It is possible to have multiple commit graph files in a pack directory,
but only one is important at a time. Use a 'graph_head' file to point
to the important file. Teach git-commit-graph to write 'graph_head' upon
writing a new commit graph file.
Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
Documentation/git-commit-graph.txt | 11 ++++++++++-
builtin/commit-graph.c | 27 +++++++++++++++++++++++++--
commit-graph.c | 8 ++++++++
commit-graph.h | 1 +
t/t5318-commit-graph.sh | 25 +++++++++++++++++++------
5 files changed, 63 insertions(+), 9 deletions(-)
diff --git a/Documentation/git-commit-graph.txt
b/Documentation/git-commit-graph.txt
index 67e107f06a..5e32c43b27 100644
--- a/Documentation/git-commit-graph.txt
+++ b/Documentation/git-commit-graph.txt
@@ -33,7 +33,9 @@ COMMANDS
Write a commit graph file based on the commits found in packfiles.
Includes all commits from the existing commit graph file. Outputs the
checksum hash of the written file.
-
++
+With `--update-head` option, update the graph-head file to point
+to the written graph file.
'read'::
@@ -53,6 +55,13 @@ EXAMPLES
$ git commit-graph write
------------------------------------------------
+* Write a graph file for the packed commits in your local .git folder
+* and update graph-head.
++
+------------------------------------------------
+$ git commit-graph write --update-head
+------------------------------------------------
+
* Read basic information from a graph file.
+
------------------------------------------------
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 3ffa7ec433..776ca087e8 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -1,12 +1,13 @@
#include "builtin.h"
#include "config.h"
+#include "lockfile.h"
#include "parse-options.h"
#include "commit-graph.h"
static char const * const builtin_commit_graph_usage[] = {
N_("git commit-graph [--pack-dir <packdir>]"),
N_("git commit-graph read [--graph-hash=<hash>]"),
- N_("git commit-graph write [--pack-dir <packdir>]"),
+ N_("git commit-graph write [--pack-dir <packdir>] [--update-head]"),
NULL
};
@@ -16,13 +17,14 @@ static const char * const builtin_commit_graph_read_usage[]
= {
};
static const char * const builtin_commit_graph_write_usage[] = {
- N_("git commit-graph write [--pack-dir <packdir>]"),
+ N_("git commit-graph write [--pack-dir <packdir>] [--update-head]"),
NULL
};
static struct opts_commit_graph {
const char *pack_dir;
const char *graph_hash;
+ int update_head;
} opts;
static int graph_read(int argc, const char **argv)
@@ -87,6 +89,22 @@ static int graph_read(int argc, const char **argv)
return 0;
}
+static void update_head_file(const char *pack_dir, const struct object_id
*graph_hash)
+{
+ int fd;
+ struct lock_file lk = LOCK_INIT;
+ char *head_fname = get_graph_head_filename(pack_dir);
+
+ fd = hold_lock_file_for_update(&lk, head_fname, LOCK_DIE_ON_ERROR);
+ FREE_AND_NULL(head_fname);
+
+ if (fd < 0)
+ die_errno("unable to open graph-head");
+
+ write_in_full(fd, oid_to_hex(graph_hash), GIT_MAX_HEXSZ);
+ commit_lock_file(&lk);
+}
+
static int graph_write(int argc, const char **argv)
{
struct object_id *graph_hash;
@@ -95,6 +113,8 @@ static int graph_write(int argc, const char **argv)
{ OPTION_STRING, 'p', "pack-dir", &opts.pack_dir,
N_("dir"),
N_("The pack directory to store the graph") },
+ OPT_BOOL('u', "update-head", &opts.update_head,
+ N_("update graph-head to written graph file")),
OPT_END(),
};
@@ -111,6 +131,9 @@ static int graph_write(int argc, const char **argv)
graph_hash = write_commit_graph(opts.pack_dir);
+ if (opts.update_head)
+ update_head_file(opts.pack_dir, graph_hash);
+
if (graph_hash) {
printf("%s\n", oid_to_hex(graph_hash));
FREE_AND_NULL(graph_hash);
diff --git a/commit-graph.c b/commit-graph.c
index 9a337cea4d..9789fe37f9 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -38,6 +38,14 @@
#define GRAPH_MIN_SIZE (GRAPH_CHUNKLOOKUP_SIZE + GRAPH_FANOUT_SIZE + \
GRAPH_OID_LEN + 8)
+char *get_graph_head_filename(const char *pack_dir)
+{
+ struct strbuf fname = STRBUF_INIT;
+ strbuf_addstr(&fname, pack_dir);
+ strbuf_addstr(&fname, "/graph-head");
+ return strbuf_detach(&fname, 0);
+}
+
char* get_commit_graph_filename_hash(const char *pack_dir,
struct object_id *hash)
{
diff --git a/commit-graph.h b/commit-graph.h
index c1608976b3..726b8aa0f4 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -4,6 +4,7 @@
#include "git-compat-util.h"
#include "commit.h"
+extern char *get_graph_head_filename(const char *pack_dir);
extern char* get_commit_graph_filename_hash(const char *pack_dir,
struct object_id *hash);
diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index ad1d0e621d..21352d5a3c 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -11,7 +11,8 @@ test_expect_success 'setup full repo' '
packdir=".git/objects/pack"'
test_expect_success 'write graph with no packs' '
- git commit-graph write --pack-dir .'
+ git commit-graph write --pack-dir . &&
+ test_path_is_missing graph-head'
test_expect_success 'create commits and repack' '
for i in $(test_seq 3)
@@ -32,6 +33,7 @@ graph_read_expect() {
test_expect_success 'write graph' '
graph1=$(git commit-graph write) &&
+ test_path_is_missing graph-head &&
test_path_is_file $packdir/graph-$graph1.graph &&
git commit-graph read --graph-hash=$graph1 >output &&
graph_read_expect "3" "$packdir" &&
@@ -73,8 +75,11 @@ test_expect_success 'Add more commits' '
test_expect_success 'write graph with merges' '
- graph2=$(git commit-graph write)&&
+ graph2=$(git commit-graph write --update-head)&&
test_path_is_file $packdir/graph-$graph2.graph &&
+ test_path_is_file $packdir/graph-head &&
+ printf $graph2 >expect &&
+ test_cmp expect $packdir/graph-head &&
git commit-graph read --graph-hash=$graph2 >output &&
graph_read_expect "10" "$packdir" &&
test_cmp expect output'
@@ -99,19 +104,24 @@ test_expect_success 'Add one more commit' '
# 1
test_expect_success 'write graph with new commit' '
- graph3=$(git commit-graph write) &&
- test_path_is_file $packdir/graph-$graph3.graph &&
+ graph3=$(git commit-graph write --update-head) &&
test_path_is_file $packdir/graph-$graph3.graph &&
+ test_path_is_file $packdir/graph-head &&
+ printf $graph3 >expect &&
+ test_cmp expect $packdir/graph-head &&
git commit-graph read --graph-hash=$graph3 >output &&
graph_read_expect "11" "$packdir" &&
test_cmp expect output'
test_expect_success 'write graph with nothing new' '
- graph4=$(git commit-graph write) &&
+ graph4=$(git commit-graph write --update-head) &&
test_path_is_file $packdir/graph-$graph4.graph &&
printf $graph3 >expect &&
printf $graph4 >output &&
test_cmp expect output &&
+ test_path_is_file $packdir/graph-head &&
+ printf $graph4 >expect &&
+ test_cmp expect $packdir/graph-head &&
git commit-graph read --graph-hash=$graph4 >output &&
graph_read_expect "11" "$packdir" &&
test_cmp expect output'
@@ -123,8 +133,11 @@ test_expect_success 'setup bare repo' '
baredir="./objects/pack"'
test_expect_success 'write graph in bare repo' '
- graphbare=$(git commit-graph write) &&
+ graphbare=$(git commit-graph write --update-head) &&
test_path_is_file $baredir/graph-$graphbare.graph &&
+ test_path_is_file $baredir/graph-head &&
+ printf $graphbare >expect &&
+ test_cmp expect $baredir/graph-head &&
git commit-graph read --graph-hash=$graphbare >output &&
graph_read_expect "11" "$baredir" &&
test_cmp expect output'
--
2.15.1.45.g9b7079f
