[thirdparty/git.git] / builtin-tar-tree.c

/*
 * Copyright (c) 2005, 2006 Rene Scharfe
 */
#include <time.h>
#include "cache.h"
#include "tree-walk.h"
#include "commit.h"
#include "strbuf.h"
#include "tar.h"
#include "builtin.h"
#include "pkt-line.h"

#define RECORDSIZE	(512)
#define BLOCKSIZE	(RECORDSIZE * 20)

static const char tar_tree_usage[] =
"git-tar-tree [--remote=<repo>] <ent> [basedir]";

static char block[BLOCKSIZE];
static unsigned long offset;

static time_t archive_time;

/* tries hard to write, either succeeds or dies in the attempt */
static void reliable_write(const void *data, unsigned long size)
{
	const char *buf = data;

	while (size > 0) {
		long ret = xwrite(1, buf, size);
		if (ret < 0) {
			if (errno == EPIPE)
				exit(0);
			die("git-tar-tree: %s", strerror(errno));
		} else if (!ret) {
			die("git-tar-tree: disk full?");
		}
		size -= ret;
		buf += ret;
	}
}

/* writes out the whole block, but only if it is full */
static void write_if_needed(void)
{
	if (offset == BLOCKSIZE) {
		reliable_write(block, BLOCKSIZE);
		offset = 0;
	}
}

/*
 * queues up writes, so that all our write(2) calls write exactly one
 * full block; pads writes to RECORDSIZE
 */
static void write_blocked(const void *data, unsigned long size)
{
	const char *buf = data;
	unsigned long tail;

	if (offset) {
		unsigned long chunk = BLOCKSIZE - offset;
		if (size < chunk)
			chunk = size;
		memcpy(block + offset, buf, chunk);
		size -= chunk;
		offset += chunk;
		buf += chunk;
		write_if_needed();
	}
	while (size >= BLOCKSIZE) {
		reliable_write(buf, BLOCKSIZE);
		size -= BLOCKSIZE;
		buf += BLOCKSIZE;
	}
	if (size) {
		memcpy(block + offset, buf, size);
		offset += size;
	}
	tail = offset % RECORDSIZE;
	if (tail)  {
		memset(block + offset, 0, RECORDSIZE - tail);
		offset += RECORDSIZE - tail;
	}
	write_if_needed();
}

/*
 * The end of tar archives is marked by 2*512 nul bytes and after that
 * follows the rest of the block (if any).
 */
static void write_trailer(void)
{
	int tail = BLOCKSIZE - offset;
	memset(block + offset, 0, tail);
	reliable_write(block, BLOCKSIZE);
	if (tail < 2 * RECORDSIZE) {
		memset(block, 0, offset);
		reliable_write(block, BLOCKSIZE);
	}
}

static void strbuf_append_string(struct strbuf *sb, const char *s)
{
	int slen = strlen(s);
	int total = sb->len + slen;
	if (total > sb->alloc) {
		sb->buf = xrealloc(sb->buf, total);
		sb->alloc = total;
	}
	memcpy(sb->buf + sb->len, s, slen);
	sb->len = total;
}

/*
 * pax extended header records have the format "%u %s=%s\n".  %u contains
 * the size of the whole string (including the %u), the first %s is the
 * keyword, the second one is the value.  This function constructs such a
 * string and appends it to a struct strbuf.
 */
static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
                                     const char *value, unsigned int valuelen)
{
	char *p;
	int len, total, tmp;

	/* "%u %s=%s\n" */
	len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
	for (tmp = len; tmp > 9; tmp /= 10)
		len++;

	total = sb->len + len;
	if (total > sb->alloc) {
		sb->buf = xrealloc(sb->buf, total);
		sb->alloc = total;
	}

	p = sb->buf;
	p += sprintf(p, "%u %s=", len, keyword);
	memcpy(p, value, valuelen);
	p += valuelen;
	*p = '\n';
	sb->len = total;
}

static unsigned int ustar_header_chksum(const struct ustar_header *header)
{
	char *p = (char *)header;
	unsigned int chksum = 0;
	while (p < header->chksum)
		chksum += *p++;
	chksum += sizeof(header->chksum) * ' ';
	p += sizeof(header->chksum);
	while (p < (char *)header + sizeof(struct ustar_header))
		chksum += *p++;
	return chksum;
}

static int get_path_prefix(const struct strbuf *path, int maxlen)
{
	int i = path->len;
	if (i > maxlen)
		i = maxlen;
	do {
		i--;
	} while (i > 0 && path->buf[i] != '/');
	return i;
}

static void write_entry(const unsigned char *sha1, struct strbuf *path,
                        unsigned int mode, void *buffer, unsigned long size)
{
	struct ustar_header header;
	struct strbuf ext_header;

	memset(&header, 0, sizeof(header));
	ext_header.buf = NULL;
	ext_header.len = ext_header.alloc = 0;

	if (!sha1) {
		*header.typeflag = TYPEFLAG_GLOBAL_HEADER;
		mode = 0100666;
		strcpy(header.name, "pax_global_header");
	} else if (!path) {
		*header.typeflag = TYPEFLAG_EXT_HEADER;
		mode = 0100666;
		sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
	} else {
		if (S_ISDIR(mode)) {
			*header.typeflag = TYPEFLAG_DIR;
			mode |= 0777;
		} else if (S_ISLNK(mode)) {
			*header.typeflag = TYPEFLAG_LNK;
			mode |= 0777;
		} else if (S_ISREG(mode)) {
			*header.typeflag = TYPEFLAG_REG;
			mode |= (mode & 0100) ? 0777 : 0666;
		} else {
			error("unsupported file mode: 0%o (SHA1: %s)",
			      mode, sha1_to_hex(sha1));
			return;
		}
		if (path->len > sizeof(header.name)) {
			int plen = get_path_prefix(path, sizeof(header.prefix));
			int rest = path->len - plen - 1;
			if (plen > 0 && rest <= sizeof(header.name)) {
				memcpy(header.prefix, path->buf, plen);
				memcpy(header.name, path->buf + plen + 1, rest);
			} else {
				sprintf(header.name, "%s.data",
				        sha1_to_hex(sha1));
				strbuf_append_ext_header(&ext_header, "path",
				                         path->buf, path->len);
			}
		} else
			memcpy(header.name, path->buf, path->len);
	}

	if (S_ISLNK(mode) && buffer) {
		if (size > sizeof(header.linkname)) {
			sprintf(header.linkname, "see %s.paxheader",
			        sha1_to_hex(sha1));
			strbuf_append_ext_header(&ext_header, "linkpath",
			                         buffer, size);
		} else
			memcpy(header.linkname, buffer, size);
	}

	sprintf(header.mode, "%07o", mode & 07777);
	sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0);
	sprintf(header.mtime, "%011lo", archive_time);

	/* XXX: should we provide more meaningful info here? */
	sprintf(header.uid, "%07o", 0);
	sprintf(header.gid, "%07o", 0);
	strlcpy(header.uname, "git", sizeof(header.uname));
	strlcpy(header.gname, "git", sizeof(header.gname));
	sprintf(header.devmajor, "%07o", 0);
	sprintf(header.devminor, "%07o", 0);

	memcpy(header.magic, "ustar", 6);
	memcpy(header.version, "00", 2);

	sprintf(header.chksum, "%07o", ustar_header_chksum(&header));

	if (ext_header.len > 0) {
		write_entry(sha1, NULL, 0, ext_header.buf, ext_header.len);
		free(ext_header.buf);
	}
	write_blocked(&header, sizeof(header));
	if (S_ISREG(mode) && buffer && size > 0)
		write_blocked(buffer, size);
}

static void write_global_extended_header(const unsigned char *sha1)
{
	struct strbuf ext_header;
	ext_header.buf = NULL;
	ext_header.len = ext_header.alloc = 0;
	strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
	write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len);
	free(ext_header.buf);
}

static void traverse_tree(struct tree_desc *tree, struct strbuf *path)
{
	int pathlen = path->len;
	struct name_entry entry;

	while (tree_entry(tree, &entry)) {
		void *eltbuf;
		char elttype[20];
		unsigned long eltsize;

		eltbuf = read_sha1_file(entry.sha1, elttype, &eltsize);
		if (!eltbuf)
			die("cannot read %s", sha1_to_hex(entry.sha1));

		path->len = pathlen;
		strbuf_append_string(path, entry.path);
		if (S_ISDIR(entry.mode))
			strbuf_append_string(path, "/");

		write_entry(entry.sha1, path, entry.mode, eltbuf, eltsize);

		if (S_ISDIR(entry.mode)) {
			struct tree_desc subtree;
			subtree.buf = eltbuf;
			subtree.size = eltsize;
			traverse_tree(&subtree, path);
		}
		free(eltbuf);
	}
}

static int generate_tar(int argc, const char **argv, char** envp)
{
	unsigned char sha1[20], tree_sha1[20];
	struct commit *commit;
	struct tree_desc tree;
	struct strbuf current_path;

	current_path.buf = xmalloc(PATH_MAX);
	current_path.alloc = PATH_MAX;
	current_path.len = current_path.eof = 0;

	setup_git_directory();
	git_config(git_default_config);

	switch (argc) {
	case 3:
		strbuf_append_string(&current_path, argv[2]);
		strbuf_append_string(&current_path, "/");
		/* FALLTHROUGH */
	case 2:
		if (get_sha1(argv[1], sha1))
			die("Not a valid object name %s", argv[1]);
		break;
	default:
		usage(tar_tree_usage);
	}

	commit = lookup_commit_reference_gently(sha1, 1);
	if (commit) {
		write_global_extended_header(commit->object.sha1);
		archive_time = commit->date;
	} else
		archive_time = time(NULL);

	tree.buf = read_object_with_reference(sha1, tree_type, &tree.size,
	                                      tree_sha1);
	if (!tree.buf)
		die("not a reference to a tag, commit or tree object: %s",
		    sha1_to_hex(sha1));

	if (current_path.len > 0)
		write_entry(tree_sha1, &current_path, 040777, NULL, 0);
	traverse_tree(&tree, &current_path);
	write_trailer();
	free(current_path.buf);
	return 0;
}

static const char *exec = "git-upload-tar";

static int remote_tar(int argc, const char **argv)
{
	int fd[2], ret, len;
	pid_t pid;
	char buf[1024];
	char *url;

	if (argc < 3 || 4 < argc)
		usage(tar_tree_usage);

	/* --remote=<repo> */
	url = strdup(argv[1]+9);
	pid = git_connect(fd, url, exec);
	if (pid < 0)
		return 1;

	packet_write(fd[1], "want %s\n", argv[2]);
	if (argv[3])
		packet_write(fd[1], "base %s\n", argv[3]);
	packet_flush(fd[1]);

	len = packet_read_line(fd[0], buf, sizeof(buf));
	if (!len)
		die("git-tar-tree: expected ACK/NAK, got EOF");
	if (buf[len-1] == '\n')
		buf[--len] = 0;
	if (strcmp(buf, "ACK")) {
		if (5 < len && !strncmp(buf, "NACK ", 5))
			die("git-tar-tree: NACK %s", buf + 5);
		die("git-tar-tree: protocol error");
	}
	/* expect a flush */
	len = packet_read_line(fd[0], buf, sizeof(buf));
	if (len)
		die("git-tar-tree: expected a flush");

	/* Now, start reading from fd[0] and spit it out to stdout */
	ret = copy_fd(fd[0], 1);
	close(fd[0]);

	ret |= finish_connect(pid);
	return !!ret;
}

int cmd_tar_tree(int argc, const char **argv, char **envp)
{
	if (argc < 2)
		usage(tar_tree_usage);
	if (!strncmp("--remote=", argv[1], 9))
		return remote_tar(argc, argv);
	return generate_tar(argc, argv, envp);
}

/* ustar header + extended global header content */
#define HEADERSIZE (2 * RECORDSIZE)

int cmd_get_tar_commit_id(int argc, const char **argv, char **envp)
{
	char buffer[HEADERSIZE];
	struct ustar_header *header = (struct ustar_header *)buffer;
	char *content = buffer + RECORDSIZE;
	ssize_t n;

	n = xread(0, buffer, HEADERSIZE);
	if (n < HEADERSIZE)
		die("git-get-tar-commit-id: read error");
	if (header->typeflag[0] != 'g')
		return 1;
	if (memcmp(content, "52 comment=", 11))
		return 1;

	n = xwrite(1, content + 11, 41);
	if (n < 41)
		die("git-get-tar-commit-id: write error");

	return 0;
}
Commit	Line	Data
92747a90	1	/*
ae64bbc1	2	* Copyright (c) 2005, 2006 Rene Scharfe
92747a90	3	*/
731ab9cc RS	4	#include <time.h>
731ab9cc RS	5	#include "cache.h"
1b0c7174	6	#include "tree-walk.h"
c3f92812	7	#include "commit.h"
ae64bbc1 RS	8	#include "strbuf.h"
ae64bbc1 RS	9	#include "tar.h"
56d1398a	10	#include "builtin.h"
21754264	11	#include "pkt-line.h"
731ab9cc RS	12
	13	#define RECORDSIZE (512)
	14	#define BLOCKSIZE (RECORDSIZE * 20)
	15
21754264 JH	16	static const char tar_tree_usage[] =
21754264 JH	17	"git-tar-tree [--remote=<repo>] <ent> [basedir]";
731ab9cc RS	18
	19	static char block[BLOCKSIZE];
	20	static unsigned long offset;
	21
731ab9cc RS	22	static time_t archive_time;
731ab9cc RS	23
731ab9cc	24	/* tries hard to write, either succeeds or dies in the attempt */
6698060c	25	static void reliable_write(const void *data, unsigned long size)
731ab9cc	26	{
6698060c RS	27	const char *buf = data;
6698060c RS	28
731ab9cc	29	while (size > 0) {
1c15afb9	30	long ret = xwrite(1, buf, size);
731ab9cc	31	if (ret < 0) {
731ab9cc RS	32	if (errno == EPIPE)
731ab9cc RS	33	exit(0);
667bb59b	34	die("git-tar-tree: %s", strerror(errno));
731ab9cc	35	} else if (!ret) {
667bb59b	36	die("git-tar-tree: disk full?");
731ab9cc RS	37	}
	38	size -= ret;
	39	buf += ret;
	40	}
	41	}
	42
	43	/* writes out the whole block, but only if it is full */
	44	static void write_if_needed(void)
	45	{
	46	if (offset == BLOCKSIZE) {
	47	reliable_write(block, BLOCKSIZE);
	48	offset = 0;
	49	}
	50	}
	51
731ab9cc RS	52	/*
	53	* queues up writes, so that all our write(2) calls write exactly one
	54	* full block; pads writes to RECORDSIZE
	55	*/
6698060c	56	static void write_blocked(const void *data, unsigned long size)
731ab9cc	57	{
6698060c	58	const char *buf = data;
731ab9cc RS	59	unsigned long tail;
	60
	61	if (offset) {
	62	unsigned long chunk = BLOCKSIZE - offset;
	63	if (size < chunk)
	64	chunk = size;
	65	memcpy(block + offset, buf, chunk);
	66	size -= chunk;
	67	offset += chunk;
	68	buf += chunk;
	69	write_if_needed();
	70	}
	71	while (size >= BLOCKSIZE) {
	72	reliable_write(buf, BLOCKSIZE);
	73	size -= BLOCKSIZE;
	74	buf += BLOCKSIZE;
	75	}
	76	if (size) {
	77	memcpy(block + offset, buf, size);
731ab9cc RS	78	offset += size;
	79	}
	80	tail = offset % RECORDSIZE;
	81	if (tail) {
	82	memset(block + offset, 0, RECORDSIZE - tail);
	83	offset += RECORDSIZE - tail;
	84	}
	85	write_if_needed();
	86	}
	87
37958be7 RS	88	/*
	89	* The end of tar archives is marked by 2*512 nul bytes and after that
	90	* follows the rest of the block (if any).
	91	*/
	92	static void write_trailer(void)
	93	{
	94	int tail = BLOCKSIZE - offset;
	95	memset(block + offset, 0, tail);
	96	reliable_write(block, BLOCKSIZE);
	97	if (tail < 2 * RECORDSIZE) {
	98	memset(block, 0, offset);
	99	reliable_write(block, BLOCKSIZE);
	100	}
	101	}
	102
cb0c6df6	103	static void strbuf_append_string(struct strbuf sb, const char s)
731ab9cc	104	{
cb0c6df6 RS	105	int slen = strlen(s);
	106	int total = sb->len + slen;
	107	if (total > sb->alloc) {
	108	sb->buf = xrealloc(sb->buf, total);
	109	sb->alloc = total;
731ab9cc	110	}
cb0c6df6 RS	111	memcpy(sb->buf + sb->len, s, slen);
cb0c6df6 RS	112	sb->len = total;
731ab9cc RS	113	}
731ab9cc RS	114
ae64bbc1 RS	115	/*
	116	* pax extended header records have the format "%u %s=%s\n". %u contains
	117	* the size of the whole string (including the %u), the first %s is the
	118	* keyword, the second one is the value. This function constructs such a
	119	* string and appends it to a struct strbuf.
	120	*/
	121	static void strbuf_append_ext_header(struct strbuf sb, const char keyword,
	122	const char *value, unsigned int valuelen)
71058b1f	123	{
ae64bbc1 RS	124	char *p;
ae64bbc1 RS	125	int len, total, tmp;
71058b1f	126
71058b1f	127	/* "%u %s=%s\n" */
ae64bbc1 RS	128	len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
ae64bbc1 RS	129	for (tmp = len; tmp > 9; tmp /= 10)
71058b1f	130	len++;
71058b1f	131
ae64bbc1 RS	132	total = sb->len + len;
	133	if (total > sb->alloc) {
	134	sb->buf = xrealloc(sb->buf, total);
	135	sb->alloc = total;
	136	}
71058b1f	137
ae64bbc1 RS	138	p = sb->buf;
	139	p += sprintf(p, "%u %s=", len, keyword);
	140	memcpy(p, value, valuelen);
	141	p += valuelen;
	142	*p = '\n';
	143	sb->len = total;
	144	}
731ab9cc	145
ae64bbc1	146	static unsigned int ustar_header_chksum(const struct ustar_header *header)
731ab9cc	147	{
ae64bbc1 RS	148	char p = (char )header;
	149	unsigned int chksum = 0;
	150	while (p < header->chksum)
	151	chksum += *p++;
	152	chksum += sizeof(header->chksum) * ' ';
	153	p += sizeof(header->chksum);
	154	while (p < (char *)header + sizeof(struct ustar_header))
	155	chksum += *p++;
	156	return chksum;
731ab9cc RS	157	}
731ab9cc RS	158
4c691724	159	static int get_path_prefix(const struct strbuf *path, int maxlen)
87fec8fc	160	{
4c691724 RS	161	int i = path->len;
	162	if (i > maxlen)
	163	i = maxlen;
17cf250a	164	do {
4c691724	165	i--;
17cf250a	166	} while (i > 0 && path->buf[i] != '/');
4c691724	167	return i;
87fec8fc RS	168	}
87fec8fc RS	169
ae64bbc1 RS	170	static void write_entry(const unsigned char sha1, struct strbuf path,
ae64bbc1 RS	171	unsigned int mode, void *buffer, unsigned long size)
731ab9cc	172	{
ae64bbc1 RS	173	struct ustar_header header;
	174	struct strbuf ext_header;
	175
	176	memset(&header, 0, sizeof(header));
	177	ext_header.buf = NULL;
	178	ext_header.len = ext_header.alloc = 0;
	179
	180	if (!sha1) {
	181	*header.typeflag = TYPEFLAG_GLOBAL_HEADER;
	182	mode = 0100666;
	183	strcpy(header.name, "pax_global_header");
	184	} else if (!path) {
	185	*header.typeflag = TYPEFLAG_EXT_HEADER;
	186	mode = 0100666;
	187	sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
731ab9cc	188	} else {
ae64bbc1 RS	189	if (S_ISDIR(mode)) {
	190	*header.typeflag = TYPEFLAG_DIR;
	191	mode \|= 0777;
	192	} else if (S_ISLNK(mode)) {
	193	*header.typeflag = TYPEFLAG_LNK;
	194	mode \|= 0777;
	195	} else if (S_ISREG(mode)) {
	196	*header.typeflag = TYPEFLAG_REG;
	197	mode \|= (mode & 0100) ? 0777 : 0666;
	198	} else {
	199	error("unsupported file mode: 0%o (SHA1: %s)",
	200	mode, sha1_to_hex(sha1));
	201	return;
	202	}
	203	if (path->len > sizeof(header.name)) {
4c691724 RS	204	int plen = get_path_prefix(path, sizeof(header.prefix));
	205	int rest = path->len - plen - 1;
	206	if (plen > 0 && rest <= sizeof(header.name)) {
	207	memcpy(header.prefix, path->buf, plen);
	208	memcpy(header.name, path->buf + plen + 1, rest);
	209	} else {
	210	sprintf(header.name, "%s.data",
	211	sha1_to_hex(sha1));
	212	strbuf_append_ext_header(&ext_header, "path",
	213	path->buf, path->len);
	214	}
ae64bbc1 RS	215	} else
ae64bbc1 RS	216	memcpy(header.name, path->buf, path->len);
731ab9cc RS	217	}
731ab9cc RS	218
ae64bbc1 RS	219	if (S_ISLNK(mode) && buffer) {
	220	if (size > sizeof(header.linkname)) {
	221	sprintf(header.linkname, "see %s.paxheader",
d5776d50	222	sha1_to_hex(sha1));
ae64bbc1 RS	223	strbuf_append_ext_header(&ext_header, "linkpath",
	224	buffer, size);
	225	} else
	226	memcpy(header.linkname, buffer, size);
d5776d50 RS	227	}
d5776d50 RS	228
ae64bbc1 RS	229	sprintf(header.mode, "%07o", mode & 07777);
	230	sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0);
	231	sprintf(header.mtime, "%011lo", archive_time);
731ab9cc RS	232
731ab9cc RS	233	/* XXX: should we provide more meaningful info here? */
ae64bbc1 RS	234	sprintf(header.uid, "%07o", 0);
ae64bbc1 RS	235	sprintf(header.gid, "%07o", 0);
817151e6 PE	236	strlcpy(header.uname, "git", sizeof(header.uname));
817151e6 PE	237	strlcpy(header.gname, "git", sizeof(header.gname));
ae64bbc1 RS	238	sprintf(header.devmajor, "%07o", 0);
ae64bbc1 RS	239	sprintf(header.devminor, "%07o", 0);
731ab9cc	240
ae64bbc1 RS	241	memcpy(header.magic, "ustar", 6);
ae64bbc1 RS	242	memcpy(header.version, "00", 2);
731ab9cc	243
ae64bbc1	244	sprintf(header.chksum, "%07o", ustar_header_chksum(&header));
731ab9cc	245
ae64bbc1 RS	246	if (ext_header.len > 0) {
	247	write_entry(sha1, NULL, 0, ext_header.buf, ext_header.len);
	248	free(ext_header.buf);
	249	}
	250	write_blocked(&header, sizeof(header));
	251	if (S_ISREG(mode) && buffer && size > 0)
	252	write_blocked(buffer, size);
	253	}
731ab9cc	254
bf0f910d	255	static void write_global_extended_header(const unsigned char *sha1)
87fec8fc	256	{
ae64bbc1 RS	257	struct strbuf ext_header;
	258	ext_header.buf = NULL;
	259	ext_header.len = ext_header.alloc = 0;
	260	strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
	261	write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len);
	262	free(ext_header.buf);
731ab9cc RS	263	}
731ab9cc RS	264
cb0c6df6	265	static void traverse_tree(struct tree_desc tree, struct strbuf path)
731ab9cc	266	{
cb0c6df6	267	int pathlen = path->len;
4c068a98	268	struct name_entry entry;
731ab9cc	269
4c068a98	270	while (tree_entry(tree, &entry)) {
731ab9cc RS	271	void *eltbuf;
	272	char elttype[20];
	273	unsigned long eltsize;
5207234a	274
4c068a98	275	eltbuf = read_sha1_file(entry.sha1, elttype, &eltsize);
731ab9cc	276	if (!eltbuf)
4c068a98	277	die("cannot read %s", sha1_to_hex(entry.sha1));
cb0c6df6 RS	278
cb0c6df6 RS	279	path->len = pathlen;
4c068a98 LT	280	strbuf_append_string(path, entry.path);
4c068a98 LT	281	if (S_ISDIR(entry.mode))
cb0c6df6 RS	282	strbuf_append_string(path, "/");
cb0c6df6 RS	283
4c068a98	284	write_entry(entry.sha1, path, entry.mode, eltbuf, eltsize);
cb0c6df6	285
4c068a98	286	if (S_ISDIR(entry.mode)) {
7ec57556 LT	287	struct tree_desc subtree;
	288	subtree.buf = eltbuf;
	289	subtree.size = eltsize;
cb0c6df6	290	traverse_tree(&subtree, path);
731ab9cc RS	291	}
	292	free(eltbuf);
	293	}
	294	}
	295
1af0d112	296	static int generate_tar(int argc, const char argv, char envp)
731ab9cc	297	{
2c6df2d5	298	unsigned char sha1[20], tree_sha1[20];
c3f92812	299	struct commit *commit;
7ec57556	300	struct tree_desc tree;
cb0c6df6 RS	301	struct strbuf current_path;
	302
	303	current_path.buf = xmalloc(PATH_MAX);
	304	current_path.alloc = PATH_MAX;
	305	current_path.len = current_path.eof = 0;
731ab9cc	306
53228a5f	307	setup_git_directory();
84a9b58c	308	git_config(git_default_config);
53228a5f	309
731ab9cc RS	310	switch (argc) {
731ab9cc RS	311	case 3:
cb0c6df6 RS	312	strbuf_append_string(&current_path, argv[2]);
cb0c6df6 RS	313	strbuf_append_string(&current_path, "/");
731ab9cc RS	314	/* FALLTHROUGH */
731ab9cc RS	315	case 2:
31fff305 DL	316	if (get_sha1(argv[1], sha1))
31fff305 DL	317	die("Not a valid object name %s", argv[1]);
731ab9cc RS	318	break;
	319	default:
	320	usage(tar_tree_usage);
	321	}
	322
473d404b	323	commit = lookup_commit_reference_gently(sha1, 1);
c3f92812 DB	324	if (commit) {
	325	write_global_extended_header(commit->object.sha1);
	326	archive_time = commit->date;
cb0c6df6 RS	327	} else
	328	archive_time = time(NULL);
	329
8e440259	330	tree.buf = read_object_with_reference(sha1, tree_type, &tree.size,
2c6df2d5	331	tree_sha1);
7ec57556	332	if (!tree.buf)
db413479 RS	333	die("not a reference to a tag, commit or tree object: %s",
db413479 RS	334	sha1_to_hex(sha1));
cb0c6df6 RS	335
	336	if (current_path.len > 0)
	337	write_entry(tree_sha1, &current_path, 040777, NULL, 0);
	338	traverse_tree(&tree, &current_path);
731ab9cc	339	write_trailer();
cb0c6df6	340	free(current_path.buf);
731ab9cc RS	341	return 0;
731ab9cc RS	342	}
21754264 JH	343
	344	static const char *exec = "git-upload-tar";
	345
	346	static int remote_tar(int argc, const char **argv)
	347	{
	348	int fd[2], ret, len;
	349	pid_t pid;
	350	char buf[1024];
	351	char *url;
	352
	353	if (argc < 3 \|\| 4 < argc)
	354	usage(tar_tree_usage);
	355
	356	/* --remote=<repo> */
	357	url = strdup(argv[1]+9);
	358	pid = git_connect(fd, url, exec);
	359	if (pid < 0)
	360	return 1;
	361
	362	packet_write(fd[1], "want %s\n", argv[2]);
	363	if (argv[3])
	364	packet_write(fd[1], "base %s\n", argv[3]);
	365	packet_flush(fd[1]);
	366
	367	len = packet_read_line(fd[0], buf, sizeof(buf));
	368	if (!len)
	369	die("git-tar-tree: expected ACK/NAK, got EOF");
	370	if (buf[len-1] == '\n')
	371	buf[--len] = 0;
	372	if (strcmp(buf, "ACK")) {
	373	if (5 < len && !strncmp(buf, "NACK ", 5))
	374	die("git-tar-tree: NACK %s", buf + 5);
	375	die("git-tar-tree: protocol error");
	376	}
	377	/* expect a flush */
	378	len = packet_read_line(fd[0], buf, sizeof(buf));
	379	if (len)
	380	die("git-tar-tree: expected a flush");
	381
	382	/* Now, start reading from fd[0] and spit it out to stdout */
	383	ret = copy_fd(fd[0], 1);
	384	close(fd[0]);
	385
	386	ret \|= finish_connect(pid);
	387	return !!ret;
	388	}
	389
	390	int cmd_tar_tree(int argc, const char argv, char envp)
	391	{
	392	if (argc < 2)
	393	usage(tar_tree_usage);
	394	if (!strncmp("--remote=", argv[1], 9))
	395	return remote_tar(argc, argv);
1af0d112	396	return generate_tar(argc, argv, envp);
21754264	397	}
52ba03cb RS	398
	399	/* ustar header + extended global header content */
	400	#define HEADERSIZE (2 * RECORDSIZE)
	401
	402	int cmd_get_tar_commit_id(int argc, const char argv, char envp)
	403	{
	404	char buffer[HEADERSIZE];
	405	struct ustar_header header = (struct ustar_header )buffer;
	406	char *content = buffer + RECORDSIZE;
	407	ssize_t n;
	408
	409	n = xread(0, buffer, HEADERSIZE);
	410	if (n < HEADERSIZE)
	411	die("git-get-tar-commit-id: read error");
	412	if (header->typeflag[0] != 'g')
	413	return 1;
	414	if (memcmp(content, "52 comment=", 11))
	415	return 1;
	416
	417	n = xwrite(1, content + 11, 41);
	418	if (n < 41)
	419	die("git-get-tar-commit-id: write error");
	420
	421	return 0;
	422	}