On 4/17/2018 1:00 PM, Derrick Stolee wrote:
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. This avoids duplicate work when we already
checked the graph in parse_commit_gently() or when simply checking the
buffer contents in check_commit().
Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
---
commit-graph.c | 51 ++++++++++++++++++++++++++++++++------------------
commit-graph.h | 8 ++++++++
commit.c | 7 +++++--
commit.h | 2 +-
object.c | 2 +-
sha1_file.c | 2 +-
6 files changed, 49 insertions(+), 23 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c
index 688d5b1801..21e853c21a 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -245,13 +245,19 @@ 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->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;
uint32_t *parent_data_ptr;
uint64_t date_low, date_high;
struct commit_list **pptr;
- const unsigned char *commit_data = g->chunk_commit_data + (g->hash_len + 16) * pos;
+ const unsigned char *commit_data = g->chunk_commit_data + GRAPH_DATA_WIDTH * pos;
item->object.parsed = 1;
item->graph_pos = pos;
@@ -292,31 +298,40 @@ 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(commit_graph, &(item->object.oid), pos);
The reference to 'commit_graph' in the above line should be 'g'. Sorry!
+ }
+}
+
int parse_commit_in_graph(struct commit *item)
{
+ uint32_t pos;
+
+ if (item->object.parsed)
+ return 0;
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 260a468e73..96cccb10f3 100644
--- 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 a70f120878..9ef6f699bd 100644
--- 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 64436ff44e..b5afde1ae9 100644
--- 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 e6ad3f61f0..efe4871325 100644
--- 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 1b94f39c4c..0fd4f0b8b6 100644
--- 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");
}
