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