make sure byte swapping is optimal for git
[git/git.git] / git-compat-util.h
1 #ifndef GIT_COMPAT_UTIL_H
2 #define GIT_COMPAT_UTIL_H
3
4 #define _FILE_OFFSET_BITS 64
5
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
19
20 /*
21 * Otherwise, default to safer but a bit wasteful traditional style
22 */
23 #ifndef FLEX_ARRAY
24 # define FLEX_ARRAY 1
25 #endif
26 #endif
27
28 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
29 #define bitsizeof(x) (CHAR_BIT * sizeof(x))
30
31 #ifdef __GNUC__
32 #define TYPEOF(x) (__typeof__(x))
33 #else
34 #define TYPEOF(x)
35 #endif
36
37 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
38 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
39
40 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
41
42 /* Approximation of the length of the decimal representation of this type. */
43 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
44
45 #if defined(__sun__)
46 /*
47 * On Solaris, when _XOPEN_EXTENDED is set, its header file
48 * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
49 * setting to say we are XPG5 or XPG6. Also on Solaris,
50 * XPG6 programs must be compiled with a c99 compiler, while
51 * non XPG6 programs must be compiled with a pre-c99 compiler.
52 */
53 # if __STDC_VERSION__ - 0 >= 199901L
54 # define _XOPEN_SOURCE 600
55 # else
56 # define _XOPEN_SOURCE 500
57 # endif
58 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && !defined(_M_UNIX) && !defined(sgi)
59 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
60 #ifndef __sun__
61 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
62 #endif
63 #endif
64 #define _ALL_SOURCE 1
65 #define _GNU_SOURCE 1
66 #define _BSD_SOURCE 1
67 #define _NETBSD_SOURCE 1
68 #define _SGI_SOURCE 1
69
70 #include <unistd.h>
71 #include <stdio.h>
72 #include <sys/stat.h>
73 #include <fcntl.h>
74 #include <stddef.h>
75 #include <stdlib.h>
76 #include <stdarg.h>
77 #include <string.h>
78 #include <errno.h>
79 #include <limits.h>
80 #include <sys/param.h>
81 #include <sys/types.h>
82 #include <dirent.h>
83 #include <sys/time.h>
84 #include <time.h>
85 #include <signal.h>
86 #include <fnmatch.h>
87 #include <assert.h>
88 #include <regex.h>
89 #include <utime.h>
90 #ifndef __MINGW32__
91 #include <sys/wait.h>
92 #include <sys/poll.h>
93 #include <sys/socket.h>
94 #include <sys/ioctl.h>
95 #ifndef NO_SYS_SELECT_H
96 #include <sys/select.h>
97 #endif
98 #include <netinet/in.h>
99 #include <netinet/tcp.h>
100 #include <arpa/inet.h>
101 #include <netdb.h>
102 #include <pwd.h>
103 #include <inttypes.h>
104 #if defined(__CYGWIN__)
105 #undef _XOPEN_SOURCE
106 #include <grp.h>
107 #define _XOPEN_SOURCE 600
108 #include "compat/cygwin.h"
109 #else
110 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
111 #include <grp.h>
112 #define _ALL_SOURCE 1
113 #endif
114 #else /* __MINGW32__ */
115 /* pull in Windows compatibility stuff */
116 #include "compat/mingw.h"
117 #endif /* __MINGW32__ */
118
119 #ifndef NO_LIBGEN_H
120 #include <libgen.h>
121 #else
122 #define basename gitbasename
123 extern char *gitbasename(char *);
124 #endif
125
126 #ifndef NO_ICONV
127 #include <iconv.h>
128 #endif
129
130 #ifndef NO_OPENSSL
131 #include <openssl/ssl.h>
132 #include <openssl/err.h>
133 #endif
134
135 /* On most systems <limits.h> would have given us this, but
136 * not on some systems (e.g. GNU/Hurd).
137 */
138 #ifndef PATH_MAX
139 #define PATH_MAX 4096
140 #endif
141
142 #ifndef PRIuMAX
143 #define PRIuMAX "llu"
144 #endif
145
146 #ifndef PRIu32
147 #define PRIu32 "u"
148 #endif
149
150 #ifndef PRIx32
151 #define PRIx32 "x"
152 #endif
153
154 #ifndef PATH_SEP
155 #define PATH_SEP ':'
156 #endif
157
158 #ifndef STRIP_EXTENSION
159 #define STRIP_EXTENSION ""
160 #endif
161
162 #ifndef has_dos_drive_prefix
163 #define has_dos_drive_prefix(path) 0
164 #endif
165
166 #ifndef is_dir_sep
167 #define is_dir_sep(c) ((c) == '/')
168 #endif
169
170 #ifdef __GNUC__
171 #define NORETURN __attribute__((__noreturn__))
172 #else
173 #define NORETURN
174 #ifndef __attribute__
175 #define __attribute__(x)
176 #endif
177 #endif
178
179 #include "compat/bswap.h"
180
181 /* General helper functions */
182 extern void usage(const char *err) NORETURN;
183 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
184 extern void die_errno(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
185 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
186 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
187
188 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
189
190 extern int prefixcmp(const char *str, const char *prefix);
191 extern time_t tm_to_time_t(const struct tm *tm);
192
193 static inline const char *skip_prefix(const char *str, const char *prefix)
194 {
195 size_t len = strlen(prefix);
196 return strncmp(str, prefix, len) ? NULL : str + len;
197 }
198
199 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
200
201 #ifndef PROT_READ
202 #define PROT_READ 1
203 #define PROT_WRITE 2
204 #define MAP_PRIVATE 1
205 #define MAP_FAILED ((void*)-1)
206 #endif
207
208 #define mmap git_mmap
209 #define munmap git_munmap
210 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
211 extern int git_munmap(void *start, size_t length);
212
213 #else /* NO_MMAP || USE_WIN32_MMAP */
214
215 #include <sys/mman.h>
216
217 #endif /* NO_MMAP || USE_WIN32_MMAP */
218
219 #ifdef NO_MMAP
220
221 /* This value must be multiple of (pagesize * 2) */
222 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
223
224 #else /* NO_MMAP */
225
226 /* This value must be multiple of (pagesize * 2) */
227 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
228 (sizeof(void*) >= 8 \
229 ? 1 * 1024 * 1024 * 1024 \
230 : 32 * 1024 * 1024)
231
232 #endif /* NO_MMAP */
233
234 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
235 #define on_disk_bytes(st) ((st).st_size)
236 #else
237 #define on_disk_bytes(st) ((st).st_blocks * 512)
238 #endif
239
240 #define DEFAULT_PACKED_GIT_LIMIT \
241 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
242
243 #ifdef NO_PREAD
244 #define pread git_pread
245 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
246 #endif
247 /*
248 * Forward decl that will remind us if its twin in cache.h changes.
249 * This function is used in compat/pread.c. But we can't include
250 * cache.h there.
251 */
252 extern ssize_t read_in_full(int fd, void *buf, size_t count);
253
254 #ifdef NO_SETENV
255 #define setenv gitsetenv
256 extern int gitsetenv(const char *, const char *, int);
257 #endif
258
259 #ifdef NO_MKDTEMP
260 #define mkdtemp gitmkdtemp
261 extern char *gitmkdtemp(char *);
262 #endif
263
264 #ifdef NO_MKSTEMPS
265 #define mkstemps gitmkstemps
266 extern int gitmkstemps(char *, int);
267 #endif
268
269 #ifdef NO_UNSETENV
270 #define unsetenv gitunsetenv
271 extern void gitunsetenv(const char *);
272 #endif
273
274 #ifdef NO_STRCASESTR
275 #define strcasestr gitstrcasestr
276 extern char *gitstrcasestr(const char *haystack, const char *needle);
277 #endif
278
279 #ifdef NO_STRLCPY
280 #define strlcpy gitstrlcpy
281 extern size_t gitstrlcpy(char *, const char *, size_t);
282 #endif
283
284 #ifdef NO_STRTOUMAX
285 #define strtoumax gitstrtoumax
286 extern uintmax_t gitstrtoumax(const char *, char **, int);
287 #endif
288
289 #ifdef NO_HSTRERROR
290 #define hstrerror githstrerror
291 extern const char *githstrerror(int herror);
292 #endif
293
294 #ifdef NO_MEMMEM
295 #define memmem gitmemmem
296 void *gitmemmem(const void *haystack, size_t haystacklen,
297 const void *needle, size_t needlelen);
298 #endif
299
300 #ifdef FREAD_READS_DIRECTORIES
301 #ifdef fopen
302 #undef fopen
303 #endif
304 #define fopen(a,b) git_fopen(a,b)
305 extern FILE *git_fopen(const char*, const char*);
306 #endif
307
308 #ifdef SNPRINTF_RETURNS_BOGUS
309 #define snprintf git_snprintf
310 extern int git_snprintf(char *str, size_t maxsize,
311 const char *format, ...);
312 #define vsnprintf git_vsnprintf
313 extern int git_vsnprintf(char *str, size_t maxsize,
314 const char *format, va_list ap);
315 #endif
316
317 #ifdef __GLIBC_PREREQ
318 #if __GLIBC_PREREQ(2, 1)
319 #define HAVE_STRCHRNUL
320 #endif
321 #endif
322
323 #ifndef HAVE_STRCHRNUL
324 #define strchrnul gitstrchrnul
325 static inline char *gitstrchrnul(const char *s, int c)
326 {
327 while (*s && *s != c)
328 s++;
329 return (char *)s;
330 }
331 #endif
332
333 extern void release_pack_memory(size_t, int);
334
335 extern char *xstrdup(const char *str);
336 extern void *xmalloc(size_t size);
337 extern void *xmemdupz(const void *data, size_t len);
338 extern char *xstrndup(const char *str, size_t len);
339 extern void *xrealloc(void *ptr, size_t size);
340 extern void *xcalloc(size_t nmemb, size_t size);
341 extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
342 extern ssize_t xread(int fd, void *buf, size_t len);
343 extern ssize_t xwrite(int fd, const void *buf, size_t len);
344 extern int xdup(int fd);
345 extern FILE *xfdopen(int fd, const char *mode);
346 extern int xmkstemp(char *template);
347 extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
348 extern int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1);
349
350 static inline size_t xsize_t(off_t len)
351 {
352 return (size_t)len;
353 }
354
355 static inline int has_extension(const char *filename, const char *ext)
356 {
357 size_t len = strlen(filename);
358 size_t extlen = strlen(ext);
359 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
360 }
361
362 /* Sane ctype - no locale, and works with signed chars */
363 #undef isascii
364 #undef isspace
365 #undef isdigit
366 #undef isalpha
367 #undef isalnum
368 #undef tolower
369 #undef toupper
370 extern unsigned char sane_ctype[256];
371 #define GIT_SPACE 0x01
372 #define GIT_DIGIT 0x02
373 #define GIT_ALPHA 0x04
374 #define GIT_GLOB_SPECIAL 0x08
375 #define GIT_REGEX_SPECIAL 0x10
376 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
377 #define isascii(x) (((x) & ~0x7f) == 0)
378 #define isspace(x) sane_istest(x,GIT_SPACE)
379 #define isdigit(x) sane_istest(x,GIT_DIGIT)
380 #define isalpha(x) sane_istest(x,GIT_ALPHA)
381 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
382 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
383 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
384 #define tolower(x) sane_case((unsigned char)(x), 0x20)
385 #define toupper(x) sane_case((unsigned char)(x), 0)
386
387 static inline int sane_case(int x, int high)
388 {
389 if (sane_istest(x, GIT_ALPHA))
390 x = (x & ~0x20) | high;
391 return x;
392 }
393
394 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
395 {
396 unsigned long ul;
397 char *p;
398
399 errno = 0;
400 ul = strtoul(s, &p, base);
401 if (errno || *p || p == s || (unsigned int) ul != ul)
402 return -1;
403 *result = ul;
404 return 0;
405 }
406
407 static inline int strtol_i(char const *s, int base, int *result)
408 {
409 long ul;
410 char *p;
411
412 errno = 0;
413 ul = strtol(s, &p, base);
414 if (errno || *p || p == s || (int) ul != ul)
415 return -1;
416 *result = ul;
417 return 0;
418 }
419
420 #ifdef INTERNAL_QSORT
421 void git_qsort(void *base, size_t nmemb, size_t size,
422 int(*compar)(const void *, const void *));
423 #define qsort git_qsort
424 #endif
425
426 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
427 # define FORCE_DIR_SET_GID S_ISGID
428 #else
429 # define FORCE_DIR_SET_GID 0
430 #endif
431
432 #ifdef NO_NSEC
433 #undef USE_NSEC
434 #define ST_CTIME_NSEC(st) 0
435 #define ST_MTIME_NSEC(st) 0
436 #else
437 #ifdef USE_ST_TIMESPEC
438 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
439 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
440 #else
441 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
442 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
443 #endif
444 #endif
445
446 #ifdef UNRELIABLE_FSTAT
447 #define fstat_is_reliable() 0
448 #else
449 #define fstat_is_reliable() 1
450 #endif
451
452 /*
453 * Preserves errno, prints a message, but gives no warning for ENOENT.
454 * Always returns the return value of unlink(2).
455 */
456 int unlink_or_warn(const char *path);
457
458 #endif