gitweb: Update and improve gitweb/README file
[git/repo.git] / git-compat-util.h
blob79eb10eacba955e0c58a0a540c4ac577f84953e9
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 <sys/ioctl.h>
71 #include <sys/select.h>
72 #include <assert.h>
73 #include <regex.h>
74 #include <netinet/in.h>
75 #include <netinet/tcp.h>
76 #include <arpa/inet.h>
77 #include <netdb.h>
78 #include <pwd.h>
79 #include <inttypes.h>
80 #if defined(__CYGWIN__)
81 #undef _XOPEN_SOURCE
82 #include <grp.h>
83 #define _XOPEN_SOURCE 600
84 #else
85 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
86 #include <grp.h>
87 #define _ALL_SOURCE 1
88 #endif
90 #ifndef NO_ICONV
91 #include <iconv.h>
92 #endif
94 /* On most systems <limits.h> would have given us this, but
95 * not on some systems (e.g. GNU/Hurd).
97 #ifndef PATH_MAX
98 #define PATH_MAX 4096
99 #endif
101 #ifndef PRIuMAX
102 #define PRIuMAX "llu"
103 #endif
105 #ifdef __GNUC__
106 #define NORETURN __attribute__((__noreturn__))
107 #else
108 #define NORETURN
109 #ifndef __attribute__
110 #define __attribute__(x)
111 #endif
112 #endif
114 /* General helper functions */
115 extern void usage(const char *err) NORETURN;
116 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
117 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
118 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
120 extern void set_usage_routine(void (*routine)(const char *err) NORETURN);
121 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
122 extern void set_error_routine(void (*routine)(const char *err, va_list params));
123 extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
125 #ifdef NO_MMAP
127 #ifndef PROT_READ
128 #define PROT_READ 1
129 #define PROT_WRITE 2
130 #define MAP_PRIVATE 1
131 #define MAP_FAILED ((void*)-1)
132 #endif
134 #define mmap git_mmap
135 #define munmap git_munmap
136 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
137 extern int git_munmap(void *start, size_t length);
139 /* This value must be multiple of (pagesize * 2) */
140 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
142 #else /* NO_MMAP */
144 #include <sys/mman.h>
146 /* This value must be multiple of (pagesize * 2) */
147 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
148 (sizeof(void*) >= 8 \
149 ? 1 * 1024 * 1024 * 1024 \
150 : 32 * 1024 * 1024)
152 #endif /* NO_MMAP */
154 #define DEFAULT_PACKED_GIT_LIMIT \
155 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
157 #ifdef NO_PREAD
158 #define pread git_pread
159 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
160 #endif
162 #ifdef NO_SETENV
163 #define setenv gitsetenv
164 extern int gitsetenv(const char *, const char *, int);
165 #endif
167 #ifdef NO_MKDTEMP
168 #define mkdtemp gitmkdtemp
169 extern char *gitmkdtemp(char *);
170 #endif
172 #ifdef NO_UNSETENV
173 #define unsetenv gitunsetenv
174 extern void gitunsetenv(const char *);
175 #endif
177 #ifdef NO_STRCASESTR
178 #define strcasestr gitstrcasestr
179 extern char *gitstrcasestr(const char *haystack, const char *needle);
180 #endif
182 #ifdef NO_STRLCPY
183 #define strlcpy gitstrlcpy
184 extern size_t gitstrlcpy(char *, const char *, size_t);
185 #endif
187 #ifdef NO_STRTOUMAX
188 #define strtoumax gitstrtoumax
189 extern uintmax_t gitstrtoumax(const char *, char **, int);
190 #endif
192 #ifdef NO_HSTRERROR
193 #define hstrerror githstrerror
194 extern const char *githstrerror(int herror);
195 #endif
197 #ifdef NO_MEMMEM
198 #define memmem gitmemmem
199 void *gitmemmem(const void *haystack, size_t haystacklen,
200 const void *needle, size_t needlelen);
201 #endif
203 #ifdef __GLIBC_PREREQ
204 #if __GLIBC_PREREQ(2, 1)
205 #define HAVE_STRCHRNUL
206 #endif
207 #endif
209 #ifndef HAVE_STRCHRNUL
210 #define strchrnul gitstrchrnul
211 static inline char *gitstrchrnul(const char *s, int c)
213 while (*s && *s != c)
214 s++;
215 return (char *)s;
217 #endif
219 extern void release_pack_memory(size_t, int);
221 static inline char* xstrdup(const char *str)
223 char *ret = strdup(str);
224 if (!ret) {
225 release_pack_memory(strlen(str) + 1, -1);
226 ret = strdup(str);
227 if (!ret)
228 die("Out of memory, strdup failed");
230 return ret;
233 static inline void *xmalloc(size_t size)
235 void *ret = malloc(size);
236 if (!ret && !size)
237 ret = malloc(1);
238 if (!ret) {
239 release_pack_memory(size, -1);
240 ret = malloc(size);
241 if (!ret && !size)
242 ret = malloc(1);
243 if (!ret)
244 die("Out of memory, malloc failed");
246 #ifdef XMALLOC_POISON
247 memset(ret, 0xA5, size);
248 #endif
249 return ret;
252 static inline void *xmemdupz(const void *data, size_t len)
254 char *p = xmalloc(len + 1);
255 memcpy(p, data, len);
256 p[len] = '\0';
257 return p;
260 static inline char *xstrndup(const char *str, size_t len)
262 char *p = memchr(str, '\0', len);
263 return xmemdupz(str, p ? p - str : len);
266 static inline void *xrealloc(void *ptr, size_t size)
268 void *ret = realloc(ptr, size);
269 if (!ret && !size)
270 ret = realloc(ptr, 1);
271 if (!ret) {
272 release_pack_memory(size, -1);
273 ret = realloc(ptr, size);
274 if (!ret && !size)
275 ret = realloc(ptr, 1);
276 if (!ret)
277 die("Out of memory, realloc failed");
279 return ret;
282 static inline void *xcalloc(size_t nmemb, size_t size)
284 void *ret = calloc(nmemb, size);
285 if (!ret && (!nmemb || !size))
286 ret = calloc(1, 1);
287 if (!ret) {
288 release_pack_memory(nmemb * size, -1);
289 ret = calloc(nmemb, size);
290 if (!ret && (!nmemb || !size))
291 ret = calloc(1, 1);
292 if (!ret)
293 die("Out of memory, calloc failed");
295 return ret;
298 static inline void *xmmap(void *start, size_t length,
299 int prot, int flags, int fd, off_t offset)
301 void *ret = mmap(start, length, prot, flags, fd, offset);
302 if (ret == MAP_FAILED) {
303 if (!length)
304 return NULL;
305 release_pack_memory(length, fd);
306 ret = mmap(start, length, prot, flags, fd, offset);
307 if (ret == MAP_FAILED)
308 die("Out of memory? mmap failed: %s", strerror(errno));
310 return ret;
313 static inline ssize_t xread(int fd, void *buf, size_t len)
315 ssize_t nr;
316 while (1) {
317 nr = read(fd, buf, len);
318 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
319 continue;
320 return nr;
324 static inline ssize_t xwrite(int fd, const void *buf, size_t len)
326 ssize_t nr;
327 while (1) {
328 nr = write(fd, buf, len);
329 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
330 continue;
331 return nr;
335 static inline int xdup(int fd)
337 int ret = dup(fd);
338 if (ret < 0)
339 die("dup failed: %s", strerror(errno));
340 return ret;
343 static inline FILE *xfdopen(int fd, const char *mode)
345 FILE *stream = fdopen(fd, mode);
346 if (stream == NULL)
347 die("Out of memory? fdopen failed: %s", strerror(errno));
348 return stream;
351 static inline int xmkstemp(char *template)
353 int fd;
355 fd = mkstemp(template);
356 if (fd < 0)
357 die("Unable to create temporary file: %s", strerror(errno));
358 return fd;
361 static inline size_t xsize_t(off_t len)
363 return (size_t)len;
366 static inline int has_extension(const char *filename, const char *ext)
368 size_t len = strlen(filename);
369 size_t extlen = strlen(ext);
370 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
373 /* Sane ctype - no locale, and works with signed chars */
374 #undef isspace
375 #undef isdigit
376 #undef isalpha
377 #undef isalnum
378 #undef tolower
379 #undef toupper
380 extern unsigned char sane_ctype[256];
381 #define GIT_SPACE 0x01
382 #define GIT_DIGIT 0x02
383 #define GIT_ALPHA 0x04
384 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
385 #define isspace(x) sane_istest(x,GIT_SPACE)
386 #define isdigit(x) sane_istest(x,GIT_DIGIT)
387 #define isalpha(x) sane_istest(x,GIT_ALPHA)
388 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
389 #define tolower(x) sane_case((unsigned char)(x), 0x20)
390 #define toupper(x) sane_case((unsigned char)(x), 0)
392 static inline int sane_case(int x, int high)
394 if (sane_istest(x, GIT_ALPHA))
395 x = (x & ~0x20) | high;
396 return x;
399 static inline int prefixcmp(const char *str, const char *prefix)
401 return strncmp(str, prefix, strlen(prefix));
404 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
406 unsigned long ul;
407 char *p;
409 errno = 0;
410 ul = strtoul(s, &p, base);
411 if (errno || *p || p == s || (unsigned int) ul != ul)
412 return -1;
413 *result = ul;
414 return 0;
417 static inline int strtol_i(char const *s, int base, int *result)
419 long ul;
420 char *p;
422 errno = 0;
423 ul = strtol(s, &p, base);
424 if (errno || *p || p == s || (int) ul != ul)
425 return -1;
426 *result = ul;
427 return 0;
430 #endif