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

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

static const char receive_pack_usage[] = "git-receive-pack <git-dir>";

static const char unpacker[] = "git-unpack-objects";

static int show_ref(const char *path, const unsigned char *sha1)
{
	packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
	return 0;
}

static void write_head_info(void)
{
	for_each_ref(show_ref);
}

struct command {
	struct command *next;
	unsigned char updated;
	unsigned char old_sha1[20];
	unsigned char new_sha1[20];
	char ref_name[];
};

static struct command *commands = NULL;

static int is_all_zeroes(const char *hex)
{
	int i;
	for (i = 0; i < 40; i++)
		if (*hex++ != '0')
			return 0;
	return 1;
}

static int verify_old_ref(const char *name, char *hex_contents)
{
	int fd, ret;
	char buffer[60];

	if (is_all_zeroes(hex_contents))
		return 0;
	fd = open(name, O_RDONLY);
	if (fd < 0)
		return -1;
	ret = read(fd, buffer, 40);
	close(fd);
	if (ret != 40)
		return -1;
	if (memcmp(buffer, hex_contents, 40))
		return -1;
	return 0;
}

static char update_hook[] = "hooks/update";

static int run_update_hook(const char *refname,
			   char *old_hex, char *new_hex)
{
	int code;

	if (access(update_hook, X_OK) < 0)
		return 0;
	code = run_command(update_hook, refname, old_hex, new_hex, NULL);
	switch (code) {
	case 0:
		return 0;
	case -ERR_RUN_COMMAND_FORK:
		die("hook fork failed");
	case -ERR_RUN_COMMAND_EXEC:
		die("hook execute failed");
	case -ERR_RUN_COMMAND_WAITPID:
		die("waitpid failed");
	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
		die("waitpid is confused");
	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
		fprintf(stderr, "%s died of signal", update_hook);
		return -1;
	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
		die("%s died strangely", update_hook);
	default:
		error("%s exited with error code %d", update_hook, -code);
		return -code;
	}
}

static int update(const char *name,
		  unsigned char *old_sha1, unsigned char *new_sha1)
{
	char new_hex[60], *old_hex, *lock_name;
	int newfd, namelen, written;

	namelen = strlen(name);
	lock_name = xmalloc(namelen + 10);
	memcpy(lock_name, name, namelen);
	memcpy(lock_name + namelen, ".lock", 6);

	strcpy(new_hex, sha1_to_hex(new_sha1));
	old_hex = sha1_to_hex(old_sha1);
	if (!has_sha1_file(new_sha1))
		return error("unpack should have generated %s, "
			     "but I can't find it!", new_hex);

	safe_create_leading_directories(lock_name);

	newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
	if (newfd < 0)
		return error("unable to create %s (%s)",
			     lock_name, strerror(errno));

	/* Write the ref with an ending '\n' */
	new_hex[40] = '\n';
	new_hex[41] = 0;
	written = write(newfd, new_hex, 41);
	/* Remove the '\n' again */
	new_hex[40] = 0;

	close(newfd);
	if (written != 41) {
		unlink(lock_name);
		return error("unable to write %s", lock_name);
	}
	if (verify_old_ref(name, old_hex) < 0) {
		unlink(lock_name);
		return error("%s changed during push", name);
	}
	if (run_update_hook(name, old_hex, new_hex)) {
		unlink(lock_name);
		return error("hook declined to update %s\n", name);
	}
	else if (rename(lock_name, name) < 0) {
		unlink(lock_name);
		return error("unable to replace %s", name);
	}
	else {
		fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
		return 0;
	}
}

static char update_post_hook[] = "hooks/post-update";

static void run_update_post_hook(struct command *cmd)
{
	struct command *cmd_p;
	int argc;
	char **argv;

	if (access(update_post_hook, X_OK) < 0)
		return;
	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
		if (!cmd_p->updated)
			continue;
		argc++;
	}
	argv = xmalloc(sizeof(*argv) * (1 + argc));
	argv[0] = update_post_hook;

	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
		if (!cmd_p->updated)
			continue;
		argv[argc] = xmalloc(strlen(cmd_p->ref_name) + 1);
		strcpy(argv[argc], cmd_p->ref_name);
		argc++;
	}
	argv[argc] = NULL;
	run_command_v(argc, argv);
}

/*
 * This gets called after(if) we've successfully
 * unpacked the data payload.
 */
static void execute_commands(void)
{
	struct command *cmd = commands;

	while (cmd) {
		cmd->updated = !update(cmd->ref_name,
				       cmd->old_sha1, cmd->new_sha1);
		cmd = cmd->next;
	}
	run_update_post_hook(commands);
}

static void read_head_info(void)
{
	struct command **p = &commands;
	for (;;) {
		static char line[1000];
		unsigned char old_sha1[20], new_sha1[20];
		struct command *cmd;
		int len;

		len = packet_read_line(0, line, sizeof(line));
		if (!len)
			break;
		if (line[len-1] == '\n')
			line[--len] = 0;
		if (len < 83 ||
		    line[40] != ' ' ||
		    line[81] != ' ' ||
		    get_sha1_hex(line, old_sha1) ||
		    get_sha1_hex(line + 41, new_sha1))
			die("protocol error: expected old/new/ref, got '%s'", line);
		cmd = xmalloc(sizeof(struct command) + len - 80);
		memcpy(cmd->old_sha1, old_sha1, 20);
		memcpy(cmd->new_sha1, new_sha1, 20);
		memcpy(cmd->ref_name, line + 82, len - 81);
		cmd->next = NULL;
		*p = cmd;
		p = &cmd->next;
	}
}

static void unpack(void)
{
	int code = run_command(unpacker, NULL);
	switch (code) {
	case 0:
		return;
	case -ERR_RUN_COMMAND_FORK:
		die("unpack fork failed");
	case -ERR_RUN_COMMAND_EXEC:
		die("unpack execute failed");
	case -ERR_RUN_COMMAND_WAITPID:
		die("waitpid failed");
	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
		die("waitpid is confused");
	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
		die("%s died of signal", unpacker);
	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
		die("%s died strangely", unpacker);
	default:
		die("%s exited with error code %d", unpacker, -code);
	}
}

int main(int argc, char **argv)
{
	int i;
	const char *dir = NULL;

	argv++;
	for (i = 1; i < argc; i++) {
		const char *arg = *argv++;

		if (*arg == '-') {
			/* Do flag handling here */
			usage(receive_pack_usage);
		}
		if (dir)
			usage(receive_pack_usage);
		dir = arg;
	}
	if (!dir)
		usage(receive_pack_usage);

	/* chdir to the directory. If that fails, try appending ".git" */
	if (chdir(dir) < 0) {
		if (chdir(mkpath("%s.git", dir)) < 0)
			die("unable to cd to %s", dir);
	}

	/* If we have a ".git" directory, chdir to it */
	chdir(".git");
	putenv("GIT_DIR=.");

	if (access("objects", X_OK) < 0 || access("refs/heads", X_OK) < 0)
		die("%s doesn't appear to be a git directory", dir);
	write_head_info();

	/* EOF */
	packet_flush(1);

	read_head_info();
	if (commands) {
		unpack();
		execute_commands();
	}
	return 0;
}
Commit	Line	Data
575f4974	1	#include "cache.h"
8a65ff76	2	#include "refs.h"
f3a3214e	3	#include "pkt-line.h"
b1bf95bb	4	#include "run-command.h"
575f4974 LT	5	#include <sys/wait.h>
575f4974 LT	6
d0efc8a7	7	static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
575f4974	8
b1bf95bb	9	static const char unpacker[] = "git-unpack-objects";
575f4974	10
944d8589	11	static int show_ref(const char path, const unsigned char sha1)
575f4974	12	{
f3a3214e	13	packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
8a65ff76	14	return 0;
575f4974 LT	15	}
575f4974 LT	16
8a65ff76	17	static void write_head_info(void)
575f4974	18	{
8a65ff76	19	for_each_ref(show_ref);
575f4974 LT	20	}
575f4974 LT	21
eb1af2df LT	22	struct command {
eb1af2df LT	23	struct command *next;
19614330	24	unsigned char updated;
eb1af2df LT	25	unsigned char old_sha1[20];
eb1af2df LT	26	unsigned char new_sha1[20];
6c5f9baa	27	char ref_name[];
575f4974 LT	28	};
575f4974 LT	29
6da4016a	30	static struct command *commands = NULL;
575f4974	31
f65fdf04 LT	32	static int is_all_zeroes(const char *hex)
	33	{
	34	int i;
	35	for (i = 0; i < 40; i++)
	36	if (*hex++ != '0')
	37	return 0;
	38	return 1;
	39	}
	40
2eca23da LT	41	static int verify_old_ref(const char name, char hex_contents)
	42	{
	43	int fd, ret;
	44	char buffer[60];
	45
f65fdf04 LT	46	if (is_all_zeroes(hex_contents))
f65fdf04 LT	47	return 0;
2eca23da LT	48	fd = open(name, O_RDONLY);
	49	if (fd < 0)
	50	return -1;
	51	ret = read(fd, buffer, 40);
	52	close(fd);
	53	if (ret != 40)
	54	return -1;
	55	if (memcmp(buffer, hex_contents, 40))
	56	return -1;
	57	return 0;
	58	}
	59
b1bf95bb JW	60	static char update_hook[] = "hooks/update";
	61
	62	static int run_update_hook(const char *refname,
	63	char old_hex, char new_hex)
	64	{
	65	int code;
	66
	67	if (access(update_hook, X_OK) < 0)
	68	return 0;
	69	code = run_command(update_hook, refname, old_hex, new_hex, NULL);
	70	switch (code) {
	71	case 0:
	72	return 0;
	73	case -ERR_RUN_COMMAND_FORK:
	74	die("hook fork failed");
	75	case -ERR_RUN_COMMAND_EXEC:
	76	die("hook execute failed");
	77	case -ERR_RUN_COMMAND_WAITPID:
	78	die("waitpid failed");
	79	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
	80	die("waitpid is confused");
	81	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
	82	fprintf(stderr, "%s died of signal", update_hook);
	83	return -1;
	84	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
	85	die("%s died strangely", update_hook);
	86	default:
	87	error("%s exited with error code %d", update_hook, -code);
	88	return -code;
	89	}
	90	}
	91
19614330 JH	92	static int update(const char *name,
19614330 JH	93	unsigned char old_sha1, unsigned char new_sha1)
2eca23da LT	94	{
	95	char new_hex[60], old_hex, lock_name;
	96	int newfd, namelen, written;
	97
	98	namelen = strlen(name);
	99	lock_name = xmalloc(namelen + 10);
	100	memcpy(lock_name, name, namelen);
	101	memcpy(lock_name + namelen, ".lock", 6);
	102
	103	strcpy(new_hex, sha1_to_hex(new_sha1));
2eca23da LT	104	old_hex = sha1_to_hex(old_sha1);
2eca23da LT	105	if (!has_sha1_file(new_sha1))
19614330 JH	106	return error("unpack should have generated %s, "
19614330 JH	107	"but I can't find it!", new_hex);
2eca23da	108
29f3b3de JH	109	safe_create_leading_directories(lock_name);
29f3b3de JH	110
f312de01	111	newfd = open(lock_name, O_CREAT \| O_EXCL \| O_WRONLY, 0666);
2eca23da	112	if (newfd < 0)
19614330 JH	113	return error("unable to create %s (%s)",
19614330 JH	114	lock_name, strerror(errno));
f65fdf04 LT	115
	116	/* Write the ref with an ending '\n' */
	117	new_hex[40] = '\n';
	118	new_hex[41] = 0;
2eca23da	119	written = write(newfd, new_hex, 41);
f65fdf04 LT	120	/* Remove the '\n' again */
	121	new_hex[40] = 0;
	122
2eca23da LT	123	close(newfd);
	124	if (written != 41) {
	125	unlink(lock_name);
19614330	126	return error("unable to write %s", lock_name);
2eca23da LT	127	}
	128	if (verify_old_ref(name, old_hex) < 0) {
	129	unlink(lock_name);
19614330	130	return error("%s changed during push", name);
2eca23da	131	}
b1bf95bb JW	132	if (run_update_hook(name, old_hex, new_hex)) {
b1bf95bb JW	133	unlink(lock_name);
19614330	134	return error("hook declined to update %s\n", name);
b1bf95bb JW	135	}
b1bf95bb JW	136	else if (rename(lock_name, name) < 0) {
2eca23da	137	unlink(lock_name);
19614330	138	return error("unable to replace %s", name);
2eca23da	139	}
19614330	140	else {
b1bf95bb	141	fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
19614330 JH	142	return 0;
19614330 JH	143	}
2eca23da LT	144	}
2eca23da LT	145
19614330 JH	146	static char update_post_hook[] = "hooks/post-update";
	147
	148	static void run_update_post_hook(struct command *cmd)
	149	{
	150	struct command *cmd_p;
	151	int argc;
	152	char **argv;
	153
	154	if (access(update_post_hook, X_OK) < 0)
	155	return;
	156	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
	157	if (!cmd_p->updated)
	158	continue;
	159	argc++;
	160	}
	161	argv = xmalloc(sizeof(argv) (1 + argc));
	162	argv[0] = update_post_hook;
	163
	164	for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
	165	if (!cmd_p->updated)
	166	continue;
	167	argv[argc] = xmalloc(strlen(cmd_p->ref_name) + 1);
	168	strcpy(argv[argc], cmd_p->ref_name);
	169	argc++;
	170	}
	171	argv[argc] = NULL;
	172	run_command_v(argc, argv);
	173	}
2eca23da	174
575f4974 LT	175	/*
	176	* This gets called after(if) we've successfully
	177	* unpacked the data payload.
	178	*/
	179	static void execute_commands(void)
	180	{
eb1af2df LT	181	struct command *cmd = commands;
	182
	183	while (cmd) {
19614330 JH	184	cmd->updated = !update(cmd->ref_name,
19614330 JH	185	cmd->old_sha1, cmd->new_sha1);
eb1af2df	186	cmd = cmd->next;
575f4974	187	}
19614330	188	run_update_post_hook(commands);
575f4974 LT	189	}
	190
	191	static void read_head_info(void)
	192	{
eb1af2df	193	struct command **p = &commands;
575f4974 LT	194	for (;;) {
575f4974 LT	195	static char line[1000];
eb1af2df LT	196	unsigned char old_sha1[20], new_sha1[20];
	197	struct command *cmd;
	198	int len;
	199
	200	len = packet_read_line(0, line, sizeof(line));
575f4974 LT	201	if (!len)
575f4974 LT	202	break;
eb1af2df LT	203	if (line[len-1] == '\n')
	204	line[--len] = 0;
	205	if (len < 83 \|\|
	206	line[40] != ' ' \|\|
	207	line[81] != ' ' \|\|
	208	get_sha1_hex(line, old_sha1) \|\|
	209	get_sha1_hex(line + 41, new_sha1))
	210	die("protocol error: expected old/new/ref, got '%s'", line);
	211	cmd = xmalloc(sizeof(struct command) + len - 80);
	212	memcpy(cmd->old_sha1, old_sha1, 20);
	213	memcpy(cmd->new_sha1, new_sha1, 20);
	214	memcpy(cmd->ref_name, line + 82, len - 81);
	215	cmd->next = NULL;
	216	*p = cmd;
	217	p = &cmd->next;
575f4974 LT	218	}
	219	}
	220
	221	static void unpack(void)
	222	{
b1bf95bb JW	223	int code = run_command(unpacker, NULL);
	224	switch (code) {
	225	case 0:
c742b813	226	return;
b1bf95bb	227	case -ERR_RUN_COMMAND_FORK:
575f4974	228	die("unpack fork failed");
b1bf95bb	229	case -ERR_RUN_COMMAND_EXEC:
575f4974	230	die("unpack execute failed");
b1bf95bb JW	231	case -ERR_RUN_COMMAND_WAITPID:
	232	die("waitpid failed");
	233	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
	234	die("waitpid is confused");
	235	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
	236	die("%s died of signal", unpacker);
	237	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
	238	die("%s died strangely", unpacker);
	239	default:
	240	die("%s exited with error code %d", unpacker, -code);
575f4974 LT	241	}
	242	}
	243
	244	int main(int argc, char **argv)
	245	{
d0efc8a7	246	int i;
575f4974	247	const char *dir = NULL;
575f4974 LT	248
	249	argv++;
	250	for (i = 1; i < argc; i++) {
	251	const char arg = argv++;
	252
	253	if (*arg == '-') {
575f4974 LT	254	/* Do flag handling here */
	255	usage(receive_pack_usage);
	256	}
d0efc8a7 LT	257	if (dir)
d0efc8a7 LT	258	usage(receive_pack_usage);
575f4974	259	dir = arg;
575f4974 LT	260	}
	261	if (!dir)
	262	usage(receive_pack_usage);
	263
	264	/* chdir to the directory. If that fails, try appending ".git" */
	265	if (chdir(dir) < 0) {
113b9475	266	if (chdir(mkpath("%s.git", dir)) < 0)
575f4974 LT	267	die("unable to cd to %s", dir);
	268	}
	269
	270	/* If we have a ".git" directory, chdir to it */
	271	chdir(".git");
e72a7d45	272	putenv("GIT_DIR=.");
575f4974 LT	273
	274	if (access("objects", X_OK) < 0 \|\| access("refs/heads", X_OK) < 0)
	275	die("%s doesn't appear to be a git directory", dir);
8a65ff76	276	write_head_info();
575f4974 LT	277
575f4974 LT	278	/* EOF */
f3a3214e	279	packet_flush(1);
575f4974 LT	280
575f4974 LT	281	read_head_info();
7f8e9828 LT	282	if (commands) {
	283	unpack();
	284	execute_commands();
	285	}
575f4974 LT	286	return 0;
575f4974 LT	287	}