bundle: generate packfiles via the object database

git-bundle(1) spawns git-pack-objects(1) directly to generate the pack
data that gets appended to the bundle header. While bundles are not
part of the wire protocol, they are a transfer mechanism for packs all
the same, so convert them to use the pack generation interface of the
object database as well.

This makes the pack generator the single spawn point for all pack
streams that leave the repository, leaving only local maintenance tasks
like git-repack(1) with direct knowledge of git-pack-objects(1).

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: pks-t

builtin/bundle.c

@@ -68,8 +68,8 @@ static int parse_options_cmd_bundle(int argc,
 }
 
 static int cmd_bundle_create(int argc, const char **argv, const char *prefix,
-			     struct repository *repo UNUSED) {
-	struct strvec pack_opts = STRVEC_INIT;
+			     struct repository *repo UNUSED)
+{
 	int progress = isatty(STDERR_FILENO);
 	int version = -1;
 	struct option options[] = {
@@ -92,16 +92,9 @@ static int cmd_bundle_create(int argc, const char **argv, const char *prefix,
 			builtin_bundle_create_usage, options, &bundle_file);
 	/* bundle internals use argv[1] as further parameters */
 
-	if (progress)
-		strvec_push(&pack_opts, "--progress");
-	else
-		strvec_push(&pack_opts, "--quiet");
-	strvec_push(&pack_opts, "--all-progress-implied");
-
 	if (!startup_info->have_repository)
 		die(_("Need a repository to create a bundle."));
-	ret = !!create_bundle(the_repository, bundle_file, argc, argv, &pack_opts, version);
-	strvec_clear(&pack_opts);
+	ret = !!create_bundle(the_repository, bundle_file, argc, argv, version, progress);
 	free(bundle_file);
 	return ret;
 }

bundle.c

@@ -332,51 +332,52 @@ static int is_tag_in_date_range(struct repository *repo,
 
 
 /* Write the pack data to bundle_fd */
-static int write_pack_data(int bundle_fd, struct rev_info *revs, struct strvec *pack_options)
+static int write_pack_data(int bundle_fd, struct rev_info *revs, int progress)
 {
-	struct child_process pack_objects = CHILD_PROCESS_INIT;
+	struct odb_generate_pack_options opts = ODB_GENERATE_PACK_OPTIONS_INIT;
+	struct odb_pack_generator *generator;
+	int ret = 0;
 	int i;
 
-	strvec_pushl(&pack_objects.args,
-		     "pack-objects",
-		     "--stdout", "--thin", "--delta-base-offset",
-		     NULL);
-	strvec_pushv(&pack_objects.args, pack_options->v);
+	opts.thin = 1;
+	opts.ofs_delta = 1;
+	if (progress)
+		opts.progress = ODB_GENERATE_PACK_PROGRESS_VERBOSE;
 	if (revs->filter.choice)
-		strvec_pushf(&pack_objects.args, "--filter=%s",
-			     list_objects_filter_spec(&revs->filter));
-	pack_objects.in = -1;
-	pack_objects.out = bundle_fd;
-	pack_objects.git_cmd = 1;
+		opts.filter_spec = list_objects_filter_spec(&revs->filter);
 
 	/*
-	 * start_command() will close our descriptor if it's >1. Duplicate it
-	 * to avoid surprising the caller.
+	 * The pack generator will consume our descriptor if it's >1.
+	 * Duplicate it to avoid surprising the caller.
 	 */
-	if (pack_objects.out > 1) {
-		pack_objects.out = dup(pack_objects.out);
-		if (pack_objects.out < 0) {
-			error_errno(_("unable to dup bundle descriptor"));
-			child_process_clear(&pack_objects);
-			return -1;
-		}
+	opts.pack_fd = bundle_fd;
+	if (opts.pack_fd > 1) {
+		opts.pack_fd = dup(bundle_fd);
+		if (opts.pack_fd < 0)
+			return error_errno(_("unable to dup bundle descriptor"));
 	}
 
-	if (start_command(&pack_objects))
-		return error(_("Could not spawn pack-objects"));
-
 	for (i = 0; i < revs->pending.nr; i++) {
 		struct object *object = revs->pending.objects[i].item;
 		if (object->flags & UNINTERESTING)
-			write_or_die(pack_objects.in, "^", 1);
-		write_or_die(pack_objects.in, oid_to_hex(&object->oid),
-			     revs->repo->hash_algo->hexsz);
-		write_or_die(pack_objects.in, "\n", 1);
+			oid_array_append(&opts.haves, &object->oid);
+		else
+			oid_array_append(&opts.wants, &object->oid);
 	}
-	close(pack_objects.in);
-	if (finish_command(&pack_objects))
-		return error(_("pack-objects died"));
-	return 0;
+
+	if (odb_generate_pack(revs->repo->objects, &generator, &opts)) {
+		ret = error(_("Could not spawn pack-objects"));
+		goto out;
+	}
+
+	if (odb_pack_generator_finish(generator)) {
+		ret = error(_("pack-objects died"));
+		goto out;
+	}
+
+out:
+	odb_generate_pack_options_release(&opts);
+	return ret;
 }
 
 /*
@@ -485,7 +486,7 @@ static void write_bundle_prerequisites(struct commit *commit, void *data)
 }
 
 int create_bundle(struct repository *r, const char *path,
-		  int argc, const char **argv, struct strvec *pack_options, int version)
+		  int argc, const char **argv, int version, int progress)
 {
 	struct lock_file lock = LOCK_INIT;
 	int bundle_fd = -1;
@@ -594,7 +595,7 @@ int create_bundle(struct repository *r, const char *path,
 	}
 
 	/* write pack */
-	if (write_pack_data(bundle_fd, &revs_copy, pack_options)) {
+	if (write_pack_data(bundle_fd, &revs_copy, progress)) {
 		ret = -1;
 		goto out;
 	}

bundle.h

@@ -27,8 +27,7 @@ int read_bundle_header(const char *path, struct bundle_header *header);
 int read_bundle_header_fd(int fd, struct bundle_header *header,
 			  const char *report_path);
 int create_bundle(struct repository *r, const char *path,
-		  int argc, const char **argv, struct strvec *pack_options,
-		  int version);
+		  int argc, const char **argv, int version, int progress);
 
 enum verify_bundle_flags {
 	VERIFY_BUNDLE_VERBOSE = (1 << 0),