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 #include <locale.h>
 229 #ifdef NEEDS_SYS_PARAM_H
 230 #include <sys/param.h>
 231 #endif
 232 #include <sys/types.h>
 233 #include <dirent.h>
 234 #include <sys/time.h>
 235 #include <time.h>
 236 #include <signal.h>
 237 #include <assert.h>
 238 #include <regex.h>
 239 #include <utime.h>
 240 #include <syslog.h>
 241 #if !defined(NO_POLL_H)
 242 #include <poll.h>
 243 #elif !defined(NO_SYS_POLL_H)
 244 #include <sys/poll.h>
 245 #else
 246 /* Pull the compat stuff */
 247 #include <poll.h>
 248 #endif
 249 #ifdef HAVE_BSD_SYSCTL
 250 #include <sys/sysctl.h>
 251 #endif
 252
 253 /* Used by compat/win32/path-utils.h, and more */
 254 static inline int is_xplatform_dir_sep(int c)
 255 {
 256         return c == '/' || c == '\\';
 257 }
 258
 259 #if defined(__CYGWIN__)
 260 #include "compat/win32/path-utils.h"
 261 #endif
 262 #if defined(__MINGW32__)
 263 /* pull in Windows compatibility stuff */
 264 #include "compat/win32/path-utils.h"
 265 #include "compat/mingw.h"
 266 #elif defined(_MSC_VER)
 267 #include "compat/win32/path-utils.h"
 268 #include "compat/msvc.h"
 269 #else
 270 #include <sys/utsname.h>
 271 #include <sys/wait.h>
 272 #include <sys/resource.h>
 273 #include <sys/socket.h>
 274 #include <sys/ioctl.h>
 275 #include <sys/statvfs.h>
 276 #include <termios.h>
 277 #ifndef NO_SYS_SELECT_H
 278 #include <sys/select.h>
 279 #endif
 280 #include <netinet/in.h>
 281 #include <netinet/tcp.h>
 282 #include <arpa/inet.h>
 283 #include <netdb.h>
 284 #include <pwd.h>
 285 #include <sys/un.h>
 286 #ifndef NO_INTTYPES_H
 287 #include <inttypes.h>
 288 #else
 289 #include <stdint.h>
 290 #endif
 291 #ifdef HAVE_ARC4RANDOM_LIBBSD
 292 #include <bsd/stdlib.h>
 293 #endif
 294 #ifdef HAVE_GETRANDOM
 295 #include <sys/random.h>
 296 #endif
 297 #ifdef NO_INTPTR_T
 298 /*
 299  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 300  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 301  * while on IP16 and IP16L32 it is "int" (resp. "short")
 302  * Size needs to match (or exceed) 'sizeof(void *)'.
 303  * We can't take "long long" here as not everybody has it.
 304  */
 305 typedef long intptr_t;
 306 typedef unsigned long uintptr_t;
 307 #endif
 308 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 309 #include <grp.h>
 310 #define _ALL_SOURCE 1
 311 #endif
 312
 313 /* used on Mac OS X */
 314 #ifdef PRECOMPOSE_UNICODE
 315 #include "compat/precompose_utf8.h"
 316 #else
 317 static inline const char *precompose_argv_prefix(int argc, const char **argv, const char *prefix)
 318 {
 319         return prefix;
 320 }
 321 static inline const char *precompose_string_if_needed(const char *in)
 322 {
 323         return in;
 324 }
 325
 326 #define probe_utf8_pathname_composition()
 327 #endif
 328
 329 #ifdef MKDIR_WO_TRAILING_SLASH
 330 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 331 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 332 #endif
 333
 334 #ifdef NO_STRUCT_ITIMERVAL
 335 struct itimerval {
 336         struct timeval it_interval;
 337         struct timeval it_value;
 338 };
 339 #endif
 340
 341 #ifdef NO_SETITIMER
 342 static inline int setitimer(int which, const struct itimerval *value, struct itimerval *newvalue) {
 343         return 0; /* pretend success */
 344 }
 345 #endif
 346
 347 #ifndef NO_LIBGEN_H
 348 #include <libgen.h>
 349 #else
 350 #define basename gitbasename
 351 char *gitbasename(char *);
 352 #define dirname gitdirname
 353 char *gitdirname(char *);
 354 #endif
 355
 356 #ifndef NO_ICONV
 357 #include <iconv.h>
 358 #endif
 359
 360 #ifndef NO_OPENSSL
 361 #ifdef __APPLE__
 362 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 363 #include <AvailabilityMacros.h>
 364 #undef DEPRECATED_ATTRIBUTE
 365 #define DEPRECATED_ATTRIBUTE
 366 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 367 #endif
 368 #include <openssl/ssl.h>
 369 #include <openssl/err.h>
 370 #endif
 371
 372 #ifdef HAVE_SYSINFO
 373 # include <sys/sysinfo.h>
 374 #endif
 375
 376 /* On most systems <netdb.h> would have given us this, but
 377  * not on some systems (e.g. z/OS).
 378  */
 379 #ifndef NI_MAXHOST
 380 #define NI_MAXHOST 1025
 381 #endif
 382
 383 #ifndef NI_MAXSERV
 384 #define NI_MAXSERV 32
 385 #endif
 386
 387 /* On most systems <limits.h> would have given us this, but
 388  * not on some systems (e.g. GNU/Hurd).
 389  */
 390 #ifndef PATH_MAX
 391 #define PATH_MAX 4096
 392 #endif
 393
 394 typedef uintmax_t timestamp_t;
 395 #define PRItime PRIuMAX
 396 #define parse_timestamp strtoumax
 397 #define TIME_MAX UINTMAX_MAX
 398 #define TIME_MIN 0
 399
 400 #ifndef PATH_SEP
 401 #define PATH_SEP ':'
 402 #endif
 403
 404 #ifdef HAVE_PATHS_H
 405 #include <paths.h>
 406 #endif
 407 #ifndef _PATH_DEFPATH
 408 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 409 #endif
 410
 411 #ifndef platform_core_config
 412 static inline int noop_core_config(const char *var UNUSED,
 413                                    const char *value UNUSED,
 414                                    void *cb UNUSED)
 415 {
 416         return 0;
 417 }
 418 #define platform_core_config noop_core_config
 419 #endif
 420
 421 int lstat_cache_aware_rmdir(const char *path);
 422 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 423 #define rmdir lstat_cache_aware_rmdir
 424 #endif
 425
 426 #ifndef has_dos_drive_prefix
 427 static inline int git_has_dos_drive_prefix(const char *path)
 428 {
 429         return 0;
 430 }
 431 #define has_dos_drive_prefix git_has_dos_drive_prefix
 432 #endif
 433
 434 #ifndef skip_dos_drive_prefix
 435 static inline int git_skip_dos_drive_prefix(char **path)
 436 {
 437         return 0;
 438 }
 439 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 440 #endif
 441
 442 static inline int git_is_dir_sep(int c)
 443 {
 444         return c == '/';
 445 }
 446 #ifndef is_dir_sep
 447 #define is_dir_sep git_is_dir_sep
 448 #endif
 449
 450 #ifndef offset_1st_component
 451 static inline int git_offset_1st_component(const char *path)
 452 {
 453         return is_dir_sep(path[0]);
 454 }
 455 #define offset_1st_component git_offset_1st_component
 456 #endif
 457
 458 #ifndef is_valid_path
 459 #define is_valid_path(path) 1
 460 #endif
 461
 462 #ifndef is_path_owned_by_current_user
 463
 464 #ifdef __TANDEM
 465 #define ROOT_UID 65535
 466 #else
 467 #define ROOT_UID 0
 468 #endif
 469
 470 /*
 471  * Do not use this function when
 472  * (1) geteuid() did not say we are running as 'root', or
 473  * (2) using this function will compromise the system.
 474  *
 475  * PORTABILITY WARNING:
 476  * This code assumes uid_t is unsigned because that is what sudo does.
 477  * If your uid_t type is signed and all your ids are positive then it
 478  * should all work fine.
 479  * If your version of sudo uses negative values for uid_t or it is
 480  * buggy and return an overflowed value in SUDO_UID, then git might
 481  * fail to grant access to your repository properly or even mistakenly
 482  * grant access to someone else.
 483  * In the unlikely scenario this happened to you, and that is how you
 484  * got to this message, we would like to know about it; so sent us an
 485  * email to git@vger.kernel.org indicating which platform you are
 486  * using and which version of sudo, so we can improve this logic and
 487  * maybe provide you with a patch that would prevent this issue again
 488  * in the future.
 489  */
 490 static inline void extract_id_from_env(const char *env, uid_t *id)
 491 {
 492         const char *real_uid = getenv(env);
 493
 494         /* discard anything empty to avoid a more complex check below */
 495         if (real_uid && *real_uid) {
 496                 char *endptr = NULL;
 497                 unsigned long env_id;
 498
 499                 errno = 0;
 500                 /* silent overflow errors could trigger a bug here */
 501                 env_id = strtoul(real_uid, &endptr, 10);
 502                 if (!*endptr && !errno)
 503                         *id = env_id;
 504         }
 505 }
 506
 507 static inline int is_path_owned_by_current_uid(const char *path,
 508                                                struct strbuf *report UNUSED)
 509 {
 510         struct stat st;
 511         uid_t euid;
 512
 513         if (lstat(path, &st))
 514                 return 0;
 515
 516         euid = geteuid();
 517         if (euid == ROOT_UID)
 518         {
 519                 if (st.st_uid == ROOT_UID)
 520                         return 1;
 521                 else
 522                         extract_id_from_env("SUDO_UID", &euid);
 523         }
 524
 525         return st.st_uid == euid;
 526 }
 527
 528 #define is_path_owned_by_current_user is_path_owned_by_current_uid
 529 #endif
 530
 531 #ifndef find_last_dir_sep
 532 static inline char *git_find_last_dir_sep(const char *path)
 533 {
 534         return strrchr(path, '/');
 535 }
 536 #define find_last_dir_sep git_find_last_dir_sep
 537 #endif
 538
 539 #ifndef has_dir_sep
 540 static inline int git_has_dir_sep(const char *path)
 541 {
 542         return !!strchr(path, '/');
 543 }
 544 #define has_dir_sep(path) git_has_dir_sep(path)
 545 #endif
 546
 547 #ifndef query_user_email
 548 #define query_user_email() NULL
 549 #endif
 550
 551 #ifdef __TANDEM
 552 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 553 #include <floss.h(floss_getpwuid)>
 554 #ifndef NSIG
 555 /*
 556  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 557  * known, by detective work using kill -l as a list is all signals
 558  * instead of signal.h where it should be.
 559  */
 560 # define NSIG 100
 561 #endif
 562 #endif
 563
 564 #if defined(__HP_cc) && (__HP_cc >= 61000)
 565 #define NORETURN __attribute__((noreturn))
 566 #define NORETURN_PTR
 567 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 568 #define NORETURN __attribute__((__noreturn__))
 569 #define NORETURN_PTR __attribute__((__noreturn__))
 570 #elif defined(_MSC_VER)
 571 #define NORETURN __declspec(noreturn)
 572 #define NORETURN_PTR
 573 #else
 574 #define NORETURN
 575 #define NORETURN_PTR
 576 #ifndef __GNUC__
 577 #ifndef __attribute__
 578 #define __attribute__(x)
 579 #endif
 580 #endif
 581 #endif
 582
 583 /* The sentinel attribute is valid from gcc version 4.0 */
 584 #if defined(__GNUC__) && (__GNUC__ >= 4)
 585 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 586 /* warn_unused_result exists as of gcc 3.4.0, but be lazy and check 4.0 */
 587 #define RESULT_MUST_BE_USED __attribute__ ((warn_unused_result))
 588 #else
 589 #define LAST_ARG_MUST_BE_NULL
 590 #define RESULT_MUST_BE_USED
 591 #endif
 592
 593 #define MAYBE_UNUSED __attribute__((__unused__))
 594
 595 #include "compat/bswap.h"
 596
 597 #include "wildmatch.h"
 598
 599 struct strbuf;
 600
 601 /* General helper functions */
 602 NORETURN void usage(const char *err);
 603 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 604 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 605 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 606 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
 607 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 608 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 609 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 610 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 611 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 612
 613 #ifndef NO_OPENSSL
 614 #ifdef APPLE_COMMON_CRYPTO
 615 #include "compat/apple-common-crypto.h"
 616 #else
 617 #include <openssl/evp.h>
 618 #include <openssl/hmac.h>
 619 #endif /* APPLE_COMMON_CRYPTO */
 620 #include <openssl/x509v3.h>
 621 #endif /* NO_OPENSSL */
 622
 623 #ifdef HAVE_OPENSSL_CSPRNG
 624 #include <openssl/rand.h>
 625 #endif
 626
 627 /*
 628  * Let callers be aware of the constant return value; this can help
 629  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 630  * because other compilers may be confused by this.
 631  */
 632 #if defined(__GNUC__)
 633 static inline int const_error(void)
 634 {
 635         return -1;
 636 }
 637 #define error(...) (error(__VA_ARGS__), const_error())
 638 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 639 #endif
 640
 641 typedef void (*report_fn)(const char *, va_list params);
 642
 643 void set_die_routine(NORETURN_PTR report_fn routine);
 644 report_fn get_die_message_routine(void);
 645 void set_error_routine(report_fn routine);
 646 report_fn get_error_routine(void);
 647 void set_warn_routine(report_fn routine);
 648 report_fn get_warn_routine(void);
 649 void set_die_is_recursing_routine(int (*routine)(void));
 650
 651 int starts_with(const char *str, const char *prefix);
 652 int istarts_with(const char *str, const char *prefix);
 653
 654 /*
 655  * If the string "str" begins with the string found in "prefix", return 1.
 656  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 657  * the string right after the prefix).
 658  *
 659  * Otherwise, return 0 and leave "out" untouched.
 660  *
 661  * Examples:
 662  *
 663  *   [extract branch name, fail if not a branch]
 664  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 665  *      return -1;
 666  *
 667  *   [skip prefix if present, otherwise use whole string]
 668  *   skip_prefix(name, "refs/heads/", &name);
 669  */
 670 static inline int skip_prefix(const char *str, const char *prefix,
 671                               const char **out)
 672 {
 673         do {
 674                 if (!*prefix) {
 675                         *out = str;
 676                         return 1;
 677                 }
 678         } while (*str++ == *prefix++);
 679         return 0;
 680 }
 681
 682 /*
 683  * If the string "str" is the same as the string in "prefix", then the "arg"
 684  * parameter is set to the "def" parameter and 1 is returned.
 685  * If the string "str" begins with the string found in "prefix" and then a
 686  * "=" sign, then the "arg" parameter is set to "str + strlen(prefix) + 1"
 687  * (i.e., to the point in the string right after the prefix and the "=" sign),
 688  * and 1 is returned.
 689  *
 690  * Otherwise, return 0 and leave "arg" untouched.
 691  *
 692  * When we accept both a "--key" and a "--key=<val>" option, this function
 693  * can be used instead of !strcmp(arg, "--key") and then
 694  * skip_prefix(arg, "--key=", &arg) to parse such an option.
 695  */
 696 int skip_to_optional_arg_default(const char *str, const char *prefix,
 697                                  const char **arg, const char *def);
 698
 699 static inline int skip_to_optional_arg(const char *str, const char *prefix,
 700                                        const char **arg)
 701 {
 702         return skip_to_optional_arg_default(str, prefix, arg, "");
 703 }
 704
 705 /*
 706  * Like skip_prefix, but promises never to read past "len" bytes of the input
 707  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 708  */
 709 static inline int skip_prefix_mem(const char *buf, size_t len,
 710                                   const char *prefix,
 711                                   const char **out, size_t *outlen)
 712 {
 713         size_t prefix_len = strlen(prefix);
 714         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 715                 *out = buf + prefix_len;
 716                 *outlen = len - prefix_len;
 717                 return 1;
 718         }
 719         return 0;
 720 }
 721
 722 /*
 723  * If buf ends with suffix, return 1 and subtract the length of the suffix
 724  * from *len. Otherwise, return 0 and leave *len untouched.
 725  */
 726 static inline int strip_suffix_mem(const char *buf, size_t *len,
 727                                    const char *suffix)
 728 {
 729         size_t suflen = strlen(suffix);
 730         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 731                 return 0;
 732         *len -= suflen;
 733         return 1;
 734 }
 735
 736 /*
 737  * If str ends with suffix, return 1 and set *len to the size of the string
 738  * without the suffix. Otherwise, return 0 and set *len to the size of the
 739  * string.
 740  *
 741  * Note that we do _not_ NUL-terminate str to the new length.
 742  */
 743 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 744 {
 745         *len = strlen(str);
 746         return strip_suffix_mem(str, len, suffix);
 747 }
 748
 749 static inline int ends_with(const char *str, const char *suffix)
 750 {
 751         size_t len;
 752         return strip_suffix(str, suffix, &len);
 753 }
 754
 755 #define SWAP(a, b) do {                                         \
 756         void *_swap_a_ptr = &(a);                               \
 757         void *_swap_b_ptr = &(b);                               \
 758         unsigned char _swap_buffer[sizeof(a)];                  \
 759         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 760         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 761                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 762         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 763 } while (0)
 764
 765 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 766
 767 #ifndef PROT_READ
 768 #define PROT_READ 1
 769 #define PROT_WRITE 2
 770 #define MAP_PRIVATE 1
 771 #endif
 772
 773 #define mmap git_mmap
 774 #define munmap git_munmap
 775 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 776 int git_munmap(void *start, size_t length);
 777
 778 #else /* NO_MMAP || USE_WIN32_MMAP */
 779
 780 #include <sys/mman.h>
 781
 782 #endif /* NO_MMAP || USE_WIN32_MMAP */
 783
 784 #ifdef NO_MMAP
 785
 786 /* This value must be multiple of (pagesize * 2) */
 787 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 788
 789 #else /* NO_MMAP */
 790
 791 /* This value must be multiple of (pagesize * 2) */
 792 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 793         (sizeof(void*) >= 8 \
 794                 ?  1 * 1024 * 1024 * 1024 \
 795                 : 32 * 1024 * 1024)
 796
 797 #endif /* NO_MMAP */
 798
 799 #ifndef MAP_FAILED
 800 #define MAP_FAILED ((void *)-1)
 801 #endif
 802
 803 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 804 #define on_disk_bytes(st) ((st).st_size)
 805 #else
 806 #define on_disk_bytes(st) ((st).st_blocks * 512)
 807 #endif
 808
 809 #ifdef NEEDS_MODE_TRANSLATION
 810 #undef S_IFMT
 811 #undef S_IFREG
 812 #undef S_IFDIR
 813 #undef S_IFLNK
 814 #undef S_IFBLK
 815 #undef S_IFCHR
 816 #undef S_IFIFO
 817 #undef S_IFSOCK
 818 #define S_IFMT   0170000
 819 #define S_IFREG  0100000
 820 #define S_IFDIR  0040000
 821 #define S_IFLNK  0120000
 822 #define S_IFBLK  0060000
 823 #define S_IFCHR  0020000
 824 #define S_IFIFO  0010000
 825 #define S_IFSOCK 0140000
 826 #ifdef stat
 827 #undef stat
 828 #endif
 829 #define stat(path, buf) git_stat(path, buf)
 830 int git_stat(const char *, struct stat *);
 831 #ifdef fstat
 832 #undef fstat
 833 #endif
 834 #define fstat(fd, buf) git_fstat(fd, buf)
 835 int git_fstat(int, struct stat *);
 836 #ifdef lstat
 837 #undef lstat
 838 #endif
 839 #define lstat(path, buf) git_lstat(path, buf)
 840 int git_lstat(const char *, struct stat *);
 841 #endif
 842
 843 #define DEFAULT_PACKED_GIT_LIMIT \
 844         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 845
 846 #ifdef NO_PREAD
 847 #define pread git_pread
 848 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 849 #endif
 850 /*
 851  * Forward decl that will remind us if its twin in cache.h changes.
 852  * This function is used in compat/pread.c.  But we can't include
 853  * cache.h there.
 854  */
 855 ssize_t read_in_full(int fd, void *buf, size_t count);
 856
 857 #ifdef NO_SETENV
 858 #define setenv gitsetenv
 859 int gitsetenv(const char *, const char *, int);
 860 #endif
 861
 862 #ifdef NO_MKDTEMP
 863 #define mkdtemp gitmkdtemp
 864 char *gitmkdtemp(char *);
 865 #endif
 866
 867 #ifdef NO_UNSETENV
 868 #define unsetenv gitunsetenv
 869 int gitunsetenv(const char *);
 870 #endif
 871
 872 #ifdef NO_STRCASESTR
 873 #define strcasestr gitstrcasestr
 874 char *gitstrcasestr(const char *haystack, const char *needle);
 875 #endif
 876
 877 #ifdef NO_STRLCPY
 878 #define strlcpy gitstrlcpy
 879 size_t gitstrlcpy(char *, const char *, size_t);
 880 #endif
 881
 882 #ifdef NO_STRTOUMAX
 883 #define strtoumax gitstrtoumax
 884 uintmax_t gitstrtoumax(const char *, char **, int);
 885 #define strtoimax gitstrtoimax
 886 intmax_t gitstrtoimax(const char *, char **, int);
 887 #endif
 888
 889 #ifdef NO_HSTRERROR
 890 #define hstrerror githstrerror
 891 const char *githstrerror(int herror);
 892 #endif
 893
 894 #ifdef NO_MEMMEM
 895 #define memmem gitmemmem
 896 void *gitmemmem(const void *haystack, size_t haystacklen,
 897                 const void *needle, size_t needlelen);
 898 #endif
 899
 900 #ifdef OVERRIDE_STRDUP
 901 #ifdef strdup
 902 #undef strdup
 903 #endif
 904 #define strdup gitstrdup
 905 char *gitstrdup(const char *s);
 906 #endif
 907
 908 #ifdef NO_GETPAGESIZE
 909 #define getpagesize() sysconf(_SC_PAGESIZE)
 910 #endif
 911
 912 #ifndef O_CLOEXEC
 913 #define O_CLOEXEC 0
 914 #endif
 915
 916 #ifdef FREAD_READS_DIRECTORIES
 917 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 918 #  ifdef fopen
 919 #   undef fopen
 920 #  endif
 921 #  define fopen(a,b) git_fopen(a,b)
 922 # endif
 923 FILE *git_fopen(const char*, const char*);
 924 #endif
 925
 926 #ifdef SNPRINTF_RETURNS_BOGUS
 927 #ifdef snprintf
 928 #undef snprintf
 929 #endif
 930 #define snprintf git_snprintf
 931 int git_snprintf(char *str, size_t maxsize,
 932                  const char *format, ...);
 933 #ifdef vsnprintf
 934 #undef vsnprintf
 935 #endif
 936 #define vsnprintf git_vsnprintf
 937 int git_vsnprintf(char *str, size_t maxsize,
 938                   const char *format, va_list ap);
 939 #endif
 940
 941 #ifdef OPEN_RETURNS_EINTR
 942 #undef open
 943 #define open git_open_with_retry
 944 int git_open_with_retry(const char *path, int flag, ...);
 945 #endif
 946
 947 #ifdef __GLIBC_PREREQ
 948 #if __GLIBC_PREREQ(2, 1)
 949 #define HAVE_STRCHRNUL
 950 #endif
 951 #endif
 952
 953 #ifndef HAVE_STRCHRNUL
 954 #define strchrnul gitstrchrnul
 955 static inline char *gitstrchrnul(const char *s, int c)
 956 {
 957         while (*s && *s != c)
 958                 s++;
 959         return (char *)s;
 960 }
 961 #endif
 962
 963 #ifdef NO_INET_PTON
 964 int inet_pton(int af, const char *src, void *dst);
 965 #endif
 966
 967 #ifdef NO_INET_NTOP
 968 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 969 #endif
 970
 971 #ifdef NO_PTHREADS
 972 #define atexit git_atexit
 973 int git_atexit(void (*handler)(void));
 974 #endif
 975
 976 static inline size_t st_add(size_t a, size_t b)
 977 {
 978         if (unsigned_add_overflows(a, b))
 979                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 980                     (uintmax_t)a, (uintmax_t)b);
 981         return a + b;
 982 }
 983 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 984 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 985
 986 static inline size_t st_mult(size_t a, size_t b)
 987 {
 988         if (unsigned_mult_overflows(a, b))
 989                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 990                     (uintmax_t)a, (uintmax_t)b);
 991         return a * b;
 992 }
 993
 994 static inline size_t st_sub(size_t a, size_t b)
 995 {
 996         if (a < b)
 997                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 998                     (uintmax_t)a, (uintmax_t)b);
 999         return a - b;
1000 }
1001
1002 static inline size_t st_left_shift(size_t a, unsigned shift)
1003 {
1004         if (unsigned_left_shift_overflows(a, shift))
1005                 die("size_t overflow: %"PRIuMAX" << %u",
1006                     (uintmax_t)a, shift);
1007         return a << shift;
1008 }
1009
1010 static inline unsigned long cast_size_t_to_ulong(size_t a)
1011 {
1012         if (a != (unsigned long)a)
1013                 die("object too large to read on this platform: %"
1014                     PRIuMAX" is cut off to %lu",
1015                     (uintmax_t)a, (unsigned long)a);
1016         return (unsigned long)a;
1017 }
1018
1019 /*
1020  * Limit size of IO chunks, because huge chunks only cause pain.  OS X
1021  * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
1022  * the absence of bugs, large chunks can result in bad latencies when
1023  * you decide to kill the process.
1024  *
1025  * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
1026  * that is smaller than that, clip it to SSIZE_MAX, as a call to
1027  * read(2) or write(2) larger than that is allowed to fail.  As the last
1028  * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
1029  * to override this, if the definition of SSIZE_MAX given by the platform
1030  * is broken.
1031  */
1032 #ifndef MAX_IO_SIZE
1033 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
1034 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
1035 #  define MAX_IO_SIZE SSIZE_MAX
1036 # else
1037 #  define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
1038 # endif
1039 #endif
1040
1041 #ifdef HAVE_ALLOCA_H
1042 # include <alloca.h>
1043 # define xalloca(size)      (alloca(size))
1044 # define xalloca_free(p)    do {} while (0)
1045 #else
1046 # define xalloca(size)      (xmalloc(size))
1047 # define xalloca_free(p)    (free(p))
1048 #endif
1049 char *xstrdup(const char *str);
1050 void *xmalloc(size_t size);
1051 void *xmallocz(size_t size);
1052 void *xmallocz_gently(size_t size);
1053 void *xmemdupz(const void *data, size_t len);
1054 char *xstrndup(const char *str, size_t len);
1055 void *xrealloc(void *ptr, size_t size);
1056 void *xcalloc(size_t nmemb, size_t size);
1057 void xsetenv(const char *name, const char *value, int overwrite);
1058 void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1059 const char *mmap_os_err(void);
1060 void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
1061 int xopen(const char *path, int flags, ...);
1062 ssize_t xread(int fd, void *buf, size_t len);
1063 ssize_t xwrite(int fd, const void *buf, size_t len);
1064 ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
1065 int xdup(int fd);
1066 FILE *xfopen(const char *path, const char *mode);
1067 FILE *xfdopen(int fd, const char *mode);
1068 int xmkstemp(char *temp_filename);
1069 int xmkstemp_mode(char *temp_filename, int mode);
1070 char *xgetcwd(void);
1071 FILE *fopen_for_writing(const char *path);
1072 FILE *fopen_or_warn(const char *path, const char *mode);
1073
1074 /*
1075  * Like strncmp, but only return zero if s is NUL-terminated and exactly len
1076  * characters long.  If it is not, consider it greater than t.
1077  */
1078 int xstrncmpz(const char *s, const char *t, size_t len);
1079
1080 /*
1081  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
1082  * that ptr is used twice, so don't pass e.g. ptr++.
1083  */
1084 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
1085
1086 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
1087 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
1088 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
1089
1090 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
1091         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1092 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
1093 {
1094         if (n)
1095                 memcpy(dst, src, st_mult(size, n));
1096 }
1097
1098 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
1099         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
1100 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
1101 {
1102         if (n)
1103                 memmove(dst, src, st_mult(size, n));
1104 }
1105
1106 /*
1107  * These functions help you allocate structs with flex arrays, and copy
1108  * the data directly into the array. For example, if you had:
1109  *
1110  *   struct foo {
1111  *     int bar;
1112  *     char name[FLEX_ARRAY];
1113  *   };
1114  *
1115  * you can do:
1116  *
1117  *   struct foo *f;
1118  *   FLEX_ALLOC_MEM(f, name, src, len);
1119  *
1120  * to allocate a "foo" with the contents of "src" in the "name" field.
1121  * The resulting struct is automatically zero'd, and the flex-array field
1122  * is NUL-terminated (whether the incoming src buffer was or not).
1123  *
1124  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1125  * but do want to store a pointer to some extra data in the same allocated
1126  * block. For example, if you have:
1127  *
1128  *   struct foo {
1129  *     char *name;
1130  *     int bar;
1131  *   };
1132  *
1133  * you can do:
1134  *
1135  *   struct foo *f;
1136  *   FLEXPTR_ALLOC_STR(f, name, src);
1137  *
1138  * and "name" will point to a block of memory after the struct, which will be
1139  * freed along with the struct (but the pointer can be repointed anywhere).
1140  *
1141  * The *_STR variants accept a string parameter rather than a ptr/len
1142  * combination.
1143  *
1144  * Note that these macros will evaluate the first parameter multiple
1145  * times, and it must be assignable as an lvalue.
1146  */
1147 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1148         size_t flex_array_len_ = (len); \
1149         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1150         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1151 } while (0)
1152 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1153         size_t flex_array_len_ = (len); \
1154         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1155         memcpy((x) + 1, (buf), flex_array_len_); \
1156         (x)->ptrname = (void *)((x)+1); \
1157 } while(0)
1158 #define FLEX_ALLOC_STR(x, flexname, str) \
1159         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1160 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1161         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1162
1163 static inline char *xstrdup_or_null(const char *str)
1164 {
1165         return str ? xstrdup(str) : NULL;
1166 }
1167
1168 static inline size_t xsize_t(off_t len)
1169 {
1170         if (len < 0 || (uintmax_t) len > SIZE_MAX)
1171                 die("Cannot handle files this big");
1172         return (size_t) len;
1173 }
1174
1175 __attribute__((format (printf, 3, 4)))
1176 int xsnprintf(char *dst, size_t max, const char *fmt, ...);
1177
1178 #ifndef HOST_NAME_MAX
1179 #define HOST_NAME_MAX 256
1180 #endif
1181
1182 int xgethostname(char *buf, size_t len);
1183
1184 /* in ctype.c, for kwset users */
1185 extern const unsigned char tolower_trans_tbl[256];
1186
1187 /* Sane ctype - no locale, and works with signed chars */
1188 #undef isascii
1189 #undef isspace
1190 #undef isdigit
1191 #undef isalpha
1192 #undef isalnum
1193 #undef isprint
1194 #undef islower
1195 #undef isupper
1196 #undef tolower
1197 #undef toupper
1198 #undef iscntrl
1199 #undef ispunct
1200 #undef isxdigit
1201
1202 extern const unsigned char sane_ctype[256];
1203 #define GIT_SPACE 0x01
1204 #define GIT_DIGIT 0x02
1205 #define GIT_ALPHA 0x04
1206 #define GIT_GLOB_SPECIAL 0x08
1207 #define GIT_REGEX_SPECIAL 0x10
1208 #define GIT_PATHSPEC_MAGIC 0x20
1209 #define GIT_CNTRL 0x40
1210 #define GIT_PUNCT 0x80
1211 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
1212 #define isascii(x) (((x) & ~0x7f) == 0)
1213 #define isspace(x) sane_istest(x,GIT_SPACE)
1214 #define isdigit(x) sane_istest(x,GIT_DIGIT)
1215 #define isalpha(x) sane_istest(x,GIT_ALPHA)
1216 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
1217 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
1218 #define islower(x) sane_iscase(x, 1)
1219 #define isupper(x) sane_iscase(x, 0)
1220 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
1221 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
1222 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
1223 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
1224                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
1225 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
1226 #define tolower(x) sane_case((unsigned char)(x), 0x20)
1227 #define toupper(x) sane_case((unsigned char)(x), 0)
1228 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
1229
1230 static inline int sane_case(int x, int high)
1231 {
1232         if (sane_istest(x, GIT_ALPHA))
1233                 x = (x & ~0x20) | high;
1234         return x;
1235 }
1236
1237 static inline int sane_iscase(int x, int is_lower)
1238 {
1239         if (!sane_istest(x, GIT_ALPHA))
1240                 return 0;
1241
1242         if (is_lower)
1243                 return (x & 0x20) != 0;
1244         else
1245                 return (x & 0x20) == 0;
1246 }
1247
1248 /*
1249  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1250  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1251  * locale-specific conversions).
1252  */
1253 static inline int skip_iprefix(const char *str, const char *prefix,
1254                                const char **out)
1255 {
1256         do {
1257                 if (!*prefix) {
1258                         *out = str;
1259                         return 1;
1260                 }
1261         } while (tolower(*str++) == tolower(*prefix++));
1262         return 0;
1263 }
1264
1265 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1266 {
1267         unsigned long ul;
1268         char *p;
1269
1270         errno = 0;
1271         /* negative values would be accepted by strtoul */
1272         if (strchr(s, '-'))
1273                 return -1;
1274         ul = strtoul(s, &p, base);
1275         if (errno || *p || p == s || (unsigned int) ul != ul)
1276                 return -1;
1277         *result = ul;
1278         return 0;
1279 }
1280
1281 static inline int strtol_i(char const *s, int base, int *result)
1282 {
1283         long ul;
1284         char *p;
1285
1286         errno = 0;
1287         ul = strtol(s, &p, base);
1288         if (errno || *p || p == s || (int) ul != ul)
1289                 return -1;
1290         *result = ul;
1291         return 0;
1292 }
1293
1294 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1295                       int(*compar)(const void *, const void *));
1296 #ifdef INTERNAL_QSORT
1297 #define qsort git_stable_qsort
1298 #endif
1299
1300 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1301 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1302                               int(*compar)(const void *, const void *))
1303 {
1304         if (nmemb > 1)
1305                 qsort(base, nmemb, size, compar);
1306 }
1307
1308 #define STABLE_QSORT(base, n, compar) \
1309         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1310
1311 #ifndef HAVE_ISO_QSORT_S
1312 int git_qsort_s(void *base, size_t nmemb, size_t size,
1313                 int (*compar)(const void *, const void *, void *), void *ctx);
1314 #define qsort_s git_qsort_s
1315 #endif
1316
1317 #define QSORT_S(base, n, compar, ctx) do {                      \
1318         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1319                 BUG("qsort_s() failed");                        \
1320 } while (0)
1321
1322 #ifndef REG_STARTEND
1323 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1324 #endif
1325
1326 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1327                               size_t nmatch, regmatch_t pmatch[], int eflags)
1328 {
1329         assert(nmatch > 0 && pmatch);
1330         pmatch[0].rm_so = 0;
1331         pmatch[0].rm_eo = size;
1332         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1333 }
1334
1335 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1336 # define FORCE_DIR_SET_GID S_ISGID
1337 #else
1338 # define FORCE_DIR_SET_GID 0
1339 #endif
1340
1341 #ifdef NO_NSEC
1342 #undef USE_NSEC
1343 #define ST_CTIME_NSEC(st) 0
1344 #define ST_MTIME_NSEC(st) 0
1345 #else
1346 #ifdef USE_ST_TIMESPEC
1347 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1348 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1349 #else
1350 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1351 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1352 #endif
1353 #endif
1354
1355 #ifdef UNRELIABLE_FSTAT
1356 #define fstat_is_reliable() 0
1357 #else
1358 #define fstat_is_reliable() 1
1359 #endif
1360
1361 #ifndef va_copy
1362 /*
1363  * Since an obvious implementation of va_list would be to make it a
1364  * pointer into the stack frame, a simple assignment will work on
1365  * many systems.  But let's try to be more portable.
1366  */
1367 #ifdef __va_copy
1368 #define va_copy(dst, src) __va_copy(dst, src)
1369 #else
1370 #define va_copy(dst, src) ((dst) = (src))
1371 #endif
1372 #endif
1373
1374 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1375 extern int BUG_exit_code;
1376
1377 /* usage.c: if bug() is called we should have a BUG_if_bug() afterwards */
1378 extern int bug_called_must_BUG;
1379
1380 __attribute__((format (printf, 3, 4))) NORETURN
1381 void BUG_fl(const char *file, int line, const char *fmt, ...);
1382 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1383 __attribute__((format (printf, 3, 4)))
1384 void bug_fl(const char *file, int line, const char *fmt, ...);
1385 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)
1386 #define BUG_if_bug(...) do { \
1387         if (bug_called_must_BUG) \
1388                 BUG_fl(__FILE__, __LINE__, __VA_ARGS__); \
1389 } while (0)
1390
1391 #ifndef FSYNC_METHOD_DEFAULT
1392 #ifdef __APPLE__
1393 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_WRITEOUT_ONLY
1394 #else
1395 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_FSYNC
1396 #endif
1397 #endif
1398
1399 enum fsync_action {
1400         FSYNC_WRITEOUT_ONLY,
1401         FSYNC_HARDWARE_FLUSH
1402 };
1403
1404 /*
1405  * Issues an fsync against the specified file according to the specified mode.
1406  *
1407  * FSYNC_WRITEOUT_ONLY attempts to use interfaces available on some operating
1408  * systems to flush the OS cache without issuing a flush command to the storage
1409  * controller. If those interfaces are unavailable, the function fails with
1410  * ENOSYS.
1411  *
1412  * FSYNC_HARDWARE_FLUSH does an OS writeout and hardware flush to ensure that
1413  * changes are durable. It is not expected to fail.
1414  */
1415 int git_fsync(int fd, enum fsync_action action);
1416
1417 /*
1418  * Writes out trace statistics for fsync using the trace2 API.
1419  */
1420 void trace_git_fsync_stats(void);
1421
1422 /*
1423  * Preserves errno, prints a message, but gives no warning for ENOENT.
1424  * Returns 0 on success, which includes trying to unlink an object that does
1425  * not exist.
1426  */
1427 int unlink_or_warn(const char *path);
1428  /*
1429   * Tries to unlink file.  Returns 0 if unlink succeeded
1430   * or the file already didn't exist.  Returns -1 and
1431   * appends a message to err suitable for
1432   * 'error("%s", err->buf)' on error.
1433   */
1434 int unlink_or_msg(const char *file, struct strbuf *err);
1435 /*
1436  * Preserves errno, prints a message, but gives no warning for ENOENT.
1437  * Returns 0 on success, which includes trying to remove a directory that does
1438  * not exist.
1439  */
1440 int rmdir_or_warn(const char *path);
1441 /*
1442  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1443  * the supplied file mode.
1444  */
1445 int remove_or_warn(unsigned int mode, const char *path);
1446
1447 /*
1448  * Call access(2), but warn for any error except "missing file"
1449  * (ENOENT or ENOTDIR).
1450  */
1451 #define ACCESS_EACCES_OK (1U << 0)
1452 int access_or_warn(const char *path, int mode, unsigned flag);
1453 int access_or_die(const char *path, int mode, unsigned flag);
1454
1455 /* Warn on an inaccessible file if errno indicates this is an error */
1456 int warn_on_fopen_errors(const char *path);
1457
1458 /*
1459  * Open with O_NOFOLLOW, or equivalent. Note that the fallback equivalent
1460  * may be racy. Do not use this as protection against an attacker who can
1461  * simultaneously create paths.
1462  */
1463 int open_nofollow(const char *path, int flags);
1464
1465 #ifndef SHELL_PATH
1466 # define SHELL_PATH "/bin/sh"
1467 #endif
1468
1469 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1470 static inline void flockfile(FILE *fh)
1471 {
1472         ; /* nothing */
1473 }
1474 static inline void funlockfile(FILE *fh)
1475 {
1476         ; /* nothing */
1477 }
1478 #define getc_unlocked(fh) getc(fh)
1479 #endif
1480
1481 #ifdef FILENO_IS_A_MACRO
1482 int git_fileno(FILE *stream);
1483 # ifndef COMPAT_CODE_FILENO
1484 #  undef fileno
1485 #  define fileno(p) git_fileno(p)
1486 # endif
1487 #endif
1488
1489 #ifdef NEED_ACCESS_ROOT_HANDLER
1490 int git_access(const char *path, int mode);
1491 # ifndef COMPAT_CODE_ACCESS
1492 #  ifdef access
1493 #  undef access
1494 #  endif
1495 #  define access(path, mode) git_access(path, mode)
1496 # endif
1497 #endif
1498
1499 /*
1500  * Our code often opens a path to an optional file, to work on its
1501  * contents when we can successfully open it.  We can ignore a failure
1502  * to open if such an optional file does not exist, but we do want to
1503  * report a failure in opening for other reasons (e.g. we got an I/O
1504  * error, or the file is there, but we lack the permission to open).
1505  *
1506  * Call this function after seeing an error from open() or fopen() to
1507  * see if the errno indicates a missing file that we can safely ignore.
1508  */
1509 static inline int is_missing_file_error(int errno_)
1510 {
1511         return (errno_ == ENOENT || errno_ == ENOTDIR);
1512 }
1513
1514 int cmd_main(int, const char **);
1515
1516 /*
1517  * Intercept all calls to exit() and route them to trace2 to
1518  * optionally emit a message before calling the real exit().
1519  */
1520 int common_exit(const char *file, int line, int code);
1521 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
1522
1523 /*
1524  * You can mark a stack variable with UNLEAK(var) to avoid it being
1525  * reported as a leak by tools like LSAN or valgrind. The argument
1526  * should generally be the variable itself (not its address and not what
1527  * it points to). It's safe to use this on pointers which may already
1528  * have been freed, or on pointers which may still be in use.
1529  *
1530  * Use this _only_ for a variable that leaks by going out of scope at
1531  * program exit (so only from cmd_* functions or their direct helpers).
1532  * Normal functions, especially those which may be called multiple
1533  * times, should actually free their memory. This is only meant as
1534  * an annotation, and does nothing in non-leak-checking builds.
1535  */
1536 #ifdef SUPPRESS_ANNOTATED_LEAKS
1537 void unleak_memory(const void *ptr, size_t len);
1538 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1539 #else
1540 #define UNLEAK(var) do {} while (0)
1541 #endif
1542
1543 #define z_const
1544 #include <zlib.h>
1545
1546 #if ZLIB_VERNUM < 0x1290
1547 /*
1548  * This is uncompress2, which is only available in zlib >= 1.2.9
1549  * (released as of early 2017). See compat/zlib-uncompress2.c.
1550  */
1551 int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
1552                 uLong *sourceLen);
1553 #endif
1554
1555 /*
1556  * This include must come after system headers, since it introduces macros that
1557  * replace system names.
1558  */
1559 #include "banned.h"
1560
1561 /*
1562  * container_of - Get the address of an object containing a field.
1563  *
1564  * @ptr: pointer to the field.
1565  * @type: type of the object.
1566  * @member: name of the field within the object.
1567  */
1568 #define container_of(ptr, type, member) \
1569         ((type *) ((char *)(ptr) - offsetof(type, member)))
1570
1571 /*
1572  * helper function for `container_of_or_null' to avoid multiple
1573  * evaluation of @ptr
1574  */
1575 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1576 {
1577         return ptr ? (char *)ptr - offset : NULL;
1578 }
1579
1580 /*
1581  * like `container_of', but allows returned value to be NULL
1582  */
1583 #define container_of_or_null(ptr, type, member) \
1584         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1585
1586 /*
1587  * like offsetof(), but takes a pointer to a variable of type which
1588  * contains @member, instead of a specified type.
1589  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1590  * everywhere.
1591  */
1592 #if defined(__GNUC__) /* clang sets this, too */
1593 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1594 #else /* !__GNUC__ */
1595 #define OFFSETOF_VAR(ptr, member) \
1596         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1597 #endif /* !__GNUC__ */
1598
1599 void sleep_millisec(int millisec);
1600
1601 /*
1602  * Generate len bytes from the system cryptographically secure PRNG.
1603  * Returns 0 on success and -1 on error, setting errno.  The inability to
1604  * satisfy the full request is an error.
1605  */
1606 int csprng_bytes(void *buf, size_t len);
1607
1608 #endif