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