git-compat-util.h

   1 #ifndef GIT_COMPAT_UTIL_H
   2 #define GIT_COMPAT_UTIL_H
   3
   4 #if __STDC_VERSION__ - 0 < 199901L
   5 /*
   6  * Git is in a testing period for mandatory C99 support in the compiler.  If
   7  * your compiler is reasonably recent, you can try to enable C99 support (or,
   8  * for MSVC, C11 support).  If you encounter a problem and can't enable C99
   9  * support with your compiler (such as with "-std=gnu99") and don't have access
  10  * to one with this support, such as GCC or Clang, you can remove this #if
  11  * directive, but please report the details of your system to
  12  * git@vger.kernel.org.
  13  */
  14 #error "Required C99 support is in a test phase.  Please see git-compat-util.h for more details."
  15 #endif
  16
  17 #ifdef USE_MSVC_CRTDBG
  18 /*
  19  * For these to work they must appear very early in each
  20  * file -- before most of the standard header files.
  21  */
  22 #include <stdlib.h>
  23 #include <crtdbg.h>
  24 #endif
  25
  26 #define _FILE_OFFSET_BITS 64
  27
  28
  29 /* Derived from Linux "Features Test Macro" header
  30  * Convenience macros to test the versions of gcc (or
  31  * a compatible compiler).
  32  * Use them like this:
  33  *  #if GIT_GNUC_PREREQ (2,8)
  34  *   ... code requiring gcc 2.8 or later ...
  35  *  #endif
  36 */
  37 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  38 # define GIT_GNUC_PREREQ(maj, min) \
  39         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  40 #else
  41  #define GIT_GNUC_PREREQ(maj, min) 0
  42 #endif
  43
  44
  45 #ifndef FLEX_ARRAY
  46 /*
  47  * See if our compiler is known to support flexible array members.
  48  */
  49
  50 /*
  51  * Check vendor specific quirks first, before checking the
  52  * __STDC_VERSION__, as vendor compilers can lie and we need to be
  53  * able to work them around.  Note that by not defining FLEX_ARRAY
  54  * here, we can fall back to use the "safer but a bit wasteful" one
  55  * later.
  56  */
  57 #if defined(__SUNPRO_C) && (__SUNPRO_C <= 0x580)
  58 #elif defined(__GNUC__)
  59 # if (__GNUC__ >= 3)
  60 #  define FLEX_ARRAY /* empty */
  61 # else
  62 #  define FLEX_ARRAY 0 /* older GNU extension */
  63 # endif
  64 #elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
  65 # define FLEX_ARRAY /* empty */
  66 #endif
  67
  68 /*
  69  * Otherwise, default to safer but a bit wasteful traditional style
  70  */
  71 #ifndef FLEX_ARRAY
  72 # define FLEX_ARRAY 1
  73 #endif
  74 #endif
  75
  76
  77 /*
  78  * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
  79  * @cond: the compile-time condition which must be true.
  80  *
  81  * Your compile will fail if the condition isn't true, or can't be evaluated
  82  * by the compiler.  This can be used in an expression: its value is "0".
  83  *
  84  * Example:
  85  *      #define foo_to_char(foo)                                        \
  86  *               ((char *)(foo)                                         \
  87  *                + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
  88  */
  89 #define BUILD_ASSERT_OR_ZERO(cond) \
  90         (sizeof(char [1 - 2*!(cond)]) - 1)
  91
  92 #if GIT_GNUC_PREREQ(3, 1)
  93  /* &arr[0] degrades to a pointer: a different type from an array */
  94 # define BARF_UNLESS_AN_ARRAY(arr)                                              \
  95         BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
  96                                                            __typeof__(&(arr)[0])))
  97 #else
  98 # define BARF_UNLESS_AN_ARRAY(arr) 0
  99 #endif
 100 /*
 101  * ARRAY_SIZE - get the number of elements in a visible array
 102  * @x: the array whose size you want.
 103  *
 104  * This does not work on pointers, or arrays declared as [], or
 105  * function parameters.  With correct compiler support, such usage
 106  * will cause a build error (see the build_assert_or_zero macro).
 107  */
 108 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
 109
 110 #define bitsizeof(x)  (CHAR_BIT * sizeof(x))
 111
 112 #define maximum_signed_value_of_type(a) \
 113     (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
 114
 115 #define maximum_unsigned_value_of_type(a) \
 116     (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
 117
 118 /*
 119  * Signed integer overflow is undefined in C, so here's a helper macro
 120  * to detect if the sum of two integers will overflow.
 121  *
 122  * Requires: a >= 0, typeof(a) equals typeof(b)
 123  */
 124 #define signed_add_overflows(a, b) \
 125     ((b) > maximum_signed_value_of_type(a) - (a))
 126
 127 #define unsigned_add_overflows(a, b) \
 128     ((b) > maximum_unsigned_value_of_type(a) - (a))
 129
 130 /*
 131  * Returns true if the multiplication of "a" and "b" will
 132  * overflow. The types of "a" and "b" must match and must be unsigned.
 133  * Note that this macro evaluates "a" twice!
 134  */
 135 #define unsigned_mult_overflows(a, b) \
 136     ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
 137
 138 /*
 139  * Returns true if the left shift of "a" by "shift" bits will
 140  * overflow. The type of "a" must be unsigned.
 141  */
 142 #define unsigned_left_shift_overflows(a, shift) \
 143     ((shift) < bitsizeof(a) && \
 144      (a) > maximum_unsigned_value_of_type(a) >> (shift))
 145
 146 #ifdef __GNUC__
 147 #define TYPEOF(x) (__typeof__(x))
 148 #else
 149 #define TYPEOF(x)
 150 #endif
 151
 152 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 153 #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 154
 155 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 156
 157 /* Approximation of the length of the decimal representation of this type. */
 158 #define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 159
 160 #ifdef __MINGW64__
 161 #define _POSIX_C_SOURCE 1
 162 #elif defined(__sun__)
 163  /*
 164   * On Solaris, when _XOPEN_EXTENDED is set, its header file
 165   * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 166   * setting to say we are XPG5 or XPG6.  Also on Solaris,
 167   * XPG6 programs must be compiled with a c99 compiler, while
 168   * non XPG6 programs must be compiled with a pre-c99 compiler.
 169   */
 170 # if __STDC_VERSION__ - 0 >= 199901L
 171 # define _XOPEN_SOURCE 600
 172 # else
 173 # define _XOPEN_SOURCE 500
 174 # endif
 175 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 176       !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 177       !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
 178       !defined(__CYGWIN__)
 179 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 180 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 181 #endif
 182 #define _ALL_SOURCE 1
 183 #define _GNU_SOURCE 1
 184 #define _BSD_SOURCE 1
 185 #define _DEFAULT_SOURCE 1
 186 #define _NETBSD_SOURCE 1
 187 #define _SGI_SOURCE 1
 188
 189 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 190 # if !defined(_WIN32_WINNT)
 191 #  define _WIN32_WINNT 0x0600
 192 # endif
 193 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 194 #include <winsock2.h>
 195 #ifndef NO_UNIX_SOCKETS
 196 #include <afunix.h>
 197 #endif
 198 #include <windows.h>
 199 #define GIT_WINDOWS_NATIVE
 200 #endif
 201
 202 #include <unistd.h>
 203 #include <stdio.h>
 204 #include <sys/stat.h>
 205 #include <fcntl.h>
 206 #include <stddef.h>
 207 #include <stdlib.h>
 208 #include <stdarg.h>
 209 #include <string.h>
 210 #ifdef HAVE_STRINGS_H
 211 #include <strings.h> /* for strcasecmp() */
 212 #endif
 213 #include <errno.h>
 214 #include <limits.h>
 215 #ifdef NEEDS_SYS_PARAM_H
 216 #include <sys/param.h>
 217 #endif
 218 #include <sys/types.h>
 219 #include <dirent.h>
 220 #include <sys/time.h>
 221 #include <time.h>
 222 #include <signal.h>
 223 #include <assert.h>
 224 #include <regex.h>
 225 #include <utime.h>
 226 #include <syslog.h>
 227 #if !defined(NO_POLL_H)
 228 #include <poll.h>
 229 #elif !defined(NO_SYS_POLL_H)
 230 #include <sys/poll.h>
 231 #else
 232 /* Pull the compat stuff */
 233 #include <poll.h>
 234 #endif
 235 #ifdef HAVE_BSD_SYSCTL
 236 #include <sys/sysctl.h>
 237 #endif
 238
 239 #if defined(__CYGWIN__)
 240 #include "compat/win32/path-utils.h"
 241 #endif
 242 #if defined(__MINGW32__)
 243 /* pull in Windows compatibility stuff */
 244 #include "compat/win32/path-utils.h"
 245 #include "compat/mingw.h"
 246 #elif defined(_MSC_VER)
 247 #include "compat/win32/path-utils.h"
 248 #include "compat/msvc.h"
 249 #else
 250 #include <sys/utsname.h>
 251 #include <sys/wait.h>
 252 #include <sys/resource.h>
 253 #include <sys/socket.h>
 254 #include <sys/ioctl.h>
 255 #include <termios.h>
 256 #ifndef NO_SYS_SELECT_H
 257 #include <sys/select.h>
 258 #endif
 259 #include <netinet/in.h>
 260 #include <netinet/tcp.h>
 261 #include <arpa/inet.h>
 262 #include <netdb.h>
 263 #include <pwd.h>
 264 #include <sys/un.h>
 265 #ifndef NO_INTTYPES_H
 266 #include <inttypes.h>
 267 #else
 268 #include <stdint.h>
 269 #endif
 270 #ifdef NO_INTPTR_T
 271 /*
 272  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 273  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 274  * while on IP16 and IP16L32 it is "int" (resp. "short")
 275  * Size needs to match (or exceed) 'sizeof(void *)'.
 276  * We can't take "long long" here as not everybody has it.
 277  */
 278 typedef long intptr_t;
 279 typedef unsigned long uintptr_t;
 280 #endif
 281 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 282 #include <grp.h>
 283 #define _ALL_SOURCE 1
 284 #endif
 285
 286 /* used on Mac OS X */
 287 #ifdef PRECOMPOSE_UNICODE
 288 #include "compat/precompose_utf8.h"
 289 #else
 290 static inline const char *precompose_argv_prefix(int argc, const char **argv, const char *prefix)
 291 {
 292         return prefix;
 293 }
 294 static inline const char *precompose_string_if_needed(const char *in)
 295 {
 296         return in;
 297 }
 298
 299 #define probe_utf8_pathname_composition()
 300 #endif
 301
 302 #ifdef MKDIR_WO_TRAILING_SLASH
 303 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 304 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 305 #endif
 306
 307 #ifdef NO_STRUCT_ITIMERVAL
 308 struct itimerval {
 309         struct timeval it_interval;
 310         struct timeval it_value;
 311 };
 312 #endif
 313
 314 #ifdef NO_SETITIMER
 315 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
 316         return 0; /* pretend success */
 317 }
 318 #endif
 319
 320 #ifndef NO_LIBGEN_H
 321 #include <libgen.h>
 322 #else
 323 #define basename gitbasename
 324 char *gitbasename(char *);
 325 #define dirname gitdirname
 326 char *gitdirname(char *);
 327 #endif
 328
 329 #ifndef NO_ICONV
 330 #include <iconv.h>
 331 #endif
 332
 333 #ifndef NO_OPENSSL
 334 #ifdef __APPLE__
 335 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 336 #include <AvailabilityMacros.h>
 337 #undef DEPRECATED_ATTRIBUTE
 338 #define DEPRECATED_ATTRIBUTE
 339 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 340 #endif
 341 #include <openssl/ssl.h>
 342 #include <openssl/err.h>
 343 #endif
 344
 345 #ifdef HAVE_SYSINFO
 346 # include <sys/sysinfo.h>
 347 #endif
 348
 349 /* On most systems <netdb.h> would have given us this, but
 350  * not on some systems (e.g. z/OS).
 351  */
 352 #ifndef NI_MAXHOST
 353 #define NI_MAXHOST 1025
 354 #endif
 355
 356 #ifndef NI_MAXSERV
 357 #define NI_MAXSERV 32
 358 #endif
 359
 360 /* On most systems <limits.h> would have given us this, but
 361  * not on some systems (e.g. GNU/Hurd).
 362  */
 363 #ifndef PATH_MAX
 364 #define PATH_MAX 4096
 365 #endif
 366
 367 typedef uintmax_t timestamp_t;
 368 #define PRItime PRIuMAX
 369 #define parse_timestamp strtoumax
 370 #define TIME_MAX UINTMAX_MAX
 371 #define TIME_MIN 0
 372
 373 #ifndef PATH_SEP
 374 #define PATH_SEP ':'
 375 #endif
 376
 377 #ifdef HAVE_PATHS_H
 378 #include <paths.h>
 379 #endif
 380 #ifndef _PATH_DEFPATH
 381 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 382 #endif
 383
 384 #ifndef platform_core_config
 385 static inline int noop_core_config(const char *var, const char *value, void *cb)
 386 {
 387         return 0;
 388 }
 389 #define platform_core_config noop_core_config
 390 #endif
 391
 392 int lstat_cache_aware_rmdir(const char *path);
 393 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 394 #define rmdir lstat_cache_aware_rmdir
 395 #endif
 396
 397 #ifndef has_dos_drive_prefix
 398 static inline int git_has_dos_drive_prefix(const char *path)
 399 {
 400         return 0;
 401 }
 402 #define has_dos_drive_prefix git_has_dos_drive_prefix
 403 #endif
 404
 405 #ifndef skip_dos_drive_prefix
 406 static inline int git_skip_dos_drive_prefix(char **path)
 407 {
 408         return 0;
 409 }
 410 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 411 #endif
 412
 413 #ifndef is_dir_sep
 414 static inline int git_is_dir_sep(int c)
 415 {
 416         return c == '/';
 417 }
 418 #define is_dir_sep git_is_dir_sep
 419 #endif
 420
 421 #ifndef offset_1st_component
 422 static inline int git_offset_1st_component(const char *path)
 423 {
 424         return is_dir_sep(path[0]);
 425 }
 426 #define offset_1st_component git_offset_1st_component
 427 #endif
 428
 429 #ifndef is_valid_path
 430 #define is_valid_path(path) 1
 431 #endif
 432
 433 #ifndef find_last_dir_sep
 434 static inline char *git_find_last_dir_sep(const char *path)
 435 {
 436         return strrchr(path, '/');
 437 }
 438 #define find_last_dir_sep git_find_last_dir_sep
 439 #endif
 440
 441 #ifndef has_dir_sep
 442 static inline int git_has_dir_sep(const char *path)
 443 {
 444         return !!strchr(path, '/');
 445 }
 446 #define has_dir_sep(path) git_has_dir_sep(path)
 447 #endif
 448
 449 #ifndef query_user_email
 450 #define query_user_email() NULL
 451 #endif
 452
 453 #ifdef __TANDEM
 454 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 455 #include <floss.h(floss_getpwuid)>
 456 #ifndef NSIG
 457 /*
 458  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 459  * known, by detective work using kill -l as a list is all signals
 460  * instead of signal.h where it should be.
 461  */
 462 # define NSIG 100
 463 #endif
 464 #endif
 465
 466 #if defined(__HP_cc) && (__HP_cc >= 61000)
 467 #define NORETURN __attribute__((noreturn))
 468 #define NORETURN_PTR
 469 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 470 #define NORETURN __attribute__((__noreturn__))
 471 #define NORETURN_PTR __attribute__((__noreturn__))
 472 #elif defined(_MSC_VER)
 473 #define NORETURN __declspec(noreturn)
 474 #define NORETURN_PTR
 475 #else
 476 #define NORETURN
 477 #define NORETURN_PTR
 478 #ifndef __GNUC__
 479 #ifndef __attribute__
 480 #define __attribute__(x)
 481 #endif
 482 #endif
 483 #endif
 484
 485 /* The sentinel attribute is valid from gcc version 4.0 */
 486 #if defined(__GNUC__) && (__GNUC__ >= 4)
 487 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 488 #else
 489 #define LAST_ARG_MUST_BE_NULL
 490 #endif
 491
 492 #define MAYBE_UNUSED __attribute__((__unused__))
 493
 494 #include "compat/bswap.h"
 495
 496 #include "wildmatch.h"
 497
 498 struct strbuf;
 499
 500 /* General helper functions */
 501 NORETURN void usage(const char *err);
 502 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 503 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 504 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 505 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
 506 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 507 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 508 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 509 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 510 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 511
 512 #ifndef NO_OPENSSL
 513 #ifdef APPLE_COMMON_CRYPTO
 514 #include "compat/apple-common-crypto.h"
 515 #else
 516 #include <openssl/evp.h>
 517 #include <openssl/hmac.h>
 518 #endif /* APPLE_COMMON_CRYPTO */
 519 #include <openssl/x509v3.h>
 520 #endif /* NO_OPENSSL */
 521
 522 /*
 523  * Let callers be aware of the constant return value; this can help
 524  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 525  * because some compilers may not support variadic macros. Since we're only
 526  * trying to help gcc, anyway, it's OK; other compilers will fall back to
 527  * using the function as usual.
 528  */
 529 #if defined(__GNUC__)
 530 static inline int const_error(void)
 531 {
 532         return -1;
 533 }
 534 #define error(...) (error(__VA_ARGS__), const_error())
 535 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 536 #endif
 537
 538 typedef void (*report_fn)(const char *, va_list params);
 539
 540 void set_die_routine(NORETURN_PTR report_fn routine);
 541 report_fn get_die_message_routine(void);
 542 void set_error_routine(report_fn routine);
 543 report_fn get_error_routine(void);
 544 void set_warn_routine(report_fn routine);
 545 report_fn get_warn_routine(void);
 546 void set_die_is_recursing_routine(int (*routine)(void));
 547
 548 int starts_with(const char *str, const char *prefix);
 549 int istarts_with(const char *str, const char *prefix);
 550
 551 /*
 552  * If the string "str" begins with the string found in "prefix", return 1.
 553  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 554  * the string right after the prefix).
 555  *
 556  * Otherwise, return 0 and leave "out" untouched.
 557  *
 558  * Examples:
 559  *
 560  *   [extract branch name, fail if not a branch]
 561  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 562  *      return -1;
 563  *
 564  *   [skip prefix if present, otherwise use whole string]
 565  *   skip_prefix(name, "refs/heads/", &name);
 566  */
 567 static inline int skip_prefix(const char *str, const char *prefix,
 568                               const char **out)
 569 {
 570         do {
 571                 if (!*prefix) {
 572                         *out = str;
 573                         return 1;
 574                 }
 575         } while (*str++ == *prefix++);
 576         return 0;
 577 }
 578
 579 /*
 580  * If the string "str" is the same as the string in "prefix", then the "arg"
 581  * parameter is set to the "def" parameter and 1 is returned.
 582  * If the string "str" begins with the string found in "prefix" and then a
 583  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 584  * (i.e., to the point in the string right after the prefix and the "=" sign),
 585  * and 1 is returned.
 586  *
 587  * Otherwise, return 0 and leave "arg" untouched.
 588  *
 589  * When we accept both a "--key" and a "--key=<val>" option, this function
 590  * can be used instead of !strcmp(arg, "--key") and then
 591  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 592  */
 593 int skip_to_optional_arg_default(const char *str, const char *prefix,
 594                                  const char **arg, const char *def);
 595
 596 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 597                                        const char **arg)
 598 {
 599         return skip_to_optional_arg_default(str, prefix, arg, "");
 600 }
 601
 602 /*
 603  * Like skip_prefix, but promises never to read past "len" bytes of the input
 604  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 605  */
 606 static inline int skip_prefix_mem(const char *buf, size_t len,
 607                                   const char *prefix,
 608                                   const char **out, size_t *outlen)
 609 {
 610         size_t prefix_len = strlen(prefix);
 611         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 612                 *out = buf + prefix_len;
 613                 *outlen = len - prefix_len;
 614                 return 1;
 615         }
 616         return 0;
 617 }
 618
 619 /*
 620  * If buf ends with suffix, return 1 and subtract the length of the suffix
 621  * from *len. Otherwise, return 0 and leave *len untouched.
 622  */
 623 static inline int strip_suffix_mem(const char *buf, size_t *len,
 624                                    const char *suffix)
 625 {
 626         size_t suflen = strlen(suffix);
 627         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 628                 return 0;
 629         *len -= suflen;
 630         return 1;
 631 }
 632
 633 /*
 634  * If str ends with suffix, return 1 and set *len to the size of the string
 635  * without the suffix. Otherwise, return 0 and set *len to the size of the
 636  * string.
 637  *
 638  * Note that we do _not_ NUL-terminate str to the new length.
 639  */
 640 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 641 {
 642         *len = strlen(str);
 643         return strip_suffix_mem(str, len, suffix);
 644 }
 645
 646 static inline int ends_with(const char *str, const char *suffix)
 647 {
 648         size_t len;
 649         return strip_suffix(str, suffix, &len);
 650 }
 651
 652 #define SWAP(a, b) do {                                         \
 653         void *_swap_a_ptr = &(a);                               \
 654         void *_swap_b_ptr = &(b);                               \
 655         unsigned char _swap_buffer[sizeof(a)];                  \
 656         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 657         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 658                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 659         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 660 } while (0)
 661
 662 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 663
 664 #ifndef PROT_READ
 665 #define PROT_READ 1
 666 #define PROT_WRITE 2
 667 #define MAP_PRIVATE 1
 668 #endif
 669
 670 #define mmap git_mmap
 671 #define munmap git_munmap
 672 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 673 int git_munmap(void *start, size_t length);
 674
 675 #else /* NO_MMAP || USE_WIN32_MMAP */
 676
 677 #include <sys/mman.h>
 678
 679 #endif /* NO_MMAP || USE_WIN32_MMAP */
 680
 681 #ifdef NO_MMAP
 682
 683 /* This value must be multiple of (pagesize * 2) */
 684 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 685
 686 #else /* NO_MMAP */
 687
 688 /* This value must be multiple of (pagesize * 2) */
 689 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 690         (sizeof(void*) >= 8 \
 691                 ?  1 * 1024 * 1024 * 1024 \
 692                 : 32 * 1024 * 1024)
 693
 694 #endif /* NO_MMAP */
 695
 696 #ifndef MAP_FAILED
 697 #define MAP_FAILED ((void *)-1)
 698 #endif
 699
 700 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 701 #define on_disk_bytes(st) ((st).st_size)
 702 #else
 703 #define on_disk_bytes(st) ((st).st_blocks * 512)
 704 #endif
 705
 706 #ifdef NEEDS_MODE_TRANSLATION
 707 #undef S_IFMT
 708 #undef S_IFREG
 709 #undef S_IFDIR
 710 #undef S_IFLNK
 711 #undef S_IFBLK
 712 #undef S_IFCHR
 713 #undef S_IFIFO
 714 #undef S_IFSOCK
 715 #define S_IFMT   0170000
 716 #define S_IFREG  0100000
 717 #define S_IFDIR  0040000
 718 #define S_IFLNK  0120000
 719 #define S_IFBLK  0060000
 720 #define S_IFCHR  0020000
 721 #define S_IFIFO  0010000
 722 #define S_IFSOCK 0140000
 723 #ifdef stat
 724 #undef stat
 725 #endif
 726 #define stat(path, buf) git_stat(path, buf)
 727 int git_stat(const char *, struct stat *);
 728 #ifdef fstat
 729 #undef fstat
 730 #endif
 731 #define fstat(fd, buf) git_fstat(fd, buf)
 732 int git_fstat(int, struct stat *);
 733 #ifdef lstat
 734 #undef lstat
 735 #endif
 736 #define lstat(path, buf) git_lstat(path, buf)
 737 int git_lstat(const char *, struct stat *);
 738 #endif
 739
 740 #define DEFAULT_PACKED_GIT_LIMIT \
 741         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 742
 743 #ifdef NO_PREAD
 744 #define pread git_pread
 745 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 746 #endif
 747 /*
 748  * Forward decl that will remind us if its twin in cache.h changes.
 749  * This function is used in compat/pread.c.  But we can't include
 750  * cache.h there.
 751  */
 752 ssize_t read_in_full(int fd, void *buf, size_t count);
 753
 754 #ifdef NO_SETENV
 755 #define setenv gitsetenv
 756 int gitsetenv(const char *, const char *, int);
 757 #endif
 758
 759 #ifdef NO_MKDTEMP
 760 #define mkdtemp gitmkdtemp
 761 char *gitmkdtemp(char *);
 762 #endif
 763
 764 #ifdef NO_UNSETENV
 765 #define unsetenv gitunsetenv
 766 int gitunsetenv(const char *);
 767 #endif
 768
 769 #ifdef NO_STRCASESTR
 770 #define strcasestr gitstrcasestr
 771 char *gitstrcasestr(const char *haystack, const char *needle);
 772 #endif
 773
 774 #ifdef NO_STRLCPY
 775 #define strlcpy gitstrlcpy
 776 size_t gitstrlcpy(char *, const char *, size_t);
 777 #endif
 778
 779 #ifdef NO_STRTOUMAX
 780 #define strtoumax gitstrtoumax
 781 uintmax_t gitstrtoumax(const char *, char **, int);
 782 #define strtoimax gitstrtoimax
 783 intmax_t gitstrtoimax(const char *, char **, int);
 784 #endif
 785
 786 #ifdef NO_HSTRERROR
 787 #define hstrerror githstrerror
 788 const char *githstrerror(int herror);
 789 #endif
 790
 791 #ifdef NO_MEMMEM
 792 #define memmem gitmemmem
 793 void *gitmemmem(const void *haystack, size_t haystacklen,
 794                 const void *needle, size_t needlelen);
 795 #endif
 796
 797 #ifdef OVERRIDE_STRDUP
 798 #ifdef strdup
 799 #undef strdup
 800 #endif
 801 #define strdup gitstrdup
 802 char *gitstrdup(const char *s);
 803 #endif
 804
 805 #ifdef NO_GETPAGESIZE
 806 #define getpagesize() sysconf(_SC_PAGESIZE)
 807 #endif
 808
 809 #ifndef O_CLOEXEC
 810 #define O_CLOEXEC 0
 811 #endif
 812
 813 #ifdef FREAD_READS_DIRECTORIES
 814 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 815 #  ifdef fopen
 816 #   undef fopen
 817 #  endif
 818 #  define fopen(a,b) git_fopen(a,b)
 819 # endif
 820 FILE *git_fopen(const char*, const char*);
 821 #endif
 822
 823 #ifdef SNPRINTF_RETURNS_BOGUS
 824 #ifdef snprintf
 825 #undef snprintf
 826 #endif
 827 #define snprintf git_snprintf
 828 int git_snprintf(char *str, size_t maxsize,
 829                  const char *format, ...);
 830 #ifdef vsnprintf
 831 #undef vsnprintf
 832 #endif
 833 #define vsnprintf git_vsnprintf
 834 int git_vsnprintf(char *str, size_t maxsize,
 835                   const char *format, va_list ap);
 836 #endif
 837
 838 #ifdef OPEN_RETURNS_EINTR
 839 #undef open
 840 #define open git_open_with_retry
 841 int git_open_with_retry(const char *path, int flag, ...);
 842 #endif
 843
 844 #ifdef __GLIBC_PREREQ
 845 #if __GLIBC_PREREQ(2, 1)
 846 #define HAVE_STRCHRNUL
 847 #endif
 848 #endif
 849
 850 #ifndef HAVE_STRCHRNUL
 851 #define strchrnul gitstrchrnul
 852 static inline char *gitstrchrnul(const char *s, int c)
 853 {
 854         while (*s && *s != c)
 855                 s++;
 856         return (char *)s;
 857 }
 858 #endif
 859
 860 #ifdef NO_INET_PTON
 861 int inet_pton(int af, const char *src, void *dst);
 862 #endif
 863
 864 #ifdef NO_INET_NTOP
 865 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 866 #endif
 867
 868 #ifdef NO_PTHREADS
 869 #define atexit git_atexit
 870 int git_atexit(void (*handler)(void));
 871 #endif
 872
 873 static inline size_t st_add(size_t a, size_t b)
 874 {
 875         if (unsigned_add_overflows(a, b))
 876                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 877                     (uintmax_t)a, (uintmax_t)b);
 878         return a + b;
 879 }
 880 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 881 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 882
 883 static inline size_t st_mult(size_t a, size_t b)
 884 {
 885         if (unsigned_mult_overflows(a, b))
 886                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 887                     (uintmax_t)a, (uintmax_t)b);
 888         return a * b;
 889 }
 890
 891 static inline size_t st_sub(size_t a, size_t b)
 892 {
 893         if (a < b)
 894                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 895                     (uintmax_t)a, (uintmax_t)b);
 896         return a - b;
 897 }
 898
 899 static inline size_t st_left_shift(size_t a, unsigned shift)
 900 {
 901         if (unsigned_left_shift_overflows(a, shift))
 902                 die("size_t overflow: %"PRIuMAX" << %u",
 903                     (uintmax_t)a, shift);
 904         return a << shift;
 905 }
 906
 907 static inline unsigned long cast_size_t_to_ulong(size_t a)
 908 {
 909         if (a != (unsigned long)a)
 910                 die("object too large to read on this platform: %"
 911                     PRIuMAX" is cut off to %lu",
 912                     (uintmax_t)a, (unsigned long)a);
 913         return (unsigned long)a;
 914 }
 915
 916 #ifdef HAVE_ALLOCA_H
 917 # include <alloca.h>
 918 # define xalloca(size)      (alloca(size))
 919 # define xalloca_free(p)    do {} while (0)
 920 #else
 921 # define xalloca(size)      (xmalloc(size))
 922 # define xalloca_free(p)    (free(p))
 923 #endif
 924 char *xstrdup(const char *str);
 925 void *xmalloc(size_t size);
 926 void *xmallocz(size_t size);
 927 void *xmallocz_gently(size_t size);
 928 void *xmemdupz(const void *data, size_t len);
 929 char *xstrndup(const char *str, size_t len);
 930 void *xrealloc(void *ptr, size_t size);
 931 void *xcalloc(size_t nmemb, size_t size);
 932 void xsetenv(const char *name, const char *value, int overwrite);
 933 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 934 const char *mmap_os_err(void);
 935 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 936 int xopen(const char *path, int flags, ...);
 937 ssize_t xread(int fd, void *buf, size_t len);
 938 ssize_t xwrite(int fd, const void *buf, size_t len);
 939 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 940 int xdup(int fd);
 941 FILE *xfopen(const char *path, const char *mode);
 942 FILE *xfdopen(int fd, const char *mode);
 943 int xmkstemp(char *temp_filename);
 944 int xmkstemp_mode(char *temp_filename, int mode);
 945 char *xgetcwd(void);
 946 FILE *fopen_for_writing(const char *path);
 947 FILE *fopen_or_warn(const char *path, const char *mode);
 948
 949 /*
 950  * Like strncmp, but only return zero if s is NUL-terminated and exactly len
 951  * characters long.  If it is not, consider it greater than t.
 952  */
 953 int xstrncmpz(const char *s, const char *t, size_t len);
 954
 955 /*
 956  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 957  * that ptr is used twice, so don't pass e.g. ptr++.
 958  */
 959 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 960
 961 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 962 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
 963 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 964
 965 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 966         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 967 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 968 {
 969         if (n)
 970                 memcpy(dst, src, st_mult(size, n));
 971 }
 972
 973 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
 974         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 975 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
 976 {
 977         if (n)
 978                 memmove(dst, src, st_mult(size, n));
 979 }
 980
 981 /*
 982  * These functions help you allocate structs with flex arrays, and copy
 983  * the data directly into the array. For example, if you had:
 984  *
 985  *   struct foo {
 986  *     int bar;
 987  *     char name[FLEX_ARRAY];
 988  *   };
 989  *
 990  * you can do:
 991  *
 992  *   struct foo *f;
 993  *   FLEX_ALLOC_MEM(f, name, src, len);
 994  *
 995  * to allocate a "foo" with the contents of "src" in the "name" field.
 996  * The resulting struct is automatically zero'd, and the flex-array field
 997  * is NUL-terminated (whether the incoming src buffer was or not).
 998  *
 999  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1000  * but do want to store a pointer to some extra data in the same allocated
1001  * block. For example, if you have:
1002  *
1003  *   struct foo {
1004  *     char *name;
1005  *     int bar;
1006  *   };
1007  *
1008  * you can do:
1009  *
1010  *   struct foo *f;
1011  *   FLEXPTR_ALLOC_STR(f, name, src);
1012  *
1013  * and "name" will point to a block of memory after the struct, which will be
1014  * freed along with the struct (but the pointer can be repointed anywhere).
1015  *
1016  * The *_STR variants accept a string parameter rather than a ptr/len
1017  * combination.
1018  *
1019  * Note that these macros will evaluate the first parameter multiple
1020  * times, and it must be assignable as an lvalue.
1021  */
1022 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1023         size_t flex_array_len_ = (len); \
1024         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1025         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1026 } while (0)
1027 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1028         size_t flex_array_len_ = (len); \
1029         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1030         memcpy((x) + 1, (buf), flex_array_len_); \
1031         (x)->ptrname = (void *)((x)+1); \
1032 } while(0)
1033 #define FLEX_ALLOC_STR(x, flexname, str) \
1034         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1035 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1036         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1037
1038 static inline char *xstrdup_or_null(const char *str)
1039 {
1040         return str ? xstrdup(str) : NULL;
1041 }
1042
1043 static inline size_t xsize_t(off_t len)
1044 {
1045         if (len < 0 || (uintmax_t) len > SIZE_MAX)
1046                 die("Cannot handle files this big");
1047         return (size_t) len;
1048 }
1049
1050 __attribute__((format (printf, 3, 4)))
1051 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1052
1053 #ifndef HOST_NAME_MAX
1054 #define HOST_NAME_MAX 256
1055 #endif
1056
1057 int xgethostname(char *buf, size_t len);
1058
1059 /* in ctype.c, for kwset users */
1060 extern const unsigned char tolower_trans_tbl[256];
1061
1062 /* Sane ctype - no locale, and works with signed chars */
1063 #undef isascii
1064 #undef isspace
1065 #undef isdigit
1066 #undef isalpha
1067 #undef isalnum
1068 #undef isprint
1069 #undef islower
1070 #undef isupper
1071 #undef tolower
1072 #undef toupper
1073 #undef iscntrl
1074 #undef ispunct
1075 #undef isxdigit
1076
1077 extern const unsigned char sane_ctype[256];
1078 #define GIT_SPACE 0x01
1079 #define GIT_DIGIT 0x02
1080 #define GIT_ALPHA 0x04
1081 #define GIT_GLOB_SPECIAL 0x08
1082 #define GIT_REGEX_SPECIAL 0x10
1083 #define GIT_PATHSPEC_MAGIC 0x20
1084 #define GIT_CNTRL 0x40
1085 #define GIT_PUNCT 0x80
1086 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1087 #define isascii(x) (((x) & ~0x7f) == 0)
1088 #define isspace(x) sane_istest(x,GIT_SPACE)
1089 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1090 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1091 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1092 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1093 #define islower(x) sane_iscase(x, 1)
1094 #define isupper(x) sane_iscase(x, 0)
1095 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1096 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1097 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1098 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1099                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1100 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1101 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1102 #define toupper(x) sane_case((unsigned char)(x), 0)
1103 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1104
1105 static inline int sane_case(int x, int high)
1106 {
1107         if (sane_istest(x, GIT_ALPHA))
1108                 x = (x & ~0x20) | high;
1109         return x;
1110 }
1111
1112 static inline int sane_iscase(int x, int is_lower)
1113 {
1114         if (!sane_istest(x, GIT_ALPHA))
1115                 return 0;
1116
1117         if (is_lower)
1118                 return (x & 0x20) != 0;
1119         else
1120                 return (x & 0x20) == 0;
1121 }
1122
1123 /*
1124  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1125  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1126  * locale-specific conversions).
1127  */
1128 static inline int skip_iprefix(const char *str, const char *prefix,
1129                                const char **out)
1130 {
1131         do {
1132                 if (!*prefix) {
1133                         *out = str;
1134                         return 1;
1135                 }
1136         } while (tolower(*str++) == tolower(*prefix++));
1137         return 0;
1138 }
1139
1140 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1141 {
1142         unsigned long ul;
1143         char *p;
1144
1145         errno = 0;
1146         /* negative values would be accepted by strtoul */
1147         if (strchr(s, '-'))
1148                 return -1;
1149         ul = strtoul(s, &p, base);
1150         if (errno || *p || p == s || (unsigned int) ul != ul)
1151                 return -1;
1152         *result = ul;
1153         return 0;
1154 }
1155
1156 static inline int strtol_i(char const *s, int base, int *result)
1157 {
1158         long ul;
1159         char *p;
1160
1161         errno = 0;
1162         ul = strtol(s, &p, base);
1163         if (errno || *p || p == s || (int) ul != ul)
1164                 return -1;
1165         *result = ul;
1166         return 0;
1167 }
1168
1169 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1170                       int(*compar)(const void *, const void *));
1171 #ifdef INTERNAL_QSORT
1172 #define qsort git_stable_qsort
1173 #endif
1174
1175 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1176 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1177                               int(*compar)(const void *, const void *))
1178 {
1179         if (nmemb > 1)
1180                 qsort(base, nmemb, size, compar);
1181 }
1182
1183 #define STABLE_QSORT(base, n, compar) \
1184         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1185
1186 #ifndef HAVE_ISO_QSORT_S
1187 int git_qsort_s(void *base, size_t nmemb, size_t size,
1188                 int (*compar)(const void *, const void *, void *), void *ctx);
1189 #define qsort_s git_qsort_s
1190 #endif
1191
1192 #define QSORT_S(base, n, compar, ctx) do {                      \
1193         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1194                 BUG("qsort_s() failed");                        \
1195 } while (0)
1196
1197 #ifndef REG_STARTEND
1198 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1199 #endif
1200
1201 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1202                               size_t nmatch, regmatch_t pmatch[], int eflags)
1203 {
1204         assert(nmatch > 0 && pmatch);
1205         pmatch[0].rm_so = 0;
1206         pmatch[0].rm_eo = size;
1207         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1208 }
1209
1210 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1211 # define FORCE_DIR_SET_GID S_ISGID
1212 #else
1213 # define FORCE_DIR_SET_GID 0
1214 #endif
1215
1216 #ifdef NO_NSEC
1217 #undef USE_NSEC
1218 #define ST_CTIME_NSEC(st) 0
1219 #define ST_MTIME_NSEC(st) 0
1220 #else
1221 #ifdef USE_ST_TIMESPEC
1222 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1223 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1224 #else
1225 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1226 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1227 #endif
1228 #endif
1229
1230 #ifdef UNRELIABLE_FSTAT
1231 #define fstat_is_reliable() 0
1232 #else
1233 #define fstat_is_reliable() 1
1234 #endif
1235
1236 #ifndef va_copy
1237 /*
1238  * Since an obvious implementation of va_list would be to make it a
1239  * pointer into the stack frame, a simple assignment will work on
1240  * many systems.  But let's try to be more portable.
1241  */
1242 #ifdef __va_copy
1243 #define va_copy(dst, src) __va_copy(dst, src)
1244 #else
1245 #define va_copy(dst, src) ((dst) = (src))
1246 #endif
1247 #endif
1248
1249 /*
1250  * This is always defined as a first step towards making the use of variadic
1251  * macros unconditional. If it causes compilation problems on your platform,
1252  * please report it to the Git mailing list at git@vger.kernel.org.
1253  */
1254 #define HAVE_VARIADIC_MACROS 1
1255
1256 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1257 extern int BUG_exit_code;
1258
1259 #ifdef HAVE_VARIADIC_MACROS
1260 __attribute__((format (printf, 3, 4))) NORETURN
1261 void BUG_fl(const char *file, int line, const char *fmt, ...);
1262 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1263 #else
1264 __attribute__((format (printf, 1, 2))) NORETURN
1265 void BUG(const char *fmt, ...);
1266 #endif
1267
1268 /*
1269  * Preserves errno, prints a message, but gives no warning for ENOENT.
1270  * Returns 0 on success, which includes trying to unlink an object that does
1271  * not exist.
1272  */
1273 int unlink_or_warn(const char *path);
1274  /*
1275   * Tries to unlink file.  Returns 0 if unlink succeeded
1276   * or the file already didn't exist.  Returns -1 and
1277   * appends a message to err suitable for
1278   * 'error("%s", err->buf)' on error.
1279   */
1280 int unlink_or_msg(const char *file, struct strbuf *err);
1281 /*
1282  * Preserves errno, prints a message, but gives no warning for ENOENT.
1283  * Returns 0 on success, which includes trying to remove a directory that does
1284  * not exist.
1285  */
1286 int rmdir_or_warn(const char *path);
1287 /*
1288  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1289  * the supplied file mode.
1290  */
1291 int remove_or_warn(unsigned int mode, const char *path);
1292
1293 /*
1294  * Call access(2), but warn for any error except "missing file"
1295  * (ENOENT or ENOTDIR).
1296  */
1297 #define ACCESS_EACCES_OK (1U << 0)
1298 int access_or_warn(const char *path, int mode, unsigned flag);
1299 int access_or_die(const char *path, int mode, unsigned flag);
1300
1301 /* Warn on an inaccessible file if errno indicates this is an error */
1302 int warn_on_fopen_errors(const char *path);
1303
1304 /*
1305  * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1306  * may be racy. Do not use this as protection against an attacker who can
1307  * simultaneously create paths.
1308  */
1309 int open_nofollow(const char *path, int flags);
1310
1311 #ifndef SHELL_PATH
1312 # define SHELL_PATH "/bin/sh"
1313 #endif
1314
1315 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1316 static inline void flockfile(FILE *fh)
1317 {
1318         ; /* nothing */
1319 }
1320 static inline void funlockfile(FILE *fh)
1321 {
1322         ; /* nothing */
1323 }
1324 #define getc_unlocked(fh) getc(fh)
1325 #endif
1326
1327 #ifdef FILENO_IS_A_MACRO
1328 int git_fileno(FILE *stream);
1329 # ifndef COMPAT_CODE_FILENO
1330 #  undef fileno
1331 #  define fileno(p) git_fileno(p)
1332 # endif
1333 #endif
1334
1335 #ifdef NEED_ACCESS_ROOT_HANDLER
1336 int git_access(const char *path, int mode);
1337 # ifndef COMPAT_CODE_ACCESS
1338 #  ifdef access
1339 #  undef access
1340 #  endif
1341 #  define access(path, mode) git_access(path, mode)
1342 # endif
1343 #endif
1344
1345 /*
1346  * Our code often opens a path to an optional file, to work on its
1347  * contents when we can successfully open it.  We can ignore a failure
1348  * to open if such an optional file does not exist, but we do want to
1349  * report a failure in opening for other reasons (e.g. we got an I/O
1350  * error, or the file is there, but we lack the permission to open).
1351  *
1352  * Call this function after seeing an error from open() or fopen() to
1353  * see if the errno indicates a missing file that we can safely ignore.
1354  */
1355 static inline int is_missing_file_error(int errno_)
1356 {
1357         return (errno_ == ENOENT || errno_ == ENOTDIR);
1358 }
1359
1360 int cmd_main(int, const char **);
1361
1362 /*
1363  * Intercept all calls to exit() and route them to trace2 to
1364  * optionally emit a message before calling the real exit().
1365  */
1366 int trace2_cmd_exit_fl(const char *file, int line, int code);
1367 #define exit(code) exit(trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
1368
1369 /*
1370  * You can mark a stack variable with UNLEAK(var) to avoid it being
1371  * reported as a leak by tools like LSAN or valgrind. The argument
1372  * should generally be the variable itself (not its address and not what
1373  * it points to). It's safe to use this on pointers which may already
1374  * have been freed, or on pointers which may still be in use.
1375  *
1376  * Use this _only_ for a variable that leaks by going out of scope at
1377  * program exit (so only from cmd_* functions or their direct helpers).
1378  * Normal functions, especially those which may be called multiple
1379  * times, should actually free their memory. This is only meant as
1380  * an annotation, and does nothing in non-leak-checking builds.
1381  */
1382 #ifdef SUPPRESS_ANNOTATED_LEAKS
1383 void unleak_memory(const void *ptr, size_t len);
1384 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1385 #else
1386 #define UNLEAK(var) do {} while (0)
1387 #endif
1388
1389 /*
1390  * This include must come after system headers, since it introduces macros that
1391  * replace system names.
1392  */
1393 #include "banned.h"
1394
1395 /*
1396  * container_of - Get the address of an object containing a field.
1397  *
1398  * @ptr: pointer to the field.
1399  * @type: type of the object.
1400  * @member: name of the field within the object.
1401  */
1402 #define container_of(ptr, type, member) \
1403         ((type *) ((char *)(ptr) - offsetof(type, member)))
1404
1405 /*
1406  * helper function for `container_of_or_null' to avoid multiple
1407  * evaluation of @ptr
1408  */
1409 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1410 {
1411         return ptr ? (char *)ptr - offset : NULL;
1412 }
1413
1414 /*
1415  * like `container_of', but allows returned value to be NULL
1416  */
1417 #define container_of_or_null(ptr, type, member) \
1418         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1419
1420 /*
1421  * like offsetof(), but takes a pointer to a variable of type which
1422  * contains @member, instead of a specified type.
1423  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1424  * everywhere.
1425  */
1426 #if defined(__GNUC__) /* clang sets this, too */
1427 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1428 #else /* !__GNUC__ */
1429 #define OFFSETOF_VAR(ptr, member) \
1430         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1431 #endif /* !__GNUC__ */
1432
1433 void sleep_millisec(int millisec);
1434
1435 #endif