notes-merge: use O_EXCL to avoid overwriting existing files
[git/git-svn.git] / git-compat-util.h
blob1f8b5f3b1f1ac17716681fee2d72b9c124a9b99c
1 #ifndef GIT_COMPAT_UTIL_H
2 #define GIT_COMPAT_UTIL_H
4 #define _FILE_OFFSET_BITS 64
7 /* Derived from Linux "Features Test Macro" header
8 * Convenience macros to test the versions of gcc (or
9 * a compatible compiler).
10 * Use them like this:
11 * #if GIT_GNUC_PREREQ (2,8)
12 * ... code requiring gcc 2.8 or later ...
13 * #endif
15 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
16 # define GIT_GNUC_PREREQ(maj, min) \
17 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
18 #else
19 #define GIT_GNUC_PREREQ(maj, min) 0
20 #endif
23 #ifndef FLEX_ARRAY
25 * See if our compiler is known to support flexible array members.
27 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && (!defined(__SUNPRO_C) || (__SUNPRO_C > 0x580))
28 # define FLEX_ARRAY /* empty */
29 #elif defined(__GNUC__)
30 # if (__GNUC__ >= 3)
31 # define FLEX_ARRAY /* empty */
32 # else
33 # define FLEX_ARRAY 0 /* older GNU extension */
34 # endif
35 #endif
38 * Otherwise, default to safer but a bit wasteful traditional style
40 #ifndef FLEX_ARRAY
41 # define FLEX_ARRAY 1
42 #endif
43 #endif
47 * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
48 * @cond: the compile-time condition which must be true.
50 * Your compile will fail if the condition isn't true, or can't be evaluated
51 * by the compiler. This can be used in an expression: its value is "0".
53 * Example:
54 * #define foo_to_char(foo) \
55 * ((char *)(foo) \
56 * + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
58 #define BUILD_ASSERT_OR_ZERO(cond) \
59 (sizeof(char [1 - 2*!(cond)]) - 1)
61 #if GIT_GNUC_PREREQ(3, 1)
62 /* &arr[0] degrades to a pointer: a different type from an array */
63 # define BARF_UNLESS_AN_ARRAY(arr) \
64 BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
65 __typeof__(&(arr)[0])))
66 #else
67 # define BARF_UNLESS_AN_ARRAY(arr) 0
68 #endif
70 * ARRAY_SIZE - get the number of elements in a visible array
71 * <at> x: the array whose size you want.
73 * This does not work on pointers, or arrays declared as [], or
74 * function parameters. With correct compiler support, such usage
75 * will cause a build error (see the build_assert_or_zero macro).
77 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
79 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
81 #define maximum_signed_value_of_type(a) \
82 (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
84 #define maximum_unsigned_value_of_type(a) \
85 (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
88 * Signed integer overflow is undefined in C, so here's a helper macro
89 * to detect if the sum of two integers will overflow.
91 * Requires: a >= 0, typeof(a) equals typeof(b)
93 #define signed_add_overflows(a, b) \
94 ((b) > maximum_signed_value_of_type(a) - (a))
96 #define unsigned_add_overflows(a, b) \
97 ((b) > maximum_unsigned_value_of_type(a) - (a))
100 * Returns true if the multiplication of "a" and "b" will
101 * overflow. The types of "a" and "b" must match and must be unsigned.
102 * Note that this macro evaluates "a" twice!
104 #define unsigned_mult_overflows(a, b) \
105 ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
107 #ifdef __GNUC__
108 #define TYPEOF(x) (__typeof__(x))
109 #else
110 #define TYPEOF(x)
111 #endif
113 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
114 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
116 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
118 /* Approximation of the length of the decimal representation of this type. */
119 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
121 #if defined(__sun__)
123 * On Solaris, when _XOPEN_EXTENDED is set, its header file
124 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
125 * setting to say we are XPG5 or XPG6. Also on Solaris,
126 * XPG6 programs must be compiled with a c99 compiler, while
127 * non XPG6 programs must be compiled with a pre-c99 compiler.
129 # if __STDC_VERSION__ - 0 >= 199901L
130 # define _XOPEN_SOURCE 600
131 # else
132 # define _XOPEN_SOURCE 500
133 # endif
134 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
135 !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
136 !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
137 !defined(__CYGWIN__)
138 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
139 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
140 #endif
141 #define _ALL_SOURCE 1
142 #define _GNU_SOURCE 1
143 #define _BSD_SOURCE 1
144 #define _DEFAULT_SOURCE 1
145 #define _NETBSD_SOURCE 1
146 #define _SGI_SOURCE 1
148 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
149 # if defined (_MSC_VER) && !defined(_WIN32_WINNT)
150 # define _WIN32_WINNT 0x0502
151 # endif
152 #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
153 #include <winsock2.h>
154 #include <windows.h>
155 #define GIT_WINDOWS_NATIVE
156 #endif
158 #include <unistd.h>
159 #include <stdio.h>
160 #include <sys/stat.h>
161 #include <fcntl.h>
162 #include <stddef.h>
163 #include <stdlib.h>
164 #include <stdarg.h>
165 #include <string.h>
166 #ifdef HAVE_STRINGS_H
167 #include <strings.h> /* for strcasecmp() */
168 #endif
169 #include <errno.h>
170 #include <limits.h>
171 #ifdef NEEDS_SYS_PARAM_H
172 #include <sys/param.h>
173 #endif
174 #include <sys/types.h>
175 #include <dirent.h>
176 #include <sys/time.h>
177 #include <time.h>
178 #include <signal.h>
179 #include <assert.h>
180 #include <regex.h>
181 #include <utime.h>
182 #include <syslog.h>
183 #ifndef NO_SYS_POLL_H
184 #include <sys/poll.h>
185 #else
186 #include <poll.h>
187 #endif
188 #ifdef HAVE_BSD_SYSCTL
189 #include <sys/sysctl.h>
190 #endif
192 #if defined(__MINGW32__)
193 /* pull in Windows compatibility stuff */
194 #include "compat/mingw.h"
195 #elif defined(_MSC_VER)
196 #include "compat/msvc.h"
197 #else
198 #include <sys/utsname.h>
199 #include <sys/wait.h>
200 #include <sys/resource.h>
201 #include <sys/socket.h>
202 #include <sys/ioctl.h>
203 #include <termios.h>
204 #ifndef NO_SYS_SELECT_H
205 #include <sys/select.h>
206 #endif
207 #include <netinet/in.h>
208 #include <netinet/tcp.h>
209 #include <arpa/inet.h>
210 #include <netdb.h>
211 #include <pwd.h>
212 #include <sys/un.h>
213 #ifndef NO_INTTYPES_H
214 #include <inttypes.h>
215 #else
216 #include <stdint.h>
217 #endif
218 #ifdef NO_INTPTR_T
220 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
221 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
222 * while on IP16 and IP16L32 it is "int" (resp. "short")
223 * Size needs to match (or exceed) 'sizeof(void *)'.
224 * We can't take "long long" here as not everybody has it.
226 typedef long intptr_t;
227 typedef unsigned long uintptr_t;
228 #endif
229 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
230 #include <grp.h>
231 #define _ALL_SOURCE 1
232 #endif
234 /* used on Mac OS X */
235 #ifdef PRECOMPOSE_UNICODE
236 #include "compat/precompose_utf8.h"
237 #else
238 #define precompose_str(in,i_nfd2nfc)
239 #define precompose_argv(c,v)
240 #define probe_utf8_pathname_composition()
241 #endif
243 #ifdef MKDIR_WO_TRAILING_SLASH
244 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
245 extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
246 #endif
248 #ifdef NO_STRUCT_ITIMERVAL
249 struct itimerval {
250 struct timeval it_interval;
251 struct timeval it_value;
253 #endif
255 #ifdef NO_SETITIMER
256 #define setitimer(which,value,ovalue)
257 #endif
259 #ifndef NO_LIBGEN_H
260 #include <libgen.h>
261 #else
262 #define basename gitbasename
263 extern char *gitbasename(char *);
264 #define dirname gitdirname
265 extern char *gitdirname(char *);
266 #endif
268 #ifndef NO_ICONV
269 #include <iconv.h>
270 #endif
272 #ifndef NO_OPENSSL
273 #ifdef __APPLE__
274 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
275 #include <AvailabilityMacros.h>
276 #undef DEPRECATED_ATTRIBUTE
277 #define DEPRECATED_ATTRIBUTE
278 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
279 #endif
280 #include <openssl/ssl.h>
281 #include <openssl/err.h>
282 #endif
284 /* On most systems <netdb.h> would have given us this, but
285 * not on some systems (e.g. z/OS).
287 #ifndef NI_MAXHOST
288 #define NI_MAXHOST 1025
289 #endif
291 #ifndef NI_MAXSERV
292 #define NI_MAXSERV 32
293 #endif
295 /* On most systems <limits.h> would have given us this, but
296 * not on some systems (e.g. GNU/Hurd).
298 #ifndef PATH_MAX
299 #define PATH_MAX 4096
300 #endif
302 #ifndef PRIuMAX
303 #define PRIuMAX "llu"
304 #endif
306 #ifndef SCNuMAX
307 #define SCNuMAX PRIuMAX
308 #endif
310 #ifndef PRIu32
311 #define PRIu32 "u"
312 #endif
314 #ifndef PRIx32
315 #define PRIx32 "x"
316 #endif
318 #ifndef PRIo32
319 #define PRIo32 "o"
320 #endif
322 #ifndef PATH_SEP
323 #define PATH_SEP ':'
324 #endif
326 #ifdef HAVE_PATHS_H
327 #include <paths.h>
328 #endif
329 #ifndef _PATH_DEFPATH
330 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
331 #endif
333 #ifndef has_dos_drive_prefix
334 static inline int git_has_dos_drive_prefix(const char *path)
336 return 0;
338 #define has_dos_drive_prefix git_has_dos_drive_prefix
339 #endif
341 #ifndef skip_dos_drive_prefix
342 static inline int git_skip_dos_drive_prefix(char **path)
344 return 0;
346 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
347 #endif
349 #ifndef is_dir_sep
350 static inline int git_is_dir_sep(int c)
352 return c == '/';
354 #define is_dir_sep git_is_dir_sep
355 #endif
357 #ifndef offset_1st_component
358 static inline int git_offset_1st_component(const char *path)
360 return is_dir_sep(path[0]);
362 #define offset_1st_component git_offset_1st_component
363 #endif
365 #ifndef find_last_dir_sep
366 static inline char *git_find_last_dir_sep(const char *path)
368 return strrchr(path, '/');
370 #define find_last_dir_sep git_find_last_dir_sep
371 #endif
373 #if defined(__HP_cc) && (__HP_cc >= 61000)
374 #define NORETURN __attribute__((noreturn))
375 #define NORETURN_PTR
376 #elif defined(__GNUC__) && !defined(NO_NORETURN)
377 #define NORETURN __attribute__((__noreturn__))
378 #define NORETURN_PTR __attribute__((__noreturn__))
379 #elif defined(_MSC_VER)
380 #define NORETURN __declspec(noreturn)
381 #define NORETURN_PTR
382 #else
383 #define NORETURN
384 #define NORETURN_PTR
385 #ifndef __GNUC__
386 #ifndef __attribute__
387 #define __attribute__(x)
388 #endif
389 #endif
390 #endif
392 /* The sentinel attribute is valid from gcc version 4.0 */
393 #if defined(__GNUC__) && (__GNUC__ >= 4)
394 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
395 #else
396 #define LAST_ARG_MUST_BE_NULL
397 #endif
399 #include "compat/bswap.h"
401 #include "wildmatch.h"
403 struct strbuf;
405 /* General helper functions */
406 extern void vreportf(const char *prefix, const char *err, va_list params);
407 extern NORETURN void usage(const char *err);
408 extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
409 extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
410 extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
411 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
412 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
414 #ifndef NO_OPENSSL
415 #ifdef APPLE_COMMON_CRYPTO
416 #include "compat/apple-common-crypto.h"
417 #else
418 #include <openssl/evp.h>
419 #include <openssl/hmac.h>
420 #endif /* APPLE_COMMON_CRYPTO */
421 #include <openssl/x509v3.h>
422 #endif /* NO_OPENSSL */
425 * Let callers be aware of the constant return value; this can help
426 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
427 * because some compilers may not support variadic macros. Since we're only
428 * trying to help gcc, anyway, it's OK; other compilers will fall back to
429 * using the function as usual.
431 #if defined(__GNUC__)
432 static inline int const_error(void)
434 return -1;
436 #define error(...) (error(__VA_ARGS__), const_error())
437 #endif
439 extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
440 extern void set_error_routine(void (*routine)(const char *err, va_list params));
441 extern void set_die_is_recursing_routine(int (*routine)(void));
442 extern void set_error_handle(FILE *);
444 extern int starts_with(const char *str, const char *prefix);
447 * If the string "str" begins with the string found in "prefix", return 1.
448 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
449 * the string right after the prefix).
451 * Otherwise, return 0 and leave "out" untouched.
453 * Examples:
455 * [extract branch name, fail if not a branch]
456 * if (!skip_prefix(ref, "refs/heads/", &branch)
457 * return -1;
459 * [skip prefix if present, otherwise use whole string]
460 * skip_prefix(name, "refs/heads/", &name);
462 static inline int skip_prefix(const char *str, const char *prefix,
463 const char **out)
465 do {
466 if (!*prefix) {
467 *out = str;
468 return 1;
470 } while (*str++ == *prefix++);
471 return 0;
475 * If buf ends with suffix, return 1 and subtract the length of the suffix
476 * from *len. Otherwise, return 0 and leave *len untouched.
478 static inline int strip_suffix_mem(const char *buf, size_t *len,
479 const char *suffix)
481 size_t suflen = strlen(suffix);
482 if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
483 return 0;
484 *len -= suflen;
485 return 1;
489 * If str ends with suffix, return 1 and set *len to the size of the string
490 * without the suffix. Otherwise, return 0 and set *len to the size of the
491 * string.
493 * Note that we do _not_ NUL-terminate str to the new length.
495 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
497 *len = strlen(str);
498 return strip_suffix_mem(str, len, suffix);
501 static inline int ends_with(const char *str, const char *suffix)
503 size_t len;
504 return strip_suffix(str, suffix, &len);
507 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
509 #ifndef PROT_READ
510 #define PROT_READ 1
511 #define PROT_WRITE 2
512 #define MAP_PRIVATE 1
513 #endif
515 #define mmap git_mmap
516 #define munmap git_munmap
517 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
518 extern int git_munmap(void *start, size_t length);
520 #else /* NO_MMAP || USE_WIN32_MMAP */
522 #include <sys/mman.h>
524 #endif /* NO_MMAP || USE_WIN32_MMAP */
526 #ifdef NO_MMAP
528 /* This value must be multiple of (pagesize * 2) */
529 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
531 #else /* NO_MMAP */
533 /* This value must be multiple of (pagesize * 2) */
534 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
535 (sizeof(void*) >= 8 \
536 ? 1 * 1024 * 1024 * 1024 \
537 : 32 * 1024 * 1024)
539 #endif /* NO_MMAP */
541 #ifndef MAP_FAILED
542 #define MAP_FAILED ((void *)-1)
543 #endif
545 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
546 #define on_disk_bytes(st) ((st).st_size)
547 #else
548 #define on_disk_bytes(st) ((st).st_blocks * 512)
549 #endif
551 #ifdef NEEDS_MODE_TRANSLATION
552 #undef S_IFMT
553 #undef S_IFREG
554 #undef S_IFDIR
555 #undef S_IFLNK
556 #undef S_IFBLK
557 #undef S_IFCHR
558 #undef S_IFIFO
559 #undef S_IFSOCK
560 #define S_IFMT 0170000
561 #define S_IFREG 0100000
562 #define S_IFDIR 0040000
563 #define S_IFLNK 0120000
564 #define S_IFBLK 0060000
565 #define S_IFCHR 0020000
566 #define S_IFIFO 0010000
567 #define S_IFSOCK 0140000
568 #ifdef stat
569 #undef stat
570 #endif
571 #define stat(path, buf) git_stat(path, buf)
572 extern int git_stat(const char *, struct stat *);
573 #ifdef fstat
574 #undef fstat
575 #endif
576 #define fstat(fd, buf) git_fstat(fd, buf)
577 extern int git_fstat(int, struct stat *);
578 #ifdef lstat
579 #undef lstat
580 #endif
581 #define lstat(path, buf) git_lstat(path, buf)
582 extern int git_lstat(const char *, struct stat *);
583 #endif
585 #define DEFAULT_PACKED_GIT_LIMIT \
586 ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? 8192 : 256))
588 #ifdef NO_PREAD
589 #define pread git_pread
590 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
591 #endif
593 * Forward decl that will remind us if its twin in cache.h changes.
594 * This function is used in compat/pread.c. But we can't include
595 * cache.h there.
597 extern ssize_t read_in_full(int fd, void *buf, size_t count);
599 #ifdef NO_SETENV
600 #define setenv gitsetenv
601 extern int gitsetenv(const char *, const char *, int);
602 #endif
604 #ifdef NO_MKDTEMP
605 #define mkdtemp gitmkdtemp
606 extern char *gitmkdtemp(char *);
607 #endif
609 #ifdef NO_MKSTEMPS
610 #define mkstemps gitmkstemps
611 extern int gitmkstemps(char *, int);
612 #endif
614 #ifdef NO_UNSETENV
615 #define unsetenv gitunsetenv
616 extern void gitunsetenv(const char *);
617 #endif
619 #ifdef NO_STRCASESTR
620 #define strcasestr gitstrcasestr
621 extern char *gitstrcasestr(const char *haystack, const char *needle);
622 #endif
624 #ifdef NO_STRLCPY
625 #define strlcpy gitstrlcpy
626 extern size_t gitstrlcpy(char *, const char *, size_t);
627 #endif
629 #ifdef NO_STRTOUMAX
630 #define strtoumax gitstrtoumax
631 extern uintmax_t gitstrtoumax(const char *, char **, int);
632 #define strtoimax gitstrtoimax
633 extern intmax_t gitstrtoimax(const char *, char **, int);
634 #endif
636 #ifdef NO_HSTRERROR
637 #define hstrerror githstrerror
638 extern const char *githstrerror(int herror);
639 #endif
641 #ifdef NO_MEMMEM
642 #define memmem gitmemmem
643 void *gitmemmem(const void *haystack, size_t haystacklen,
644 const void *needle, size_t needlelen);
645 #endif
647 #ifdef NO_GETPAGESIZE
648 #define getpagesize() sysconf(_SC_PAGESIZE)
649 #endif
651 #ifdef FREAD_READS_DIRECTORIES
652 #ifdef fopen
653 #undef fopen
654 #endif
655 #define fopen(a,b) git_fopen(a,b)
656 extern FILE *git_fopen(const char*, const char*);
657 #endif
659 #ifdef SNPRINTF_RETURNS_BOGUS
660 #ifdef snprintf
661 #undef snprintf
662 #endif
663 #define snprintf git_snprintf
664 extern int git_snprintf(char *str, size_t maxsize,
665 const char *format, ...);
666 #ifdef vsnprintf
667 #undef vsnprintf
668 #endif
669 #define vsnprintf git_vsnprintf
670 extern int git_vsnprintf(char *str, size_t maxsize,
671 const char *format, va_list ap);
672 #endif
674 #ifdef __GLIBC_PREREQ
675 #if __GLIBC_PREREQ(2, 1)
676 #define HAVE_STRCHRNUL
677 #endif
678 #endif
680 #ifndef HAVE_STRCHRNUL
681 #define strchrnul gitstrchrnul
682 static inline char *gitstrchrnul(const char *s, int c)
684 while (*s && *s != c)
685 s++;
686 return (char *)s;
688 #endif
690 #ifdef NO_INET_PTON
691 int inet_pton(int af, const char *src, void *dst);
692 #endif
694 #ifdef NO_INET_NTOP
695 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
696 #endif
698 #ifdef NO_PTHREADS
699 #define atexit git_atexit
700 extern int git_atexit(void (*handler)(void));
701 #endif
703 extern void release_pack_memory(size_t);
705 typedef void (*try_to_free_t)(size_t);
706 extern try_to_free_t set_try_to_free_routine(try_to_free_t);
708 static inline size_t st_add(size_t a, size_t b)
710 if (unsigned_add_overflows(a, b))
711 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
712 (uintmax_t)a, (uintmax_t)b);
713 return a + b;
715 #define st_add3(a,b,c) st_add(st_add((a),(b)),(c))
716 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
718 static inline size_t st_mult(size_t a, size_t b)
720 if (unsigned_mult_overflows(a, b))
721 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
722 (uintmax_t)a, (uintmax_t)b);
723 return a * b;
726 static inline size_t st_sub(size_t a, size_t b)
728 if (a < b)
729 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
730 (uintmax_t)a, (uintmax_t)b);
731 return a - b;
734 #ifdef HAVE_ALLOCA_H
735 # include <alloca.h>
736 # define xalloca(size) (alloca(size))
737 # define xalloca_free(p) do {} while (0)
738 #else
739 # define xalloca(size) (xmalloc(size))
740 # define xalloca_free(p) (free(p))
741 #endif
742 extern char *xstrdup(const char *str);
743 extern void *xmalloc(size_t size);
744 extern void *xmallocz(size_t size);
745 extern void *xmallocz_gently(size_t size);
746 extern void *xmemdupz(const void *data, size_t len);
747 extern char *xstrndup(const char *str, size_t len);
748 extern void *xrealloc(void *ptr, size_t size);
749 extern void *xcalloc(size_t nmemb, size_t size);
750 extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
751 extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
752 extern int xopen(const char *path, int flags, ...);
753 extern ssize_t xread(int fd, void *buf, size_t len);
754 extern ssize_t xwrite(int fd, const void *buf, size_t len);
755 extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
756 extern int xdup(int fd);
757 extern FILE *xfopen(const char *path, const char *mode);
758 extern FILE *xfdopen(int fd, const char *mode);
759 extern int xmkstemp(char *template);
760 extern int xmkstemp_mode(char *template, int mode);
761 extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
762 extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
763 extern char *xgetcwd(void);
764 extern FILE *fopen_for_writing(const char *path);
766 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
767 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
770 * These functions help you allocate structs with flex arrays, and copy
771 * the data directly into the array. For example, if you had:
773 * struct foo {
774 * int bar;
775 * char name[FLEX_ARRAY];
776 * };
778 * you can do:
780 * struct foo *f;
781 * FLEX_ALLOC_MEM(f, name, src, len);
783 * to allocate a "foo" with the contents of "src" in the "name" field.
784 * The resulting struct is automatically zero'd, and the flex-array field
785 * is NUL-terminated (whether the incoming src buffer was or not).
787 * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
788 * but do want to store a pointer to some extra data in the same allocated
789 * block. For example, if you have:
791 * struct foo {
792 * char *name;
793 * int bar;
794 * };
796 * you can do:
798 * struct foo *f;
799 * FLEX_ALLOC_STR(f, name, src);
801 * and "name" will point to a block of memory after the struct, which will be
802 * freed along with the struct (but the pointer can be repointed anywhere).
804 * The *_STR variants accept a string parameter rather than a ptr/len
805 * combination.
807 * Note that these macros will evaluate the first parameter multiple
808 * times, and it must be assignable as an lvalue.
810 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
811 (x) = NULL; /* silence -Wuninitialized for offset calculation */ \
812 (x) = xalloc_flex(sizeof(*(x)), (char *)(&((x)->flexname)) - (char *)(x), (buf), (len)); \
813 } while (0)
814 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
815 (x) = xalloc_flex(sizeof(*(x)), sizeof(*(x)), (buf), (len)); \
816 (x)->ptrname = (void *)((x)+1); \
817 } while(0)
818 #define FLEX_ALLOC_STR(x, flexname, str) \
819 FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
820 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
821 FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
823 static inline void *xalloc_flex(size_t base_len, size_t offset,
824 const void *src, size_t src_len)
826 unsigned char *ret = xcalloc(1, st_add3(base_len, src_len, 1));
827 memcpy(ret + offset, src, src_len);
828 return ret;
831 static inline char *xstrdup_or_null(const char *str)
833 return str ? xstrdup(str) : NULL;
836 static inline size_t xsize_t(off_t len)
838 if (len > (size_t) len)
839 die("Cannot handle files this big");
840 return (size_t)len;
843 __attribute__((format (printf, 3, 4)))
844 extern int xsnprintf(char *dst, size_t max, const char *fmt, ...);
846 /* in ctype.c, for kwset users */
847 extern const unsigned char tolower_trans_tbl[256];
849 /* Sane ctype - no locale, and works with signed chars */
850 #undef isascii
851 #undef isspace
852 #undef isdigit
853 #undef isalpha
854 #undef isalnum
855 #undef isprint
856 #undef islower
857 #undef isupper
858 #undef tolower
859 #undef toupper
860 #undef iscntrl
861 #undef ispunct
862 #undef isxdigit
864 extern const unsigned char sane_ctype[256];
865 #define GIT_SPACE 0x01
866 #define GIT_DIGIT 0x02
867 #define GIT_ALPHA 0x04
868 #define GIT_GLOB_SPECIAL 0x08
869 #define GIT_REGEX_SPECIAL 0x10
870 #define GIT_PATHSPEC_MAGIC 0x20
871 #define GIT_CNTRL 0x40
872 #define GIT_PUNCT 0x80
873 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
874 #define isascii(x) (((x) & ~0x7f) == 0)
875 #define isspace(x) sane_istest(x,GIT_SPACE)
876 #define isdigit(x) sane_istest(x,GIT_DIGIT)
877 #define isalpha(x) sane_istest(x,GIT_ALPHA)
878 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
879 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
880 #define islower(x) sane_iscase(x, 1)
881 #define isupper(x) sane_iscase(x, 0)
882 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
883 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
884 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
885 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
886 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
887 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
888 #define tolower(x) sane_case((unsigned char)(x), 0x20)
889 #define toupper(x) sane_case((unsigned char)(x), 0)
890 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
892 static inline int sane_case(int x, int high)
894 if (sane_istest(x, GIT_ALPHA))
895 x = (x & ~0x20) | high;
896 return x;
899 static inline int sane_iscase(int x, int is_lower)
901 if (!sane_istest(x, GIT_ALPHA))
902 return 0;
904 if (is_lower)
905 return (x & 0x20) != 0;
906 else
907 return (x & 0x20) == 0;
910 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
912 unsigned long ul;
913 char *p;
915 errno = 0;
916 /* negative values would be accepted by strtoul */
917 if (strchr(s, '-'))
918 return -1;
919 ul = strtoul(s, &p, base);
920 if (errno || *p || p == s || (unsigned int) ul != ul)
921 return -1;
922 *result = ul;
923 return 0;
926 static inline int strtol_i(char const *s, int base, int *result)
928 long ul;
929 char *p;
931 errno = 0;
932 ul = strtol(s, &p, base);
933 if (errno || *p || p == s || (int) ul != ul)
934 return -1;
935 *result = ul;
936 return 0;
939 #ifdef INTERNAL_QSORT
940 void git_qsort(void *base, size_t nmemb, size_t size,
941 int(*compar)(const void *, const void *));
942 #define qsort git_qsort
943 #endif
945 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
946 # define FORCE_DIR_SET_GID S_ISGID
947 #else
948 # define FORCE_DIR_SET_GID 0
949 #endif
951 #ifdef NO_NSEC
952 #undef USE_NSEC
953 #define ST_CTIME_NSEC(st) 0
954 #define ST_MTIME_NSEC(st) 0
955 #else
956 #ifdef USE_ST_TIMESPEC
957 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
958 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
959 #else
960 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
961 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
962 #endif
963 #endif
965 #ifdef UNRELIABLE_FSTAT
966 #define fstat_is_reliable() 0
967 #else
968 #define fstat_is_reliable() 1
969 #endif
971 #ifndef va_copy
973 * Since an obvious implementation of va_list would be to make it a
974 * pointer into the stack frame, a simple assignment will work on
975 * many systems. But let's try to be more portable.
977 #ifdef __va_copy
978 #define va_copy(dst, src) __va_copy(dst, src)
979 #else
980 #define va_copy(dst, src) ((dst) = (src))
981 #endif
982 #endif
984 #if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
985 #define HAVE_VARIADIC_MACROS 1
986 #endif
989 * Preserves errno, prints a message, but gives no warning for ENOENT.
990 * Returns 0 on success, which includes trying to unlink an object that does
991 * not exist.
993 int unlink_or_warn(const char *path);
995 * Tries to unlink file. Returns 0 if unlink succeeded
996 * or the file already didn't exist. Returns -1 and
997 * appends a message to err suitable for
998 * 'error("%s", err->buf)' on error.
1000 int unlink_or_msg(const char *file, struct strbuf *err);
1002 * Preserves errno, prints a message, but gives no warning for ENOENT.
1003 * Returns 0 on success, which includes trying to remove a directory that does
1004 * not exist.
1006 int rmdir_or_warn(const char *path);
1008 * Calls the correct function out of {unlink,rmdir}_or_warn based on
1009 * the supplied file mode.
1011 int remove_or_warn(unsigned int mode, const char *path);
1014 * Call access(2), but warn for any error except "missing file"
1015 * (ENOENT or ENOTDIR).
1017 #define ACCESS_EACCES_OK (1U << 0)
1018 int access_or_warn(const char *path, int mode, unsigned flag);
1019 int access_or_die(const char *path, int mode, unsigned flag);
1021 /* Warn on an inaccessible file that ought to be accessible */
1022 void warn_on_inaccessible(const char *path);
1024 #ifdef GMTIME_UNRELIABLE_ERRORS
1025 struct tm *git_gmtime(const time_t *);
1026 struct tm *git_gmtime_r(const time_t *, struct tm *);
1027 #define gmtime git_gmtime
1028 #define gmtime_r git_gmtime_r
1029 #endif
1031 #if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1032 #define USE_PARENS_AROUND_GETTEXT_N 1
1033 #endif
1035 #ifndef SHELL_PATH
1036 # define SHELL_PATH "/bin/sh"
1037 #endif
1039 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1040 #define flockfile(fh)
1041 #define funlockfile(fh)
1042 #define getc_unlocked(fh) getc(fh)
1043 #endif
1045 #endif