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 # define BARF_UNLESS_COPYABLE(dst, src) \
 101         BUILD_ASSERT_OR_ZERO(__builtin_types_compatible_p(__typeof__(*(dst)), \
 102                                                           __typeof__(*(src))))
 103 #else
 104 # define BARF_UNLESS_AN_ARRAY(arr) 0
 105 # define BARF_UNLESS_COPYABLE(dst, src) \
 106         BUILD_ASSERT_OR_ZERO(0 ? ((*(dst) = *(src)), 0) : \
 107                                  sizeof(*(dst)) == sizeof(*(src)))
 108 #endif
 109 /*
 110  * ARRAY_SIZE - get the number of elements in a visible array
 111  * @x: the array whose size you want.
 112  *
 113  * This does not work on pointers, or arrays declared as [], or
 114  * function parameters.  With correct compiler support, such usage
 115  * will cause a build error (see the build_assert_or_zero macro).
 116  */
 117 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
 118
 119 #define bitsizeof(x)  (CHAR_BIT * sizeof(x))
 120
 121 #define maximum_signed_value_of_type(a) \
 122     (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
 123
 124 #define maximum_unsigned_value_of_type(a) \
 125     (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
 126
 127 /*
 128  * Signed integer overflow is undefined in C, so here's a helper macro
 129  * to detect if the sum of two integers will overflow.
 130  *
 131  * Requires: a >= 0, typeof(a) equals typeof(b)
 132  */
 133 #define signed_add_overflows(a, b) \
 134     ((b) > maximum_signed_value_of_type(a) - (a))
 135
 136 #define unsigned_add_overflows(a, b) \
 137     ((b) > maximum_unsigned_value_of_type(a) - (a))
 138
 139 /*
 140  * Returns true if the multiplication of "a" and "b" will
 141  * overflow. The types of "a" and "b" must match and must be unsigned.
 142  * Note that this macro evaluates "a" twice!
 143  */
 144 #define unsigned_mult_overflows(a, b) \
 145     ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
 146
 147 /*
 148  * Returns true if the left shift of "a" by "shift" bits will
 149  * overflow. The type of "a" must be unsigned.
 150  */
 151 #define unsigned_left_shift_overflows(a, shift) \
 152     ((shift) < bitsizeof(a) && \
 153      (a) > maximum_unsigned_value_of_type(a) >> (shift))
 154
 155 #ifdef __GNUC__
 156 #define TYPEOF(x) (__typeof__(x))
 157 #else
 158 #define TYPEOF(x)
 159 #endif
 160
 161 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 162 #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 163
 164 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 165
 166 /* Approximation of the length of the decimal representation of this type. */
 167 #define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 168
 169 #ifdef __MINGW64__
 170 #define _POSIX_C_SOURCE 1
 171 #elif defined(__sun__)
 172  /*
 173   * On Solaris, when _XOPEN_EXTENDED is set, its header file
 174   * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 175   * setting to say we are XPG5 or XPG6.  Also on Solaris,
 176   * XPG6 programs must be compiled with a c99 compiler, while
 177   * non XPG6 programs must be compiled with a pre-c99 compiler.
 178   */
 179 # if __STDC_VERSION__ - 0 >= 199901L
 180 # define _XOPEN_SOURCE 600
 181 # else
 182 # define _XOPEN_SOURCE 500
 183 # endif
 184 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 185       !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 186       !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
 187       !defined(__CYGWIN__)
 188 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 189 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 190 #endif
 191 #define _ALL_SOURCE 1
 192 #define _GNU_SOURCE 1
 193 #define _BSD_SOURCE 1
 194 #define _DEFAULT_SOURCE 1
 195 #define _NETBSD_SOURCE 1
 196 #define _SGI_SOURCE 1
 197
 198 #if GIT_GNUC_PREREQ(4, 5)
 199 #define UNUSED __attribute__((unused)) \
 200         __attribute__((deprecated ("parameter declared as UNUSED")))
 201 #elif defined(__GNUC__)
 202 #define UNUSED __attribute__((unused)) \
 203         __attribute__((deprecated))
 204 #else
 205 #define UNUSED
 206 #endif
 207
 208 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 209 # if !defined(_WIN32_WINNT)
 210 #  define _WIN32_WINNT 0x0600
 211 # endif
 212 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 213 #include <winsock2.h>
 214 #ifndef NO_UNIX_SOCKETS
 215 #include <afunix.h>
 216 #endif
 217 #include <windows.h>
 218 #define GIT_WINDOWS_NATIVE
 219 #endif
 220
 221 #include <unistd.h>
 222 #include <stdio.h>
 223 #include <sys/stat.h>
 224 #include <fcntl.h>
 225 #include <stddef.h>
 226 #include <stdlib.h>
 227 #include <stdarg.h>
 228 #include <stdbool.h>
 229 #include <string.h>
 230 #ifdef HAVE_STRINGS_H
 231 #include <strings.h> /* for strcasecmp() */
 232 #endif
 233 #include <errno.h>
 234 #include <limits.h>
 235 #include <locale.h>
 236 #ifdef NEEDS_SYS_PARAM_H
 237 #include <sys/param.h>
 238 #endif
 239 #include <sys/types.h>
 240 #include <dirent.h>
 241 #include <sys/time.h>
 242 #include <time.h>
 243 #include <signal.h>
 244 #include <assert.h>
 245 #include <regex.h>
 246 #include <utime.h>
 247 #include <syslog.h>
 248 #if !defined(NO_POLL_H)
 249 #include <poll.h>
 250 #elif !defined(NO_SYS_POLL_H)
 251 #include <sys/poll.h>
 252 #else
 253 /* Pull the compat stuff */
 254 #include <poll.h>
 255 #endif
 256 #ifdef HAVE_BSD_SYSCTL
 257 #include <sys/sysctl.h>
 258 #endif
 259
 260 /* Used by compat/win32/path-utils.h, and more */
 261 static inline int is_xplatform_dir_sep(int c)
 262 {
 263         return c == '/' || c == '\\';
 264 }
 265
 266 #if defined(__CYGWIN__)
 267 #include "compat/win32/path-utils.h"
 268 #endif
 269 #if defined(__MINGW32__)
 270 /* pull in Windows compatibility stuff */
 271 #include "compat/win32/path-utils.h"
 272 #include "compat/mingw.h"
 273 #elif defined(_MSC_VER)
 274 #include "compat/win32/path-utils.h"
 275 #include "compat/msvc.h"
 276 #else
 277 #include <sys/utsname.h>
 278 #include <sys/wait.h>
 279 #include <sys/resource.h>
 280 #include <sys/socket.h>
 281 #include <sys/ioctl.h>
 282 #include <sys/statvfs.h>
 283 #include <termios.h>
 284 #ifndef NO_SYS_SELECT_H
 285 #include <sys/select.h>
 286 #endif
 287 #include <netinet/in.h>
 288 #include <netinet/tcp.h>
 289 #include <arpa/inet.h>
 290 #include <netdb.h>
 291 #include <pwd.h>
 292 #include <sys/un.h>
 293 #ifndef NO_INTTYPES_H
 294 #include <inttypes.h>
 295 #else
 296 #include <stdint.h>
 297 #endif
 298 #ifdef HAVE_ARC4RANDOM_LIBBSD
 299 #include <bsd/stdlib.h>
 300 #endif
 301 #ifdef HAVE_GETRANDOM
 302 #include <sys/random.h>
 303 #endif
 304 #ifdef NO_INTPTR_T
 305 /*
 306  * On I16LP32, ILP32 and LP64 "long" is the safe bet, however
 307  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 308  * while on IP16 and IP16L32 it is "int" (resp. "short")
 309  * Size needs to match (or exceed) 'sizeof(void *)'.
 310  * We can't take "long long" here as not everybody has it.
 311  */
 312 typedef long intptr_t;
 313 typedef unsigned long uintptr_t;
 314 #endif
 315 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 316 #include <grp.h>
 317 #define _ALL_SOURCE 1
 318 #endif
 319
 320 /* used on Mac OS X */
 321 #ifdef PRECOMPOSE_UNICODE
 322 #include "compat/precompose_utf8.h"
 323 #else
 324 static inline const char *precompose_argv_prefix(int argc UNUSED,
 325                                                  const char **argv UNUSED,
 326                                                  const char *prefix)
 327 {
 328         return prefix;
 329 }
 330 static inline const char *precompose_string_if_needed(const char *in)
 331 {
 332         return in;
 333 }
 334
 335 #define probe_utf8_pathname_composition()
 336 #endif
 337
 338 #ifdef MKDIR_WO_TRAILING_SLASH
 339 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 340 int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 341 #endif
 342
 343 #ifdef time
 344 #undef time
 345 #endif
 346 static inline time_t git_time(time_t *tloc)
 347 {
 348         struct timeval tv;
 349
 350         /*
 351          * Avoid time(NULL), which can disagree with gettimeofday(2)
 352          * and filesystem timestamps.
 353          */
 354         gettimeofday(&tv, NULL);
 355
 356         if (tloc)
 357                 *tloc = tv.tv_sec;
 358         return tv.tv_sec;
 359 }
 360 #define time git_time
 361
 362 #ifdef NO_STRUCT_ITIMERVAL
 363 struct itimerval {
 364         struct timeval it_interval;
 365         struct timeval it_value;
 366 };
 367 #endif
 368
 369 #ifdef NO_SETITIMER
 370 static inline int git_setitimer(int which UNUSED,
 371                                 const struct itimerval *value UNUSED,
 372                                 struct itimerval *newvalue UNUSED) {
 373         return 0; /* pretend success */
 374 }
 375 #undef setitimer
 376 #define setitimer(which,value,ovalue) git_setitimer(which,value,ovalue)
 377 #endif
 378
 379 #ifndef NO_LIBGEN_H
 380 #include <libgen.h>
 381 #else
 382 #define basename gitbasename
 383 char *gitbasename(char *);
 384 #define dirname gitdirname
 385 char *gitdirname(char *);
 386 #endif
 387
 388 #ifndef NO_ICONV
 389 #include <iconv.h>
 390 #endif
 391
 392 #ifndef NO_OPENSSL
 393 #ifdef __APPLE__
 394 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 395 #include <AvailabilityMacros.h>
 396 #undef DEPRECATED_ATTRIBUTE
 397 #define DEPRECATED_ATTRIBUTE
 398 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 399 #endif
 400 #include <openssl/ssl.h>
 401 #include <openssl/err.h>
 402 #endif
 403
 404 #ifdef HAVE_SYSINFO
 405 # include <sys/sysinfo.h>
 406 #endif
 407
 408 /* On most systems <netdb.h> would have given us this, but
 409  * not on some systems (e.g. z/OS).
 410  */
 411 #ifndef NI_MAXHOST
 412 #define NI_MAXHOST 1025
 413 #endif
 414
 415 #ifndef NI_MAXSERV
 416 #define NI_MAXSERV 32
 417 #endif
 418
 419 /* On most systems <limits.h> would have given us this, but
 420  * not on some systems (e.g. GNU/Hurd).
 421  */
 422 #ifndef PATH_MAX
 423 #define PATH_MAX 4096
 424 #endif
 425
 426 #ifndef NAME_MAX
 427 #define NAME_MAX 255
 428 #endif
 429
 430 typedef uintmax_t timestamp_t;
 431 #define PRItime PRIuMAX
 432 #define parse_timestamp strtoumax
 433 #define TIME_MAX UINTMAX_MAX
 434 #define TIME_MIN 0
 435
 436 #ifndef PATH_SEP
 437 #define PATH_SEP ':'
 438 #endif
 439
 440 #ifdef HAVE_PATHS_H
 441 #include <paths.h>
 442 #endif
 443 #ifndef _PATH_DEFPATH
 444 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 445 #endif
 446
 447 #ifndef platform_core_config
 448 struct config_context;
 449 static inline int noop_core_config(const char *var UNUSED,
 450                                    const char *value UNUSED,
 451                                    const struct config_context *ctx UNUSED,
 452                                    void *cb UNUSED)
 453 {
 454         return 0;
 455 }
 456 #define platform_core_config noop_core_config
 457 #endif
 458
 459 int lstat_cache_aware_rmdir(const char *path);
 460 #if !defined(__MINGW32__) && !defined(_MSC_VER)
 461 #define rmdir lstat_cache_aware_rmdir
 462 #endif
 463
 464 #ifndef has_dos_drive_prefix
 465 static inline int git_has_dos_drive_prefix(const char *path UNUSED)
 466 {
 467         return 0;
 468 }
 469 #define has_dos_drive_prefix git_has_dos_drive_prefix
 470 #endif
 471
 472 #ifndef skip_dos_drive_prefix
 473 static inline int git_skip_dos_drive_prefix(char **path UNUSED)
 474 {
 475         return 0;
 476 }
 477 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 478 #endif
 479
 480 static inline int git_is_dir_sep(int c)
 481 {
 482         return c == '/';
 483 }
 484 #ifndef is_dir_sep
 485 #define is_dir_sep git_is_dir_sep
 486 #endif
 487
 488 #ifndef offset_1st_component
 489 static inline int git_offset_1st_component(const char *path)
 490 {
 491         return is_dir_sep(path[0]);
 492 }
 493 #define offset_1st_component git_offset_1st_component
 494 #endif
 495
 496 #ifndef is_valid_path
 497 #define is_valid_path(path) 1
 498 #endif
 499
 500 #ifndef is_path_owned_by_current_user
 501
 502 #ifdef __TANDEM
 503 #define ROOT_UID 65535
 504 #else
 505 #define ROOT_UID 0
 506 #endif
 507
 508 /*
 509  * Do not use this function when
 510  * (1) geteuid() did not say we are running as 'root', or
 511  * (2) using this function will compromise the system.
 512  *
 513  * PORTABILITY WARNING:
 514  * This code assumes uid_t is unsigned because that is what sudo does.
 515  * If your uid_t type is signed and all your ids are positive then it
 516  * should all work fine.
 517  * If your version of sudo uses negative values for uid_t or it is
 518  * buggy and return an overflowed value in SUDO_UID, then git might
 519  * fail to grant access to your repository properly or even mistakenly
 520  * grant access to someone else.
 521  * In the unlikely scenario this happened to you, and that is how you
 522  * got to this message, we would like to know about it; so sent us an
 523  * email to git@vger.kernel.org indicating which platform you are
 524  * using and which version of sudo, so we can improve this logic and
 525  * maybe provide you with a patch that would prevent this issue again
 526  * in the future.
 527  */
 528 static inline void extract_id_from_env(const char *env, uid_t *id)
 529 {
 530         const char *real_uid = getenv(env);
 531
 532         /* discard anything empty to avoid a more complex check below */
 533         if (real_uid && *real_uid) {
 534                 char *endptr = NULL;
 535                 unsigned long env_id;
 536
 537                 errno = 0;
 538                 /* silent overflow errors could trigger a bug here */
 539                 env_id = strtoul(real_uid, &endptr, 10);
 540                 if (!*endptr && !errno)
 541                         *id = env_id;
 542         }
 543 }
 544
 545 static inline int is_path_owned_by_current_uid(const char *path,
 546                                                struct strbuf *report UNUSED)
 547 {
 548         struct stat st;
 549         uid_t euid;
 550
 551         if (lstat(path, &st))
 552                 return 0;
 553
 554         euid = geteuid();
 555         if (euid == ROOT_UID)
 556         {
 557                 if (st.st_uid == ROOT_UID)
 558                         return 1;
 559                 else
 560                         extract_id_from_env("SUDO_UID", &euid);
 561         }
 562
 563         return st.st_uid == euid;
 564 }
 565
 566 #define is_path_owned_by_current_user is_path_owned_by_current_uid
 567 #endif
 568
 569 #ifndef find_last_dir_sep
 570 static inline char *git_find_last_dir_sep(const char *path)
 571 {
 572         return strrchr(path, '/');
 573 }
 574 #define find_last_dir_sep git_find_last_dir_sep
 575 #endif
 576
 577 #ifndef has_dir_sep
 578 static inline int git_has_dir_sep(const char *path)
 579 {
 580         return !!strchr(path, '/');
 581 }
 582 #define has_dir_sep(path) git_has_dir_sep(path)
 583 #endif
 584
 585 #ifndef query_user_email
 586 #define query_user_email() NULL
 587 #endif
 588
 589 #ifdef __TANDEM
 590 #include <floss.h(floss_execl,floss_execlp,floss_execv,floss_execvp)>
 591 #include <floss.h(floss_getpwuid)>
 592 #ifndef NSIG
 593 /*
 594  * NonStop NSE and NSX do not provide NSIG. SIGGUARDIAN(99) is the highest
 595  * known, by detective work using kill -l as a list is all signals
 596  * instead of signal.h where it should be.
 597  */
 598 # define NSIG 100
 599 #endif
 600 #endif
 601
 602 #if defined(__HP_cc) && (__HP_cc >= 61000)
 603 #define NORETURN __attribute__((noreturn))
 604 #define NORETURN_PTR
 605 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 606 #define NORETURN __attribute__((__noreturn__))
 607 #define NORETURN_PTR __attribute__((__noreturn__))
 608 #elif defined(_MSC_VER)
 609 #define NORETURN __declspec(noreturn)
 610 #define NORETURN_PTR
 611 #else
 612 #define NORETURN
 613 #define NORETURN_PTR
 614 #ifndef __GNUC__
 615 #ifndef __attribute__
 616 #define __attribute__(x)
 617 #endif
 618 #endif
 619 #endif
 620
 621 /* The sentinel attribute is valid from gcc version 4.0 */
 622 #if defined(__GNUC__) && (__GNUC__ >= 4)
 623 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 624 /* warn_unused_result exists as of gcc 3.4.0, but be lazy and check 4.0 */
 625 #define RESULT_MUST_BE_USED __attribute__ ((warn_unused_result))
 626 #else
 627 #define LAST_ARG_MUST_BE_NULL
 628 #define RESULT_MUST_BE_USED
 629 #endif
 630
 631 #define MAYBE_UNUSED __attribute__((__unused__))
 632
 633 #include "compat/bswap.h"
 634
 635 #include "wrapper.h"
 636
 637 /* General helper functions */
 638 NORETURN void usage(const char *err);
 639 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 640 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 641 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 642 int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
 643 int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 644 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 645 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 646 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 647 void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 648
 649 #ifndef NO_OPENSSL
 650 #ifdef APPLE_COMMON_CRYPTO
 651 #include "compat/apple-common-crypto.h"
 652 #else
 653 #include <openssl/evp.h>
 654 #include <openssl/hmac.h>
 655 #endif /* APPLE_COMMON_CRYPTO */
 656 #include <openssl/x509v3.h>
 657 #endif /* NO_OPENSSL */
 658
 659 #ifdef HAVE_OPENSSL_CSPRNG
 660 #include <openssl/rand.h>
 661 #endif
 662
 663 /*
 664  * Let callers be aware of the constant return value; this can help
 665  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 666  * because other compilers may be confused by this.
 667  */
 668 #if defined(__GNUC__)
 669 static inline int const_error(void)
 670 {
 671         return -1;
 672 }
 673 #define error(...) (error(__VA_ARGS__), const_error())
 674 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 675 #endif
 676
 677 typedef void (*report_fn)(const char *, va_list params);
 678
 679 void set_die_routine(NORETURN_PTR report_fn routine);
 680 report_fn get_die_message_routine(void);
 681 void set_error_routine(report_fn routine);
 682 report_fn get_error_routine(void);
 683 void set_warn_routine(report_fn routine);
 684 report_fn get_warn_routine(void);
 685 void set_die_is_recursing_routine(int (*routine)(void));
 686
 687 /*
 688  * If the string "str" begins with the string found in "prefix", return true.
 689  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 690  * the string right after the prefix).
 691  *
 692  * Otherwise, return false and leave "out" untouched.
 693  *
 694  * Examples:
 695  *
 696  *   [extract branch name, fail if not a branch]
 697  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 698  *      return -1;
 699  *
 700  *   [skip prefix if present, otherwise use whole string]
 701  *   skip_prefix(name, "refs/heads/", &name);
 702  */
 703 static inline bool skip_prefix(const char *str, const char *prefix,
 704                                const char **out)
 705 {
 706         do {
 707                 if (!*prefix) {
 708                         *out = str;
 709                         return true;
 710                 }
 711         } while (*str++ == *prefix++);
 712         return false;
 713 }
 714
 715 /*
 716  * Like skip_prefix, but promises never to read past "len" bytes of the input
 717  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 718  */
 719 static inline bool skip_prefix_mem(const char *buf, size_t len,
 720                                    const char *prefix,
 721                                    const char **out, size_t *outlen)
 722 {
 723         size_t prefix_len = strlen(prefix);
 724         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 725                 *out = buf + prefix_len;
 726                 *outlen = len - prefix_len;
 727                 return true;
 728         }
 729         return false;
 730 }
 731
 732 /*
 733  * If buf ends with suffix, return true and subtract the length of the suffix
 734  * from *len. Otherwise, return false and leave *len untouched.
 735  */
 736 static inline bool strip_suffix_mem(const char *buf, size_t *len,
 737                                     const char *suffix)
 738 {
 739         size_t suflen = strlen(suffix);
 740         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 741                 return false;
 742         *len -= suflen;
 743         return true;
 744 }
 745
 746 /*
 747  * If str ends with suffix, return true and set *len to the size of the string
 748  * without the suffix. Otherwise, return false and set *len to the size of the
 749  * string.
 750  *
 751  * Note that we do _not_ NUL-terminate str to the new length.
 752  */
 753 static inline bool strip_suffix(const char *str, const char *suffix,
 754                                 size_t *len)
 755 {
 756         *len = strlen(str);
 757         return strip_suffix_mem(str, len, suffix);
 758 }
 759
 760 #define SWAP(a, b) do {                                         \
 761         void *_swap_a_ptr = &(a);                               \
 762         void *_swap_b_ptr = &(b);                               \
 763         unsigned char _swap_buffer[sizeof(a)];                  \
 764         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 765         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 766                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 767         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 768 } while (0)
 769
 770 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 771
 772 #ifndef PROT_READ
 773 #define PROT_READ 1
 774 #define PROT_WRITE 2
 775 #define MAP_PRIVATE 1
 776 #endif
 777
 778 #define mmap git_mmap
 779 #define munmap git_munmap
 780 void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 781 int git_munmap(void *start, size_t length);
 782
 783 #else /* NO_MMAP || USE_WIN32_MMAP */
 784
 785 #include <sys/mman.h>
 786
 787 #endif /* NO_MMAP || USE_WIN32_MMAP */
 788
 789 #ifdef NO_MMAP
 790
 791 /* This value must be multiple of (pagesize * 2) */
 792 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 793
 794 #else /* NO_MMAP */
 795
 796 /* This value must be multiple of (pagesize * 2) */
 797 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 798         (sizeof(void*) >= 8 \
 799                 ?  1 * 1024 * 1024 * 1024 \
 800                 : 32 * 1024 * 1024)
 801
 802 #endif /* NO_MMAP */
 803
 804 #ifndef MAP_FAILED
 805 #define MAP_FAILED ((void *)-1)
 806 #endif
 807
 808 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 809 #define on_disk_bytes(st) ((st).st_size)
 810 #else
 811 #define on_disk_bytes(st) ((st).st_blocks * 512)
 812 #endif
 813
 814 #ifdef NEEDS_MODE_TRANSLATION
 815 #undef S_IFMT
 816 #undef S_IFREG
 817 #undef S_IFDIR
 818 #undef S_IFLNK
 819 #undef S_IFBLK
 820 #undef S_IFCHR
 821 #undef S_IFIFO
 822 #undef S_IFSOCK
 823 #define S_IFMT   0170000
 824 #define S_IFREG  0100000
 825 #define S_IFDIR  0040000
 826 #define S_IFLNK  0120000
 827 #define S_IFBLK  0060000
 828 #define S_IFCHR  0020000
 829 #define S_IFIFO  0010000
 830 #define S_IFSOCK 0140000
 831 #ifdef stat
 832 #undef stat
 833 #endif
 834 #define stat(path, buf) git_stat(path, buf)
 835 int git_stat(const char *, struct stat *);
 836 #ifdef fstat
 837 #undef fstat
 838 #endif
 839 #define fstat(fd, buf) git_fstat(fd, buf)
 840 int git_fstat(int, struct stat *);
 841 #ifdef lstat
 842 #undef lstat
 843 #endif
 844 #define lstat(path, buf) git_lstat(path, buf)
 845 int git_lstat(const char *, struct stat *);
 846 #endif
 847
 848 #define DEFAULT_PACKED_GIT_LIMIT \
 849         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 850
 851 #ifdef NO_PREAD
 852 #define pread git_pread
 853 ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 854 #endif
 855
 856 #ifdef NO_SETENV
 857 #define setenv gitsetenv
 858 int gitsetenv(const char *, const char *, int);
 859 #endif
 860
 861 #ifdef NO_MKDTEMP
 862 #define mkdtemp gitmkdtemp
 863 char *gitmkdtemp(char *);
 864 #endif
 865
 866 #ifdef NO_UNSETENV
 867 #define unsetenv gitunsetenv
 868 int gitunsetenv(const char *);
 869 #endif
 870
 871 #ifdef NO_STRCASESTR
 872 #define strcasestr gitstrcasestr
 873 char *gitstrcasestr(const char *haystack, const char *needle);
 874 #endif
 875
 876 #ifdef NO_STRLCPY
 877 #define strlcpy gitstrlcpy
 878 size_t gitstrlcpy(char *, const char *, size_t);
 879 #endif
 880
 881 #ifdef NO_STRTOUMAX
 882 #define strtoumax gitstrtoumax
 883 uintmax_t gitstrtoumax(const char *, char **, int);
 884 #define strtoimax gitstrtoimax
 885 intmax_t gitstrtoimax(const char *, char **, int);
 886 #endif
 887
 888 #ifdef NO_HSTRERROR
 889 #define hstrerror githstrerror
 890 const char *githstrerror(int herror);
 891 #endif
 892
 893 #ifdef NO_MEMMEM
 894 #define memmem gitmemmem
 895 void *gitmemmem(const void *haystack, size_t haystacklen,
 896                 const void *needle, size_t needlelen);
 897 #endif
 898
 899 #ifdef OVERRIDE_STRDUP
 900 #ifdef strdup
 901 #undef strdup
 902 #endif
 903 #define strdup gitstrdup
 904 char *gitstrdup(const char *s);
 905 #endif
 906
 907 #ifdef NO_GETPAGESIZE
 908 #define getpagesize() sysconf(_SC_PAGESIZE)
 909 #endif
 910
 911 #ifndef O_CLOEXEC
 912 #define O_CLOEXEC 0
 913 #endif
 914
 915 #ifdef FREAD_READS_DIRECTORIES
 916 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 917 #  ifdef fopen
 918 #   undef fopen
 919 #  endif
 920 #  define fopen(a,b) git_fopen(a,b)
 921 # endif
 922 FILE *git_fopen(const char*, const char*);
 923 #endif
 924
 925 #ifdef SNPRINTF_RETURNS_BOGUS
 926 #ifdef snprintf
 927 #undef snprintf
 928 #endif
 929 #define snprintf git_snprintf
 930 int git_snprintf(char *str, size_t maxsize,
 931                  const char *format, ...);
 932 #ifdef vsnprintf
 933 #undef vsnprintf
 934 #endif
 935 #define vsnprintf git_vsnprintf
 936 int git_vsnprintf(char *str, size_t maxsize,
 937                   const char *format, va_list ap);
 938 #endif
 939
 940 #ifdef OPEN_RETURNS_EINTR
 941 #undef open
 942 #define open git_open_with_retry
 943 int git_open_with_retry(const char *path, int flag, ...);
 944 #endif
 945
 946 #ifdef __GLIBC_PREREQ
 947 #if __GLIBC_PREREQ(2, 1)
 948 #define HAVE_STRCHRNUL
 949 #endif
 950 #endif
 951
 952 #ifndef HAVE_STRCHRNUL
 953 #define strchrnul gitstrchrnul
 954 static inline char *gitstrchrnul(const char *s, int c)
 955 {
 956         while (*s && *s != c)
 957                 s++;
 958         return (char *)s;
 959 }
 960 #endif
 961
 962 #ifdef NO_INET_PTON
 963 int inet_pton(int af, const char *src, void *dst);
 964 #endif
 965
 966 #ifdef NO_INET_NTOP
 967 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 968 #endif
 969
 970 #ifdef NO_PTHREADS
 971 #define atexit git_atexit
 972 int git_atexit(void (*handler)(void));
 973 #endif
 974
 975 static inline size_t st_add(size_t a, size_t b)
 976 {
 977         if (unsigned_add_overflows(a, b))
 978                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 979                     (uintmax_t)a, (uintmax_t)b);
 980         return a + b;
 981 }
 982 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 983 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 984
 985 static inline size_t st_mult(size_t a, size_t b)
 986 {
 987         if (unsigned_mult_overflows(a, b))
 988                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 989                     (uintmax_t)a, (uintmax_t)b);
 990         return a * b;
 991 }
 992
 993 static inline size_t st_sub(size_t a, size_t b)
 994 {
 995         if (a < b)
 996                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 997                     (uintmax_t)a, (uintmax_t)b);
 998         return a - b;
 999 }
1000
1001 static inline size_t st_left_shift(size_t a, unsigned shift)
1002 {
1003         if (unsigned_left_shift_overflows(a, shift))
1004                 die("size_t overflow: %"PRIuMAX" << %u",
1005                     (uintmax_t)a, shift);
1006         return a << shift;
1007 }
1008
1009 static inline unsigned long cast_size_t_to_ulong(size_t a)
1010 {
1011         if (a != (unsigned long)a)
1012                 die("object too large to read on this platform: %"
1013                     PRIuMAX" is cut off to %lu",
1014                     (uintmax_t)a, (unsigned long)a);
1015         return (unsigned long)a;
1016 }
1017
1018 static inline uint32_t cast_size_t_to_uint32_t(size_t a)
1019 {
1020         if (a != (uint32_t)a)
1021                 die("object too large to read on this platform: %"
1022                     PRIuMAX" is cut off to %u",
1023                     (uintmax_t)a, (uint32_t)a);
1024         return (uint32_t)a;
1025 }
1026
1027 static inline int cast_size_t_to_int(size_t a)
1028 {
1029         if (a > INT_MAX)
1030                 die("number too large to represent as int on this platform: %"PRIuMAX,
1031                     (uintmax_t)a);
1032         return (int)a;
1033 }
1034
1035 /*
1036  * Limit size of IO chunks, because huge chunks only cause pain.  OS X
1037  * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in
1038  * the absence of bugs, large chunks can result in bad latencies when
1039  * you decide to kill the process.
1040  *
1041  * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX
1042  * that is smaller than that, clip it to SSIZE_MAX, as a call to
1043  * read(2) or write(2) larger than that is allowed to fail.  As the last
1044  * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value"
1045  * to override this, if the definition of SSIZE_MAX given by the platform
1046  * is broken.
1047  */
1048 #ifndef MAX_IO_SIZE
1049 # define MAX_IO_SIZE_DEFAULT (8*1024*1024)
1050 # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT)
1051 #  define MAX_IO_SIZE SSIZE_MAX
1052 # else
1053 #  define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT
1054 # endif
1055 #endif
1056
1057 #ifdef HAVE_ALLOCA_H
1058 # include <alloca.h>
1059 # define xalloca(size)      (alloca(size))
1060 # define xalloca_free(p)    do {} while (0)
1061 #else
1062 # define xalloca(size)      (xmalloc(size))
1063 # define xalloca_free(p)    (free(p))
1064 #endif
1065
1066 /*
1067  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
1068  * that ptr is used twice, so don't pass e.g. ptr++.
1069  */
1070 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
1071
1072 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
1073 #define CALLOC_ARRAY(x, alloc) (x) = xcalloc((alloc), sizeof(*(x)))
1074 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
1075
1076 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
1077         BARF_UNLESS_COPYABLE((dst), (src)))
1078 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
1079 {
1080         if (n)
1081                 memcpy(dst, src, st_mult(size, n));
1082 }
1083
1084 #define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
1085         BARF_UNLESS_COPYABLE((dst), (src)))
1086 static inline void move_array(void *dst, const void *src, size_t n, size_t size)
1087 {
1088         if (n)
1089                 memmove(dst, src, st_mult(size, n));
1090 }
1091
1092 #define DUP_ARRAY(dst, src, n) do { \
1093         size_t dup_array_n_ = (n); \
1094         COPY_ARRAY(ALLOC_ARRAY((dst), dup_array_n_), (src), dup_array_n_); \
1095 } while (0)
1096
1097 /*
1098  * These functions help you allocate structs with flex arrays, and copy
1099  * the data directly into the array. For example, if you had:
1100  *
1101  *   struct foo {
1102  *     int bar;
1103  *     char name[FLEX_ARRAY];
1104  *   };
1105  *
1106  * you can do:
1107  *
1108  *   struct foo *f;
1109  *   FLEX_ALLOC_MEM(f, name, src, len);
1110  *
1111  * to allocate a "foo" with the contents of "src" in the "name" field.
1112  * The resulting struct is automatically zero'd, and the flex-array field
1113  * is NUL-terminated (whether the incoming src buffer was or not).
1114  *
1115  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
1116  * but do want to store a pointer to some extra data in the same allocated
1117  * block. For example, if you have:
1118  *
1119  *   struct foo {
1120  *     char *name;
1121  *     int bar;
1122  *   };
1123  *
1124  * you can do:
1125  *
1126  *   struct foo *f;
1127  *   FLEXPTR_ALLOC_STR(f, name, src);
1128  *
1129  * and "name" will point to a block of memory after the struct, which will be
1130  * freed along with the struct (but the pointer can be repointed anywhere).
1131  *
1132  * The *_STR variants accept a string parameter rather than a ptr/len
1133  * combination.
1134  *
1135  * Note that these macros will evaluate the first parameter multiple
1136  * times, and it must be assignable as an lvalue.
1137  */
1138 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
1139         size_t flex_array_len_ = (len); \
1140         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1141         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
1142 } while (0)
1143 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
1144         size_t flex_array_len_ = (len); \
1145         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
1146         memcpy((x) + 1, (buf), flex_array_len_); \
1147         (x)->ptrname = (void *)((x)+1); \
1148 } while(0)
1149 #define FLEX_ALLOC_STR(x, flexname, str) \
1150         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
1151 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
1152         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
1153
1154 #define alloc_nr(x) (((x)+16)*3/2)
1155
1156 /**
1157  * Dynamically growing an array using realloc() is error prone and boring.
1158  *
1159  * Define your array with:
1160  *
1161  * - a pointer (`item`) that points at the array, initialized to `NULL`
1162  *   (although please name the variable based on its contents, not on its
1163  *   type);
1164  *
1165  * - an integer variable (`alloc`) that keeps track of how big the current
1166  *   allocation is, initialized to `0`;
1167  *
1168  * - another integer variable (`nr`) to keep track of how many elements the
1169  *   array currently has, initialized to `0`.
1170  *
1171  * Then before adding `n`th element to the item, call `ALLOC_GROW(item, n,
1172  * alloc)`.  This ensures that the array can hold at least `n` elements by
1173  * calling `realloc(3)` and adjusting `alloc` variable.
1174  *
1175  * ------------
1176  * sometype *item;
1177  * size_t nr;
1178  * size_t alloc
1179  *
1180  * for (i = 0; i < nr; i++)
1181  *      if (we like item[i] already)
1182  *              return;
1183  *
1184  * // we did not like any existing one, so add one
1185  * ALLOC_GROW(item, nr + 1, alloc);
1186  * item[nr++] = value you like;
1187  * ------------
1188  *
1189  * You are responsible for updating the `nr` variable.
1190  *
1191  * If you need to specify the number of elements to allocate explicitly
1192  * then use the macro `REALLOC_ARRAY(item, alloc)` instead of `ALLOC_GROW`.
1193  *
1194  * Consider using ALLOC_GROW_BY instead of ALLOC_GROW as it has some
1195  * added niceties.
1196  *
1197  * DO NOT USE any expression with side-effect for 'x', 'nr', or 'alloc'.
1198  */
1199 #define ALLOC_GROW(x, nr, alloc) \
1200         do { \
1201                 if ((nr) > alloc) { \
1202                         if (alloc_nr(alloc) < (nr)) \
1203                                 alloc = (nr); \
1204                         else \
1205                                 alloc = alloc_nr(alloc); \
1206                         REALLOC_ARRAY(x, alloc); \
1207                 } \
1208         } while (0)
1209
1210 /*
1211  * Similar to ALLOC_GROW but handles updating of the nr value and
1212  * zeroing the bytes of the newly-grown array elements.
1213  *
1214  * DO NOT USE any expression with side-effect for any of the
1215  * arguments.
1216  */
1217 #define ALLOC_GROW_BY(x, nr, increase, alloc) \
1218         do { \
1219                 if (increase) { \
1220                         size_t new_nr = nr + (increase); \
1221                         if (new_nr < nr) \
1222                                 BUG("negative growth in ALLOC_GROW_BY"); \
1223                         ALLOC_GROW(x, new_nr, alloc); \
1224                         memset((x) + nr, 0, sizeof(*(x)) * (increase)); \
1225                         nr = new_nr; \
1226                 } \
1227         } while (0)
1228
1229 static inline char *xstrdup_or_null(const char *str)
1230 {
1231         return str ? xstrdup(str) : NULL;
1232 }
1233
1234 static inline size_t xsize_t(off_t len)
1235 {
1236         if (len < 0 || (uintmax_t) len > SIZE_MAX)
1237                 die("Cannot handle files this big");
1238         return (size_t) len;
1239 }
1240
1241 #ifndef HOST_NAME_MAX
1242 #define HOST_NAME_MAX 256
1243 #endif
1244
1245 #include "sane-ctype.h"
1246
1247 /*
1248  * Like skip_prefix, but compare case-insensitively. Note that the comparison
1249  * is done via tolower(), so it is strictly ASCII (no multi-byte characters or
1250  * locale-specific conversions).
1251  */
1252 static inline int skip_iprefix(const char *str, const char *prefix,
1253                                const char **out)
1254 {
1255         do {
1256                 if (!*prefix) {
1257                         *out = str;
1258                         return 1;
1259                 }
1260         } while (tolower(*str++) == tolower(*prefix++));
1261         return 0;
1262 }
1263
1264 /*
1265  * Like skip_prefix_mem, but compare case-insensitively. Note that the
1266  * comparison is done via tolower(), so it is strictly ASCII (no multi-byte
1267  * characters or locale-specific conversions).
1268  */
1269 static inline int skip_iprefix_mem(const char *buf, size_t len,
1270                                    const char *prefix,
1271                                    const char **out, size_t *outlen)
1272 {
1273         do {
1274                 if (!*prefix) {
1275                         *out = buf;
1276                         *outlen = len;
1277                         return 1;
1278                 }
1279         } while (len-- > 0 && tolower(*buf++) == tolower(*prefix++));
1280         return 0;
1281 }
1282
1283 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
1284 {
1285         unsigned long ul;
1286         char *p;
1287
1288         errno = 0;
1289         /* negative values would be accepted by strtoul */
1290         if (strchr(s, '-'))
1291                 return -1;
1292         ul = strtoul(s, &p, base);
1293         if (errno || *p || p == s || (unsigned int) ul != ul)
1294                 return -1;
1295         *result = ul;
1296         return 0;
1297 }
1298
1299 static inline int strtol_i(char const *s, int base, int *result)
1300 {
1301         long ul;
1302         char *p;
1303
1304         errno = 0;
1305         ul = strtol(s, &p, base);
1306         if (errno || *p || p == s || (int) ul != ul)
1307                 return -1;
1308         *result = ul;
1309         return 0;
1310 }
1311
1312 void git_stable_qsort(void *base, size_t nmemb, size_t size,
1313                       int(*compar)(const void *, const void *));
1314 #ifdef INTERNAL_QSORT
1315 #define qsort git_stable_qsort
1316 #endif
1317
1318 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1319 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1320                               int(*compar)(const void *, const void *))
1321 {
1322         if (nmemb > 1)
1323                 qsort(base, nmemb, size, compar);
1324 }
1325
1326 #define STABLE_QSORT(base, n, compar) \
1327         git_stable_qsort((base), (n), sizeof(*(base)), compar)
1328
1329 #ifndef HAVE_ISO_QSORT_S
1330 int git_qsort_s(void *base, size_t nmemb, size_t size,
1331                 int (*compar)(const void *, const void *, void *), void *ctx);
1332 #define qsort_s git_qsort_s
1333 #endif
1334
1335 #define QSORT_S(base, n, compar, ctx) do {                      \
1336         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1337                 BUG("qsort_s() failed");                        \
1338 } while (0)
1339
1340 #ifndef REG_STARTEND
1341 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1342 #endif
1343
1344 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1345                               size_t nmatch, regmatch_t pmatch[], int eflags)
1346 {
1347         assert(nmatch > 0 && pmatch);
1348         pmatch[0].rm_so = 0;
1349         pmatch[0].rm_eo = size;
1350         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1351 }
1352
1353 #ifdef USE_ENHANCED_BASIC_REGULAR_EXPRESSIONS
1354 int git_regcomp(regex_t *preg, const char *pattern, int cflags);
1355 #define regcomp git_regcomp
1356 #endif
1357
1358 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1359 # define FORCE_DIR_SET_GID S_ISGID
1360 #else
1361 # define FORCE_DIR_SET_GID 0
1362 #endif
1363
1364 #ifdef NO_NSEC
1365 #undef USE_NSEC
1366 #define ST_CTIME_NSEC(st) 0
1367 #define ST_MTIME_NSEC(st) 0
1368 #else
1369 #ifdef USE_ST_TIMESPEC
1370 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1371 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1372 #else
1373 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1374 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1375 #endif
1376 #endif
1377
1378 #ifdef UNRELIABLE_FSTAT
1379 #define fstat_is_reliable() 0
1380 #else
1381 #define fstat_is_reliable() 1
1382 #endif
1383
1384 #ifndef va_copy
1385 /*
1386  * Since an obvious implementation of va_list would be to make it a
1387  * pointer into the stack frame, a simple assignment will work on
1388  * many systems.  But let's try to be more portable.
1389  */
1390 #ifdef __va_copy
1391 #define va_copy(dst, src) __va_copy(dst, src)
1392 #else
1393 #define va_copy(dst, src) ((dst) = (src))
1394 #endif
1395 #endif
1396
1397 /* usage.c: only to be used for testing BUG() implementation (see test-tool) */
1398 extern int BUG_exit_code;
1399
1400 /* usage.c: if bug() is called we should have a BUG_if_bug() afterwards */
1401 extern int bug_called_must_BUG;
1402
1403 __attribute__((format (printf, 3, 4))) NORETURN
1404 void BUG_fl(const char *file, int line, const char *fmt, ...);
1405 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1406 __attribute__((format (printf, 3, 4)))
1407 void bug_fl(const char *file, int line, const char *fmt, ...);
1408 #define bug(...) bug_fl(__FILE__, __LINE__, __VA_ARGS__)
1409 #define BUG_if_bug(...) do { \
1410         if (bug_called_must_BUG) \
1411                 BUG_fl(__FILE__, __LINE__, __VA_ARGS__); \
1412 } while (0)
1413
1414 #ifndef FSYNC_METHOD_DEFAULT
1415 #ifdef __APPLE__
1416 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_WRITEOUT_ONLY
1417 #else
1418 #define FSYNC_METHOD_DEFAULT FSYNC_METHOD_FSYNC
1419 #endif
1420 #endif
1421
1422 #ifndef SHELL_PATH
1423 # define SHELL_PATH "/bin/sh"
1424 #endif
1425
1426 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1427 static inline void git_flockfile(FILE *fh UNUSED)
1428 {
1429         ; /* nothing */
1430 }
1431 static inline void git_funlockfile(FILE *fh UNUSED)
1432 {
1433         ; /* nothing */
1434 }
1435 #undef flockfile
1436 #undef funlockfile
1437 #undef getc_unlocked
1438 #define flockfile(fh) git_flockfile(fh)
1439 #define funlockfile(fh) git_funlockfile(fh)
1440 #define getc_unlocked(fh) getc(fh)
1441 #endif
1442
1443 #ifdef FILENO_IS_A_MACRO
1444 int git_fileno(FILE *stream);
1445 # ifndef COMPAT_CODE_FILENO
1446 #  undef fileno
1447 #  define fileno(p) git_fileno(p)
1448 # endif
1449 #endif
1450
1451 #ifdef NEED_ACCESS_ROOT_HANDLER
1452 int git_access(const char *path, int mode);
1453 # ifndef COMPAT_CODE_ACCESS
1454 #  ifdef access
1455 #  undef access
1456 #  endif
1457 #  define access(path, mode) git_access(path, mode)
1458 # endif
1459 #endif
1460
1461 /*
1462  * Our code often opens a path to an optional file, to work on its
1463  * contents when we can successfully open it.  We can ignore a failure
1464  * to open if such an optional file does not exist, but we do want to
1465  * report a failure in opening for other reasons (e.g. we got an I/O
1466  * error, or the file is there, but we lack the permission to open).
1467  *
1468  * Call this function after seeing an error from open() or fopen() to
1469  * see if the errno indicates a missing file that we can safely ignore.
1470  */
1471 static inline int is_missing_file_error(int errno_)
1472 {
1473         return (errno_ == ENOENT || errno_ == ENOTDIR);
1474 }
1475
1476 int cmd_main(int, const char **);
1477
1478 /*
1479  * Intercept all calls to exit() and route them to trace2 to
1480  * optionally emit a message before calling the real exit().
1481  */
1482 int common_exit(const char *file, int line, int code);
1483 #define exit(code) exit(common_exit(__FILE__, __LINE__, (code)))
1484
1485 /*
1486  * You can mark a stack variable with UNLEAK(var) to avoid it being
1487  * reported as a leak by tools like LSAN or valgrind. The argument
1488  * should generally be the variable itself (not its address and not what
1489  * it points to). It's safe to use this on pointers which may already
1490  * have been freed, or on pointers which may still be in use.
1491  *
1492  * Use this _only_ for a variable that leaks by going out of scope at
1493  * program exit (so only from cmd_* functions or their direct helpers).
1494  * Normal functions, especially those which may be called multiple
1495  * times, should actually free their memory. This is only meant as
1496  * an annotation, and does nothing in non-leak-checking builds.
1497  */
1498 #ifdef SUPPRESS_ANNOTATED_LEAKS
1499 void unleak_memory(const void *ptr, size_t len);
1500 #define UNLEAK(var) unleak_memory(&(var), sizeof(var))
1501 #else
1502 #define UNLEAK(var) do {} while (0)
1503 #endif
1504
1505 #define z_const
1506 #include <zlib.h>
1507
1508 #if ZLIB_VERNUM < 0x1290
1509 /*
1510  * This is uncompress2, which is only available in zlib >= 1.2.9
1511  * (released as of early 2017). See compat/zlib-uncompress2.c.
1512  */
1513 int uncompress2(Bytef *dest, uLongf *destLen, const Bytef *source,
1514                 uLong *sourceLen);
1515 #endif
1516
1517 /*
1518  * This include must come after system headers, since it introduces macros that
1519  * replace system names.
1520  */
1521 #include "banned.h"
1522
1523 /*
1524  * container_of - Get the address of an object containing a field.
1525  *
1526  * @ptr: pointer to the field.
1527  * @type: type of the object.
1528  * @member: name of the field within the object.
1529  */
1530 #define container_of(ptr, type, member) \
1531         ((type *) ((char *)(ptr) - offsetof(type, member)))
1532
1533 /*
1534  * helper function for `container_of_or_null' to avoid multiple
1535  * evaluation of @ptr
1536  */
1537 static inline void *container_of_or_null_offset(void *ptr, size_t offset)
1538 {
1539         return ptr ? (char *)ptr - offset : NULL;
1540 }
1541
1542 /*
1543  * like `container_of', but allows returned value to be NULL
1544  */
1545 #define container_of_or_null(ptr, type, member) \
1546         (type *)container_of_or_null_offset(ptr, offsetof(type, member))
1547
1548 /*
1549  * like offsetof(), but takes a pointer to a variable of type which
1550  * contains @member, instead of a specified type.
1551  * @ptr is subject to multiple evaluation since we can't rely on __typeof__
1552  * everywhere.
1553  */
1554 #if defined(__GNUC__) /* clang sets this, too */
1555 #define OFFSETOF_VAR(ptr, member) offsetof(__typeof__(*ptr), member)
1556 #else /* !__GNUC__ */
1557 #define OFFSETOF_VAR(ptr, member) \
1558         ((uintptr_t)&(ptr)->member - (uintptr_t)(ptr))
1559 #endif /* !__GNUC__ */
1560
1561 #endif