If the commit-graph file becomes corrupt, we need a way to verify
that its contents match the object database. In the manner of
'git fsck' we will implement a 'git commit-graph verify' subcommand
to report all issues with the file.
Add the 'verify' subcommand to the 'commit-graph' builtin and its
documentation. The subcommand is currently a no-op except for
loading the commit-graph into memory, which may trigger run-time
errors that would be caught by normal use. Add a simple test that
ensures the command returns a zero error code.
If no commit-graph file exists, this is an acceptable state. Do
not report any errors.
During review, we noticed that a FREE_AND_NULL(graph_name) was
placed after a possible 'return', and this pattern was also in
graph_read(). Fix that case, too.
Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
Documentation/git-commit-graph.txt | 6 ++++++
builtin/commit-graph.c | 40 +++++++++++++++++++++++++++++++++++++-
commit-graph.c | 5 +++++
commit-graph.h | 2 ++
t/t5318-commit-graph.sh | 10 ++++++++++
5 files changed, 62 insertions(+), 1 deletion(-)
diff --git a/Documentation/git-commit-graph.txt
b/Documentation/git-commit-graph.txt
index 4c97b555cc..a222cfab08 100644
--- a/Documentation/git-commit-graph.txt
+++ b/Documentation/git-commit-graph.txt
@@ -10,6 +10,7 @@ SYNOPSIS
--------
[verse]
'git commit-graph read' [--object-dir <dir>]
+'git commit-graph verify' [--object-dir <dir>]
'git commit-graph write' <options> [--object-dir <dir>]
@@ -52,6 +53,11 @@ existing commit-graph file.
Read a graph file given by the commit-graph file and output basic
details about the graph file. Used for debugging purposes.
+'verify'::
+
+Read the commit-graph file and verify its contents against the object
+database. Used to check for corrupted data.
+
EXAMPLES
--------
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 37420ae0fd..af3101291f 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -8,10 +8,16 @@
static char const * const builtin_commit_graph_usage[] = {
N_("git commit-graph [--object-dir <objdir>]"),
N_("git commit-graph read [--object-dir <objdir>]"),
+ N_("git commit-graph verify [--object-dir <objdir>]"),
N_("git commit-graph write [--object-dir <objdir>] [--append]
[--stdin-packs|--stdin-commits]"),
NULL
};
+static const char * const builtin_commit_graph_verify_usage[] = {
+ N_("git commit-graph verify [--object-dir <objdir>]"),
+ NULL
+};
+
static const char * const builtin_commit_graph_read_usage[] = {
N_("git commit-graph read [--object-dir <objdir>]"),
NULL
@@ -29,6 +35,36 @@ static struct opts_commit_graph {
int append;
} opts;
+
+static int graph_verify(int argc, const char **argv)
+{
+ struct commit_graph *graph = 0;
+ char *graph_name;
+
+ static struct option builtin_commit_graph_verify_options[] = {
+ OPT_STRING(0, "object-dir", &opts.obj_dir,
+ N_("dir"),
+ N_("The object directory to store the graph")),
+ OPT_END(),
+ };
+
+ argc = parse_options(argc, argv, NULL,
+ builtin_commit_graph_verify_options,
+ builtin_commit_graph_verify_usage, 0);
+
+ if (!opts.obj_dir)
+ opts.obj_dir = get_object_directory();
+
+ graph_name = get_commit_graph_filename(opts.obj_dir);
+ graph = load_commit_graph_one(graph_name);
+ FREE_AND_NULL(graph_name);
+
+ if (!graph)
+ return 0;
+
+ return verify_commit_graph(graph);
+}
+
static int graph_read(int argc, const char **argv)
{
struct commit_graph *graph = NULL;
@@ -50,10 +86,10 @@ static int graph_read(int argc, const char **argv)
graph_name = get_commit_graph_filename(opts.obj_dir);
graph = load_commit_graph_one(graph_name);
+ FREE_AND_NULL(graph_name);
if (!graph)
die("graph file %s does not exist", graph_name);
- FREE_AND_NULL(graph_name);
printf("header: %08x %d %d %d %d\n",
ntohl(*(uint32_t*)graph->data),
@@ -160,6 +196,8 @@ int cmd_commit_graph(int argc, const char **argv, const
char *prefix)
PARSE_OPT_STOP_AT_NON_OPTION);
if (argc > 0) {
+ if (!strcmp(argv[0], "verify"))
+ return graph_verify(argc, argv);
if (!strcmp(argv[0], "read"))
return graph_read(argc, argv);
if (!strcmp(argv[0], "write"))
diff --git a/commit-graph.c b/commit-graph.c
index a8c337dd77..b25aaed128 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -817,3 +817,8 @@ void write_commit_graph(const char *obj_dir,
oids.alloc = 0;
oids.nr = 0;
}
+
+int verify_commit_graph(struct commit_graph *g)
+{
+ return !g;
+}
diff --git a/commit-graph.h b/commit-graph.h
index 96cccb10f3..71a39c5a57 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -53,4 +53,6 @@ void write_commit_graph(const char *obj_dir,
int nr_commits,
int append);
+int verify_commit_graph(struct commit_graph *g);
+
#endif
diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index 77d85aefe7..6ca451dfd2 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -11,6 +11,11 @@ test_expect_success 'setup full repo' '
objdir=".git/objects"
'
+test_expect_success 'verify graph with no graph file' '
+ cd "$TRASH_DIRECTORY/full" &&
+ git commit-graph verify
+'
+
test_expect_success 'write graph with no packs' '
cd "$TRASH_DIRECTORY/full" &&
git commit-graph write --object-dir . &&
@@ -230,4 +235,9 @@ test_expect_success 'perform fast-forward merge in full
repo' '
test_cmp expect output
'
+test_expect_success 'git commit-graph verify' '
+ cd "$TRASH_DIRECTORY/full" &&
+ git commit-graph verify >output
+'
+
test_done
--
2.16.2.329.gfb62395de6
