git-merge-ours: make it a builtin.
[git/peff.git] / git-compat-util.h
blob86c896296686c94db6e9d0f2238a72aa383f647f
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)
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]))
30 #ifdef __GNUC__
31 #define TYPEOF(x) (__typeof__(x))
32 #else
33 #define TYPEOF(x)
34 #endif
36 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (sizeof(x) * 8 - (bits))))
37 #define HAS_MULTI_BITS(i) ((i) & ((i) - 1)) /* checks if an integer has more than 1 bit set */
39 /* Approximation of the length of the decimal representation of this type. */
40 #define decimal_length(x) ((int)(sizeof(x) * 2.56 + 0.5) + 1)
42 #if !defined(__APPLE__) && !defined(__FreeBSD__)
43 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
44 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
45 #endif
46 #define _ALL_SOURCE 1
47 #define _GNU_SOURCE 1
48 #define _BSD_SOURCE 1
50 #include <unistd.h>
51 #include <stdio.h>
52 #include <sys/stat.h>
53 #include <fcntl.h>
54 #include <stddef.h>
55 #include <stdlib.h>
56 #include <stdarg.h>
57 #include <string.h>
58 #include <errno.h>
59 #include <limits.h>
60 #include <sys/param.h>
61 #include <sys/types.h>
62 #include <dirent.h>
63 #include <sys/time.h>
64 #include <time.h>
65 #include <signal.h>
66 #include <sys/wait.h>
67 #include <fnmatch.h>
68 #include <sys/poll.h>
69 #include <sys/socket.h>
70 #include <assert.h>
71 #include <regex.h>
72 #include <netinet/in.h>
73 #include <netinet/tcp.h>
74 #include <arpa/inet.h>
75 #include <netdb.h>
76 #include <pwd.h>
77 #include <inttypes.h>
78 #if defined(__CYGWIN__)
79 #undef _XOPEN_SOURCE
80 #include <grp.h>
81 #define _XOPEN_SOURCE 600
82 #else
83 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
84 #include <grp.h>
85 #define _ALL_SOURCE 1
86 #endif
88 #ifndef NO_ICONV
89 #include <iconv.h>
90 #endif
92 /* On most systems <limits.h> would have given us this, but
93 * not on some systems (e.g. GNU/Hurd).
95 #ifndef PATH_MAX
96 #define PATH_MAX 4096
97 #endif
99 #ifndef PRIuMAX
100 #define PRIuMAX "llu"
101 #endif
103 #ifdef __GNUC__
104 #define NORETURN __attribute__((__noreturn__))
105 #else
106 #define NORETURN
107 #ifndef __attribute__
108 #define __attribute__(x)
109 #endif
110 #endif
112 /* General helper functions */
113 extern void usage(const char *err) NORETURN;
114 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
115 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
116 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
118 extern void set_usage_routine(void (*routine)(const char *err) NORETURN);
119 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
120 extern void set_error_routine(void (*routine)(const char *err, va_list params));
121 extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
123 #ifdef NO_MMAP
125 #ifndef PROT_READ
126 #define PROT_READ 1
127 #define PROT_WRITE 2
128 #define MAP_PRIVATE 1
129 #define MAP_FAILED ((void*)-1)
130 #endif
132 #define mmap git_mmap
133 #define munmap git_munmap
134 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
135 extern int git_munmap(void *start, size_t length);
137 /* This value must be multiple of (pagesize * 2) */
138 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
140 #else /* NO_MMAP */
142 #include <sys/mman.h>
144 /* This value must be multiple of (pagesize * 2) */
145 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
146 (sizeof(void*) >= 8 \
147 ? 1 * 1024 * 1024 * 1024 \
148 : 32 * 1024 * 1024)
150 #endif /* NO_MMAP */
152 #define DEFAULT_PACKED_GIT_LIMIT \
153 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
155 #ifdef NO_PREAD
156 #define pread git_pread
157 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
158 #endif
160 #ifdef NO_SETENV
161 #define setenv gitsetenv
162 extern int gitsetenv(const char *, const char *, int);
163 #endif
165 #ifdef NO_MKDTEMP
166 #define mkdtemp gitmkdtemp
167 extern char *gitmkdtemp(char *);
168 #endif
170 #ifdef NO_UNSETENV
171 #define unsetenv gitunsetenv
172 extern void gitunsetenv(const char *);
173 #endif
175 #ifdef NO_STRCASESTR
176 #define strcasestr gitstrcasestr
177 extern char *gitstrcasestr(const char *haystack, const char *needle);
178 #endif
180 #ifdef NO_STRLCPY
181 #define strlcpy gitstrlcpy
182 extern size_t gitstrlcpy(char *, const char *, size_t);
183 #endif
185 #ifdef NO_STRTOUMAX
186 #define strtoumax gitstrtoumax
187 extern uintmax_t gitstrtoumax(const char *, char **, int);
188 #endif
190 #ifdef NO_HSTRERROR
191 #define hstrerror githstrerror
192 extern const char *githstrerror(int herror);
193 #endif
195 #ifdef NO_MEMMEM
196 #define memmem gitmemmem
197 void *gitmemmem(const void *haystack, size_t haystacklen,
198 const void *needle, size_t needlelen);
199 #endif
201 #ifdef __GLIBC_PREREQ
202 #if __GLIBC_PREREQ(2, 1)
203 #define HAVE_STRCHRNUL
204 #endif
205 #endif
207 #ifndef HAVE_STRCHRNUL
208 #define strchrnul gitstrchrnul
209 static inline char *gitstrchrnul(const char *s, int c)
211 while (*s && *s != c)
212 s++;
213 return (char *)s;
215 #endif
217 extern void release_pack_memory(size_t, int);
219 static inline char* xstrdup(const char *str)
221 char *ret = strdup(str);
222 if (!ret) {
223 release_pack_memory(strlen(str) + 1, -1);
224 ret = strdup(str);
225 if (!ret)
226 die("Out of memory, strdup failed");
228 return ret;
231 static inline void *xmalloc(size_t size)
233 void *ret = malloc(size);
234 if (!ret && !size)
235 ret = malloc(1);
236 if (!ret) {
237 release_pack_memory(size, -1);
238 ret = malloc(size);
239 if (!ret && !size)
240 ret = malloc(1);
241 if (!ret)
242 die("Out of memory, malloc failed");
244 #ifdef XMALLOC_POISON
245 memset(ret, 0xA5, size);
246 #endif
247 return ret;
250 static inline void *xmemdupz(const void *data, size_t len)
252 char *p = xmalloc(len + 1);
253 memcpy(p, data, len);
254 p[len] = '\0';
255 return p;
258 static inline char *xstrndup(const char *str, size_t len)
260 char *p = memchr(str, '\0', len);
261 return xmemdupz(str, p ? p - str : len);
264 static inline void *xrealloc(void *ptr, size_t size)
266 void *ret = realloc(ptr, size);
267 if (!ret && !size)
268 ret = realloc(ptr, 1);
269 if (!ret) {
270 release_pack_memory(size, -1);
271 ret = realloc(ptr, size);
272 if (!ret && !size)
273 ret = realloc(ptr, 1);
274 if (!ret)
275 die("Out of memory, realloc failed");
277 return ret;
280 static inline void *xcalloc(size_t nmemb, size_t size)
282 void *ret = calloc(nmemb, size);
283 if (!ret && (!nmemb || !size))
284 ret = calloc(1, 1);
285 if (!ret) {
286 release_pack_memory(nmemb * size, -1);
287 ret = calloc(nmemb, size);
288 if (!ret && (!nmemb || !size))
289 ret = calloc(1, 1);
290 if (!ret)
291 die("Out of memory, calloc failed");
293 return ret;
296 static inline void *xmmap(void *start, size_t length,
297 int prot, int flags, int fd, off_t offset)
299 void *ret = mmap(start, length, prot, flags, fd, offset);
300 if (ret == MAP_FAILED) {
301 if (!length)
302 return NULL;
303 release_pack_memory(length, fd);
304 ret = mmap(start, length, prot, flags, fd, offset);
305 if (ret == MAP_FAILED)
306 die("Out of memory? mmap failed: %s", strerror(errno));
308 return ret;
311 static inline ssize_t xread(int fd, void *buf, size_t len)
313 ssize_t nr;
314 while (1) {
315 nr = read(fd, buf, len);
316 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
317 continue;
318 return nr;
322 static inline ssize_t xwrite(int fd, const void *buf, size_t len)
324 ssize_t nr;
325 while (1) {
326 nr = write(fd, buf, len);
327 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
328 continue;
329 return nr;
333 static inline int xdup(int fd)
335 int ret = dup(fd);
336 if (ret < 0)
337 die("dup failed: %s", strerror(errno));
338 return ret;
341 static inline FILE *xfdopen(int fd, const char *mode)
343 FILE *stream = fdopen(fd, mode);
344 if (stream == NULL)
345 die("Out of memory? fdopen failed: %s", strerror(errno));
346 return stream;
349 static inline int xmkstemp(char *template)
351 int fd;
353 fd = mkstemp(template);
354 if (fd < 0)
355 die("Unable to create temporary file: %s", strerror(errno));
356 return fd;
359 static inline size_t xsize_t(off_t len)
361 return (size_t)len;
364 static inline int has_extension(const char *filename, const char *ext)
366 size_t len = strlen(filename);
367 size_t extlen = strlen(ext);
368 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
371 /* Sane ctype - no locale, and works with signed chars */
372 #undef isspace
373 #undef isdigit
374 #undef isalpha
375 #undef isalnum
376 #undef tolower
377 #undef toupper
378 extern unsigned char sane_ctype[256];
379 #define GIT_SPACE 0x01
380 #define GIT_DIGIT 0x02
381 #define GIT_ALPHA 0x04
382 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
383 #define isspace(x) sane_istest(x,GIT_SPACE)
384 #define isdigit(x) sane_istest(x,GIT_DIGIT)
385 #define isalpha(x) sane_istest(x,GIT_ALPHA)
386 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
387 #define tolower(x) sane_case((unsigned char)(x), 0x20)
388 #define toupper(x) sane_case((unsigned char)(x), 0)
390 static inline int sane_case(int x, int high)
392 if (sane_istest(x, GIT_ALPHA))
393 x = (x & ~0x20) | high;
394 return x;
397 static inline int prefixcmp(const char *str, const char *prefix)
399 return strncmp(str, prefix, strlen(prefix));
402 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
404 unsigned long ul;
405 char *p;
407 errno = 0;
408 ul = strtoul(s, &p, base);
409 if (errno || *p || p == s || (unsigned int) ul != ul)
410 return -1;
411 *result = ul;
412 return 0;
415 static inline int strtol_i(char const *s, int base, int *result)
417 long ul;
418 char *p;
420 errno = 0;
421 ul = strtol(s, &p, base);
422 if (errno || *p || p == s || (int) ul != ul)
423 return -1;
424 *result = ul;
425 return 0;
428 #endif