[PATCH v2 1/8] fetch-pack: split up everything_local()

[Jonathan Tan]

The function everything_local(), despite its name, also (1) marks
commits as COMPLETE and COMMON_REF and (2) invokes filter_refs() as
important side effects. Extract (1) into its own function
(mark_complete_and_common_ref()) and remove
(2).

The restoring of save_commit_buffer, which was introduced in a1c6d7c1a7
("fetch-pack: restore save_commit_buffer after use", 2017-12-08), is a
concern of the parse_object() call in mark_complete_and_common_ref(), so
it has been moved from the end of everything_local() to the end of
mark_complete_and_common_ref().

Signed-off-by: Jonathan Tan <jonathanta...@google.com>
---
 fetch-pack.c | 39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

diff --git a/fetch-pack.c b/fetch-pack.c
index a320ce987..5c87bb8bb 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -734,12 +734,20 @@ static int add_loose_objects_to_set(const struct 
object_id *oid,
        return 0;
 }
 
-static int everything_local(struct fetch_pack_args *args,
-                           struct ref **refs,
-                           struct ref **sought, int nr_sought)
+/*
+ * Mark recent commits available locally and reachable from a local ref as
+ * COMPLETE. If args->no_dependents is false, also mark COMPLETE remote refs as
+ * COMMON_REF (otherwise, we are not planning to participate in negotiation, 
and
+ * thus do not need COMMON_REF marks).
+ *
+ * The cutoff time for recency is determined by this heuristic: it is the
+ * earliest commit time of the objects in refs that are commits and that we 
know
+ * the commit time of.
+ */
+static void mark_complete_and_common_ref(struct fetch_pack_args *args,
+                                        struct ref **refs)
 {
        struct ref *ref;
-       int retval;
        int old_save_commit_buffer = save_commit_buffer;
        timestamp_t cutoff = 0;
        struct oidset loose_oid_set = OIDSET_INIT;
@@ -812,7 +820,18 @@ static int everything_local(struct fetch_pack_args *args,
                }
        }
 
-       filter_refs(args, refs, sought, nr_sought);
+       save_commit_buffer = old_save_commit_buffer;
+}
+
+/*
+ * Returns 1 if every object pointed to by the given remote refs is available
+ * locally and reachable from a local ref, and 0 otherwise.
+ */
+static int everything_local(struct fetch_pack_args *args,
+                           struct ref **refs)
+{
+       struct ref *ref;
+       int retval;
 
        for (retval = 1, ref = *refs; ref ; ref = ref->next) {
                const struct object_id *remote = &ref->old_oid;
@@ -829,8 +848,6 @@ static int everything_local(struct fetch_pack_args *args,
                              ref->name);
        }
 
-       save_commit_buffer = old_save_commit_buffer;
-
        return retval;
 }
 
@@ -1053,7 +1070,9 @@ static struct ref *do_fetch_pack(struct fetch_pack_args 
*args,
        if (!server_supports("deepen-relative") && args->deepen_relative)
                die(_("Server does not support --deepen"));
 
-       if (everything_local(args, &ref, sought, nr_sought)) {
+       mark_complete_and_common_ref(args, &ref);
+       filter_refs(args, &ref, sought, nr_sought);
+       if (everything_local(args, &ref)) {
                packet_flush(fd[1]);
                goto all_done;
        }
@@ -1377,7 +1396,9 @@ static struct ref *do_fetch_pack_v2(struct 
fetch_pack_args *args,
                        for_each_cached_alternate(insert_one_alternate_object);
 
                        /* Filter 'ref' by 'sought' and those that aren't local 
*/
-                       if (everything_local(args, &ref, sought, nr_sought))
+                       mark_complete_and_common_ref(args, &ref);
+                       filter_refs(args, &ref, sought, nr_sought);
+                       if (everything_local(args, &ref))
                                state = FETCH_DONE;
                        else
                                state = FETCH_SEND_REQUEST;
-- 
2.17.0.768.g1526ddbba1.dirty