[thirdparty/git.git] / archive-tar.c

/*
 * Copyright (c) 2005, 2006 Rene Scharfe
 */
#include "cache.h"
#include "commit.h"
#include "tar.h"
#include "builtin.h"
#include "archive.h"

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

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

static time_t archive_time;
static int tar_umask = 002;
static int verbose;
static const struct commit *commit;
static size_t base_len;

/* writes out the whole block, but only if it is full */
static void write_if_needed(void)
{
	if (offset == BLOCKSIZE) {
		write_or_die(1, 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) {
		write_or_die(1, 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);
	write_or_die(1, block, BLOCKSIZE);
	if (tail < 2 * RECORDSIZE) {
		memset(block, 0, offset);
		write_or_die(1, block, BLOCKSIZE);
	}
}

/*
 * 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)
{
	int len, tmp;

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

	strbuf_grow(sb, len);
	strbuf_addf(sb, "%u %s=", len, keyword);
	strbuf_add(sb, value, valuelen);
	strbuf_addch(sb, '\n');
}

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));
	strbuf_init(&ext_header, 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 (verbose)
			fprintf(stderr, "%.*s\n", (int)path->len, path->buf);
		if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
			*header.typeflag = TYPEFLAG_DIR;
			mode = (mode | 0777) & ~tar_umask;
		} else if (S_ISLNK(mode)) {
			*header.typeflag = TYPEFLAG_LNK;
			mode |= 0777;
		} else if (S_ISREG(mode)) {
			*header.typeflag = TYPEFLAG_REG;
			mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
		} 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);

	sprintf(header.uid, "%07o", 0);
	sprintf(header.gid, "%07o", 0);
	strlcpy(header.uname, "root", sizeof(header.uname));
	strlcpy(header.gname, "root", 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);
	}
	strbuf_release(&ext_header);
	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;

	strbuf_init(&ext_header, 0);
	strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
	write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len);
	strbuf_release(&ext_header);
}

static int git_tar_config(const char *var, const char *value)
{
	if (!strcmp(var, "tar.umask")) {
		if (value && !strcmp(value, "user")) {
			tar_umask = umask(0);
			umask(tar_umask);
		} else {
			tar_umask = git_config_int(var, value);
		}
		return 0;
	}
	return git_default_config(var, value);
}

static int write_tar_entry(const unsigned char *sha1,
                           const char *base, int baselen,
                           const char *filename, unsigned mode, int stage)
{
	static struct strbuf path = STRBUF_INIT;
	void *buffer;
	enum object_type type;
	unsigned long size;

	strbuf_reset(&path);
	strbuf_grow(&path, PATH_MAX);
	strbuf_add(&path, base, baselen);
	strbuf_addstr(&path, filename);
	if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
		strbuf_addch(&path, '/');
		buffer = NULL;
		size = 0;
	} else {
		buffer = sha1_file_to_archive(path.buf + base_len, sha1, mode,
				&type, &size, commit);
		if (!buffer)
			die("cannot read %s", sha1_to_hex(sha1));
	}

	write_entry(sha1, &path, mode, buffer, size);
	free(buffer);

	return READ_TREE_RECURSIVE;
}

int write_tar_archive(struct archiver_args *args)
{
	int plen = args->base ? strlen(args->base) : 0;

	git_config(git_tar_config);

	archive_time = args->time;
	verbose = args->verbose;
	commit = args->commit;
	base_len = args->base ? strlen(args->base) : 0;

	if (args->commit_sha1)
		write_global_extended_header(args->commit_sha1);

	if (args->base && plen > 0 && args->base[plen - 1] == '/') {
		char *base = xstrdup(args->base);
		int baselen = strlen(base);

		while (baselen > 0 && base[baselen - 1] == '/')
			base[--baselen] = '\0';
		write_tar_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
		free(base);
	}
	read_tree_recursive(args->tree, args->base, plen, 0,
			    args->pathspec, write_tar_entry);
	write_trailer();

	return 0;
}
Commit	Line	Data
3d74982f RS	1	/*
	2	* Copyright (c) 2005, 2006 Rene Scharfe
	3	*/
3d74982f RS	4	#include "cache.h"
3d74982f RS	5	#include "commit.h"
3d74982f RS	6	#include "tar.h"
	7	#include "builtin.h"
	8	#include "archive.h"
	9
	10	#define RECORDSIZE (512)
	11	#define BLOCKSIZE (RECORDSIZE * 20)
	12
	13	static char block[BLOCKSIZE];
	14	static unsigned long offset;
	15
	16	static time_t archive_time;
f08b3b0e	17	static int tar_umask = 002;
3d74982f	18	static int verbose;
8460b2fc	19	static const struct commit *commit;
ac7fa277	20	static size_t base_len;
3d74982f RS	21
	22	/* writes out the whole block, but only if it is full */
	23	static void write_if_needed(void)
	24	{
	25	if (offset == BLOCKSIZE) {
	26	write_or_die(1, block, BLOCKSIZE);
	27	offset = 0;
	28	}
	29	}
	30
	31	/*
	32	* queues up writes, so that all our write(2) calls write exactly one
	33	* full block; pads writes to RECORDSIZE
	34	*/
	35	static void write_blocked(const void *data, unsigned long size)
	36	{
	37	const char *buf = data;
	38	unsigned long tail;
	39
	40	if (offset) {
	41	unsigned long chunk = BLOCKSIZE - offset;
	42	if (size < chunk)
	43	chunk = size;
	44	memcpy(block + offset, buf, chunk);
	45	size -= chunk;
	46	offset += chunk;
	47	buf += chunk;
	48	write_if_needed();
	49	}
	50	while (size >= BLOCKSIZE) {
	51	write_or_die(1, buf, BLOCKSIZE);
	52	size -= BLOCKSIZE;
	53	buf += BLOCKSIZE;
	54	}
	55	if (size) {
	56	memcpy(block + offset, buf, size);
	57	offset += size;
	58	}
	59	tail = offset % RECORDSIZE;
	60	if (tail) {
	61	memset(block + offset, 0, RECORDSIZE - tail);
	62	offset += RECORDSIZE - tail;
	63	}
	64	write_if_needed();
	65	}
	66
	67	/*
	68	* The end of tar archives is marked by 2*512 nul bytes and after that
	69	* follows the rest of the block (if any).
	70	*/
	71	static void write_trailer(void)
	72	{
	73	int tail = BLOCKSIZE - offset;
	74	memset(block + offset, 0, tail);
	75	write_or_die(1, block, BLOCKSIZE);
	76	if (tail < 2 * RECORDSIZE) {
	77	memset(block, 0, offset);
	78	write_or_die(1, block, BLOCKSIZE);
	79	}
	80	}
	81
3d74982f RS	82	/*
	83	* pax extended header records have the format "%u %s=%s\n". %u contains
	84	* the size of the whole string (including the %u), the first %s is the
	85	* keyword, the second one is the value. This function constructs such a
	86	* string and appends it to a struct strbuf.
	87	*/
	88	static void strbuf_append_ext_header(struct strbuf sb, const char keyword,
	89	const char *value, unsigned int valuelen)
	90	{
7a604f16	91	int len, tmp;
3d74982f RS	92
	93	/* "%u %s=%s\n" */
	94	len = 1 + 1 + strlen(keyword) + 1 + valuelen + 1;
	95	for (tmp = len; tmp > 9; tmp /= 10)
	96	len++;
	97
7a604f16 PH	98	strbuf_grow(sb, len);
	99	strbuf_addf(sb, "%u %s=", len, keyword);
	100	strbuf_add(sb, value, valuelen);
	101	strbuf_addch(sb, '\n');
3d74982f RS	102	}
	103
	104	static unsigned int ustar_header_chksum(const struct ustar_header *header)
	105	{
	106	char p = (char )header;
	107	unsigned int chksum = 0;
	108	while (p < header->chksum)
	109	chksum += *p++;
	110	chksum += sizeof(header->chksum) * ' ';
	111	p += sizeof(header->chksum);
	112	while (p < (char *)header + sizeof(struct ustar_header))
	113	chksum += *p++;
	114	return chksum;
	115	}
	116
	117	static int get_path_prefix(const struct strbuf *path, int maxlen)
	118	{
	119	int i = path->len;
	120	if (i > maxlen)
	121	i = maxlen;
	122	do {
	123	i--;
	124	} while (i > 0 && path->buf[i] != '/');
	125	return i;
	126	}
	127
	128	static void write_entry(const unsigned char sha1, struct strbuf path,
	129	unsigned int mode, void *buffer, unsigned long size)
	130	{
	131	struct ustar_header header;
	132	struct strbuf ext_header;
	133
	134	memset(&header, 0, sizeof(header));
f1696ee3	135	strbuf_init(&ext_header, 0);
3d74982f RS	136
	137	if (!sha1) {
	138	*header.typeflag = TYPEFLAG_GLOBAL_HEADER;
	139	mode = 0100666;
	140	strcpy(header.name, "pax_global_header");
	141	} else if (!path) {
	142	*header.typeflag = TYPEFLAG_EXT_HEADER;
	143	mode = 0100666;
	144	sprintf(header.name, "%s.paxheader", sha1_to_hex(sha1));
	145	} else {
	146	if (verbose)
b449f4cf	147	fprintf(stderr, "%.*s\n", (int)path->len, path->buf);
302b9282	148	if (S_ISDIR(mode) \|\| S_ISGITLINK(mode)) {
3d74982f RS	149	*header.typeflag = TYPEFLAG_DIR;
	150	mode = (mode \| 0777) & ~tar_umask;
	151	} else if (S_ISLNK(mode)) {
	152	*header.typeflag = TYPEFLAG_LNK;
	153	mode \|= 0777;
	154	} else if (S_ISREG(mode)) {
	155	*header.typeflag = TYPEFLAG_REG;
	156	mode = (mode \| ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
	157	} else {
	158	error("unsupported file mode: 0%o (SHA1: %s)",
	159	mode, sha1_to_hex(sha1));
	160	return;
	161	}
	162	if (path->len > sizeof(header.name)) {
	163	int plen = get_path_prefix(path, sizeof(header.prefix));
	164	int rest = path->len - plen - 1;
	165	if (plen > 0 && rest <= sizeof(header.name)) {
	166	memcpy(header.prefix, path->buf, plen);
	167	memcpy(header.name, path->buf + plen + 1, rest);
	168	} else {
	169	sprintf(header.name, "%s.data",
	170	sha1_to_hex(sha1));
	171	strbuf_append_ext_header(&ext_header, "path",
	172	path->buf, path->len);
	173	}
	174	} else
	175	memcpy(header.name, path->buf, path->len);
	176	}
	177
	178	if (S_ISLNK(mode) && buffer) {
	179	if (size > sizeof(header.linkname)) {
	180	sprintf(header.linkname, "see %s.paxheader",
	181	sha1_to_hex(sha1));
	182	strbuf_append_ext_header(&ext_header, "linkpath",
	183	buffer, size);
	184	} else
	185	memcpy(header.linkname, buffer, size);
	186	}
	187
	188	sprintf(header.mode, "%07o", mode & 07777);
	189	sprintf(header.size, "%011lo", S_ISREG(mode) ? size : 0);
	190	sprintf(header.mtime, "%011lo", archive_time);
	191
3d74982f RS	192	sprintf(header.uid, "%07o", 0);
3d74982f RS	193	sprintf(header.gid, "%07o", 0);
f08b3b0e RS	194	strlcpy(header.uname, "root", sizeof(header.uname));
f08b3b0e RS	195	strlcpy(header.gname, "root", sizeof(header.gname));
3d74982f RS	196	sprintf(header.devmajor, "%07o", 0);
	197	sprintf(header.devminor, "%07o", 0);
	198
	199	memcpy(header.magic, "ustar", 6);
	200	memcpy(header.version, "00", 2);
	201
	202	sprintf(header.chksum, "%07o", ustar_header_chksum(&header));
	203
	204	if (ext_header.len > 0) {
	205	write_entry(sha1, NULL, 0, ext_header.buf, ext_header.len);
3d74982f	206	}
7a604f16	207	strbuf_release(&ext_header);
3d74982f RS	208	write_blocked(&header, sizeof(header));
	209	if (S_ISREG(mode) && buffer && size > 0)
	210	write_blocked(buffer, size);
	211	}
	212
	213	static void write_global_extended_header(const unsigned char *sha1)
	214	{
	215	struct strbuf ext_header;
7a604f16	216
f1696ee3	217	strbuf_init(&ext_header, 0);
3d74982f RS	218	strbuf_append_ext_header(&ext_header, "comment", sha1_to_hex(sha1), 40);
3d74982f RS	219	write_entry(NULL, NULL, 0, ext_header.buf, ext_header.len);
7a604f16	220	strbuf_release(&ext_header);
3d74982f RS	221	}
	222
	223	static int git_tar_config(const char var, const char value)
	224	{
	225	if (!strcmp(var, "tar.umask")) {
cc1816b0	226	if (value && !strcmp(value, "user")) {
3d74982f RS	227	tar_umask = umask(0);
	228	umask(tar_umask);
	229	} else {
	230	tar_umask = git_config_int(var, value);
	231	}
	232	return 0;
	233	}
	234	return git_default_config(var, value);
	235	}
	236
	237	static int write_tar_entry(const unsigned char *sha1,
	238	const char *base, int baselen,
	239	const char *filename, unsigned mode, int stage)
	240	{
7a604f16	241	static struct strbuf path = STRBUF_INIT;
3d74982f	242	void *buffer;
21666f1a	243	enum object_type type;
3d74982f RS	244	unsigned long size;
3d74982f RS	245
7a604f16	246	strbuf_reset(&path);
e03e05ff	247	strbuf_grow(&path, PATH_MAX);
7a604f16	248	strbuf_add(&path, base, baselen);
e03e05ff	249	strbuf_addstr(&path, filename);
302b9282	250	if (S_ISDIR(mode) \|\| S_ISGITLINK(mode)) {
7a604f16	251	strbuf_addch(&path, '/');
3d74982f RS	252	buffer = NULL;
	253	size = 0;
	254	} else {
ac7fa277 RS	255	buffer = sha1_file_to_archive(path.buf + base_len, sha1, mode,
ac7fa277 RS	256	&type, &size, commit);
3d74982f RS	257	if (!buffer)
	258	die("cannot read %s", sha1_to_hex(sha1));
	259	}
	260
	261	write_entry(sha1, &path, mode, buffer, size);
	262	free(buffer);
	263
	264	return READ_TREE_RECURSIVE;
	265	}
	266
	267	int write_tar_archive(struct archiver_args *args)
	268	{
	269	int plen = args->base ? strlen(args->base) : 0;
	270
	271	git_config(git_tar_config);
	272
	273	archive_time = args->time;
	274	verbose = args->verbose;
8460b2fc	275	commit = args->commit;
ac7fa277	276	base_len = args->base ? strlen(args->base) : 0;
3d74982f RS	277
	278	if (args->commit_sha1)
	279	write_global_extended_header(args->commit_sha1);
	280
	281	if (args->base && plen > 0 && args->base[plen - 1] == '/') {
	282	char *base = xstrdup(args->base);
	283	int baselen = strlen(base);
	284
	285	while (baselen > 0 && base[baselen - 1] == '/')
	286	base[--baselen] = '\0';
	287	write_tar_entry(args->tree->object.sha1, "", 0, base, 040777, 0);
	288	free(base);
	289	}
	290	read_tree_recursive(args->tree, args->base, plen, 0,
	291	args->pathspec, write_tar_entry);
	292	write_trailer();
	293
	294	return 0;
	295	}