git-compat-util.h

   1 #ifndef GIT_COMPAT_UTIL_H
   2 #define GIT_COMPAT_UTIL_H
   3
   4 #if __STDC_VERSION__ - 0 < 199901L
   5 /*
   6  * Git is in a testing period for mandatory C99 support in the compiler.  If
   7  * your compiler is reasonably recent, you can try to enable C99 support (or,
   8  * for MSVC, C11 support).  If you encounter a problem and can't enable C99
   9  * support with your compiler (such as with "-std=gnu99") and don't have access
  10  * to one with this support, such as GCC or Clang, you can remove this #if
  11  * directive, but please report the details of your system to
  12  * git@vger.kernel.org.
  13  */
  14 #error "Required C99 support is in a test phase.  Please see git-compat-util.h for more details."
  15 #endif
  16
  17 #ifdef USE_MSVC_CRTDBG
  18 /*
  19  * For these to work they must appear very early in each
  20  * file -- before most of the standard header files.
  21  */
  22 #include <stdlib.h>
  23 #include <crtdbg.h>
  24 #endif
  25
  26 struct strbuf;
  27
  28
  29 #define _FILE_OFFSET_BITS 64
  30
  31
  32 /* Derived from Linux "Features Test Macro" header
  33  * Convenience macros to test the versions of gcc (or
  34  * a compatible compiler).
  35  * Use them like this:
  36  *  #if GIT_GNUC_PREREQ (2,8)
  37  *   ... code requiring gcc 2.8 or later ...
  38  *  #endif
  39 */
  40 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  41 # define GIT_GNUC_PREREQ(maj, min) \
  42         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  43 #else
  44  #define GIT_GNUC_PREREQ(maj, min) 0
  45 #endif
  46
  47
  48 #ifndef FLEX_ARRAY
  49 /*
  50  * See if our compiler is known to support flexible array members.
  51  */
  52
  53 /*
  54  * Check vendor specific quirks first, before checking the
  55  * __STDC_VERSION__, as vendor compilers can lie and we need to be
  56  * able to work them around.  Note that by not defining FLEX_ARRAY
  57  * here, we can fall back to use the "safer but a bit wasteful" one
  58  * later.
  59  */
  60 #if defined(__SUNPRO_C) && (__SUNPRO_C <= 0x580)
  61 #elif defined(__GNUC__)
  62 # if (__GNUC__ >= 3)
  63 #  define FLEX_ARRAY /* empty */
  64 # else
  65 #  define FLEX_ARRAY 0 /* older GNU extension */
  66 # endif
  67 #elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
  68 # define FLEX_ARRAY /* empty */
  69 #endif
  70
  71 /*
  72  * Otherwise, default to safer but a bit wasteful traditional style
  73  */
  74 #ifndef FLEX_ARRAY
  75 # define FLEX_ARRAY 1
  76 #endif
  77 #endif
  78
  79
  80 /*
  81  * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
  82  * @cond: the compile-time condition which must be true.
  83  *
  84  * Your compile will fail if the condition isn't true, or can't be evaluated
  85  * by the compiler.  This can be used in an expression: its value is "0".
  86  *
  87  * Example:
  88  *      #define foo_to_char(foo)                                        \
  89  *               ((char *)(foo)                                         \
  90  *                + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
  91  */
  92 #define BUILD_ASSERT_OR_ZERO(cond) \
  93         (sizeof(char [1 - 2*!(cond)]) - 1)
  94
  95 #if GIT_GNUC_PREREQ(3, 1)
  96  /* &arr[0] degrades to a pointer: a different type from an array */
  97 # define BARF_UNLESS_AN_ARRAY(arr)                                              \
  98         BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
  99                                                            __typeof__(&(arr)[0])))
 100 #else
 101 # define BARF_UNLESS_AN_ARRAY(arr) 0
 102 #endif
 103 /*
 104  * ARRAY_SIZE - get the number of elements in a visible array
 105  * @x: the array whose size you want.
 106  *
 107  * This does not work on pointers, or arrays declared as [], or
 108  * function parameters.  With correct compiler support, such usage
 109  * will cause a build error (see the build_assert_or_zero macro).
 110  */
 111 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
 112
 113 #define bitsizeof(x)  (CHAR_BIT * sizeof(x))
 114
 115 #define maximum_signed_value_of_type(a) \
 116     (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
 117
 118 #define maximum_unsigned_value_of_type(a) \
 119     (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
 120
 121 /*
 122  * Signed integer overflow is undefined in C, so here's a helper macro
 123  * to detect if the sum of two integers will overflow.
 124  *
 125  * Requires: a >= 0, typeof(a) equals typeof(b)
 126  */
 127 #define signed_add_overflows(a, b) \
 128     ((b) > maximum_signed_value_of_type(a) - (a))
 129
 130 #define unsigned_add_overflows(a, b) \
 131     ((b) > maximum_unsigned_value_of_type(a) - (a))
 132
 133 /*
 134  * Returns true if the multiplication of "a" and "b" will
 135  * overflow. The types of "a" and "b" must match and must be unsigned.
 136  * Note that this macro evaluates "a" twice!
 137  */
 138 #define unsigned_mult_overflows(a, b) \
 139     ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
 140
 141 /*
 142  * Returns true if the left shift of "a" by "shift" bits will
 143  * overflow. The type of "a" must be unsigned.
 144  */
 145 #define unsigned_left_shift_overflows(a, shift) \
 146     ((shift) < bitsizeof(a) && \
 147      (a) > maximum_unsigned_value_of_type(a) >> (shift))
 148
 149 #ifdef __GNUC__
 150 #define TYPEOF(x) (__typeof__(x))
 151 #else
 152 #define TYPEOF(x)
 153 #endif
 154
 155 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 156 #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 157
 158 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 159
 160 /* Approximation of the length of the decimal representation of this type. */
 161 #define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 162
 163 #ifdef __MINGW64__
 164 #define _POSIX_C_SOURCE 1
 165 #elif defined(__sun__)
 166  /*
 167   * On Solaris, when _XOPEN_EXTENDED is set, its header file
 168   * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 169   * setting to say we are XPG5 or XPG6.  Also on Solaris,
 170   * XPG6 programs must be compiled with a c99 compiler, while
 171   * non XPG6 programs must be compiled with a pre-c99 compiler.
 172   */
 173 # if __STDC_VERSION__ - 0 >= 199901L
 174 # define _XOPEN_SOURCE 600
 175 # else
 176 # define _XOPEN_SOURCE 500
 177 # endif
 178 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 179       !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 180       !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
 181       !defined(__CYGWIN__)
 182 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 183 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 184 #endif
 185 #define _ALL_SOURCE 1
 186 #define _GNU_SOURCE 1
 187 #define _BSD_SOURCE 1
 188 #define _DEFAULT_SOURCE 1
 189 #define _NETBSD_SOURCE 1
 190 #define _SGI_SOURCE 1
 191
 192 #if GIT_GNUC_PREREQ(4, 5)
 193 #define UNUSED __attribute__((unused)) \
 194         __attribute__((deprecated ("parameter declared as UNUSED")))
 195 #elif defined(__GNUC__)
 196 #define UNUSED __attribute__((unused)) \
 197         __attribute__((deprecated))
 198 #else
 199 #define UNUSED
 200 #endif
 201
 202 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 203 # if !defined(_WIN32_WINNT)
 204 #  define _WIN32_WINNT 0x0600
 205 # endif
 206 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 207 #include <winsock2.h>
 208 #ifndef NO_UNIX_SOCKETS
 209 #include <afunix.h>
 210 #endif
 211 #include <windows.h>
 212 #define GIT_WINDOWS_NATIVE
 213 #endif
 214
 215 #include <unistd.h>
 216 #include <stdio.h>
 217 #include <sys/stat.h>
 218 #include <fcntl.h>
 219 #include <stddef.h>
 220 #include <stdlib.h>
 221 #include <stdarg.h>
 222 #include <string.h>
 223 #ifdef HAVE_STRINGS_H
 224 #include <strings.h> /* for strcasecmp() */
 225 #endif
 226 #include <errno.h>
 227 #include <limits.h>
 228 #ifdef NEEDS_SYS_PARAM_H
 229 #include <sys/param.h>
 230 #endif
 231 #include <sys/types.h>
 232 #include <dirent.h>
 233 #include <sys/time.h>
 234 #include <time.h>
 235 #include <signal.h>
 236 #include <assert.h>
 237 #include <regex.h>
 238 #include <utime.h>
 239 #include <syslog.h>
 240 #if !defined(NO_POLL_H)
 241 #include <poll.h>
 242 #elif !defined(NO_SYS_POLL_H)
 243 #include <sys/poll.h>
 244 #else
 245 /* Pull the compat stuff */
 246 #include <poll.h>
 247 #endif
 248 #ifdef HAVE_BSD_SYSCTL
 249 #include <sys/sysctl.h>
 250 #endif
 251
 252 /* Used by compat/win32/path-utils.h, and more */
 253 static inline int is_xplatform_dir_sep(int c)
 254 {
 255         return c == '/' || c == '\\';
 256 }
 257
 258 #if defined(__CYGWIN__)
 259 #include "compat/win32/path-utils.h"
 260 #endif
 261 #if defined(__MINGW32__)
 262 /* pull in Windows compatibility stuff */
 263 #include "compat/win32/path-utils.h"
 264 #include "compat/mingw.h"
 265 #elif defined(_MSC_VER)
 266 #include "compat/win32/path-utils.h"
 267 #include "compat/msvc.h"
 268 #else
 269 #include <sys/utsname.h>
 270 #include <sys/wait.h>
 271 #include <sys/resource.h>
 272 #include <sys/socket.h>
 273 #include <sys/ioctl.h>
 274 #include <sys/statvfs.h>
 275 #include <termios.h>
 276 #ifndef NO_SYS_SELECT_H
 277 #include <sys/select.h>
 278 #endif
 279 #include <netinet/in.h>
 280 #include <netinet/tcp.h>
 281 #include <arpa/inet.h>
 282 #include <netdb.h>
 283 #include <pwd.h>
 284 #include <sys/un.h>
 285 #ifndef NO_INTTYPES_H
 286 #include <inttypes.h>
 287 #else
 288 #include <stdint.h>
 289 #endif
 290 #ifdef HAVE_ARC4RANDOM_LIBBSD
 291 #include <bsd/stdlib.h>
 292 #endif
 293 #ifdef HAVE_GETRANDOM
 294 #include <sys/random.h>
 295 #endif
 296 #ifdef NO_INTPTR_T
 297 /*
 298  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 299  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 300  * while on IP16 and IP16L32 it is "int" (resp. "short")
 301  * Size needs to match (or exceed) 'sizeof(void *)'.
 302  * We can't take "long long" here as not everybody has it.
 303  */
 304 typedef long intptr_t;
 305 typedef unsigned long uintptr_t;
 306 #endif
 307 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 308 #include <grp.h>
 309 #define _ALL_SOURCE 1
 310 #endif
 311
 312 /* used on Mac OS X */
 313 #ifdef PRECOMPOSE_UNICODE
 314 #include "compat/precompose_utf8.h"
 315 #else
 316 static inline const char *precompose_argv_prefix(int argc, const char **argv, const char *prefix)
 317 {
 318         return prefix;
 319 }
 320 static inline const char *precompose_string_if_needed(const char *in)
 321 {
 322         return in;
 323 }
 324
 325 #define probe_utf8_pathname_composition()
 326 #endif
 327
 328 #ifdef MKDIR_WO_TRAILING_SLASH
 329 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 330 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 331 #endif
 332
 333 #ifdef NO_STRUCT_ITIMERVAL
 334 struct itimerval {
 335         struct timeval it_interval;
 336         struct timeval it_value;
 337 };
 338 #endif
 339
 340 #ifdef NO_SETITIMER
 341 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
 342         return 0; /* pretend success */
 343 }
 344 #endif
 345
 346 #ifndef NO_LIBGEN_H
 347 #include <libgen.h>
 348 #else
 349 #define basename gitbasename
 350 char *gitbasename(char *);
 351 #define dirname gitdirname
 352 char *gitdirname(char *);
 353 #endif
 354
 355 #ifndef NO_ICONV
 356 #include <iconv.h>
 357 #endif
 358
 359 #ifndef NO_OPENSSL
 360 #ifdef __APPLE__
 361 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 362 #include <AvailabilityMacros.h>
 363 #undef DEPRECATED_ATTRIBUTE
 364 #define DEPRECATED_ATTRIBUTE
 365 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 366 #endif
 367 #include <openssl/ssl.h>
 368 #include <openssl/err.h>
 369 #endif
 370
 371 #ifdef HAVE_SYSINFO
 372 # include <sys/sysinfo.h>
 373 #endif
 374
 375 /* On most systems <netdb.h> would have given us this, but
 376  * not on some systems (e.g. z/OS).
 377  */
 378 #ifndef NI_MAXHOST
 379 #define NI_MAXHOST 1025
 380 #endif
 381
 382 #ifndef NI_MAXSERV
 383 #define NI_MAXSERV 32
 384 #endif
 385
 386 /* On most systems <limits.h> would have given us this, but
 387  * not on some systems (e.g. GNU/Hurd).
 388  */
 389 #ifndef PATH_MAX
 390 #define PATH_MAX 4096
 391 #endif
 392
 393 typedef uintmax_t timestamp_t;
 394 #define PRItime PRIuMAX
 395 #define parse_timestamp strtoumax
 396 #define TIME_MAX UINTMAX_MAX
 397 #define TIME_MIN 0
 398
 399 #ifndef PATH_SEP
 400 #define PATH_SEP ':'
 401 #endif
 402
 403 #ifdef HAVE_PATHS_H
 404 #include <paths.h>
 405 #endif
 406 #ifndef _PATH_DEFPATH
 407 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 408 #endif
 409
 410 #ifndef platform_core_config
 411 static inline int noop_core_config(const char *var UNUSED,
 412                                    const char *value UNUSED,
 413                                    void *cb UNUSED)
 414 {
 415         return 0;
 416 }
 417 #define platform_core_config noop_core_config
 418 #endif
 419
 420 int lstat_cache_aware_rmdir(const char *path);
 421 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 422 #define rmdir lstat_cache_aware_rmdir
 423 #endif
 424
 425 #ifndef has_dos_drive_prefix
 426 static inline int git_has_dos_drive_prefix(const char *path)
 427 {
 428         return 0;
 429 }
 430 #define has_dos_drive_prefix git_has_dos_drive_prefix
 431 #endif
 432
 433 #ifndef skip_dos_drive_prefix
 434 static inline int git_skip_dos_drive_prefix(char **path)
 435 {
 436         return 0;
 437 }
 438 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 439 #endif
 440
 441 static inline int git_is_dir_sep(int c)
 442 {
 443         return c == '/';
 444 }
 445 #ifndef is_dir_sep
 446 #define is_dir_sep git_is_dir_sep
 447 #endif
 448
 449 #ifndef offset_1st_component
 450 static inline int git_offset_1st_component(const char *path)
 451 {
 452         return is_dir_sep(path[0]);
 453 }
 454 #define offset_1st_component git_offset_1st_component
 455 #endif
 456
 457 #ifndef is_valid_path
 458 #define is_valid_path(path) 1
 459 #endif
 460
 461 #ifndef is_path_owned_by_current_user
 462
 463 #ifdef __TANDEM
 464 #define ROOT_UID 65535
 465 #else
 466 #define ROOT_UID 0
 467 #endif
 468
 469 /*
 470  * Do not use this function when
 471  * (1) geteuid() did not say we are running as 'root', or
 472  * (2) using this function will compromise the system.
 473  *
 474  * PORTABILITY WARNING:
 475  * This code assumes uid_t is unsigned because that is what sudo does.
 476  * If your uid_t type is signed and all your ids are positive then it
 477  * should all work fine.
 478  * If your version of sudo uses negative values for uid_t or it is
 479  * buggy and return an overflowed value in SUDO_UID, then git might
 480  * fail to grant access to your repository properly or even mistakenly
 481  * grant access to someone else.
 482  * In the unlikely scenario this happened to you, and that is how you
 483  * got to this message, we would like to know about it; so sent us an
 484  * email to git@vger.kernel.org indicating which platform you are
 485  * using and which version of sudo, so we can improve this logic and
 486  * maybe provide you with a patch that would prevent this issue again
 487  * in the future.
 488  */
 489 static inline void extract_id_from_env(const char *env, uid_t *id)
 490 {
 491         const char *real_uid = getenv(env);
 492
 493         /* discard anything empty to avoid a more complex check below */
 494         if (real_uid && *real_uid) {
 495                 char *endptr = NULL;
 496                 unsigned long env_id;
 497
 498                 errno = 0;
 499                 /* silent overflow errors could trigger a bug here */
 500                 env_id = strtoul(real_uid, &endptr, 10);
 501                 if (!*endptr && !errno)
 502                         *id = env_id;
 503         }
 504 }
 505
 506 static inline int is_path_owned_by_current_uid(const char *path,
 507                                                struct strbuf *report UNUSED)
 508 {
 509         struct stat st;
 510         uid_t euid;
 511
 512         if (lstat(path, &st))
 513                 return 0;
 514
 515         euid = geteuid();
 516         if (euid == ROOT_UID)
 517         {
 518                 if (st.st_uid == ROOT_UID)
 519                         return 1;
 520                 else
 521                         extract_id_from_env("SUDO_UID", &euid);
 522         }
 523
 524         return st.st_uid == euid;
 525 }
 526
 527 #define is_path_owned_by_current_user is_path_owned_by_current_uid
 528 #endif
 529
 530 #ifndef find_last_dir_sep
 531 static inline char *git_find_last_dir_sep(const char *path)
 532 {
 533         return strrchr(path, '/');
 534 }
 535 #define find_last_dir_sep git_find_last_dir_sep
 536 #endif
 537
 538 #ifndef has_dir_sep
 539 static inline int git_has_dir_sep(const char *path)
 540 {
 541         return !!strchr(path, '/');
 542 }
 543 #define has_dir_sep(path) git_has_dir_sep(path)
 544 #endif
 545
 546 #ifndef query_user_email
 547 #define query_user_email() NULL
 548 #endif
 549
 550 #ifdef __TANDEM
 551 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 552 #include <floss.h(floss_getpwuid)>
 553 #ifndef NSIG
 554 /*
 555  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 556  * known, by detective work using kill -l as a list is all signals
 557  * instead of signal.h where it should be.
 558  */
 559 # define NSIG 100
 560 #endif
 561 #endif
 562
 563 #if defined(__HP_cc) && (__HP_cc >= 61000)
 564 #define NORETURN __attribute__((noreturn))
 565 #define NORETURN_PTR
 566 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 567 #define NORETURN __attribute__((__noreturn__))
 568 #define NORETURN_PTR __attribute__((__noreturn__))
 569 #elif defined(_MSC_VER)
 570 #define NORETURN __declspec(noreturn)
 571 #define NORETURN_PTR
 572 #else
 573 #define NORETURN
 574 #define NORETURN_PTR
 575 #ifndef __GNUC__
 576 #ifndef __attribute__
 577 #define __attribute__(x)
 578 #endif
 579 #endif
 580 #endif
 581
 582 /* The sentinel attribute is valid from gcc version 4.0 */
 583 #if defined(__GNUC__) && (__GNUC__ >= 4)
 584 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 585 /* warn_unused_result exists as of gcc 3.4.0, but be lazy and check 4.0 */
 586 #define RESULT_MUST_BE_USED __attribute__ ((warn_unused_result))
 587 #else
 588 #define LAST_ARG_MUST_BE_NULL
 589 #define RESULT_MUST_BE_USED
 590 #endif
 591
 592 #define MAYBE_UNUSED __attribute__((__unused__))
 593
 594 #include "compat/bswap.h"
 595
 596 #include "wildmatch.h"
 597
 598 struct strbuf;
 599
 600 /* General helper functions */
 601 NORETURN void usage(const char *err);
 602 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 603 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 604 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 605 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
 606 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 607 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 608 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 609 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 610 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 611
 612 #ifndef NO_OPENSSL
 613 #ifdef APPLE_COMMON_CRYPTO
 614 #include "compat/apple-common-crypto.h"
 615 #else
 616 #include <openssl/evp.h>
 617 #include <openssl/hmac.h>
 618 #endif /* APPLE_COMMON_CRYPTO */
 619 #include <openssl/x509v3.h>
 620 #endif /* NO_OPENSSL */
 621
 622 #ifdef HAVE_OPENSSL_CSPRNG
 623 #include <openssl/rand.h>
 624 #endif
 625
 626 /*
 627  * Let callers be aware of the constant return value; this can help
 628  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 629  * because other compilers may be confused by this.
 630  */
 631 #if defined(__GNUC__)
 632 static inline int const_error(void)
 633 {
 634         return -1;
 635 }
 636 #define error(...) (error(__VA_ARGS__), const_error())
 637 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 638 #endif
 639
 640 typedef void (*report_fn)(const char *, va_list params);
 641
 642 void set_die_routine(NORETURN_PTR report_fn routine);
 643 report_fn get_die_message_routine(void);
 644 void set_error_routine(report_fn routine);
 645 report_fn get_error_routine(void);
 646 void set_warn_routine(report_fn routine);
 647 report_fn get_warn_routine(void);
 648 void set_die_is_recursing_routine(int (*routine)(void));
 649
 650 int starts_with(const char *str, const char *prefix);
 651 int istarts_with(const char *str, const char *prefix);
 652
 653 /*
 654  * If the string "str" begins with the string found in "prefix", return 1.
 655  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 656  * the string right after the prefix).
 657  *
 658  * Otherwise, return 0 and leave "out" untouched.
 659  *
 660  * Examples:
 661  *
 662  *   [extract branch name, fail if not a branch]
 663  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 664  *      return -1;
 665  *
 666  *   [skip prefix if present, otherwise use whole string]
 667  *   skip_prefix(name, "refs/heads/", &name);
 668  */
 669 static inline int skip_prefix(const char *str, const char *prefix,
 670                               const char **out)
 671 {
 672         do {
 673                 if (!*prefix) {
 674                         *out = str;
 675                         return 1;
 676                 }
 677         } while (*str++ == *prefix++);
 678         return 0;
 679 }
 680
 681 /*
 682  * If the string "str" is the same as the string in "prefix", then the "arg"
 683  * parameter is set to the "def" parameter and 1 is returned.
 684  * If the string "str" begins with the string found in "prefix" and then a
 685  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 686  * (i.e., to the point in the string right after the prefix and the "=" sign),
 687  * and 1 is returned.
 688  *
 689  * Otherwise, return 0 and leave "arg" untouched.
 690  *
 691  * When we accept both a "--key" and a "--key=<val>" option, this function
 692  * can be used instead of !strcmp(arg, "--key") and then
 693  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 694  */
 695 int skip_to_optional_arg_default(const char *str, const char *prefix,
 696                                  const char **arg, const char *def);
 697
 698 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 699                                        const char **arg)
 700 {
 701         return skip_to_optional_arg_default(str, prefix, arg, "");
 702 }
 703
 704 /*
 705  * Like skip_prefix, but promises never to read past "len" bytes of the input
 706  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 707  */
 708 static inline int skip_prefix_mem(const char *buf, size_t len,
 709                                   const char *prefix,
 710                                   const char **out, size_t *outlen)
 711 {
 712         size_t prefix_len = strlen(prefix);
 713         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 714                 *out = buf + prefix_len;
 715                 *outlen = len - prefix_len;
 716                 return 1;
 717         }
 718         return 0;
 719 }
 720
 721 /*
 722  * If buf ends with suffix, return 1 and subtract the length of the suffix
 723  * from *len. Otherwise, return 0 and leave *len untouched.
 724  */
 725 static inline int strip_suffix_mem(const char *buf, size_t *len,
 726                                    const char *suffix)
 727 {
 728         size_t suflen = strlen(suffix);
 729         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 730                 return 0;
 731         *len -= suflen;
 732         return 1;
 733 }
 734
 735 /*
 736  * If str ends with suffix, return 1 and set *len to the size of the string
 737  * without the suffix. Otherwise, return 0 and set *len to the size of the
 738  * string.
 739  *
 740  * Note that we do _not_ NUL-terminate str to the new length.
 741  */
 742 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 743 {
 744         *len = strlen(str);
 745         return strip_suffix_mem(str, len, suffix);
 746 }
 747
 748 static inline int ends_with(const char *str, const char *suffix)
 749 {
 750         size_t len;
 751         return strip_suffix(str, suffix, &len);
 752 }
 753
 754 #define SWAP(a, b) do {                                         \
 755         void *_swap_a_ptr = &(a);                               \
 756         void *_swap_b_ptr = &(b);                               \
 757         unsigned char _swap_buffer[sizeof(a)];                  \
 758         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 759         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 760                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 761         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 762 } while (0)
 763
 764 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 765
 766 #ifndef PROT_READ
 767 #define PROT_READ 1
 768 #define PROT_WRITE 2
 769 #define MAP_PRIVATE 1
 770 #endif
 771
 772 #define mmap git_mmap
 773 #define munmap git_munmap
 774 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 775 int git_munmap(void *start, size_t length);
 776
 777 #else /* NO_MMAP || USE_WIN32_MMAP */
 778
 779 #include <sys/mman.h>
 780
 781 #endif /* NO_MMAP || USE_WIN32_MMAP */
 782
 783 #ifdef NO_MMAP
 784
 785 /* This value must be multiple of (pagesize * 2) */
 786 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 787
 788 #else /* NO_MMAP */
 789
 790 /* This value must be multiple of (pagesize * 2) */
 791 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 792         (sizeof(void*) >= 8 \
 793                 ?  1 * 1024 * 1024 * 1024 \
 794                 : 32 * 1024 * 1024)
 795
 796 #endif /* NO_MMAP */
 797
 798 #ifndef MAP_FAILED
 799 #define MAP_FAILED ((void *)-1)
 800 #endif
 801
 802 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 803 #define on_disk_bytes(st) ((st).st_size)
 804 #else
 805 #define on_disk_bytes(st) ((st).st_blocks * 512)
 806 #endif
 807
 808 #ifdef NEEDS_MODE_TRANSLATION
 809 #undef S_IFMT
 810 #undef S_IFREG
 811 #undef S_IFDIR
 812 #undef S_IFLNK
 813 #undef S_IFBLK
 814 #undef S_IFCHR
 815 #undef S_IFIFO
 816 #undef S_IFSOCK
 817 #define S_IFMT   0170000
 818 #define S_IFREG  0100000
 819 #define S_IFDIR  0040000
 820 #define S_IFLNK  0120000
 821 #define S_IFBLK  0060000
 822 #define S_IFCHR  0020000
 823 #define S_IFIFO  0010000
 824 #define S_IFSOCK 0140000
 825 #ifdef stat
 826 #undef stat
 827 #endif
 828 #define stat(path, buf) git_stat(path, buf)
 829 int git_stat(const char *, struct stat *);
 830 #ifdef fstat
 831 #undef fstat
 832 #endif
 833 #define fstat(fd, buf) git_fstat(fd, buf)
 834 int git_fstat(int, struct stat *);
 835 #ifdef lstat
 836 #undef lstat
 837 #endif
 838 #define lstat(path, buf) git_lstat(path, buf)
 839 int git_lstat(const char *, struct stat *);
 840 #endif
 841
 842 #define DEFAULT_PACKED_GIT_LIMIT \
 843         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 844
 845 #ifdef NO_PREAD
 846 #define pread git_pread
 847 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 848 #endif
 849 /*
 850  * Forward decl that will remind us if its twin in cache.h changes.
 851  * This function is used in compat/pread.c.  But we can't include
 852  * cache.h there.
 853  */
 854 ssize_t read_in_full(int fd, void *buf, size_t count);
 855
 856 #ifdef NO_SETENV
 857 #define setenv gitsetenv
 858 int gitsetenv(const char *, const char *, int);
 859 #endif
 860
 861 #ifdef NO_MKDTEMP
 862 #define mkdtemp gitmkdtemp
 863 char *gitmkdtemp(char *);
 864 #endif
 865
 866 #ifdef NO_UNSETENV
 867 #define unsetenv gitunsetenv
 868 int gitunsetenv(const char *);
 869 #endif
 870
 871 #ifdef NO_STRCASESTR
 872 #define strcasestr gitstrcasestr
 873 char *gitstrcasestr(const char *haystack, const char *needle);
 874 #endif
 875
 876 #ifdef NO_STRLCPY
 877 #define strlcpy gitstrlcpy
 878 size_t gitstrlcpy(char *, const char *, size_t);
 879 #endif
 880
 881 #ifdef NO_STRTOUMAX
 882 #define strtoumax gitstrtoumax
 883 uintmax_t gitstrtoumax(const char *, char **, int);
 884 #define strtoimax gitstrtoimax
 885 intmax_t gitstrtoimax(const char *, char **, int);
 886 #endif
 887
 888 #ifdef NO_HSTRERROR
 889 #define hstrerror githstrerror
 890 const char *githstrerror(int herror);
 891 #endif
 892
 893 #ifdef NO_MEMMEM
 894 #define memmem gitmemmem
 895 void *gitmemmem(const void *haystack, size_t haystacklen,
 896                 const void *needle, size_t needlelen);
 897 #endif
 898
 899 #ifdef OVERRIDE_STRDUP
 900 #ifdef strdup
 901 #undef strdup
 902 #endif
 903 #define strdup gitstrdup
 904 char *gitstrdup(const char *s);
 905 #endif
 906
 907 #ifdef NO_GETPAGESIZE
 908 #define getpagesize() sysconf(_SC_PAGESIZE)
 909 #endif
 910
 911 #ifndef O_CLOEXEC
 912 #define O_CLOEXEC 0
 913 #endif
 914
 915 #ifdef FREAD_READS_DIRECTORIES
 916 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 917 #  ifdef fopen
 918 #   undef fopen
 919 #  endif
 920 #  define fopen(a,b) git_fopen(a,b)
 921 # endif
 922 FILE *git_fopen(const char*, const char*);
 923 #endif
 924
 925 #ifdef SNPRINTF_RETURNS_BOGUS
 926 #ifdef snprintf
 927 #undef snprintf
 928 #endif
 929 #define snprintf git_snprintf
 930 int git_snprintf(char *str, size_t maxsize,
 931                  const char *format, ...);
 932 #ifdef vsnprintf
 933 #undef vsnprintf
 934 #endif
 935 #define vsnprintf git_vsnprintf
 936 int git_vsnprintf(char *str, size_t maxsize,
 937                   const char *format, va_list ap);
 938 #endif
 939
 940 #ifdef OPEN_RETURNS_EINTR
 941 #undef open
 942 #define open git_open_with_retry
 943 int git_open_with_retry(const char *path, int flag, ...);
 944 #endif
 945
 946 #ifdef __GLIBC_PREREQ
 947 #if __GLIBC_PREREQ(2, 1)
 948 #define HAVE_STRCHRNUL
 949 #endif
 950 #endif
 951
 952 #ifndef HAVE_STRCHRNUL
 953 #define strchrnul gitstrchrnul
 954 static inline char *gitstrchrnul(const char *s, int c)
 955 {
 956         while (*s && *s != c)
 957                 s++;
 958         return (char *)s;
 959 }
 960 #endif
 961
 962 #ifdef NO_INET_PTON
 963 int inet_pton(int af, const char *src, void *dst);
 964 #endif
 965
 966 #ifdef NO_INET_NTOP
 967 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 968 #endif
 969
 970 #ifdef NO_PTHREADS
 971 #define atexit git_atexit
 972 int git_atexit(void (*handler)(void));
 973 #endif
 974
 975 static inline size_t st_add(size_t a, size_t b)
 976 {
 977         if (unsigned_add_overflows(a, b))
 978                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 979                     (uintmax_t)a, (uintmax_t)b);
 980         return a + b;
 981 }
 982 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 983 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 984
 985 static inline size_t st_mult(size_t a, size_t b)
 986 {
 987         if (unsigned_mult_overflows(a, b))
 988                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 989                     (uintmax_t)a, (uintmax_t)b);
 990         return a * b;
 991 }
 992
 993 static inline size_t st_sub(size_t a, size_t b)
 994 {
 995         if (a < b)
 996                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 997                     (uintmax_t)a, (uintmax_t)b);
 998         return a - b;
 999 }
1000
1001 static inline size_t st_left_shift(size_t a, unsigned shift)
1002 {
1003         if (unsigned_left_shift_overflows(a, shift))
1004                 die("size_t overflow: %"PRIuMAX" << %u",
1005                     (uintmax_t)a, shift);
1006         return a << shift;
1007 }
1008
1009 static inline unsigned long cast_size_t_to_ulong(size_t a)
1010 {
1011         if (a != (unsigned long)a)
1012                 die("object too large to read on this platform: %"
1013                     PRIuMAX" is cut off to %lu",
1014                     (uintmax_t)a, (unsigned long)a);
1015         return (unsigned long)a;
1016 }
1017
1018 /*
1019  * Limit size of IO chunks, because huge chunks only cause pain.  OS X
1020  * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
1021  * the absence of bugs, large chunks can result in bad latencies when
1022  * you decide to kill the process.
1023  *
1024  * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
1025  * that is smaller than that, clip it to SSIZE_MAX, as a call to
1026  * read(2) or write(2) larger than that is allowed to fail.  As the last
1027  * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
1028  * to override this, if the definition of SSIZE_MAX given by the platform
1029  * is broken.
1030  */
1031 #ifndef MAX_IO_SIZE
1032 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
1033 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
1034 #  define MAX_IO_SIZE SSIZE_MAX
1035 # else
1036 #  define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
1037 # endif
1038 #endif
1039
1040 #ifdef HAVE_ALLOCA_H
1041 # include <alloca.h>
1042 # define xalloca(size)      (alloca(size))
1043 # define xalloca_free(p)    do {} while (0)
1044 #else
1045 # define xalloca(size)      (xmalloc(size))
1046 # define xalloca_free(p)    (free(p))
1047 #endif
1048 char *xstrdup(const char *str);
1049 void *xmalloc(size_t size);
1050 void *xmallocz(size_t size);
1051 void *xmallocz_gently(size_t size);
1052 void *xmemdupz(const void *data, size_t len);
1053 char *xstrndup(const char *str, size_t len);
1054 void *xrealloc(void *ptr, size_t size);
1055 void *xcalloc(size_t nmemb, size_t size);
1056 void xsetenv(const char *name, const char *value, int overwrite);
1057 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1058 const char *mmap_os_err(void);
1059 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1060 int xopen(const char *path, int flags, ...);
1061 ssize_t xread(int fd, void *buf, size_t len);
1062 ssize_t xwrite(int fd, const void *buf, size_t len);
1063 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
1064 int xdup(int fd);
1065 FILE *xfopen(const char *path, const char *mode);
1066 FILE *xfdopen(int fd, const char *mode);
1067 int xmkstemp(char *temp_filename);
1068 int xmkstemp_mode(char *temp_filename, int mode);
1069 char *xgetcwd(void);
1070 FILE *fopen_for_writing(const char *path);
1071 FILE *fopen_or_warn(const char *path, const char *mode);
1072
1073 /*
1074  * Like strncmp, but only return zero if s is NUL-terminated and exactly len
1075  * characters long.  If it is not, consider it greater than t.
1076  */
1077 int xstrncmpz(const char *s, const char *t, size_t len);
1078
1079 /*
1080  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
1081  * that ptr is used twice, so don't pass e.g. ptr++.
1082  */
1083 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
1084
1085 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
1086 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
1087 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
1088
1089 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
1090         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1091 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
1092 {
1093         if (n)
1094                 memcpy(dst, src, st_mult(size, n));
1095 }
1096
1097 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
1098         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1099 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
1100 {
1101         if (n)
1102                 memmove(dst, src, st_mult(size, n));
1103 }
1104
1105 /*
1106  * These functions help you allocate structs with flex arrays, and copy
1107  * the data directly into the array. For example, if you had:
1108  *
1109  *   struct foo {
1110  *     int bar;
1111  *     char name[FLEX_ARRAY];
1112  *   };
1113  *
1114  * you can do:
1115  *
1116  *   struct foo *f;
1117  *   FLEX_ALLOC_MEM(f, name, src, len);
1118  *
1119  * to allocate a "foo" with the contents of "src" in the "name" field.
1120  * The resulting struct is automatically zero'd, and the flex-array field
1121  * is NUL-terminated (whether the incoming src buffer was or not).
1122  *
1123  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1124  * but do want to store a pointer to some extra data in the same allocated
1125  * block. For example, if you have:
1126  *
1127  *   struct foo {
1128  *     char *name;
1129  *     int bar;
1130  *   };
1131  *
1132  * you can do:
1133  *
1134  *   struct foo *f;
1135  *   FLEXPTR_ALLOC_STR(f, name, src);
1136  *
1137  * and "name" will point to a block of memory after the struct, which will be
1138  * freed along with the struct (but the pointer can be repointed anywhere).
1139  *
1140  * The *_STR variants accept a string parameter rather than a ptr/len
1141  * combination.
1142  *
1143  * Note that these macros will evaluate the first parameter multiple
1144  * times, and it must be assignable as an lvalue.
1145  */
1146 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1147         size_t flex_array_len_ = (len); \
1148         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1149         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1150 } while (0)
1151 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1152         size_t flex_array_len_ = (len); \
1153         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1154         memcpy((x) + 1, (buf), flex_array_len_); \
1155         (x)->ptrname = (void *)((x)+1); \
1156 } while(0)
1157 #define FLEX_ALLOC_STR(x, flexname, str) \
1158         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1159 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1160         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1161
1162 static inline char *xstrdup_or_null(const char *str)
1163 {
1164         return str ? xstrdup(str) : NULL;
1165 }
1166
1167 static inline size_t xsize_t(off_t len)
1168 {
1169         if (len < 0 || (uintmax_t) len > SIZE_MAX)
1170                 die("Cannot handle files this big");
1171         return (size_t) len;
1172 }
1173
1174 __attribute__((format (printf, 3, 4)))
1175 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1176
1177 #ifndef HOST_NAME_MAX
1178 #define HOST_NAME_MAX 256
1179 #endif
1180
1181 int xgethostname(char *buf, size_t len);
1182
1183 /* in ctype.c, for kwset users */
1184 extern const unsigned char tolower_trans_tbl[256];
1185
1186 /* Sane ctype - no locale, and works with signed chars */
1187 #undef isascii
1188 #undef isspace
1189 #undef isdigit
1190 #undef isalpha
1191 #undef isalnum
1192 #undef isprint
1193 #undef islower
1194 #undef isupper
1195 #undef tolower
1196 #undef toupper
1197 #undef iscntrl
1198 #undef ispunct
1199 #undef isxdigit
1200
1201 extern const unsigned char sane_ctype[256];
1202 #define GIT_SPACE 0x01
1203 #define GIT_DIGIT 0x02
1204 #define GIT_ALPHA 0x04
1205 #define GIT_GLOB_SPECIAL 0x08
1206 #define GIT_REGEX_SPECIAL 0x10
1207 #define GIT_PATHSPEC_MAGIC 0x20
1208 #define GIT_CNTRL 0x40
1209 #define GIT_PUNCT 0x80
1210 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1211 #define isascii(x) (((x) & ~0x7f) == 0)
1212 #define isspace(x) sane_istest(x,GIT_SPACE)
1213 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1214 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1215 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1216 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1217 #define islower(x) sane_iscase(x, 1)
1218 #define isupper(x) sane_iscase(x, 0)
1219 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1220 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1221 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1222 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1223                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1224 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1225 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1226 #define toupper(x) sane_case((unsigned char)(x), 0)
1227 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1228
1229 static inline int sane_case(int x, int high)
1230 {
1231         if (sane_istest(x, GIT_ALPHA))
1232                 x = (x & ~0x20) | high;
1233         return x;
1234 }
1235
1236 static inline int sane_iscase(int x, int is_lower)
1237 {
1238         if (!sane_istest(x, GIT_ALPHA))
1239                 return 0;
1240
1241         if (is_lower)
1242                 return (x & 0x20) != 0;
1243         else
1244                 return (x & 0x20) == 0;
1245 }
1246
1247 /*
1248  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1249  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1250  * locale-specific conversions).
1251  */
1252 static inline int skip_iprefix(const char *str, const char *prefix,
1253                                const char **out)
1254 {
1255         do {
1256                 if (!*prefix) {
1257                         *out = str;
1258                         return 1;
1259                 }
1260         } while (tolower(*str++) == tolower(*prefix++));
1261         return 0;
1262 }
1263
1264 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1265 {
1266         unsigned long ul;
1267         char *p;
1268
1269         errno = 0;
1270         /* negative values would be accepted by strtoul */
1271         if (strchr(s, '-'))
1272                 return -1;
1273         ul = strtoul(s, &p, base);
1274         if (errno || *p || p == s || (unsigned int) ul != ul)
1275                 return -1;
1276         *result = ul;
1277         return 0;
1278 }
1279
1280 static inline int strtol_i(char const *s, int base, int *result)
1281 {
1282         long ul;
1283         char *p;
1284
1285         errno = 0;
1286         ul = strtol(s, &p, base);
1287         if (errno || *p || p == s || (int) ul != ul)
1288                 return -1;
1289         *result = ul;
1290         return 0;
1291 }
1292
1293 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1294                       int(*compar)(const void *, const void *));
1295 #ifdef INTERNAL_QSORT
1296 #define qsort git_stable_qsort
1297 #endif
1298
1299 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1300 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1301                               int(*compar)(const void *, const void *))
1302 {
1303         if (nmemb > 1)
1304                 qsort(base, nmemb, size, compar);
1305 }
1306
1307 #define STABLE_QSORT(base, n, compar) \
1308         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1309
1310 #ifndef HAVE_ISO_QSORT_S
1311 int git_qsort_s(void *base, size_t nmemb, size_t size,
1312                 int (*compar)(const void *, const void *, void *), void *ctx);
1313 #define qsort_s git_qsort_s
1314 #endif
1315
1316 #define QSORT_S(base, n, compar, ctx) do {                      \
1317         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1318                 BUG("qsort_s() failed");                        \
1319 } while (0)
1320
1321 #ifndef REG_STARTEND
1322 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1323 #endif
1324
1325 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1326                               size_t nmatch, regmatch_t pmatch[], int eflags)
1327 {
1328         assert(nmatch > 0 && pmatch);
1329         pmatch[0].rm_so = 0;
1330         pmatch[0].rm_eo = size;
1331         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1332 }
1333
1334 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1335 # define FORCE_DIR_SET_GID S_ISGID
1336 #else
1337 # define FORCE_DIR_SET_GID 0
1338 #endif
1339
1340 #ifdef NO_NSEC
1341 #undef USE_NSEC
1342 #define ST_CTIME_NSEC(st) 0
1343 #define ST_MTIME_NSEC(st) 0
1344 #else
1345 #ifdef USE_ST_TIMESPEC
1346 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1347 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1348 #else
1349 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1350 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1351 #endif
1352 #endif
1353
1354 #ifdef UNRELIABLE_FSTAT
1355 #define fstat_is_reliable() 0
1356 #else
1357 #define fstat_is_reliable() 1
1358 #endif
1359
1360 #ifndef va_copy
1361 /*
1362  * Since an obvious implementation of va_list would be to make it a
1363  * pointer into the stack frame, a simple assignment will work on
1364  * many systems.  But let's try to be more portable.
1365  */
1366 #ifdef __va_copy
1367 #define va_copy(dst, src) __va_copy(dst, src)
1368 #else
1369 #define va_copy(dst, src) ((dst) = (src))
1370 #endif
1371 #endif
1372
1373 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1374 extern int BUG_exit_code;
1375
1376 /* usage.c: if bug() is called we should have a BUG_if_bug() afterwards */
1377 extern int bug_called_must_BUG;
1378
1379 __attribute__((format (printf, 3, 4))) NORETURN
1380 void BUG_fl(const char *file, int line, const char *fmt, ...);
1381 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1382 __attribute__((format (printf, 3, 4)))
1383 void bug_fl(const char *file, int line, const char *fmt, ...);
1384 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)
1385 #define BUG_if_bug(...) do { \
1386         if (bug_called_must_BUG) \
1387                 BUG_fl(__FILE__, __LINE__, __VA_ARGS__); \
1388 } while (0)
1389
1390 #ifndef FSYNC_METHOD_DEFAULT
1391 #ifdef __APPLE__
1392 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_WRITEOUT_ONLY
1393 #else
1394 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_FSYNC
1395 #endif
1396 #endif
1397
1398 enum fsync_action {
1399         FSYNC_WRITEOUT_ONLY,
1400         FSYNC_HARDWARE_FLUSH
1401 };
1402
1403 /*
1404  * Issues an fsync against the specified file according to the specified mode.
1405  *
1406  * FSYNC_WRITEOUT_ONLY attempts to use interfaces available on some operating
1407  * systems to flush the OS cache without issuing a flush command to the storage
1408  * controller. If those interfaces are unavailable, the function fails with
1409  * ENOSYS.
1410  *
1411  * FSYNC_HARDWARE_FLUSH does an OS writeout and hardware flush to ensure that
1412  * changes are durable. It is not expected to fail.
1413  */
1414 int git_fsync(int fd, enum fsync_action action);
1415
1416 /*
1417  * Writes out trace statistics for fsync using the trace2 API.
1418  */
1419 void trace_git_fsync_stats(void);
1420
1421 /*
1422  * Preserves errno, prints a message, but gives no warning for ENOENT.
1423  * Returns 0 on success, which includes trying to unlink an object that does
1424  * not exist.
1425  */
1426 int unlink_or_warn(const char *path);
1427  /*
1428   * Tries to unlink file.  Returns 0 if unlink succeeded
1429   * or the file already didn't exist.  Returns -1 and
1430   * appends a message to err suitable for
1431   * 'error("%s", err->buf)' on error.
1432   */
1433 int unlink_or_msg(const char *file, struct strbuf *err);
1434 /*
1435  * Preserves errno, prints a message, but gives no warning for ENOENT.
1436  * Returns 0 on success, which includes trying to remove a directory that does
1437  * not exist.
1438  */
1439 int rmdir_or_warn(const char *path);
1440 /*
1441  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1442  * the supplied file mode.
1443  */
1444 int remove_or_warn(unsigned int mode, const char *path);
1445
1446 /*
1447  * Call access(2), but warn for any error except "missing file"
1448  * (ENOENT or ENOTDIR).
1449  */
1450 #define ACCESS_EACCES_OK (1U << 0)
1451 int access_or_warn(const char *path, int mode, unsigned flag);
1452 int access_or_die(const char *path, int mode, unsigned flag);
1453
1454 /* Warn on an inaccessible file if errno indicates this is an error */
1455 int warn_on_fopen_errors(const char *path);
1456
1457 /*
1458  * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1459  * may be racy. Do not use this as protection against an attacker who can
1460  * simultaneously create paths.
1461  */
1462 int open_nofollow(const char *path, int flags);
1463
1464 #ifndef SHELL_PATH
1465 # define SHELL_PATH "/bin/sh"
1466 #endif
1467
1468 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1469 static inline void flockfile(FILE *fh)
1470 {
1471         ; /* nothing */
1472 }
1473 static inline void funlockfile(FILE *fh)
1474 {
1475         ; /* nothing */
1476 }
1477 #define getc_unlocked(fh) getc(fh)
1478 #endif
1479
1480 #ifdef FILENO_IS_A_MACRO
1481 int git_fileno(FILE *stream);
1482 # ifndef COMPAT_CODE_FILENO
1483 #  undef fileno
1484 #  define fileno(p) git_fileno(p)
1485 # endif
1486 #endif
1487
1488 #ifdef NEED_ACCESS_ROOT_HANDLER
1489 int git_access(const char *path, int mode);
1490 # ifndef COMPAT_CODE_ACCESS
1491 #  ifdef access
1492 #  undef access
1493 #  endif
1494 #  define access(path, mode) git_access(path, mode)
1495 # endif
1496 #endif
1497
1498 /*
1499  * Our code often opens a path to an optional file, to work on its
1500  * contents when we can successfully open it.  We can ignore a failure
1501  * to open if such an optional file does not exist, but we do want to
1502  * report a failure in opening for other reasons (e.g. we got an I/O
1503  * error, or the file is there, but we lack the permission to open).
1504  *
1505  * Call this function after seeing an error from open() or fopen() to
1506  * see if the errno indicates a missing file that we can safely ignore.
1507  */
1508 static inline int is_missing_file_error(int errno_)
1509 {
1510         return (errno_ == ENOENT || errno_ == ENOTDIR);
1511 }
1512
1513 int cmd_main(int, const char **);
1514
1515 /*
1516  * Intercept all calls to exit() and route them to trace2 to
1517  * optionally emit a message before calling the real exit().
1518  */
1519 int common_exit(const char *file, int line, int code);
1520 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
1521
1522 /*
1523  * You can mark a stack variable with UNLEAK(var) to avoid it being
1524  * reported as a leak by tools like LSAN or valgrind. The argument
1525  * should generally be the variable itself (not its address and not what
1526  * it points to). It's safe to use this on pointers which may already
1527  * have been freed, or on pointers which may still be in use.
1528  *
1529  * Use this _only_ for a variable that leaks by going out of scope at
1530  * program exit (so only from cmd_* functions or their direct helpers).
1531  * Normal functions, especially those which may be called multiple
1532  * times, should actually free their memory. This is only meant as
1533  * an annotation, and does nothing in non-leak-checking builds.
1534  */
1535 #ifdef SUPPRESS_ANNOTATED_LEAKS
1536 void unleak_memory(const void *ptr, size_t len);
1537 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1538 #else
1539 #define UNLEAK(var) do {} while (0)
1540 #endif
1541
1542 #define z_const
1543 #include <zlib.h>
1544
1545 #if ZLIB_VERNUM < 0x1290
1546 /*
1547  * This is uncompress2, which is only available in zlib >= 1.2.9
1548  * (released as of early 2017). See compat/zlib-uncompress2.c.
1549  */
1550 int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
1551                 uLong *sourceLen);
1552 #endif
1553
1554 /*
1555  * This include must come after system headers, since it introduces macros that
1556  * replace system names.
1557  */
1558 #include "banned.h"
1559
1560 /*
1561  * container_of - Get the address of an object containing a field.
1562  *
1563  * @ptr: pointer to the field.
1564  * @type: type of the object.
1565  * @member: name of the field within the object.
1566  */
1567 #define container_of(ptr, type, member) \
1568         ((type *) ((char *)(ptr) - offsetof(type, member)))
1569
1570 /*
1571  * helper function for `container_of_or_null' to avoid multiple
1572  * evaluation of @ptr
1573  */
1574 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1575 {
1576         return ptr ? (char *)ptr - offset : NULL;
1577 }
1578
1579 /*
1580  * like `container_of', but allows returned value to be NULL
1581  */
1582 #define container_of_or_null(ptr, type, member) \
1583         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1584
1585 /*
1586  * like offsetof(), but takes a pointer to a variable of type which
1587  * contains @member, instead of a specified type.
1588  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1589  * everywhere.
1590  */
1591 #if defined(__GNUC__) /* clang sets this, too */
1592 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1593 #else /* !__GNUC__ */
1594 #define OFFSETOF_VAR(ptr, member) \
1595         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1596 #endif /* !__GNUC__ */
1597
1598 void sleep_millisec(int millisec);
1599
1600 /*
1601  * Generate len bytes from the system cryptographically secure PRNG.
1602  * Returns 0 on success and -1 on error, setting errno.  The inability to
1603  * satisfy the full request is an error.
1604  */
1605 int csprng_bytes(void *buf, size_t len);
1606
1607 #endif