My version of Mark Curtis's --inplace option.

[rsync/rsync.git] / match.c

diff --git a/match.c b/match.c
index d731aae..f3858e5 100644 (file)
--- a/match.c
+++ b/match.c
@@ -23,6 +23,7 @@ extern int verbose;
 extern int am_server;
 extern int do_progress;
 extern int checksum_seed;
+extern int inplace;
 
 typedef unsigned short tag;
 
@@ -200,6 +201,12 @@ static void hash_search(int f,struct sum_struct *s,
                        if (l != s->sums[i].len)
                                continue;
 
+                       /* inplace: ensure chunk's offset is either >= our
+                        * offset or that the data didn't move. */
+                       if (inplace && 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);
@@ -215,15 +222,41 @@ static void hash_search(int f,struct sum_struct *s,
                                continue;
                        }
 
+                       /* If inplace is enabled, 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 (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;
+                                       }
+                                       /* This chunk was at the same offset on
+                                        * 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
+                            || s->sums[want_i].flags & SUMFLG_SAME_OFFSET)
                            && sum == s->sums[want_i].sum1
                            && memcmp(sum2, s->sums[want_i].sum2, s->s2length) == 0) {
                                /* we've found an adjacent match - the RLL coder
                                 * will be happy */
                                i = want_i;
                        }
+                   set_want_i:
                        want_i = i + 1;
 
                        matched(f,s,buf,offset,i);