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-rw-r--r--Documentation/git-rev-list.txt14
-rw-r--r--commit.c242
-rw-r--r--commit.h2
-rw-r--r--merge-base.c218
-rw-r--r--object.c9
-rw-r--r--object.h2
-rw-r--r--revision.c48
7 files changed, 312 insertions, 223 deletions
diff --git a/Documentation/git-rev-list.txt b/Documentation/git-rev-list.txt
index ad6d14c55..6c370e1be 100644
--- a/Documentation/git-rev-list.txt
+++ b/Documentation/git-rev-list.txt
@@ -15,6 +15,7 @@ SYNOPSIS
[ \--sparse ]
[ \--no-merges ]
[ \--remove-empty ]
+ [ \--not ]
[ \--all ]
[ \--topo-order ]
[ \--parents ]
@@ -37,6 +38,14 @@ not in 'baz'".
A special notation <commit1>..<commit2> can be used as a
short-hand for {caret}<commit1> <commit2>.
+Another special notation is <commit1>...<commit2> which is useful for
+merges. The resulting set of commits is the symmetric difference
+between the two operands. The following two commands are equivalent:
+
+------------
+$ git-rev-list A B --not $(git-merge-base --all A B)
+$ git-rev-list A...B
+------------
OPTIONS
-------
@@ -93,6 +102,11 @@ OPTIONS
--remove-empty::
Stop when a given path disappears from the tree.
+--not::
+ Reverses the meaning of the '{caret}' prefix (or lack
+ thereof) for all following revision specifiers, up to
+ the next `--not`.
+
--all::
Pretend as if all the refs in `$GIT_DIR/refs/` are
listed on the command line as <commit>.
diff --git a/commit.c b/commit.c
index e51ffa1c6..04390643e 100644
--- a/commit.c
+++ b/commit.c
@@ -846,3 +846,245 @@ void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
}
free(nodes);
}
+
+/* merge-rebase stuff */
+
+/* bits #0..7 in revision.h */
+#define PARENT1 (1u<< 8)
+#define PARENT2 (1u<< 9)
+#define STALE (1u<<10)
+
+static struct commit *interesting(struct commit_list *list)
+{
+ while (list) {
+ struct commit *commit = list->item;
+ list = list->next;
+ if (commit->object.flags & STALE)
+ continue;
+ return commit;
+ }
+ return NULL;
+}
+
+/*
+ * A pathological example of how this thing works.
+ *
+ * Suppose we had this commit graph, where chronologically
+ * the timestamp on the commit are A <= B <= C <= D <= E <= F
+ * and we are trying to figure out the merge base for E and F
+ * commits.
+ *
+ * F
+ * / \
+ * E A D
+ * \ / /
+ * B /
+ * \ /
+ * C
+ *
+ * First we push E and F to list to be processed. E gets bit 1
+ * and F gets bit 2. The list becomes:
+ *
+ * list=F(2) E(1), result=empty
+ *
+ * Then we pop F, the newest commit, from the list. Its flag is 2.
+ * We scan its parents, mark them reachable from the side that F is
+ * reachable from, and push them to the list:
+ *
+ * list=E(1) D(2) A(2), result=empty
+ *
+ * Next pop E and do the same.
+ *
+ * list=D(2) B(1) A(2), result=empty
+ *
+ * Next pop D and do the same.
+ *
+ * list=C(2) B(1) A(2), result=empty
+ *
+ * Next pop C and do the same.
+ *
+ * list=B(1) A(2), result=empty
+ *
+ * Now it is B's turn. We mark its parent, C, reachable from B's side,
+ * and push it to the list:
+ *
+ * list=C(3) A(2), result=empty
+ *
+ * Now pop C and notice it has flags==3. It is placed on the result list,
+ * and the list now contains:
+ *
+ * list=A(2), result=C(3)
+ *
+ * We pop A and do the same.
+ *
+ * list=B(3), result=C(3)
+ *
+ * Next, we pop B and something very interesting happens. It has flags==3
+ * so it is also placed on the result list, and its parents are marked
+ * stale, retroactively, and placed back on the list:
+ *
+ * list=C(7), result=C(7) B(3)
+ *
+ * Now, list does not have any interesting commit. So we find the newest
+ * commit from the result list that is not marked stale. Which is
+ * commit B.
+ *
+ *
+ * Another pathological example how this thing used to fail to mark an
+ * ancestor of a merge base as STALE before we introduced the
+ * postprocessing phase (mark_reachable_commits).
+ *
+ * 2
+ * H
+ * 1 / \
+ * G A \
+ * |\ / \
+ * | B \
+ * | \ \
+ * \ C F
+ * \ \ /
+ * \ D /
+ * \ | /
+ * \| /
+ * E
+ *
+ * list A B C D E F G H
+ * G1 H2 - - - - - - 1 2
+ * H2 E1 B1 - 1 - - 1 - 1 2
+ * F2 E1 B1 A2 2 1 - - 1 2 1 2
+ * E3 B1 A2 2 1 - - 3 2 1 2
+ * B1 A2 2 1 - - 3 2 1 2
+ * C1 A2 2 1 1 - 3 2 1 2
+ * D1 A2 2 1 1 1 3 2 1 2
+ * A2 2 1 1 1 3 2 1 2
+ * B3 2 3 1 1 3 2 1 2
+ * C7 2 3 7 1 3 2 1 2
+ *
+ * At this point, unfortunately, everybody in the list is
+ * stale, so we fail to complete the following two
+ * steps to fully marking stale commits.
+ *
+ * D7 2 3 7 7 3 2 1 2
+ * E7 2 3 7 7 7 2 1 2
+ *
+ * and we ended up showing E as an interesting merge base.
+ * The postprocessing phase re-injects C and continues traversal
+ * to contaminate D and E.
+ */
+
+static void mark_reachable_commits(struct commit_list *result,
+ struct commit_list *list)
+{
+ struct commit_list *tmp;
+
+ /*
+ * Postprocess to fully contaminate the well.
+ */
+ for (tmp = result; tmp; tmp = tmp->next) {
+ struct commit *c = tmp->item;
+ /* Reinject stale ones to list,
+ * so we can scan their parents.
+ */
+ if (c->object.flags & STALE)
+ commit_list_insert(c, &list);
+ }
+ while (list) {
+ struct commit *c = list->item;
+ struct commit_list *parents;
+
+ tmp = list;
+ list = list->next;
+ free(tmp);
+
+ /* Anything taken out of the list is stale, so
+ * mark all its parents stale. We do not
+ * parse new ones (we already parsed all the relevant
+ * ones).
+ */
+ parents = c->parents;
+ while (parents) {
+ struct commit *p = parents->item;
+ parents = parents->next;
+ if (!(p->object.flags & STALE)) {
+ p->object.flags |= STALE;
+ commit_list_insert(p, &list);
+ }
+ }
+ }
+}
+
+struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2,
+ int cleanup)
+{
+ struct commit_list *list = NULL;
+ struct commit_list *result = NULL;
+ struct commit_list *tmp = NULL;
+
+ if (rev1 == rev2)
+ return commit_list_insert(rev1, &result);
+
+ parse_commit(rev1);
+ parse_commit(rev2);
+
+ rev1->object.flags |= PARENT1;
+ rev2->object.flags |= PARENT2;
+ insert_by_date(rev1, &list);
+ insert_by_date(rev2, &list);
+
+ while (interesting(list)) {
+ struct commit *commit = list->item;
+ struct commit_list *parents;
+ int flags = commit->object.flags
+ & (PARENT1 | PARENT2 | STALE);
+
+ tmp = list;
+ list = list->next;
+ free(tmp);
+ if (flags == (PARENT1 | PARENT2)) {
+ insert_by_date(commit, &result);
+
+ /* Mark parents of a found merge stale */
+ flags |= STALE;
+ }
+ parents = commit->parents;
+ while (parents) {
+ struct commit *p = parents->item;
+ parents = parents->next;
+ if ((p->object.flags & flags) == flags)
+ continue;
+ parse_commit(p);
+ p->object.flags |= flags;
+ insert_by_date(p, &list);
+ }
+ }
+
+ if (!result)
+ goto finish;
+
+ if (result->next && list)
+ mark_reachable_commits(result, list);
+
+ /* cull duplicates */
+ for (tmp = result, list = NULL; tmp; ) {
+ struct commit *commit = tmp->item;
+ struct commit_list *next = tmp->next;
+ if (commit->object.flags & STALE) {
+ if (list != NULL)
+ list->next = next;
+ free(tmp);
+ } else {
+ if (list == NULL)
+ result = tmp;
+ list = tmp;
+ commit->object.flags |= STALE;
+ }
+
+ tmp = next;
+ }
+
+ finish:
+ if (cleanup)
+ clear_object_marks(PARENT1 | PARENT2 | STALE);
+
+ return result;
+}
diff --git a/commit.h b/commit.h
index 7c9ca3fbe..779ed82ed 100644
--- a/commit.h
+++ b/commit.h
@@ -105,4 +105,6 @@ struct commit_graft *read_graft_line(char *buf, int len);
int register_commit_graft(struct commit_graft *, int);
int read_graft_file(const char *graft_file);
+extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2, int cleanup);
+
#endif /* COMMIT_H */
diff --git a/merge-base.c b/merge-base.c
index 4856ca01c..59f723f40 100644
--- a/merge-base.c
+++ b/merge-base.c
@@ -2,232 +2,22 @@
#include "cache.h"
#include "commit.h"
-#define PARENT1 1
-#define PARENT2 2
-#define UNINTERESTING 4
-
-static struct commit *interesting(struct commit_list *list)
-{
- while (list) {
- struct commit *commit = list->item;
- list = list->next;
- if (commit->object.flags & UNINTERESTING)
- continue;
- return commit;
- }
- return NULL;
-}
-
-/*
- * A pathological example of how this thing works.
- *
- * Suppose we had this commit graph, where chronologically
- * the timestamp on the commit are A <= B <= C <= D <= E <= F
- * and we are trying to figure out the merge base for E and F
- * commits.
- *
- * F
- * / \
- * E A D
- * \ / /
- * B /
- * \ /
- * C
- *
- * First we push E and F to list to be processed. E gets bit 1
- * and F gets bit 2. The list becomes:
- *
- * list=F(2) E(1), result=empty
- *
- * Then we pop F, the newest commit, from the list. Its flag is 2.
- * We scan its parents, mark them reachable from the side that F is
- * reachable from, and push them to the list:
- *
- * list=E(1) D(2) A(2), result=empty
- *
- * Next pop E and do the same.
- *
- * list=D(2) B(1) A(2), result=empty
- *
- * Next pop D and do the same.
- *
- * list=C(2) B(1) A(2), result=empty
- *
- * Next pop C and do the same.
- *
- * list=B(1) A(2), result=empty
- *
- * Now it is B's turn. We mark its parent, C, reachable from B's side,
- * and push it to the list:
- *
- * list=C(3) A(2), result=empty
- *
- * Now pop C and notice it has flags==3. It is placed on the result list,
- * and the list now contains:
- *
- * list=A(2), result=C(3)
- *
- * We pop A and do the same.
- *
- * list=B(3), result=C(3)
- *
- * Next, we pop B and something very interesting happens. It has flags==3
- * so it is also placed on the result list, and its parents are marked
- * uninteresting, retroactively, and placed back on the list:
- *
- * list=C(7), result=C(7) B(3)
- *
- * Now, list does not have any interesting commit. So we find the newest
- * commit from the result list that is not marked uninteresting. Which is
- * commit B.
- *
- *
- * Another pathological example how this thing used to fail to mark an
- * ancestor of a merge base as UNINTERESTING before we introduced the
- * postprocessing phase (mark_reachable_commits).
- *
- * 2
- * H
- * 1 / \
- * G A \
- * |\ / \
- * | B \
- * | \ \
- * \ C F
- * \ \ /
- * \ D /
- * \ | /
- * \| /
- * E
- *
- * list A B C D E F G H
- * G1 H2 - - - - - - 1 2
- * H2 E1 B1 - 1 - - 1 - 1 2
- * F2 E1 B1 A2 2 1 - - 1 2 1 2
- * E3 B1 A2 2 1 - - 3 2 1 2
- * B1 A2 2 1 - - 3 2 1 2
- * C1 A2 2 1 1 - 3 2 1 2
- * D1 A2 2 1 1 1 3 2 1 2
- * A2 2 1 1 1 3 2 1 2
- * B3 2 3 1 1 3 2 1 2
- * C7 2 3 7 1 3 2 1 2
- *
- * At this point, unfortunately, everybody in the list is
- * uninteresting, so we fail to complete the following two
- * steps to fully marking uninteresting commits.
- *
- * D7 2 3 7 7 3 2 1 2
- * E7 2 3 7 7 7 2 1 2
- *
- * and we ended up showing E as an interesting merge base.
- * The postprocessing phase re-injects C and continues traversal
- * to contaminate D and E.
- */
-
static int show_all = 0;
-static void mark_reachable_commits(struct commit_list *result,
- struct commit_list *list)
-{
- struct commit_list *tmp;
-
- /*
- * Postprocess to fully contaminate the well.
- */
- for (tmp = result; tmp; tmp = tmp->next) {
- struct commit *c = tmp->item;
- /* Reinject uninteresting ones to list,
- * so we can scan their parents.
- */
- if (c->object.flags & UNINTERESTING)
- commit_list_insert(c, &list);
- }
- while (list) {
- struct commit *c = list->item;
- struct commit_list *parents;
-
- tmp = list;
- list = list->next;
- free(tmp);
-
- /* Anything taken out of the list is uninteresting, so
- * mark all its parents uninteresting. We do not
- * parse new ones (we already parsed all the relevant
- * ones).
- */
- parents = c->parents;
- while (parents) {
- struct commit *p = parents->item;
- parents = parents->next;
- if (!(p->object.flags & UNINTERESTING)) {
- p->object.flags |= UNINTERESTING;
- commit_list_insert(p, &list);
- }
- }
- }
-}
-
static int merge_base(struct commit *rev1, struct commit *rev2)
{
- struct commit_list *list = NULL;
- struct commit_list *result = NULL;
- struct commit_list *tmp = NULL;
-
- if (rev1 == rev2) {
- printf("%s\n", sha1_to_hex(rev1->object.sha1));
- return 0;
- }
-
- parse_commit(rev1);
- parse_commit(rev2);
-
- rev1->object.flags |= 1;
- rev2->object.flags |= 2;
- insert_by_date(rev1, &list);
- insert_by_date(rev2, &list);
-
- while (interesting(list)) {
- struct commit *commit = list->item;
- struct commit_list *parents;
- int flags = commit->object.flags & 7;
-
- tmp = list;
- list = list->next;
- free(tmp);
- if (flags == 3) {
- insert_by_date(commit, &result);
-
- /* Mark parents of a found merge uninteresting */
- flags |= UNINTERESTING;
- }
- parents = commit->parents;
- while (parents) {
- struct commit *p = parents->item;
- parents = parents->next;
- if ((p->object.flags & flags) == flags)
- continue;
- parse_commit(p);
- p->object.flags |= flags;
- insert_by_date(p, &list);
- }
- }
+ struct commit_list *result = get_merge_bases(rev1, rev2, 0);
if (!result)
return 1;
- if (result->next && list)
- mark_reachable_commits(result, list);
-
while (result) {
- struct commit *commit = result->item;
- result = result->next;
- if (commit->object.flags & UNINTERESTING)
- continue;
- printf("%s\n", sha1_to_hex(commit->object.sha1));
+ printf("%s\n", sha1_to_hex(result->item->object.sha1));
if (!show_all)
return 0;
- commit->object.flags |= UNINTERESTING;
+ result = result->next;
}
+
return 0;
}
diff --git a/object.c b/object.c
index 37277f943..1c3675971 100644
--- a/object.c
+++ b/object.c
@@ -235,3 +235,12 @@ void add_object_array(struct object *obj, const char *name, struct object_array
objects[nr].name = name;
array->nr = ++nr;
}
+
+void clear_object_marks(unsigned mark)
+{
+ int i;
+
+ for (i = 0; i < obj_hash_size; i++)
+ if (obj_hash[i])
+ obj_hash[i]->flags &= ~mark;
+}
diff --git a/object.h b/object.h
index e0125e154..d8a76ea93 100644
--- a/object.h
+++ b/object.h
@@ -84,4 +84,6 @@ int object_list_contains(struct object_list *list, struct object *obj);
/* Object array handling .. */
void add_object_array(struct object *obj, const char *name, struct object_array *array);
+void clear_object_marks(unsigned);
+
#endif /* OBJECT_H */
diff --git a/revision.c b/revision.c
index 880fb7bb3..56bc4ff0e 100644
--- a/revision.c
+++ b/revision.c
@@ -537,6 +537,18 @@ void init_revisions(struct rev_info *revs)
diff_setup(&revs->diffopt);
}
+static void add_pending_commit_list(struct rev_info *revs,
+ struct commit_list *commit_list,
+ unsigned int flags)
+{
+ while (commit_list) {
+ struct object *object = &commit_list->item->object;
+ object->flags |= flags;
+ add_pending_object(revs, object, sha1_to_hex(object->sha1));
+ commit_list = commit_list->next;
+ }
+}
+
/*
* Parse revision information, filling in the "rev_info" structure,
* and removing the used arguments from the argument list.
@@ -772,27 +784,45 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
unsigned char from_sha1[20];
const char *next = dotdot + 2;
const char *this = arg;
+ int symmetric = *next == '.';
+ unsigned int flags_exclude = flags ^ UNINTERESTING;
+
*dotdot = 0;
+ next += symmetric;
+
if (!*next)
next = "HEAD";
if (dotdot == arg)
this = "HEAD";
if (!get_sha1(this, from_sha1) &&
!get_sha1(next, sha1)) {
- struct object *exclude;
- struct object *include;
-
- exclude = get_reference(revs, this, from_sha1, flags ^ UNINTERESTING);
- include = get_reference(revs, next, sha1, flags);
- if (!exclude || !include)
- die("Invalid revision range %s..%s", arg, next);
+ struct commit *a, *b;
+ struct commit_list *exclude;
+
+ a = lookup_commit_reference(from_sha1);
+ b = lookup_commit_reference(sha1);
+ if (!a || !b) {
+ die(symmetric ?
+ "Invalid symmetric difference expression %s...%s" :
+ "Invalid revision range %s..%s",
+ arg, next);
+ }
if (!seen_dashdash) {
*dotdot = '.';
verify_non_filename(revs->prefix, arg);
}
- add_pending_object(revs, exclude, this);
- add_pending_object(revs, include, next);
+
+ if (symmetric) {
+ exclude = get_merge_bases(a, b, 1);
+ add_pending_commit_list(revs, exclude,
+ flags_exclude);
+ a->object.flags |= flags;
+ } else
+ a->object.flags |= flags_exclude;
+ b->object.flags |= flags;
+ add_pending_object(revs, &a->object, this);
+ add_pending_object(revs, &b->object, next);
continue;
}
*dotdot = '.';
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-15 05:58:58 +0000