vcs-svn: use error_errno()
[git/git.git] / wrapper.c
CommitLineData
112db553
LT
1/*
2 * Various trivial helper wrappers around standard functions
3 */
4#include "cache.h"
5
e0500293 6static void do_nothing(size_t size)
a9a74636 7{
a9a74636
NP
8}
9
e0500293 10static void (*try_to_free_routine)(size_t size) = do_nothing;
a9a74636 11
f8bb1d94 12static int memory_limit_check(size_t size, int gentle)
d41489a6 13{
9927d962
SP
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;
d41489a6 19 }
f0d89001 20 if (size > limit) {
f8bb1d94 21 if (gentle) {
f0d89001
JH
22 error("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX,
23 (uintmax_t)size, (uintmax_t)limit);
f8bb1d94
NTND
24 return -1;
25 } else
f0d89001
JH
26 die("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX,
27 (uintmax_t)size, (uintmax_t)limit);
f8bb1d94
NTND
28 }
29 return 0;
d41489a6
NTND
30}
31
851c34b0 32try_to_free_t set_try_to_free_routine(try_to_free_t routine)
a9a74636 33{
851c34b0 34 try_to_free_t old = try_to_free_routine;
00b0d7f7
JH
35 if (!routine)
36 routine = do_nothing;
851c34b0
JS
37 try_to_free_routine = routine;
38 return old;
a9a74636
NP
39}
40
112db553
LT
41char *xstrdup(const char *str)
42{
43 char *ret = strdup(str);
44 if (!ret) {
a9a74636 45 try_to_free_routine(strlen(str) + 1);
112db553
LT
46 ret = strdup(str);
47 if (!ret)
48 die("Out of memory, strdup failed");
49 }
50 return ret;
51}
52
f8bb1d94 53static void *do_xmalloc(size_t size, int gentle)
112db553 54{
d41489a6
NTND
55 void *ret;
56
f8bb1d94
NTND
57 if (memory_limit_check(size, gentle))
58 return NULL;
d41489a6 59 ret = malloc(size);
112db553
LT
60 if (!ret && !size)
61 ret = malloc(1);
62 if (!ret) {
a9a74636 63 try_to_free_routine(size);
112db553
LT
64 ret = malloc(size);
65 if (!ret && !size)
66 ret = malloc(1);
f8bb1d94
NTND
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;
75 }
76 }
112db553
LT
77 }
78#ifdef XMALLOC_POISON
79 memset(ret, 0xA5, size);
80#endif
81 return ret;
82}
83
f8bb1d94
NTND
84void *xmalloc(size_t size)
85{
86 return do_xmalloc(size, 0);
87}
88
89static void *do_xmallocz(size_t size, int gentle)
5bf9219d
IL
90{
91 void *ret;
f8bb1d94
NTND
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.");
98 }
99 ret = do_xmalloc(size + 1, gentle);
100 if (ret)
101 ((char*)ret)[size] = 0;
5bf9219d
IL
102 return ret;
103}
104
f8bb1d94
NTND
105void *xmallocz(size_t size)
106{
107 return do_xmallocz(size, 0);
108}
109
110void *xmallocz_gently(size_t size)
111{
112 return do_xmallocz(size, 1);
113}
114
112db553
LT
115/*
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.
120 */
121void *xmemdupz(const void *data, size_t len)
122{
5bf9219d 123 return memcpy(xmallocz(len), data, len);
112db553
LT
124}
125
126char *xstrndup(const char *str, size_t len)
127{
128 char *p = memchr(str, '\0', len);
129 return xmemdupz(str, p ? p - str : len);
130}
131
132void *xrealloc(void *ptr, size_t size)
133{
d41489a6
NTND
134 void *ret;
135
f8bb1d94 136 memory_limit_check(size, 0);
d41489a6 137 ret = realloc(ptr, size);
112db553
LT
138 if (!ret && !size)
139 ret = realloc(ptr, 1);
140 if (!ret) {
a9a74636 141 try_to_free_routine(size);
112db553
LT
142 ret = realloc(ptr, size);
143 if (!ret && !size)
144 ret = realloc(ptr, 1);
145 if (!ret)
146 die("Out of memory, realloc failed");
147 }
148 return ret;
149}
150
151void *xcalloc(size_t nmemb, size_t size)
152{
d41489a6
NTND
153 void *ret;
154
e7792a74
JK
155 if (unsigned_mult_overflows(nmemb, size))
156 die("data too large to fit into virtual memory space");
157
f8bb1d94 158 memory_limit_check(size * nmemb, 0);
d41489a6 159 ret = calloc(nmemb, size);
112db553
LT
160 if (!ret && (!nmemb || !size))
161 ret = calloc(1, 1);
162 if (!ret) {
a9a74636 163 try_to_free_routine(nmemb * size);
112db553
LT
164 ret = calloc(nmemb, size);
165 if (!ret && (!nmemb || !size))
166 ret = calloc(1, 1);
167 if (!ret)
168 die("Out of memory, calloc failed");
169 }
170 return ret;
171}
172
0b6806b9
SP
173/*
174 * Limit size of IO chunks, because huge chunks only cause pain. OS X
175 * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
382d20e3 176 * the absence of bugs, large chunks can result in bad latencies when
0b6806b9 177 * you decide to kill the process.
a983e6ac
JH
178 *
179 * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
180 * that is smaller than that, clip it to SSIZE_MAX, as a call to
181 * read(2) or write(2) larger than that is allowed to fail. As the last
182 * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
183 * to override this, if the definition of SSIZE_MAX given by the platform
184 * is broken.
0b6806b9 185 */
a983e6ac
JH
186#ifndef MAX_IO_SIZE
187# define MAX_IO_SIZE_DEFAULT (8*1024*1024)
188# if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
189# define MAX_IO_SIZE SSIZE_MAX
190# else
191# define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
192# endif
193#endif
0b6806b9 194
3ff53df7
PT
195/**
196 * xopen() is the same as open(), but it die()s if the open() fails.
197 */
198int xopen(const char *path, int oflag, ...)
199{
200 mode_t mode = 0;
201 va_list ap;
202
203 /*
204 * va_arg() will have undefined behavior if the specified type is not
205 * compatible with the argument type. Since integers are promoted to
206 * ints, we fetch the next argument as an int, and then cast it to a
207 * mode_t to avoid undefined behavior.
208 */
209 va_start(ap, oflag);
210 if (oflag & O_CREAT)
211 mode = va_arg(ap, int);
212 va_end(ap);
213
214 for (;;) {
215 int fd = open(path, oflag, mode);
216 if (fd >= 0)
217 return fd;
218 if (errno == EINTR)
219 continue;
220
221 if ((oflag & O_RDWR) == O_RDWR)
222 die_errno(_("could not open '%s' for reading and writing"), path);
223 else if ((oflag & O_WRONLY) == O_WRONLY)
224 die_errno(_("could not open '%s' for writing"), path);
225 else
226 die_errno(_("could not open '%s' for reading"), path);
227 }
228}
229
112db553
LT
230/*
231 * xread() is the same a read(), but it automatically restarts read()
232 * operations with a recoverable error (EAGAIN and EINTR). xread()
233 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
234 */
235ssize_t xread(int fd, void *buf, size_t len)
236{
237 ssize_t nr;
0b6806b9
SP
238 if (len > MAX_IO_SIZE)
239 len = MAX_IO_SIZE;
112db553
LT
240 while (1) {
241 nr = read(fd, buf, len);
1079c4be
SB
242 if (nr < 0) {
243 if (errno == EINTR)
244 continue;
245 if (errno == EAGAIN || errno == EWOULDBLOCK) {
246 struct pollfd pfd;
247 pfd.events = POLLIN;
248 pfd.fd = fd;
249 /*
250 * it is OK if this poll() failed; we
251 * want to leave this infinite loop
252 * only when read() returns with
253 * success, or an expected failure,
254 * which would be checked by the next
255 * call to read(2).
256 */
257 poll(&pfd, 1, -1);
258 }
259 }
112db553
LT
260 return nr;
261 }
262}
263
264/*
265 * xwrite() is the same a write(), but it automatically restarts write()
266 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
267 * GUARANTEE that "len" bytes is written even if the operation is successful.
268 */
269ssize_t xwrite(int fd, const void *buf, size_t len)
270{
271 ssize_t nr;
0b6806b9
SP
272 if (len > MAX_IO_SIZE)
273 len = MAX_IO_SIZE;
112db553
LT
274 while (1) {
275 nr = write(fd, buf, len);
276 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
9aa91af0
YM
277 continue;
278 return nr;
279 }
280}
281
282/*
283 * xpread() is the same as pread(), but it automatically restarts pread()
284 * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES
285 * NOT GUARANTEE that "len" bytes is read even if the data is available.
286 */
287ssize_t xpread(int fd, void *buf, size_t len, off_t offset)
288{
289 ssize_t nr;
290 if (len > MAX_IO_SIZE)
291 len = MAX_IO_SIZE;
292 while (1) {
293 nr = pread(fd, buf, len, offset);
294 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
112db553
LT
295 continue;
296 return nr;
297 }
298}
299
559e840b
JH
300ssize_t read_in_full(int fd, void *buf, size_t count)
301{
302 char *p = buf;
303 ssize_t total = 0;
304
305 while (count > 0) {
306 ssize_t loaded = xread(fd, p, count);
56d7c27a
JK
307 if (loaded < 0)
308 return -1;
309 if (loaded == 0)
310 return total;
559e840b
JH
311 count -= loaded;
312 p += loaded;
313 total += loaded;
314 }
315
316 return total;
317}
318
319ssize_t write_in_full(int fd, const void *buf, size_t count)
320{
321 const char *p = buf;
322 ssize_t total = 0;
323
324 while (count > 0) {
325 ssize_t written = xwrite(fd, p, count);
326 if (written < 0)
327 return -1;
328 if (!written) {
329 errno = ENOSPC;
330 return -1;
331 }
332 count -= written;
333 p += written;
334 total += written;
335 }
336
337 return total;
338}
339
426ddeea
YM
340ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset)
341{
342 char *p = buf;
343 ssize_t total = 0;
344
345 while (count > 0) {
346 ssize_t loaded = xpread(fd, p, count, offset);
347 if (loaded < 0)
348 return -1;
349 if (loaded == 0)
350 return total;
351 count -= loaded;
352 p += loaded;
353 total += loaded;
354 offset += loaded;
355 }
356
357 return total;
358}
359
112db553
LT
360int xdup(int fd)
361{
362 int ret = dup(fd);
363 if (ret < 0)
d824cbba 364 die_errno("dup failed");
112db553
LT
365 return ret;
366}
367
260eec29
PT
368/**
369 * xfopen() is the same as fopen(), but it die()s if the fopen() fails.
370 */
371FILE *xfopen(const char *path, const char *mode)
372{
373 for (;;) {
374 FILE *fp = fopen(path, mode);
375 if (fp)
376 return fp;
377 if (errno == EINTR)
378 continue;
379
380 if (*mode && mode[1] == '+')
381 die_errno(_("could not open '%s' for reading and writing"), path);
382 else if (*mode == 'w' || *mode == 'a')
383 die_errno(_("could not open '%s' for writing"), path);
384 else
385 die_errno(_("could not open '%s' for reading"), path);
386 }
387}
388
112db553
LT
389FILE *xfdopen(int fd, const char *mode)
390{
391 FILE *stream = fdopen(fd, mode);
392 if (stream == NULL)
d824cbba 393 die_errno("Out of memory? fdopen failed");
112db553
LT
394 return stream;
395}
396
79d7582e
JS
397FILE *fopen_for_writing(const char *path)
398{
399 FILE *ret = fopen(path, "w");
400
401 if (!ret && errno == EPERM) {
402 if (!unlink(path))
403 ret = fopen(path, "w");
404 else
405 errno = EPERM;
406 }
407 return ret;
408}
409
112db553
LT
410int xmkstemp(char *template)
411{
412 int fd;
6cf6bb3e
AE
413 char origtemplate[PATH_MAX];
414 strlcpy(origtemplate, template, sizeof(origtemplate));
112db553
LT
415
416 fd = mkstemp(template);
6cf6bb3e
AE
417 if (fd < 0) {
418 int saved_errno = errno;
419 const char *nonrelative_template;
420
f7be59b4 421 if (strlen(template) != strlen(origtemplate))
6cf6bb3e
AE
422 template = origtemplate;
423
e2a57aac 424 nonrelative_template = absolute_path(template);
6cf6bb3e
AE
425 errno = saved_errno;
426 die_errno("Unable to create temporary file '%s'",
427 nonrelative_template);
428 }
112db553
LT
429 return fd;
430}
39c68542 431
33f23936
JN
432/* git_mkstemp() - create tmp file honoring TMPDIR variable */
433int git_mkstemp(char *path, size_t len, const char *template)
434{
435 const char *tmp;
436 size_t n;
437
438 tmp = getenv("TMPDIR");
439 if (!tmp)
440 tmp = "/tmp";
441 n = snprintf(path, len, "%s/%s", tmp, template);
442 if (len <= n) {
443 errno = ENAMETOOLONG;
444 return -1;
445 }
446 return mkstemp(path);
447}
448
449/* git_mkstemps() - create tmp file with suffix honoring TMPDIR variable. */
450int git_mkstemps(char *path, size_t len, const char *template, int suffix_len)
451{
452 const char *tmp;
453 size_t n;
454
455 tmp = getenv("TMPDIR");
456 if (!tmp)
457 tmp = "/tmp";
458 n = snprintf(path, len, "%s/%s", tmp, template);
459 if (len <= n) {
460 errno = ENAMETOOLONG;
461 return -1;
462 }
463 return mkstemps(path, suffix_len);
464}
465
466/* Adapted from libiberty's mkstemp.c. */
467
468#undef TMP_MAX
469#define TMP_MAX 16384
470
471int git_mkstemps_mode(char *pattern, int suffix_len, int mode)
472{
473 static const char letters[] =
474 "abcdefghijklmnopqrstuvwxyz"
475 "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
476 "0123456789";
477 static const int num_letters = 62;
478 uint64_t value;
479 struct timeval tv;
480 char *template;
481 size_t len;
482 int fd, count;
483
484 len = strlen(pattern);
485
486 if (len < 6 + suffix_len) {
487 errno = EINVAL;
488 return -1;
489 }
490
491 if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) {
492 errno = EINVAL;
493 return -1;
494 }
495
496 /*
497 * Replace pattern's XXXXXX characters with randomness.
498 * Try TMP_MAX different filenames.
499 */
500 gettimeofday(&tv, NULL);
501 value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid();
502 template = &pattern[len - 6 - suffix_len];
503 for (count = 0; count < TMP_MAX; ++count) {
504 uint64_t v = value;
505 /* Fill in the random bits. */
506 template[0] = letters[v % num_letters]; v /= num_letters;
507 template[1] = letters[v % num_letters]; v /= num_letters;
508 template[2] = letters[v % num_letters]; v /= num_letters;
509 template[3] = letters[v % num_letters]; v /= num_letters;
510 template[4] = letters[v % num_letters]; v /= num_letters;
511 template[5] = letters[v % num_letters]; v /= num_letters;
512
513 fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode);
a2cb86c1 514 if (fd >= 0)
33f23936
JN
515 return fd;
516 /*
517 * Fatal error (EPERM, ENOSPC etc).
518 * It doesn't make sense to loop.
519 */
520 if (errno != EEXIST)
521 break;
522 /*
523 * This is a random value. It is only necessary that
524 * the next TMP_MAX values generated by adding 7777 to
525 * VALUE are different with (module 2^32).
526 */
527 value += 7777;
528 }
529 /* We return the null string if we can't find a unique file name. */
530 pattern[0] = '\0';
531 return -1;
532}
533
534int git_mkstemp_mode(char *pattern, int mode)
535{
536 /* mkstemp is just mkstemps with no suffix */
537 return git_mkstemps_mode(pattern, 0, mode);
538}
539
ec145c9c 540#ifdef NO_MKSTEMPS
33f23936
JN
541int gitmkstemps(char *pattern, int suffix_len)
542{
543 return git_mkstemps_mode(pattern, suffix_len, 0600);
544}
ec145c9c 545#endif
33f23936 546
b862b61c
MM
547int xmkstemp_mode(char *template, int mode)
548{
549 int fd;
6cf6bb3e
AE
550 char origtemplate[PATH_MAX];
551 strlcpy(origtemplate, template, sizeof(origtemplate));
b862b61c
MM
552
553 fd = git_mkstemp_mode(template, mode);
6cf6bb3e
AE
554 if (fd < 0) {
555 int saved_errno = errno;
556 const char *nonrelative_template;
557
558 if (!template[0])
559 template = origtemplate;
560
e2a57aac 561 nonrelative_template = absolute_path(template);
6cf6bb3e
AE
562 errno = saved_errno;
563 die_errno("Unable to create temporary file '%s'",
564 nonrelative_template);
565 }
b862b61c
MM
566 return fd;
567}
568
10e13ec8 569static int warn_if_unremovable(const char *op, const char *file, int rc)
fc71db39 570{
1054af7d
RS
571 int err;
572 if (!rc || errno == ENOENT)
573 return 0;
574 err = errno;
575 warning("unable to %s %s: %s", op, file, strerror(errno));
576 errno = err;
fc71db39
AR
577 return rc;
578}
579
9ccc0c08
RS
580int unlink_or_msg(const char *file, struct strbuf *err)
581{
582 int rc = unlink(file);
583
584 assert(err);
585
586 if (!rc || errno == ENOENT)
587 return 0;
588
589 strbuf_addf(err, "unable to unlink %s: %s",
590 file, strerror(errno));
591 return -1;
592}
593
10e13ec8
PC
594int unlink_or_warn(const char *file)
595{
596 return warn_if_unremovable("unlink", file, unlink(file));
597}
d1723296
PC
598
599int rmdir_or_warn(const char *file)
600{
601 return warn_if_unremovable("rmdir", file, rmdir(file));
602}
80d706af
PC
603
604int remove_or_warn(unsigned int mode, const char *file)
605{
606 return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file);
607}
2f705875 608
55b38a48
JH
609void warn_on_inaccessible(const char *path)
610{
611 warning(_("unable to access '%s': %s"), path, strerror(errno));
612}
613
4698c8fe
JN
614static int access_error_is_ok(int err, unsigned flag)
615{
616 return err == ENOENT || err == ENOTDIR ||
617 ((flag & ACCESS_EACCES_OK) && err == EACCES);
618}
619
620int access_or_warn(const char *path, int mode, unsigned flag)
ba8bd830
JK
621{
622 int ret = access(path, mode);
4698c8fe 623 if (ret && !access_error_is_ok(errno, flag))
55b38a48 624 warn_on_inaccessible(path);
ba8bd830
JK
625 return ret;
626}
627
4698c8fe 628int access_or_die(const char *path, int mode, unsigned flag)
96b9e0e3
JN
629{
630 int ret = access(path, mode);
4698c8fe 631 if (ret && !access_error_is_ok(errno, flag))
96b9e0e3
JN
632 die_errno(_("unable to access '%s'"), path);
633 return ret;
634}
635
aa14e980
RS
636char *xgetcwd(void)
637{
638 struct strbuf sb = STRBUF_INIT;
639 if (strbuf_getcwd(&sb))
640 die_errno(_("unable to get current working directory"));
641 return strbuf_detach(&sb, NULL);
642}
316e53e6 643
7b03c89e
JK
644int xsnprintf(char *dst, size_t max, const char *fmt, ...)
645{
646 va_list ap;
647 int len;
648
649 va_start(ap, fmt);
650 len = vsnprintf(dst, max, fmt, ap);
651 va_end(ap);
652
653 if (len < 0)
654 die("BUG: your snprintf is broken");
655 if (len >= max)
656 die("BUG: attempt to snprintf into too-small buffer");
657 return len;
658}
659
12d6ce1d
JH
660static int write_file_v(const char *path, int fatal,
661 const char *fmt, va_list params)
316e53e6
NTND
662{
663 struct strbuf sb = STRBUF_INIT;
316e53e6
NTND
664 int fd = open(path, O_RDWR | O_CREAT | O_TRUNC, 0666);
665 if (fd < 0) {
666 if (fatal)
667 die_errno(_("could not open %s for writing"), path);
668 return -1;
669 }
316e53e6 670 strbuf_vaddf(&sb, fmt, params);
e7ffa38c 671 strbuf_complete_line(&sb);
316e53e6
NTND
672 if (write_in_full(fd, sb.buf, sb.len) != sb.len) {
673 int err = errno;
674 close(fd);
675 strbuf_release(&sb);
676 errno = err;
677 if (fatal)
678 die_errno(_("could not write to %s"), path);
679 return -1;
680 }
681 strbuf_release(&sb);
682 if (close(fd)) {
683 if (fatal)
684 die_errno(_("could not close %s"), path);
685 return -1;
686 }
687 return 0;
688}
2024d317 689
12d6ce1d
JH
690int write_file(const char *path, const char *fmt, ...)
691{
692 int status;
693 va_list params;
694
695 va_start(params, fmt);
696 status = write_file_v(path, 1, fmt, params);
697 va_end(params);
698 return status;
699}
700
701int write_file_gently(const char *path, const char *fmt, ...)
702{
703 int status;
704 va_list params;
705
706 va_start(params, fmt);
707 status = write_file_v(path, 0, fmt, params);
708 va_end(params);
709 return status;
710}
711
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712void sleep_millisec(int millisec)
713{
714 poll(NULL, 0, millisec);
715}