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 void precompose_argv(int argc, const char **argv)
 258 {
 259         ; /* nothing */
 260 }
 261 #define probe_utf8_pathname_composition()
 262 #endif
 263
 264 #ifdef MKDIR_WO_TRAILING_SLASH
 265 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 266 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 267 #endif
 268
 269 #ifdef NO_STRUCT_ITIMERVAL
 270 struct itimerval {
 271         struct timeval it_interval;
 272         struct timeval it_value;
 273 };
 274 #endif
 275
 276 #ifdef NO_SETITIMER
 277 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
 278         return 0; /* pretend success */
 279 }
 280 #endif
 281
 282 #ifndef NO_LIBGEN_H
 283 #include <libgen.h>
 284 #else
 285 #define basename gitbasename
 286 char *gitbasename(char *);
 287 #define dirname gitdirname
 288 char *gitdirname(char *);
 289 #endif
 290
 291 #ifndef NO_ICONV
 292 #include <iconv.h>
 293 #endif
 294
 295 #ifndef NO_OPENSSL
 296 #ifdef __APPLE__
 297 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 298 #include <AvailabilityMacros.h>
 299 #undef DEPRECATED_ATTRIBUTE
 300 #define DEPRECATED_ATTRIBUTE
 301 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 302 #endif
 303 #include <openssl/ssl.h>
 304 #include <openssl/err.h>
 305 #endif
 306
 307 #ifdef HAVE_SYSINFO
 308 # include <sys/sysinfo.h>
 309 #endif
 310
 311 /* On most systems <netdb.h> would have given us this, but
 312  * not on some systems (e.g. z/OS).
 313  */
 314 #ifndef NI_MAXHOST
 315 #define NI_MAXHOST 1025
 316 #endif
 317
 318 #ifndef NI_MAXSERV
 319 #define NI_MAXSERV 32
 320 #endif
 321
 322 /* On most systems <limits.h> would have given us this, but
 323  * not on some systems (e.g. GNU/Hurd).
 324  */
 325 #ifndef PATH_MAX
 326 #define PATH_MAX 4096
 327 #endif
 328
 329 typedef uintmax_t timestamp_t;
 330 #define PRItime PRIuMAX
 331 #define parse_timestamp strtoumax
 332 #define TIME_MAX UINTMAX_MAX
 333 #define TIME_MIN 0
 334
 335 #ifndef PATH_SEP
 336 #define PATH_SEP ':'
 337 #endif
 338
 339 #ifdef HAVE_PATHS_H
 340 #include <paths.h>
 341 #endif
 342 #ifndef _PATH_DEFPATH
 343 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 344 #endif
 345
 346 #ifndef platform_core_config
 347 static inline int noop_core_config(const char *var, const char *value, void *cb)
 348 {
 349         return 0;
 350 }
 351 #define platform_core_config noop_core_config
 352 #endif
 353
 354 int lstat_cache_aware_rmdir(const char *path);
 355 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 356 #define rmdir lstat_cache_aware_rmdir
 357 #endif
 358
 359 #ifndef has_dos_drive_prefix
 360 static inline int git_has_dos_drive_prefix(const char *path)
 361 {
 362         return 0;
 363 }
 364 #define has_dos_drive_prefix git_has_dos_drive_prefix
 365 #endif
 366
 367 #ifndef skip_dos_drive_prefix
 368 static inline int git_skip_dos_drive_prefix(char **path)
 369 {
 370         return 0;
 371 }
 372 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 373 #endif
 374
 375 #ifndef is_dir_sep
 376 static inline int git_is_dir_sep(int c)
 377 {
 378         return c == '/';
 379 }
 380 #define is_dir_sep git_is_dir_sep
 381 #endif
 382
 383 #ifndef offset_1st_component
 384 static inline int git_offset_1st_component(const char *path)
 385 {
 386         return is_dir_sep(path[0]);
 387 }
 388 #define offset_1st_component git_offset_1st_component
 389 #endif
 390
 391 #ifndef is_valid_path
 392 #define is_valid_path(path) 1
 393 #endif
 394
 395 #ifndef is_path_owned_by_current_user
 396
 397 #ifdef __TANDEM
 398 #define ROOT_UID 65535
 399 #else
 400 #define ROOT_UID 0
 401 #endif
 402
 403 /*
 404  * Do not use this function when
 405  * (1) geteuid() did not say we are running as 'root', or
 406  * (2) using this function will compromise the system.
 407  *
 408  * PORTABILITY WARNING:
 409  * This code assumes uid_t is unsigned because that is what sudo does.
 410  * If your uid_t type is signed and all your ids are positive then it
 411  * should all work fine.
 412  * If your version of sudo uses negative values for uid_t or it is
 413  * buggy and return an overflowed value in SUDO_UID, then git might
 414  * fail to grant access to your repository properly or even mistakenly
 415  * grant access to someone else.
 416  * In the unlikely scenario this happened to you, and that is how you
 417  * got to this message, we would like to know about it; so sent us an
 418  * email to git@vger.kernel.org indicating which platform you are
 419  * using and which version of sudo, so we can improve this logic and
 420  * maybe provide you with a patch that would prevent this issue again
 421  * in the future.
 422  */
 423 static inline void extract_id_from_env(const char *env, uid_t *id)
 424 {
 425         const char *real_uid = getenv(env);
 426
 427         /* discard anything empty to avoid a more complex check below */
 428         if (real_uid && *real_uid) {
 429                 char *endptr = NULL;
 430                 unsigned long env_id;
 431
 432                 errno = 0;
 433                 /* silent overflow errors could trigger a bug here */
 434                 env_id = strtoul(real_uid, &endptr, 10);
 435                 if (!*endptr && !errno)
 436                         *id = env_id;
 437         }
 438 }
 439
 440 static inline int is_path_owned_by_current_uid(const char *path)
 441 {
 442         struct stat st;
 443         uid_t euid;
 444
 445         if (lstat(path, &st))
 446                 return 0;
 447
 448         euid = geteuid();
 449         if (euid == ROOT_UID)
 450         {
 451                 if (st.st_uid == ROOT_UID)
 452                         return 1;
 453                 else
 454                         extract_id_from_env("SUDO_UID", &euid);
 455         }
 456
 457         return st.st_uid == euid;
 458 }
 459
 460 #define is_path_owned_by_current_user is_path_owned_by_current_uid
 461 #endif
 462
 463 #ifndef find_last_dir_sep
 464 static inline char *git_find_last_dir_sep(const char *path)
 465 {
 466         return strrchr(path, '/');
 467 }
 468 #define find_last_dir_sep git_find_last_dir_sep
 469 #endif
 470
 471 #ifndef has_dir_sep
 472 static inline int git_has_dir_sep(const char *path)
 473 {
 474         return !!strchr(path, '/');
 475 }
 476 #define has_dir_sep(path) git_has_dir_sep(path)
 477 #endif
 478
 479 #ifndef query_user_email
 480 #define query_user_email() NULL
 481 #endif
 482
 483 #ifdef __TANDEM
 484 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 485 #include <floss.h(floss_getpwuid)>
 486 #ifndef NSIG
 487 /*
 488  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 489  * known, by detective work using kill -l as a list is all signals
 490  * instead of signal.h where it should be.
 491  */
 492 # define NSIG 100
 493 #endif
 494 #endif
 495
 496 #if defined(__HP_cc) && (__HP_cc >= 61000)
 497 #define NORETURN __attribute__((noreturn))
 498 #define NORETURN_PTR
 499 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 500 #define NORETURN __attribute__((__noreturn__))
 501 #define NORETURN_PTR __attribute__((__noreturn__))
 502 #elif defined(_MSC_VER)
 503 #define NORETURN __declspec(noreturn)
 504 #define NORETURN_PTR
 505 #else
 506 #define NORETURN
 507 #define NORETURN_PTR
 508 #ifndef __GNUC__
 509 #ifndef __attribute__
 510 #define __attribute__(x)
 511 #endif
 512 #endif
 513 #endif
 514
 515 /* The sentinel attribute is valid from gcc version 4.0 */
 516 #if defined(__GNUC__) && (__GNUC__ >= 4)
 517 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 518 #else
 519 #define LAST_ARG_MUST_BE_NULL
 520 #endif
 521
 522 #define MAYBE_UNUSED __attribute__((__unused__))
 523
 524 #include "compat/bswap.h"
 525
 526 #include "wildmatch.h"
 527
 528 struct strbuf;
 529
 530 /* General helper functions */
 531 void vreportf(const char *prefix, const char *err, va_list params);
 532 NORETURN void usage(const char *err);
 533 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 534 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 535 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 536 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 537 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 538 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 539 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 540
 541 #ifndef NO_OPENSSL
 542 #ifdef APPLE_COMMON_CRYPTO
 543 #include "compat/apple-common-crypto.h"
 544 #else
 545 #include <openssl/evp.h>
 546 #include <openssl/hmac.h>
 547 #endif /* APPLE_COMMON_CRYPTO */
 548 #include <openssl/x509v3.h>
 549 #endif /* NO_OPENSSL */
 550
 551 /*
 552  * Let callers be aware of the constant return value; this can help
 553  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 554  * because some compilers may not support variadic macros. Since we're only
 555  * trying to help gcc, anyway, it's OK; other compilers will fall back to
 556  * using the function as usual.
 557  */
 558 #if defined(__GNUC__)
 559 static inline int const_error(void)
 560 {
 561         return -1;
 562 }
 563 #define error(...) (error(__VA_ARGS__), const_error())
 564 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 565 #endif
 566
 567 typedef void (*report_fn)(const char *, va_list params);
 568
 569 void set_die_routine(NORETURN_PTR report_fn routine);
 570 void set_error_routine(report_fn routine);
 571 report_fn get_error_routine(void);
 572 void set_warn_routine(report_fn routine);
 573 report_fn get_warn_routine(void);
 574 void set_die_is_recursing_routine(int (*routine)(void));
 575
 576 int starts_with(const char *str, const char *prefix);
 577 int istarts_with(const char *str, const char *prefix);
 578
 579 /*
 580  * If the string "str" begins with the string found in "prefix", return 1.
 581  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 582  * the string right after the prefix).
 583  *
 584  * Otherwise, return 0 and leave "out" untouched.
 585  *
 586  * Examples:
 587  *
 588  *   [extract branch name, fail if not a branch]
 589  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 590  *      return -1;
 591  *
 592  *   [skip prefix if present, otherwise use whole string]
 593  *   skip_prefix(name, "refs/heads/", &name);
 594  */
 595 static inline int skip_prefix(const char *str, const char *prefix,
 596                               const char **out)
 597 {
 598         do {
 599                 if (!*prefix) {
 600                         *out = str;
 601                         return 1;
 602                 }
 603         } while (*str++ == *prefix++);
 604         return 0;
 605 }
 606
 607 /*
 608  * If the string "str" is the same as the string in "prefix", then the "arg"
 609  * parameter is set to the "def" parameter and 1 is returned.
 610  * If the string "str" begins with the string found in "prefix" and then a
 611  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 612  * (i.e., to the point in the string right after the prefix and the "=" sign),
 613  * and 1 is returned.
 614  *
 615  * Otherwise, return 0 and leave "arg" untouched.
 616  *
 617  * When we accept both a "--key" and a "--key=<val>" option, this function
 618  * can be used instead of !strcmp(arg, "--key") and then
 619  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 620  */
 621 int skip_to_optional_arg_default(const char *str, const char *prefix,
 622                                  const char **arg, const char *def);
 623
 624 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 625                                        const char **arg)
 626 {
 627         return skip_to_optional_arg_default(str, prefix, arg, "");
 628 }
 629
 630 /*
 631  * Like skip_prefix, but promises never to read past "len" bytes of the input
 632  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 633  */
 634 static inline int skip_prefix_mem(const char *buf, size_t len,
 635                                   const char *prefix,
 636                                   const char **out, size_t *outlen)
 637 {
 638         size_t prefix_len = strlen(prefix);
 639         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 640                 *out = buf + prefix_len;
 641                 *outlen = len - prefix_len;
 642                 return 1;
 643         }
 644         return 0;
 645 }
 646
 647 /*
 648  * If buf ends with suffix, return 1 and subtract the length of the suffix
 649  * from *len. Otherwise, return 0 and leave *len untouched.
 650  */
 651 static inline int strip_suffix_mem(const char *buf, size_t *len,
 652                                    const char *suffix)
 653 {
 654         size_t suflen = strlen(suffix);
 655         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 656                 return 0;
 657         *len -= suflen;
 658         return 1;
 659 }
 660
 661 /*
 662  * If str ends with suffix, return 1 and set *len to the size of the string
 663  * without the suffix. Otherwise, return 0 and set *len to the size of the
 664  * string.
 665  *
 666  * Note that we do _not_ NUL-terminate str to the new length.
 667  */
 668 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 669 {
 670         *len = strlen(str);
 671         return strip_suffix_mem(str, len, suffix);
 672 }
 673
 674 static inline int ends_with(const char *str, const char *suffix)
 675 {
 676         size_t len;
 677         return strip_suffix(str, suffix, &len);
 678 }
 679
 680 #define SWAP(a, b) do {                                         \
 681         void *_swap_a_ptr = &(a);                               \
 682         void *_swap_b_ptr = &(b);                               \
 683         unsigned char _swap_buffer[sizeof(a)];                  \
 684         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 685         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 686                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 687         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 688 } while (0)
 689
 690 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 691
 692 #ifndef PROT_READ
 693 #define PROT_READ 1
 694 #define PROT_WRITE 2
 695 #define MAP_PRIVATE 1
 696 #endif
 697
 698 #define mmap git_mmap
 699 #define munmap git_munmap
 700 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 701 int git_munmap(void *start, size_t length);
 702
 703 #else /* NO_MMAP || USE_WIN32_MMAP */
 704
 705 #include <sys/mman.h>
 706
 707 #endif /* NO_MMAP || USE_WIN32_MMAP */
 708
 709 #ifdef NO_MMAP
 710
 711 /* This value must be multiple of (pagesize * 2) */
 712 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 713
 714 #else /* NO_MMAP */
 715
 716 /* This value must be multiple of (pagesize * 2) */
 717 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 718         (sizeof(void*) >= 8 \
 719                 ?  1 * 1024 * 1024 * 1024 \
 720                 : 32 * 1024 * 1024)
 721
 722 #endif /* NO_MMAP */
 723
 724 #ifndef MAP_FAILED
 725 #define MAP_FAILED ((void *)-1)
 726 #endif
 727
 728 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 729 #define on_disk_bytes(st) ((st).st_size)
 730 #else
 731 #define on_disk_bytes(st) ((st).st_blocks * 512)
 732 #endif
 733
 734 #ifdef NEEDS_MODE_TRANSLATION
 735 #undef S_IFMT
 736 #undef S_IFREG
 737 #undef S_IFDIR
 738 #undef S_IFLNK
 739 #undef S_IFBLK
 740 #undef S_IFCHR
 741 #undef S_IFIFO
 742 #undef S_IFSOCK
 743 #define S_IFMT   0170000
 744 #define S_IFREG  0100000
 745 #define S_IFDIR  0040000
 746 #define S_IFLNK  0120000
 747 #define S_IFBLK  0060000
 748 #define S_IFCHR  0020000
 749 #define S_IFIFO  0010000
 750 #define S_IFSOCK 0140000
 751 #ifdef stat
 752 #undef stat
 753 #endif
 754 #define stat(path, buf) git_stat(path, buf)
 755 int git_stat(const char *, struct stat *);
 756 #ifdef fstat
 757 #undef fstat
 758 #endif
 759 #define fstat(fd, buf) git_fstat(fd, buf)
 760 int git_fstat(int, struct stat *);
 761 #ifdef lstat
 762 #undef lstat
 763 #endif
 764 #define lstat(path, buf) git_lstat(path, buf)
 765 int git_lstat(const char *, struct stat *);
 766 #endif
 767
 768 #define DEFAULT_PACKED_GIT_LIMIT \
 769         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 770
 771 #ifdef NO_PREAD
 772 #define pread git_pread
 773 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 774 #endif
 775 /*
 776  * Forward decl that will remind us if its twin in cache.h changes.
 777  * This function is used in compat/pread.c.  But we can't include
 778  * cache.h there.
 779  */
 780 ssize_t read_in_full(int fd, void *buf, size_t count);
 781
 782 #ifdef NO_SETENV
 783 #define setenv gitsetenv
 784 int gitsetenv(const char *, const char *, int);
 785 #endif
 786
 787 #ifdef NO_MKDTEMP
 788 #define mkdtemp gitmkdtemp
 789 char *gitmkdtemp(char *);
 790 #endif
 791
 792 #ifdef NO_UNSETENV
 793 #define unsetenv gitunsetenv
 794 void gitunsetenv(const char *);
 795 #endif
 796
 797 #ifdef NO_STRCASESTR
 798 #define strcasestr gitstrcasestr
 799 char *gitstrcasestr(const char *haystack, const char *needle);
 800 #endif
 801
 802 #ifdef NO_STRLCPY
 803 #define strlcpy gitstrlcpy
 804 size_t gitstrlcpy(char *, const char *, size_t);
 805 #endif
 806
 807 #ifdef NO_STRTOUMAX
 808 #define strtoumax gitstrtoumax
 809 uintmax_t gitstrtoumax(const char *, char **, int);
 810 #define strtoimax gitstrtoimax
 811 intmax_t gitstrtoimax(const char *, char **, int);
 812 #endif
 813
 814 #ifdef NO_HSTRERROR
 815 #define hstrerror githstrerror
 816 const char *githstrerror(int herror);
 817 #endif
 818
 819 #ifdef NO_MEMMEM
 820 #define memmem gitmemmem
 821 void *gitmemmem(const void *haystack, size_t haystacklen,
 822                 const void *needle, size_t needlelen);
 823 #endif
 824
 825 #ifdef OVERRIDE_STRDUP
 826 #ifdef strdup
 827 #undef strdup
 828 #endif
 829 #define strdup gitstrdup
 830 char *gitstrdup(const char *s);
 831 #endif
 832
 833 #ifdef NO_GETPAGESIZE
 834 #define getpagesize() sysconf(_SC_PAGESIZE)
 835 #endif
 836
 837 #ifndef O_CLOEXEC
 838 #define O_CLOEXEC 0
 839 #endif
 840
 841 #ifdef FREAD_READS_DIRECTORIES
 842 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 843 #  ifdef fopen
 844 #   undef fopen
 845 #  endif
 846 #  define fopen(a,b) git_fopen(a,b)
 847 # endif
 848 FILE *git_fopen(const char*, const char*);
 849 #endif
 850
 851 #ifdef SNPRINTF_RETURNS_BOGUS
 852 #ifdef snprintf
 853 #undef snprintf
 854 #endif
 855 #define snprintf git_snprintf
 856 int git_snprintf(char *str, size_t maxsize,
 857                  const char *format, ...);
 858 #ifdef vsnprintf
 859 #undef vsnprintf
 860 #endif
 861 #define vsnprintf git_vsnprintf
 862 int git_vsnprintf(char *str, size_t maxsize,
 863                   const char *format, va_list ap);
 864 #endif
 865
 866 #ifdef __GLIBC_PREREQ
 867 #if __GLIBC_PREREQ(2, 1)
 868 #define HAVE_STRCHRNUL
 869 #endif
 870 #endif
 871
 872 #ifndef HAVE_STRCHRNUL
 873 #define strchrnul gitstrchrnul
 874 static inline char *gitstrchrnul(const char *s, int c)
 875 {
 876         while (*s && *s != c)
 877                 s++;
 878         return (char *)s;
 879 }
 880 #endif
 881
 882 #ifdef NO_INET_PTON
 883 int inet_pton(int af, const char *src, void *dst);
 884 #endif
 885
 886 #ifdef NO_INET_NTOP
 887 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 888 #endif
 889
 890 #ifdef NO_PTHREADS
 891 #define atexit git_atexit
 892 int git_atexit(void (*handler)(void));
 893 #endif
 894
 895 static inline size_t st_add(size_t a, size_t b)
 896 {
 897         if (unsigned_add_overflows(a, b))
 898                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 899                     (uintmax_t)a, (uintmax_t)b);
 900         return a + b;
 901 }
 902 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 903 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 904
 905 static inline size_t st_mult(size_t a, size_t b)
 906 {
 907         if (unsigned_mult_overflows(a, b))
 908                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 909                     (uintmax_t)a, (uintmax_t)b);
 910         return a * b;
 911 }
 912
 913 static inline size_t st_sub(size_t a, size_t b)
 914 {
 915         if (a < b)
 916                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 917                     (uintmax_t)a, (uintmax_t)b);
 918         return a - b;
 919 }
 920
 921 #ifdef HAVE_ALLOCA_H
 922 # include <alloca.h>
 923 # define xalloca(size)      (alloca(size))
 924 # define xalloca_free(p)    do {} while (0)
 925 #else
 926 # define xalloca(size)      (xmalloc(size))
 927 # define xalloca_free(p)    (free(p))
 928 #endif
 929 char *xstrdup(const char *str);
 930 void *xmalloc(size_t size);
 931 void *xmallocz(size_t size);
 932 void *xmallocz_gently(size_t size);
 933 void *xmemdupz(const void *data, size_t len);
 934 char *xstrndup(const char *str, size_t len);
 935 void *xrealloc(void *ptr, size_t size);
 936 void *xcalloc(size_t nmemb, size_t size);
 937 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 938 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 939 int xopen(const char *path, int flags, ...);
 940 ssize_t xread(int fd, void *buf, size_t len);
 941 ssize_t xwrite(int fd, const void *buf, size_t len);
 942 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 943 int xdup(int fd);
 944 FILE *xfopen(const char *path, const char *mode);
 945 FILE *xfdopen(int fd, const char *mode);
 946 int xmkstemp(char *temp_filename);
 947 int xmkstemp_mode(char *temp_filename, int mode);
 948 char *xgetcwd(void);
 949 FILE *fopen_for_writing(const char *path);
 950 FILE *fopen_or_warn(const char *path, const char *mode);
 951
 952 /*
 953  * Like strncmp, but only return zero if s is NUL-terminated and exactly len
 954  * characters long.  If it is not, consider it greater than t.
 955  */
 956 int xstrncmpz(const char *s, const char *t, size_t len);
 957
 958 /*
 959  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 960  * that ptr is used twice, so don't pass e.g. ptr++.
 961  */
 962 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 963
 964 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 965 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)));
 966 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 967
 968 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 969         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 970 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 971 {
 972         if (n)
 973                 memcpy(dst, src, st_mult(size, n));
 974 }
 975
 976 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
 977         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 978 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
 979 {
 980         if (n)
 981                 memmove(dst, src, st_mult(size, n));
 982 }
 983
 984 /*
 985  * These functions help you allocate structs with flex arrays, and copy
 986  * the data directly into the array. For example, if you had:
 987  *
 988  *   struct foo {
 989  *     int bar;
 990  *     char name[FLEX_ARRAY];
 991  *   };
 992  *
 993  * you can do:
 994  *
 995  *   struct foo *f;
 996  *   FLEX_ALLOC_MEM(f, name, src, len);
 997  *
 998  * to allocate a "foo" with the contents of "src" in the "name" field.
 999  * The resulting struct is automatically zero'd, and the flex-array field
1000  * is NUL-terminated (whether the incoming src buffer was or not).
1001  *
1002  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1003  * but do want to store a pointer to some extra data in the same allocated
1004  * block. For example, if you have:
1005  *
1006  *   struct foo {
1007  *     char *name;
1008  *     int bar;
1009  *   };
1010  *
1011  * you can do:
1012  *
1013  *   struct foo *f;
1014  *   FLEXPTR_ALLOC_STR(f, name, src);
1015  *
1016  * and "name" will point to a block of memory after the struct, which will be
1017  * freed along with the struct (but the pointer can be repointed anywhere).
1018  *
1019  * The *_STR variants accept a string parameter rather than a ptr/len
1020  * combination.
1021  *
1022  * Note that these macros will evaluate the first parameter multiple
1023  * times, and it must be assignable as an lvalue.
1024  */
1025 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1026         size_t flex_array_len_ = (len); \
1027         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1028         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1029 } while (0)
1030 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1031         size_t flex_array_len_ = (len); \
1032         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1033         memcpy((x) + 1, (buf), flex_array_len_); \
1034         (x)->ptrname = (void *)((x)+1); \
1035 } while(0)
1036 #define FLEX_ALLOC_STR(x, flexname, str) \
1037         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1038 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1039         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1040
1041 static inline char *xstrdup_or_null(const char *str)
1042 {
1043         return str ? xstrdup(str) : NULL;
1044 }
1045
1046 static inline size_t xsize_t(off_t len)
1047 {
1048         size_t size = (size_t) len;
1049
1050         if (len != (off_t) size)
1051                 die("Cannot handle files this big");
1052         return size;
1053 }
1054
1055 __attribute__((format (printf, 3, 4)))
1056 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1057
1058 #ifndef HOST_NAME_MAX
1059 #define HOST_NAME_MAX 256
1060 #endif
1061
1062 int xgethostname(char *buf, size_t len);
1063
1064 /* in ctype.c, for kwset users */
1065 extern const unsigned char tolower_trans_tbl[256];
1066
1067 /* Sane ctype - no locale, and works with signed chars */
1068 #undef isascii
1069 #undef isspace
1070 #undef isdigit
1071 #undef isalpha
1072 #undef isalnum
1073 #undef isprint
1074 #undef islower
1075 #undef isupper
1076 #undef tolower
1077 #undef toupper
1078 #undef iscntrl
1079 #undef ispunct
1080 #undef isxdigit
1081
1082 extern const unsigned char sane_ctype[256];
1083 #define GIT_SPACE 0x01
1084 #define GIT_DIGIT 0x02
1085 #define GIT_ALPHA 0x04
1086 #define GIT_GLOB_SPECIAL 0x08
1087 #define GIT_REGEX_SPECIAL 0x10
1088 #define GIT_PATHSPEC_MAGIC 0x20
1089 #define GIT_CNTRL 0x40
1090 #define GIT_PUNCT 0x80
1091 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1092 #define isascii(x) (((x) & ~0x7f) == 0)
1093 #define isspace(x) sane_istest(x,GIT_SPACE)
1094 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1095 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1096 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1097 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1098 #define islower(x) sane_iscase(x, 1)
1099 #define isupper(x) sane_iscase(x, 0)
1100 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1101 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1102 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1103 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1104                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1105 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1106 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1107 #define toupper(x) sane_case((unsigned char)(x), 0)
1108 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1109
1110 static inline int sane_case(int x, int high)
1111 {
1112         if (sane_istest(x, GIT_ALPHA))
1113                 x = (x & ~0x20) | high;
1114         return x;
1115 }
1116
1117 static inline int sane_iscase(int x, int is_lower)
1118 {
1119         if (!sane_istest(x, GIT_ALPHA))
1120                 return 0;
1121
1122         if (is_lower)
1123                 return (x & 0x20) != 0;
1124         else
1125                 return (x & 0x20) == 0;
1126 }
1127
1128 /*
1129  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1130  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1131  * locale-specific conversions).
1132  */
1133 static inline int skip_iprefix(const char *str, const char *prefix,
1134                                const char **out)
1135 {
1136         do {
1137                 if (!*prefix) {
1138                         *out = str;
1139                         return 1;
1140                 }
1141         } while (tolower(*str++) == tolower(*prefix++));
1142         return 0;
1143 }
1144
1145 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1146 {
1147         unsigned long ul;
1148         char *p;
1149
1150         errno = 0;
1151         /* negative values would be accepted by strtoul */
1152         if (strchr(s, '-'))
1153                 return -1;
1154         ul = strtoul(s, &p, base);
1155         if (errno || *p || p == s || (unsigned int) ul != ul)
1156                 return -1;
1157         *result = ul;
1158         return 0;
1159 }
1160
1161 static inline int strtol_i(char const *s, int base, int *result)
1162 {
1163         long ul;
1164         char *p;
1165
1166         errno = 0;
1167         ul = strtol(s, &p, base);
1168         if (errno || *p || p == s || (int) ul != ul)
1169                 return -1;
1170         *result = ul;
1171         return 0;
1172 }
1173
1174 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1175                       int(*compar)(const void *, const void *));
1176 #ifdef INTERNAL_QSORT
1177 #define qsort git_stable_qsort
1178 #endif
1179
1180 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1181 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1182                               int(*compar)(const void *, const void *))
1183 {
1184         if (nmemb > 1)
1185                 qsort(base, nmemb, size, compar);
1186 }
1187
1188 #define STABLE_QSORT(base, n, compar) \
1189         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1190
1191 #ifndef HAVE_ISO_QSORT_S
1192 int git_qsort_s(void *base, size_t nmemb, size_t size,
1193                 int (*compar)(const void *, const void *, void *), void *ctx);
1194 #define qsort_s git_qsort_s
1195 #endif
1196
1197 #define QSORT_S(base, n, compar, ctx) do {                      \
1198         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1199                 BUG("qsort_s() failed");                        \
1200 } while (0)
1201
1202 #ifndef REG_STARTEND
1203 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1204 #endif
1205
1206 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1207                               size_t nmatch, regmatch_t pmatch[], int eflags)
1208 {
1209         assert(nmatch > 0 && pmatch);
1210         pmatch[0].rm_so = 0;
1211         pmatch[0].rm_eo = size;
1212         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1213 }
1214
1215 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1216 # define FORCE_DIR_SET_GID S_ISGID
1217 #else
1218 # define FORCE_DIR_SET_GID 0
1219 #endif
1220
1221 #ifdef NO_NSEC
1222 #undef USE_NSEC
1223 #define ST_CTIME_NSEC(st) 0
1224 #define ST_MTIME_NSEC(st) 0
1225 #else
1226 #ifdef USE_ST_TIMESPEC
1227 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1228 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1229 #else
1230 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1231 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1232 #endif
1233 #endif
1234
1235 #ifdef UNRELIABLE_FSTAT
1236 #define fstat_is_reliable() 0
1237 #else
1238 #define fstat_is_reliable() 1
1239 #endif
1240
1241 #ifndef va_copy
1242 /*
1243  * Since an obvious implementation of va_list would be to make it a
1244  * pointer into the stack frame, a simple assignment will work on
1245  * many systems.  But let's try to be more portable.
1246  */
1247 #ifdef __va_copy
1248 #define va_copy(dst, src) __va_copy(dst, src)
1249 #else
1250 #define va_copy(dst, src) ((dst) = (src))
1251 #endif
1252 #endif
1253
1254 #if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
1255 #define HAVE_VARIADIC_MACROS 1
1256 #endif
1257
1258 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1259 extern int BUG_exit_code;
1260
1261 #ifdef HAVE_VARIADIC_MACROS
1262 __attribute__((format (printf, 3, 4))) NORETURN
1263 void BUG_fl(const char *file, int line, const char *fmt, ...);
1264 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1265 #else
1266 __attribute__((format (printf, 1, 2))) NORETURN
1267 void BUG(const char *fmt, ...);
1268 #endif
1269
1270 /*
1271  * Preserves errno, prints a message, but gives no warning for ENOENT.
1272  * Returns 0 on success, which includes trying to unlink an object that does
1273  * not exist.
1274  */
1275 int unlink_or_warn(const char *path);
1276  /*
1277   * Tries to unlink file.  Returns 0 if unlink succeeded
1278   * or the file already didn't exist.  Returns -1 and
1279   * appends a message to err suitable for
1280   * 'error("%s", err->buf)' on error.
1281   */
1282 int unlink_or_msg(const char *file, struct strbuf *err);
1283 /*
1284  * Preserves errno, prints a message, but gives no warning for ENOENT.
1285  * Returns 0 on success, which includes trying to remove a directory that does
1286  * not exist.
1287  */
1288 int rmdir_or_warn(const char *path);
1289 /*
1290  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1291  * the supplied file mode.
1292  */
1293 int remove_or_warn(unsigned int mode, const char *path);
1294
1295 /*
1296  * Call access(2), but warn for any error except "missing file"
1297  * (ENOENT or ENOTDIR).
1298  */
1299 #define ACCESS_EACCES_OK (1U << 0)
1300 int access_or_warn(const char *path, int mode, unsigned flag);
1301 int access_or_die(const char *path, int mode, unsigned flag);
1302
1303 /* Warn on an inaccessible file if errno indicates this is an error */
1304 int warn_on_fopen_errors(const char *path);
1305
1306 #if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1307 #define USE_PARENS_AROUND_GETTEXT_N 1
1308 #endif
1309
1310 #ifndef SHELL_PATH
1311 # define SHELL_PATH "/bin/sh"
1312 #endif
1313
1314 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1315 static inline void flockfile(FILE *fh)
1316 {
1317         ; /* nothing */
1318 }
1319 static inline void funlockfile(FILE *fh)
1320 {
1321         ; /* nothing */
1322 }
1323 #define getc_unlocked(fh) getc(fh)
1324 #endif
1325
1326 #ifdef FILENO_IS_A_MACRO
1327 int git_fileno(FILE *stream);
1328 # ifndef COMPAT_CODE_FILENO
1329 #  undef fileno
1330 #  define fileno(p) git_fileno(p)
1331 # endif
1332 #endif
1333
1334 #ifdef NEED_ACCESS_ROOT_HANDLER
1335 int git_access(const char *path, int mode);
1336 # ifndef COMPAT_CODE_ACCESS
1337 #  ifdef access
1338 #  undef access
1339 #  endif
1340 #  define access(path, mode) git_access(path, mode)
1341 # endif
1342 #endif
1343
1344 /*
1345  * Our code often opens a path to an optional file, to work on its
1346  * contents when we can successfully open it.  We can ignore a failure
1347  * to open if such an optional file does not exist, but we do want to
1348  * report a failure in opening for other reasons (e.g. we got an I/O
1349  * error, or the file is there, but we lack the permission to open).
1350  *
1351  * Call this function after seeing an error from open() or fopen() to
1352  * see if the errno indicates a missing file that we can safely ignore.
1353  */
1354 static inline int is_missing_file_error(int errno_)
1355 {
1356         return (errno_ == ENOENT || errno_ == ENOTDIR);
1357 }
1358
1359 int cmd_main(int, const char **);
1360
1361 /*
1362  * Intercept all calls to exit() and route them to trace2 to
1363  * optionally emit a message before calling the real exit().
1364  */
1365 int trace2_cmd_exit_fl(const char *file, int line, int code);
1366 #define exit(code) exit(trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
1367
1368 /*
1369  * You can mark a stack variable with UNLEAK(var) to avoid it being
1370  * reported as a leak by tools like LSAN or valgrind. The argument
1371  * should generally be the variable itself (not its address and not what
1372  * it points to). It's safe to use this on pointers which may already
1373  * have been freed, or on pointers which may still be in use.
1374  *
1375  * Use this _only_ for a variable that leaks by going out of scope at
1376  * program exit (so only from cmd_* functions or their direct helpers).
1377  * Normal functions, especially those which may be called multiple
1378  * times, should actually free their memory. This is only meant as
1379  * an annotation, and does nothing in non-leak-checking builds.
1380  */
1381 #ifdef SUPPRESS_ANNOTATED_LEAKS
1382 void unleak_memory(const void *ptr, size_t len);
1383 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1384 #else
1385 #define UNLEAK(var) do {} while (0)
1386 #endif
1387
1388 /*
1389  * This include must come after system headers, since it introduces macros that
1390  * replace system names.
1391  */
1392 #include "banned.h"
1393
1394 /*
1395  * container_of - Get the address of an object containing a field.
1396  *
1397  * @ptr: pointer to the field.
1398  * @type: type of the object.
1399  * @member: name of the field within the object.
1400  */
1401 #define container_of(ptr, type, member) \
1402         ((type *) ((char *)(ptr) - offsetof(type, member)))
1403
1404 /*
1405  * helper function for `container_of_or_null' to avoid multiple
1406  * evaluation of @ptr
1407  */
1408 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1409 {
1410         return ptr ? (char *)ptr - offset : NULL;
1411 }
1412
1413 /*
1414  * like `container_of', but allows returned value to be NULL
1415  */
1416 #define container_of_or_null(ptr, type, member) \
1417         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1418
1419 /*
1420  * like offsetof(), but takes a pointer to a a variable of type which
1421  * contains @member, instead of a specified type.
1422  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1423  * everywhere.
1424  */
1425 #if defined(__GNUC__) /* clang sets this, too */
1426 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1427 #else /* !__GNUC__ */
1428 #define OFFSETOF_VAR(ptr, member) \
1429         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1430 #endif /* !__GNUC__ */
1431
1432 void sleep_millisec(int millisec);
1433
1434 #endif