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[git/jnareb-git.git] / git-compat-util.h
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1 #ifndef GIT_COMPAT_UTIL_H
2 #define GIT_COMPAT_UTIL_H
4 #define _FILE_OFFSET_BITS 64
6 #ifndef FLEX_ARRAY
7 /*
8 * See if our compiler is known to support flexible array members.
9 */
10 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && (!defined(__SUNPRO_C) || (__SUNPRO_C > 0x580))
11 # define FLEX_ARRAY /* empty */
12 #elif defined(__GNUC__)
13 # if (__GNUC__ >= 3)
14 # define FLEX_ARRAY /* empty */
15 # else
16 # define FLEX_ARRAY 0 /* older GNU extension */
17 # endif
18 #endif
21 * Otherwise, default to safer but a bit wasteful traditional style
23 #ifndef FLEX_ARRAY
24 # define FLEX_ARRAY 1
25 #endif
26 #endif
28 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
29 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
31 #define maximum_signed_value_of_type(a) \
32 (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
34 #define maximum_unsigned_value_of_type(a) \
35 (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
38 * Signed integer overflow is undefined in C, so here's a helper macro
39 * to detect if the sum of two integers will overflow.
41 * Requires: a >= 0, typeof(a) equals typeof(b)
43 #define signed_add_overflows(a, b) \
44 ((b) > maximum_signed_value_of_type(a) - (a))
46 #define unsigned_add_overflows(a, b) \
47 ((b) > maximum_unsigned_value_of_type(a) - (a))
49 #ifdef __GNUC__
50 #define TYPEOF(x) (__typeof__(x))
51 #else
52 #define TYPEOF(x)
53 #endif
55 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
56 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
58 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
60 /* Approximation of the length of the decimal representation of this type. */
61 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
63 #if defined(__sun__)
65 * On Solaris, when _XOPEN_EXTENDED is set, its header file
66 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
67 * setting to say we are XPG5 or XPG6. Also on Solaris,
68 * XPG6 programs must be compiled with a c99 compiler, while
69 * non XPG6 programs must be compiled with a pre-c99 compiler.
71 # if __STDC_VERSION__ - 0 >= 199901L
72 # define _XOPEN_SOURCE 600
73 # else
74 # define _XOPEN_SOURCE 500
75 # endif
76 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
77 !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
78 !defined(__TANDEM)
79 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
80 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
81 #endif
82 #define _ALL_SOURCE 1
83 #define _GNU_SOURCE 1
84 #define _BSD_SOURCE 1
85 #define _NETBSD_SOURCE 1
86 #define _SGI_SOURCE 1
88 #ifdef WIN32 /* Both MinGW and MSVC */
89 #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
90 #include <winsock2.h>
91 #include <windows.h>
92 #endif
94 #include <unistd.h>
95 #include <stdio.h>
96 #include <sys/stat.h>
97 #include <fcntl.h>
98 #include <stddef.h>
99 #include <stdlib.h>
100 #include <stdarg.h>
101 #include <string.h>
102 #ifdef __TANDEM /* or HAVE_STRINGS_H or !NO_STRINGS_H? */
103 #include <strings.h> /* for strcasecmp() */
104 #endif
105 #include <errno.h>
106 #include <limits.h>
107 #include <sys/param.h>
108 #include <sys/types.h>
109 #include <dirent.h>
110 #include <sys/time.h>
111 #include <time.h>
112 #include <signal.h>
113 #include <fnmatch.h>
114 #include <assert.h>
115 #include <regex.h>
116 #include <utime.h>
117 #include <syslog.h>
118 #ifndef NO_SYS_POLL_H
119 #include <sys/poll.h>
120 #else
121 #include <poll.h>
122 #endif
123 #if defined(__MINGW32__)
124 /* pull in Windows compatibility stuff */
125 #include "compat/mingw.h"
126 #elif defined(_MSC_VER)
127 #include "compat/msvc.h"
128 #else
129 #include <sys/wait.h>
130 #include <sys/resource.h>
131 #include <sys/socket.h>
132 #include <sys/ioctl.h>
133 #include <termios.h>
134 #ifndef NO_SYS_SELECT_H
135 #include <sys/select.h>
136 #endif
137 #include <netinet/in.h>
138 #include <netinet/tcp.h>
139 #include <arpa/inet.h>
140 #include <netdb.h>
141 #include <pwd.h>
142 #include <sys/un.h>
143 #ifndef NO_INTTYPES_H
144 #include <inttypes.h>
145 #else
146 #include <stdint.h>
147 #endif
148 #ifdef NO_INTPTR_T
150 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
151 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
152 * while on IP16 and IP16L32 it is "int" (resp. "short")
153 * Size needs to match (or exceed) 'sizeof(void *)'.
154 * We can't take "long long" here as not everybody has it.
156 typedef long intptr_t;
157 typedef unsigned long uintptr_t;
158 #endif
159 #if defined(__CYGWIN__)
160 #undef _XOPEN_SOURCE
161 #include <grp.h>
162 #define _XOPEN_SOURCE 600
163 #include "compat/cygwin.h"
164 #else
165 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
166 #include <grp.h>
167 #define _ALL_SOURCE 1
168 #endif
169 #endif
171 /* used on Mac OS X */
172 #ifdef PRECOMPOSE_UNICODE
173 #include "compat/precompose_utf8.h"
174 #else
175 #define precompose_str(in,i_nfd2nfc)
176 #define precompose_argv(c,v)
177 #define probe_utf8_pathname_composition(a,b)
178 #endif
180 #ifdef MKDIR_WO_TRAILING_SLASH
181 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
182 extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
183 #endif
185 #ifdef NO_STRUCT_ITIMERVAL
186 struct itimerval {
187 struct timeval it_interval;
188 struct timeval it_value;
190 #endif
192 #ifdef NO_SETITIMER
193 #define setitimer(which,value,ovalue)
194 #endif
196 #ifndef NO_LIBGEN_H
197 #include <libgen.h>
198 #else
199 #define basename gitbasename
200 extern char *gitbasename(char *);
201 #endif
203 #ifndef NO_ICONV
204 #include <iconv.h>
205 #endif
207 #ifndef NO_OPENSSL
208 #include <openssl/ssl.h>
209 #include <openssl/err.h>
210 #endif
212 /* On most systems <limits.h> would have given us this, but
213 * not on some systems (e.g. GNU/Hurd).
215 #ifndef PATH_MAX
216 #define PATH_MAX 4096
217 #endif
219 #ifndef PRIuMAX
220 #define PRIuMAX "llu"
221 #endif
223 #ifndef PRIu32
224 #define PRIu32 "u"
225 #endif
227 #ifndef PRIx32
228 #define PRIx32 "x"
229 #endif
231 #ifndef PRIo32
232 #define PRIo32 "o"
233 #endif
235 #ifndef PATH_SEP
236 #define PATH_SEP ':'
237 #endif
239 #ifdef HAVE_PATHS_H
240 #include <paths.h>
241 #endif
242 #ifndef _PATH_DEFPATH
243 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
244 #endif
246 #ifndef STRIP_EXTENSION
247 #define STRIP_EXTENSION ""
248 #endif
250 #ifndef has_dos_drive_prefix
251 #define has_dos_drive_prefix(path) 0
252 #endif
254 #ifndef is_dir_sep
255 #define is_dir_sep(c) ((c) == '/')
256 #endif
258 #ifndef find_last_dir_sep
259 #define find_last_dir_sep(path) strrchr(path, '/')
260 #endif
262 #if defined(__HP_cc) && (__HP_cc >= 61000)
263 #define NORETURN __attribute__((noreturn))
264 #define NORETURN_PTR
265 #elif defined(__GNUC__) && !defined(NO_NORETURN)
266 #define NORETURN __attribute__((__noreturn__))
267 #define NORETURN_PTR __attribute__((__noreturn__))
268 #elif defined(_MSC_VER)
269 #define NORETURN __declspec(noreturn)
270 #define NORETURN_PTR
271 #else
272 #define NORETURN
273 #define NORETURN_PTR
274 #ifndef __attribute__
275 #define __attribute__(x)
276 #endif
277 #endif
279 #include "compat/bswap.h"
281 /* General helper functions */
282 extern void vreportf(const char *prefix, const char *err, va_list params);
283 extern void vwritef(int fd, const char *prefix, const char *err, va_list params);
284 extern NORETURN void usage(const char *err);
285 extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
286 extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
287 extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
288 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
289 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
291 extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
292 extern void set_error_routine(void (*routine)(const char *err, va_list params));
294 extern int prefixcmp(const char *str, const char *prefix);
295 extern int suffixcmp(const char *str, const char *suffix);
297 static inline const char *skip_prefix(const char *str, const char *prefix)
299 size_t len = strlen(prefix);
300 return strncmp(str, prefix, len) ? NULL : str + len;
303 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
305 #ifndef PROT_READ
306 #define PROT_READ 1
307 #define PROT_WRITE 2
308 #define MAP_PRIVATE 1
309 #endif
311 #define mmap git_mmap
312 #define munmap git_munmap
313 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
314 extern int git_munmap(void *start, size_t length);
316 #else /* NO_MMAP || USE_WIN32_MMAP */
318 #include <sys/mman.h>
320 #endif /* NO_MMAP || USE_WIN32_MMAP */
322 #ifdef NO_MMAP
324 /* This value must be multiple of (pagesize * 2) */
325 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
327 #else /* NO_MMAP */
329 /* This value must be multiple of (pagesize * 2) */
330 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
331 (sizeof(void*) >= 8 \
332 ? 1 * 1024 * 1024 * 1024 \
333 : 32 * 1024 * 1024)
335 #endif /* NO_MMAP */
337 #ifndef MAP_FAILED
338 #define MAP_FAILED ((void *)-1)
339 #endif
341 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
342 #define on_disk_bytes(st) ((st).st_size)
343 #else
344 #define on_disk_bytes(st) ((st).st_blocks * 512)
345 #endif
347 #define DEFAULT_PACKED_GIT_LIMIT \
348 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
350 #ifdef NO_PREAD
351 #define pread git_pread
352 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
353 #endif
355 * Forward decl that will remind us if its twin in cache.h changes.
356 * This function is used in compat/pread.c. But we can't include
357 * cache.h there.
359 extern ssize_t read_in_full(int fd, void *buf, size_t count);
361 #ifdef NO_SETENV
362 #define setenv gitsetenv
363 extern int gitsetenv(const char *, const char *, int);
364 #endif
366 #ifdef NO_MKDTEMP
367 #define mkdtemp gitmkdtemp
368 extern char *gitmkdtemp(char *);
369 #endif
371 #ifdef NO_MKSTEMPS
372 #define mkstemps gitmkstemps
373 extern int gitmkstemps(char *, int);
374 #endif
376 #ifdef NO_UNSETENV
377 #define unsetenv gitunsetenv
378 extern void gitunsetenv(const char *);
379 #endif
381 #ifdef NO_STRCASESTR
382 #define strcasestr gitstrcasestr
383 extern char *gitstrcasestr(const char *haystack, const char *needle);
384 #endif
386 #ifdef NO_STRLCPY
387 #define strlcpy gitstrlcpy
388 extern size_t gitstrlcpy(char *, const char *, size_t);
389 #endif
391 #ifdef NO_STRTOUMAX
392 #define strtoumax gitstrtoumax
393 extern uintmax_t gitstrtoumax(const char *, char **, int);
394 #define strtoimax gitstrtoimax
395 extern intmax_t gitstrtoimax(const char *, char **, int);
396 #endif
398 #ifdef NO_STRTOK_R
399 #define strtok_r gitstrtok_r
400 extern char *gitstrtok_r(char *s, const char *delim, char **save_ptr);
401 #endif
403 #ifdef NO_HSTRERROR
404 #define hstrerror githstrerror
405 extern const char *githstrerror(int herror);
406 #endif
408 #ifdef NO_MEMMEM
409 #define memmem gitmemmem
410 void *gitmemmem(const void *haystack, size_t haystacklen,
411 const void *needle, size_t needlelen);
412 #endif
414 #ifdef FREAD_READS_DIRECTORIES
415 #ifdef fopen
416 #undef fopen
417 #endif
418 #define fopen(a,b) git_fopen(a,b)
419 extern FILE *git_fopen(const char*, const char*);
420 #endif
422 #ifdef SNPRINTF_RETURNS_BOGUS
423 #define snprintf git_snprintf
424 extern int git_snprintf(char *str, size_t maxsize,
425 const char *format, ...);
426 #define vsnprintf git_vsnprintf
427 extern int git_vsnprintf(char *str, size_t maxsize,
428 const char *format, va_list ap);
429 #endif
431 #ifdef __GLIBC_PREREQ
432 #if __GLIBC_PREREQ(2, 1)
433 #define HAVE_STRCHRNUL
434 #define HAVE_MEMPCPY
435 #endif
436 #endif
438 #ifndef HAVE_STRCHRNUL
439 #define strchrnul gitstrchrnul
440 static inline char *gitstrchrnul(const char *s, int c)
442 while (*s && *s != c)
443 s++;
444 return (char *)s;
446 #endif
448 #ifndef HAVE_MEMPCPY
449 #define mempcpy gitmempcpy
450 static inline void *gitmempcpy(void *dest, const void *src, size_t n)
452 return (char *)memcpy(dest, src, n) + n;
454 #endif
456 #ifdef NO_INET_PTON
457 int inet_pton(int af, const char *src, void *dst);
458 #endif
460 #ifdef NO_INET_NTOP
461 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
462 #endif
464 extern void release_pack_memory(size_t, int);
466 typedef void (*try_to_free_t)(size_t);
467 extern try_to_free_t set_try_to_free_routine(try_to_free_t);
469 extern char *xstrdup(const char *str);
470 extern void *xmalloc(size_t size);
471 extern void *xmallocz(size_t size);
472 extern void *xmemdupz(const void *data, size_t len);
473 extern char *xstrndup(const char *str, size_t len);
474 extern void *xrealloc(void *ptr, size_t size);
475 extern void *xcalloc(size_t nmemb, size_t size);
476 extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
477 extern ssize_t xread(int fd, void *buf, size_t len);
478 extern ssize_t xwrite(int fd, const void *buf, size_t len);
479 extern int xdup(int fd);
480 extern FILE *xfdopen(int fd, const char *mode);
481 extern int xmkstemp(char *template);
482 extern int xmkstemp_mode(char *template, int mode);
483 extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
484 extern int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1);
486 static inline size_t xsize_t(off_t len)
488 if (len > (size_t) len)
489 die("Cannot handle files this big");
490 return (size_t)len;
493 static inline int has_extension(const char *filename, const char *ext)
495 size_t len = strlen(filename);
496 size_t extlen = strlen(ext);
497 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
500 /* in ctype.c, for kwset users */
501 extern const char tolower_trans_tbl[256];
503 /* Sane ctype - no locale, and works with signed chars */
504 #undef isascii
505 #undef isspace
506 #undef isdigit
507 #undef isalpha
508 #undef isalnum
509 #undef isprint
510 #undef islower
511 #undef isupper
512 #undef tolower
513 #undef toupper
514 extern unsigned char sane_ctype[256];
515 #define GIT_SPACE 0x01
516 #define GIT_DIGIT 0x02
517 #define GIT_ALPHA 0x04
518 #define GIT_GLOB_SPECIAL 0x08
519 #define GIT_REGEX_SPECIAL 0x10
520 #define GIT_PATHSPEC_MAGIC 0x20
521 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
522 #define isascii(x) (((x) & ~0x7f) == 0)
523 #define isspace(x) sane_istest(x,GIT_SPACE)
524 #define isdigit(x) sane_istest(x,GIT_DIGIT)
525 #define isalpha(x) sane_istest(x,GIT_ALPHA)
526 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
527 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
528 #define islower(x) sane_iscase(x, 1)
529 #define isupper(x) sane_iscase(x, 0)
530 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
531 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
532 #define tolower(x) sane_case((unsigned char)(x), 0x20)
533 #define toupper(x) sane_case((unsigned char)(x), 0)
534 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
536 static inline int sane_case(int x, int high)
538 if (sane_istest(x, GIT_ALPHA))
539 x = (x & ~0x20) | high;
540 return x;
543 static inline int sane_iscase(int x, int is_lower)
545 if (!sane_istest(x, GIT_ALPHA))
546 return 0;
548 if (is_lower)
549 return (x & 0x20) != 0;
550 else
551 return (x & 0x20) == 0;
554 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
556 unsigned long ul;
557 char *p;
559 errno = 0;
560 ul = strtoul(s, &p, base);
561 if (errno || *p || p == s || (unsigned int) ul != ul)
562 return -1;
563 *result = ul;
564 return 0;
567 static inline int strtol_i(char const *s, int base, int *result)
569 long ul;
570 char *p;
572 errno = 0;
573 ul = strtol(s, &p, base);
574 if (errno || *p || p == s || (int) ul != ul)
575 return -1;
576 *result = ul;
577 return 0;
580 #ifdef INTERNAL_QSORT
581 void git_qsort(void *base, size_t nmemb, size_t size,
582 int(*compar)(const void *, const void *));
583 #define qsort git_qsort
584 #endif
586 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
587 # define FORCE_DIR_SET_GID S_ISGID
588 #else
589 # define FORCE_DIR_SET_GID 0
590 #endif
592 #ifdef NO_NSEC
593 #undef USE_NSEC
594 #define ST_CTIME_NSEC(st) 0
595 #define ST_MTIME_NSEC(st) 0
596 #else
597 #ifdef USE_ST_TIMESPEC
598 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
599 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
600 #else
601 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
602 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
603 #endif
604 #endif
606 #ifdef UNRELIABLE_FSTAT
607 #define fstat_is_reliable() 0
608 #else
609 #define fstat_is_reliable() 1
610 #endif
612 #ifndef va_copy
614 * Since an obvious implementation of va_list would be to make it a
615 * pointer into the stack frame, a simple assignment will work on
616 * many systems. But let's try to be more portable.
618 #ifdef __va_copy
619 #define va_copy(dst, src) __va_copy(dst, src)
620 #else
621 #define va_copy(dst, src) ((dst) = (src))
622 #endif
623 #endif
626 * Preserves errno, prints a message, but gives no warning for ENOENT.
627 * Always returns the return value of unlink(2).
629 int unlink_or_warn(const char *path);
631 * Likewise for rmdir(2).
633 int rmdir_or_warn(const char *path);
635 * Calls the correct function out of {unlink,rmdir}_or_warn based on
636 * the supplied file mode.
638 int remove_or_warn(unsigned int mode, const char *path);
641 * Call access(2), but warn for any error except "missing file"
642 * (ENOENT or ENOTDIR).
644 int access_or_warn(const char *path, int mode);
645 int access_or_die(const char *path, int mode);
647 /* Warn on an inaccessible file that ought to be accessible */
648 void warn_on_inaccessible(const char *path);
650 /* Get the passwd entry for the UID of the current process. */
651 struct passwd *xgetpwuid_self(void);
653 #endif