commit-graph: read only from specific pack-indexes

Teach git-commit-graph to inspect the objects only in a certain list
of pack-indexes within the given pack directory. This allows updating
the commit graph iteratively.

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

diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt
index 8aad8303f59caf20508d87bbd1a27fa05dbc16cc..8143cc3f078e46b0070c1212c1278b517db336e5 100644 (file)
--- a/Documentation/git-commit-graph.txt
+++ b/Documentation/git-commit-graph.txt
@@ -34,7 +34,9 @@ COMMANDS
 'write'::
 
 Write a commit graph file based on the commits found in packfiles.
-Includes all commits from the existing commit graph file.
++
+With the `--stdin-packs` option, generate the new commit graph by
+walking objects only in the specified pack-indexes.
 
 'read'::
 
@@ -51,6 +53,13 @@ EXAMPLES
 $ git commit-graph write
 ------------------------------------------------
 
+* Write a graph file, extending the current graph file using commits
+* in <pack-index>.
++
+------------------------------------------------
+$ echo <pack-index> | git commit-graph write --stdin-packs
+------------------------------------------------
+
 * Read basic information from the commit-graph file.
 +
 ------------------------------------------------

diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index efd39331d7c54b6039352719bc70c6dccc17aeda..5c7019900307f034d8c26b491fa416a7cfd35d8c 100644 (file)
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -8,7 +8,7 @@
 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 write [--object-dir <objdir>]"),
+       N_("git commit-graph write [--object-dir <objdir>] [--stdin-packs]"),
        NULL
 };
 
@@ -18,12 +18,13 @@ static const char * const builtin_commit_graph_read_usage[] = {
 };
 
 static const char * const builtin_commit_graph_write_usage[] = {
-       N_("git commit-graph write [--object-dir <objdir>]"),
+       N_("git commit-graph write [--object-dir <objdir>] [--stdin-packs]"),
        NULL
 };
 
 static struct opts_commit_graph {
        const char *obj_dir;
+       int stdin_packs;
 } opts;
 
 static int graph_read(int argc, const char **argv)
@@ -76,10 +77,18 @@ static int graph_read(int argc, const char **argv)
 
 static int graph_write(int argc, const char **argv)
 {
+       const char **pack_indexes = NULL;
+       int packs_nr = 0;
+       const char **lines = NULL;
+       int lines_nr = 0;
+       int lines_alloc = 0;
+
        static struct option builtin_commit_graph_write_options[] = {
                OPT_STRING(0, "object-dir", &opts.obj_dir,
                        N_("dir"),
                        N_("The object directory to store the graph")),
+               OPT_BOOL(0, "stdin-packs", &opts.stdin_packs,
+                       N_("scan pack-indexes listed by stdin for commits")),
                OPT_END(),
        };
 
@@ -90,7 +99,25 @@ static int graph_write(int argc, const char **argv)
        if (!opts.obj_dir)
                opts.obj_dir = get_object_directory();
 
-       write_commit_graph(opts.obj_dir);
+       if (opts.stdin_packs) {
+               struct strbuf buf = STRBUF_INIT;
+               lines_nr = 0;
+               lines_alloc = 128;
+               ALLOC_ARRAY(lines, lines_alloc);
+
+               while (strbuf_getline(&buf, stdin) != EOF) {
+                       ALLOC_GROW(lines, lines_nr + 1, lines_alloc);
+                       lines[lines_nr++] = strbuf_detach(&buf, NULL);
+               }
+
+               pack_indexes = lines;
+               packs_nr = lines_nr;
+       }
+
+       write_commit_graph(opts.obj_dir,
+                          pack_indexes,
+                          packs_nr);
+
        return 0;
 }
 

diff --git a/commit-graph.c b/commit-graph.c
index f745186e7f5ebaaea7852e7c6bfa3a275762c343..70472840a3bfb99fb0e1c63978f49d464df1fdb1 100644 (file)
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -549,7 +549,9 @@ static void close_reachable(struct packed_oid_list *oids)
        }
 }
 
-void write_commit_graph(const char *obj_dir)
+void write_commit_graph(const char *obj_dir,
+                       const char **pack_indexes,
+                       int nr_packs)
 {
        struct packed_oid_list oids;
        struct packed_commit_list commits;
@@ -571,7 +573,27 @@ void write_commit_graph(const char *obj_dir)
                oids.alloc = 1024;
        ALLOC_ARRAY(oids.list, oids.alloc);
 
-       for_each_packed_object(add_packed_commits, &oids, 0);
+       if (pack_indexes) {
+               struct strbuf packname = STRBUF_INIT;
+               int dirlen;
+               strbuf_addf(&packname, "%s/pack/", obj_dir);
+               dirlen = packname.len;
+               for (i = 0; i < nr_packs; i++) {
+                       struct packed_git *p;
+                       strbuf_setlen(&packname, dirlen);
+                       strbuf_addstr(&packname, pack_indexes[i]);
+                       p = add_packed_git(packname.buf, packname.len, 1);
+                       if (!p)
+                               die("error adding pack %s", packname.buf);
+                       if (open_pack_index(p))
+                               die("error opening index for %s", packname.buf);
+                       for_each_object_in_pack(p, add_packed_commits, &oids);
+                       close_pack(p);
+               }
+               strbuf_release(&packname);
+       } else
+               for_each_packed_object(add_packed_commits, &oids, 0);
+
        close_reachable(&oids);
 
        QSORT(oids.list, oids.nr, commit_compare);

diff --git a/commit-graph.h b/commit-graph.h
index 73b28beed15b952ced9ec1b0e978f507a552e823..f065f0866f83e274b0e9e8cdb10415b84d5d74f8 100644 (file)
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -36,6 +36,8 @@ struct commit_graph {
 
 struct commit_graph *load_commit_graph_one(const char *graph_file);
 
-void write_commit_graph(const char *obj_dir);
+void write_commit_graph(const char *obj_dir,
+                       const char **pack_indexes,
+                       int nr_packs);
 
 #endif

diff --git a/packfile.c b/packfile.c
index 5d07f330c8a4bf0a748e3fc87ed70f5affafd681..f14179f937e341b311fa8eb8d96106634c7a8977 100644 (file)
--- a/packfile.c
+++ b/packfile.c
@@ -304,7 +304,7 @@ void close_pack_index(struct packed_git *p)
        }
 }
 
-static void close_pack(struct packed_git *p)
+void close_pack(struct packed_git *p)
 {
        close_pack_windows(p);
        close_pack_fd(p);
@@ -1850,7 +1850,7 @@ int has_pack_index(const unsigned char *sha1)
        return 1;
 }
 
-static int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn cb, void *data)
+int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn cb, void *data)
 {
        uint32_t i;
        int r = 0;

diff --git a/packfile.h b/packfile.h
index a7fca598d672b73010a5fb99e4507da4634002ff..b341f2bf5ef68c0478d0d02cb208f999b175f699 100644 (file)
--- a/packfile.h
+++ b/packfile.h
@@ -63,6 +63,7 @@ extern void close_pack_index(struct packed_git *);
 
 extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
 extern void close_pack_windows(struct packed_git *);
+extern void close_pack(struct packed_git *);
 extern void close_all_packs(void);
 extern void unuse_pack(struct pack_window **);
 extern void clear_delta_base_cache(void);
@@ -140,6 +141,7 @@ typedef int each_packed_object_fn(const struct object_id *oid,
                                  struct packed_git *pack,
                                  uint32_t pos,
                                  void *data);
+extern int for_each_object_in_pack(struct packed_git *p, each_packed_object_fn, void *data);
 extern int for_each_packed_object(each_packed_object_fn, void *, unsigned flags);
 
 /*

diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index 51de9cc4552b088a22d1f38b5e79a2ac8d948b74..3bb44d0c09e15c771f68efa8fb2c24a86f340fa7 100755 (executable)
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -167,6 +167,16 @@ test_expect_success 'write graph with nothing new' '
 graph_git_behavior 'cleared graph, commit 8 vs merge 1' full commits/8 merge/1
 graph_git_behavior 'cleared graph, commit 8 vs merge 2' full commits/8 merge/2
 
+test_expect_success 'build graph from latest pack with closure' '
+       cd "$TRASH_DIRECTORY/full" &&
+       cat new-idx | git commit-graph write --stdin-packs &&
+       test_path_is_file $objdir/info/commit-graph &&
+       graph_read_expect "9" "large_edges"
+'
+
+graph_git_behavior 'graph from pack, commit 8 vs merge 1' full commits/8 merge/1
+graph_git_behavior 'graph from pack, commit 8 vs merge 2' full commits/8 merge/2
+
 test_expect_success 'setup bare repo' '
        cd "$TRASH_DIRECTORY" &&
        git clone --bare --no-local full bare &&