Plug diff leaks.

It is a bit embarrassing that it took this long for a fix since the
problem was first reported on Aug 13th.

    Message-ID: <87y876gl1r.wl@mail2.atmark-techno.com>
    From: Yasushi SHOJI <yashi@atmark-techno.com>
    Newsgroups: gmane.comp.version-control.git
    Subject: [patch] possible memory leak in diff.c::diff_free_filepair()
    Date: Sat, 13 Aug 2005 19:58:56 +0900

This time I used valgrind to make sure that it does not overeagerly
discard memory that is still being used.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/diff-tree.c b/diff-tree.c
index fc87902..e8f5d1b 100644 (file)
--- a/diff-tree.c
+++ b/diff-tree.c
@@ -370,6 +370,7 @@ static int diff_tree_commit(const unsigned char *commit, const char *name)
                }
                offset += 48;
        }
+       free(buf);
        return 0;
 }
 

diff --git a/diff.c b/diff.c
index 05a0663..d8d20c2 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -762,7 +762,8 @@ struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
        dp->status = 0;
        dp->source_stays = 0;
        dp->broken_pair = 0;
-       diff_q(queue, dp);
+       if (queue)
+               diff_q(queue, dp);
        return dp;
 }
 
@@ -770,6 +771,8 @@ void diff_free_filepair(struct diff_filepair *p)
 {
        diff_free_filespec_data(p->one);
        diff_free_filespec_data(p->two);
+       free(p->one);
+       free(p->two);
        free(p);
 }
 

diff --git a/diffcore-rename.c b/diffcore-rename.c
index dbc8522..092cf68 100644 (file)
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -47,7 +47,8 @@ static struct diff_rename_dst *locate_rename_dst(struct diff_filespec *two,
        if (first < rename_dst_nr)
                memmove(rename_dst + first + 1, rename_dst + first,
                        (rename_dst_nr - first - 1) * sizeof(*rename_dst));
-       rename_dst[first].two = two;
+       rename_dst[first].two = alloc_filespec(two->path);
+       fill_filespec(rename_dst[first].two, two->sha1, two->mode);
        rename_dst[first].pair = NULL;
        return &(rename_dst[first]);
 }
@@ -201,8 +202,7 @@ static int estimate_similarity(struct diff_filespec *src,
        return score;
 }
 
-static void record_rename_pair(struct diff_queue_struct *renq,
-                              int dst_index, int src_index, int score)
+static void record_rename_pair(int dst_index, int src_index, int score)
 {
        struct diff_filespec *one, *two, *src, *dst;
        struct diff_filepair *dp;
@@ -218,7 +218,7 @@ static void record_rename_pair(struct diff_queue_struct *renq,
        two = alloc_filespec(dst->path);
        fill_filespec(two, dst->sha1, dst->mode);
 
-       dp = diff_queue(renq, one, two);
+       dp = diff_queue(NULL, one, two);
        dp->score = score;
        dp->source_stays = rename_src[src_index].src_path_left;
        rename_dst[dst_index].pair = dp;
@@ -252,15 +252,14 @@ static int compute_stays(struct diff_queue_struct *q,
 void diffcore_rename(int detect_rename, int minimum_score)
 {
        struct diff_queue_struct *q = &diff_queued_diff;
-       struct diff_queue_struct renq, outq;
+       struct diff_queue_struct outq;
        struct diff_score *mx;
-       int i, j;
+       int i, j, rename_count;
        int num_create, num_src, dst_cnt;
 
        if (!minimum_score)
                minimum_score = DEFAULT_RENAME_SCORE;
-       renq.queue = NULL;
-       renq.nr = renq.alloc = 0;
+       rename_count = 0;
 
        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
@@ -292,19 +291,19 @@ void diffcore_rename(int detect_rename, int minimum_score)
                        struct diff_filespec *one = rename_src[j].one;
                        if (!is_exact_match(one, two))
                                continue;
-                       record_rename_pair(&renq, i, j, MAX_SCORE);
+                       record_rename_pair(i, j, MAX_SCORE);
+                       rename_count++;
                        break; /* we are done with this entry */
                }
        }
-       diff_debug_queue("done detecting exact", &renq);
 
        /* Have we run out the created file pool?  If so we can avoid
         * doing the delta matrix altogether.
         */
-       if (renq.nr == rename_dst_nr)
+       if (rename_count == rename_dst_nr)
                goto cleanup;
 
-       num_create = (rename_dst_nr - renq.nr);
+       num_create = (rename_dst_nr - rename_count);
        num_src = rename_src_nr;
        mx = xmalloc(sizeof(*mx) * num_create * num_src);
        for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
@@ -330,14 +329,14 @@ void diffcore_rename(int detect_rename, int minimum_score)
                        continue; /* already done, either exact or fuzzy. */
                if (mx[i].score < minimum_score)
                        break; /* there is no more usable pair. */
-               record_rename_pair(&renq, mx[i].dst, mx[i].src, mx[i].score);
+               record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
+               rename_count++;
        }
        free(mx);
-       diff_debug_queue("done detecting fuzzy", &renq);
 
  cleanup:
        /* At this point, we have found some renames and copies and they
-        * are kept in renq.  The original list is still in *q.
+        * are recorded in rename_dst.  The original list is still in *q.
         */
        outq.queue = NULL;
        outq.nr = outq.alloc = 0;
@@ -372,9 +371,9 @@ void diffcore_rename(int detect_rename, int minimum_score)
                         *
                         * (1) this is a broken delete and the counterpart
                         *     broken create remains in the output; or
-                        * (2) this is not a broken delete, and renq does
-                        *     not have a rename/copy to move p->one->path
-                        *     out.
+                        * (2) this is not a broken delete, and rename_dst
+                        *     does not have a rename/copy to move p->one->path
+                        *     out of existence.
                         *
                         * Otherwise, the counterpart broken create
                         * has been turned into a rename-edit; or
@@ -390,11 +389,16 @@ void diffcore_rename(int detect_rename, int minimum_score)
                                        pair_to_free = p;
                        }
                        else {
-                               for (j = 0; j < renq.nr; j++)
-                                       if (!strcmp(renq.queue[j]->one->path,
-                                                   p->one->path))
-                                               break;
-                               if (j < renq.nr)
+                               for (j = 0; j < rename_dst_nr; j++) {
+                                       if (!rename_dst[j].pair)
+                                               continue;
+                                       if (strcmp(rename_dst[j].pair->
+                                                  one->path,
+                                                  p->one->path))
+                                               continue;
+                                       break;
+                               }
+                               if (j < rename_dst_nr)
                                        /* this path remains */
                                        pair_to_free = p;
                        }
@@ -416,7 +420,6 @@ void diffcore_rename(int detect_rename, int minimum_score)
        }
        diff_debug_queue("done copying original", &outq);
 
-       free(renq.queue);
        free(q->queue);
        *q = outq;
        diff_debug_queue("done collapsing", q);
@@ -438,6 +441,11 @@ void diffcore_rename(int detect_rename, int minimum_score)
                }
        }
 
+       for (i = 0; i < rename_dst_nr; i++) {
+               diff_free_filespec_data(rename_dst[i].two);
+               free(rename_dst[i].two);
+       }
+
        free(rename_dst);
        rename_dst = NULL;
        rename_dst_nr = rename_dst_alloc = 0;