Switch over to Matt's idea of using FLAG_OWNED_BY_US.

[rsync.git] / match.c

diff --git a/match.c b/match.c
index 45c512cf87006d904e5258409403a0fdd1c812aa..658d7866797d412d5a8e895cefa65ed064784dab 100644 (file)
--- a/match.c
+++ b/match.c
@@ -90,8 +90,7 @@ static void build_hash_table(struct sum_struct *s)
 static OFF_T last_match;
 
 
-/**
- * Transmit a literal and/or match token.
+/* Transmit a literal and/or match token.
  *
  * This delightfully-named function is called either when we find a
  * match and need to transmit all the unmatched data leading up to it,
@@ -99,9 +98,9 @@ static OFF_T last_match;
  * transmit it.  As a result of this second case, it is called even if
  * we have not matched at all!
  *
- * @param i If >0, the number of a matched token.  If 0, indicates we
- * have only literal data.
- **/
+ * If i >= 0, the number of a matched token.  If < 0, indicates we have
+ * only literal data.  A -1 will send a 0-token-int too, and a -2 sends
+ * only literal data, w/o any token-int. */
 static void matched(int f, struct sum_struct *s, struct map_struct *buf,
                    OFF_T offset, int32 i)
 {
@@ -141,8 +140,8 @@ static void matched(int f, struct sum_struct *s, struct map_struct *buf,
 static void hash_search(int f,struct sum_struct *s,
                        struct map_struct *buf, OFF_T len)
 {
-       OFF_T offset, end;
-       int32 k, want_i, backup;
+       OFF_T offset, aligned_offset, end;
+       int32 k, want_i, aligned_i, backup;
        char sum2[SUM_LENGTH];
        uint32 s1, s2, sum;
        int more;
@@ -167,7 +166,7 @@ static void hash_search(int f,struct sum_struct *s,
        if (verbose > 3)
                rprintf(FINFO, "sum=%.8x k=%ld\n", sum, (long)k);
 
-       offset = 0;
+       offset = aligned_offset = aligned_i = 0;
 
        end = len + 1 - s->sums[s->count-1].len;
 
@@ -232,27 +231,28 @@ static void hash_search(int f,struct sum_struct *s,
 
                        /* When updating in-place, the best possible match is
                         * one with an identical offset, so we prefer that over
-                        * the following want_i optimization. */
+                        * the adjacent want_i optimization. */
                        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) {
-                                               if (sum != s->sums[i2].sum1)
-                                                       break;
-                                               if (memcmp(sum2, s->sums[i2].sum2,
-                                                          s->s2length) != 0)
-                                                       break;
-                                               i = i2;
+                               /* All the generator's chunks start at blength boundaries. */
+                               while (aligned_offset < offset) {
+                                       aligned_offset += s->blength;
+                                       aligned_i++;
+                               }
+                               if (offset == aligned_offset) {
+                                       if (i != aligned_i) {
+                                               if (sum != s->sums[aligned_i].sum1
+                                                || l != s->sums[aligned_i].len
+                                                || memcmp(sum2, s->sums[aligned_i].sum2, s->s2length) != 0)
+                                                       goto check_want_i;
+                                               i = aligned_i;
                                        }
-                                       /* This chunk was at the same offset on
-                                        * both the sender and the receiver. */
+                                       /* This identical chunk is in the same spot in the old and new file. */
                                        s->sums[i].flags |= SUMFLG_SAME_OFFSET;
-                                       goto set_want_i;
+                                       want_i = i;
                                }
                        }
 
+                 check_want_i:
                        /* 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
@@ -264,7 +264,6 @@ static void hash_search(int f,struct sum_struct *s,
                                 * will be happy */
                                i = want_i;
                        }
-                   set_want_i:
                        want_i = i + 1;
 
                        matched(f,s,buf,offset,i);