send-pack.c - jrn/git - Git at Google

 #include "cache.h"
 #include "commit.h"
 #include "tag.h"
 #include "refs.h"
 #include "pkt-line.h"

 static const char send_pack_usage[] =
 "git-send-pack [--all] [--exec=git-receive-pack] <remote> [<head>...]\n"
 "  --all and explicit <head> specification are mutually exclusive.";
 static const char *exec = "git-receive-pack";
 static int verbose = 0;
 static int send_all = 0;
 static int force_update = 0;

 static int is_zero_sha1(const unsigned char *sha1)
 {
 	int i;

 	for (i = 0; i < 20; i++) {
 		if (*sha1++)
 			return 0;
 	}
 	return 1;
 }

 static void exec_pack_objects(void)
 {
 	static char *args[] = {
 		"git-pack-objects",
 		"--stdout",
 		NULL
 	};
 	execvp("git-pack-objects", args);
 	die("git-pack-objects exec failed (%s)", strerror(errno));
 }

 static void exec_rev_list(struct ref *refs)
 {
 	static char *args[1000];
 	int i = 0;

 	args[i++] = "git-rev-list";	/* 0 */
 	args[i++] = "--objects";	/* 1 */
 	while (refs) {
 		char *buf = malloc(100);
 		if (i > 900)
 			die("git-rev-list environment overflow");
 		if (!is_zero_sha1(refs->old_sha1) &&
 		    has_sha1_file(refs->old_sha1)) {
 			args[i++] = buf;
 			snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
 			buf += 50;
 		}
 		if (!is_zero_sha1(refs->new_sha1)) {
 			args[i++] = buf;
 			snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
 		}
 		refs = refs->next;
 	}
 	args[i] = NULL;
 	execvp("git-rev-list", args);
 	die("git-rev-list exec failed (%s)", strerror(errno));
 }

 static void rev_list(int fd, struct ref *refs)
 {
 	int pipe_fd[2];
 	pid_t pack_objects_pid;

 	if (pipe(pipe_fd) < 0)
 		die("rev-list setup: pipe failed");
 	pack_objects_pid = fork();
 	if (!pack_objects_pid) {
 		dup2(pipe_fd[0], 0);
 		dup2(fd, 1);
 		close(pipe_fd[0]);
 		close(pipe_fd[1]);
 		close(fd);
 		exec_pack_objects();
 		die("pack-objects setup failed");
 	}
 	if (pack_objects_pid < 0)
 		die("pack-objects fork failed");
 	dup2(pipe_fd[1], 1);
 	close(pipe_fd[0]);
 	close(pipe_fd[1]);
 	close(fd);
 	exec_rev_list(refs);
 }

 static int pack_objects(int fd, struct ref *refs)
 {
 	pid_t rev_list_pid;

 	rev_list_pid = fork();
 	if (!rev_list_pid) {
 		rev_list(fd, refs);
 		die("rev-list setup failed");
 	}
 	if (rev_list_pid < 0)
 		die("rev-list fork failed");
 	/*
 	 * We don't wait for the rev-list pipeline in the parent:
 	 * we end up waiting for the other end instead
 	 */
 	return 0;
 }

 static void unmark_and_free(struct commit_list *list, unsigned int mark)
 {
 	while (list) {
 		struct commit_list *temp = list;
 		temp->item->object.flags &= ~mark;
 		list = temp->next;
 		free(temp);
 	}
 }

 static int ref_newer(const unsigned char *new_sha1,
 		     const unsigned char *old_sha1)
 {
 	struct object *o;
 	struct commit *old, *new;
 	struct commit_list *list, *used;
 	int found = 0;

 	/* Both new and old must be commit-ish and new is descendant of
 	 * old.  Otherwise we require --force.
 	 */
 	o = deref_tag(parse_object(old_sha1), NULL, 0);
 	if (!o || o->type != commit_type)
 		return 0;
 	old = (struct commit *) o;

 	o = deref_tag(parse_object(new_sha1), NULL, 0);
 	if (!o || o->type != commit_type)
 		return 0;
 	new = (struct commit *) o;

 	if (parse_commit(new) < 0)
 		return 0;

 	used = list = NULL;
 	commit_list_insert(new, &list);
 	while (list) {
 		new = pop_most_recent_commit(&list, 1);
 		commit_list_insert(new, &used);
 		if (new == old) {
 			found = 1;
 			break;
 		}
 	}
 	unmark_and_free(list, 1);
 	unmark_and_free(used, 1);
 	return found;
 }

 static struct ref *local_refs, **local_tail;
 static struct ref *remote_refs, **remote_tail;

 static int one_local_ref(const char *refname, const unsigned char *sha1)
 {
 	struct ref *ref;
 	int len = strlen(refname) + 1;
 	ref = xcalloc(1, sizeof(*ref) + len);
 	memcpy(ref->new_sha1, sha1, 20);
 	memcpy(ref->name, refname, len);
 	*local_tail = ref;
 	local_tail = &ref->next;
 	return 0;
 }

 static void get_local_heads(void)
 {
 	local_tail = &local_refs;
 	for_each_ref(one_local_ref);
 }

 static int send_pack(int in, int out, int nr_refspec, char **refspec)
 {
 	struct ref *ref;
 	int new_refs;
 	int ret = 0;

 	/* No funny business with the matcher */
 	remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, 1);
 	get_local_heads();

 	/* match them up */
 	if (!remote_tail)
 		remote_tail = &remote_refs;
 	if (match_refs(local_refs, remote_refs, &remote_tail,
 		       nr_refspec, refspec, send_all))
 		return -1;

 	if (!remote_refs) {
 		fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 		return 0;
 	}

 	/*
 	 * Finally, tell the other end!
 	 */
 	new_refs = 0;
 	for (ref = remote_refs; ref; ref = ref->next) {
 		char old_hex[60], *new_hex;
 		if (!ref->peer_ref)
 			continue;
 		if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
 			if (verbose)
 				fprintf(stderr, "'%s': up-to-date\n", ref->name);
 			continue;
 		}

 		/* This part determines what can overwrite what.
 		 * The rules are:
 		 *
 		 * (0) you can always use --force or +A:B notation to
 		 *     selectively force individual ref pairs.
 		 *
 		 * (1) if the old thing does not exist, it is OK.
 		 *
 		 * (2) if you do not have the old thing, you are not allowed
 		 *     to overwrite it; you would not know what you are losing
 		 *     otherwise.
 		 *
 		 * (3) if both new and old are commit-ish, and new is a
 		 *     descendant of old, it is OK.
 		 */

 		if (!force_update &&
 		    !is_zero_sha1(ref->old_sha1) &&
 		    !ref->force) {
 			if (!has_sha1_file(ref->old_sha1)) {
 				error("remote '%s' object %s does not "
 				      "exist on local",
 				      ref->name, sha1_to_hex(ref->old_sha1));
 				ret = -2;
 				continue;
 			}

 			/* We assume that local is fsck-clean.  Otherwise
 			 * you _could_ have an old tag which points at
 			 * something you do not have, which may or may not
 			 * be a commit.
 			 */
 			if (!ref_newer(ref->peer_ref->new_sha1,
 				       ref->old_sha1)) {
 				error("remote ref '%s' is not a strict "
 				      "subset of local ref '%s'.", ref->name,
 				      ref->peer_ref->name);
 				ret = -2;
 				continue;
 			}
 		}
 		memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
 		if (is_zero_sha1(ref->new_sha1)) {
 			error("cannot happen anymore");
 			ret = -3;
 			continue;
 		}
 		new_refs++;
 		strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 		new_hex = sha1_to_hex(ref->new_sha1);
 		packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
 		fprintf(stderr, "updating '%s'", ref->name);
 		if (strcmp(ref->name, ref->peer_ref->name))
 			fprintf(stderr, " using '%s'", ref->peer_ref->name);
 		fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
 	}

 	packet_flush(out);
 	if (new_refs)
 		pack_objects(out, remote_refs);
 	else if (ret == 0)
 		fprintf(stderr, "Everything up-to-date\n");
 	close(out);
 	return ret;
 }


 int main(int argc, char **argv)
 {
 	int i, nr_heads = 0;
 	char *dest = NULL;
 	char **heads = NULL;
 	int fd[2], ret;
 	pid_t pid;

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

 		if (*arg == '-') {
 			if (!strncmp(arg, "--exec=", 7)) {
 				exec = arg + 7;
 				continue;
 			}
 			if (!strcmp(arg, "--all")) {
 				send_all = 1;
 				continue;
 			}
 			if (!strcmp(arg, "--force")) {
 				force_update = 1;
 				continue;
 			}
 			if (!strcmp(arg, "--verbose")) {
 				verbose = 1;
 				continue;
 			}
 			usage(send_pack_usage);
 		}
 		if (!dest) {
 			dest = arg;
 			continue;
 		}
 		heads = argv;
 		nr_heads = argc - i;
 		break;
 	}
 	if (!dest)
 		usage(send_pack_usage);
 	if (heads && send_all)
 		usage(send_pack_usage);
 	pid = git_connect(fd, dest, exec);
 	if (pid < 0)
 		return 1;
 	ret = send_pack(fd[0], fd[1], nr_heads, heads);
 	close(fd[0]);
 	close(fd[1]);
 	finish_connect(pid);
 	return ret;
 }
	#include "cache.h"
	#include "commit.h"
	#include "tag.h"
	#include "refs.h"
	#include "pkt-line.h"

	static const char send_pack_usage[] =
	"git-send-pack [--all] [--exec=git-receive-pack] <remote> [<head>...]\n"
	" --all and explicit <head> specification are mutually exclusive.";
	static const char *exec = "git-receive-pack";
	static int verbose = 0;
	static int send_all = 0;
	static int force_update = 0;

	static int is_zero_sha1(const unsigned char *sha1)
	{
	int i;

	for (i = 0; i < 20; i++) {
	if (*sha1++)
	return 0;
	}
	return 1;
	}

	static void exec_pack_objects(void)
	{
	static char *args[] = {
	"git-pack-objects",
	"--stdout",
	NULL
	};
	execvp("git-pack-objects", args);
	die("git-pack-objects exec failed (%s)", strerror(errno));
	}

	static void exec_rev_list(struct ref *refs)
	{
	static char *args[1000];
	int i = 0;

	args[i++] = "git-rev-list"; /* 0 */
	args[i++] = "--objects"; /* 1 */
	while (refs) {
	char *buf = malloc(100);
	if (i > 900)
	die("git-rev-list environment overflow");
	if (!is_zero_sha1(refs->old_sha1) &&
	has_sha1_file(refs->old_sha1)) {
	args[i++] = buf;
	snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
	buf += 50;
	}
	if (!is_zero_sha1(refs->new_sha1)) {
	args[i++] = buf;
	snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
	}
	refs = refs->next;
	}
	args[i] = NULL;
	execvp("git-rev-list", args);
	die("git-rev-list exec failed (%s)", strerror(errno));
	}

	static void rev_list(int fd, struct ref *refs)
	{
	int pipe_fd[2];
	pid_t pack_objects_pid;

	if (pipe(pipe_fd) < 0)
	die("rev-list setup: pipe failed");
	pack_objects_pid = fork();
	if (!pack_objects_pid) {
	dup2(pipe_fd[0], 0);
	dup2(fd, 1);
	close(pipe_fd[0]);
	close(pipe_fd[1]);
	close(fd);
	exec_pack_objects();
	die("pack-objects setup failed");
	}
	if (pack_objects_pid < 0)
	die("pack-objects fork failed");
	dup2(pipe_fd[1], 1);
	close(pipe_fd[0]);
	close(pipe_fd[1]);
	close(fd);
	exec_rev_list(refs);
	}

	static int pack_objects(int fd, struct ref *refs)
	{
	pid_t rev_list_pid;

	rev_list_pid = fork();
	if (!rev_list_pid) {
	rev_list(fd, refs);
	die("rev-list setup failed");
	}
	if (rev_list_pid < 0)
	die("rev-list fork failed");
	/*
	* We don't wait for the rev-list pipeline in the parent:
	* we end up waiting for the other end instead
	*/
	return 0;
	}

	static void unmark_and_free(struct commit_list *list, unsigned int mark)
	{
	while (list) {
	struct commit_list *temp = list;
	temp->item->object.flags &= ~mark;
	list = temp->next;
	free(temp);
	}
	}

	static int ref_newer(const unsigned char *new_sha1,
	const unsigned char *old_sha1)
	{
	struct object *o;
	struct commit old, new;
	struct commit_list list, used;
	int found = 0;

	/* Both new and old must be commit-ish and new is descendant of
	* old. Otherwise we require --force.
	*/
	o = deref_tag(parse_object(old_sha1), NULL, 0);
	if (!o \|\| o->type != commit_type)
	return 0;
	old = (struct commit *) o;

	o = deref_tag(parse_object(new_sha1), NULL, 0);
	if (!o \|\| o->type != commit_type)
	return 0;
	new = (struct commit *) o;

	if (parse_commit(new) < 0)
	return 0;

	used = list = NULL;
	commit_list_insert(new, &list);
	while (list) {
	new = pop_most_recent_commit(&list, 1);
	commit_list_insert(new, &used);
	if (new == old) {
	found = 1;
	break;
	}
	}
	unmark_and_free(list, 1);
	unmark_and_free(used, 1);
	return found;
	}

	static struct ref local_refs, *local_tail;
	static struct ref remote_refs, *remote_tail;

	static int one_local_ref(const char refname, const unsigned char sha1)
	{
	struct ref *ref;
	int len = strlen(refname) + 1;
	ref = xcalloc(1, sizeof(*ref) + len);
	memcpy(ref->new_sha1, sha1, 20);
	memcpy(ref->name, refname, len);
	*local_tail = ref;
	local_tail = &ref->next;
	return 0;
	}

	static void get_local_heads(void)
	{
	local_tail = &local_refs;
	for_each_ref(one_local_ref);
	}

	static int send_pack(int in, int out, int nr_refspec, char **refspec)
	{
	struct ref *ref;
	int new_refs;
	int ret = 0;

	/* No funny business with the matcher */
	remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, 1);
	get_local_heads();

	/* match them up */
	if (!remote_tail)
	remote_tail = &remote_refs;
	if (match_refs(local_refs, remote_refs, &remote_tail,
	nr_refspec, refspec, send_all))
	return -1;

	if (!remote_refs) {
	fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
	return 0;
	}

	/*
	* Finally, tell the other end!
	*/
	new_refs = 0;
	for (ref = remote_refs; ref; ref = ref->next) {
	char old_hex[60], *new_hex;
	if (!ref->peer_ref)
	continue;
	if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
	if (verbose)
	fprintf(stderr, "'%s': up-to-date\n", ref->name);
	continue;
	}

	/* This part determines what can overwrite what.
	* The rules are:
	*
	* (0) you can always use --force or +A:B notation to
	* selectively force individual ref pairs.
	*
	* (1) if the old thing does not exist, it is OK.
	*
	* (2) if you do not have the old thing, you are not allowed
	* to overwrite it; you would not know what you are losing
	* otherwise.
	*
	* (3) if both new and old are commit-ish, and new is a
	* descendant of old, it is OK.
	*/

	if (!force_update &&
	!is_zero_sha1(ref->old_sha1) &&
	!ref->force) {
	if (!has_sha1_file(ref->old_sha1)) {
	error("remote '%s' object %s does not "
	"exist on local",
	ref->name, sha1_to_hex(ref->old_sha1));
	ret = -2;
	continue;
	}

	/* We assume that local is fsck-clean. Otherwise
	* you _could_ have an old tag which points at
	* something you do not have, which may or may not
	* be a commit.
	*/
	if (!ref_newer(ref->peer_ref->new_sha1,
	ref->old_sha1)) {
	error("remote ref '%s' is not a strict "
	"subset of local ref '%s'.", ref->name,
	ref->peer_ref->name);
	ret = -2;
	continue;
	}
	}
	memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
	if (is_zero_sha1(ref->new_sha1)) {
	error("cannot happen anymore");
	ret = -3;
	continue;
	}
	new_refs++;
	strcpy(old_hex, sha1_to_hex(ref->old_sha1));
	new_hex = sha1_to_hex(ref->new_sha1);
	packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
	fprintf(stderr, "updating '%s'", ref->name);
	if (strcmp(ref->name, ref->peer_ref->name))
	fprintf(stderr, " using '%s'", ref->peer_ref->name);
	fprintf(stderr, "\n from %s\n to %s\n", old_hex, new_hex);
	}

	packet_flush(out);
	if (new_refs)
	pack_objects(out, remote_refs);
	else if (ret == 0)
	fprintf(stderr, "Everything up-to-date\n");
	close(out);
	return ret;
	}


	int main(int argc, char **argv)
	{
	int i, nr_heads = 0;
	char *dest = NULL;
	char **heads = NULL;
	int fd[2], ret;
	pid_t pid;

	setup_git_directory();
	argv++;
	for (i = 1; i < argc; i++, argv++) {
	char arg = argv;

	if (*arg == '-') {
	if (!strncmp(arg, "--exec=", 7)) {
	exec = arg + 7;
	continue;
	}
	if (!strcmp(arg, "--all")) {
	send_all = 1;
	continue;
	}
	if (!strcmp(arg, "--force")) {
	force_update = 1;
	continue;
	}
	if (!strcmp(arg, "--verbose")) {
	verbose = 1;
	continue;
	}
	usage(send_pack_usage);
	}
	if (!dest) {
	dest = arg;
	continue;
	}
	heads = argv;
	nr_heads = argc - i;
	break;
	}
	if (!dest)
	usage(send_pack_usage);
	if (heads && send_all)
	usage(send_pack_usage);
	pid = git_connect(fd, dest, exec);
	if (pid < 0)
	return 1;
	ret = send_pack(fd[0], fd[1], nr_heads, heads);
	close(fd[0]);
	close(fd[1]);
	finish_connect(pid);
	return ret;
	}