Documentation updates for 'GIT_WORK_TREE without GIT_DIR' historical usecase
[git/jnareb-git/bp-gitweb.git] / git-compat-util.h
blobd6d269f138b06791ba6e8712b06036f00a73c7e3
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)))
35 * Signed integer overflow is undefined in C, so here's a helper macro
36 * to detect if the sum of two integers will overflow.
38 * Requires: a >= 0, typeof(a) equals typeof(b)
40 #define signed_add_overflows(a, b) \
41 ((b) > maximum_signed_value_of_type(a) - (a))
43 #ifdef __GNUC__
44 #define TYPEOF(x) (__typeof__(x))
45 #else
46 #define TYPEOF(x)
47 #endif
49 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
50 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
52 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
54 /* Approximation of the length of the decimal representation of this type. */
55 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
57 #if defined(__sun__)
59 * On Solaris, when _XOPEN_EXTENDED is set, its header file
60 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
61 * setting to say we are XPG5 or XPG6. Also on Solaris,
62 * XPG6 programs must be compiled with a c99 compiler, while
63 * non XPG6 programs must be compiled with a pre-c99 compiler.
65 # if __STDC_VERSION__ - 0 >= 199901L
66 # define _XOPEN_SOURCE 600
67 # else
68 # define _XOPEN_SOURCE 500
69 # endif
70 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
71 !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__)
72 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
73 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
74 #endif
75 #define _ALL_SOURCE 1
76 #define _GNU_SOURCE 1
77 #define _BSD_SOURCE 1
78 #define _NETBSD_SOURCE 1
79 #define _SGI_SOURCE 1
81 #ifdef WIN32 /* Both MinGW and MSVC */
82 #define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
83 #include <winsock2.h>
84 #include <windows.h>
85 #endif
87 #include <unistd.h>
88 #include <stdio.h>
89 #include <sys/stat.h>
90 #include <fcntl.h>
91 #include <stddef.h>
92 #include <stdlib.h>
93 #include <stdarg.h>
94 #include <string.h>
95 #include <errno.h>
96 #include <limits.h>
97 #include <sys/param.h>
98 #include <sys/types.h>
99 #include <dirent.h>
100 #include <sys/time.h>
101 #include <time.h>
102 #include <signal.h>
103 #include <fnmatch.h>
104 #include <assert.h>
105 #include <regex.h>
106 #include <utime.h>
107 #include <syslog.h>
108 #ifndef NO_SYS_POLL_H
109 #include <sys/poll.h>
110 #else
111 #include <poll.h>
112 #endif
113 #ifndef __MINGW32__
114 #include <sys/wait.h>
115 #include <sys/socket.h>
116 #include <sys/ioctl.h>
117 #include <termios.h>
118 #ifndef NO_SYS_SELECT_H
119 #include <sys/select.h>
120 #endif
121 #include <netinet/in.h>
122 #include <netinet/tcp.h>
123 #include <arpa/inet.h>
124 #include <netdb.h>
125 #include <pwd.h>
126 #ifndef NO_INTTYPES_H
127 #include <inttypes.h>
128 #else
129 #include <stdint.h>
130 #endif
131 #if defined(__CYGWIN__)
132 #undef _XOPEN_SOURCE
133 #include <grp.h>
134 #define _XOPEN_SOURCE 600
135 #include "compat/cygwin.h"
136 #else
137 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
138 #include <grp.h>
139 #define _ALL_SOURCE 1
140 #endif
141 #else /* __MINGW32__ */
142 /* pull in Windows compatibility stuff */
143 #include "compat/mingw.h"
144 #endif /* __MINGW32__ */
145 #ifdef _MSC_VER
146 #include "compat/msvc.h"
147 #endif
149 #ifndef NO_LIBGEN_H
150 #include <libgen.h>
151 #else
152 #define basename gitbasename
153 extern char *gitbasename(char *);
154 #endif
156 #ifndef NO_ICONV
157 #include <iconv.h>
158 #endif
160 #ifndef NO_OPENSSL
161 #include <openssl/ssl.h>
162 #include <openssl/err.h>
163 #endif
165 /* On most systems <limits.h> would have given us this, but
166 * not on some systems (e.g. GNU/Hurd).
168 #ifndef PATH_MAX
169 #define PATH_MAX 4096
170 #endif
172 #ifndef PRIuMAX
173 #define PRIuMAX "llu"
174 #endif
176 #ifndef PRIu32
177 #define PRIu32 "u"
178 #endif
180 #ifndef PRIx32
181 #define PRIx32 "x"
182 #endif
184 #ifndef PRIo32
185 #define PRIo32 "o"
186 #endif
188 #ifndef PATH_SEP
189 #define PATH_SEP ':'
190 #endif
192 #ifdef HAVE_PATHS_H
193 #include <paths.h>
194 #endif
195 #ifndef _PATH_DEFPATH
196 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
197 #endif
199 #ifndef STRIP_EXTENSION
200 #define STRIP_EXTENSION ""
201 #endif
203 #ifndef has_dos_drive_prefix
204 #define has_dos_drive_prefix(path) 0
205 #endif
207 #ifndef is_dir_sep
208 #define is_dir_sep(c) ((c) == '/')
209 #endif
211 #ifdef __GNUC__
212 #define NORETURN __attribute__((__noreturn__))
213 #define NORETURN_PTR __attribute__((__noreturn__))
214 #elif defined(_MSC_VER)
215 #define NORETURN __declspec(noreturn)
216 #define NORETURN_PTR
217 #else
218 #define NORETURN
219 #define NORETURN_PTR
220 #ifndef __attribute__
221 #define __attribute__(x)
222 #endif
223 #endif
225 #include "compat/bswap.h"
227 /* General helper functions */
228 extern void vreportf(const char *prefix, const char *err, va_list params);
229 extern NORETURN void usage(const char *err);
230 extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
231 extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
232 extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
233 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
234 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
236 extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
238 extern int prefixcmp(const char *str, const char *prefix);
239 extern int suffixcmp(const char *str, const char *suffix);
241 static inline const char *skip_prefix(const char *str, const char *prefix)
243 size_t len = strlen(prefix);
244 return strncmp(str, prefix, len) ? NULL : str + len;
247 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
249 #ifndef PROT_READ
250 #define PROT_READ 1
251 #define PROT_WRITE 2
252 #define MAP_PRIVATE 1
253 #endif
255 #define mmap git_mmap
256 #define munmap git_munmap
257 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
258 extern int git_munmap(void *start, size_t length);
260 #else /* NO_MMAP || USE_WIN32_MMAP */
262 #include <sys/mman.h>
264 #endif /* NO_MMAP || USE_WIN32_MMAP */
266 #ifdef NO_MMAP
268 /* This value must be multiple of (pagesize * 2) */
269 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
271 #else /* NO_MMAP */
273 /* This value must be multiple of (pagesize * 2) */
274 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
275 (sizeof(void*) >= 8 \
276 ? 1 * 1024 * 1024 * 1024 \
277 : 32 * 1024 * 1024)
279 #endif /* NO_MMAP */
281 #ifndef MAP_FAILED
282 #define MAP_FAILED ((void *)-1)
283 #endif
285 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
286 #define on_disk_bytes(st) ((st).st_size)
287 #else
288 #define on_disk_bytes(st) ((st).st_blocks * 512)
289 #endif
291 #define DEFAULT_PACKED_GIT_LIMIT \
292 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
294 #ifdef NO_PREAD
295 #define pread git_pread
296 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
297 #endif
299 * Forward decl that will remind us if its twin in cache.h changes.
300 * This function is used in compat/pread.c. But we can't include
301 * cache.h there.
303 extern ssize_t read_in_full(int fd, void *buf, size_t count);
305 #ifdef NO_SETENV
306 #define setenv gitsetenv
307 extern int gitsetenv(const char *, const char *, int);
308 #endif
310 #ifdef NO_MKDTEMP
311 #define mkdtemp gitmkdtemp
312 extern char *gitmkdtemp(char *);
313 #endif
315 #ifdef NO_MKSTEMPS
316 #define mkstemps gitmkstemps
317 extern int gitmkstemps(char *, int);
318 #endif
320 #ifdef NO_UNSETENV
321 #define unsetenv gitunsetenv
322 extern void gitunsetenv(const char *);
323 #endif
325 #ifdef NO_STRCASESTR
326 #define strcasestr gitstrcasestr
327 extern char *gitstrcasestr(const char *haystack, const char *needle);
328 #endif
330 #ifdef NO_STRLCPY
331 #define strlcpy gitstrlcpy
332 extern size_t gitstrlcpy(char *, const char *, size_t);
333 #endif
335 #ifdef NO_STRTOUMAX
336 #define strtoumax gitstrtoumax
337 extern uintmax_t gitstrtoumax(const char *, char **, int);
338 #endif
340 #ifdef NO_STRTOK_R
341 #define strtok_r gitstrtok_r
342 extern char *gitstrtok_r(char *s, const char *delim, char **save_ptr);
343 #endif
345 #ifdef NO_HSTRERROR
346 #define hstrerror githstrerror
347 extern const char *githstrerror(int herror);
348 #endif
350 #ifdef NO_MEMMEM
351 #define memmem gitmemmem
352 void *gitmemmem(const void *haystack, size_t haystacklen,
353 const void *needle, size_t needlelen);
354 #endif
356 #ifdef FREAD_READS_DIRECTORIES
357 #ifdef fopen
358 #undef fopen
359 #endif
360 #define fopen(a,b) git_fopen(a,b)
361 extern FILE *git_fopen(const char*, const char*);
362 #endif
364 #ifdef SNPRINTF_RETURNS_BOGUS
365 #define snprintf git_snprintf
366 extern int git_snprintf(char *str, size_t maxsize,
367 const char *format, ...);
368 #define vsnprintf git_vsnprintf
369 extern int git_vsnprintf(char *str, size_t maxsize,
370 const char *format, va_list ap);
371 #endif
373 #ifdef __GLIBC_PREREQ
374 #if __GLIBC_PREREQ(2, 1)
375 #define HAVE_STRCHRNUL
376 #define HAVE_MEMPCPY
377 #endif
378 #endif
380 #ifndef HAVE_STRCHRNUL
381 #define strchrnul gitstrchrnul
382 static inline char *gitstrchrnul(const char *s, int c)
384 while (*s && *s != c)
385 s++;
386 return (char *)s;
388 #endif
390 #ifndef HAVE_MEMPCPY
391 #define mempcpy gitmempcpy
392 static inline void *gitmempcpy(void *dest, const void *src, size_t n)
394 return (char *)memcpy(dest, src, n) + n;
396 #endif
398 #ifdef NO_INET_PTON
399 int inet_pton(int af, const char *src, void *dst);
400 #endif
402 #ifdef NO_INET_NTOP
403 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
404 #endif
406 extern void release_pack_memory(size_t, int);
408 typedef void (*try_to_free_t)(size_t);
409 extern try_to_free_t set_try_to_free_routine(try_to_free_t);
411 extern char *xstrdup(const char *str);
412 extern void *xmalloc(size_t size);
413 extern void *xmallocz(size_t size);
414 extern void *xmemdupz(const void *data, size_t len);
415 extern char *xstrndup(const char *str, size_t len);
416 extern void *xrealloc(void *ptr, size_t size);
417 extern void *xcalloc(size_t nmemb, size_t size);
418 extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
419 extern ssize_t xread(int fd, void *buf, size_t len);
420 extern ssize_t xwrite(int fd, const void *buf, size_t len);
421 extern int xdup(int fd);
422 extern FILE *xfdopen(int fd, const char *mode);
423 extern int xmkstemp(char *template);
424 extern int xmkstemp_mode(char *template, int mode);
425 extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
426 extern int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1);
428 static inline size_t xsize_t(off_t len)
430 if (len > (size_t) len)
431 die("Cannot handle files this big");
432 return (size_t)len;
435 static inline int has_extension(const char *filename, const char *ext)
437 size_t len = strlen(filename);
438 size_t extlen = strlen(ext);
439 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
442 /* Sane ctype - no locale, and works with signed chars */
443 #undef isascii
444 #undef isspace
445 #undef isdigit
446 #undef isalpha
447 #undef isalnum
448 #undef tolower
449 #undef toupper
450 extern unsigned char sane_ctype[256];
451 #define GIT_SPACE 0x01
452 #define GIT_DIGIT 0x02
453 #define GIT_ALPHA 0x04
454 #define GIT_GLOB_SPECIAL 0x08
455 #define GIT_REGEX_SPECIAL 0x10
456 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
457 #define isascii(x) (((x) & ~0x7f) == 0)
458 #define isspace(x) sane_istest(x,GIT_SPACE)
459 #define isdigit(x) sane_istest(x,GIT_DIGIT)
460 #define isalpha(x) sane_istest(x,GIT_ALPHA)
461 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
462 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
463 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
464 #define tolower(x) sane_case((unsigned char)(x), 0x20)
465 #define toupper(x) sane_case((unsigned char)(x), 0)
467 static inline int sane_case(int x, int high)
469 if (sane_istest(x, GIT_ALPHA))
470 x = (x & ~0x20) | high;
471 return x;
474 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
476 unsigned long ul;
477 char *p;
479 errno = 0;
480 ul = strtoul(s, &p, base);
481 if (errno || *p || p == s || (unsigned int) ul != ul)
482 return -1;
483 *result = ul;
484 return 0;
487 static inline int strtol_i(char const *s, int base, int *result)
489 long ul;
490 char *p;
492 errno = 0;
493 ul = strtol(s, &p, base);
494 if (errno || *p || p == s || (int) ul != ul)
495 return -1;
496 *result = ul;
497 return 0;
500 #ifdef INTERNAL_QSORT
501 void git_qsort(void *base, size_t nmemb, size_t size,
502 int(*compar)(const void *, const void *));
503 #define qsort git_qsort
504 #endif
506 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
507 # define FORCE_DIR_SET_GID S_ISGID
508 #else
509 # define FORCE_DIR_SET_GID 0
510 #endif
512 #ifdef NO_NSEC
513 #undef USE_NSEC
514 #define ST_CTIME_NSEC(st) 0
515 #define ST_MTIME_NSEC(st) 0
516 #else
517 #ifdef USE_ST_TIMESPEC
518 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
519 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
520 #else
521 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
522 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
523 #endif
524 #endif
526 #ifdef UNRELIABLE_FSTAT
527 #define fstat_is_reliable() 0
528 #else
529 #define fstat_is_reliable() 1
530 #endif
533 * Preserves errno, prints a message, but gives no warning for ENOENT.
534 * Always returns the return value of unlink(2).
536 int unlink_or_warn(const char *path);
538 * Likewise for rmdir(2).
540 int rmdir_or_warn(const char *path);
542 * Calls the correct function out of {unlink,rmdir}_or_warn based on
543 * the supplied file mode.
545 int remove_or_warn(unsigned int mode, const char *path);
547 #endif