git-compat-util.h

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