[PATCH v2 06/12] commit: force commit to parse from object database

[Derrick Stolee]

In anticipation of verifying commit-graph file contents against the
object database, create parse_commit_internal() to allow side-stepping
the commit-graph file and parse directly from the object database.

Due to the use of generation numbers, this method should not be called
unless the intention is explicit in avoiding commits from the
commit-graph file.

Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
 commit.c | 13 +++++++++----
 commit.h |  1 +
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/commit.c b/commit.c
index 1d28677dfb..7c92350373 100644
--- a/commit.c
+++ b/commit.c
@@ -392,7 +392,7 @@ int parse_commit_buffer(struct commit *item, const void 
*buffer, unsigned long s
        return 0;
 }
 
-int parse_commit_gently(struct commit *item, int quiet_on_missing)
+int parse_commit_internal(struct commit *item, int quiet_on_missing, int 
use_commit_graph)
 {
        enum object_type type;
        void *buffer;
@@ -403,17 +403,17 @@ int parse_commit_gently(struct commit *item, int 
quiet_on_missing)
                return -1;
        if (item->object.parsed)
                return 0;
-       if (parse_commit_in_graph(item))
+       if (use_commit_graph && parse_commit_in_graph(item))
                return 0;
        buffer = read_sha1_file(item->object.oid.hash, &type, &size);
        if (!buffer)
                return quiet_on_missing ? -1 :
                        error("Could not read %s",
-                            oid_to_hex(&item->object.oid));
+                                       oid_to_hex(&item->object.oid));
        if (type != OBJ_COMMIT) {
                free(buffer);
                return error("Object %s not a commit",
-                            oid_to_hex(&item->object.oid));
+                               oid_to_hex(&item->object.oid));
        }
        ret = parse_commit_buffer(item, buffer, size, 0);
        if (save_commit_buffer && !ret) {
@@ -424,6 +424,11 @@ int parse_commit_gently(struct commit *item, int 
quiet_on_missing)
        return ret;
 }
 
+int parse_commit_gently(struct commit *item, int quiet_on_missing)
+{
+       return parse_commit_internal(item, quiet_on_missing, 1);
+}
+
 void parse_commit_or_die(struct commit *item)
 {
        if (parse_commit(item))
diff --git a/commit.h b/commit.h
index b5afde1ae9..5fde74fcd7 100644
--- a/commit.h
+++ b/commit.h
@@ -73,6 +73,7 @@ struct commit *lookup_commit_reference_by_name(const char 
*name);
 struct commit *lookup_commit_or_die(const struct object_id *oid, const char 
*ref_name);
 
 int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long 
size, int check_graph);
+int parse_commit_internal(struct commit *item, int quiet_on_missing, int 
use_commit_graph);
 int parse_commit_gently(struct commit *item, int quiet_on_missing);
 static inline int parse_commit(struct commit *item)
 {
-- 
2.16.2.329.gfb62395de6