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[thirdparty/git.git] / git-compat-util.h
1 #ifndef GIT_COMPAT_UTIL_H
2 #define GIT_COMPAT_UTIL_H
3
4 #if __STDC_VERSION__ - 0 < 199901L
5 /*
6 * Git is in a testing period for mandatory C99 support in the compiler. If
7 * your compiler is reasonably recent, you can try to enable C99 support (or,
8 * for MSVC, C11 support). If you encounter a problem and can't enable C99
9 * support with your compiler (such as with "-std=gnu99") and don't have access
10 * to one with this support, such as GCC or Clang, you can remove this #if
11 * directive, but please report the details of your system to
12 * git@vger.kernel.org.
13 */
14 #error "Required C99 support is in a test phase. Please see git-compat-util.h for more details."
15 #endif
16
17 #ifdef USE_MSVC_CRTDBG
18 /*
19 * For these to work they must appear very early in each
20 * file -- before most of the standard header files.
21 */
22 #include <stdlib.h>
23 #include <crtdbg.h>
24 #endif
25
26 struct strbuf;
27
28
29 #define _FILE_OFFSET_BITS 64
30
31
32 /* Derived from Linux "Features Test Macro" header
33 * Convenience macros to test the versions of gcc (or
34 * a compatible compiler).
35 * Use them like this:
36 * #if GIT_GNUC_PREREQ (2,8)
37 * ... code requiring gcc 2.8 or later ...
38 * #endif
39 */
40 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
41 # define GIT_GNUC_PREREQ(maj, min) \
42 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
43 #else
44 #define GIT_GNUC_PREREQ(maj, min) 0
45 #endif
46
47
48 #ifndef FLEX_ARRAY
49 /*
50 * See if our compiler is known to support flexible array members.
51 */
52
53 /*
54 * Check vendor specific quirks first, before checking the
55 * __STDC_VERSION__, as vendor compilers can lie and we need to be
56 * able to work them around. Note that by not defining FLEX_ARRAY
57 * here, we can fall back to use the "safer but a bit wasteful" one
58 * later.
59 */
60 #if defined(__SUNPRO_C) && (__SUNPRO_C <= 0x580)
61 #elif defined(__GNUC__)
62 # if (__GNUC__ >= 3)
63 # define FLEX_ARRAY /* empty */
64 # else
65 # define FLEX_ARRAY 0 /* older GNU extension */
66 # endif
67 #elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
68 # define FLEX_ARRAY /* empty */
69 #endif
70
71 /*
72 * Otherwise, default to safer but a bit wasteful traditional style
73 */
74 #ifndef FLEX_ARRAY
75 # define FLEX_ARRAY 1
76 #endif
77 #endif
78
79
80 /*
81 * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
82 * @cond: the compile-time condition which must be true.
83 *
84 * Your compile will fail if the condition isn't true, or can't be evaluated
85 * by the compiler. This can be used in an expression: its value is "0".
86 *
87 * Example:
88 * #define foo_to_char(foo) \
89 * ((char *)(foo) \
90 * + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
91 */
92 #define BUILD_ASSERT_OR_ZERO(cond) \
93 (sizeof(char [1 - 2*!(cond)]) - 1)
94
95 #if GIT_GNUC_PREREQ(3, 1)
96 /* &arr[0] degrades to a pointer: a different type from an array */
97 # define BARF_UNLESS_AN_ARRAY(arr) \
98 BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
99 __typeof__(&(arr)[0])))
100 #else
101 # define BARF_UNLESS_AN_ARRAY(arr) 0
102 #endif
103 /*
104 * ARRAY_SIZE - get the number of elements in a visible array
105 * @x: the array whose size you want.
106 *
107 * This does not work on pointers, or arrays declared as [], or
108 * function parameters. With correct compiler support, such usage
109 * will cause a build error (see the build_assert_or_zero macro).
110 */
111 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
112
113 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
114
115 #define maximum_signed_value_of_type(a) \
116 (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
117
118 #define maximum_unsigned_value_of_type(a) \
119 (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
120
121 /*
122 * Signed integer overflow is undefined in C, so here's a helper macro
123 * to detect if the sum of two integers will overflow.
124 *
125 * Requires: a >= 0, typeof(a) equals typeof(b)
126 */
127 #define signed_add_overflows(a, b) \
128 ((b) > maximum_signed_value_of_type(a) - (a))
129
130 #define unsigned_add_overflows(a, b) \
131 ((b) > maximum_unsigned_value_of_type(a) - (a))
132
133 /*
134 * Returns true if the multiplication of "a" and "b" will
135 * overflow. The types of "a" and "b" must match and must be unsigned.
136 * Note that this macro evaluates "a" twice!
137 */
138 #define unsigned_mult_overflows(a, b) \
139 ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
140
141 /*
142 * Returns true if the left shift of "a" by "shift" bits will
143 * overflow. The type of "a" must be unsigned.
144 */
145 #define unsigned_left_shift_overflows(a, shift) \
146 ((shift) < bitsizeof(a) && \
147 (a) > maximum_unsigned_value_of_type(a) >> (shift))
148
149 #ifdef __GNUC__
150 #define TYPEOF(x) (__typeof__(x))
151 #else
152 #define TYPEOF(x)
153 #endif
154
155 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
156 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
157
158 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
159
160 /* Approximation of the length of the decimal representation of this type. */
161 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
162
163 #ifdef __MINGW64__
164 #define _POSIX_C_SOURCE 1
165 #elif defined(__sun__)
166 /*
167 * On Solaris, when _XOPEN_EXTENDED is set, its header file
168 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
169 * setting to say we are XPG5 or XPG6. Also on Solaris,
170 * XPG6 programs must be compiled with a c99 compiler, while
171 * non XPG6 programs must be compiled with a pre-c99 compiler.
172 */
173 # if __STDC_VERSION__ - 0 >= 199901L
174 # define _XOPEN_SOURCE 600
175 # else
176 # define _XOPEN_SOURCE 500
177 # endif
178 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
179 !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
180 !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
181 !defined(__CYGWIN__)
182 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
183 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
184 #endif
185 #define _ALL_SOURCE 1
186 #define _GNU_SOURCE 1
187 #define _BSD_SOURCE 1
188 #define _DEFAULT_SOURCE 1
189 #define _NETBSD_SOURCE 1
190 #define _SGI_SOURCE 1
191
192 #if GIT_GNUC_PREREQ(4, 5)
193 #define UNUSED __attribute__((unused)) \
194 __attribute__((deprecated ("parameter declared as UNUSED")))
195 #elif defined(__GNUC__)
196 #define UNUSED __attribute__((unused)) \
197 __attribute__((deprecated))
198 #else
199 #define UNUSED
200 #endif
201
202 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
203 # if !defined(_WIN32_WINNT)
204 # define _WIN32_WINNT 0x0600
205 # endif
206 #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
207 #include <winsock2.h>
208 #ifndef NO_UNIX_SOCKETS
209 #include <afunix.h>
210 #endif
211 #include <windows.h>
212 #define GIT_WINDOWS_NATIVE
213 #endif
214
215 #include <unistd.h>
216 #include <stdio.h>
217 #include <sys/stat.h>
218 #include <fcntl.h>
219 #include <stddef.h>
220 #include <stdlib.h>
221 #include <stdarg.h>
222 #include <string.h>
223 #ifdef HAVE_STRINGS_H
224 #include <strings.h> /* for strcasecmp() */
225 #endif
226 #include <errno.h>
227 #include <limits.h>
228 #ifdef NEEDS_SYS_PARAM_H
229 #include <sys/param.h>
230 #endif
231 #include <sys/types.h>
232 #include <dirent.h>
233 #include <sys/time.h>
234 #include <time.h>
235 #include <signal.h>
236 #include <assert.h>
237 #include <regex.h>
238 #include <utime.h>
239 #include <syslog.h>
240 #if !defined(NO_POLL_H)
241 #include <poll.h>
242 #elif !defined(NO_SYS_POLL_H)
243 #include <sys/poll.h>
244 #else
245 /* Pull the compat stuff */
246 #include <poll.h>
247 #endif
248 #ifdef HAVE_BSD_SYSCTL
249 #include <sys/sysctl.h>
250 #endif
251
252 /* Used by compat/win32/path-utils.h, and more */
253 static inline int is_xplatform_dir_sep(int c)
254 {
255 return c == '/' || c == '\\';
256 }
257
258 #if defined(__CYGWIN__)
259 #include "compat/win32/path-utils.h"
260 #endif
261 #if defined(__MINGW32__)
262 /* pull in Windows compatibility stuff */
263 #include "compat/win32/path-utils.h"
264 #include "compat/mingw.h"
265 #elif defined(_MSC_VER)
266 #include "compat/win32/path-utils.h"
267 #include "compat/msvc.h"
268 #else
269 #include <sys/utsname.h>
270 #include <sys/wait.h>
271 #include <sys/resource.h>
272 #include <sys/socket.h>
273 #include <sys/ioctl.h>
274 #include <sys/statvfs.h>
275 #include <termios.h>
276 #ifndef NO_SYS_SELECT_H
277 #include <sys/select.h>
278 #endif
279 #include <netinet/in.h>
280 #include <netinet/tcp.h>
281 #include <arpa/inet.h>
282 #include <netdb.h>
283 #include <pwd.h>
284 #include <sys/un.h>
285 #ifndef NO_INTTYPES_H
286 #include <inttypes.h>
287 #else
288 #include <stdint.h>
289 #endif
290 #ifdef HAVE_ARC4RANDOM_LIBBSD
291 #include <bsd/stdlib.h>
292 #endif
293 #ifdef HAVE_GETRANDOM
294 #include <sys/random.h>
295 #endif
296 #ifdef NO_INTPTR_T
297 /*
298 * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
299 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
300 * while on IP16 and IP16L32 it is "int" (resp. "short")
301 * Size needs to match (or exceed) 'sizeof(void *)'.
302 * We can't take "long long" here as not everybody has it.
303 */
304 typedef long intptr_t;
305 typedef unsigned long uintptr_t;
306 #endif
307 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
308 #include <grp.h>
309 #define _ALL_SOURCE 1
310 #endif
311
312 /* used on Mac OS X */
313 #ifdef PRECOMPOSE_UNICODE
314 #include "compat/precompose_utf8.h"
315 #else
316 static inline const char *precompose_argv_prefix(int argc, const char **argv, const char *prefix)
317 {
318 return prefix;
319 }
320 static inline const char *precompose_string_if_needed(const char *in)
321 {
322 return in;
323 }
324
325 #define probe_utf8_pathname_composition()
326 #endif
327
328 #ifdef MKDIR_WO_TRAILING_SLASH
329 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
330 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
331 #endif
332
333 #ifdef NO_STRUCT_ITIMERVAL
334 struct itimerval {
335 struct timeval it_interval;
336 struct timeval it_value;
337 };
338 #endif
339
340 #ifdef NO_SETITIMER
341 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
342 return 0; /* pretend success */
343 }
344 #endif
345
346 #ifndef NO_LIBGEN_H
347 #include <libgen.h>
348 #else
349 #define basename gitbasename
350 char *gitbasename(char *);
351 #define dirname gitdirname
352 char *gitdirname(char *);
353 #endif
354
355 #ifndef NO_ICONV
356 #include <iconv.h>
357 #endif
358
359 #ifndef NO_OPENSSL
360 #ifdef __APPLE__
361 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
362 #include <AvailabilityMacros.h>
363 #undef DEPRECATED_ATTRIBUTE
364 #define DEPRECATED_ATTRIBUTE
365 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
366 #endif
367 #include <openssl/ssl.h>
368 #include <openssl/err.h>
369 #endif
370
371 #ifdef HAVE_SYSINFO
372 # include <sys/sysinfo.h>
373 #endif
374
375 /* On most systems <netdb.h> would have given us this, but
376 * not on some systems (e.g. z/OS).
377 */
378 #ifndef NI_MAXHOST
379 #define NI_MAXHOST 1025
380 #endif
381
382 #ifndef NI_MAXSERV
383 #define NI_MAXSERV 32
384 #endif
385
386 /* On most systems <limits.h> would have given us this, but
387 * not on some systems (e.g. GNU/Hurd).
388 */
389 #ifndef PATH_MAX
390 #define PATH_MAX 4096
391 #endif
392
393 typedef uintmax_t timestamp_t;
394 #define PRItime PRIuMAX
395 #define parse_timestamp strtoumax
396 #define TIME_MAX UINTMAX_MAX
397 #define TIME_MIN 0
398
399 #ifndef PATH_SEP
400 #define PATH_SEP ':'
401 #endif
402
403 #ifdef HAVE_PATHS_H
404 #include <paths.h>
405 #endif
406 #ifndef _PATH_DEFPATH
407 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
408 #endif
409
410 #ifndef platform_core_config
411 static inline int noop_core_config(const char *var UNUSED,
412 const char *value UNUSED,
413 void *cb UNUSED)
414 {
415 return 0;
416 }
417 #define platform_core_config noop_core_config
418 #endif
419
420 int lstat_cache_aware_rmdir(const char *path);
421 #if !defined(__MINGW32__) && !defined(_MSC_VER)
422 #define rmdir lstat_cache_aware_rmdir
423 #endif
424
425 #ifndef has_dos_drive_prefix
426 static inline int git_has_dos_drive_prefix(const char *path)
427 {
428 return 0;
429 }
430 #define has_dos_drive_prefix git_has_dos_drive_prefix
431 #endif
432
433 #ifndef skip_dos_drive_prefix
434 static inline int git_skip_dos_drive_prefix(char **path)
435 {
436 return 0;
437 }
438 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
439 #endif
440
441 static inline int git_is_dir_sep(int c)
442 {
443 return c == '/';
444 }
445 #ifndef is_dir_sep
446 #define is_dir_sep git_is_dir_sep
447 #endif
448
449 #ifndef offset_1st_component
450 static inline int git_offset_1st_component(const char *path)
451 {
452 return is_dir_sep(path[0]);
453 }
454 #define offset_1st_component git_offset_1st_component
455 #endif
456
457 #ifndef is_valid_path
458 #define is_valid_path(path) 1
459 #endif
460
461 #ifndef is_path_owned_by_current_user
462
463 #ifdef __TANDEM
464 #define ROOT_UID 65535
465 #else
466 #define ROOT_UID 0
467 #endif
468
469 /*
470 * Do not use this function when
471 * (1) geteuid() did not say we are running as 'root', or
472 * (2) using this function will compromise the system.
473 *
474 * PORTABILITY WARNING:
475 * This code assumes uid_t is unsigned because that is what sudo does.
476 * If your uid_t type is signed and all your ids are positive then it
477 * should all work fine.
478 * If your version of sudo uses negative values for uid_t or it is
479 * buggy and return an overflowed value in SUDO_UID, then git might
480 * fail to grant access to your repository properly or even mistakenly
481 * grant access to someone else.
482 * In the unlikely scenario this happened to you, and that is how you
483 * got to this message, we would like to know about it; so sent us an
484 * email to git@vger.kernel.org indicating which platform you are
485 * using and which version of sudo, so we can improve this logic and
486 * maybe provide you with a patch that would prevent this issue again
487 * in the future.
488 */
489 static inline void extract_id_from_env(const char *env, uid_t *id)
490 {
491 const char *real_uid = getenv(env);
492
493 /* discard anything empty to avoid a more complex check below */
494 if (real_uid && *real_uid) {
495 char *endptr = NULL;
496 unsigned long env_id;
497
498 errno = 0;
499 /* silent overflow errors could trigger a bug here */
500 env_id = strtoul(real_uid, &endptr, 10);
501 if (!*endptr && !errno)
502 *id = env_id;
503 }
504 }
505
506 static inline int is_path_owned_by_current_uid(const char *path,
507 struct strbuf *report UNUSED)
508 {
509 struct stat st;
510 uid_t euid;
511
512 if (lstat(path, &st))
513 return 0;
514
515 euid = geteuid();
516 if (euid == ROOT_UID)
517 {
518 if (st.st_uid == ROOT_UID)
519 return 1;
520 else
521 extract_id_from_env("SUDO_UID", &euid);
522 }
523
524 return st.st_uid == euid;
525 }
526
527 #define is_path_owned_by_current_user is_path_owned_by_current_uid
528 #endif
529
530 #ifndef find_last_dir_sep
531 static inline char *git_find_last_dir_sep(const char *path)
532 {
533 return strrchr(path, '/');
534 }
535 #define find_last_dir_sep git_find_last_dir_sep
536 #endif
537
538 #ifndef has_dir_sep
539 static inline int git_has_dir_sep(const char *path)
540 {
541 return !!strchr(path, '/');
542 }
543 #define has_dir_sep(path) git_has_dir_sep(path)
544 #endif
545
546 #ifndef query_user_email
547 #define query_user_email() NULL
548 #endif
549
550 #ifdef __TANDEM
551 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
552 #include <floss.h(floss_getpwuid)>
553 #ifndef NSIG
554 /*
555 * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
556 * known, by detective work using kill -l as a list is all signals
557 * instead of signal.h where it should be.
558 */
559 # define NSIG 100
560 #endif
561 #endif
562
563 #if defined(__HP_cc) && (__HP_cc >= 61000)
564 #define NORETURN __attribute__((noreturn))
565 #define NORETURN_PTR
566 #elif defined(__GNUC__) && !defined(NO_NORETURN)
567 #define NORETURN __attribute__((__noreturn__))
568 #define NORETURN_PTR __attribute__((__noreturn__))
569 #elif defined(_MSC_VER)
570 #define NORETURN __declspec(noreturn)
571 #define NORETURN_PTR
572 #else
573 #define NORETURN
574 #define NORETURN_PTR
575 #ifndef __GNUC__
576 #ifndef __attribute__
577 #define __attribute__(x)
578 #endif
579 #endif
580 #endif
581
582 /* The sentinel attribute is valid from gcc version 4.0 */
583 #if defined(__GNUC__) && (__GNUC__ >= 4)
584 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
585 /* warn_unused_result exists as of gcc 3.4.0, but be lazy and check 4.0 */
586 #define RESULT_MUST_BE_USED __attribute__ ((warn_unused_result))
587 #else
588 #define LAST_ARG_MUST_BE_NULL
589 #define RESULT_MUST_BE_USED
590 #endif
591
592 #define MAYBE_UNUSED __attribute__((__unused__))
593
594 #include "compat/bswap.h"
595
596 #include "wildmatch.h"
597
598 struct strbuf;
599
600 /* General helper functions */
601 NORETURN void usage(const char *err);
602 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
603 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
604 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
605 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
606 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
607 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
608 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
609 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
610 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
611
612 #ifndef NO_OPENSSL
613 #ifdef APPLE_COMMON_CRYPTO
614 #include "compat/apple-common-crypto.h"
615 #else
616 #include <openssl/evp.h>
617 #include <openssl/hmac.h>
618 #endif /* APPLE_COMMON_CRYPTO */
619 #include <openssl/x509v3.h>
620 #endif /* NO_OPENSSL */
621
622 #ifdef HAVE_OPENSSL_CSPRNG
623 #include <openssl/rand.h>
624 #endif
625
626 /*
627 * Let callers be aware of the constant return value; this can help
628 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
629 * because other compilers may be confused by this.
630 */
631 #if defined(__GNUC__)
632 static inline int const_error(void)
633 {
634 return -1;
635 }
636 #define error(...) (error(__VA_ARGS__), const_error())
637 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
638 #endif
639
640 typedef void (*report_fn)(const char *, va_list params);
641
642 void set_die_routine(NORETURN_PTR report_fn routine);
643 report_fn get_die_message_routine(void);
644 void set_error_routine(report_fn routine);
645 report_fn get_error_routine(void);
646 void set_warn_routine(report_fn routine);
647 report_fn get_warn_routine(void);
648 void set_die_is_recursing_routine(int (*routine)(void));
649
650 int starts_with(const char *str, const char *prefix);
651 int istarts_with(const char *str, const char *prefix);
652
653 /*
654 * If the string "str" begins with the string found in "prefix", return 1.
655 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
656 * the string right after the prefix).
657 *
658 * Otherwise, return 0 and leave "out" untouched.
659 *
660 * Examples:
661 *
662 * [extract branch name, fail if not a branch]
663 * if (!skip_prefix(ref, "refs/heads/", &branch)
664 * return -1;
665 *
666 * [skip prefix if present, otherwise use whole string]
667 * skip_prefix(name, "refs/heads/", &name);
668 */
669 static inline int skip_prefix(const char *str, const char *prefix,
670 const char **out)
671 {
672 do {
673 if (!*prefix) {
674 *out = str;
675 return 1;
676 }
677 } while (*str++ == *prefix++);
678 return 0;
679 }
680
681 /*
682 * If the string "str" is the same as the string in "prefix", then the "arg"
683 * parameter is set to the "def" parameter and 1 is returned.
684 * If the string "str" begins with the string found in "prefix" and then a
685 * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
686 * (i.e., to the point in the string right after the prefix and the "=" sign),
687 * and 1 is returned.
688 *
689 * Otherwise, return 0 and leave "arg" untouched.
690 *
691 * When we accept both a "--key" and a "--key=<val>" option, this function
692 * can be used instead of !strcmp(arg, "--key") and then
693 * skip_prefix(arg, "--key=", &arg) to parse such an option.
694 */
695 int skip_to_optional_arg_default(const char *str, const char *prefix,
696 const char **arg, const char *def);
697
698 static inline int skip_to_optional_arg(const char *str, const char *prefix,
699 const char **arg)
700 {
701 return skip_to_optional_arg_default(str, prefix, arg, "");
702 }
703
704 /*
705 * Like skip_prefix, but promises never to read past "len" bytes of the input
706 * buffer, and returns the remaining number of bytes in "out" via "outlen".
707 */
708 static inline int skip_prefix_mem(const char *buf, size_t len,
709 const char *prefix,
710 const char **out, size_t *outlen)
711 {
712 size_t prefix_len = strlen(prefix);
713 if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
714 *out = buf + prefix_len;
715 *outlen = len - prefix_len;
716 return 1;
717 }
718 return 0;
719 }
720
721 /*
722 * If buf ends with suffix, return 1 and subtract the length of the suffix
723 * from *len. Otherwise, return 0 and leave *len untouched.
724 */
725 static inline int strip_suffix_mem(const char *buf, size_t *len,
726 const char *suffix)
727 {
728 size_t suflen = strlen(suffix);
729 if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
730 return 0;
731 *len -= suflen;
732 return 1;
733 }
734
735 /*
736 * If str ends with suffix, return 1 and set *len to the size of the string
737 * without the suffix. Otherwise, return 0 and set *len to the size of the
738 * string.
739 *
740 * Note that we do _not_ NUL-terminate str to the new length.
741 */
742 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
743 {
744 *len = strlen(str);
745 return strip_suffix_mem(str, len, suffix);
746 }
747
748 static inline int ends_with(const char *str, const char *suffix)
749 {
750 size_t len;
751 return strip_suffix(str, suffix, &len);
752 }
753
754 #define SWAP(a, b) do { \
755 void *_swap_a_ptr = &(a); \
756 void *_swap_b_ptr = &(b); \
757 unsigned char _swap_buffer[sizeof(a)]; \
758 memcpy(_swap_buffer, _swap_a_ptr, sizeof(a)); \
759 memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) + \
760 BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b))); \
761 memcpy(_swap_b_ptr, _swap_buffer, sizeof(a)); \
762 } while (0)
763
764 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
765
766 #ifndef PROT_READ
767 #define PROT_READ 1
768 #define PROT_WRITE 2
769 #define MAP_PRIVATE 1
770 #endif
771
772 #define mmap git_mmap
773 #define munmap git_munmap
774 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
775 int git_munmap(void *start, size_t length);
776
777 #else /* NO_MMAP || USE_WIN32_MMAP */
778
779 #include <sys/mman.h>
780
781 #endif /* NO_MMAP || USE_WIN32_MMAP */
782
783 #ifdef NO_MMAP
784
785 /* This value must be multiple of (pagesize * 2) */
786 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
787
788 #else /* NO_MMAP */
789
790 /* This value must be multiple of (pagesize * 2) */
791 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
792 (sizeof(void*) >= 8 \
793 ? 1 * 1024 * 1024 * 1024 \
794 : 32 * 1024 * 1024)
795
796 #endif /* NO_MMAP */
797
798 #ifndef MAP_FAILED
799 #define MAP_FAILED ((void *)-1)
800 #endif
801
802 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
803 #define on_disk_bytes(st) ((st).st_size)
804 #else
805 #define on_disk_bytes(st) ((st).st_blocks * 512)
806 #endif
807
808 #ifdef NEEDS_MODE_TRANSLATION
809 #undef S_IFMT
810 #undef S_IFREG
811 #undef S_IFDIR
812 #undef S_IFLNK
813 #undef S_IFBLK
814 #undef S_IFCHR
815 #undef S_IFIFO
816 #undef S_IFSOCK
817 #define S_IFMT 0170000
818 #define S_IFREG 0100000
819 #define S_IFDIR 0040000
820 #define S_IFLNK 0120000
821 #define S_IFBLK 0060000
822 #define S_IFCHR 0020000
823 #define S_IFIFO 0010000
824 #define S_IFSOCK 0140000
825 #ifdef stat
826 #undef stat
827 #endif
828 #define stat(path, buf) git_stat(path, buf)
829 int git_stat(const char *, struct stat *);
830 #ifdef fstat
831 #undef fstat
832 #endif
833 #define fstat(fd, buf) git_fstat(fd, buf)
834 int git_fstat(int, struct stat *);
835 #ifdef lstat
836 #undef lstat
837 #endif
838 #define lstat(path, buf) git_lstat(path, buf)
839 int git_lstat(const char *, struct stat *);
840 #endif
841
842 #define DEFAULT_PACKED_GIT_LIMIT \
843 ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
844
845 #ifdef NO_PREAD
846 #define pread git_pread
847 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
848 #endif
849 /*
850 * Forward decl that will remind us if its twin in cache.h changes.
851 * This function is used in compat/pread.c. But we can't include
852 * cache.h there.
853 */
854 ssize_t read_in_full(int fd, void *buf, size_t count);
855
856 #ifdef NO_SETENV
857 #define setenv gitsetenv
858 int gitsetenv(const char *, const char *, int);
859 #endif
860
861 #ifdef NO_MKDTEMP
862 #define mkdtemp gitmkdtemp
863 char *gitmkdtemp(char *);
864 #endif
865
866 #ifdef NO_UNSETENV
867 #define unsetenv gitunsetenv
868 int gitunsetenv(const char *);
869 #endif
870
871 #ifdef NO_STRCASESTR
872 #define strcasestr gitstrcasestr
873 char *gitstrcasestr(const char *haystack, const char *needle);
874 #endif
875
876 #ifdef NO_STRLCPY
877 #define strlcpy gitstrlcpy
878 size_t gitstrlcpy(char *, const char *, size_t);
879 #endif
880
881 #ifdef NO_STRTOUMAX
882 #define strtoumax gitstrtoumax
883 uintmax_t gitstrtoumax(const char *, char **, int);
884 #define strtoimax gitstrtoimax
885 intmax_t gitstrtoimax(const char *, char **, int);
886 #endif
887
888 #ifdef NO_HSTRERROR
889 #define hstrerror githstrerror
890 const char *githstrerror(int herror);
891 #endif
892
893 #ifdef NO_MEMMEM
894 #define memmem gitmemmem
895 void *gitmemmem(const void *haystack, size_t haystacklen,
896 const void *needle, size_t needlelen);
897 #endif
898
899 #ifdef OVERRIDE_STRDUP
900 #ifdef strdup
901 #undef strdup
902 #endif
903 #define strdup gitstrdup
904 char *gitstrdup(const char *s);
905 #endif
906
907 #ifdef NO_GETPAGESIZE
908 #define getpagesize() sysconf(_SC_PAGESIZE)
909 #endif
910
911 #ifndef O_CLOEXEC
912 #define O_CLOEXEC 0
913 #endif
914
915 #ifdef FREAD_READS_DIRECTORIES
916 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
917 # ifdef fopen
918 # undef fopen
919 # endif
920 # define fopen(a,b) git_fopen(a,b)
921 # endif
922 FILE *git_fopen(const char*, const char*);
923 #endif
924
925 #ifdef SNPRINTF_RETURNS_BOGUS
926 #ifdef snprintf
927 #undef snprintf
928 #endif
929 #define snprintf git_snprintf
930 int git_snprintf(char *str, size_t maxsize,
931 const char *format, ...);
932 #ifdef vsnprintf
933 #undef vsnprintf
934 #endif
935 #define vsnprintf git_vsnprintf
936 int git_vsnprintf(char *str, size_t maxsize,
937 const char *format, va_list ap);
938 #endif
939
940 #ifdef OPEN_RETURNS_EINTR
941 #undef open
942 #define open git_open_with_retry
943 int git_open_with_retry(const char *path, int flag, ...);
944 #endif
945
946 #ifdef __GLIBC_PREREQ
947 #if __GLIBC_PREREQ(2, 1)
948 #define HAVE_STRCHRNUL
949 #endif
950 #endif
951
952 #ifndef HAVE_STRCHRNUL
953 #define strchrnul gitstrchrnul
954 static inline char *gitstrchrnul(const char *s, int c)
955 {
956 while (*s && *s != c)
957 s++;
958 return (char *)s;
959 }
960 #endif
961
962 #ifdef NO_INET_PTON
963 int inet_pton(int af, const char *src, void *dst);
964 #endif
965
966 #ifdef NO_INET_NTOP
967 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
968 #endif
969
970 #ifdef NO_PTHREADS
971 #define atexit git_atexit
972 int git_atexit(void (*handler)(void));
973 #endif
974
975 static inline size_t st_add(size_t a, size_t b)
976 {
977 if (unsigned_add_overflows(a, b))
978 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
979 (uintmax_t)a, (uintmax_t)b);
980 return a + b;
981 }
982 #define st_add3(a,b,c) st_add(st_add((a),(b)),(c))
983 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
984
985 static inline size_t st_mult(size_t a, size_t b)
986 {
987 if (unsigned_mult_overflows(a, b))
988 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
989 (uintmax_t)a, (uintmax_t)b);
990 return a * b;
991 }
992
993 static inline size_t st_sub(size_t a, size_t b)
994 {
995 if (a < b)
996 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
997 (uintmax_t)a, (uintmax_t)b);
998 return a - b;
999 }
1000
1001 static inline size_t st_left_shift(size_t a, unsigned shift)
1002 {
1003 if (unsigned_left_shift_overflows(a, shift))
1004 die("size_t overflow: %"PRIuMAX" << %u",
1005 (uintmax_t)a, shift);
1006 return a << shift;
1007 }
1008
1009 static inline unsigned long cast_size_t_to_ulong(size_t a)
1010 {
1011 if (a != (unsigned long)a)
1012 die("object too large to read on this platform: %"
1013 PRIuMAX" is cut off to %lu",
1014 (uintmax_t)a, (unsigned long)a);
1015 return (unsigned long)a;
1016 }
1017
1018 /*
1019 * Limit size of IO chunks, because huge chunks only cause pain. OS X
1020 * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
1021 * the absence of bugs, large chunks can result in bad latencies when
1022 * you decide to kill the process.
1023 *
1024 * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
1025 * that is smaller than that, clip it to SSIZE_MAX, as a call to
1026 * read(2) or write(2) larger than that is allowed to fail. As the last
1027 * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
1028 * to override this, if the definition of SSIZE_MAX given by the platform
1029 * is broken.
1030 */
1031 #ifndef MAX_IO_SIZE
1032 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
1033 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
1034 # define MAX_IO_SIZE SSIZE_MAX
1035 # else
1036 # define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
1037 # endif
1038 #endif
1039
1040 #ifdef HAVE_ALLOCA_H
1041 # include <alloca.h>
1042 # define xalloca(size) (alloca(size))
1043 # define xalloca_free(p) do {} while (0)
1044 #else
1045 # define xalloca(size) (xmalloc(size))
1046 # define xalloca_free(p) (free(p))
1047 #endif
1048 char *xstrdup(const char *str);
1049 void *xmalloc(size_t size);
1050 void *xmallocz(size_t size);
1051 void *xmallocz_gently(size_t size);
1052 void *xmemdupz(const void *data, size_t len);
1053 char *xstrndup(const char *str, size_t len);
1054 void *xrealloc(void *ptr, size_t size);
1055 void *xcalloc(size_t nmemb, size_t size);
1056 void xsetenv(const char *name, const char *value, int overwrite);
1057 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1058 const char *mmap_os_err(void);
1059 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1060 int xopen(const char *path, int flags, ...);
1061 ssize_t xread(int fd, void *buf, size_t len);
1062 ssize_t xwrite(int fd, const void *buf, size_t len);
1063 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
1064 int xdup(int fd);
1065 FILE *xfopen(const char *path, const char *mode);
1066 FILE *xfdopen(int fd, const char *mode);
1067 int xmkstemp(char *temp_filename);
1068 int xmkstemp_mode(char *temp_filename, int mode);
1069 char *xgetcwd(void);
1070 FILE *fopen_for_writing(const char *path);
1071 FILE *fopen_or_warn(const char *path, const char *mode);
1072
1073 /*
1074 * Like strncmp, but only return zero if s is NUL-terminated and exactly len
1075 * characters long. If it is not, consider it greater than t.
1076 */
1077 int xstrncmpz(const char *s, const char *t, size_t len);
1078
1079 /*
1080 * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
1081 * that ptr is used twice, so don't pass e.g. ptr++.
1082 */
1083 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
1084
1085 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
1086 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
1087 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
1088
1089 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
1090 BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1091 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
1092 {
1093 if (n)
1094 memcpy(dst, src, st_mult(size, n));
1095 }
1096
1097 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
1098 BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1099 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
1100 {
1101 if (n)
1102 memmove(dst, src, st_mult(size, n));
1103 }
1104
1105 /*
1106 * These functions help you allocate structs with flex arrays, and copy
1107 * the data directly into the array. For example, if you had:
1108 *
1109 * struct foo {
1110 * int bar;
1111 * char name[FLEX_ARRAY];
1112 * };
1113 *
1114 * you can do:
1115 *
1116 * struct foo *f;
1117 * FLEX_ALLOC_MEM(f, name, src, len);
1118 *
1119 * to allocate a "foo" with the contents of "src" in the "name" field.
1120 * The resulting struct is automatically zero'd, and the flex-array field
1121 * is NUL-terminated (whether the incoming src buffer was or not).
1122 *
1123 * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1124 * but do want to store a pointer to some extra data in the same allocated
1125 * block. For example, if you have:
1126 *
1127 * struct foo {
1128 * char *name;
1129 * int bar;
1130 * };
1131 *
1132 * you can do:
1133 *
1134 * struct foo *f;
1135 * FLEXPTR_ALLOC_STR(f, name, src);
1136 *
1137 * and "name" will point to a block of memory after the struct, which will be
1138 * freed along with the struct (but the pointer can be repointed anywhere).
1139 *
1140 * The *_STR variants accept a string parameter rather than a ptr/len
1141 * combination.
1142 *
1143 * Note that these macros will evaluate the first parameter multiple
1144 * times, and it must be assignable as an lvalue.
1145 */
1146 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1147 size_t flex_array_len_ = (len); \
1148 (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1149 memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1150 } while (0)
1151 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1152 size_t flex_array_len_ = (len); \
1153 (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1154 memcpy((x) + 1, (buf), flex_array_len_); \
1155 (x)->ptrname = (void *)((x)+1); \
1156 } while(0)
1157 #define FLEX_ALLOC_STR(x, flexname, str) \
1158 FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1159 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1160 FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1161
1162 static inline char *xstrdup_or_null(const char *str)
1163 {
1164 return str ? xstrdup(str) : NULL;
1165 }
1166
1167 static inline size_t xsize_t(off_t len)
1168 {
1169 if (len < 0 || (uintmax_t) len > SIZE_MAX)
1170 die("Cannot handle files this big");
1171 return (size_t) len;
1172 }
1173
1174 __attribute__((format (printf, 3, 4)))
1175 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1176
1177 #ifndef HOST_NAME_MAX
1178 #define HOST_NAME_MAX 256
1179 #endif
1180
1181 int xgethostname(char *buf, size_t len);
1182
1183 /* in ctype.c, for kwset users */
1184 extern const unsigned char tolower_trans_tbl[256];
1185
1186 /* Sane ctype - no locale, and works with signed chars */
1187 #undef isascii
1188 #undef isspace
1189 #undef isdigit
1190 #undef isalpha
1191 #undef isalnum
1192 #undef isprint
1193 #undef islower
1194 #undef isupper
1195 #undef tolower
1196 #undef toupper
1197 #undef iscntrl
1198 #undef ispunct
1199 #undef isxdigit
1200
1201 extern const unsigned char sane_ctype[256];
1202 #define GIT_SPACE 0x01
1203 #define GIT_DIGIT 0x02
1204 #define GIT_ALPHA 0x04
1205 #define GIT_GLOB_SPECIAL 0x08
1206 #define GIT_REGEX_SPECIAL 0x10
1207 #define GIT_PATHSPEC_MAGIC 0x20
1208 #define GIT_CNTRL 0x40
1209 #define GIT_PUNCT 0x80
1210 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1211 #define isascii(x) (((x) & ~0x7f) == 0)
1212 #define isspace(x) sane_istest(x,GIT_SPACE)
1213 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1214 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1215 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1216 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1217 #define islower(x) sane_iscase(x, 1)
1218 #define isupper(x) sane_iscase(x, 0)
1219 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1220 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1221 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1222 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1223 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1224 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1225 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1226 #define toupper(x) sane_case((unsigned char)(x), 0)
1227 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1228
1229 static inline int sane_case(int x, int high)
1230 {
1231 if (sane_istest(x, GIT_ALPHA))
1232 x = (x & ~0x20) | high;
1233 return x;
1234 }
1235
1236 static inline int sane_iscase(int x, int is_lower)
1237 {
1238 if (!sane_istest(x, GIT_ALPHA))
1239 return 0;
1240
1241 if (is_lower)
1242 return (x & 0x20) != 0;
1243 else
1244 return (x & 0x20) == 0;
1245 }
1246
1247 /*
1248 * Like skip_prefix, but compare case-insensitively. Note that the comparison
1249 * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1250 * locale-specific conversions).
1251 */
1252 static inline int skip_iprefix(const char *str, const char *prefix,
1253 const char **out)
1254 {
1255 do {
1256 if (!*prefix) {
1257 *out = str;
1258 return 1;
1259 }
1260 } while (tolower(*str++) == tolower(*prefix++));
1261 return 0;
1262 }
1263
1264 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1265 {
1266 unsigned long ul;
1267 char *p;
1268
1269 errno = 0;
1270 /* negative values would be accepted by strtoul */
1271 if (strchr(s, '-'))
1272 return -1;
1273 ul = strtoul(s, &p, base);
1274 if (errno || *p || p == s || (unsigned int) ul != ul)
1275 return -1;
1276 *result = ul;
1277 return 0;
1278 }
1279
1280 static inline int strtol_i(char const *s, int base, int *result)
1281 {
1282 long ul;
1283 char *p;
1284
1285 errno = 0;
1286 ul = strtol(s, &p, base);
1287 if (errno || *p || p == s || (int) ul != ul)
1288 return -1;
1289 *result = ul;
1290 return 0;
1291 }
1292
1293 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1294 int(*compar)(const void *, const void *));
1295 #ifdef INTERNAL_QSORT
1296 #define qsort git_stable_qsort
1297 #endif
1298
1299 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1300 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1301 int(*compar)(const void *, const void *))
1302 {
1303 if (nmemb > 1)
1304 qsort(base, nmemb, size, compar);
1305 }
1306
1307 #define STABLE_QSORT(base, n, compar) \
1308 git_stable_qsort((base), (n), sizeof(*(base)), compar)
1309
1310 #ifndef HAVE_ISO_QSORT_S
1311 int git_qsort_s(void *base, size_t nmemb, size_t size,
1312 int (*compar)(const void *, const void *, void *), void *ctx);
1313 #define qsort_s git_qsort_s
1314 #endif
1315
1316 #define QSORT_S(base, n, compar, ctx) do { \
1317 if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1318 BUG("qsort_s() failed"); \
1319 } while (0)
1320
1321 #ifndef REG_STARTEND
1322 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1323 #endif
1324
1325 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1326 size_t nmatch, regmatch_t pmatch[], int eflags)
1327 {
1328 assert(nmatch > 0 && pmatch);
1329 pmatch[0].rm_so = 0;
1330 pmatch[0].rm_eo = size;
1331 return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1332 }
1333
1334 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1335 # define FORCE_DIR_SET_GID S_ISGID
1336 #else
1337 # define FORCE_DIR_SET_GID 0
1338 #endif
1339
1340 #ifdef NO_NSEC
1341 #undef USE_NSEC
1342 #define ST_CTIME_NSEC(st) 0
1343 #define ST_MTIME_NSEC(st) 0
1344 #else
1345 #ifdef USE_ST_TIMESPEC
1346 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1347 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1348 #else
1349 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1350 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1351 #endif
1352 #endif
1353
1354 #ifdef UNRELIABLE_FSTAT
1355 #define fstat_is_reliable() 0
1356 #else
1357 #define fstat_is_reliable() 1
1358 #endif
1359
1360 #ifndef va_copy
1361 /*
1362 * Since an obvious implementation of va_list would be to make it a
1363 * pointer into the stack frame, a simple assignment will work on
1364 * many systems. But let's try to be more portable.
1365 */
1366 #ifdef __va_copy
1367 #define va_copy(dst, src) __va_copy(dst, src)
1368 #else
1369 #define va_copy(dst, src) ((dst) = (src))
1370 #endif
1371 #endif
1372
1373 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1374 extern int BUG_exit_code;
1375
1376 /* usage.c: if bug() is called we should have a BUG_if_bug() afterwards */
1377 extern int bug_called_must_BUG;
1378
1379 __attribute__((format (printf, 3, 4))) NORETURN
1380 void BUG_fl(const char *file, int line, const char *fmt, ...);
1381 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1382 __attribute__((format (printf, 3, 4)))
1383 void bug_fl(const char *file, int line, const char *fmt, ...);
1384 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)
1385 #define BUG_if_bug(...) do { \
1386 if (bug_called_must_BUG) \
1387 BUG_fl(__FILE__, __LINE__, __VA_ARGS__); \
1388 } while (0)
1389
1390 #ifndef FSYNC_METHOD_DEFAULT
1391 #ifdef __APPLE__
1392 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_WRITEOUT_ONLY
1393 #else
1394 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_FSYNC
1395 #endif
1396 #endif
1397
1398 enum fsync_action {
1399 FSYNC_WRITEOUT_ONLY,
1400 FSYNC_HARDWARE_FLUSH
1401 };
1402
1403 /*
1404 * Issues an fsync against the specified file according to the specified mode.
1405 *
1406 * FSYNC_WRITEOUT_ONLY attempts to use interfaces available on some operating
1407 * systems to flush the OS cache without issuing a flush command to the storage
1408 * controller. If those interfaces are unavailable, the function fails with
1409 * ENOSYS.
1410 *
1411 * FSYNC_HARDWARE_FLUSH does an OS writeout and hardware flush to ensure that
1412 * changes are durable. It is not expected to fail.
1413 */
1414 int git_fsync(int fd, enum fsync_action action);
1415
1416 /*
1417 * Writes out trace statistics for fsync using the trace2 API.
1418 */
1419 void trace_git_fsync_stats(void);
1420
1421 /*
1422 * Preserves errno, prints a message, but gives no warning for ENOENT.
1423 * Returns 0 on success, which includes trying to unlink an object that does
1424 * not exist.
1425 */
1426 int unlink_or_warn(const char *path);
1427 /*
1428 * Tries to unlink file. Returns 0 if unlink succeeded
1429 * or the file already didn't exist. Returns -1 and
1430 * appends a message to err suitable for
1431 * 'error("%s", err->buf)' on error.
1432 */
1433 int unlink_or_msg(const char *file, struct strbuf *err);
1434 /*
1435 * Preserves errno, prints a message, but gives no warning for ENOENT.
1436 * Returns 0 on success, which includes trying to remove a directory that does
1437 * not exist.
1438 */
1439 int rmdir_or_warn(const char *path);
1440 /*
1441 * Calls the correct function out of {unlink,rmdir}_or_warn based on
1442 * the supplied file mode.
1443 */
1444 int remove_or_warn(unsigned int mode, const char *path);
1445
1446 /*
1447 * Call access(2), but warn for any error except "missing file"
1448 * (ENOENT or ENOTDIR).
1449 */
1450 #define ACCESS_EACCES_OK (1U << 0)
1451 int access_or_warn(const char *path, int mode, unsigned flag);
1452 int access_or_die(const char *path, int mode, unsigned flag);
1453
1454 /* Warn on an inaccessible file if errno indicates this is an error */
1455 int warn_on_fopen_errors(const char *path);
1456
1457 /*
1458 * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1459 * may be racy. Do not use this as protection against an attacker who can
1460 * simultaneously create paths.
1461 */
1462 int open_nofollow(const char *path, int flags);
1463
1464 #ifndef SHELL_PATH
1465 # define SHELL_PATH "/bin/sh"
1466 #endif
1467
1468 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1469 static inline void flockfile(FILE *fh)
1470 {
1471 ; /* nothing */
1472 }
1473 static inline void funlockfile(FILE *fh)
1474 {
1475 ; /* nothing */
1476 }
1477 #define getc_unlocked(fh) getc(fh)
1478 #endif
1479
1480 #ifdef FILENO_IS_A_MACRO
1481 int git_fileno(FILE *stream);
1482 # ifndef COMPAT_CODE_FILENO
1483 # undef fileno
1484 # define fileno(p) git_fileno(p)
1485 # endif
1486 #endif
1487
1488 #ifdef NEED_ACCESS_ROOT_HANDLER
1489 int git_access(const char *path, int mode);
1490 # ifndef COMPAT_CODE_ACCESS
1491 # ifdef access
1492 # undef access
1493 # endif
1494 # define access(path, mode) git_access(path, mode)
1495 # endif
1496 #endif
1497
1498 /*
1499 * Our code often opens a path to an optional file, to work on its
1500 * contents when we can successfully open it. We can ignore a failure
1501 * to open if such an optional file does not exist, but we do want to
1502 * report a failure in opening for other reasons (e.g. we got an I/O
1503 * error, or the file is there, but we lack the permission to open).
1504 *
1505 * Call this function after seeing an error from open() or fopen() to
1506 * see if the errno indicates a missing file that we can safely ignore.
1507 */
1508 static inline int is_missing_file_error(int errno_)
1509 {
1510 return (errno_ == ENOENT || errno_ == ENOTDIR);
1511 }
1512
1513 int cmd_main(int, const char **);
1514
1515 /*
1516 * Intercept all calls to exit() and route them to trace2 to
1517 * optionally emit a message before calling the real exit().
1518 */
1519 int common_exit(const char *file, int line, int code);
1520 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
1521
1522 /*
1523 * You can mark a stack variable with UNLEAK(var) to avoid it being
1524 * reported as a leak by tools like LSAN or valgrind. The argument
1525 * should generally be the variable itself (not its address and not what
1526 * it points to). It's safe to use this on pointers which may already
1527 * have been freed, or on pointers which may still be in use.
1528 *
1529 * Use this _only_ for a variable that leaks by going out of scope at
1530 * program exit (so only from cmd_* functions or their direct helpers).
1531 * Normal functions, especially those which may be called multiple
1532 * times, should actually free their memory. This is only meant as
1533 * an annotation, and does nothing in non-leak-checking builds.
1534 */
1535 #ifdef SUPPRESS_ANNOTATED_LEAKS
1536 void unleak_memory(const void *ptr, size_t len);
1537 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1538 #else
1539 #define UNLEAK(var) do {} while (0)
1540 #endif
1541
1542 #define z_const
1543 #include <zlib.h>
1544
1545 #if ZLIB_VERNUM < 0x1290
1546 /*
1547 * This is uncompress2, which is only available in zlib >= 1.2.9
1548 * (released as of early 2017). See compat/zlib-uncompress2.c.
1549 */
1550 int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
1551 uLong *sourceLen);
1552 #endif
1553
1554 /*
1555 * This include must come after system headers, since it introduces macros that
1556 * replace system names.
1557 */
1558 #include "banned.h"
1559
1560 /*
1561 * container_of - Get the address of an object containing a field.
1562 *
1563 * @ptr: pointer to the field.
1564 * @type: type of the object.
1565 * @member: name of the field within the object.
1566 */
1567 #define container_of(ptr, type, member) \
1568 ((type *) ((char *)(ptr) - offsetof(type, member)))
1569
1570 /*
1571 * helper function for `container_of_or_null' to avoid multiple
1572 * evaluation of @ptr
1573 */
1574 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1575 {
1576 return ptr ? (char *)ptr - offset : NULL;
1577 }
1578
1579 /*
1580 * like `container_of', but allows returned value to be NULL
1581 */
1582 #define container_of_or_null(ptr, type, member) \
1583 (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1584
1585 /*
1586 * like offsetof(), but takes a pointer to a variable of type which
1587 * contains @member, instead of a specified type.
1588 * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1589 * everywhere.
1590 */
1591 #if defined(__GNUC__) /* clang sets this, too */
1592 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1593 #else /* !__GNUC__ */
1594 #define OFFSETOF_VAR(ptr, member) \
1595 ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1596 #endif /* !__GNUC__ */
1597
1598 void sleep_millisec(int millisec);
1599
1600 /*
1601 * Generate len bytes from the system cryptographically secure PRNG.
1602 * Returns 0 on success and -1 on error, setting errno. The inability to
1603 * satisfy the full request is an error.
1604 */
1605 int csprng_bytes(void *buf, size_t len);
1606
1607 #endif