[thirdparty/git.git] / clone-pack.c

#include "cache.h"
#include "refs.h"
#include "pkt-line.h"
#include <sys/wait.h>

static const char clone_pack_usage[] =
"git-clone-pack [--exec=<git-upload-pack>] [<host>:]<directory> [<heads>]*";
static const char *exec = "git-upload-pack";

static void clone_handshake(int fd[2], struct ref *ref)
{
	unsigned char sha1[20];

	while (ref) {
		packet_write(fd[1], "want %s\n", sha1_to_hex(ref->old_sha1));
		ref = ref->next;
	}
	packet_flush(fd[1]);

	/* We don't have nuttin' */
	packet_write(fd[1], "done\n");
	if (get_ack(fd[0], sha1))
		error("Huh! git-clone-pack got positive ack for %s", sha1_to_hex(sha1));
}

static int is_master(struct ref *ref)
{
	return !strcmp(ref->name, "refs/heads/master");
}

static void write_one_ref(struct ref *ref)
{
	char *path = git_path("%s", ref->name);
	int fd;
	char *hex;

	if (!strncmp(ref->name, "refs/", 5) &&
	    check_ref_format(ref->name + 5)) {
		error("refusing to create funny ref '%s' locally", ref->name);
		return;
	}

	if (safe_create_leading_directories(path))
		die("unable to create leading directory for %s", ref->name);
	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0666);
	if (fd < 0)
		die("unable to create ref %s", ref->name);
	hex = sha1_to_hex(ref->old_sha1);
	hex[40] = '\n';
	if (write(fd, hex, 41) != 41)
		die("unable to write ref %s", ref->name);
	close(fd);
}

static void write_refs(struct ref *ref)
{
	struct ref *head = NULL, *head_ptr, *master_ref;
	char *head_path;

	/* Upload-pack must report HEAD first */
	if (!strcmp(ref->name, "HEAD")) {
		head = ref;
		ref = ref->next;
	}
	head_ptr = NULL;
	master_ref = NULL;
	while (ref) {
		if (is_master(ref))
			master_ref = ref;
		if (head &&
		    !memcmp(ref->old_sha1, head->old_sha1, 20) &&
		    !strncmp(ref->name, "refs/heads/",11) &&
		    (!head_ptr || ref == master_ref))
			head_ptr = ref;

		write_one_ref(ref);
		ref = ref->next;
	}
	if (!head) {
		fprintf(stderr, "No HEAD in remote.\n");
		return;
	}

	head_path = strdup(git_path("HEAD"));
	if (!head_ptr) {
		/*
		 * If we had a master ref, and it wasn't HEAD, we need to undo the
		 * symlink, and write a standalone HEAD. Give a warning, because that's
		 * really really wrong.
		 */
		if (master_ref) {
			error("HEAD doesn't point to any refs! Making standalone HEAD");
			unlink(head_path);
		}
		write_one_ref(head);
		free(head_path);
		return;
	}

	/* We reset to the master branch if it's available */
	if (master_ref)
		return;

	fprintf(stderr, "Setting HEAD to %s\n", head_ptr->name);

	/*
	 * Uhhuh. Other end didn't have master. We start HEAD off with
	 * the first branch with the same value.
	 */
	if (create_symref(head_path, head_ptr->name) < 0)
		die("unable to link HEAD to %s", head_ptr->name);
	free(head_path);
}

static int finish_pack(const char *pack_tmp_name)
{
	int pipe_fd[2];
	pid_t pid;
	char idx[PATH_MAX];
	char final[PATH_MAX];
	char hash[41];
	unsigned char sha1[20];
	char *cp;
	int err = 0;

	if (pipe(pipe_fd) < 0)
		die("git-clone-pack: unable to set up pipe");

	strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
	cp = strrchr(idx, '/');
	memcpy(cp, "/pidx", 5);

	pid = fork();
	if (pid < 0)
		die("git-clone-pack: unable to fork off git-index-pack");
	if (!pid) {
		close(0);
		dup2(pipe_fd[1], 1);
		close(pipe_fd[0]);
		close(pipe_fd[1]);
		execlp("git-index-pack","git-index-pack",
		       "-o", idx, pack_tmp_name, NULL);
		error("cannot exec git-index-pack <%s> <%s>",
		      idx, pack_tmp_name);
		exit(1);
	}
	close(pipe_fd[1]);
	if (read(pipe_fd[0], hash, 40) != 40) {
		error("git-clone-pack: unable to read from git-index-pack");
		err = 1;
	}
	close(pipe_fd[0]);

	for (;;) {
		int status, code;
		int retval = waitpid(pid, &status, 0);

		if (retval < 0) {
			if (errno == EINTR)
				continue;
			error("waitpid failed (%s)", strerror(retval));
			goto error_die;
		}
		if (WIFSIGNALED(status)) {
			int sig = WTERMSIG(status);
			error("git-index-pack died of signal %d", sig);
			goto error_die;
		}
		if (!WIFEXITED(status)) {
			error("git-index-pack died of unnatural causes %d",
			      status);
			goto error_die;
		}
		code = WEXITSTATUS(status);
		if (code) {
			error("git-index-pack died with error code %d", code);
			goto error_die;
		}
		if (err)
			goto error_die;
		break;
	}
	hash[40] = 0;
	if (get_sha1_hex(hash, sha1)) {
		error("git-index-pack reported nonsense '%s'", hash);
		goto error_die;
	}
	/* Now we have pack in pack_tmp_name[], and
	 * idx in idx[]; rename them to their final names.
	 */
	snprintf(final, sizeof(final),
		 "%s/pack/pack-%s.pack", get_object_directory(), hash);
	move_temp_to_file(pack_tmp_name, final);
	chmod(final, 0444);
	snprintf(final, sizeof(final),
		 "%s/pack/pack-%s.idx", get_object_directory(), hash);
	move_temp_to_file(idx, final);
	chmod(final, 0444);
	return 0;

 error_die:
	unlink(idx);
	unlink(pack_tmp_name);
	exit(1);
}

static int clone_without_unpack(int fd[2])
{
	char tmpfile[PATH_MAX];
	int ofd, ifd;

	ifd = fd[0];
	snprintf(tmpfile, sizeof(tmpfile),
		 "%s/pack/tmp-XXXXXX", get_object_directory());
	ofd = mkstemp(tmpfile);
	if (ofd < 0)
		return error("unable to create temporary file %s", tmpfile);

	while (1) {
		char buf[8192];
		ssize_t sz, wsz, pos;
		sz = read(ifd, buf, sizeof(buf));
		if (sz == 0)
			break;
		if (sz < 0) {
			error("error reading pack (%s)", strerror(errno));
			close(ofd);
			unlink(tmpfile);
			return -1;
		}
		pos = 0;
		while (pos < sz) {
			wsz = write(ofd, buf + pos, sz - pos);
			if (wsz < 0) {
				error("error writing pack (%s)",
				      strerror(errno));
				close(ofd);
				unlink(tmpfile);
				return -1;
			}
			pos += wsz;
		}
	}
	close(ofd);
	return finish_pack(tmpfile);
}

static int clone_pack(int fd[2], int nr_match, char **match)
{
	struct ref *refs;
	int status;

	get_remote_heads(fd[0], &refs, nr_match, match, 1);
	if (!refs) {
		packet_flush(fd[1]);
		die("no matching remote head");
	}
	clone_handshake(fd, refs);

	status = clone_without_unpack(fd);

	if (!status)
		write_refs(refs);
	return status;
}

int main(int argc, char **argv)
{
	int i, ret, nr_heads;
	char *dest = NULL, **heads;
	int fd[2];
	pid_t pid;

	nr_heads = 0;
	heads = NULL;
	for (i = 1; i < argc; i++) {
		char *arg = argv[i];

		if (*arg == '-') {
			if (!strcmp("-q", arg))
				continue;
			if (!strncmp("--exec=", arg, 7)) {
				exec = arg + 7;
				continue;
			}
			if (!strcmp("--keep", arg))
				continue;
			usage(clone_pack_usage);
		}
		dest = arg;
		heads = argv + i + 1;
		nr_heads = argc - i - 1;
		break;
	}
	if (!dest)
		usage(clone_pack_usage);
	pid = git_connect(fd, dest, exec);
	if (pid < 0)
		return 1;
	ret = clone_pack(fd, nr_heads, heads);
	close(fd[0]);
	close(fd[1]);
	finish_connect(pid);
	return ret;
}
Commit	Line	Data
1fcc8ea5 LT	1	#include "cache.h"
	2	#include "refs.h"
	3	#include "pkt-line.h"
	4	#include <sys/wait.h>
	5
64c381bf	6	static const char clone_pack_usage[] =
e1c7ada6	7	"git-clone-pack [--exec=<git-upload-pack>] [<host>:]<directory> [<heads>]*";
1fcc8ea5 LT	8	static const char *exec = "git-upload-pack";
1fcc8ea5 LT	9
1fcc8ea5 LT	10	static void clone_handshake(int fd[2], struct ref *ref)
	11	{
	12	unsigned char sha1[20];
	13
	14	while (ref) {
d1c133f5	15	packet_write(fd[1], "want %s\n", sha1_to_hex(ref->old_sha1));
1fcc8ea5 LT	16	ref = ref->next;
	17	}
	18	packet_flush(fd[1]);
	19
	20	/* We don't have nuttin' */
	21	packet_write(fd[1], "done\n");
	22	if (get_ack(fd[0], sha1))
	23	error("Huh! git-clone-pack got positive ack for %s", sha1_to_hex(sha1));
	24	}
	25
	26	static int is_master(struct ref *ref)
	27	{
	28	return !strcmp(ref->name, "refs/heads/master");
	29	}
	30
	31	static void write_one_ref(struct ref *ref)
	32	{
4ec99bf0	33	char *path = git_path("%s", ref->name);
b2cb9425	34	int fd;
1fcc8ea5 LT	35	char *hex;
1fcc8ea5 LT	36
d8a1deec JH	37	if (!strncmp(ref->name, "refs/", 5) &&
	38	check_ref_format(ref->name + 5)) {
	39	error("refusing to create funny ref '%s' locally", ref->name);
	40	return;
	41	}
	42
b2cb9425 JH	43	if (safe_create_leading_directories(path))
	44	die("unable to create leading directory for %s", ref->name);
	45	fd = open(path, O_CREAT \| O_EXCL \| O_WRONLY, 0666);
1fcc8ea5 LT	46	if (fd < 0)
1fcc8ea5 LT	47	die("unable to create ref %s", ref->name);
d1c133f5	48	hex = sha1_to_hex(ref->old_sha1);
1fcc8ea5 LT	49	hex[40] = '\n';
	50	if (write(fd, hex, 41) != 41)
	51	die("unable to write ref %s", ref->name);
	52	close(fd);
	53	}
	54
	55	static void write_refs(struct ref *ref)
	56	{
	57	struct ref head = NULL, head_ptr, *master_ref;
	58	char *head_path;
	59
4cfc63db	60	/* Upload-pack must report HEAD first */
1fcc8ea5 LT	61	if (!strcmp(ref->name, "HEAD")) {
	62	head = ref;
	63	ref = ref->next;
	64	}
	65	head_ptr = NULL;
	66	master_ref = NULL;
	67	while (ref) {
	68	if (is_master(ref))
	69	master_ref = ref;
4cfc63db JH	70	if (head &&
	71	!memcmp(ref->old_sha1, head->old_sha1, 20) &&
	72	!strncmp(ref->name, "refs/heads/",11) &&
	73	(!head_ptr \|\| ref == master_ref))
	74	head_ptr = ref;
	75
1fcc8ea5 LT	76	write_one_ref(ref);
	77	ref = ref->next;
	78	}
4cfc63db JH	79	if (!head) {
4cfc63db JH	80	fprintf(stderr, "No HEAD in remote.\n");
1fcc8ea5	81	return;
4cfc63db	82	}
1fcc8ea5	83
4cfc63db	84	head_path = strdup(git_path("HEAD"));
1fcc8ea5 LT	85	if (!head_ptr) {
	86	/*
	87	* If we had a master ref, and it wasn't HEAD, we need to undo the
	88	* symlink, and write a standalone HEAD. Give a warning, because that's
	89	* really really wrong.
	90	*/
	91	if (master_ref) {
	92	error("HEAD doesn't point to any refs! Making standalone HEAD");
	93	unlink(head_path);
	94	}
	95	write_one_ref(head);
4cfc63db	96	free(head_path);
1fcc8ea5 LT	97	return;
	98	}
	99
	100	/* We reset to the master branch if it's available */
	101	if (master_ref)
	102	return;
	103
4cfc63db JH	104	fprintf(stderr, "Setting HEAD to %s\n", head_ptr->name);
4cfc63db JH	105
1fcc8ea5 LT	106	/*
	107	* Uhhuh. Other end didn't have master. We start HEAD off with
	108	* the first branch with the same value.
	109	*/
4cfc63db	110	if (create_symref(head_path, head_ptr->name) < 0)
1fcc8ea5	111	die("unable to link HEAD to %s", head_ptr->name);
4cfc63db	112	free(head_path);
1fcc8ea5 LT	113	}
1fcc8ea5 LT	114
11dcec07 JH	115	static int finish_pack(const char *pack_tmp_name)
	116	{
	117	int pipe_fd[2];
	118	pid_t pid;
	119	char idx[PATH_MAX];
	120	char final[PATH_MAX];
	121	char hash[41];
	122	unsigned char sha1[20];
	123	char *cp;
	124	int err = 0;
	125
	126	if (pipe(pipe_fd) < 0)
	127	die("git-clone-pack: unable to set up pipe");
	128
	129	strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
	130	cp = strrchr(idx, '/');
	131	memcpy(cp, "/pidx", 5);
	132
	133	pid = fork();
	134	if (pid < 0)
	135	die("git-clone-pack: unable to fork off git-index-pack");
	136	if (!pid) {
	137	close(0);
	138	dup2(pipe_fd[1], 1);
	139	close(pipe_fd[0]);
	140	close(pipe_fd[1]);
	141	execlp("git-index-pack","git-index-pack",
	142	"-o", idx, pack_tmp_name, NULL);
	143	error("cannot exec git-index-pack <%s> <%s>",
	144	idx, pack_tmp_name);
	145	exit(1);
	146	}
	147	close(pipe_fd[1]);
	148	if (read(pipe_fd[0], hash, 40) != 40) {
	149	error("git-clone-pack: unable to read from git-index-pack");
	150	err = 1;
	151	}
	152	close(pipe_fd[0]);
	153
	154	for (;;) {
	155	int status, code;
	156	int retval = waitpid(pid, &status, 0);
	157
	158	if (retval < 0) {
	159	if (errno == EINTR)
	160	continue;
	161	error("waitpid failed (%s)", strerror(retval));
	162	goto error_die;
	163	}
	164	if (WIFSIGNALED(status)) {
	165	int sig = WTERMSIG(status);
	166	error("git-index-pack died of signal %d", sig);
	167	goto error_die;
	168	}
	169	if (!WIFEXITED(status)) {
	170	error("git-index-pack died of unnatural causes %d",
	171	status);
	172	goto error_die;
	173	}
	174	code = WEXITSTATUS(status);
	175	if (code) {
	176	error("git-index-pack died with error code %d", code);
	177	goto error_die;
	178	}
179	if (err)
180	goto error_die;
181	break;
182	}
183	hash[40] = 0;
184	if (get_sha1_hex(hash, sha1)) {
185	error("git-index-pack reported nonsense '%s'", hash);
186	goto error_die;
187	}
188	/* Now we have pack in pack_tmp_name[], and
189	* idx in idx[]; rename them to their final names.
190	*/
191	snprintf(final, sizeof(final),
192	"%s/pack/pack-%s.pack", get_object_directory(), hash);
193	move_temp_to_file(pack_tmp_name, final);
64c381bf	194	chmod(final, 0444);
11dcec07 JH	195	snprintf(final, sizeof(final),
	196	"%s/pack/pack-%s.idx", get_object_directory(), hash);
	197	move_temp_to_file(idx, final);
64c381bf	198	chmod(final, 0444);
11dcec07 JH	199	return 0;
	200
	201	error_die:
	202	unlink(idx);
	203	unlink(pack_tmp_name);
	204	exit(1);
	205	}
	206
	207	static int clone_without_unpack(int fd[2])
	208	{
	209	char tmpfile[PATH_MAX];
	210	int ofd, ifd;
	211
	212	ifd = fd[0];
	213	snprintf(tmpfile, sizeof(tmpfile),
9e48b389	214	"%s/pack/tmp-XXXXXX", get_object_directory());
11dcec07 JH	215	ofd = mkstemp(tmpfile);
	216	if (ofd < 0)
	217	return error("unable to create temporary file %s", tmpfile);
	218
	219	while (1) {
	220	char buf[8192];
	221	ssize_t sz, wsz, pos;
	222	sz = read(ifd, buf, sizeof(buf));
	223	if (sz == 0)
	224	break;
	225	if (sz < 0) {
	226	error("error reading pack (%s)", strerror(errno));
	227	close(ofd);
	228	unlink(tmpfile);
	229	return -1;
	230	}
	231	pos = 0;
	232	while (pos < sz) {
	233	wsz = write(ofd, buf + pos, sz - pos);
	234	if (wsz < 0) {
	235	error("error writing pack (%s)",
	236	strerror(errno));
	237	close(ofd);
	238	unlink(tmpfile);
	239	return -1;
	240	}
	241	pos += wsz;
	242	}
	243	}
	244	close(ofd);
	245	return finish_pack(tmpfile);
	246	}
	247
	248	static int clone_pack(int fd[2], int nr_match, char **match)
	249	{
	250	struct ref *refs;
	251	int status;
	252
1a7141ff	253	get_remote_heads(fd[0], &refs, nr_match, match, 1);
11dcec07 JH	254	if (!refs) {
	255	packet_flush(fd[1]);
	256	die("no matching remote head");
	257	}
	258	clone_handshake(fd, refs);
	259
e1c7ada6	260	status = clone_without_unpack(fd);
11dcec07 JH	261
	262	if (!status)
	263	write_refs(refs);
	264	return status;
	265	}
	266
1fcc8ea5 LT	267	int main(int argc, char **argv)
	268	{
	269	int i, ret, nr_heads;
	270	char dest = NULL, *heads;
	271	int fd[2];
	272	pid_t pid;
	273
	274	nr_heads = 0;
	275	heads = NULL;
	276	for (i = 1; i < argc; i++) {
	277	char *arg = argv[i];
	278
	279	if (*arg == '-') {
e1c7ada6	280	if (!strcmp("-q", arg))
167a4a33	281	continue;
6ec311da JH	282	if (!strncmp("--exec=", arg, 7)) {
	283	exec = arg + 7;
	284	continue;
	285	}
e1c7ada6	286	if (!strcmp("--keep", arg))
11dcec07	287	continue;
1fcc8ea5 LT	288	usage(clone_pack_usage);
	289	}
	290	dest = arg;
	291	heads = argv + i + 1;
	292	nr_heads = argc - i - 1;
	293	break;
	294	}
	295	if (!dest)
	296	usage(clone_pack_usage);
	297	pid = git_connect(fd, dest, exec);
	298	if (pid < 0)
	299	return 1;
	300	ret = clone_pack(fd, nr_heads, heads);
	301	close(fd[0]);
	302	close(fd[1]);
	303	finish_connect(pid);
	304	return ret;
	305	}