Avoid some unnecessary lstat() calls
[git/git-p4.git] / git-compat-util.h
blob01c4045e89a2e156062255193ed5d865fdf8a922
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 <utime.h>
72 #ifndef NO_SYS_SELECT_H
73 #include <sys/select.h>
74 #endif
75 #include <assert.h>
76 #include <regex.h>
77 #include <netinet/in.h>
78 #include <netinet/tcp.h>
79 #include <arpa/inet.h>
80 #include <netdb.h>
81 #include <pwd.h>
82 #include <inttypes.h>
83 #if defined(__CYGWIN__)
84 #undef _XOPEN_SOURCE
85 #include <grp.h>
86 #define _XOPEN_SOURCE 600
87 #else
88 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
89 #include <grp.h>
90 #define _ALL_SOURCE 1
91 #endif
93 #ifndef NO_ICONV
94 #include <iconv.h>
95 #endif
97 /* On most systems <limits.h> would have given us this, but
98 * not on some systems (e.g. GNU/Hurd).
100 #ifndef PATH_MAX
101 #define PATH_MAX 4096
102 #endif
104 #ifndef PRIuMAX
105 #define PRIuMAX "llu"
106 #endif
108 #ifdef __GNUC__
109 #define NORETURN __attribute__((__noreturn__))
110 #else
111 #define NORETURN
112 #ifndef __attribute__
113 #define __attribute__(x)
114 #endif
115 #endif
117 /* General helper functions */
118 extern void usage(const char *err) NORETURN;
119 extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
120 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
121 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
123 extern void set_usage_routine(void (*routine)(const char *err) NORETURN);
124 extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
125 extern void set_error_routine(void (*routine)(const char *err, va_list params));
126 extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
128 extern int prefixcmp(const char *str, const char *prefix);
130 #ifdef NO_MMAP
132 #ifndef PROT_READ
133 #define PROT_READ 1
134 #define PROT_WRITE 2
135 #define MAP_PRIVATE 1
136 #define MAP_FAILED ((void*)-1)
137 #endif
139 #define mmap git_mmap
140 #define munmap git_munmap
141 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
142 extern int git_munmap(void *start, size_t length);
144 /* This value must be multiple of (pagesize * 2) */
145 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
147 #else /* NO_MMAP */
149 #include <sys/mman.h>
151 /* This value must be multiple of (pagesize * 2) */
152 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
153 (sizeof(void*) >= 8 \
154 ? 1 * 1024 * 1024 * 1024 \
155 : 32 * 1024 * 1024)
157 #endif /* NO_MMAP */
159 #define DEFAULT_PACKED_GIT_LIMIT \
160 ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
162 #ifdef NO_PREAD
163 #define pread git_pread
164 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
165 #endif
167 #ifdef NO_SETENV
168 #define setenv gitsetenv
169 extern int gitsetenv(const char *, const char *, int);
170 #endif
172 #ifdef NO_MKDTEMP
173 #define mkdtemp gitmkdtemp
174 extern char *gitmkdtemp(char *);
175 #endif
177 #ifdef NO_UNSETENV
178 #define unsetenv gitunsetenv
179 extern void gitunsetenv(const char *);
180 #endif
182 #ifdef NO_STRCASESTR
183 #define strcasestr gitstrcasestr
184 extern char *gitstrcasestr(const char *haystack, const char *needle);
185 #endif
187 #ifdef NO_STRLCPY
188 #define strlcpy gitstrlcpy
189 extern size_t gitstrlcpy(char *, const char *, size_t);
190 #endif
192 #ifdef NO_STRTOUMAX
193 #define strtoumax gitstrtoumax
194 extern uintmax_t gitstrtoumax(const char *, char **, int);
195 #endif
197 #ifdef NO_HSTRERROR
198 #define hstrerror githstrerror
199 extern const char *githstrerror(int herror);
200 #endif
202 #ifdef NO_MEMMEM
203 #define memmem gitmemmem
204 void *gitmemmem(const void *haystack, size_t haystacklen,
205 const void *needle, size_t needlelen);
206 #endif
208 #ifdef FREAD_READS_DIRECTORIES
209 #ifdef fopen
210 #undef fopen
211 #endif
212 #define fopen(a,b) git_fopen(a,b)
213 extern FILE *git_fopen(const char*, const char*);
214 #endif
216 #ifdef SNPRINTF_RETURNS_BOGUS
217 #define snprintf git_snprintf
218 extern int git_snprintf(char *str, size_t maxsize,
219 const char *format, ...);
220 #define vsnprintf git_vsnprintf
221 extern int git_vsnprintf(char *str, size_t maxsize,
222 const char *format, va_list ap);
223 #endif
225 #ifdef __GLIBC_PREREQ
226 #if __GLIBC_PREREQ(2, 1)
227 #define HAVE_STRCHRNUL
228 #endif
229 #endif
231 #ifndef HAVE_STRCHRNUL
232 #define strchrnul gitstrchrnul
233 static inline char *gitstrchrnul(const char *s, int c)
235 while (*s && *s != c)
236 s++;
237 return (char *)s;
239 #endif
241 extern void release_pack_memory(size_t, int);
243 static inline char* xstrdup(const char *str)
245 char *ret = strdup(str);
246 if (!ret) {
247 release_pack_memory(strlen(str) + 1, -1);
248 ret = strdup(str);
249 if (!ret)
250 die("Out of memory, strdup failed");
252 return ret;
255 static inline void *xmalloc(size_t size)
257 void *ret = malloc(size);
258 if (!ret && !size)
259 ret = malloc(1);
260 if (!ret) {
261 release_pack_memory(size, -1);
262 ret = malloc(size);
263 if (!ret && !size)
264 ret = malloc(1);
265 if (!ret)
266 die("Out of memory, malloc failed");
268 #ifdef XMALLOC_POISON
269 memset(ret, 0xA5, size);
270 #endif
271 return ret;
275 * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of
276 * "data" to the allocated memory, zero terminates the allocated memory,
277 * and returns a pointer to the allocated memory. If the allocation fails,
278 * the program dies.
280 static inline void *xmemdupz(const void *data, size_t len)
282 char *p = xmalloc(len + 1);
283 memcpy(p, data, len);
284 p[len] = '\0';
285 return p;
288 static inline char *xstrndup(const char *str, size_t len)
290 char *p = memchr(str, '\0', len);
291 return xmemdupz(str, p ? p - str : len);
294 static inline void *xrealloc(void *ptr, size_t size)
296 void *ret = realloc(ptr, size);
297 if (!ret && !size)
298 ret = realloc(ptr, 1);
299 if (!ret) {
300 release_pack_memory(size, -1);
301 ret = realloc(ptr, size);
302 if (!ret && !size)
303 ret = realloc(ptr, 1);
304 if (!ret)
305 die("Out of memory, realloc failed");
307 return ret;
310 static inline void *xcalloc(size_t nmemb, size_t size)
312 void *ret = calloc(nmemb, size);
313 if (!ret && (!nmemb || !size))
314 ret = calloc(1, 1);
315 if (!ret) {
316 release_pack_memory(nmemb * size, -1);
317 ret = calloc(nmemb, size);
318 if (!ret && (!nmemb || !size))
319 ret = calloc(1, 1);
320 if (!ret)
321 die("Out of memory, calloc failed");
323 return ret;
326 static inline void *xmmap(void *start, size_t length,
327 int prot, int flags, int fd, off_t offset)
329 void *ret = mmap(start, length, prot, flags, fd, offset);
330 if (ret == MAP_FAILED) {
331 if (!length)
332 return NULL;
333 release_pack_memory(length, fd);
334 ret = mmap(start, length, prot, flags, fd, offset);
335 if (ret == MAP_FAILED)
336 die("Out of memory? mmap failed: %s", strerror(errno));
338 return ret;
342 * xread() is the same a read(), but it automatically restarts read()
343 * operations with a recoverable error (EAGAIN and EINTR). xread()
344 * DOES NOT GUARANTEE that "len" bytes is read even if the data is available.
346 static inline ssize_t xread(int fd, void *buf, size_t len)
348 ssize_t nr;
349 while (1) {
350 nr = read(fd, buf, len);
351 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
352 continue;
353 return nr;
358 * xwrite() is the same a write(), but it automatically restarts write()
359 * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT
360 * GUARANTEE that "len" bytes is written even if the operation is successful.
362 static inline ssize_t xwrite(int fd, const void *buf, size_t len)
364 ssize_t nr;
365 while (1) {
366 nr = write(fd, buf, len);
367 if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
368 continue;
369 return nr;
373 static inline int xdup(int fd)
375 int ret = dup(fd);
376 if (ret < 0)
377 die("dup failed: %s", strerror(errno));
378 return ret;
381 static inline FILE *xfdopen(int fd, const char *mode)
383 FILE *stream = fdopen(fd, mode);
384 if (stream == NULL)
385 die("Out of memory? fdopen failed: %s", strerror(errno));
386 return stream;
389 static inline int xmkstemp(char *template)
391 int fd;
393 fd = mkstemp(template);
394 if (fd < 0)
395 die("Unable to create temporary file: %s", strerror(errno));
396 return fd;
399 static inline size_t xsize_t(off_t len)
401 return (size_t)len;
404 static inline int has_extension(const char *filename, const char *ext)
406 size_t len = strlen(filename);
407 size_t extlen = strlen(ext);
408 return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
411 /* Sane ctype - no locale, and works with signed chars */
412 #undef isspace
413 #undef isdigit
414 #undef isalpha
415 #undef isalnum
416 #undef tolower
417 #undef toupper
418 extern unsigned char sane_ctype[256];
419 #define GIT_SPACE 0x01
420 #define GIT_DIGIT 0x02
421 #define GIT_ALPHA 0x04
422 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
423 #define isspace(x) sane_istest(x,GIT_SPACE)
424 #define isdigit(x) sane_istest(x,GIT_DIGIT)
425 #define isalpha(x) sane_istest(x,GIT_ALPHA)
426 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
427 #define tolower(x) sane_case((unsigned char)(x), 0x20)
428 #define toupper(x) sane_case((unsigned char)(x), 0)
430 static inline int sane_case(int x, int high)
432 if (sane_istest(x, GIT_ALPHA))
433 x = (x & ~0x20) | high;
434 return x;
437 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
439 unsigned long ul;
440 char *p;
442 errno = 0;
443 ul = strtoul(s, &p, base);
444 if (errno || *p || p == s || (unsigned int) ul != ul)
445 return -1;
446 *result = ul;
447 return 0;
450 static inline int strtol_i(char const *s, int base, int *result)
452 long ul;
453 char *p;
455 errno = 0;
456 ul = strtol(s, &p, base);
457 if (errno || *p || p == s || (int) ul != ul)
458 return -1;
459 *result = ul;
460 return 0;
463 #ifdef INTERNAL_QSORT
464 void git_qsort(void *base, size_t nmemb, size_t size,
465 int(*compar)(const void *, const void *));
466 #define qsort git_qsort
467 #endif
469 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
470 # define FORCE_DIR_SET_GID S_ISGID
471 #else
472 # define FORCE_DIR_SET_GID 0
473 #endif
475 #endif