1 #ifndef GIT_COMPAT_UTIL_H
2 #define GIT_COMPAT_UTIL_H
4 #if __STDC_VERSION__ - 0 < 199901L
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.
14 #error "Required C99 support is in a test phase. Please see git-compat-util.h for more details."
17 #ifdef USE_MSVC_CRTDBG
19 * For these to work they must appear very early in each
20 * file -- before most of the standard header files.
29 #define _FILE_OFFSET_BITS 64
32 /* Derived from Linux "Features Test Macro" header
33 * Convenience macros to test the versions of gcc (or
34 * a compatible compiler).
36 * #if GIT_GNUC_PREREQ (2,8)
37 * ... code requiring gcc 2.8 or later ...
40 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
41 # define GIT_GNUC_PREREQ(maj, min) \
42 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
44 #define GIT_GNUC_PREREQ(maj, min) 0
50 * See if our compiler is known to support flexible array members.
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
60 #if defined(__SUNPRO_C) && (__SUNPRO_C <= 0x580)
61 #elif defined(__GNUC__)
63 # define FLEX_ARRAY /* empty */
65 # define FLEX_ARRAY 0 /* older GNU extension */
67 #elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
68 # define FLEX_ARRAY /* empty */
72 * Otherwise, default to safer but a bit wasteful traditional style
81 * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
82 * @cond: the compile-time condition which must be true.
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".
88 * #define foo_to_char(foo) \
90 * + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
92 #define BUILD_ASSERT_OR_ZERO(cond) \
93 (sizeof(char [1 - 2*!(cond)]) - 1)
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 # define BARF_UNLESS_COPYABLE(dst, src) \
101 BUILD_ASSERT_OR_ZERO(__builtin_types_compatible_p(__typeof__(*(dst)), \
104 # define BARF_UNLESS_AN_ARRAY(arr) 0
105 # define BARF_UNLESS_COPYABLE(dst, src) \
106 BUILD_ASSERT_OR_ZERO(0 ? ((*(dst) = *(src)), 0) : \
107 sizeof(*(dst)) == sizeof(*(src)))
110 * ARRAY_SIZE - get the number of elements in a visible array
111 * @x: the array whose size you want.
113 * This does not work on pointers, or arrays declared as [], or
114 * function parameters. With correct compiler support, such usage
115 * will cause a build error (see the build_assert_or_zero macro).
117 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
119 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
121 #define maximum_signed_value_of_type(a) \
122 (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
124 #define maximum_unsigned_value_of_type(a) \
125 (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
128 * Signed integer overflow is undefined in C, so here's a helper macro
129 * to detect if the sum of two integers will overflow.
131 * Requires: a >= 0, typeof(a) equals typeof(b)
133 #define signed_add_overflows(a, b) \
134 ((b) > maximum_signed_value_of_type(a) - (a))
136 #define unsigned_add_overflows(a, b) \
137 ((b) > maximum_unsigned_value_of_type(a) - (a))
140 * Returns true if the multiplication of "a" and "b" will
141 * overflow. The types of "a" and "b" must match and must be unsigned.
142 * Note that this macro evaluates "a" twice!
144 #define unsigned_mult_overflows(a, b) \
145 ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
148 * Returns true if the left shift of "a" by "shift" bits will
149 * overflow. The type of "a" must be unsigned.
151 #define unsigned_left_shift_overflows(a, shift) \
152 ((shift) < bitsizeof(a) && \
153 (a) > maximum_unsigned_value_of_type(a) >> (shift))
156 #define TYPEOF(x) (__typeof__(x))
161 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
162 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
164 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
166 /* Approximation of the length of the decimal representation of this type. */
167 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
170 #define _POSIX_C_SOURCE 1
171 #elif defined(__sun__)
173 * On Solaris, when _XOPEN_EXTENDED is set, its header file
174 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
175 * setting to say we are XPG5 or XPG6. Also on Solaris,
176 * XPG6 programs must be compiled with a c99 compiler, while
177 * non XPG6 programs must be compiled with a pre-c99 compiler.
179 # if __STDC_VERSION__ - 0 >= 199901L
180 # define _XOPEN_SOURCE 600
182 # define _XOPEN_SOURCE 500
184 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
185 !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
186 !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
188 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
189 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
191 #define _ALL_SOURCE 1
192 #define _GNU_SOURCE 1
193 #define _BSD_SOURCE 1
194 #define _DEFAULT_SOURCE 1
195 #define _NETBSD_SOURCE 1
196 #define _SGI_SOURCE 1
198 #if GIT_GNUC_PREREQ(4, 5)
199 #define UNUSED __attribute__((unused)) \
200 __attribute__((deprecated ("parameter declared as UNUSED")))
201 #elif defined(__GNUC__)
202 #define UNUSED __attribute__((unused)) \
203 __attribute__((deprecated))
208 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
209 # if !defined(_WIN32_WINNT)
210 # define _WIN32_WINNT 0x0600
212 #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
213 #include <winsock2.h>
214 #ifndef NO_UNIX_SOCKETS
218 #define GIT_WINDOWS_NATIVE
223 #include <sys/stat.h>
229 #ifdef HAVE_STRINGS_H
230 #include <strings.h> /* for strcasecmp() */
235 #ifdef NEEDS_SYS_PARAM_H
236 #include <sys/param.h>
238 #include <sys/types.h>
240 #include <sys/time.h>
247 #if !defined(NO_POLL_H)
249 #elif !defined(NO_SYS_POLL_H)
250 #include <sys/poll.h>
252 /* Pull the compat stuff */
255 #ifdef HAVE_BSD_SYSCTL
256 #include <sys/sysctl.h>
259 /* Used by compat/win32/path-utils.h, and more */
260 static inline int is_xplatform_dir_sep(int c
)
262 return c
== '/' || c
== '\\';
265 #if defined(__CYGWIN__)
266 #include "compat/win32/path-utils.h"
268 #if defined(__MINGW32__)
269 /* pull in Windows compatibility stuff */
270 #include "compat/win32/path-utils.h"
271 #include "compat/mingw.h"
272 #elif defined(_MSC_VER)
273 #include "compat/win32/path-utils.h"
274 #include "compat/msvc.h"
276 #include <sys/utsname.h>
277 #include <sys/wait.h>
278 #include <sys/resource.h>
279 #include <sys/socket.h>
280 #include <sys/ioctl.h>
281 #include <sys/statvfs.h>
283 #ifndef NO_SYS_SELECT_H
284 #include <sys/select.h>
286 #include <netinet/in.h>
287 #include <netinet/tcp.h>
288 #include <arpa/inet.h>
292 #ifndef NO_INTTYPES_H
293 #include <inttypes.h>
297 #ifdef HAVE_ARC4RANDOM_LIBBSD
298 #include <bsd/stdlib.h>
300 #ifdef HAVE_GETRANDOM
301 #include <sys/random.h>
305 * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
306 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
307 * while on IP16 and IP16L32 it is "int" (resp. "short")
308 * Size needs to match (or exceed) 'sizeof(void *)'.
309 * We can't take "long long" here as not everybody has it.
311 typedef long intptr_t;
312 typedef unsigned long uintptr_t;
314 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
316 #define _ALL_SOURCE 1
319 /* used on Mac OS X */
320 #ifdef PRECOMPOSE_UNICODE
321 #include "compat/precompose_utf8.h"
323 static inline const char *precompose_argv_prefix(int argc UNUSED
,
324 const char **argv UNUSED
,
329 static inline const char *precompose_string_if_needed(const char *in
)
334 #define probe_utf8_pathname_composition()
337 #ifdef MKDIR_WO_TRAILING_SLASH
338 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
339 int compat_mkdir_wo_trailing_slash(const char*, mode_t
);
342 #ifdef NO_STRUCT_ITIMERVAL
344 struct timeval it_interval
;
345 struct timeval it_value
;
350 static inline int git_setitimer(int which UNUSED
,
351 const struct itimerval
*value UNUSED
,
352 struct itimerval
*newvalue UNUSED
) {
353 return 0; /* pretend success */
356 #define setitimer(which,value,ovalue) git_setitimer(which,value,ovalue)
362 #define basename gitbasename
363 char *gitbasename(char *);
364 #define dirname gitdirname
365 char *gitdirname(char *);
374 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
375 #include <AvailabilityMacros.h>
376 #undef DEPRECATED_ATTRIBUTE
377 #define DEPRECATED_ATTRIBUTE
378 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
380 #include <openssl/ssl.h>
381 #include <openssl/err.h>
385 # include <sys/sysinfo.h>
388 /* On most systems <netdb.h> would have given us this, but
389 * not on some systems (e.g. z/OS).
392 #define NI_MAXHOST 1025
396 #define NI_MAXSERV 32
399 /* On most systems <limits.h> would have given us this, but
400 * not on some systems (e.g. GNU/Hurd).
403 #define PATH_MAX 4096
406 typedef uintmax_t timestamp_t
;
407 #define PRItime PRIuMAX
408 #define parse_timestamp strtoumax
409 #define TIME_MAX UINTMAX_MAX
419 #ifndef _PATH_DEFPATH
420 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
423 #ifndef platform_core_config
424 static inline int noop_core_config(const char *var UNUSED
,
425 const char *value UNUSED
,
430 #define platform_core_config noop_core_config
433 int lstat_cache_aware_rmdir(const char *path
);
434 #if !defined(__MINGW32__) && !defined(_MSC_VER)
435 #define rmdir lstat_cache_aware_rmdir
438 #ifndef has_dos_drive_prefix
439 static inline int git_has_dos_drive_prefix(const char *path UNUSED
)
443 #define has_dos_drive_prefix git_has_dos_drive_prefix
446 #ifndef skip_dos_drive_prefix
447 static inline int git_skip_dos_drive_prefix(char **path UNUSED
)
451 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
454 static inline int git_is_dir_sep(int c
)
459 #define is_dir_sep git_is_dir_sep
462 #ifndef offset_1st_component
463 static inline int git_offset_1st_component(const char *path
)
465 return is_dir_sep(path
[0]);
467 #define offset_1st_component git_offset_1st_component
470 #ifndef is_valid_path
471 #define is_valid_path(path) 1
474 #ifndef is_path_owned_by_current_user
477 #define ROOT_UID 65535
483 * Do not use this function when
484 * (1) geteuid() did not say we are running as 'root', or
485 * (2) using this function will compromise the system.
487 * PORTABILITY WARNING:
488 * This code assumes uid_t is unsigned because that is what sudo does.
489 * If your uid_t type is signed and all your ids are positive then it
490 * should all work fine.
491 * If your version of sudo uses negative values for uid_t or it is
492 * buggy and return an overflowed value in SUDO_UID, then git might
493 * fail to grant access to your repository properly or even mistakenly
494 * grant access to someone else.
495 * In the unlikely scenario this happened to you, and that is how you
496 * got to this message, we would like to know about it; so sent us an
497 * email to git@vger.kernel.org indicating which platform you are
498 * using and which version of sudo, so we can improve this logic and
499 * maybe provide you with a patch that would prevent this issue again
502 static inline void extract_id_from_env(const char *env
, uid_t
*id
)
504 const char *real_uid
= getenv(env
);
506 /* discard anything empty to avoid a more complex check below */
507 if (real_uid
&& *real_uid
) {
509 unsigned long env_id
;
512 /* silent overflow errors could trigger a bug here */
513 env_id
= strtoul(real_uid
, &endptr
, 10);
514 if (!*endptr
&& !errno
)
519 static inline int is_path_owned_by_current_uid(const char *path
,
520 struct strbuf
*report UNUSED
)
525 if (lstat(path
, &st
))
529 if (euid
== ROOT_UID
)
531 if (st
.st_uid
== ROOT_UID
)
534 extract_id_from_env("SUDO_UID", &euid
);
537 return st
.st_uid
== euid
;
540 #define is_path_owned_by_current_user is_path_owned_by_current_uid
543 #ifndef find_last_dir_sep
544 static inline char *git_find_last_dir_sep(const char *path
)
546 return strrchr(path
, '/');
548 #define find_last_dir_sep git_find_last_dir_sep
552 static inline int git_has_dir_sep(const char *path
)
554 return !!strchr(path
, '/');
556 #define has_dir_sep(path) git_has_dir_sep(path)
559 #ifndef query_user_email
560 #define query_user_email() NULL
564 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
565 #include <floss.h(floss_getpwuid)>
568 * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
569 * known, by detective work using kill -l as a list is all signals
570 * instead of signal.h where it should be.
576 #if defined(__HP_cc) && (__HP_cc >= 61000)
577 #define NORETURN __attribute__((noreturn))
579 #elif defined(__GNUC__) && !defined(NO_NORETURN)
580 #define NORETURN __attribute__((__noreturn__))
581 #define NORETURN_PTR __attribute__((__noreturn__))
582 #elif defined(_MSC_VER)
583 #define NORETURN __declspec(noreturn)
589 #ifndef __attribute__
590 #define __attribute__(x)
595 /* The sentinel attribute is valid from gcc version 4.0 */
596 #if defined(__GNUC__) && (__GNUC__ >= 4)
597 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
598 /* warn_unused_result exists as of gcc 3.4.0, but be lazy and check 4.0 */
599 #define RESULT_MUST_BE_USED __attribute__ ((warn_unused_result))
601 #define LAST_ARG_MUST_BE_NULL
602 #define RESULT_MUST_BE_USED
605 #define MAYBE_UNUSED __attribute__((__unused__))
607 #include "compat/bswap.h"
609 #include "wildmatch.h"
613 /* General helper functions */
614 NORETURN
void usage(const char *err
);
615 NORETURN
void usagef(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
616 NORETURN
void die(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
617 NORETURN
void die_errno(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
618 int die_message(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
619 int die_message_errno(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
620 int error(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
621 int error_errno(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
622 void warning(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
623 void warning_errno(const char *err
, ...) __attribute__((format (printf
, 1, 2)));
626 #ifdef APPLE_COMMON_CRYPTO
627 #include "compat/apple-common-crypto.h"
629 #include <openssl/evp.h>
630 #include <openssl/hmac.h>
631 #endif /* APPLE_COMMON_CRYPTO */
632 #include <openssl/x509v3.h>
633 #endif /* NO_OPENSSL */
635 #ifdef HAVE_OPENSSL_CSPRNG
636 #include <openssl/rand.h>
640 * Let callers be aware of the constant return value; this can help
641 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
642 * because other compilers may be confused by this.
644 #if defined(__GNUC__)
645 static inline int const_error(void)
649 #define error(...) (error(__VA_ARGS__), const_error())
650 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
653 typedef void (*report_fn
)(const char *, va_list params
);
655 void set_die_routine(NORETURN_PTR report_fn routine
);
656 report_fn
get_die_message_routine(void);
657 void set_error_routine(report_fn routine
);
658 report_fn
get_error_routine(void);
659 void set_warn_routine(report_fn routine
);
660 report_fn
get_warn_routine(void);
661 void set_die_is_recursing_routine(int (*routine
)(void));
663 int starts_with(const char *str
, const char *prefix
);
664 int istarts_with(const char *str
, const char *prefix
);
667 * If the string "str" begins with the string found in "prefix", return 1.
668 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
669 * the string right after the prefix).
671 * Otherwise, return 0 and leave "out" untouched.
675 * [extract branch name, fail if not a branch]
676 * if (!skip_prefix(ref, "refs/heads/", &branch)
679 * [skip prefix if present, otherwise use whole string]
680 * skip_prefix(name, "refs/heads/", &name);
682 static inline int skip_prefix(const char *str
, const char *prefix
,
690 } while (*str
++ == *prefix
++);
695 * If the string "str" is the same as the string in "prefix", then the "arg"
696 * parameter is set to the "def" parameter and 1 is returned.
697 * If the string "str" begins with the string found in "prefix" and then a
698 * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
699 * (i.e., to the point in the string right after the prefix and the "=" sign),
702 * Otherwise, return 0 and leave "arg" untouched.
704 * When we accept both a "--key" and a "--key=<val>" option, this function
705 * can be used instead of !strcmp(arg, "--key") and then
706 * skip_prefix(arg, "--key=", &arg) to parse such an option.
708 int skip_to_optional_arg_default(const char *str
, const char *prefix
,
709 const char **arg
, const char *def
);
711 static inline int skip_to_optional_arg(const char *str
, const char *prefix
,
714 return skip_to_optional_arg_default(str
, prefix
, arg
, "");
718 * Like skip_prefix, but promises never to read past "len" bytes of the input
719 * buffer, and returns the remaining number of bytes in "out" via "outlen".
721 static inline int skip_prefix_mem(const char *buf
, size_t len
,
723 const char **out
, size_t *outlen
)
725 size_t prefix_len
= strlen(prefix
);
726 if (prefix_len
<= len
&& !memcmp(buf
, prefix
, prefix_len
)) {
727 *out
= buf
+ prefix_len
;
728 *outlen
= len
- prefix_len
;
735 * If buf ends with suffix, return 1 and subtract the length of the suffix
736 * from *len. Otherwise, return 0 and leave *len untouched.
738 static inline int strip_suffix_mem(const char *buf
, size_t *len
,
741 size_t suflen
= strlen(suffix
);
742 if (*len
< suflen
|| memcmp(buf
+ (*len
- suflen
), suffix
, suflen
))
749 * If str ends with suffix, return 1 and set *len to the size of the string
750 * without the suffix. Otherwise, return 0 and set *len to the size of the
753 * Note that we do _not_ NUL-terminate str to the new length.
755 static inline int strip_suffix(const char *str
, const char *suffix
, size_t *len
)
758 return strip_suffix_mem(str
, len
, suffix
);
761 static inline int ends_with(const char *str
, const char *suffix
)
764 return strip_suffix(str
, suffix
, &len
);
767 #define SWAP(a, b) do { \
768 void *_swap_a_ptr = &(a); \
769 void *_swap_b_ptr = &(b); \
770 unsigned char _swap_buffer[sizeof(a)]; \
771 memcpy(_swap_buffer, _swap_a_ptr, sizeof(a)); \
772 memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) + \
773 BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b))); \
774 memcpy(_swap_b_ptr, _swap_buffer, sizeof(a)); \
777 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
782 #define MAP_PRIVATE 1
785 #define mmap git_mmap
786 #define munmap git_munmap
787 void *git_mmap(void *start
, size_t length
, int prot
, int flags
, int fd
, off_t offset
);
788 int git_munmap(void *start
, size_t length
);
790 #else /* NO_MMAP || USE_WIN32_MMAP */
792 #include <sys/mman.h>
794 #endif /* NO_MMAP || USE_WIN32_MMAP */
798 /* This value must be multiple of (pagesize * 2) */
799 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
803 /* This value must be multiple of (pagesize * 2) */
804 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
805 (sizeof(void*) >= 8 \
806 ? 1 * 1024 * 1024 * 1024 \
812 #define MAP_FAILED ((void *)-1)
815 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
816 #define on_disk_bytes(st) ((st).st_size)
818 #define on_disk_bytes(st) ((st).st_blocks * 512)
821 #ifdef NEEDS_MODE_TRANSLATION
830 #define S_IFMT 0170000
831 #define S_IFREG 0100000
832 #define S_IFDIR 0040000
833 #define S_IFLNK 0120000
834 #define S_IFBLK 0060000
835 #define S_IFCHR 0020000
836 #define S_IFIFO 0010000
837 #define S_IFSOCK 0140000
841 #define stat(path, buf) git_stat(path, buf)
842 int git_stat(const char *, struct stat
*);
846 #define fstat(fd, buf) git_fstat(fd, buf)
847 int git_fstat(int, struct stat
*);
851 #define lstat(path, buf) git_lstat(path, buf)
852 int git_lstat(const char *, struct stat
*);
855 #define DEFAULT_PACKED_GIT_LIMIT \
856 ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
859 #define pread git_pread
860 ssize_t
git_pread(int fd
, void *buf
, size_t count
, off_t offset
);
863 * Forward decl that will remind us if its twin in cache.h changes.
864 * This function is used in compat/pread.c. But we can't include
867 ssize_t
read_in_full(int fd
, void *buf
, size_t count
);
870 #define setenv gitsetenv
871 int gitsetenv(const char *, const char *, int);
875 #define mkdtemp gitmkdtemp
876 char *gitmkdtemp(char *);
880 #define unsetenv gitunsetenv
881 int gitunsetenv(const char *);
885 #define strcasestr gitstrcasestr
886 char *gitstrcasestr(const char *haystack
, const char *needle
);
890 #define strlcpy gitstrlcpy
891 size_t gitstrlcpy(char *, const char *, size_t);
895 #define strtoumax gitstrtoumax
896 uintmax_t gitstrtoumax(const char *, char **, int);
897 #define strtoimax gitstrtoimax
898 intmax_t gitstrtoimax(const char *, char **, int);
902 #define hstrerror githstrerror
903 const char *githstrerror(int herror
);
907 #define memmem gitmemmem
908 void *gitmemmem(const void *haystack
, size_t haystacklen
,
909 const void *needle
, size_t needlelen
);
912 #ifdef OVERRIDE_STRDUP
916 #define strdup gitstrdup
917 char *gitstrdup(const char *s
);
920 #ifdef NO_GETPAGESIZE
921 #define getpagesize() sysconf(_SC_PAGESIZE)
928 #ifdef FREAD_READS_DIRECTORIES
929 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
933 # define fopen(a,b) git_fopen(a,b)
935 FILE *git_fopen(const char*, const char*);
938 #ifdef SNPRINTF_RETURNS_BOGUS
942 #define snprintf git_snprintf
943 int git_snprintf(char *str
, size_t maxsize
,
944 const char *format
, ...);
948 #define vsnprintf git_vsnprintf
949 int git_vsnprintf(char *str
, size_t maxsize
,
950 const char *format
, va_list ap
);
953 #ifdef OPEN_RETURNS_EINTR
955 #define open git_open_with_retry
956 int git_open_with_retry(const char *path
, int flag
, ...);
959 #ifdef __GLIBC_PREREQ
960 #if __GLIBC_PREREQ(2, 1)
961 #define HAVE_STRCHRNUL
965 #ifndef HAVE_STRCHRNUL
966 #define strchrnul gitstrchrnul
967 static inline char *gitstrchrnul(const char *s
, int c
)
969 while (*s
&& *s
!= c
)
976 int inet_pton(int af
, const char *src
, void *dst
);
980 const char *inet_ntop(int af
, const void *src
, char *dst
, size_t size
);
984 #define atexit git_atexit
985 int git_atexit(void (*handler
)(void));
988 static inline size_t st_add(size_t a
, size_t b
)
990 if (unsigned_add_overflows(a
, b
))
991 die("size_t overflow: %"PRIuMAX
" + %"PRIuMAX
,
992 (uintmax_t)a
, (uintmax_t)b
);
995 #define st_add3(a,b,c) st_add(st_add((a),(b)),(c))
996 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
998 static inline size_t st_mult(size_t a
, size_t b
)
1000 if (unsigned_mult_overflows(a
, b
))
1001 die("size_t overflow: %"PRIuMAX
" * %"PRIuMAX
,
1002 (uintmax_t)a
, (uintmax_t)b
);
1006 static inline size_t st_sub(size_t a
, size_t b
)
1009 die("size_t underflow: %"PRIuMAX
" - %"PRIuMAX
,
1010 (uintmax_t)a
, (uintmax_t)b
);
1014 static inline size_t st_left_shift(size_t a
, unsigned shift
)
1016 if (unsigned_left_shift_overflows(a
, shift
))
1017 die("size_t overflow: %"PRIuMAX
" << %u",
1018 (uintmax_t)a
, shift
);
1022 static inline unsigned long cast_size_t_to_ulong(size_t a
)
1024 if (a
!= (unsigned long)a
)
1025 die("object too large to read on this platform: %"
1026 PRIuMAX
" is cut off to %lu",
1027 (uintmax_t)a
, (unsigned long)a
);
1028 return (unsigned long)a
;
1031 static inline int cast_size_t_to_int(size_t a
)
1034 die("number too large to represent as int on this platform: %"PRIuMAX
,
1040 * Limit size of IO chunks, because huge chunks only cause pain. OS X
1041 * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
1042 * the absence of bugs, large chunks can result in bad latencies when
1043 * you decide to kill the process.
1045 * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
1046 * that is smaller than that, clip it to SSIZE_MAX, as a call to
1047 * read(2) or write(2) larger than that is allowed to fail. As the last
1048 * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
1049 * to override this, if the definition of SSIZE_MAX given by the platform
1053 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
1054 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
1055 # define MAX_IO_SIZE SSIZE_MAX
1057 # define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
1061 #ifdef HAVE_ALLOCA_H
1062 # include <alloca.h>
1063 # define xalloca(size) (alloca(size))
1064 # define xalloca_free(p) do {} while (0)
1066 # define xalloca(size) (xmalloc(size))
1067 # define xalloca_free(p) (free(p))
1069 char *xstrdup(const char *str
);
1070 void *xmalloc(size_t size
);
1071 void *xmallocz(size_t size
);
1072 void *xmallocz_gently(size_t size
);
1073 void *xmemdupz(const void *data
, size_t len
);
1074 char *xstrndup(const char *str
, size_t len
);
1075 void *xrealloc(void *ptr
, size_t size
);
1076 void *xcalloc(size_t nmemb
, size_t size
);
1077 void xsetenv(const char *name
, const char *value
, int overwrite
);
1078 void *xmmap(void *start
, size_t length
, int prot
, int flags
, int fd
, off_t offset
);
1079 const char *mmap_os_err(void);
1080 void *xmmap_gently(void *start
, size_t length
, int prot
, int flags
, int fd
, off_t offset
);
1081 int xopen(const char *path
, int flags
, ...);
1082 ssize_t
xread(int fd
, void *buf
, size_t len
);
1083 ssize_t
xwrite(int fd
, const void *buf
, size_t len
);
1084 ssize_t
xpread(int fd
, void *buf
, size_t len
, off_t offset
);
1086 FILE *xfopen(const char *path
, const char *mode
);
1087 FILE *xfdopen(int fd
, const char *mode
);
1088 int xmkstemp(char *temp_filename
);
1089 int xmkstemp_mode(char *temp_filename
, int mode
);
1090 char *xgetcwd(void);
1091 FILE *fopen_for_writing(const char *path
);
1092 FILE *fopen_or_warn(const char *path
, const char *mode
);
1095 * Like strncmp, but only return zero if s is NUL-terminated and exactly len
1096 * characters long. If it is not, consider it greater than t.
1098 int xstrncmpz(const char *s
, const char *t
, size_t len
);
1101 * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
1102 * that ptr is used twice, so don't pass e.g. ptr++.
1104 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
1106 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
1107 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
1108 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
1110 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
1111 BARF_UNLESS_COPYABLE((dst), (src)))
1112 static inline void copy_array(void *dst
, const void *src
, size_t n
, size_t size
)
1115 memcpy(dst
, src
, st_mult(size
, n
));
1118 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
1119 BARF_UNLESS_COPYABLE((dst), (src)))
1120 static inline void move_array(void *dst
, const void *src
, size_t n
, size_t size
)
1123 memmove(dst
, src
, st_mult(size
, n
));
1126 #define DUP_ARRAY(dst, src, n) do { \
1127 size_t dup_array_n_ = (n); \
1128 COPY_ARRAY(ALLOC_ARRAY((dst), dup_array_n_), (src), dup_array_n_); \
1132 * These functions help you allocate structs with flex arrays, and copy
1133 * the data directly into the array. For example, if you had:
1137 * char name[FLEX_ARRAY];
1143 * FLEX_ALLOC_MEM(f, name, src, len);
1145 * to allocate a "foo" with the contents of "src" in the "name" field.
1146 * The resulting struct is automatically zero'd, and the flex-array field
1147 * is NUL-terminated (whether the incoming src buffer was or not).
1149 * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1150 * but do want to store a pointer to some extra data in the same allocated
1151 * block. For example, if you have:
1161 * FLEXPTR_ALLOC_STR(f, name, src);
1163 * and "name" will point to a block of memory after the struct, which will be
1164 * freed along with the struct (but the pointer can be repointed anywhere).
1166 * The *_STR variants accept a string parameter rather than a ptr/len
1169 * Note that these macros will evaluate the first parameter multiple
1170 * times, and it must be assignable as an lvalue.
1172 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1173 size_t flex_array_len_ = (len); \
1174 (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1175 memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1177 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1178 size_t flex_array_len_ = (len); \
1179 (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1180 memcpy((x) + 1, (buf), flex_array_len_); \
1181 (x)->ptrname = (void *)((x)+1); \
1183 #define FLEX_ALLOC_STR(x, flexname, str) \
1184 FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1185 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1186 FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1188 static inline char *xstrdup_or_null(const char *str
)
1190 return str
? xstrdup(str
) : NULL
;
1193 static inline size_t xsize_t(off_t len
)
1195 if (len
< 0 || (uintmax_t) len
> SIZE_MAX
)
1196 die("Cannot handle files this big");
1197 return (size_t) len
;
1200 __attribute__((format (printf
, 3, 4)))
1201 int xsnprintf(char *dst
, size_t max
, const char *fmt
, ...);
1203 #ifndef HOST_NAME_MAX
1204 #define HOST_NAME_MAX 256
1207 int xgethostname(char *buf
, size_t len
);
1209 /* in ctype.c, for kwset users */
1210 extern const unsigned char tolower_trans_tbl
[256];
1212 /* Sane ctype - no locale, and works with signed chars */
1227 extern const unsigned char sane_ctype
[256];
1228 extern const signed char hexval_table
[256];
1229 #define GIT_SPACE 0x01
1230 #define GIT_DIGIT 0x02
1231 #define GIT_ALPHA 0x04
1232 #define GIT_GLOB_SPECIAL 0x08
1233 #define GIT_REGEX_SPECIAL 0x10
1234 #define GIT_PATHSPEC_MAGIC 0x20
1235 #define GIT_CNTRL 0x40
1236 #define GIT_PUNCT 0x80
1237 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1238 #define isascii(x) (((x) & ~0x7f) == 0)
1239 #define isspace(x) sane_istest(x,GIT_SPACE)
1240 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1241 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1242 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1243 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1244 #define islower(x) sane_iscase(x, 1)
1245 #define isupper(x) sane_iscase(x, 0)
1246 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1247 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1248 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1249 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1250 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1251 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1252 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1253 #define toupper(x) sane_case((unsigned char)(x), 0)
1254 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1256 static inline int sane_case(int x
, int high
)
1258 if (sane_istest(x
, GIT_ALPHA
))
1259 x
= (x
& ~0x20) | high
;
1263 static inline int sane_iscase(int x
, int is_lower
)
1265 if (!sane_istest(x
, GIT_ALPHA
))
1269 return (x
& 0x20) != 0;
1271 return (x
& 0x20) == 0;
1275 * Like skip_prefix, but compare case-insensitively. Note that the comparison
1276 * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1277 * locale-specific conversions).
1279 static inline int skip_iprefix(const char *str
, const char *prefix
,
1287 } while (tolower(*str
++) == tolower(*prefix
++));
1291 static inline int strtoul_ui(char const *s
, int base
, unsigned int *result
)
1297 /* negative values would be accepted by strtoul */
1300 ul
= strtoul(s
, &p
, base
);
1301 if (errno
|| *p
|| p
== s
|| (unsigned int) ul
!= ul
)
1307 static inline int strtol_i(char const *s
, int base
, int *result
)
1313 ul
= strtol(s
, &p
, base
);
1314 if (errno
|| *p
|| p
== s
|| (int) ul
!= ul
)
1320 void git_stable_qsort(void *base
, size_t nmemb
, size_t size
,
1321 int(*compar
)(const void *, const void *));
1322 #ifdef INTERNAL_QSORT
1323 #define qsort git_stable_qsort
1326 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1327 static inline void sane_qsort(void *base
, size_t nmemb
, size_t size
,
1328 int(*compar
)(const void *, const void *))
1331 qsort(base
, nmemb
, size
, compar
);
1334 #define STABLE_QSORT(base, n, compar) \
1335 git_stable_qsort((base), (n), sizeof(*(base)), compar)
1337 #ifndef HAVE_ISO_QSORT_S
1338 int git_qsort_s(void *base
, size_t nmemb
, size_t size
,
1339 int (*compar
)(const void *, const void *, void *), void *ctx
);
1340 #define qsort_s git_qsort_s
1343 #define QSORT_S(base, n, compar, ctx) do { \
1344 if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1345 BUG("qsort_s() failed"); \
1348 #ifndef REG_STARTEND
1349 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1352 static inline int regexec_buf(const regex_t
*preg
, const char *buf
, size_t size
,
1353 size_t nmatch
, regmatch_t pmatch
[], int eflags
)
1355 assert(nmatch
> 0 && pmatch
);
1356 pmatch
[0].rm_so
= 0;
1357 pmatch
[0].rm_eo
= size
;
1358 return regexec(preg
, buf
, nmatch
, pmatch
, eflags
| REG_STARTEND
);
1361 #ifdef USE_ENHANCED_BASIC_REGULAR_EXPRESSIONS
1362 int git_regcomp(regex_t
*preg
, const char *pattern
, int cflags
);
1363 #define regcomp git_regcomp
1366 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1367 # define FORCE_DIR_SET_GID S_ISGID
1369 # define FORCE_DIR_SET_GID 0
1374 #define ST_CTIME_NSEC(st) 0
1375 #define ST_MTIME_NSEC(st) 0
1377 #ifdef USE_ST_TIMESPEC
1378 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1379 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1381 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1382 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1386 #ifdef UNRELIABLE_FSTAT
1387 #define fstat_is_reliable() 0
1389 #define fstat_is_reliable() 1
1394 * Since an obvious implementation of va_list would be to make it a
1395 * pointer into the stack frame, a simple assignment will work on
1396 * many systems. But let's try to be more portable.
1399 #define va_copy(dst, src) __va_copy(dst, src)
1401 #define va_copy(dst, src) ((dst) = (src))
1405 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1406 extern int BUG_exit_code
;
1408 /* usage.c: if bug() is called we should have a BUG_if_bug() afterwards */
1409 extern int bug_called_must_BUG
;
1411 __attribute__((format (printf
, 3, 4))) NORETURN
1412 void BUG_fl(const char *file
, int line
, const char *fmt
, ...);
1413 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1414 __attribute__((format (printf
, 3, 4)))
1415 void bug_fl(const char *file
, int line
, const char *fmt
, ...);
1416 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)
1417 #define BUG_if_bug(...) do { \
1418 if (bug_called_must_BUG) \
1419 BUG_fl(__FILE__, __LINE__, __VA_ARGS__); \
1422 #ifndef FSYNC_METHOD_DEFAULT
1424 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_WRITEOUT_ONLY
1426 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_FSYNC
1431 FSYNC_WRITEOUT_ONLY
,
1432 FSYNC_HARDWARE_FLUSH
1436 * Issues an fsync against the specified file according to the specified mode.
1438 * FSYNC_WRITEOUT_ONLY attempts to use interfaces available on some operating
1439 * systems to flush the OS cache without issuing a flush command to the storage
1440 * controller. If those interfaces are unavailable, the function fails with
1443 * FSYNC_HARDWARE_FLUSH does an OS writeout and hardware flush to ensure that
1444 * changes are durable. It is not expected to fail.
1446 int git_fsync(int fd
, enum fsync_action action
);
1449 * Writes out trace statistics for fsync using the trace2 API.
1451 void trace_git_fsync_stats(void);
1454 * Preserves errno, prints a message, but gives no warning for ENOENT.
1455 * Returns 0 on success, which includes trying to unlink an object that does
1458 int unlink_or_warn(const char *path
);
1460 * Tries to unlink file. Returns 0 if unlink succeeded
1461 * or the file already didn't exist. Returns -1 and
1462 * appends a message to err suitable for
1463 * 'error("%s", err->buf)' on error.
1465 int unlink_or_msg(const char *file
, struct strbuf
*err
);
1467 * Preserves errno, prints a message, but gives no warning for ENOENT.
1468 * Returns 0 on success, which includes trying to remove a directory that does
1471 int rmdir_or_warn(const char *path
);
1473 * Calls the correct function out of {unlink,rmdir}_or_warn based on
1474 * the supplied file mode.
1476 int remove_or_warn(unsigned int mode
, const char *path
);
1479 * Call access(2), but warn for any error except "missing file"
1480 * (ENOENT or ENOTDIR).
1482 #define ACCESS_EACCES_OK (1U << 0)
1483 int access_or_warn(const char *path
, int mode
, unsigned flag
);
1484 int access_or_die(const char *path
, int mode
, unsigned flag
);
1486 /* Warn on an inaccessible file if errno indicates this is an error */
1487 int warn_on_fopen_errors(const char *path
);
1490 * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1491 * may be racy. Do not use this as protection against an attacker who can
1492 * simultaneously create paths.
1494 int open_nofollow(const char *path
, int flags
);
1497 # define SHELL_PATH "/bin/sh"
1500 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1501 static inline void git_flockfile(FILE *fh UNUSED
)
1505 static inline void git_funlockfile(FILE *fh UNUSED
)
1511 #undef getc_unlocked
1512 #define flockfile(fh) git_flockfile(fh)
1513 #define funlockfile(fh) git_funlockfile(fh)
1514 #define getc_unlocked(fh) getc(fh)
1517 #ifdef FILENO_IS_A_MACRO
1518 int git_fileno(FILE *stream
);
1519 # ifndef COMPAT_CODE_FILENO
1521 # define fileno(p) git_fileno(p)
1525 #ifdef NEED_ACCESS_ROOT_HANDLER
1526 int git_access(const char *path
, int mode
);
1527 # ifndef COMPAT_CODE_ACCESS
1531 # define access(path, mode) git_access(path, mode)
1536 * Our code often opens a path to an optional file, to work on its
1537 * contents when we can successfully open it. We can ignore a failure
1538 * to open if such an optional file does not exist, but we do want to
1539 * report a failure in opening for other reasons (e.g. we got an I/O
1540 * error, or the file is there, but we lack the permission to open).
1542 * Call this function after seeing an error from open() or fopen() to
1543 * see if the errno indicates a missing file that we can safely ignore.
1545 static inline int is_missing_file_error(int errno_
)
1547 return (errno_
== ENOENT
|| errno_
== ENOTDIR
);
1550 int cmd_main(int, const char **);
1553 * Intercept all calls to exit() and route them to trace2 to
1554 * optionally emit a message before calling the real exit().
1556 int common_exit(const char *file
, int line
, int code
);
1557 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
1560 * You can mark a stack variable with UNLEAK(var) to avoid it being
1561 * reported as a leak by tools like LSAN or valgrind. The argument
1562 * should generally be the variable itself (not its address and not what
1563 * it points to). It's safe to use this on pointers which may already
1564 * have been freed, or on pointers which may still be in use.
1566 * Use this _only_ for a variable that leaks by going out of scope at
1567 * program exit (so only from cmd_* functions or their direct helpers).
1568 * Normal functions, especially those which may be called multiple
1569 * times, should actually free their memory. This is only meant as
1570 * an annotation, and does nothing in non-leak-checking builds.
1572 #ifdef SUPPRESS_ANNOTATED_LEAKS
1573 void unleak_memory(const void *ptr
, size_t len
);
1574 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1576 #define UNLEAK(var) do {} while (0)
1582 #if ZLIB_VERNUM < 0x1290
1584 * This is uncompress2, which is only available in zlib >= 1.2.9
1585 * (released as of early 2017). See compat/zlib-uncompress2.c.
1587 int uncompress2(Bytef
*dest
, uLongf
*destLen
, const Bytef
*source
,
1592 * This include must come after system headers, since it introduces macros that
1593 * replace system names.
1598 * container_of - Get the address of an object containing a field.
1600 * @ptr: pointer to the field.
1601 * @type: type of the object.
1602 * @member: name of the field within the object.
1604 #define container_of(ptr, type, member) \
1605 ((type *) ((char *)(ptr) - offsetof(type, member)))
1608 * helper function for `container_of_or_null' to avoid multiple
1609 * evaluation of @ptr
1611 static inline void *container_of_or_null_offset(void *ptr
, size_t offset
)
1613 return ptr
? (char *)ptr
- offset
: NULL
;
1617 * like `container_of', but allows returned value to be NULL
1619 #define container_of_or_null(ptr, type, member) \
1620 (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1623 * like offsetof(), but takes a pointer to a variable of type which
1624 * contains @member, instead of a specified type.
1625 * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1628 #if defined(__GNUC__) /* clang sets this, too */
1629 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1630 #else /* !__GNUC__ */
1631 #define OFFSETOF_VAR(ptr, member) \
1632 ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1633 #endif /* !__GNUC__ */
1635 void sleep_millisec(int millisec
);
1638 * Generate len bytes from the system cryptographically secure PRNG.
1639 * Returns 0 on success and -1 on error, setting errno. The inability to
1640 * satisfy the full request is an error.
1642 int csprng_bytes(void *buf
, size_t len
);