[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 old_sha1[20];
	unsigned char new_sha1[20];
	char ref_name[0];
};

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 void 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))
		die("unpack should have generated %s, but I can't find it!", new_hex);

	newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
	if (newfd < 0)
		die("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);
		die("unable to write %s", lock_name);
	}
	if (verify_old_ref(name, old_hex) < 0) {
		unlink(lock_name);
		die("%s changed during push", name);
	}
	if (run_update_hook(name, old_hex, new_hex)) {
		unlink(lock_name);
		fprintf(stderr, "hook declined to update %s\n", name);
	}
	else if (rename(lock_name, name) < 0) {
		unlink(lock_name);
		die("unable to replace %s", name);
	}
	else
		fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
}


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

	while (cmd) {
		update(cmd->ref_name, cmd->old_sha1, cmd->new_sha1);
		cmd = cmd->next;
	}
	run_update_hook("", NULL, NULL);
}

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 0;
	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");
	setenv("GIT_DIR", ".", 1);

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