From: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
The can_all_from_reach_with_flag() algorithm was refactored in 4fbcca4e
"commit-reach: make can_all_from_reach... linear" but incorrectly
assumed that all objects provided were commits. During a fetch
negotiation, ok_to_give_up() in upload-pack.c may provide unpeeled tags
to the 'from' array. The current code creates a segfault.
Add a direct call to can_all_from_reach_with_flag() in 'test-tool reach'
and add a test in t6600-test-reach.sh that demonstrates this segfault.
Correct the issue by peeling tags when investigating the initial list
of objects in the 'from' array.
Signed-off-by: Jeff King <peff@xxxxxxxx>
Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
---
commit-reach.c | 33 ++++++++++++++++++++++++++-------
t/helper/test-reach.c | 22 +++++++++++++++++-----
t/t6600-test-reach.sh | 30 ++++++++++++++++++++++++++++--
3 files changed, 71 insertions(+), 14 deletions(-)
diff --git a/commit-reach.c b/commit-reach.c
index 86715c103c..4048a2132a 100644
--- a/commit-reach.c
+++ b/commit-reach.c
@@ -544,20 +544,39 @@ int can_all_from_reach_with_flag(struct object_array *from,
{
struct commit **list = NULL;
int i;
+ int nr_commits;
int result = 1;
ALLOC_ARRAY(list, from->nr);
+ nr_commits = 0;
for (i = 0; i < from->nr; i++) {
- list[i] = (struct commit *)from->objects[i].item;
+ struct object *from_one = from->objects[i].item;
- if (parse_commit(list[i]) ||
- list[i]->generation < min_generation)
- return 0;
+ if (!from_one || from_one->flags & assign_flag)
+ continue;
+
+ from_one = deref_tag(the_repository, from_one,
+ "a from object", 0);
+ if (!from_one || from_one->type != OBJ_COMMIT) {
+ /* no way to tell if this is reachable by
+ * looking at the ancestry chain alone, so
+ * leave a note to ourselves not to worry about
+ * this object anymore.
+ */
+ from->objects[i].item->flags |= assign_flag;
+ continue;
+ }
+
+ list[nr_commits] = (struct commit *)from_one;
+ if (parse_commit(list[nr_commits]) ||
+ list[nr_commits]->generation < min_generation)
+ return 0; /* is this a leak? */
+ nr_commits++;
}
- QSORT(list, from->nr, compare_commits_by_gen);
+ QSORT(list, nr_commits, compare_commits_by_gen);
- for (i = 0; i < from->nr; i++) {
+ for (i = 0; i < nr_commits; i++) {
/* DFS from list[i] */
struct commit_list *stack = NULL;
@@ -600,7 +619,7 @@ int can_all_from_reach_with_flag(struct object_array *from,
}
cleanup:
- for (i = 0; i < from->nr; i++) {
+ for (i = 0; i < nr_commits; i++) {
clear_commit_marks(list[i], RESULT);
clear_commit_marks(list[i], assign_flag);
}
diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c
index eb21103998..08d2ea68e8 100644
--- a/t/helper/test-reach.c
+++ b/t/helper/test-reach.c
@@ -31,6 +31,7 @@ int cmd__reach(int ac, const char **av)
struct object_id oid_A, oid_B;
struct commit *A, *B;
struct commit_list *X, *Y;
+ struct object_array X_obj = OBJECT_ARRAY_INIT;
struct commit **X_array;
int X_nr, X_alloc;
struct strbuf buf = STRBUF_INIT;
@@ -49,7 +50,8 @@ int cmd__reach(int ac, const char **av)
while (strbuf_getline(&buf, stdin) != EOF) {
struct object_id oid;
- struct object *o;
+ struct object *orig;
+ struct object *peeled;
struct commit *c;
if (buf.len < 3)
continue;
@@ -57,14 +59,14 @@ int cmd__reach(int ac, const char **av)
if (get_oid_committish(buf.buf + 2, &oid))
die("failed to resolve %s", buf.buf + 2);
- o = parse_object(r, &oid);
- o = deref_tag_noverify(o);
+ orig = parse_object(r, &oid);
+ peeled = deref_tag_noverify(orig);
- if (!o)
+ if (!peeled)
die("failed to load commit for input %s resulting in oid %s\n",
buf.buf, oid_to_hex(&oid));
- c = object_as_type(r, o, OBJ_COMMIT, 0);
+ c = object_as_type(r, peeled, OBJ_COMMIT, 0);
if (!c)
die("failed to load commit for input %s resulting in oid %s\n",
@@ -85,6 +87,7 @@ int cmd__reach(int ac, const char **av)
commit_list_insert(c, &X);
ALLOC_GROW(X_array, X_nr + 1, X_alloc);
X_array[X_nr++] = c;
+ add_object_array(orig, NULL, &X_obj);
break;
case 'Y':
@@ -113,6 +116,15 @@ int cmd__reach(int ac, const char **av)
print_sorted_commit_ids(list);
} else if (!strcmp(av[1], "can_all_from_reach")) {
printf("%s(X,Y):%d\n", av[1], can_all_from_reach(X, Y, 1));
+ } else if (!strcmp(av[1], "can_all_from_reach_with_flag")) {
+ struct commit_list *iter = Y;
+
+ while (iter) {
+ iter->item->object.flags |= 2;
+ iter = iter->next;
+ }
+
+ printf("%s(X,_,_,0,0):%d\n", av[1], can_all_from_reach_with_flag(&X_obj, 2, 4, 0, 0));
} else if (!strcmp(av[1], "commit_contains")) {
struct ref_filter filter;
struct contains_cache cache;
diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh
index d139a00d1d..ae94b27f70 100755
--- a/t/t6600-test-reach.sh
+++ b/t/t6600-test-reach.sh
@@ -31,7 +31,8 @@ test_expect_success 'setup' '
for i in $(test_seq 1 10)
do
test_commit "1-$i" &&
- git branch -f commit-1-$i
+ git branch -f commit-1-$i &&
+ git tag -a -m "1-$i" tag-1-$i commit-1-$i
done &&
for j in $(test_seq 1 9)
do
@@ -39,11 +40,13 @@ test_expect_success 'setup' '
x=$(($j + 1)) &&
test_commit "$x-1" &&
git branch -f commit-$x-1 &&
+ git tag -a -m "$x-1" tag-$x-1 commit-$x-1 &&
for i in $(test_seq 2 10)
do
git merge commit-$j-$i -m "$x-$i" &&
- git branch -f commit-$x-$i
+ git branch -f commit-$x-$i &&
+ git tag -a -m "$x-$i" tag-$x-$i commit-$x-$i
done
done &&
git commit-graph write --reachable &&
@@ -205,6 +208,29 @@ test_expect_success 'can_all_from_reach:miss' '
test_three_modes can_all_from_reach
'
+test_expect_success 'can_all_from_reach_with_flag: tags case' '
+ cat >input <<-\EOF &&
+ X:tag-2-10
+ X:tag-3-9
+ X:tag-4-8
+ X:commit-5-7
+ X:commit-6-6
+ X:commit-7-5
+ X:commit-8-4
+ X:commit-9-3
+ Y:tag-1-9
+ Y:tag-2-8
+ Y:tag-3-7
+ Y:commit-4-6
+ Y:commit-5-5
+ Y:commit-6-4
+ Y:commit-7-3
+ Y:commit-8-1
+ EOF
+ echo "can_all_from_reach_with_flag(X,_,_,0,0):1" >expect &&
+ test_three_modes can_all_from_reach_with_flag
+'
+
test_expect_success 'commit_contains:hit' '
cat >input <<-\EOF &&
A:commit-7-7
--
gitgitgadget
