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 #ifdef HAVE_RTLGENRANDOM
 201 /* This is required to get access to RtlGenRandom. */
 202 #define SystemFunction036 NTAPI SystemFunction036
 203 #include <NTSecAPI.h>
 204 #undef SystemFunction036
 205 #endif
 206 #endif
 207
 208 #include <unistd.h>
 209 #include <stdio.h>
 210 #include <sys/stat.h>
 211 #include <fcntl.h>
 212 #include <stddef.h>
 213 #include <stdlib.h>
 214 #include <stdarg.h>
 215 #include <string.h>
 216 #ifdef HAVE_STRINGS_H
 217 #include <strings.h> /* for strcasecmp() */
 218 #endif
 219 #include <errno.h>
 220 #include <limits.h>
 221 #ifdef NEEDS_SYS_PARAM_H
 222 #include <sys/param.h>
 223 #endif
 224 #include <sys/types.h>
 225 #include <dirent.h>
 226 #include <sys/time.h>
 227 #include <time.h>
 228 #include <signal.h>
 229 #include <assert.h>
 230 #include <regex.h>
 231 #include <utime.h>
 232 #include <syslog.h>
 233 #if !defined(NO_POLL_H)
 234 #include <poll.h>
 235 #elif !defined(NO_SYS_POLL_H)
 236 #include <sys/poll.h>
 237 #else
 238 /* Pull the compat stuff */
 239 #include <poll.h>
 240 #endif
 241 #ifdef HAVE_BSD_SYSCTL
 242 #include <sys/sysctl.h>
 243 #endif
 244
 245 #if defined(__CYGWIN__)
 246 #include "compat/win32/path-utils.h"
 247 #endif
 248 #if defined(__MINGW32__)
 249 /* pull in Windows compatibility stuff */
 250 #include "compat/win32/path-utils.h"
 251 #include "compat/mingw.h"
 252 #elif defined(_MSC_VER)
 253 #include "compat/win32/path-utils.h"
 254 #include "compat/msvc.h"
 255 #else
 256 #include <sys/utsname.h>
 257 #include <sys/wait.h>
 258 #include <sys/resource.h>
 259 #include <sys/socket.h>
 260 #include <sys/ioctl.h>
 261 #include <termios.h>
 262 #ifndef NO_SYS_SELECT_H
 263 #include <sys/select.h>
 264 #endif
 265 #include <netinet/in.h>
 266 #include <netinet/tcp.h>
 267 #include <arpa/inet.h>
 268 #include <netdb.h>
 269 #include <pwd.h>
 270 #include <sys/un.h>
 271 #ifndef NO_INTTYPES_H
 272 #include <inttypes.h>
 273 #else
 274 #include <stdint.h>
 275 #endif
 276 #ifdef HAVE_ARC4RANDOM_LIBBSD
 277 #include <bsd/stdlib.h>
 278 #endif
 279 #ifdef HAVE_GETRANDOM
 280 #include <sys/random.h>
 281 #endif
 282 #ifdef NO_INTPTR_T
 283 /*
 284  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 285  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 286  * while on IP16 and IP16L32 it is "int" (resp. "short")
 287  * Size needs to match (or exceed) 'sizeof(void *)'.
 288  * We can't take "long long" here as not everybody has it.
 289  */
 290 typedef long intptr_t;
 291 typedef unsigned long uintptr_t;
 292 #endif
 293 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 294 #include <grp.h>
 295 #define _ALL_SOURCE 1
 296 #endif
 297
 298 /* used on Mac OS X */
 299 #ifdef PRECOMPOSE_UNICODE
 300 #include "compat/precompose_utf8.h"
 301 #else
 302 static inline const char *precompose_argv_prefix(int argc, const char **argv, const char *prefix)
 303 {
 304         return prefix;
 305 }
 306 static inline const char *precompose_string_if_needed(const char *in)
 307 {
 308         return in;
 309 }
 310
 311 #define probe_utf8_pathname_composition()
 312 #endif
 313
 314 #ifdef MKDIR_WO_TRAILING_SLASH
 315 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 316 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 317 #endif
 318
 319 #ifdef NO_STRUCT_ITIMERVAL
 320 struct itimerval {
 321         struct timeval it_interval;
 322         struct timeval it_value;
 323 };
 324 #endif
 325
 326 #ifdef NO_SETITIMER
 327 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
 328         return 0; /* pretend success */
 329 }
 330 #endif
 331
 332 #ifndef NO_LIBGEN_H
 333 #include <libgen.h>
 334 #else
 335 #define basename gitbasename
 336 char *gitbasename(char *);
 337 #define dirname gitdirname
 338 char *gitdirname(char *);
 339 #endif
 340
 341 #ifndef NO_ICONV
 342 #include <iconv.h>
 343 #endif
 344
 345 #ifndef NO_OPENSSL
 346 #ifdef __APPLE__
 347 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 348 #include <AvailabilityMacros.h>
 349 #undef DEPRECATED_ATTRIBUTE
 350 #define DEPRECATED_ATTRIBUTE
 351 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 352 #endif
 353 #include <openssl/ssl.h>
 354 #include <openssl/err.h>
 355 #endif
 356
 357 #ifdef HAVE_SYSINFO
 358 # include <sys/sysinfo.h>
 359 #endif
 360
 361 /* On most systems <netdb.h> would have given us this, but
 362  * not on some systems (e.g. z/OS).
 363  */
 364 #ifndef NI_MAXHOST
 365 #define NI_MAXHOST 1025
 366 #endif
 367
 368 #ifndef NI_MAXSERV
 369 #define NI_MAXSERV 32
 370 #endif
 371
 372 /* On most systems <limits.h> would have given us this, but
 373  * not on some systems (e.g. GNU/Hurd).
 374  */
 375 #ifndef PATH_MAX
 376 #define PATH_MAX 4096
 377 #endif
 378
 379 typedef uintmax_t timestamp_t;
 380 #define PRItime PRIuMAX
 381 #define parse_timestamp strtoumax
 382 #define TIME_MAX UINTMAX_MAX
 383 #define TIME_MIN 0
 384
 385 #ifndef PATH_SEP
 386 #define PATH_SEP ':'
 387 #endif
 388
 389 #ifdef HAVE_PATHS_H
 390 #include <paths.h>
 391 #endif
 392 #ifndef _PATH_DEFPATH
 393 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 394 #endif
 395
 396 #ifndef platform_core_config
 397 static inline int noop_core_config(const char *var, const char *value, void *cb)
 398 {
 399         return 0;
 400 }
 401 #define platform_core_config noop_core_config
 402 #endif
 403
 404 int lstat_cache_aware_rmdir(const char *path);
 405 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 406 #define rmdir lstat_cache_aware_rmdir
 407 #endif
 408
 409 #ifndef has_dos_drive_prefix
 410 static inline int git_has_dos_drive_prefix(const char *path)
 411 {
 412         return 0;
 413 }
 414 #define has_dos_drive_prefix git_has_dos_drive_prefix
 415 #endif
 416
 417 #ifndef skip_dos_drive_prefix
 418 static inline int git_skip_dos_drive_prefix(char **path)
 419 {
 420         return 0;
 421 }
 422 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 423 #endif
 424
 425 #ifndef is_dir_sep
 426 static inline int git_is_dir_sep(int c)
 427 {
 428         return c == '/';
 429 }
 430 #define is_dir_sep git_is_dir_sep
 431 #endif
 432
 433 #ifndef offset_1st_component
 434 static inline int git_offset_1st_component(const char *path)
 435 {
 436         return is_dir_sep(path[0]);
 437 }
 438 #define offset_1st_component git_offset_1st_component
 439 #endif
 440
 441 #ifndef is_valid_path
 442 #define is_valid_path(path) 1
 443 #endif
 444
 445 #ifndef find_last_dir_sep
 446 static inline char *git_find_last_dir_sep(const char *path)
 447 {
 448         return strrchr(path, '/');
 449 }
 450 #define find_last_dir_sep git_find_last_dir_sep
 451 #endif
 452
 453 #ifndef has_dir_sep
 454 static inline int git_has_dir_sep(const char *path)
 455 {
 456         return !!strchr(path, '/');
 457 }
 458 #define has_dir_sep(path) git_has_dir_sep(path)
 459 #endif
 460
 461 #ifndef query_user_email
 462 #define query_user_email() NULL
 463 #endif
 464
 465 #ifdef __TANDEM
 466 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 467 #include <floss.h(floss_getpwuid)>
 468 #ifndef NSIG
 469 /*
 470  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 471  * known, by detective work using kill -l as a list is all signals
 472  * instead of signal.h where it should be.
 473  */
 474 # define NSIG 100
 475 #endif
 476 #endif
 477
 478 #if defined(__HP_cc) && (__HP_cc >= 61000)
 479 #define NORETURN __attribute__((noreturn))
 480 #define NORETURN_PTR
 481 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 482 #define NORETURN __attribute__((__noreturn__))
 483 #define NORETURN_PTR __attribute__((__noreturn__))
 484 #elif defined(_MSC_VER)
 485 #define NORETURN __declspec(noreturn)
 486 #define NORETURN_PTR
 487 #else
 488 #define NORETURN
 489 #define NORETURN_PTR
 490 #ifndef __GNUC__
 491 #ifndef __attribute__
 492 #define __attribute__(x)
 493 #endif
 494 #endif
 495 #endif
 496
 497 /* The sentinel attribute is valid from gcc version 4.0 */
 498 #if defined(__GNUC__) && (__GNUC__ >= 4)
 499 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 500 #else
 501 #define LAST_ARG_MUST_BE_NULL
 502 #endif
 503
 504 #define MAYBE_UNUSED __attribute__((__unused__))
 505
 506 #include "compat/bswap.h"
 507
 508 #include "wildmatch.h"
 509
 510 struct strbuf;
 511
 512 /* General helper functions */
 513 NORETURN void usage(const char *err);
 514 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 515 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 516 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 517 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
 518 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 519 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 520 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 521 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 522 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 523
 524 #ifndef NO_OPENSSL
 525 #ifdef APPLE_COMMON_CRYPTO
 526 #include "compat/apple-common-crypto.h"
 527 #else
 528 #include <openssl/evp.h>
 529 #include <openssl/hmac.h>
 530 #endif /* APPLE_COMMON_CRYPTO */
 531 #include <openssl/x509v3.h>
 532 #endif /* NO_OPENSSL */
 533
 534 /*
 535  * Let callers be aware of the constant return value; this can help
 536  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 537  * because some compilers may not support variadic macros. Since we're only
 538  * trying to help gcc, anyway, it's OK; other compilers will fall back to
 539  * using the function as usual.
 540  */
 541 #if defined(__GNUC__)
 542 static inline int const_error(void)
 543 {
 544         return -1;
 545 }
 546 #define error(...) (error(__VA_ARGS__), const_error())
 547 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 548 #endif
 549
 550 typedef void (*report_fn)(const char *, va_list params);
 551
 552 void set_die_routine(NORETURN_PTR report_fn routine);
 553 report_fn get_die_message_routine(void);
 554 void set_error_routine(report_fn routine);
 555 report_fn get_error_routine(void);
 556 void set_warn_routine(report_fn routine);
 557 report_fn get_warn_routine(void);
 558 void set_die_is_recursing_routine(int (*routine)(void));
 559
 560 int starts_with(const char *str, const char *prefix);
 561 int istarts_with(const char *str, const char *prefix);
 562
 563 /*
 564  * If the string "str" begins with the string found in "prefix", return 1.
 565  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 566  * the string right after the prefix).
 567  *
 568  * Otherwise, return 0 and leave "out" untouched.
 569  *
 570  * Examples:
 571  *
 572  *   [extract branch name, fail if not a branch]
 573  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 574  *      return -1;
 575  *
 576  *   [skip prefix if present, otherwise use whole string]
 577  *   skip_prefix(name, "refs/heads/", &name);
 578  */
 579 static inline int skip_prefix(const char *str, const char *prefix,
 580                               const char **out)
 581 {
 582         do {
 583                 if (!*prefix) {
 584                         *out = str;
 585                         return 1;
 586                 }
 587         } while (*str++ == *prefix++);
 588         return 0;
 589 }
 590
 591 /*
 592  * If the string "str" is the same as the string in "prefix", then the "arg"
 593  * parameter is set to the "def" parameter and 1 is returned.
 594  * If the string "str" begins with the string found in "prefix" and then a
 595  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 596  * (i.e., to the point in the string right after the prefix and the "=" sign),
 597  * and 1 is returned.
 598  *
 599  * Otherwise, return 0 and leave "arg" untouched.
 600  *
 601  * When we accept both a "--key" and a "--key=<val>" option, this function
 602  * can be used instead of !strcmp(arg, "--key") and then
 603  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 604  */
 605 int skip_to_optional_arg_default(const char *str, const char *prefix,
 606                                  const char **arg, const char *def);
 607
 608 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 609                                        const char **arg)
 610 {
 611         return skip_to_optional_arg_default(str, prefix, arg, "");
 612 }
 613
 614 /*
 615  * Like skip_prefix, but promises never to read past "len" bytes of the input
 616  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 617  */
 618 static inline int skip_prefix_mem(const char *buf, size_t len,
 619                                   const char *prefix,
 620                                   const char **out, size_t *outlen)
 621 {
 622         size_t prefix_len = strlen(prefix);
 623         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 624                 *out = buf + prefix_len;
 625                 *outlen = len - prefix_len;
 626                 return 1;
 627         }
 628         return 0;
 629 }
 630
 631 /*
 632  * If buf ends with suffix, return 1 and subtract the length of the suffix
 633  * from *len. Otherwise, return 0 and leave *len untouched.
 634  */
 635 static inline int strip_suffix_mem(const char *buf, size_t *len,
 636                                    const char *suffix)
 637 {
 638         size_t suflen = strlen(suffix);
 639         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 640                 return 0;
 641         *len -= suflen;
 642         return 1;
 643 }
 644
 645 /*
 646  * If str ends with suffix, return 1 and set *len to the size of the string
 647  * without the suffix. Otherwise, return 0 and set *len to the size of the
 648  * string.
 649  *
 650  * Note that we do _not_ NUL-terminate str to the new length.
 651  */
 652 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 653 {
 654         *len = strlen(str);
 655         return strip_suffix_mem(str, len, suffix);
 656 }
 657
 658 static inline int ends_with(const char *str, const char *suffix)
 659 {
 660         size_t len;
 661         return strip_suffix(str, suffix, &len);
 662 }
 663
 664 #define SWAP(a, b) do {                                         \
 665         void *_swap_a_ptr = &(a);                               \
 666         void *_swap_b_ptr = &(b);                               \
 667         unsigned char _swap_buffer[sizeof(a)];                  \
 668         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 669         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 670                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 671         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 672 } while (0)
 673
 674 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 675
 676 #ifndef PROT_READ
 677 #define PROT_READ 1
 678 #define PROT_WRITE 2
 679 #define MAP_PRIVATE 1
 680 #endif
 681
 682 #define mmap git_mmap
 683 #define munmap git_munmap
 684 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 685 int git_munmap(void *start, size_t length);
 686
 687 #else /* NO_MMAP || USE_WIN32_MMAP */
 688
 689 #include <sys/mman.h>
 690
 691 #endif /* NO_MMAP || USE_WIN32_MMAP */
 692
 693 #ifdef NO_MMAP
 694
 695 /* This value must be multiple of (pagesize * 2) */
 696 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 697
 698 #else /* NO_MMAP */
 699
 700 /* This value must be multiple of (pagesize * 2) */
 701 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 702         (sizeof(void*) >= 8 \
 703                 ?  1 * 1024 * 1024 * 1024 \
 704                 : 32 * 1024 * 1024)
 705
 706 #endif /* NO_MMAP */
 707
 708 #ifndef MAP_FAILED
 709 #define MAP_FAILED ((void *)-1)
 710 #endif
 711
 712 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 713 #define on_disk_bytes(st) ((st).st_size)
 714 #else
 715 #define on_disk_bytes(st) ((st).st_blocks * 512)
 716 #endif
 717
 718 #ifdef NEEDS_MODE_TRANSLATION
 719 #undef S_IFMT
 720 #undef S_IFREG
 721 #undef S_IFDIR
 722 #undef S_IFLNK
 723 #undef S_IFBLK
 724 #undef S_IFCHR
 725 #undef S_IFIFO
 726 #undef S_IFSOCK
 727 #define S_IFMT   0170000
 728 #define S_IFREG  0100000
 729 #define S_IFDIR  0040000
 730 #define S_IFLNK  0120000
 731 #define S_IFBLK  0060000
 732 #define S_IFCHR  0020000
 733 #define S_IFIFO  0010000
 734 #define S_IFSOCK 0140000
 735 #ifdef stat
 736 #undef stat
 737 #endif
 738 #define stat(path, buf) git_stat(path, buf)
 739 int git_stat(const char *, struct stat *);
 740 #ifdef fstat
 741 #undef fstat
 742 #endif
 743 #define fstat(fd, buf) git_fstat(fd, buf)
 744 int git_fstat(int, struct stat *);
 745 #ifdef lstat
 746 #undef lstat
 747 #endif
 748 #define lstat(path, buf) git_lstat(path, buf)
 749 int git_lstat(const char *, struct stat *);
 750 #endif
 751
 752 #define DEFAULT_PACKED_GIT_LIMIT \
 753         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 754
 755 #ifdef NO_PREAD
 756 #define pread git_pread
 757 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 758 #endif
 759 /*
 760  * Forward decl that will remind us if its twin in cache.h changes.
 761  * This function is used in compat/pread.c.  But we can't include
 762  * cache.h there.
 763  */
 764 ssize_t read_in_full(int fd, void *buf, size_t count);
 765
 766 #ifdef NO_SETENV
 767 #define setenv gitsetenv
 768 int gitsetenv(const char *, const char *, int);
 769 #endif
 770
 771 #ifdef NO_MKDTEMP
 772 #define mkdtemp gitmkdtemp
 773 char *gitmkdtemp(char *);
 774 #endif
 775
 776 #ifdef NO_UNSETENV
 777 #define unsetenv gitunsetenv
 778 int gitunsetenv(const char *);
 779 #endif
 780
 781 #ifdef NO_STRCASESTR
 782 #define strcasestr gitstrcasestr
 783 char *gitstrcasestr(const char *haystack, const char *needle);
 784 #endif
 785
 786 #ifdef NO_STRLCPY
 787 #define strlcpy gitstrlcpy
 788 size_t gitstrlcpy(char *, const char *, size_t);
 789 #endif
 790
 791 #ifdef NO_STRTOUMAX
 792 #define strtoumax gitstrtoumax
 793 uintmax_t gitstrtoumax(const char *, char **, int);
 794 #define strtoimax gitstrtoimax
 795 intmax_t gitstrtoimax(const char *, char **, int);
 796 #endif
 797
 798 #ifdef NO_HSTRERROR
 799 #define hstrerror githstrerror
 800 const char *githstrerror(int herror);
 801 #endif
 802
 803 #ifdef NO_MEMMEM
 804 #define memmem gitmemmem
 805 void *gitmemmem(const void *haystack, size_t haystacklen,
 806                 const void *needle, size_t needlelen);
 807 #endif
 808
 809 #ifdef OVERRIDE_STRDUP
 810 #ifdef strdup
 811 #undef strdup
 812 #endif
 813 #define strdup gitstrdup
 814 char *gitstrdup(const char *s);
 815 #endif
 816
 817 #ifdef NO_GETPAGESIZE
 818 #define getpagesize() sysconf(_SC_PAGESIZE)
 819 #endif
 820
 821 #ifndef O_CLOEXEC
 822 #define O_CLOEXEC 0
 823 #endif
 824
 825 #ifdef FREAD_READS_DIRECTORIES
 826 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 827 #  ifdef fopen
 828 #   undef fopen
 829 #  endif
 830 #  define fopen(a,b) git_fopen(a,b)
 831 # endif
 832 FILE *git_fopen(const char*, const char*);
 833 #endif
 834
 835 #ifdef SNPRINTF_RETURNS_BOGUS
 836 #ifdef snprintf
 837 #undef snprintf
 838 #endif
 839 #define snprintf git_snprintf
 840 int git_snprintf(char *str, size_t maxsize,
 841                  const char *format, ...);
 842 #ifdef vsnprintf
 843 #undef vsnprintf
 844 #endif
 845 #define vsnprintf git_vsnprintf
 846 int git_vsnprintf(char *str, size_t maxsize,
 847                   const char *format, va_list ap);
 848 #endif
 849
 850 #ifdef OPEN_RETURNS_EINTR
 851 #undef open
 852 #define open git_open_with_retry
 853 int git_open_with_retry(const char *path, int flag, ...);
 854 #endif
 855
 856 #ifdef __GLIBC_PREREQ
 857 #if __GLIBC_PREREQ(2, 1)
 858 #define HAVE_STRCHRNUL
 859 #endif
 860 #endif
 861
 862 #ifndef HAVE_STRCHRNUL
 863 #define strchrnul gitstrchrnul
 864 static inline char *gitstrchrnul(const char *s, int c)
 865 {
 866         while (*s && *s != c)
 867                 s++;
 868         return (char *)s;
 869 }
 870 #endif
 871
 872 #ifdef NO_INET_PTON
 873 int inet_pton(int af, const char *src, void *dst);
 874 #endif
 875
 876 #ifdef NO_INET_NTOP
 877 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 878 #endif
 879
 880 #ifdef NO_PTHREADS
 881 #define atexit git_atexit
 882 int git_atexit(void (*handler)(void));
 883 #endif
 884
 885 static inline size_t st_add(size_t a, size_t b)
 886 {
 887         if (unsigned_add_overflows(a, b))
 888                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 889                     (uintmax_t)a, (uintmax_t)b);
 890         return a + b;
 891 }
 892 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 893 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 894
 895 static inline size_t st_mult(size_t a, size_t b)
 896 {
 897         if (unsigned_mult_overflows(a, b))
 898                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 899                     (uintmax_t)a, (uintmax_t)b);
 900         return a * b;
 901 }
 902
 903 static inline size_t st_sub(size_t a, size_t b)
 904 {
 905         if (a < b)
 906                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 907                     (uintmax_t)a, (uintmax_t)b);
 908         return a - b;
 909 }
 910
 911 static inline size_t st_left_shift(size_t a, unsigned shift)
 912 {
 913         if (unsigned_left_shift_overflows(a, shift))
 914                 die("size_t overflow: %"PRIuMAX" << %u",
 915                     (uintmax_t)a, shift);
 916         return a << shift;
 917 }
 918
 919 static inline unsigned long cast_size_t_to_ulong(size_t a)
 920 {
 921         if (a != (unsigned long)a)
 922                 die("object too large to read on this platform: %"
 923                     PRIuMAX" is cut off to %lu",
 924                     (uintmax_t)a, (unsigned long)a);
 925         return (unsigned long)a;
 926 }
 927
 928 #ifdef HAVE_ALLOCA_H
 929 # include <alloca.h>
 930 # define xalloca(size)      (alloca(size))
 931 # define xalloca_free(p)    do {} while (0)
 932 #else
 933 # define xalloca(size)      (xmalloc(size))
 934 # define xalloca_free(p)    (free(p))
 935 #endif
 936 char *xstrdup(const char *str);
 937 void *xmalloc(size_t size);
 938 void *xmallocz(size_t size);
 939 void *xmallocz_gently(size_t size);
 940 void *xmemdupz(const void *data, size_t len);
 941 char *xstrndup(const char *str, size_t len);
 942 void *xrealloc(void *ptr, size_t size);
 943 void *xcalloc(size_t nmemb, size_t size);
 944 void xsetenv(const char *name, const char *value, int overwrite);
 945 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 946 const char *mmap_os_err(void);
 947 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 948 int xopen(const char *path, int flags, ...);
 949 ssize_t xread(int fd, void *buf, size_t len);
 950 ssize_t xwrite(int fd, const void *buf, size_t len);
 951 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 952 int xdup(int fd);
 953 FILE *xfopen(const char *path, const char *mode);
 954 FILE *xfdopen(int fd, const char *mode);
 955 int xmkstemp(char *temp_filename);
 956 int xmkstemp_mode(char *temp_filename, int mode);
 957 char *xgetcwd(void);
 958 FILE *fopen_for_writing(const char *path);
 959 FILE *fopen_or_warn(const char *path, const char *mode);
 960
 961 /*
 962  * Like strncmp, but only return zero if s is NUL-terminated and exactly len
 963  * characters long.  If it is not, consider it greater than t.
 964  */
 965 int xstrncmpz(const char *s, const char *t, size_t len);
 966
 967 /*
 968  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 969  * that ptr is used twice, so don't pass e.g. ptr++.
 970  */
 971 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 972
 973 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 974 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
 975 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 976
 977 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 978         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 979 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 980 {
 981         if (n)
 982                 memcpy(dst, src, st_mult(size, n));
 983 }
 984
 985 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
 986         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 987 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
 988 {
 989         if (n)
 990                 memmove(dst, src, st_mult(size, n));
 991 }
 992
 993 /*
 994  * These functions help you allocate structs with flex arrays, and copy
 995  * the data directly into the array. For example, if you had:
 996  *
 997  *   struct foo {
 998  *     int bar;
 999  *     char name[FLEX_ARRAY];
1000  *   };
1001  *
1002  * you can do:
1003  *
1004  *   struct foo *f;
1005  *   FLEX_ALLOC_MEM(f, name, src, len);
1006  *
1007  * to allocate a "foo" with the contents of "src" in the "name" field.
1008  * The resulting struct is automatically zero'd, and the flex-array field
1009  * is NUL-terminated (whether the incoming src buffer was or not).
1010  *
1011  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1012  * but do want to store a pointer to some extra data in the same allocated
1013  * block. For example, if you have:
1014  *
1015  *   struct foo {
1016  *     char *name;
1017  *     int bar;
1018  *   };
1019  *
1020  * you can do:
1021  *
1022  *   struct foo *f;
1023  *   FLEXPTR_ALLOC_STR(f, name, src);
1024  *
1025  * and "name" will point to a block of memory after the struct, which will be
1026  * freed along with the struct (but the pointer can be repointed anywhere).
1027  *
1028  * The *_STR variants accept a string parameter rather than a ptr/len
1029  * combination.
1030  *
1031  * Note that these macros will evaluate the first parameter multiple
1032  * times, and it must be assignable as an lvalue.
1033  */
1034 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1035         size_t flex_array_len_ = (len); \
1036         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1037         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1038 } while (0)
1039 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1040         size_t flex_array_len_ = (len); \
1041         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1042         memcpy((x) + 1, (buf), flex_array_len_); \
1043         (x)->ptrname = (void *)((x)+1); \
1044 } while(0)
1045 #define FLEX_ALLOC_STR(x, flexname, str) \
1046         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1047 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1048         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1049
1050 static inline char *xstrdup_or_null(const char *str)
1051 {
1052         return str ? xstrdup(str) : NULL;
1053 }
1054
1055 static inline size_t xsize_t(off_t len)
1056 {
1057         if (len < 0 || (uintmax_t) len > SIZE_MAX)
1058                 die("Cannot handle files this big");
1059         return (size_t) len;
1060 }
1061
1062 __attribute__((format (printf, 3, 4)))
1063 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1064
1065 #ifndef HOST_NAME_MAX
1066 #define HOST_NAME_MAX 256
1067 #endif
1068
1069 int xgethostname(char *buf, size_t len);
1070
1071 /* in ctype.c, for kwset users */
1072 extern const unsigned char tolower_trans_tbl[256];
1073
1074 /* Sane ctype - no locale, and works with signed chars */
1075 #undef isascii
1076 #undef isspace
1077 #undef isdigit
1078 #undef isalpha
1079 #undef isalnum
1080 #undef isprint
1081 #undef islower
1082 #undef isupper
1083 #undef tolower
1084 #undef toupper
1085 #undef iscntrl
1086 #undef ispunct
1087 #undef isxdigit
1088
1089 extern const unsigned char sane_ctype[256];
1090 #define GIT_SPACE 0x01
1091 #define GIT_DIGIT 0x02
1092 #define GIT_ALPHA 0x04
1093 #define GIT_GLOB_SPECIAL 0x08
1094 #define GIT_REGEX_SPECIAL 0x10
1095 #define GIT_PATHSPEC_MAGIC 0x20
1096 #define GIT_CNTRL 0x40
1097 #define GIT_PUNCT 0x80
1098 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1099 #define isascii(x) (((x) & ~0x7f) == 0)
1100 #define isspace(x) sane_istest(x,GIT_SPACE)
1101 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1102 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1103 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1104 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1105 #define islower(x) sane_iscase(x, 1)
1106 #define isupper(x) sane_iscase(x, 0)
1107 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1108 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1109 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1110 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1111                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1112 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1113 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1114 #define toupper(x) sane_case((unsigned char)(x), 0)
1115 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1116
1117 static inline int sane_case(int x, int high)
1118 {
1119         if (sane_istest(x, GIT_ALPHA))
1120                 x = (x & ~0x20) | high;
1121         return x;
1122 }
1123
1124 static inline int sane_iscase(int x, int is_lower)
1125 {
1126         if (!sane_istest(x, GIT_ALPHA))
1127                 return 0;
1128
1129         if (is_lower)
1130                 return (x & 0x20) != 0;
1131         else
1132                 return (x & 0x20) == 0;
1133 }
1134
1135 /*
1136  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1137  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1138  * locale-specific conversions).
1139  */
1140 static inline int skip_iprefix(const char *str, const char *prefix,
1141                                const char **out)
1142 {
1143         do {
1144                 if (!*prefix) {
1145                         *out = str;
1146                         return 1;
1147                 }
1148         } while (tolower(*str++) == tolower(*prefix++));
1149         return 0;
1150 }
1151
1152 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1153 {
1154         unsigned long ul;
1155         char *p;
1156
1157         errno = 0;
1158         /* negative values would be accepted by strtoul */
1159         if (strchr(s, '-'))
1160                 return -1;
1161         ul = strtoul(s, &p, base);
1162         if (errno || *p || p == s || (unsigned int) ul != ul)
1163                 return -1;
1164         *result = ul;
1165         return 0;
1166 }
1167
1168 static inline int strtol_i(char const *s, int base, int *result)
1169 {
1170         long ul;
1171         char *p;
1172
1173         errno = 0;
1174         ul = strtol(s, &p, base);
1175         if (errno || *p || p == s || (int) ul != ul)
1176                 return -1;
1177         *result = ul;
1178         return 0;
1179 }
1180
1181 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1182                       int(*compar)(const void *, const void *));
1183 #ifdef INTERNAL_QSORT
1184 #define qsort git_stable_qsort
1185 #endif
1186
1187 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1188 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1189                               int(*compar)(const void *, const void *))
1190 {
1191         if (nmemb > 1)
1192                 qsort(base, nmemb, size, compar);
1193 }
1194
1195 #define STABLE_QSORT(base, n, compar) \
1196         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1197
1198 #ifndef HAVE_ISO_QSORT_S
1199 int git_qsort_s(void *base, size_t nmemb, size_t size,
1200                 int (*compar)(const void *, const void *, void *), void *ctx);
1201 #define qsort_s git_qsort_s
1202 #endif
1203
1204 #define QSORT_S(base, n, compar, ctx) do {                      \
1205         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1206                 BUG("qsort_s() failed");                        \
1207 } while (0)
1208
1209 #ifndef REG_STARTEND
1210 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1211 #endif
1212
1213 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1214                               size_t nmatch, regmatch_t pmatch[], int eflags)
1215 {
1216         assert(nmatch > 0 && pmatch);
1217         pmatch[0].rm_so = 0;
1218         pmatch[0].rm_eo = size;
1219         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1220 }
1221
1222 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1223 # define FORCE_DIR_SET_GID S_ISGID
1224 #else
1225 # define FORCE_DIR_SET_GID 0
1226 #endif
1227
1228 #ifdef NO_NSEC
1229 #undef USE_NSEC
1230 #define ST_CTIME_NSEC(st) 0
1231 #define ST_MTIME_NSEC(st) 0
1232 #else
1233 #ifdef USE_ST_TIMESPEC
1234 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1235 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1236 #else
1237 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1238 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1239 #endif
1240 #endif
1241
1242 #ifdef UNRELIABLE_FSTAT
1243 #define fstat_is_reliable() 0
1244 #else
1245 #define fstat_is_reliable() 1
1246 #endif
1247
1248 #ifndef va_copy
1249 /*
1250  * Since an obvious implementation of va_list would be to make it a
1251  * pointer into the stack frame, a simple assignment will work on
1252  * many systems.  But let's try to be more portable.
1253  */
1254 #ifdef __va_copy
1255 #define va_copy(dst, src) __va_copy(dst, src)
1256 #else
1257 #define va_copy(dst, src) ((dst) = (src))
1258 #endif
1259 #endif
1260
1261 /*
1262  * This is always defined as a first step towards making the use of variadic
1263  * macros unconditional. If it causes compilation problems on your platform,
1264  * please report it to the Git mailing list at git@vger.kernel.org.
1265  */
1266 #define HAVE_VARIADIC_MACROS 1
1267
1268 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1269 extern int BUG_exit_code;
1270
1271 #ifdef HAVE_VARIADIC_MACROS
1272 __attribute__((format (printf, 3, 4))) NORETURN
1273 void BUG_fl(const char *file, int line, const char *fmt, ...);
1274 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1275 #else
1276 __attribute__((format (printf, 1, 2))) NORETURN
1277 void BUG(const char *fmt, ...);
1278 #endif
1279
1280 /*
1281  * Preserves errno, prints a message, but gives no warning for ENOENT.
1282  * Returns 0 on success, which includes trying to unlink an object that does
1283  * not exist.
1284  */
1285 int unlink_or_warn(const char *path);
1286  /*
1287   * Tries to unlink file.  Returns 0 if unlink succeeded
1288   * or the file already didn't exist.  Returns -1 and
1289   * appends a message to err suitable for
1290   * 'error("%s", err->buf)' on error.
1291   */
1292 int unlink_or_msg(const char *file, struct strbuf *err);
1293 /*
1294  * Preserves errno, prints a message, but gives no warning for ENOENT.
1295  * Returns 0 on success, which includes trying to remove a directory that does
1296  * not exist.
1297  */
1298 int rmdir_or_warn(const char *path);
1299 /*
1300  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1301  * the supplied file mode.
1302  */
1303 int remove_or_warn(unsigned int mode, const char *path);
1304
1305 /*
1306  * Call access(2), but warn for any error except "missing file"
1307  * (ENOENT or ENOTDIR).
1308  */
1309 #define ACCESS_EACCES_OK (1U << 0)
1310 int access_or_warn(const char *path, int mode, unsigned flag);
1311 int access_or_die(const char *path, int mode, unsigned flag);
1312
1313 /* Warn on an inaccessible file if errno indicates this is an error */
1314 int warn_on_fopen_errors(const char *path);
1315
1316 /*
1317  * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1318  * may be racy. Do not use this as protection against an attacker who can
1319  * simultaneously create paths.
1320  */
1321 int open_nofollow(const char *path, int flags);
1322
1323 #ifndef SHELL_PATH
1324 # define SHELL_PATH "/bin/sh"
1325 #endif
1326
1327 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1328 static inline void flockfile(FILE *fh)
1329 {
1330         ; /* nothing */
1331 }
1332 static inline void funlockfile(FILE *fh)
1333 {
1334         ; /* nothing */
1335 }
1336 #define getc_unlocked(fh) getc(fh)
1337 #endif
1338
1339 #ifdef FILENO_IS_A_MACRO
1340 int git_fileno(FILE *stream);
1341 # ifndef COMPAT_CODE_FILENO
1342 #  undef fileno
1343 #  define fileno(p) git_fileno(p)
1344 # endif
1345 #endif
1346
1347 #ifdef NEED_ACCESS_ROOT_HANDLER
1348 int git_access(const char *path, int mode);
1349 # ifndef COMPAT_CODE_ACCESS
1350 #  ifdef access
1351 #  undef access
1352 #  endif
1353 #  define access(path, mode) git_access(path, mode)
1354 # endif
1355 #endif
1356
1357 /*
1358  * Our code often opens a path to an optional file, to work on its
1359  * contents when we can successfully open it.  We can ignore a failure
1360  * to open if such an optional file does not exist, but we do want to
1361  * report a failure in opening for other reasons (e.g. we got an I/O
1362  * error, or the file is there, but we lack the permission to open).
1363  *
1364  * Call this function after seeing an error from open() or fopen() to
1365  * see if the errno indicates a missing file that we can safely ignore.
1366  */
1367 static inline int is_missing_file_error(int errno_)
1368 {
1369         return (errno_ == ENOENT || errno_ == ENOTDIR);
1370 }
1371
1372 int cmd_main(int, const char **);
1373
1374 /*
1375  * Intercept all calls to exit() and route them to trace2 to
1376  * optionally emit a message before calling the real exit().
1377  */
1378 int trace2_cmd_exit_fl(const char *file, int line, int code);
1379 #define exit(code) exit(trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
1380
1381 /*
1382  * You can mark a stack variable with UNLEAK(var) to avoid it being
1383  * reported as a leak by tools like LSAN or valgrind. The argument
1384  * should generally be the variable itself (not its address and not what
1385  * it points to). It's safe to use this on pointers which may already
1386  * have been freed, or on pointers which may still be in use.
1387  *
1388  * Use this _only_ for a variable that leaks by going out of scope at
1389  * program exit (so only from cmd_* functions or their direct helpers).
1390  * Normal functions, especially those which may be called multiple
1391  * times, should actually free their memory. This is only meant as
1392  * an annotation, and does nothing in non-leak-checking builds.
1393  */
1394 #ifdef SUPPRESS_ANNOTATED_LEAKS
1395 void unleak_memory(const void *ptr, size_t len);
1396 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1397 #else
1398 #define UNLEAK(var) do {} while (0)
1399 #endif
1400
1401 #define z_const
1402 #include <zlib.h>
1403
1404 #if ZLIB_VERNUM < 0x1290
1405 /*
1406  * This is uncompress2, which is only available in zlib >= 1.2.9
1407  * (released as of early 2017). See compat/zlib-uncompress2.c.
1408  */
1409 int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
1410                 uLong *sourceLen);
1411 #endif
1412
1413 /*
1414  * This include must come after system headers, since it introduces macros that
1415  * replace system names.
1416  */
1417 #include "banned.h"
1418
1419 /*
1420  * container_of - Get the address of an object containing a field.
1421  *
1422  * @ptr: pointer to the field.
1423  * @type: type of the object.
1424  * @member: name of the field within the object.
1425  */
1426 #define container_of(ptr, type, member) \
1427         ((type *) ((char *)(ptr) - offsetof(type, member)))
1428
1429 /*
1430  * helper function for `container_of_or_null' to avoid multiple
1431  * evaluation of @ptr
1432  */
1433 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1434 {
1435         return ptr ? (char *)ptr - offset : NULL;
1436 }
1437
1438 /*
1439  * like `container_of', but allows returned value to be NULL
1440  */
1441 #define container_of_or_null(ptr, type, member) \
1442         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1443
1444 /*
1445  * like offsetof(), but takes a pointer to a variable of type which
1446  * contains @member, instead of a specified type.
1447  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1448  * everywhere.
1449  */
1450 #if defined(__GNUC__) /* clang sets this, too */
1451 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1452 #else /* !__GNUC__ */
1453 #define OFFSETOF_VAR(ptr, member) \
1454         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1455 #endif /* !__GNUC__ */
1456
1457 void sleep_millisec(int millisec);
1458
1459 /*
1460  * Generate len bytes from the system cryptographically secure PRNG.
1461  * Returns 0 on success and -1 on error, setting errno.  The inability to
1462  * satisfy the full request is an error.
1463  */
1464 int csprng_bytes(void *buf, size_t len);
1465
1466 #endif