git-compat-util.h

   1 #ifndef GIT_COMPAT_UTIL_H
   2 #define GIT_COMPAT_UTIL_H
   3
   4 #ifdef USE_MSVC_CRTDBG
   5 /*
   6  * For these to work they must appear very early in each
   7  * file -- before most of the standard header files.
   8  */
   9 #include <stdlib.h>
  10 #include <crtdbg.h>
  11 #endif
  12
  13 #define _FILE_OFFSET_BITS 64
  14
  15
  16 /* Derived from Linux "Features Test Macro" header
  17  * Convenience macros to test the versions of gcc (or
  18  * a compatible compiler).
  19  * Use them like this:
  20  *  #if GIT_GNUC_PREREQ (2,8)
  21  *   ... code requiring gcc 2.8 or later ...
  22  *  #endif
  23 */
  24 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  25 # define GIT_GNUC_PREREQ(maj, min) \
  26         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  27 #else
  28  #define GIT_GNUC_PREREQ(maj, min) 0
  29 #endif
  30
  31
  32 #ifndef FLEX_ARRAY
  33 /*
  34  * See if our compiler is known to support flexible array members.
  35  */
  36 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && (!defined(__SUNPRO_C) || (__SUNPRO_C > 0x580))
  37 # define FLEX_ARRAY /* empty */
  38 #elif defined(__GNUC__)
  39 # if (__GNUC__ >= 3)
  40 #  define FLEX_ARRAY /* empty */
  41 # else
  42 #  define FLEX_ARRAY 0 /* older GNU extension */
  43 # endif
  44 #endif
  45
  46 /*
  47  * Otherwise, default to safer but a bit wasteful traditional style
  48  */
  49 #ifndef FLEX_ARRAY
  50 # define FLEX_ARRAY 1
  51 #endif
  52 #endif
  53
  54
  55 /*
  56  * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
  57  * @cond: the compile-time condition which must be true.
  58  *
  59  * Your compile will fail if the condition isn't true, or can't be evaluated
  60  * by the compiler.  This can be used in an expression: its value is "0".
  61  *
  62  * Example:
  63  *      #define foo_to_char(foo)                                        \
  64  *               ((char *)(foo)                                         \
  65  *                + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
  66  */
  67 #define BUILD_ASSERT_OR_ZERO(cond) \
  68         (sizeof(char [1 - 2*!(cond)]) - 1)
  69
  70 #if GIT_GNUC_PREREQ(3, 1)
  71  /* &arr[0] degrades to a pointer: a different type from an array */
  72 # define BARF_UNLESS_AN_ARRAY(arr)                                              \
  73         BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
  74                                                            __typeof__(&(arr)[0])))
  75 #else
  76 # define BARF_UNLESS_AN_ARRAY(arr) 0
  77 #endif
  78 /*
  79  * ARRAY_SIZE - get the number of elements in a visible array
  80  * @x: the array whose size you want.
  81  *
  82  * This does not work on pointers, or arrays declared as [], or
  83  * function parameters.  With correct compiler support, such usage
  84  * will cause a build error (see the build_assert_or_zero macro).
  85  */
  86 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
  87
  88 #define bitsizeof(x)  (CHAR_BIT * sizeof(x))
  89
  90 #define maximum_signed_value_of_type(a) \
  91     (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
  92
  93 #define maximum_unsigned_value_of_type(a) \
  94     (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
  95
  96 /*
  97  * Signed integer overflow is undefined in C, so here's a helper macro
  98  * to detect if the sum of two integers will overflow.
  99  *
 100  * Requires: a >= 0, typeof(a) equals typeof(b)
 101  */
 102 #define signed_add_overflows(a, b) \
 103     ((b) > maximum_signed_value_of_type(a) - (a))
 104
 105 #define unsigned_add_overflows(a, b) \
 106     ((b) > maximum_unsigned_value_of_type(a) - (a))
 107
 108 /*
 109  * Returns true if the multiplication of "a" and "b" will
 110  * overflow. The types of "a" and "b" must match and must be unsigned.
 111  * Note that this macro evaluates "a" twice!
 112  */
 113 #define unsigned_mult_overflows(a, b) \
 114     ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
 115
 116 #ifdef __GNUC__
 117 #define TYPEOF(x) (__typeof__(x))
 118 #else
 119 #define TYPEOF(x)
 120 #endif
 121
 122 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 123 #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 124
 125 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 126
 127 /* Approximation of the length of the decimal representation of this type. */
 128 #define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 129
 130 #if defined(__sun__)
 131  /*
 132   * On Solaris, when _XOPEN_EXTENDED is set, its header file
 133   * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 134   * setting to say we are XPG5 or XPG6.  Also on Solaris,
 135   * XPG6 programs must be compiled with a c99 compiler, while
 136   * non XPG6 programs must be compiled with a pre-c99 compiler.
 137   */
 138 # if __STDC_VERSION__ - 0 >= 199901L
 139 # define _XOPEN_SOURCE 600
 140 # else
 141 # define _XOPEN_SOURCE 500
 142 # endif
 143 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 144       !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 145       !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
 146       !defined(__CYGWIN__)
 147 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 148 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 149 #endif
 150 #define _ALL_SOURCE 1
 151 #define _GNU_SOURCE 1
 152 #define _BSD_SOURCE 1
 153 #define _DEFAULT_SOURCE 1
 154 #define _NETBSD_SOURCE 1
 155 #define _SGI_SOURCE 1
 156
 157 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 158 # if !defined(_WIN32_WINNT)
 159 #  define _WIN32_WINNT 0x0600
 160 # endif
 161 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 162 #include <winsock2.h>
 163 #include <windows.h>
 164 #define GIT_WINDOWS_NATIVE
 165 #endif
 166
 167 #include <unistd.h>
 168 #include <stdio.h>
 169 #include <sys/stat.h>
 170 #include <fcntl.h>
 171 #include <stddef.h>
 172 #include <stdlib.h>
 173 #include <stdarg.h>
 174 #include <string.h>
 175 #ifdef HAVE_STRINGS_H
 176 #include <strings.h> /* for strcasecmp() */
 177 #endif
 178 #include <errno.h>
 179 #include <limits.h>
 180 #ifdef NEEDS_SYS_PARAM_H
 181 #include <sys/param.h>
 182 #endif
 183 #include <sys/types.h>
 184 #include <dirent.h>
 185 #include <sys/time.h>
 186 #include <time.h>
 187 #include <signal.h>
 188 #include <assert.h>
 189 #include <regex.h>
 190 #include <utime.h>
 191 #include <syslog.h>
 192 #if !defined(NO_POLL_H)
 193 #include <poll.h>
 194 #elif !defined(NO_SYS_POLL_H)
 195 #include <sys/poll.h>
 196 #else
 197 /* Pull the compat stuff */
 198 #include <poll.h>
 199 #endif
 200 #ifdef HAVE_BSD_SYSCTL
 201 #include <sys/sysctl.h>
 202 #endif
 203
 204 #if defined(__CYGWIN__)
 205 #include "compat/win32/path-utils.h"
 206 #endif
 207 #if defined(__MINGW32__)
 208 /* pull in Windows compatibility stuff */
 209 #include "compat/win32/path-utils.h"
 210 #include "compat/mingw.h"
 211 #elif defined(_MSC_VER)
 212 #include "compat/win32/path-utils.h"
 213 #include "compat/msvc.h"
 214 #else
 215 #include <sys/utsname.h>
 216 #include <sys/wait.h>
 217 #include <sys/resource.h>
 218 #include <sys/socket.h>
 219 #include <sys/ioctl.h>
 220 #include <termios.h>
 221 #ifndef NO_SYS_SELECT_H
 222 #include <sys/select.h>
 223 #endif
 224 #include <netinet/in.h>
 225 #include <netinet/tcp.h>
 226 #include <arpa/inet.h>
 227 #include <netdb.h>
 228 #include <pwd.h>
 229 #include <sys/un.h>
 230 #ifndef NO_INTTYPES_H
 231 #include <inttypes.h>
 232 #else
 233 #include <stdint.h>
 234 #endif
 235 #ifdef NO_INTPTR_T
 236 /*
 237  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 238  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 239  * while on IP16 and IP16L32 it is "int" (resp. "short")
 240  * Size needs to match (or exceed) 'sizeof(void *)'.
 241  * We can't take "long long" here as not everybody has it.
 242  */
 243 typedef long intptr_t;
 244 typedef unsigned long uintptr_t;
 245 #endif
 246 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 247 #include <grp.h>
 248 #define _ALL_SOURCE 1
 249 #endif
 250
 251 /* used on Mac OS X */
 252 #ifdef PRECOMPOSE_UNICODE
 253 #include "compat/precompose_utf8.h"
 254 #else
 255 #define precompose_str(in,i_nfd2nfc)
 256 #define precompose_argv(c,v)
 257 #define probe_utf8_pathname_composition()
 258 #endif
 259
 260 #ifdef MKDIR_WO_TRAILING_SLASH
 261 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 262 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 263 #endif
 264
 265 #ifdef NO_STRUCT_ITIMERVAL
 266 struct itimerval {
 267         struct timeval it_interval;
 268         struct timeval it_value;
 269 };
 270 #endif
 271
 272 #ifdef NO_SETITIMER
 273 #define setitimer(which,value,ovalue)
 274 #endif
 275
 276 #ifndef NO_LIBGEN_H
 277 #include <libgen.h>
 278 #else
 279 #define basename gitbasename
 280 char *gitbasename(char *);
 281 #define dirname gitdirname
 282 char *gitdirname(char *);
 283 #endif
 284
 285 #ifndef NO_ICONV
 286 #include <iconv.h>
 287 #endif
 288
 289 #ifndef NO_OPENSSL
 290 #ifdef __APPLE__
 291 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 292 #include <AvailabilityMacros.h>
 293 #undef DEPRECATED_ATTRIBUTE
 294 #define DEPRECATED_ATTRIBUTE
 295 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 296 #endif
 297 #include <openssl/ssl.h>
 298 #include <openssl/err.h>
 299 #endif
 300
 301 #ifdef HAVE_SYSINFO
 302 # include <sys/sysinfo.h>
 303 #endif
 304
 305 /* On most systems <netdb.h> would have given us this, but
 306  * not on some systems (e.g. z/OS).
 307  */
 308 #ifndef NI_MAXHOST
 309 #define NI_MAXHOST 1025
 310 #endif
 311
 312 #ifndef NI_MAXSERV
 313 #define NI_MAXSERV 32
 314 #endif
 315
 316 /* On most systems <limits.h> would have given us this, but
 317  * not on some systems (e.g. GNU/Hurd).
 318  */
 319 #ifndef PATH_MAX
 320 #define PATH_MAX 4096
 321 #endif
 322
 323 typedef uintmax_t timestamp_t;
 324 #define PRItime PRIuMAX
 325 #define parse_timestamp strtoumax
 326 #define TIME_MAX UINTMAX_MAX
 327 #define TIME_MIN 0
 328
 329 #ifndef PATH_SEP
 330 #define PATH_SEP ':'
 331 #endif
 332
 333 #ifdef HAVE_PATHS_H
 334 #include <paths.h>
 335 #endif
 336 #ifndef _PATH_DEFPATH
 337 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 338 #endif
 339
 340 #ifndef platform_core_config
 341 static inline int noop_core_config(const char *var, const char *value, void *cb)
 342 {
 343         return 0;
 344 }
 345 #define platform_core_config noop_core_config
 346 #endif
 347
 348 #ifndef has_dos_drive_prefix
 349 static inline int git_has_dos_drive_prefix(const char *path)
 350 {
 351         return 0;
 352 }
 353 #define has_dos_drive_prefix git_has_dos_drive_prefix
 354 #endif
 355
 356 #ifndef skip_dos_drive_prefix
 357 static inline int git_skip_dos_drive_prefix(char **path)
 358 {
 359         return 0;
 360 }
 361 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 362 #endif
 363
 364 #ifndef is_dir_sep
 365 static inline int git_is_dir_sep(int c)
 366 {
 367         return c == '/';
 368 }
 369 #define is_dir_sep git_is_dir_sep
 370 #endif
 371
 372 #ifndef offset_1st_component
 373 static inline int git_offset_1st_component(const char *path)
 374 {
 375         return is_dir_sep(path[0]);
 376 }
 377 #define offset_1st_component git_offset_1st_component
 378 #endif
 379
 380 #ifndef is_valid_path
 381 #define is_valid_path(path) 1
 382 #endif
 383
 384 #ifndef find_last_dir_sep
 385 static inline char *git_find_last_dir_sep(const char *path)
 386 {
 387         return strrchr(path, '/');
 388 }
 389 #define find_last_dir_sep git_find_last_dir_sep
 390 #endif
 391
 392 #ifndef query_user_email
 393 #define query_user_email() NULL
 394 #endif
 395
 396 #ifdef __TANDEM
 397 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 398 #include <floss.h(floss_getpwuid)>
 399 #ifndef NSIG
 400 /*
 401  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 402  * known, by detective work using kill -l as a list is all signals
 403  * instead of signal.h where it should be.
 404  */
 405 # define NSIG 100
 406 #endif
 407 #endif
 408
 409 #if defined(__HP_cc) && (__HP_cc >= 61000)
 410 #define NORETURN __attribute__((noreturn))
 411 #define NORETURN_PTR
 412 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 413 #define NORETURN __attribute__((__noreturn__))
 414 #define NORETURN_PTR __attribute__((__noreturn__))
 415 #elif defined(_MSC_VER)
 416 #define NORETURN __declspec(noreturn)
 417 #define NORETURN_PTR
 418 #else
 419 #define NORETURN
 420 #define NORETURN_PTR
 421 #ifndef __GNUC__
 422 #ifndef __attribute__
 423 #define __attribute__(x)
 424 #endif
 425 #endif
 426 #endif
 427
 428 /* The sentinel attribute is valid from gcc version 4.0 */
 429 #if defined(__GNUC__) && (__GNUC__ >= 4)
 430 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 431 #else
 432 #define LAST_ARG_MUST_BE_NULL
 433 #endif
 434
 435 #define MAYBE_UNUSED __attribute__((__unused__))
 436
 437 #include "compat/bswap.h"
 438
 439 #include "wildmatch.h"
 440
 441 struct strbuf;
 442
 443 /* General helper functions */
 444 void vreportf(const char *prefix, const char *err, va_list params);
 445 NORETURN void usage(const char *err);
 446 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 447 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 448 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 449 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 450 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 451 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 452 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 453
 454 #ifndef NO_OPENSSL
 455 #ifdef APPLE_COMMON_CRYPTO
 456 #include "compat/apple-common-crypto.h"
 457 #else
 458 #include <openssl/evp.h>
 459 #include <openssl/hmac.h>
 460 #endif /* APPLE_COMMON_CRYPTO */
 461 #include <openssl/x509v3.h>
 462 #endif /* NO_OPENSSL */
 463
 464 /*
 465  * Let callers be aware of the constant return value; this can help
 466  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 467  * because some compilers may not support variadic macros. Since we're only
 468  * trying to help gcc, anyway, it's OK; other compilers will fall back to
 469  * using the function as usual.
 470  */
 471 #if defined(__GNUC__)
 472 static inline int const_error(void)
 473 {
 474         return -1;
 475 }
 476 #define error(...) (error(__VA_ARGS__), const_error())
 477 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 478 #endif
 479
 480 void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 481 void set_error_routine(void (*routine)(const char *err, va_list params));
 482 extern void (*get_error_routine(void))(const char *err, va_list params);
 483 void set_warn_routine(void (*routine)(const char *warn, va_list params));
 484 extern void (*get_warn_routine(void))(const char *warn, va_list params);
 485 void set_die_is_recursing_routine(int (*routine)(void));
 486
 487 int starts_with(const char *str, const char *prefix);
 488 int istarts_with(const char *str, const char *prefix);
 489
 490 /*
 491  * If the string "str" begins with the string found in "prefix", return 1.
 492  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 493  * the string right after the prefix).
 494  *
 495  * Otherwise, return 0 and leave "out" untouched.
 496  *
 497  * Examples:
 498  *
 499  *   [extract branch name, fail if not a branch]
 500  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 501  *      return -1;
 502  *
 503  *   [skip prefix if present, otherwise use whole string]
 504  *   skip_prefix(name, "refs/heads/", &name);
 505  */
 506 static inline int skip_prefix(const char *str, const char *prefix,
 507                               const char **out)
 508 {
 509         do {
 510                 if (!*prefix) {
 511                         *out = str;
 512                         return 1;
 513                 }
 514         } while (*str++ == *prefix++);
 515         return 0;
 516 }
 517
 518 /*
 519  * If the string "str" is the same as the string in "prefix", then the "arg"
 520  * parameter is set to the "def" parameter and 1 is returned.
 521  * If the string "str" begins with the string found in "prefix" and then a
 522  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 523  * (i.e., to the point in the string right after the prefix and the "=" sign),
 524  * and 1 is returned.
 525  *
 526  * Otherwise, return 0 and leave "arg" untouched.
 527  *
 528  * When we accept both a "--key" and a "--key=<val>" option, this function
 529  * can be used instead of !strcmp(arg, "--key") and then
 530  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 531  */
 532 int skip_to_optional_arg_default(const char *str, const char *prefix,
 533                                  const char **arg, const char *def);
 534
 535 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 536                                        const char **arg)
 537 {
 538         return skip_to_optional_arg_default(str, prefix, arg, "");
 539 }
 540
 541 /*
 542  * Like skip_prefix, but promises never to read past "len" bytes of the input
 543  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 544  */
 545 static inline int skip_prefix_mem(const char *buf, size_t len,
 546                                   const char *prefix,
 547                                   const char **out, size_t *outlen)
 548 {
 549         size_t prefix_len = strlen(prefix);
 550         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 551                 *out = buf + prefix_len;
 552                 *outlen = len - prefix_len;
 553                 return 1;
 554         }
 555         return 0;
 556 }
 557
 558 /*
 559  * If buf ends with suffix, return 1 and subtract the length of the suffix
 560  * from *len. Otherwise, return 0 and leave *len untouched.
 561  */
 562 static inline int strip_suffix_mem(const char *buf, size_t *len,
 563                                    const char *suffix)
 564 {
 565         size_t suflen = strlen(suffix);
 566         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 567                 return 0;
 568         *len -= suflen;
 569         return 1;
 570 }
 571
 572 /*
 573  * If str ends with suffix, return 1 and set *len to the size of the string
 574  * without the suffix. Otherwise, return 0 and set *len to the size of the
 575  * string.
 576  *
 577  * Note that we do _not_ NUL-terminate str to the new length.
 578  */
 579 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 580 {
 581         *len = strlen(str);
 582         return strip_suffix_mem(str, len, suffix);
 583 }
 584
 585 static inline int ends_with(const char *str, const char *suffix)
 586 {
 587         size_t len;
 588         return strip_suffix(str, suffix, &len);
 589 }
 590
 591 #define SWAP(a, b) do {                                         \
 592         void *_swap_a_ptr = &(a);                               \
 593         void *_swap_b_ptr = &(b);                               \
 594         unsigned char _swap_buffer[sizeof(a)];                  \
 595         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 596         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 597                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 598         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 599 } while (0)
 600
 601 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 602
 603 #ifndef PROT_READ
 604 #define PROT_READ 1
 605 #define PROT_WRITE 2
 606 #define MAP_PRIVATE 1
 607 #endif
 608
 609 #define mmap git_mmap
 610 #define munmap git_munmap
 611 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 612 int git_munmap(void *start, size_t length);
 613
 614 #else /* NO_MMAP || USE_WIN32_MMAP */
 615
 616 #include <sys/mman.h>
 617
 618 #endif /* NO_MMAP || USE_WIN32_MMAP */
 619
 620 #ifdef NO_MMAP
 621
 622 /* This value must be multiple of (pagesize * 2) */
 623 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 624
 625 #else /* NO_MMAP */
 626
 627 /* This value must be multiple of (pagesize * 2) */
 628 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 629         (sizeof(void*) >= 8 \
 630                 ?  1 * 1024 * 1024 * 1024 \
 631                 : 32 * 1024 * 1024)
 632
 633 #endif /* NO_MMAP */
 634
 635 #ifndef MAP_FAILED
 636 #define MAP_FAILED ((void *)-1)
 637 #endif
 638
 639 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 640 #define on_disk_bytes(st) ((st).st_size)
 641 #else
 642 #define on_disk_bytes(st) ((st).st_blocks * 512)
 643 #endif
 644
 645 #ifdef NEEDS_MODE_TRANSLATION
 646 #undef S_IFMT
 647 #undef S_IFREG
 648 #undef S_IFDIR
 649 #undef S_IFLNK
 650 #undef S_IFBLK
 651 #undef S_IFCHR
 652 #undef S_IFIFO
 653 #undef S_IFSOCK
 654 #define S_IFMT   0170000
 655 #define S_IFREG  0100000
 656 #define S_IFDIR  0040000
 657 #define S_IFLNK  0120000
 658 #define S_IFBLK  0060000
 659 #define S_IFCHR  0020000
 660 #define S_IFIFO  0010000
 661 #define S_IFSOCK 0140000
 662 #ifdef stat
 663 #undef stat
 664 #endif
 665 #define stat(path, buf) git_stat(path, buf)
 666 int git_stat(const char *, struct stat *);
 667 #ifdef fstat
 668 #undef fstat
 669 #endif
 670 #define fstat(fd, buf) git_fstat(fd, buf)
 671 int git_fstat(int, struct stat *);
 672 #ifdef lstat
 673 #undef lstat
 674 #endif
 675 #define lstat(path, buf) git_lstat(path, buf)
 676 int git_lstat(const char *, struct stat *);
 677 #endif
 678
 679 #define DEFAULT_PACKED_GIT_LIMIT \
 680         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 681
 682 #ifdef NO_PREAD
 683 #define pread git_pread
 684 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 685 #endif
 686 /*
 687  * Forward decl that will remind us if its twin in cache.h changes.
 688  * This function is used in compat/pread.c.  But we can't include
 689  * cache.h there.
 690  */
 691 ssize_t read_in_full(int fd, void *buf, size_t count);
 692
 693 #ifdef NO_SETENV
 694 #define setenv gitsetenv
 695 int gitsetenv(const char *, const char *, int);
 696 #endif
 697
 698 #ifdef NO_MKDTEMP
 699 #define mkdtemp gitmkdtemp
 700 char *gitmkdtemp(char *);
 701 #endif
 702
 703 #ifdef NO_UNSETENV
 704 #define unsetenv gitunsetenv
 705 void gitunsetenv(const char *);
 706 #endif
 707
 708 #ifdef NO_STRCASESTR
 709 #define strcasestr gitstrcasestr
 710 char *gitstrcasestr(const char *haystack, const char *needle);
 711 #endif
 712
 713 #ifdef NO_STRLCPY
 714 #define strlcpy gitstrlcpy
 715 size_t gitstrlcpy(char *, const char *, size_t);
 716 #endif
 717
 718 #ifdef NO_STRTOUMAX
 719 #define strtoumax gitstrtoumax
 720 uintmax_t gitstrtoumax(const char *, char **, int);
 721 #define strtoimax gitstrtoimax
 722 intmax_t gitstrtoimax(const char *, char **, int);
 723 #endif
 724
 725 #ifdef NO_HSTRERROR
 726 #define hstrerror githstrerror
 727 const char *githstrerror(int herror);
 728 #endif
 729
 730 #ifdef NO_MEMMEM
 731 #define memmem gitmemmem
 732 void *gitmemmem(const void *haystack, size_t haystacklen,
 733                 const void *needle, size_t needlelen);
 734 #endif
 735
 736 #ifdef OVERRIDE_STRDUP
 737 #ifdef strdup
 738 #undef strdup
 739 #endif
 740 #define strdup gitstrdup
 741 char *gitstrdup(const char *s);
 742 #endif
 743
 744 #ifdef NO_GETPAGESIZE
 745 #define getpagesize() sysconf(_SC_PAGESIZE)
 746 #endif
 747
 748 #ifndef O_CLOEXEC
 749 #define O_CLOEXEC 0
 750 #endif
 751
 752 #ifdef FREAD_READS_DIRECTORIES
 753 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 754 #  ifdef fopen
 755 #   undef fopen
 756 #  endif
 757 #  define fopen(a,b) git_fopen(a,b)
 758 # endif
 759 FILE *git_fopen(const char*, const char*);
 760 #endif
 761
 762 #ifdef SNPRINTF_RETURNS_BOGUS
 763 #ifdef snprintf
 764 #undef snprintf
 765 #endif
 766 #define snprintf git_snprintf
 767 int git_snprintf(char *str, size_t maxsize,
 768                  const char *format, ...);
 769 #ifdef vsnprintf
 770 #undef vsnprintf
 771 #endif
 772 #define vsnprintf git_vsnprintf
 773 int git_vsnprintf(char *str, size_t maxsize,
 774                   const char *format, va_list ap);
 775 #endif
 776
 777 #ifdef __GLIBC_PREREQ
 778 #if __GLIBC_PREREQ(2, 1)
 779 #define HAVE_STRCHRNUL
 780 #endif
 781 #endif
 782
 783 #ifndef HAVE_STRCHRNUL
 784 #define strchrnul gitstrchrnul
 785 static inline char *gitstrchrnul(const char *s, int c)
 786 {
 787         while (*s && *s != c)
 788                 s++;
 789         return (char *)s;
 790 }
 791 #endif
 792
 793 #ifdef NO_INET_PTON
 794 int inet_pton(int af, const char *src, void *dst);
 795 #endif
 796
 797 #ifdef NO_INET_NTOP
 798 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 799 #endif
 800
 801 #ifdef NO_PTHREADS
 802 #define atexit git_atexit
 803 int git_atexit(void (*handler)(void));
 804 #endif
 805
 806 static inline size_t st_add(size_t a, size_t b)
 807 {
 808         if (unsigned_add_overflows(a, b))
 809                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 810                     (uintmax_t)a, (uintmax_t)b);
 811         return a + b;
 812 }
 813 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 814 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 815
 816 static inline size_t st_mult(size_t a, size_t b)
 817 {
 818         if (unsigned_mult_overflows(a, b))
 819                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 820                     (uintmax_t)a, (uintmax_t)b);
 821         return a * b;
 822 }
 823
 824 static inline size_t st_sub(size_t a, size_t b)
 825 {
 826         if (a < b)
 827                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 828                     (uintmax_t)a, (uintmax_t)b);
 829         return a - b;
 830 }
 831
 832 #ifdef HAVE_ALLOCA_H
 833 # include <alloca.h>
 834 # define xalloca(size)      (alloca(size))
 835 # define xalloca_free(p)    do {} while (0)
 836 #else
 837 # define xalloca(size)      (xmalloc(size))
 838 # define xalloca_free(p)    (free(p))
 839 #endif
 840 char *xstrdup(const char *str);
 841 void *xmalloc(size_t size);
 842 void *xmallocz(size_t size);
 843 void *xmallocz_gently(size_t size);
 844 void *xmemdupz(const void *data, size_t len);
 845 char *xstrndup(const char *str, size_t len);
 846 void *xrealloc(void *ptr, size_t size);
 847 void *xcalloc(size_t nmemb, size_t size);
 848 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 849 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 850 int xopen(const char *path, int flags, ...);
 851 ssize_t xread(int fd, void *buf, size_t len);
 852 ssize_t xwrite(int fd, const void *buf, size_t len);
 853 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 854 int xdup(int fd);
 855 FILE *xfopen(const char *path, const char *mode);
 856 FILE *xfdopen(int fd, const char *mode);
 857 int xmkstemp(char *temp_filename);
 858 int xmkstemp_mode(char *temp_filename, int mode);
 859 char *xgetcwd(void);
 860 FILE *fopen_for_writing(const char *path);
 861 FILE *fopen_or_warn(const char *path, const char *mode);
 862
 863 /*
 864  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 865  * that ptr is used twice, so don't pass e.g. ptr++.
 866  */
 867 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 868
 869 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 870 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)));
 871 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 872
 873 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 874         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 875 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 876 {
 877         if (n)
 878                 memcpy(dst, src, st_mult(size, n));
 879 }
 880
 881 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
 882         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 883 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
 884 {
 885         if (n)
 886                 memmove(dst, src, st_mult(size, n));
 887 }
 888
 889 /*
 890  * These functions help you allocate structs with flex arrays, and copy
 891  * the data directly into the array. For example, if you had:
 892  *
 893  *   struct foo {
 894  *     int bar;
 895  *     char name[FLEX_ARRAY];
 896  *   };
 897  *
 898  * you can do:
 899  *
 900  *   struct foo *f;
 901  *   FLEX_ALLOC_MEM(f, name, src, len);
 902  *
 903  * to allocate a "foo" with the contents of "src" in the "name" field.
 904  * The resulting struct is automatically zero'd, and the flex-array field
 905  * is NUL-terminated (whether the incoming src buffer was or not).
 906  *
 907  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
 908  * but do want to store a pointer to some extra data in the same allocated
 909  * block. For example, if you have:
 910  *
 911  *   struct foo {
 912  *     char *name;
 913  *     int bar;
 914  *   };
 915  *
 916  * you can do:
 917  *
 918  *   struct foo *f;
 919  *   FLEXPTR_ALLOC_STR(f, name, src);
 920  *
 921  * and "name" will point to a block of memory after the struct, which will be
 922  * freed along with the struct (but the pointer can be repointed anywhere).
 923  *
 924  * The *_STR variants accept a string parameter rather than a ptr/len
 925  * combination.
 926  *
 927  * Note that these macros will evaluate the first parameter multiple
 928  * times, and it must be assignable as an lvalue.
 929  */
 930 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
 931         size_t flex_array_len_ = (len); \
 932         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 933         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
 934 } while (0)
 935 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
 936         size_t flex_array_len_ = (len); \
 937         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 938         memcpy((x) + 1, (buf), flex_array_len_); \
 939         (x)->ptrname = (void *)((x)+1); \
 940 } while(0)
 941 #define FLEX_ALLOC_STR(x, flexname, str) \
 942         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
 943 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
 944         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
 945
 946 static inline char *xstrdup_or_null(const char *str)
 947 {
 948         return str ? xstrdup(str) : NULL;
 949 }
 950
 951 static inline size_t xsize_t(off_t len)
 952 {
 953         size_t size = (size_t) len;
 954
 955         if (len != (off_t) size)
 956                 die("Cannot handle files this big");
 957         return size;
 958 }
 959
 960 __attribute__((format (printf, 3, 4)))
 961 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
 962
 963 #ifndef HOST_NAME_MAX
 964 #define HOST_NAME_MAX 256
 965 #endif
 966
 967 int xgethostname(char *buf, size_t len);
 968
 969 /* in ctype.c, for kwset users */
 970 extern const unsigned char tolower_trans_tbl[256];
 971
 972 /* Sane ctype - no locale, and works with signed chars */
 973 #undef isascii
 974 #undef isspace
 975 #undef isdigit
 976 #undef isalpha
 977 #undef isalnum
 978 #undef isprint
 979 #undef islower
 980 #undef isupper
 981 #undef tolower
 982 #undef toupper
 983 #undef iscntrl
 984 #undef ispunct
 985 #undef isxdigit
 986
 987 extern const unsigned char sane_ctype[256];
 988 #define GIT_SPACE 0x01
 989 #define GIT_DIGIT 0x02
 990 #define GIT_ALPHA 0x04
 991 #define GIT_GLOB_SPECIAL 0x08
 992 #define GIT_REGEX_SPECIAL 0x10
 993 #define GIT_PATHSPEC_MAGIC 0x20
 994 #define GIT_CNTRL 0x40
 995 #define GIT_PUNCT 0x80
 996 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 997 #define isascii(x) (((x) & ~0x7f) == 0)
 998 #define isspace(x) sane_istest(x,GIT_SPACE)
 999 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1000 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1001 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1002 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1003 #define islower(x) sane_iscase(x, 1)
1004 #define isupper(x) sane_iscase(x, 0)
1005 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1006 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1007 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1008 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1009                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1010 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1011 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1012 #define toupper(x) sane_case((unsigned char)(x), 0)
1013 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1014
1015 static inline int sane_case(int x, int high)
1016 {
1017         if (sane_istest(x, GIT_ALPHA))
1018                 x = (x & ~0x20) | high;
1019         return x;
1020 }
1021
1022 static inline int sane_iscase(int x, int is_lower)
1023 {
1024         if (!sane_istest(x, GIT_ALPHA))
1025                 return 0;
1026
1027         if (is_lower)
1028                 return (x & 0x20) != 0;
1029         else
1030                 return (x & 0x20) == 0;
1031 }
1032
1033 /*
1034  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1035  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1036  * locale-specific conversions).
1037  */
1038 static inline int skip_iprefix(const char *str, const char *prefix,
1039                                const char **out)
1040 {
1041         do {
1042                 if (!*prefix) {
1043                         *out = str;
1044                         return 1;
1045                 }
1046         } while (tolower(*str++) == tolower(*prefix++));
1047         return 0;
1048 }
1049
1050 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1051 {
1052         unsigned long ul;
1053         char *p;
1054
1055         errno = 0;
1056         /* negative values would be accepted by strtoul */
1057         if (strchr(s, '-'))
1058                 return -1;
1059         ul = strtoul(s, &p, base);
1060         if (errno || *p || p == s || (unsigned int) ul != ul)
1061                 return -1;
1062         *result = ul;
1063         return 0;
1064 }
1065
1066 static inline int strtol_i(char const *s, int base, int *result)
1067 {
1068         long ul;
1069         char *p;
1070
1071         errno = 0;
1072         ul = strtol(s, &p, base);
1073         if (errno || *p || p == s || (int) ul != ul)
1074                 return -1;
1075         *result = ul;
1076         return 0;
1077 }
1078
1079 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1080                       int(*compar)(const void *, const void *));
1081 #ifdef INTERNAL_QSORT
1082 #define qsort git_stable_qsort
1083 #endif
1084
1085 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1086 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1087                               int(*compar)(const void *, const void *))
1088 {
1089         if (nmemb > 1)
1090                 qsort(base, nmemb, size, compar);
1091 }
1092
1093 #define STABLE_QSORT(base, n, compar) \
1094         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1095
1096 #ifndef HAVE_ISO_QSORT_S
1097 int git_qsort_s(void *base, size_t nmemb, size_t size,
1098                 int (*compar)(const void *, const void *, void *), void *ctx);
1099 #define qsort_s git_qsort_s
1100 #endif
1101
1102 #define QSORT_S(base, n, compar, ctx) do {                      \
1103         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1104                 BUG("qsort_s() failed");                        \
1105 } while (0)
1106
1107 #ifndef REG_STARTEND
1108 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1109 #endif
1110
1111 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1112                               size_t nmatch, regmatch_t pmatch[], int eflags)
1113 {
1114         assert(nmatch > 0 && pmatch);
1115         pmatch[0].rm_so = 0;
1116         pmatch[0].rm_eo = size;
1117         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1118 }
1119
1120 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1121 # define FORCE_DIR_SET_GID S_ISGID
1122 #else
1123 # define FORCE_DIR_SET_GID 0
1124 #endif
1125
1126 #ifdef NO_NSEC
1127 #undef USE_NSEC
1128 #define ST_CTIME_NSEC(st) 0
1129 #define ST_MTIME_NSEC(st) 0
1130 #else
1131 #ifdef USE_ST_TIMESPEC
1132 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1133 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1134 #else
1135 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1136 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1137 #endif
1138 #endif
1139
1140 #ifdef UNRELIABLE_FSTAT
1141 #define fstat_is_reliable() 0
1142 #else
1143 #define fstat_is_reliable() 1
1144 #endif
1145
1146 #ifndef va_copy
1147 /*
1148  * Since an obvious implementation of va_list would be to make it a
1149  * pointer into the stack frame, a simple assignment will work on
1150  * many systems.  But let's try to be more portable.
1151  */
1152 #ifdef __va_copy
1153 #define va_copy(dst, src) __va_copy(dst, src)
1154 #else
1155 #define va_copy(dst, src) ((dst) = (src))
1156 #endif
1157 #endif
1158
1159 #if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
1160 #define HAVE_VARIADIC_MACROS 1
1161 #endif
1162
1163 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1164 extern int BUG_exit_code;
1165
1166 #ifdef HAVE_VARIADIC_MACROS
1167 __attribute__((format (printf, 3, 4))) NORETURN
1168 void BUG_fl(const char *file, int line, const char *fmt, ...);
1169 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1170 #else
1171 __attribute__((format (printf, 1, 2))) NORETURN
1172 void BUG(const char *fmt, ...);
1173 #endif
1174
1175 /*
1176  * Preserves errno, prints a message, but gives no warning for ENOENT.
1177  * Returns 0 on success, which includes trying to unlink an object that does
1178  * not exist.
1179  */
1180 int unlink_or_warn(const char *path);
1181  /*
1182   * Tries to unlink file.  Returns 0 if unlink succeeded
1183   * or the file already didn't exist.  Returns -1 and
1184   * appends a message to err suitable for
1185   * 'error("%s", err->buf)' on error.
1186   */
1187 int unlink_or_msg(const char *file, struct strbuf *err);
1188 /*
1189  * Preserves errno, prints a message, but gives no warning for ENOENT.
1190  * Returns 0 on success, which includes trying to remove a directory that does
1191  * not exist.
1192  */
1193 int rmdir_or_warn(const char *path);
1194 /*
1195  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1196  * the supplied file mode.
1197  */
1198 int remove_or_warn(unsigned int mode, const char *path);
1199
1200 /*
1201  * Call access(2), but warn for any error except "missing file"
1202  * (ENOENT or ENOTDIR).
1203  */
1204 #define ACCESS_EACCES_OK (1U << 0)
1205 int access_or_warn(const char *path, int mode, unsigned flag);
1206 int access_or_die(const char *path, int mode, unsigned flag);
1207
1208 /* Warn on an inaccessible file if errno indicates this is an error */
1209 int warn_on_fopen_errors(const char *path);
1210
1211 #ifdef GMTIME_UNRELIABLE_ERRORS
1212 struct tm *git_gmtime(const time_t *);
1213 struct tm *git_gmtime_r(const time_t *, struct tm *);
1214 #define gmtime git_gmtime
1215 #define gmtime_r git_gmtime_r
1216 #endif
1217
1218 #if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1219 #define USE_PARENS_AROUND_GETTEXT_N 1
1220 #endif
1221
1222 #ifndef SHELL_PATH
1223 # define SHELL_PATH "/bin/sh"
1224 #endif
1225
1226 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1227 #define flockfile(fh)
1228 #define funlockfile(fh)
1229 #define getc_unlocked(fh) getc(fh)
1230 #endif
1231
1232 #ifdef FILENO_IS_A_MACRO
1233 int git_fileno(FILE *stream);
1234 # ifndef COMPAT_CODE_FILENO
1235 #  undef fileno
1236 #  define fileno(p) git_fileno(p)
1237 # endif
1238 #endif
1239
1240 #ifdef NEED_ACCESS_ROOT_HANDLER
1241 int git_access(const char *path, int mode);
1242 # ifndef COMPAT_CODE_ACCESS
1243 #  ifdef access
1244 #  undef access
1245 #  endif
1246 #  define access(path, mode) git_access(path, mode)
1247 # endif
1248 #endif
1249
1250 /*
1251  * Our code often opens a path to an optional file, to work on its
1252  * contents when we can successfully open it.  We can ignore a failure
1253  * to open if such an optional file does not exist, but we do want to
1254  * report a failure in opening for other reasons (e.g. we got an I/O
1255  * error, or the file is there, but we lack the permission to open).
1256  *
1257  * Call this function after seeing an error from open() or fopen() to
1258  * see if the errno indicates a missing file that we can safely ignore.
1259  */
1260 static inline int is_missing_file_error(int errno_)
1261 {
1262         return (errno_ == ENOENT || errno_ == ENOTDIR);
1263 }
1264
1265 int cmd_main(int, const char **);
1266
1267 /*
1268  * Intercept all calls to exit() and route them to trace2 to
1269  * optionally emit a message before calling the real exit().
1270  */
1271 int trace2_cmd_exit_fl(const char *file, int line, int code);
1272 #define exit(code) exit(trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
1273
1274 /*
1275  * You can mark a stack variable with UNLEAK(var) to avoid it being
1276  * reported as a leak by tools like LSAN or valgrind. The argument
1277  * should generally be the variable itself (not its address and not what
1278  * it points to). It's safe to use this on pointers which may already
1279  * have been freed, or on pointers which may still be in use.
1280  *
1281  * Use this _only_ for a variable that leaks by going out of scope at
1282  * program exit (so only from cmd_* functions or their direct helpers).
1283  * Normal functions, especially those which may be called multiple
1284  * times, should actually free their memory. This is only meant as
1285  * an annotation, and does nothing in non-leak-checking builds.
1286  */
1287 #ifdef SUPPRESS_ANNOTATED_LEAKS
1288 void unleak_memory(const void *ptr, size_t len);
1289 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1290 #else
1291 #define UNLEAK(var) do {} while (0)
1292 #endif
1293
1294 /*
1295  * This include must come after system headers, since it introduces macros that
1296  * replace system names.
1297  */
1298 #include "banned.h"
1299
1300 /*
1301  * container_of - Get the address of an object containing a field.
1302  *
1303  * @ptr: pointer to the field.
1304  * @type: type of the object.
1305  * @member: name of the field within the object.
1306  */
1307 #define container_of(ptr, type, member) \
1308         ((type *) ((char *)(ptr) - offsetof(type, member)))
1309
1310 /*
1311  * helper function for `container_of_or_null' to avoid multiple
1312  * evaluation of @ptr
1313  */
1314 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1315 {
1316         return ptr ? (char *)ptr - offset : NULL;
1317 }
1318
1319 /*
1320  * like `container_of', but allows returned value to be NULL
1321  */
1322 #define container_of_or_null(ptr, type, member) \
1323         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1324
1325 /*
1326  * like offsetof(), but takes a pointer to a a variable of type which
1327  * contains @member, instead of a specified type.
1328  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1329  * everywhere.
1330  */
1331 #if defined(__GNUC__) /* clang sets this, too */
1332 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1333 #else /* !__GNUC__ */
1334 #define OFFSETOF_VAR(ptr, member) \
1335         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1336 #endif /* !__GNUC__ */
1337
1338 #endif