list-objects: drop name_path entirely
[git/git-svn.git] / wrapper.c
blob29a45d2654e982dbbb3fc328e16c01713d8a7fb5
1 /*
2 * Various trivial helper wrappers around standard functions
3 */
4 #include "cache.h"
6 static void do_nothing(size_t size)
10 static void (*try_to_free_routine)(size_t size) = do_nothing;
12 static int memory_limit_check(size_t size, int gentle)
14 static size_t limit = 0;
15 if (!limit) {
16 limit = git_env_ulong("GIT_ALLOC_LIMIT", 0);
17 if (!limit)
18 limit = SIZE_MAX;
20 if (size > limit) {
21 if (gentle) {
22 error("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX,
23 (uintmax_t)size, (uintmax_t)limit);
24 return -1;
25 } else
26 die("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX,
27 (uintmax_t)size, (uintmax_t)limit);
29 return 0;
32 try_to_free_t set_try_to_free_routine(try_to_free_t routine)
34 try_to_free_t old = try_to_free_routine;
35 if (!routine)
36 routine = do_nothing;
37 try_to_free_routine = routine;
38 return old;
41 char *xstrdup(const char *str)
43 char *ret = strdup(str);
44 if (!ret) {
45 try_to_free_routine(strlen(str) + 1);
46 ret = strdup(str);
47 if (!ret)
48 die("Out of memory, strdup failed");
50 return ret;
53 static void *do_xmalloc(size_t size, int gentle)
55 void *ret;
57 if (memory_limit_check(size, gentle))
58 return NULL;
59 ret = malloc(size);
60 if (!ret && !size)
61 ret = malloc(1);
62 if (!ret) {
63 try_to_free_routine(size);
64 ret = malloc(size);
65 if (!ret && !size)
66 ret = malloc(1);
67 if (!ret) {
68 if (!gentle)
69 die("Out of memory, malloc failed (tried to allocate %lu bytes)",
70 (unsigned long)size);
71 else {
72 error("Out of memory, malloc failed (tried to allocate %lu bytes)",
73 (unsigned long)size);
74 return NULL;
78 #ifdef XMALLOC_POISON
79 memset(ret, 0xA5, size);
80 #endif
81 return ret;
84 void *xmalloc(size_t size)
86 return do_xmalloc(size, 0);
89 static void *do_xmallocz(size_t size, int gentle)
91 void *ret;
92 if (unsigned_add_overflows(size, 1)) {
93 if (gentle) {
94 error("Data too large to fit into virtual memory space.");
95 return NULL;
96 } else
97 die("Data too large to fit into virtual memory space.");
99 ret = do_xmalloc(size + 1, gentle);
100 if (ret)
101 ((char*)ret)[size] = 0;
102 return ret;
105 void *xmallocz(size_t size)
107 return do_xmallocz(size, 0);
110 void *xmallocz_gently(size_t size)
112 return do_xmallocz(size, 1);
116 * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
117 * "data" to the allocated memory, zero terminates the allocated memory,
118 * and returns a pointer to the allocated memory. If the allocation fails,
119 * the program dies.
121 void *xmemdupz(const void *data, size_t len)
123 return memcpy(xmallocz(len), data, len);
126 char *xstrndup(const char *str, size_t len)
128 char *p = memchr(str, '\0', len);
129 return xmemdupz(str, p ? p - str : len);
132 void *xrealloc(void *ptr, size_t size)
134 void *ret;
136 memory_limit_check(size, 0);
137 ret = realloc(ptr, size);
138 if (!ret && !size)
139 ret = realloc(ptr, 1);
140 if (!ret) {
141 try_to_free_routine(size);
142 ret = realloc(ptr, size);
143 if (!ret && !size)
144 ret = realloc(ptr, 1);
145 if (!ret)
146 die("Out of memory, realloc failed");
148 return ret;
151 void *xcalloc(size_t nmemb, size_t size)
153 void *ret;
155 memory_limit_check(size * nmemb, 0);
156 ret = calloc(nmemb, size);
157 if (!ret && (!nmemb || !size))
158 ret = calloc(1, 1);
159 if (!ret) {
160 try_to_free_routine(nmemb * size);
161 ret = calloc(nmemb, size);
162 if (!ret && (!nmemb || !size))
163 ret = calloc(1, 1);
164 if (!ret)
165 die("Out of memory, calloc failed");
167 return ret;
171 * Limit size of IO chunks, because huge chunks only cause pain. OS X
172 * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
173 * the absence of bugs, large chunks can result in bad latencies when
174 * you decide to kill the process.
176 * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
177 * that is smaller than that, clip it to SSIZE_MAX, as a call to
178 * read(2) or write(2) larger than that is allowed to fail. As the last
179 * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
180 * to override this, if the definition of SSIZE_MAX given by the platform
181 * is broken.
183 #ifndef MAX_IO_SIZE
184 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
185 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
186 # define MAX_IO_SIZE SSIZE_MAX
187 # else
188 # define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
189 # endif
190 #endif
193 * xopen() is the same as open(), but it die()s if the open() fails.
195 int xopen(const char *path, int oflag, ...)
197 mode_t mode = 0;
198 va_list ap;
201 * va_arg() will have undefined behavior if the specified type is not
202 * compatible with the argument type. Since integers are promoted to
203 * ints, we fetch the next argument as an int, and then cast it to a
204 * mode_t to avoid undefined behavior.
206 va_start(ap, oflag);
207 if (oflag & O_CREAT)
208 mode = va_arg(ap, int);
209 va_end(ap);
211 for (;;) {
212 int fd = open(path, oflag, mode);
213 if (fd >= 0)
214 return fd;
215 if (errno == EINTR)
216 continue;
218 if ((oflag & O_RDWR) == O_RDWR)
219 die_errno(_("could not open '%s' for reading and writing"), path);
220 else if ((oflag & O_WRONLY) == O_WRONLY)
221 die_errno(_("could not open '%s' for writing"), path);
222 else
223 die_errno(_("could not open '%s' for reading"), path);
228 * xread() is the same a read(), but it automatically restarts read()
229 * operations with a recoverable error (EAGAIN and EINTR). xread()
230 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
232 ssize_t xread(int fd, void *buf, size_t len)
234 ssize_t nr;
235 if (len > MAX_IO_SIZE)
236 len = MAX_IO_SIZE;
237 while (1) {
238 nr = read(fd, buf, len);
239 if (nr < 0) {
240 if (errno == EINTR)
241 continue;
242 if (errno == EAGAIN || errno == EWOULDBLOCK) {
243 struct pollfd pfd;
244 pfd.events = POLLIN;
245 pfd.fd = fd;
247 * it is OK if this poll() failed; we
248 * want to leave this infinite loop
249 * only when read() returns with
250 * success, or an expected failure,
251 * which would be checked by the next
252 * call to read(2).
254 poll(&pfd, 1, -1);
257 return nr;
262 * xwrite() is the same a write(), but it automatically restarts write()
263 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
264 * GUARANTEE that "len" bytes is written even if the operation is successful.
266 ssize_t xwrite(int fd, const void *buf, size_t len)
268 ssize_t nr;
269 if (len > MAX_IO_SIZE)
270 len = MAX_IO_SIZE;
271 while (1) {
272 nr = write(fd, buf, len);
273 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
274 continue;
275 return nr;
280 * xpread() is the same as pread(), but it automatically restarts pread()
281 * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES
282 * NOT GUARANTEE that "len" bytes is read even if the data is available.
284 ssize_t xpread(int fd, void *buf, size_t len, off_t offset)
286 ssize_t nr;
287 if (len > MAX_IO_SIZE)
288 len = MAX_IO_SIZE;
289 while (1) {
290 nr = pread(fd, buf, len, offset);
291 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
292 continue;
293 return nr;
297 ssize_t read_in_full(int fd, void *buf, size_t count)
299 char *p = buf;
300 ssize_t total = 0;
302 while (count > 0) {
303 ssize_t loaded = xread(fd, p, count);
304 if (loaded < 0)
305 return -1;
306 if (loaded == 0)
307 return total;
308 count -= loaded;
309 p += loaded;
310 total += loaded;
313 return total;
316 ssize_t write_in_full(int fd, const void *buf, size_t count)
318 const char *p = buf;
319 ssize_t total = 0;
321 while (count > 0) {
322 ssize_t written = xwrite(fd, p, count);
323 if (written < 0)
324 return -1;
325 if (!written) {
326 errno = ENOSPC;
327 return -1;
329 count -= written;
330 p += written;
331 total += written;
334 return total;
337 ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset)
339 char *p = buf;
340 ssize_t total = 0;
342 while (count > 0) {
343 ssize_t loaded = xpread(fd, p, count, offset);
344 if (loaded < 0)
345 return -1;
346 if (loaded == 0)
347 return total;
348 count -= loaded;
349 p += loaded;
350 total += loaded;
351 offset += loaded;
354 return total;
357 int xdup(int fd)
359 int ret = dup(fd);
360 if (ret < 0)
361 die_errno("dup failed");
362 return ret;
366 * xfopen() is the same as fopen(), but it die()s if the fopen() fails.
368 FILE *xfopen(const char *path, const char *mode)
370 for (;;) {
371 FILE *fp = fopen(path, mode);
372 if (fp)
373 return fp;
374 if (errno == EINTR)
375 continue;
377 if (*mode && mode[1] == '+')
378 die_errno(_("could not open '%s' for reading and writing"), path);
379 else if (*mode == 'w' || *mode == 'a')
380 die_errno(_("could not open '%s' for writing"), path);
381 else
382 die_errno(_("could not open '%s' for reading"), path);
386 FILE *xfdopen(int fd, const char *mode)
388 FILE *stream = fdopen(fd, mode);
389 if (stream == NULL)
390 die_errno("Out of memory? fdopen failed");
391 return stream;
394 FILE *fopen_for_writing(const char *path)
396 FILE *ret = fopen(path, "w");
398 if (!ret && errno == EPERM) {
399 if (!unlink(path))
400 ret = fopen(path, "w");
401 else
402 errno = EPERM;
404 return ret;
407 int xmkstemp(char *template)
409 int fd;
410 char origtemplate[PATH_MAX];
411 strlcpy(origtemplate, template, sizeof(origtemplate));
413 fd = mkstemp(template);
414 if (fd < 0) {
415 int saved_errno = errno;
416 const char *nonrelative_template;
418 if (strlen(template) != strlen(origtemplate))
419 template = origtemplate;
421 nonrelative_template = absolute_path(template);
422 errno = saved_errno;
423 die_errno("Unable to create temporary file '%s'",
424 nonrelative_template);
426 return fd;
429 /* git_mkstemp() - create tmp file honoring TMPDIR variable */
430 int git_mkstemp(char *path, size_t len, const char *template)
432 const char *tmp;
433 size_t n;
435 tmp = getenv("TMPDIR");
436 if (!tmp)
437 tmp = "/tmp";
438 n = snprintf(path, len, "%s/%s", tmp, template);
439 if (len <= n) {
440 errno = ENAMETOOLONG;
441 return -1;
443 return mkstemp(path);
446 /* git_mkstemps() - create tmp file with suffix honoring TMPDIR variable. */
447 int git_mkstemps(char *path, size_t len, const char *template, int suffix_len)
449 const char *tmp;
450 size_t n;
452 tmp = getenv("TMPDIR");
453 if (!tmp)
454 tmp = "/tmp";
455 n = snprintf(path, len, "%s/%s", tmp, template);
456 if (len <= n) {
457 errno = ENAMETOOLONG;
458 return -1;
460 return mkstemps(path, suffix_len);
463 /* Adapted from libiberty's mkstemp.c. */
465 #undef TMP_MAX
466 #define TMP_MAX 16384
468 int git_mkstemps_mode(char *pattern, int suffix_len, int mode)
470 static const char letters[] =
471 "abcdefghijklmnopqrstuvwxyz"
472 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
473 "0123456789";
474 static const int num_letters = 62;
475 uint64_t value;
476 struct timeval tv;
477 char *template;
478 size_t len;
479 int fd, count;
481 len = strlen(pattern);
483 if (len < 6 + suffix_len) {
484 errno = EINVAL;
485 return -1;
488 if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) {
489 errno = EINVAL;
490 return -1;
494 * Replace pattern's XXXXXX characters with randomness.
495 * Try TMP_MAX different filenames.
497 gettimeofday(&tv, NULL);
498 value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid();
499 template = &pattern[len - 6 - suffix_len];
500 for (count = 0; count < TMP_MAX; ++count) {
501 uint64_t v = value;
502 /* Fill in the random bits. */
503 template[0] = letters[v % num_letters]; v /= num_letters;
504 template[1] = letters[v % num_letters]; v /= num_letters;
505 template[2] = letters[v % num_letters]; v /= num_letters;
506 template[3] = letters[v % num_letters]; v /= num_letters;
507 template[4] = letters[v % num_letters]; v /= num_letters;
508 template[5] = letters[v % num_letters]; v /= num_letters;
510 fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode);
511 if (fd >= 0)
512 return fd;
514 * Fatal error (EPERM, ENOSPC etc).
515 * It doesn't make sense to loop.
517 if (errno != EEXIST)
518 break;
520 * This is a random value. It is only necessary that
521 * the next TMP_MAX values generated by adding 7777 to
522 * VALUE are different with (module 2^32).
524 value += 7777;
526 /* We return the null string if we can't find a unique file name. */
527 pattern[0] = '\0';
528 return -1;
531 int git_mkstemp_mode(char *pattern, int mode)
533 /* mkstemp is just mkstemps with no suffix */
534 return git_mkstemps_mode(pattern, 0, mode);
537 #ifdef NO_MKSTEMPS
538 int gitmkstemps(char *pattern, int suffix_len)
540 return git_mkstemps_mode(pattern, suffix_len, 0600);
542 #endif
544 int xmkstemp_mode(char *template, int mode)
546 int fd;
547 char origtemplate[PATH_MAX];
548 strlcpy(origtemplate, template, sizeof(origtemplate));
550 fd = git_mkstemp_mode(template, mode);
551 if (fd < 0) {
552 int saved_errno = errno;
553 const char *nonrelative_template;
555 if (!template[0])
556 template = origtemplate;
558 nonrelative_template = absolute_path(template);
559 errno = saved_errno;
560 die_errno("Unable to create temporary file '%s'",
561 nonrelative_template);
563 return fd;
566 static int warn_if_unremovable(const char *op, const char *file, int rc)
568 int err;
569 if (!rc || errno == ENOENT)
570 return 0;
571 err = errno;
572 warning("unable to %s %s: %s", op, file, strerror(errno));
573 errno = err;
574 return rc;
577 int unlink_or_msg(const char *file, struct strbuf *err)
579 int rc = unlink(file);
581 assert(err);
583 if (!rc || errno == ENOENT)
584 return 0;
586 strbuf_addf(err, "unable to unlink %s: %s",
587 file, strerror(errno));
588 return -1;
591 int unlink_or_warn(const char *file)
593 return warn_if_unremovable("unlink", file, unlink(file));
596 int rmdir_or_warn(const char *file)
598 return warn_if_unremovable("rmdir", file, rmdir(file));
601 int remove_or_warn(unsigned int mode, const char *file)
603 return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
606 void warn_on_inaccessible(const char *path)
608 warning(_("unable to access '%s': %s"), path, strerror(errno));
611 static int access_error_is_ok(int err, unsigned flag)
613 return err == ENOENT || err == ENOTDIR ||
614 ((flag & ACCESS_EACCES_OK) && err == EACCES);
617 int access_or_warn(const char *path, int mode, unsigned flag)
619 int ret = access(path, mode);
620 if (ret && !access_error_is_ok(errno, flag))
621 warn_on_inaccessible(path);
622 return ret;
625 int access_or_die(const char *path, int mode, unsigned flag)
627 int ret = access(path, mode);
628 if (ret && !access_error_is_ok(errno, flag))
629 die_errno(_("unable to access '%s'"), path);
630 return ret;
633 char *xgetcwd(void)
635 struct strbuf sb = STRBUF_INIT;
636 if (strbuf_getcwd(&sb))
637 die_errno(_("unable to get current working directory"));
638 return strbuf_detach(&sb, NULL);
641 int xsnprintf(char *dst, size_t max, const char *fmt, ...)
643 va_list ap;
644 int len;
646 va_start(ap, fmt);
647 len = vsnprintf(dst, max, fmt, ap);
648 va_end(ap);
650 if (len < 0)
651 die("BUG: your snprintf is broken");
652 if (len >= max)
653 die("BUG: attempt to snprintf into too-small buffer");
654 return len;
657 static int write_file_v(const char *path, int fatal,
658 const char *fmt, va_list params)
660 struct strbuf sb = STRBUF_INIT;
661 int fd = open(path, O_RDWR | O_CREAT | O_TRUNC, 0666);
662 if (fd < 0) {
663 if (fatal)
664 die_errno(_("could not open %s for writing"), path);
665 return -1;
667 strbuf_vaddf(&sb, fmt, params);
668 strbuf_complete_line(&sb);
669 if (write_in_full(fd, sb.buf, sb.len) != sb.len) {
670 int err = errno;
671 close(fd);
672 strbuf_release(&sb);
673 errno = err;
674 if (fatal)
675 die_errno(_("could not write to %s"), path);
676 return -1;
678 strbuf_release(&sb);
679 if (close(fd)) {
680 if (fatal)
681 die_errno(_("could not close %s"), path);
682 return -1;
684 return 0;
687 int write_file(const char *path, const char *fmt, ...)
689 int status;
690 va_list params;
692 va_start(params, fmt);
693 status = write_file_v(path, 1, fmt, params);
694 va_end(params);
695 return status;
698 int write_file_gently(const char *path, const char *fmt, ...)
700 int status;
701 va_list params;
703 va_start(params, fmt);
704 status = write_file_v(path, 0, fmt, params);
705 va_end(params);
706 return status;
709 void sleep_millisec(int millisec)
711 poll(NULL, 0, millisec);