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authorJunio C Hamano <gitster@pobox.com>2008-09-02 17:47:13 -0700
committerJunio C Hamano <gitster@pobox.com>2008-09-02 17:47:13 -0700
commit01914577ed42498d9e268684949d699e0272e964 (patch)
treea0405b854b76eeb5b90b7f13ebd3607a655fb2cf /revision.c
parent53b543ab8218cede7fb9383298c00dcef663692c (diff)
parente910ce30e41ae4ddc20a64661e8cf2702433e5db (diff)
downloadgit-01914577ed42498d9e268684949d699e0272e964.tar.gz
Merge branch 'tr/filter-branch'
* tr/filter-branch: revision --simplify-merges: make it a no-op without pathspec revision --simplify-merges: do not leave commits unprocessed revision --simplify-merges: use decoration instead of commit->util field Documentation: rev-list-options: move --simplify-merges documentation filter-branch: use --simplify-merges filter-branch: fix ref rewriting with --subdirectory-filter filter-branch: Extend test to show rewriting bug Topo-sort before --simplify-merges revision traversal: show full history with merge simplification revision.c: whitespace fix
Diffstat (limited to 'revision.c')
-rw-r--r--revision.c202
1 files changed, 181 insertions, 21 deletions
diff --git a/revision.c b/revision.c
index 36291b6b86..bcbc7bd7e4 100644
--- a/revision.c
+++ b/revision.c
@@ -489,7 +489,7 @@ static int add_parents_to_list(struct rev_info *revs, struct commit *commit,
p->object.flags |= SEEN;
insert_by_date_cached(p, list, cached_base, cache_ptr);
}
- if(revs->first_parent_only)
+ if (revs->first_parent_only)
break;
}
return 0;
@@ -1041,6 +1041,11 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
} else if (!strcmp(arg, "--topo-order")) {
revs->lifo = 1;
revs->topo_order = 1;
+ } else if (!strcmp(arg, "--simplify-merges")) {
+ revs->simplify_merges = 1;
+ revs->rewrite_parents = 1;
+ revs->simplify_history = 0;
+ revs->limited = 1;
} else if (!strcmp(arg, "--date-order")) {
revs->lifo = 0;
revs->topo_order = 1;
@@ -1368,6 +1373,179 @@ static void add_child(struct rev_info *revs, struct commit *parent, struct commi
l->next = add_decoration(&revs->children, &parent->object, l);
}
+static int remove_duplicate_parents(struct commit *commit)
+{
+ struct commit_list **pp, *p;
+ int surviving_parents;
+
+ /* Examine existing parents while marking ones we have seen... */
+ pp = &commit->parents;
+ while ((p = *pp) != NULL) {
+ struct commit *parent = p->item;
+ if (parent->object.flags & TMP_MARK) {
+ *pp = p->next;
+ continue;
+ }
+ parent->object.flags |= TMP_MARK;
+ pp = &p->next;
+ }
+ /* count them while clearing the temporary mark */
+ surviving_parents = 0;
+ for (p = commit->parents; p; p = p->next) {
+ p->item->object.flags &= ~TMP_MARK;
+ surviving_parents++;
+ }
+ return surviving_parents;
+}
+
+struct merge_simplify_state {
+ struct commit *simplified;
+};
+
+static struct merge_simplify_state *locate_simplify_state(struct rev_info *revs, struct commit *commit)
+{
+ struct merge_simplify_state *st;
+
+ st = lookup_decoration(&revs->merge_simplification, &commit->object);
+ if (!st) {
+ st = xcalloc(1, sizeof(*st));
+ add_decoration(&revs->merge_simplification, &commit->object, st);
+ }
+ return st;
+}
+
+static struct commit_list **simplify_one(struct rev_info *revs, struct commit *commit, struct commit_list **tail)
+{
+ struct commit_list *p;
+ struct merge_simplify_state *st, *pst;
+ int cnt;
+
+ st = locate_simplify_state(revs, commit);
+
+ /*
+ * Have we handled this one?
+ */
+ if (st->simplified)
+ return tail;
+
+ /*
+ * An UNINTERESTING commit simplifies to itself, so does a
+ * root commit. We do not rewrite parents of such commit
+ * anyway.
+ */
+ if ((commit->object.flags & UNINTERESTING) || !commit->parents) {
+ st->simplified = commit;
+ return tail;
+ }
+
+ /*
+ * Do we know what commit all of our parents should be rewritten to?
+ * Otherwise we are not ready to rewrite this one yet.
+ */
+ for (cnt = 0, p = commit->parents; p; p = p->next) {
+ pst = locate_simplify_state(revs, p->item);
+ if (!pst->simplified) {
+ tail = &commit_list_insert(p->item, tail)->next;
+ cnt++;
+ }
+ }
+ if (cnt) {
+ tail = &commit_list_insert(commit, tail)->next;
+ return tail;
+ }
+
+ /*
+ * Rewrite our list of parents.
+ */
+ for (p = commit->parents; p; p = p->next) {
+ pst = locate_simplify_state(revs, p->item);
+ p->item = pst->simplified;
+ }
+ cnt = remove_duplicate_parents(commit);
+
+ /*
+ * It is possible that we are a merge and one side branch
+ * does not have any commit that touches the given paths;
+ * in such a case, the immediate parents will be rewritten
+ * to different commits.
+ *
+ * o----X X: the commit we are looking at;
+ * / / o: a commit that touches the paths;
+ * ---o----'
+ *
+ * Further reduce the parents by removing redundant parents.
+ */
+ if (1 < cnt) {
+ struct commit_list *h = reduce_heads(commit->parents);
+ cnt = commit_list_count(h);
+ free_commit_list(commit->parents);
+ commit->parents = h;
+ }
+
+ /*
+ * A commit simplifies to itself if it is a root, if it is
+ * UNINTERESTING, if it touches the given paths, or if it is a
+ * merge and its parents simplifies to more than one commits
+ * (the first two cases are already handled at the beginning of
+ * this function).
+ *
+ * Otherwise, it simplifies to what its sole parent simplifies to.
+ */
+ if (!cnt ||
+ (commit->object.flags & UNINTERESTING) ||
+ !(commit->object.flags & TREESAME) ||
+ (1 < cnt))
+ st->simplified = commit;
+ else {
+ pst = locate_simplify_state(revs, commit->parents->item);
+ st->simplified = pst->simplified;
+ }
+ return tail;
+}
+
+static void simplify_merges(struct rev_info *revs)
+{
+ struct commit_list *list;
+ struct commit_list *yet_to_do, **tail;
+
+ if (!revs->topo_order)
+ sort_in_topological_order(&revs->commits, revs->lifo);
+ if (!revs->prune)
+ return;
+
+ /* feed the list reversed */
+ yet_to_do = NULL;
+ for (list = revs->commits; list; list = list->next)
+ commit_list_insert(list->item, &yet_to_do);
+ while (yet_to_do) {
+ list = yet_to_do;
+ yet_to_do = NULL;
+ tail = &yet_to_do;
+ while (list) {
+ struct commit *commit = list->item;
+ struct commit_list *next = list->next;
+ free(list);
+ list = next;
+ tail = simplify_one(revs, commit, tail);
+ }
+ }
+
+ /* clean up the result, removing the simplified ones */
+ list = revs->commits;
+ revs->commits = NULL;
+ tail = &revs->commits;
+ while (list) {
+ struct commit *commit = list->item;
+ struct commit_list *next = list->next;
+ struct merge_simplify_state *st;
+ free(list);
+ list = next;
+ st = locate_simplify_state(revs, commit);
+ if (st->simplified == commit)
+ tail = &commit_list_insert(commit, tail)->next;
+ }
+}
+
static void set_children(struct rev_info *revs)
{
struct commit_list *l;
@@ -1408,6 +1586,8 @@ int prepare_revision_walk(struct rev_info *revs)
return -1;
if (revs->topo_order)
sort_in_topological_order(&revs->commits, revs->lifo);
+ if (revs->simplify_merges)
+ simplify_merges(revs);
if (revs->children.name)
set_children(revs);
return 0;
@@ -1440,26 +1620,6 @@ static enum rewrite_result rewrite_one(struct rev_info *revs, struct commit **pp
}
}
-static void remove_duplicate_parents(struct commit *commit)
-{
- struct commit_list **pp, *p;
-
- /* Examine existing parents while marking ones we have seen... */
- pp = &commit->parents;
- while ((p = *pp) != NULL) {
- struct commit *parent = p->item;
- if (parent->object.flags & TMP_MARK) {
- *pp = p->next;
- continue;
- }
- parent->object.flags |= TMP_MARK;
- pp = &p->next;
- }
- /* ... and clear the temporary mark */
- for (p = commit->parents; p; p = p->next)
- p->item->object.flags &= ~TMP_MARK;
-}
-
static int rewrite_parents(struct rev_info *revs, struct commit *commit)
{
struct commit_list **pp = &commit->parents;