commit-graph: always load commit-graph information

Most code paths load commits using lookup_commit() and then
parse_commit(). In some cases, including some branch lookups, the commit
is parsed using parse_object_buffer() which side-steps parse_commit() in
favor of parse_commit_buffer().

With generation numbers in the commit-graph, we need to ensure that any
commit that exists in the commit-graph file has its generation number
loaded.

Create new load_commit_graph_info() method to fill in the information
for a commit that exists only in the commit-graph file. Call it from
parse_commit_buffer() after loading the other commit information from
the given buffer. Only fill this information when specified by the
'check_graph' parameter.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/commit-graph.c b/commit-graph.c
index 36d765e10a95708029ad7a003bf67cd0d9231838..a8c337dd7767a68c5720ae44a6da53e2137ace14 100644 (file)
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -245,6 +245,13 @@ static struct commit_list **insert_parent_or_die(struct commit_graph *g,
        return &commit_list_insert(c, pptr)->next;
 }
 
+static void fill_commit_graph_info(struct commit *item, struct commit_graph *g, uint32_t pos)
+{
+       const unsigned char *commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * pos;
+       item->graph_pos = pos;
+       item->generation = get_be32(commit_data + g->hash_len + 8) >> 2;
+}
+
 static int fill_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t pos)
 {
        uint32_t edge_value;
@@ -292,31 +299,40 @@ static int fill_commit_in_graph(struct commit *item, struct commit_graph *g, uin
        return 1;
 }
 
+static int find_commit_in_graph(struct commit *item, struct commit_graph *g, uint32_t *pos)
+{
+       if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
+               *pos = item->graph_pos;
+               return 1;
+       } else {
+               return bsearch_graph(g, &(item->object.oid), pos);
+       }
+}
+
 int parse_commit_in_graph(struct commit *item)
 {
+       uint32_t pos;
+
        if (!core_commit_graph)
                return 0;
        if (item->object.parsed)
                return 1;
-
        prepare_commit_graph();
-       if (commit_graph) {
-               uint32_t pos;
-               int found;
-               if (item->graph_pos != COMMIT_NOT_FROM_GRAPH) {
-                       pos = item->graph_pos;
-                       found = 1;
-               } else {
-                       found = bsearch_graph(commit_graph, &(item->object.oid), &pos);
-               }
-
-               if (found)
-                       return fill_commit_in_graph(item, commit_graph, pos);
-       }
-
+       if (commit_graph && find_commit_in_graph(item, commit_graph, &pos))
+               return fill_commit_in_graph(item, commit_graph, pos);
        return 0;
 }
 
+void load_commit_graph_info(struct commit *item)
+{
+       uint32_t pos;
+       if (!core_commit_graph)
+               return;
+       prepare_commit_graph();
+       if (commit_graph && find_commit_in_graph(item, commit_graph, &pos))
+               fill_commit_graph_info(item, commit_graph, pos);
+}
+
 static struct tree *load_tree_for_commit(struct commit_graph *g, struct commit *c)
 {
        struct object_id oid;

diff --git a/commit-graph.h b/commit-graph.h
index 260a468e73acd89b2a7706c859e8c25b264f3365..96cccb10f3d53a6da77f4ad06a971dbaa152f70c 100644 (file)
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -17,6 +17,14 @@ char *get_commit_graph_filename(const char *obj_dir);
  */
 int parse_commit_in_graph(struct commit *item);
 
+/*
+ * It is possible that we loaded commit contents from the commit buffer,
+ * but we also want to ensure the commit-graph content is correctly
+ * checked and filled. Fill the graph_pos and generation members of
+ * the given commit.
+ */
+void load_commit_graph_info(struct commit *item);
+
 struct tree *get_commit_tree_in_graph(const struct commit *c);
 
 struct commit_graph {

diff --git a/commit.c b/commit.c
index 4d00b0a1d6d7c9eb4c331a79c2172844aad854db..39a3749abd71536649e91dac2eacbfcb9f00eadd 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -331,7 +331,7 @@ const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
        return ret;
 }
 
-int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size)
+int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size, int check_graph)
 {
        const char *tail = buffer;
        const char *bufptr = buffer;
@@ -386,6 +386,9 @@ int parse_commit_buffer(struct commit *item, const void *buffer, unsigned long s
        }
        item->date = parse_commit_date(bufptr, tail);
 
+       if (check_graph)
+               load_commit_graph_info(item);
+
        return 0;
 }
 
@@ -412,7 +415,7 @@ int parse_commit_gently(struct commit *item, int quiet_on_missing)
                return error("Object %s not a commit",
                             oid_to_hex(&item->object.oid));
        }
-       ret = parse_commit_buffer(item, buffer, size);
+       ret = parse_commit_buffer(item, buffer, size, 0);
        if (save_commit_buffer && !ret) {
                set_commit_buffer(item, buffer, size);
                return 0;

diff --git a/commit.h b/commit.h
index 64436ff44e6b6e57074940d4c0c34af5c91da59f..b5afde1ae901d3b90643d8e84a3fbfe997f2ba65 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -72,7 +72,7 @@ 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 parse_commit_buffer(struct commit *item, const void *buffer, unsigned long size, int check_graph);
 int parse_commit_gently(struct commit *item, int quiet_on_missing);
 static inline int parse_commit(struct commit *item)
 {

diff --git a/object.c b/object.c
index e6ad3f61f03a98aa82dd901d96cbc230381c2e90..efe48713252a779c6e7425e8a40481d5881f7902 100644 (file)
--- a/object.c
+++ b/object.c
@@ -207,7 +207,7 @@ struct object *parse_object_buffer(const struct object_id *oid, enum object_type
        } else if (type == OBJ_COMMIT) {
                struct commit *commit = lookup_commit(oid);
                if (commit) {
-                       if (parse_commit_buffer(commit, buffer, size))
+                       if (parse_commit_buffer(commit, buffer, size, 1))
                                return NULL;
                        if (!get_cached_commit_buffer(commit, NULL)) {
                                set_commit_buffer(commit, buffer, size);

diff --git a/sha1_file.c b/sha1_file.c
index 1b94f39c4c5653b090d5dbecf0cf7a785b0556bb..0fd4f0b8b6d3205a9595ac697254e9c80257bffb 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1755,7 +1755,7 @@ static void check_commit(const void *buf, size_t size)
 {
        struct commit c;
        memset(&c, 0, sizeof(c));
-       if (parse_commit_buffer(&c, buf, size))
+       if (parse_commit_buffer(&c, buf, size, 0))
                die("corrupt commit");
 }