[thirdparty/git.git] / wrapper.c

/*
 * Various trivial helper wrappers around standard functions
 */
#include "cache.h"

static void try_to_free_builtin(size_t size)
{
	release_pack_memory(size, -1);
}

static void (*try_to_free_routine)(size_t size) = try_to_free_builtin;

try_to_free_t set_try_to_free_routine(try_to_free_t routine)
{
	try_to_free_t old = try_to_free_routine;
	try_to_free_routine = routine;
	return old;
}

char *xstrdup(const char *str)
{
	char *ret = strdup(str);
	if (!ret) {
		try_to_free_routine(strlen(str) + 1);
		ret = strdup(str);
		if (!ret)
			die("Out of memory, strdup failed");
	}
	return ret;
}

void *xmalloc(size_t size)
{
	void *ret = malloc(size);
	if (!ret && !size)
		ret = malloc(1);
	if (!ret) {
		try_to_free_routine(size);
		ret = malloc(size);
		if (!ret && !size)
			ret = malloc(1);
		if (!ret)
			die("Out of memory, malloc failed (tried to allocate %lu bytes)",
			    (unsigned long)size);
	}
#ifdef XMALLOC_POISON
	memset(ret, 0xA5, size);
#endif
	return ret;
}

void *xmallocz(size_t size)
{
	void *ret;
	if (size + 1 < size)
		die("Data too large to fit into virtual memory space.");
	ret = xmalloc(size + 1);
	((char*)ret)[size] = 0;
	return ret;
}

/*
 * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
 * "data" to the allocated memory, zero terminates the allocated memory,
 * and returns a pointer to the allocated memory. If the allocation fails,
 * the program dies.
 */
void *xmemdupz(const void *data, size_t len)
{
	return memcpy(xmallocz(len), data, len);
}

char *xstrndup(const char *str, size_t len)
{
	char *p = memchr(str, '\0', len);
	return xmemdupz(str, p ? p - str : len);
}

void *xrealloc(void *ptr, size_t size)
{
	void *ret = realloc(ptr, size);
	if (!ret && !size)
		ret = realloc(ptr, 1);
	if (!ret) {
		try_to_free_routine(size);
		ret = realloc(ptr, size);
		if (!ret && !size)
			ret = realloc(ptr, 1);
		if (!ret)
			die("Out of memory, realloc failed");
	}
	return ret;
}

void *xcalloc(size_t nmemb, size_t size)
{
	void *ret = calloc(nmemb, size);
	if (!ret && (!nmemb || !size))
		ret = calloc(1, 1);
	if (!ret) {
		try_to_free_routine(nmemb * size);
		ret = calloc(nmemb, size);
		if (!ret && (!nmemb || !size))
			ret = calloc(1, 1);
		if (!ret)
			die("Out of memory, calloc failed");
	}
	return ret;
}

void *xmmap(void *start, size_t length,
	int prot, int flags, int fd, off_t offset)
{
	void *ret = mmap(start, length, prot, flags, fd, offset);
	if (ret == MAP_FAILED) {
		if (!length)
			return NULL;
		release_pack_memory(length, fd);
		ret = mmap(start, length, prot, flags, fd, offset);
		if (ret == MAP_FAILED)
			die_errno("Out of memory? mmap failed");
	}
	return ret;
}

/*
 * xread() is the same a read(), but it automatically restarts read()
 * operations with a recoverable error (EAGAIN and EINTR). xread()
 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
 */
ssize_t xread(int fd, void *buf, size_t len)
{
	ssize_t nr;
	while (1) {
		nr = read(fd, buf, len);
		if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
			continue;
		return nr;
	}
}

/*
 * xwrite() is the same a write(), but it automatically restarts write()
 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
 * GUARANTEE that "len" bytes is written even if the operation is successful.
 */
ssize_t xwrite(int fd, const void *buf, size_t len)
{
	ssize_t nr;
	while (1) {
		nr = write(fd, buf, len);
		if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
			continue;
		return nr;
	}
}

ssize_t read_in_full(int fd, void *buf, size_t count)
{
	char *p = buf;
	ssize_t total = 0;

	while (count > 0) {
		ssize_t loaded = xread(fd, p, count);
		if (loaded <= 0)
			return total ? total : loaded;
		count -= loaded;
		p += loaded;
		total += loaded;
	}

	return total;
}

ssize_t write_in_full(int fd, const void *buf, size_t count)
{
	const char *p = buf;
	ssize_t total = 0;

	while (count > 0) {
		ssize_t written = xwrite(fd, p, count);
		if (written < 0)
			return -1;
		if (!written) {
			errno = ENOSPC;
			return -1;
		}
		count -= written;
		p += written;
		total += written;
	}

	return total;
}

int xdup(int fd)
{
	int ret = dup(fd);
	if (ret < 0)
		die_errno("dup failed");
	return ret;
}

FILE *xfdopen(int fd, const char *mode)
{
	FILE *stream = fdopen(fd, mode);
	if (stream == NULL)
		die_errno("Out of memory? fdopen failed");
	return stream;
}

int xmkstemp(char *template)
{
	int fd;

	fd = mkstemp(template);
	if (fd < 0)
		die_errno("Unable to create temporary file");
	return fd;
}

int xmkstemp_mode(char *template, int mode)
{
	int fd;

	fd = git_mkstemp_mode(template, mode);
	if (fd < 0)
		die_errno("Unable to create temporary file");
	return fd;
}

/*
 * zlib wrappers to make sure we don't silently miss errors
 * at init time.
 */
void git_inflate_init(z_streamp strm)
{
	const char *err;

	switch (inflateInit(strm)) {
	case Z_OK:
		return;

	case Z_MEM_ERROR:
		err = "out of memory";
		break;
	case Z_VERSION_ERROR:
		err = "wrong version";
		break;
	default:
		err = "error";
	}
	die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message");
}

void git_inflate_end(z_streamp strm)
{
	if (inflateEnd(strm) != Z_OK)
		error("inflateEnd: %s", strm->msg ? strm->msg : "failed");
}

int git_inflate(z_streamp strm, int flush)
{
	int ret = inflate(strm, flush);
	const char *err;

	switch (ret) {
	/* Out of memory is fatal. */
	case Z_MEM_ERROR:
		die("inflate: out of memory");

	/* Data corruption errors: we may want to recover from them (fsck) */
	case Z_NEED_DICT:
		err = "needs dictionary"; break;
	case Z_DATA_ERROR:
		err = "data stream error"; break;
	case Z_STREAM_ERROR:
		err = "stream consistency error"; break;
	default:
		err = "unknown error"; break;

	/* Z_BUF_ERROR: normal, needs more space in the output buffer */
	case Z_BUF_ERROR:
	case Z_OK:
	case Z_STREAM_END:
		return ret;
	}
	error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message");
	return ret;
}

int odb_mkstemp(char *template, size_t limit, const char *pattern)
{
	int fd;
	/*
	 * we let the umask do its job, don't try to be more
	 * restrictive except to remove write permission.
	 */
	int mode = 0444;
	snprintf(template, limit, "%s/%s",
		 get_object_directory(), pattern);
	fd = git_mkstemp_mode(template, mode);
	if (0 <= fd)
		return fd;

	/* slow path */
	/* some mkstemp implementations erase template on failure */
	snprintf(template, limit, "%s/%s",
		 get_object_directory(), pattern);
	safe_create_leading_directories(template);
	return xmkstemp_mode(template, mode);
}

int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1)
{
	int fd;

	snprintf(name, namesz, "%s/pack/pack-%s.keep",
		 get_object_directory(), sha1_to_hex(sha1));
	fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
	if (0 <= fd)
		return fd;

	/* slow path */
	safe_create_leading_directories(name);
	return open(name, O_RDWR|O_CREAT|O_EXCL, 0600);
}

static int warn_if_unremovable(const char *op, const char *file, int rc)
{
	if (rc < 0) {
		int err = errno;
		if (ENOENT != err) {
			warning("unable to %s %s: %s",
				op, file, strerror(errno));
			errno = err;
		}
	}
	return rc;
}

int unlink_or_warn(const char *file)
{
	return warn_if_unremovable("unlink", file, unlink(file));
}

int rmdir_or_warn(const char *file)
{
	return warn_if_unremovable("rmdir", file, rmdir(file));
}

int remove_or_warn(unsigned int mode, const char *file)
{
	return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
}
Commit	Line	Data
112db553 LT	1	/*
	2	* Various trivial helper wrappers around standard functions
	3	*/
	4	#include "cache.h"
	5
a9a74636 NP	6	static void try_to_free_builtin(size_t size)
	7	{
	8	release_pack_memory(size, -1);
	9	}
	10
	11	static void (*try_to_free_routine)(size_t size) = try_to_free_builtin;
	12
851c34b0	13	try_to_free_t set_try_to_free_routine(try_to_free_t routine)
a9a74636	14	{
851c34b0 JS	15	try_to_free_t old = try_to_free_routine;
	16	try_to_free_routine = routine;
	17	return old;
a9a74636 NP	18	}
a9a74636 NP	19
112db553 LT	20	char xstrdup(const char str)
	21	{
	22	char *ret = strdup(str);
	23	if (!ret) {
a9a74636	24	try_to_free_routine(strlen(str) + 1);
112db553 LT	25	ret = strdup(str);
	26	if (!ret)
	27	die("Out of memory, strdup failed");
	28	}
	29	return ret;
	30	}
	31
	32	void *xmalloc(size_t size)
	33	{
	34	void *ret = malloc(size);
	35	if (!ret && !size)
	36	ret = malloc(1);
	37	if (!ret) {
a9a74636	38	try_to_free_routine(size);
112db553 LT	39	ret = malloc(size);
	40	if (!ret && !size)
	41	ret = malloc(1);
	42	if (!ret)
8bd9fd50 MM	43	die("Out of memory, malloc failed (tried to allocate %lu bytes)",
8bd9fd50 MM	44	(unsigned long)size);
112db553 LT	45	}
	46	#ifdef XMALLOC_POISON
	47	memset(ret, 0xA5, size);
	48	#endif
	49	return ret;
	50	}
	51
5bf9219d IL	52	void *xmallocz(size_t size)
	53	{
	54	void *ret;
	55	if (size + 1 < size)
	56	die("Data too large to fit into virtual memory space.");
	57	ret = xmalloc(size + 1);
	58	((char*)ret)[size] = 0;
	59	return ret;
	60	}
	61
112db553 LT	62	/*
	63	* xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
	64	* "data" to the allocated memory, zero terminates the allocated memory,
	65	* and returns a pointer to the allocated memory. If the allocation fails,
	66	* the program dies.
	67	*/
	68	void xmemdupz(const void data, size_t len)
	69	{
5bf9219d	70	return memcpy(xmallocz(len), data, len);
112db553 LT	71	}
	72
	73	char xstrndup(const char str, size_t len)
	74	{
	75	char *p = memchr(str, '\0', len);
	76	return xmemdupz(str, p ? p - str : len);
	77	}
	78
	79	void xrealloc(void ptr, size_t size)
	80	{
	81	void *ret = realloc(ptr, size);
	82	if (!ret && !size)
	83	ret = realloc(ptr, 1);
	84	if (!ret) {
a9a74636	85	try_to_free_routine(size);
112db553 LT	86	ret = realloc(ptr, size);
	87	if (!ret && !size)
	88	ret = realloc(ptr, 1);
	89	if (!ret)
	90	die("Out of memory, realloc failed");
	91	}
	92	return ret;
	93	}
	94
	95	void *xcalloc(size_t nmemb, size_t size)
	96	{
	97	void *ret = calloc(nmemb, size);
	98	if (!ret && (!nmemb \|\| !size))
	99	ret = calloc(1, 1);
	100	if (!ret) {
a9a74636	101	try_to_free_routine(nmemb * size);
112db553 LT	102	ret = calloc(nmemb, size);
	103	if (!ret && (!nmemb \|\| !size))
	104	ret = calloc(1, 1);
	105	if (!ret)
	106	die("Out of memory, calloc failed");
	107	}
	108	return ret;
	109	}
	110
	111	void xmmap(void start, size_t length,
	112	int prot, int flags, int fd, off_t offset)
	113	{
	114	void *ret = mmap(start, length, prot, flags, fd, offset);
	115	if (ret == MAP_FAILED) {
	116	if (!length)
	117	return NULL;
	118	release_pack_memory(length, fd);
	119	ret = mmap(start, length, prot, flags, fd, offset);
	120	if (ret == MAP_FAILED)
d824cbba	121	die_errno("Out of memory? mmap failed");
112db553 LT	122	}
	123	return ret;
	124	}
	125
	126	/*
	127	* xread() is the same a read(), but it automatically restarts read()
	128	* operations with a recoverable error (EAGAIN and EINTR). xread()
	129	* DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
	130	*/
	131	ssize_t xread(int fd, void *buf, size_t len)
	132	{
	133	ssize_t nr;
	134	while (1) {
	135	nr = read(fd, buf, len);
	136	if ((nr < 0) && (errno == EAGAIN \|\| errno == EINTR))
	137	continue;
	138	return nr;
	139	}
	140	}
	141
	142	/*
	143	* xwrite() is the same a write(), but it automatically restarts write()
	144	* operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
	145	* GUARANTEE that "len" bytes is written even if the operation is successful.
	146	*/
	147	ssize_t xwrite(int fd, const void *buf, size_t len)
	148	{
	149	ssize_t nr;
	150	while (1) {
	151	nr = write(fd, buf, len);
	152	if ((nr < 0) && (errno == EAGAIN \|\| errno == EINTR))
	153	continue;
	154	return nr;
	155	}
	156	}
	157
559e840b JH	158	ssize_t read_in_full(int fd, void *buf, size_t count)
	159	{
	160	char *p = buf;
	161	ssize_t total = 0;
	162
	163	while (count > 0) {
	164	ssize_t loaded = xread(fd, p, count);
	165	if (loaded <= 0)
	166	return total ? total : loaded;
	167	count -= loaded;
	168	p += loaded;
	169	total += loaded;
	170	}
	171
	172	return total;
	173	}
	174
	175	ssize_t write_in_full(int fd, const void *buf, size_t count)
	176	{
	177	const char *p = buf;
	178	ssize_t total = 0;
	179
	180	while (count > 0) {
	181	ssize_t written = xwrite(fd, p, count);
	182	if (written < 0)
	183	return -1;
	184	if (!written) {
	185	errno = ENOSPC;
	186	return -1;
	187	}
	188	count -= written;
	189	p += written;
	190	total += written;
	191	}
	192
	193	return total;
	194	}
	195
112db553 LT	196	int xdup(int fd)
	197	{
	198	int ret = dup(fd);
	199	if (ret < 0)
d824cbba	200	die_errno("dup failed");
112db553 LT	201	return ret;
	202	}
	203
	204	FILE xfdopen(int fd, const char mode)
	205	{
	206	FILE *stream = fdopen(fd, mode);
	207	if (stream == NULL)
d824cbba	208	die_errno("Out of memory? fdopen failed");
112db553 LT	209	return stream;
	210	}
	211
	212	int xmkstemp(char *template)
	213	{
	214	int fd;
	215
	216	fd = mkstemp(template);
	217	if (fd < 0)
d824cbba	218	die_errno("Unable to create temporary file");
112db553 LT	219	return fd;
112db553 LT	220	}
39c68542	221
b862b61c MM	222	int xmkstemp_mode(char *template, int mode)
	223	{
	224	int fd;
	225
	226	fd = git_mkstemp_mode(template, mode);
	227	if (fd < 0)
	228	die_errno("Unable to create temporary file");
	229	return fd;
	230	}
	231
39c68542 LT	232	/*
	233	* zlib wrappers to make sure we don't silently miss errors
	234	* at init time.
	235	*/
	236	void git_inflate_init(z_streamp strm)
	237	{
	238	const char *err;
	239
	240	switch (inflateInit(strm)) {
	241	case Z_OK:
	242	return;
	243
	244	case Z_MEM_ERROR:
	245	err = "out of memory";
	246	break;
	247	case Z_VERSION_ERROR:
	248	err = "wrong version";
	249	break;
	250	default:
	251	err = "error";
	252	}
	253	die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message");
	254	}
	255
	256	void git_inflate_end(z_streamp strm)
	257	{
	258	if (inflateEnd(strm) != Z_OK)
	259	error("inflateEnd: %s", strm->msg ? strm->msg : "failed");
	260	}
	261
	262	int git_inflate(z_streamp strm, int flush)
	263	{
	264	int ret = inflate(strm, flush);
	265	const char *err;
	266
	267	switch (ret) {
	268	/* Out of memory is fatal. */
	269	case Z_MEM_ERROR:
	270	die("inflate: out of memory");
	271
	272	/* Data corruption errors: we may want to recover from them (fsck) */
	273	case Z_NEED_DICT:
	274	err = "needs dictionary"; break;
	275	case Z_DATA_ERROR:
	276	err = "data stream error"; break;
	277	case Z_STREAM_ERROR:
	278	err = "stream consistency error"; break;
	279	default:
	280	err = "unknown error"; break;
	281
	282	/* Z_BUF_ERROR: normal, needs more space in the output buffer */
	283	case Z_BUF_ERROR:
	284	case Z_OK:
	285	case Z_STREAM_END:
	286	return ret;
	287	}
	288	error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message");
	289	return ret;
	290	}
bb0cebd7	291
6e180cdc JH	292	int odb_mkstemp(char template, size_t limit, const char pattern)
	293	{
	294	int fd;
f80c7ae8 MM	295	/*
	296	* we let the umask do its job, don't try to be more
	297	* restrictive except to remove write permission.
	298	*/
	299	int mode = 0444;
6e180cdc JH	300	snprintf(template, limit, "%s/%s",
6e180cdc JH	301	get_object_directory(), pattern);
f80c7ae8	302	fd = git_mkstemp_mode(template, mode);
6e180cdc JH	303	if (0 <= fd)
	304	return fd;
	305
	306	/* slow path */
2c626e5f	307	/* some mkstemp implementations erase template on failure */
6e180cdc JH	308	snprintf(template, limit, "%s/%s",
6e180cdc JH	309	get_object_directory(), pattern);
2c626e5f	310	safe_create_leading_directories(template);
f80c7ae8	311	return xmkstemp_mode(template, mode);
6e180cdc JH	312	}
	313
	314	int odb_pack_keep(char name, size_t namesz, unsigned char sha1)
	315	{
	316	int fd;
	317
	318	snprintf(name, namesz, "%s/pack/pack-%s.keep",
	319	get_object_directory(), sha1_to_hex(sha1));
	320	fd = open(name, O_RDWR\|O_CREAT\|O_EXCL, 0600);
	321	if (0 <= fd)
	322	return fd;
	323
	324	/* slow path */
	325	safe_create_leading_directories(name);
	326	return open(name, O_RDWR\|O_CREAT\|O_EXCL, 0600);
	327	}
fc71db39	328
10e13ec8	329	static int warn_if_unremovable(const char op, const char file, int rc)
fc71db39	330	{
fc71db39 AR	331	if (rc < 0) {
	332	int err = errno;
	333	if (ENOENT != err) {
10e13ec8 PC	334	warning("unable to %s %s: %s",
10e13ec8 PC	335	op, file, strerror(errno));
fc71db39 AR	336	errno = err;
	337	}
	338	}
	339	return rc;
	340	}
	341
10e13ec8 PC	342	int unlink_or_warn(const char *file)
	343	{
	344	return warn_if_unremovable("unlink", file, unlink(file));
	345	}
d1723296 PC	346
	347	int rmdir_or_warn(const char *file)
	348	{
	349	return warn_if_unremovable("rmdir", file, rmdir(file));
	350	}
80d706af PC	351
	352	int remove_or_warn(unsigned int mode, const char *file)
	353	{
	354	return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
	355	}