* with the remote-tracking branch to find the value
* to expect, but we did not have such a tracking
* branch.
+ *
+ * If the tip of the remote-tracking ref is unreachable
+ * from any reflog entry of its local ref indicating a
+ * possible update since checkout; reject the push.
*/
if (ref->expect_old_sha1) {
if (!oideq(&ref->old_oid, &ref->old_oid_expect))
reject_reason = REF_STATUS_REJECT_STALE;
+ else if (ref->check_reachable && ref->unreachable)
+ reject_reason =
+ REF_STATUS_REJECT_REMOTE_UPDATED;
else
- /* If the ref isn't stale then force the update. */
+ /*
+ * If the ref isn't stale, and is reachable
+ * from from one of the reflog entries of
+ * the local branch, force the update.
+ */
force_ref_update = 1;
}
/*
* Look at remote.fetch refspec and see if we have a remote
- * tracking branch for the refname there. Fill its current
- * value in sha1[].
+ * tracking branch for the refname there. Fill the name of
+ * the remote-tracking branch in *dst_refname, and the name
+ * of the commit object at its tip in oid[].
* If we cannot do so, return negative to signal an error.
*/
static int remote_tracking(struct remote *remote, const char *refname,
- struct object_id *oid)
+ struct object_id *oid, char **dst_refname)
{
char *dst;
return -1; /* no tracking ref for refname at remote */
if (read_ref(dst, oid))
return -1; /* we know what the tracking ref is but we cannot read it */
+
+ *dst_refname = dst;
return 0;
}
+/*
+ * The struct "reflog_commit_array" and related helper functions
+ * are used for collecting commits into an array during reflog
+ * traversals in "check_and_collect_until()".
+ */
+struct reflog_commit_array {
+ struct commit **item;
+ size_t nr, alloc;
+};
+
+#define REFLOG_COMMIT_ARRAY_INIT { NULL, 0, 0 }
+
+/* Append a commit to the array. */
+static void append_commit(struct reflog_commit_array *arr,
+ struct commit *commit)
+{
+ ALLOC_GROW(arr->item, arr->nr + 1, arr->alloc);
+ arr->item[arr->nr++] = commit;
+}
+
+/* Free and reset the array. */
+static void free_commit_array(struct reflog_commit_array *arr)
+{
+ FREE_AND_NULL(arr->item);
+ arr->nr = arr->alloc = 0;
+}
+
+struct check_and_collect_until_cb_data {
+ struct commit *remote_commit;
+ struct reflog_commit_array *local_commits;
+ timestamp_t remote_reflog_timestamp;
+};
+
+/* Get the timestamp of the latest entry. */
+static int peek_reflog(struct object_id *o_oid, struct object_id *n_oid,
+ const char *ident, timestamp_t timestamp,
+ int tz, const char *message, void *cb_data)
+{
+ timestamp_t *ts = cb_data;
+ *ts = timestamp;
+ return 1;
+}
+
+static int check_and_collect_until(struct object_id *o_oid,
+ struct object_id *n_oid,
+ const char *ident, timestamp_t timestamp,
+ int tz, const char *message, void *cb_data)
+{
+ struct commit *commit;
+ struct check_and_collect_until_cb_data *cb = cb_data;
+
+ /* An entry was found. */
+ if (oideq(n_oid, &cb->remote_commit->object.oid))
+ return 1;
+
+ if ((commit = lookup_commit_reference(the_repository, n_oid)))
+ append_commit(cb->local_commits, commit);
+
+ /*
+ * If the reflog entry timestamp is older than the remote ref's
+ * latest reflog entry, there is no need to check or collect
+ * entries older than this one.
+ */
+ if (timestamp < cb->remote_reflog_timestamp)
+ return -1;
+
+ return 0;
+}
+
+#define MERGE_BASES_BATCH_SIZE 8
+
+/*
+ * Iterate through the reflog of the local ref to check if there is an entry
+ * for the given remote-tracking ref; runs until the timestamp of an entry is
+ * older than latest timestamp of remote-tracking ref's reflog. Any commits
+ * are that seen along the way are collected into an array to check if the
+ * remote-tracking ref is reachable from any of them.
+ */
+static int is_reachable_in_reflog(const char *local, const struct ref *remote)
+{
+ timestamp_t date;
+ struct commit *commit;
+ struct commit **chunk;
+ struct check_and_collect_until_cb_data cb;
+ struct reflog_commit_array arr = REFLOG_COMMIT_ARRAY_INIT;
+ size_t size = 0;
+ int ret = 0;
+
+ commit = lookup_commit_reference(the_repository, &remote->old_oid);
+ if (!commit)
+ goto cleanup_return;
+
+ /*
+ * Get the timestamp from the latest entry
+ * of the remote-tracking ref's reflog.
+ */
+ for_each_reflog_ent_reverse(remote->tracking_ref, peek_reflog, &date);
+
+ cb.remote_commit = commit;
+ cb.local_commits = &arr;
+ cb.remote_reflog_timestamp = date;
+ ret = for_each_reflog_ent_reverse(local, check_and_collect_until, &cb);
+
+ /* We found an entry in the reflog. */
+ if (ret > 0)
+ goto cleanup_return;
+
+ /*
+ * Check if the remote commit is reachable from any
+ * of the commits in the collected array, in batches.
+ */
+ for (chunk = arr.item; chunk < arr.item + arr.nr; chunk += size) {
+ size = arr.item + arr.nr - chunk;
+ if (MERGE_BASES_BATCH_SIZE < size)
+ size = MERGE_BASES_BATCH_SIZE;
+
+ if ((ret = in_merge_bases_many(commit, size, chunk)))
+ break;
+ }
+
+cleanup_return:
+ free_commit_array(&arr);
+ return ret;
+}
+
+/*
+ * Check for reachability of a remote-tracking
+ * ref in the reflog entries of its local ref.
+ */
+static void check_if_includes_upstream(struct ref *remote)
+{
+ struct ref *local = get_local_ref(remote->name);
+ if (!local)
+ return;
+
+ if (is_reachable_in_reflog(local->name, remote) <= 0)
+ remote->unreachable = 1;
+}
+
static void apply_cas(struct push_cas_option *cas,
struct remote *remote,
struct ref *ref)
ref->expect_old_sha1 = 1;
if (!entry->use_tracking)
oidcpy(&ref->old_oid_expect, &entry->expect);
- else if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
+ else if (remote_tracking(remote, ref->name,
+ &ref->old_oid_expect,
+ &ref->tracking_ref))
oidclr(&ref->old_oid_expect);
+ else
+ ref->check_reachable = cas->use_force_if_includes;
return;
}
return;
ref->expect_old_sha1 = 1;
- if (remote_tracking(remote, ref->name, &ref->old_oid_expect))
+ if (remote_tracking(remote, ref->name,
+ &ref->old_oid_expect,
+ &ref->tracking_ref))
oidclr(&ref->old_oid_expect);
+ else
+ ref->check_reachable = cas->use_force_if_includes;
}
void apply_push_cas(struct push_cas_option *cas,
struct ref *remote_refs)
{
struct ref *ref;
- for (ref = remote_refs; ref; ref = ref->next)
+ for (ref = remote_refs; ref; ref = ref->next) {
apply_cas(cas, remote, ref);
+
+ /*
+ * If "compare-and-swap" is in "use_tracking[_for_rest]"
+ * mode, and if "--force-if-includes" was specified, run
+ * the check.
+ */
+ if (ref->check_reachable)
+ check_if_includes_upstream(ref);
+ }
}
projects / thirdparty / git.git / blobdiff