20 @@ static OFF_T last_match;
  * @param i If >0, the number of a matched token.  If 0, indicates we
  * have only literal data.
  **/
-static void matched(int f,struct sum_struct *s,struct map_struct *buf,
-                   OFF_T offset,int i)
+static void matched(int f, struct sum_struct *s, struct map_struct *buf,
+                   OFF_T offset, int32 i)
 {
-       OFF_T n = offset - last_match;
-       OFF_T j;
-
-       if (verbose > 2 && i >= 0)
-               rprintf(FINFO,"match at %.0f last_match=%.0f j=%d len=%u n=%.0f\n",
-                       (double)offset,(double)last_match,i,s->sums[i].len,(double)n);
+       int32 n = (int32)(offset - last_match); /* max value: block_size (int32) */
+       int32 j;
+
+       if (DEBUG_GTE(DELTASUM, 2) && i >= 0) {
+               rprintf(FINFO,
+                       "match at %s last_match=%s j=%d len=%ld n=%ld\n",
+                       big_num(offset), big_num(last_match), i,
+                       (long)s->sums[i].len, (long)n);
+       }
 
-       send_token(f,i,buf,last_match,n,i<0?0:s->sums[i].len);
+       send_token(f, i, buf, last_match, n, i < 0 ? 0 : s->sums[i].len);
        data_transfer += n;
 
        if (i >= 0) {
@@ -119,31 +125,25 @@ static void matched(int f,struct sum_struct *s,struct map_struct *buf,
        }
 
        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);
+               int32 n1 = MIN(CHUNK_SIZE, n - j);
+               sum_update(map_ptr(buf, last_match + j, n1), n1);
        }
 
-
        if (i >= 0)
                last_match = offset + s->sums[i].len;
        else
                last_match = offset;
 
-       if (buf && do_progress) {
+       if (buf && INFO_GTE(PROGRESS, 1))
                show_progress(last_match, buf->file_size);
-
-               if (i == -1)
-                       end_progress(buf->file_size);
-       }
 }
 
 
 static void hash_search(int f,struct sum_struct *s,
                        struct map_struct *buf, OFF_T len)
 {
-       OFF_T offset, end, backup;
-       unsigned int k;
-       size_t want_i;
+       OFF_T offset, end;
+       int32 k, want_i, backup;
        char sum2[SUM_LENGTH];
        uint32 s1, s2, sum;
        int more;
@@ -153,64 +153,72 @@ static void hash_search(int f,struct sum_struct *s,
         * coding of the output to work more efficiently. */
        want_i = 0;
 
-       if (verbose > 2) {
-               rprintf(FINFO,"hash search b=%u len=%.0f\n",
-                       s->blength, (double)len);
+       if (DEBUG_GTE(DELTASUM, 2)) {
+               rprintf(FINFO, "hash search b=%ld len=%s\n",
+                       (long)s->blength, big_num(len));
        }
 
-       k = MIN(len, s->blength);
+       k = (int32)MIN(len, (OFF_T)s->blength);
 
        map = (schar *)map_ptr(buf, 0, k);
 
        sum = get_checksum1((char *)map, k);
        s1 = sum & 0xFFFF;
        s2 = sum >> 16;
-       if (verbose > 3)
-               rprintf(FINFO, "sum=%.8x k=%u\n", sum, k);
+       if (DEBUG_GTE(DELTASUM, 3))
+               rprintf(FINFO, "sum=%.8x k=%ld\n", sum, (long)k);
 
        offset = 0;
 
        end = len + 1 - s->sums[s->count-1].len;
 
-       if (verbose > 3) {
-               rprintf(FINFO, "hash search s->blength=%u len=%.0f count=%.0f\n",
-                       s->blength, (double)len, (double)s->count);
+       if (DEBUG_GTE(DELTASUM, 3)) {
+               rprintf(FINFO, "hash search s->blength=%ld len=%s count=%s\n",
+                       (long)s->blength, big_num(len), big_num(s->count));
        }
 
        do {
-               tag t = gettag2(s1,s2);
                int done_csum2 = 0;
-               size_t j = tag_table[t];
+               int32 i;
 
-               if (verbose > 4)
-                       rprintf(FINFO,"offset=%.0f sum=%08x\n",(double)offset,sum);
+               if (DEBUG_GTE(DELTASUM, 4)) {
+                       rprintf(FINFO, "offset=%s sum=%04x%04x\n",
+                               big_num(offset), s2 & 0xFFFF, s1 & 0xFFFF);
+               }
 
-               if (j == NULL_TAG)
-                       goto null_tag;
+               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);
-               tag_hits++;
+               hash_hits++;
                do {
-                       unsigned int l;
-                       size_t i = targets[j].i;
+                       int32 l;
 
                        if (sum != s->sums[i].sum1)
                                continue;
 
                        /* also make sure the two blocks are the same length */
-                       l = MIN((OFF_T)s->blength, len-offset);
+                       l = (int32)MIN((OFF_T)s->blength, len-offset);
                        if (l != s->sums[i].len)
                                continue;
 
-                       /* inplace: ensure chunk's offset is either >= our
+                       /* in-place: ensure chunk's offset is either >= our
                         * offset or that the data didn't move. */
-                       if (inplace && s->sums[i].offset < offset
+                       if (updating_basis_file && s->sums[i].offset < offset
                            && !(s->sums[i].flags & SUMFLG_SAME_OFFSET))
                                continue;
 
-                       if (verbose > 3)
-                               rprintf(FINFO,"potential match at %.0f target=%.0f %.0f sum=%08x\n",
-                                       (double)offset,(double)j,(double)i,sum);
+                       if (DEBUG_GTE(DELTASUM, 3)) {
+                               rprintf(FINFO,
+                                       "potential match at %s i=%ld sum=%08x\n",
+                                       big_num(offset), (long)i, sum);
+                       }
 
                        if (!done_csum2) {
                                map = (schar *)map_ptr(buf,offset,l);
@@ -223,12 +231,12 @@ static void hash_search(int f,struct sum_struct *s,
                                continue;
                        }
 
-                       /* If inplace is enabled, the best possible match is
+                       /* When updating in-place, the best possible match is
                         * one with an identical offset, so we prefer that over
                         * the following want_i optimization. */
-                       if (inplace) {
-                               do {
-                                       size_t i2 = targets[j].i;
+                       if (updating_basis_file) {
+                               int32 i2;
+                               for (i2 = i; i2 >= 0; i2 = s->sums[i2].chain) {
                                        if (s->sums[i2].offset != offset)
                                                continue;
                                        if (i2 != i) {
@@ -243,13 +251,13 @@ static void hash_search(int f,struct sum_struct *s,
                                         * both the sender and the receiver. */
                                        s->sums[i].flags |= SUMFLG_SAME_OFFSET;
                                        goto set_want_i;
-                               } while (++j < s->count && targets[j].t == t);
+                               }
                        }
 
                        /* we've found a match, but now check to see
                         * if want_i can hint at a better match. */
                        if (i != want_i && want_i < s->count
-                           && (!inplace || s->sums[want_i].offset >= offset
+                           && (!updating_basis_file || s->sums[want_i].offset >= offset
                             || s->sums[want_i].flags & SUMFLG_SAME_OFFSET)
                            && sum == s->sums[want_i].sum1
                            && memcmp(sum2, s->sums[want_i].sum2, s->s2length) == 0) {
@@ -262,17 +270,17 @@ static void hash_search(int f,struct sum_struct *s,
 
                        matched(f,s,buf,offset,i);
                        offset += s->sums[i].len - 1;
-                       k = MIN(s->blength, len-offset);
+                       k = (int32)MIN((OFF_T)s->blength, len-offset);
                        map = (schar *)map_ptr(buf, offset, k);
                        sum = get_checksum1((char *)map, k);
                        s1 = sum & 0xFFFF;
                        s2 = sum >> 16;
                        matches++;
                        break;
-               } while (++j < s->count && targets[j].t == t);
+               } while ((i = s->sums[i].chain) >= 0);
 
-       null_tag:
-               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;
@@ -297,14 +305,12 @@ static void hash_search(int f,struct sum_struct *s,
                   match. The 3 reads are caused by the
                   running match, the checksum update and the
                   literal send. */
-               if (backup >= CHUNK_SIZE + s->blength
-                   && end - offset > CHUNK_SIZE) {
-                       matched(f,s,buf,offset - s->blength, -2);
-               }
+               if (backup >= s->blength+CHUNK_SIZE && end-offset > CHUNK_SIZE)
+                       matched(f, s, buf, offset - s->blength, -2);
        } while (++offset < end);
 
-       matched(f,s,buf,len,-1);
-       map_ptr(buf,len-1,1);
+       matched(f, s, buf, len, -1);
+       map_ptr(buf, len-1, 1);
 }
 
 
@@ -324,55 +330,77 @@ static void hash_search(int f,struct sum_struct *s,
  **/
 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;
+       hash_hits = 0;
        matches = 0;
        data_transfer = 0;
 
        sum_init(checksum_seed);
 
-       if (len > 0 && s->count>0) {
+       if (append_mode > 0) {
+               if (append_mode == 2) {
+                       OFF_T j = 0;
+                       for (j = CHUNK_SIZE; j < s->flength; j += CHUNK_SIZE) {
+                               if (buf && INFO_GTE(PROGRESS, 1))
+                                       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 && INFO_GTE(PROGRESS, 1))
+                                       show_progress(last_match, buf->file_size);
+                               sum_update(map_ptr(buf, last_match, n), n);
+                       }
+               }
+               last_match = s->flength;
+               s->count = 0;
+       }
+
+       if (len > 0 && s->count > 0) {
                build_hash_table(s);
 
-               if (verbose > 2)
+               if (DEBUG_GTE(DELTASUM, 2))
                        rprintf(FINFO,"built hash table\n");
 
-               hash_search(f,s,buf,len);
+               hash_search(f, s, buf, len);
 
-               if (verbose > 2)
+               if (DEBUG_GTE(DELTASUM, 2))
                        rprintf(FINFO,"done hash search\n");
        } else {
                OFF_T j;
                /* by doing this in pieces we avoid too many seeks */
-               for (j = 0; j < len-CHUNK_SIZE; j += CHUNK_SIZE) {
-                       int n1 = MIN(CHUNK_SIZE,(len-CHUNK_SIZE)-j);
-                       matched(f,s,buf,j+n1,-2);
-               }
-               matched(f,s,buf,len,-1);
+               for (j = last_match + CHUNK_SIZE; j < len; j += CHUNK_SIZE)
+                       matched(f, s, buf, j, -2);
+               matched(f, s, buf, len, -1);
        }
 
-       sum_end(file_sum);
-       /* If we had a read error, send a bad checksum. */
-       if (buf && buf->status != 0)
-               file_sum[0]++;
+       if (sum_end(sender_file_sum) != checksum_len)
+               overflow_exit("checksum_len"); /* Impossible... */
+
+       /* If we had a read error, send a bad checksum.  We use all bits
+        * off as long as the checksum doesn't happen to be that, in
+        * which case we turn the last 0 bit into a 1. */
+       if (buf && buf->status != 0) {
+               int i;
+               for (i = 0; i < checksum_len && sender_file_sum[i] == 0; i++) {}
+               memset(sender_file_sum, 0, checksum_len);
+               if (i == checksum_len)
+                       sender_file_sum[i-1]++;
+       }
 
-       if (verbose > 2)
+       if (DEBUG_GTE(DELTASUM, 2))
                rprintf(FINFO,"sending file_sum\n");
-       write_buf(f,file_sum,MD4_SUM_LENGTH);
+       write_buf(f, sender_file_sum, checksum_len);
 
-       if (targets) {
-               free(targets);
-               targets=NULL;
+       if (DEBUG_GTE(DELTASUM, 2)) {
+               rprintf(FINFO, "false_alarms=%d hash_hits=%d matches=%d\n",
+                       false_alarms, hash_hits, matches);
        }
 
-       if (verbose > 2)
-               rprintf(FINFO, "false_alarms=%d tag_hits=%d matches=%d\n",
-                       false_alarms, tag_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;
@@ -380,12 +408,11 @@ void match_sums(int f, struct sum_struct *s, struct map_struct *buf, OFF_T len)
 
 void match_report(void)
 {
-       if (verbose <= 1)
+       if (!DEBUG_GTE(DELTASUM, 1))
                return;
 
        rprintf(FINFO,
-               "total: matches=%d  tag_hits=%d  false_alarms=%d data=%.0f\n",
-               total_matches,total_tag_hits,
-               total_false_alarms,
-               (double)stats.literal_data);
+               "total: matches=%d  hash_hits=%d  false_alarms=%d data=%s\n",
+               total_matches, total_hash_hits, total_false_alarms,
+               big_num(stats.literal_data));
 }