git-compat-util.h

   1 #ifndef GIT_COMPAT_UTIL_H
   2 #define GIT_COMPAT_UTIL_H
   3
   4 #define _FILE_OFFSET_BITS 64
   5
   6
   7 /* Derived from Linux "Features Test Macro" header
   8  * Convenience macros to test the versions of gcc (or
   9  * a compatible compiler).
  10  * Use them like this:
  11  *  #if GIT_GNUC_PREREQ (2,8)
  12  *   ... code requiring gcc 2.8 or later ...
  13  *  #endif
  14 */
  15 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  16 # define GIT_GNUC_PREREQ(maj, min) \
  17         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  18 #else
  19  #define GIT_GNUC_PREREQ(maj, min) 0
  20 #endif
  21
  22
  23 #ifndef FLEX_ARRAY
  24 /*
  25  * See if our compiler is known to support flexible array members.
  26  */
  27 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && (!defined(__SUNPRO_C) || (__SUNPRO_C > 0x580))
  28 # define FLEX_ARRAY /* empty */
  29 #elif defined(__GNUC__)
  30 # if (__GNUC__ >= 3)
  31 #  define FLEX_ARRAY /* empty */
  32 # else
  33 #  define FLEX_ARRAY 0 /* older GNU extension */
  34 # endif
  35 #endif
  36
  37 /*
  38  * Otherwise, default to safer but a bit wasteful traditional style
  39  */
  40 #ifndef FLEX_ARRAY
  41 # define FLEX_ARRAY 1
  42 #endif
  43 #endif
  44
  45
  46 /*
  47  * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
  48  * @cond: the compile-time condition which must be true.
  49  *
  50  * Your compile will fail if the condition isn't true, or can't be evaluated
  51  * by the compiler.  This can be used in an expression: its value is "0".
  52  *
  53  * Example:
  54  *      #define foo_to_char(foo)                                        \
  55  *               ((char *)(foo)                                         \
  56  *                + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
  57  */
  58 #define BUILD_ASSERT_OR_ZERO(cond) \
  59         (sizeof(char [1 - 2*!(cond)]) - 1)
  60
  61 #if GIT_GNUC_PREREQ(3, 1)
  62  /* &arr[0] degrades to a pointer: a different type from an array */
  63 # define BARF_UNLESS_AN_ARRAY(arr)                                              \
  64         BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(__typeof__(arr), \
  65                                                            __typeof__(&(arr)[0])))
  66 #else
  67 # define BARF_UNLESS_AN_ARRAY(arr) 0
  68 #endif
  69 /*
  70  * ARRAY_SIZE - get the number of elements in a visible array
  71  *  <at> x: the array whose size you want.
  72  *
  73  * This does not work on pointers, or arrays declared as [], or
  74  * function parameters.  With correct compiler support, such usage
  75  * will cause a build error (see the build_assert_or_zero macro).
  76  */
  77 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]) + BARF_UNLESS_AN_ARRAY(x))
  78
  79 #define bitsizeof(x)  (CHAR_BIT * sizeof(x))
  80
  81 #define maximum_signed_value_of_type(a) \
  82     (INTMAX_MAX >> (bitsizeof(intmax_t) - bitsizeof(a)))
  83
  84 #define maximum_unsigned_value_of_type(a) \
  85     (UINTMAX_MAX >> (bitsizeof(uintmax_t) - bitsizeof(a)))
  86
  87 /*
  88  * Signed integer overflow is undefined in C, so here's a helper macro
  89  * to detect if the sum of two integers will overflow.
  90  *
  91  * Requires: a >= 0, typeof(a) equals typeof(b)
  92  */
  93 #define signed_add_overflows(a, b) \
  94     ((b) > maximum_signed_value_of_type(a) - (a))
  95
  96 #define unsigned_add_overflows(a, b) \
  97     ((b) > maximum_unsigned_value_of_type(a) - (a))
  98
  99 /*
 100  * Returns true if the multiplication of "a" and "b" will
 101  * overflow. The types of "a" and "b" must match and must be unsigned.
 102  * Note that this macro evaluates "a" twice!
 103  */
 104 #define unsigned_mult_overflows(a, b) \
 105     ((a) && (b) > maximum_unsigned_value_of_type(a) / (a))
 106
 107 #ifdef __GNUC__
 108 #define TYPEOF(x) (__typeof__(x))
 109 #else
 110 #define TYPEOF(x)
 111 #endif
 112
 113 #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 114 #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 115
 116 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 117
 118 /* Approximation of the length of the decimal representation of this type. */
 119 #define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 120
 121 #if defined(__sun__)
 122  /*
 123   * On Solaris, when _XOPEN_EXTENDED is set, its header file
 124   * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 125   * setting to say we are XPG5 or XPG6.  Also on Solaris,
 126   * XPG6 programs must be compiled with a c99 compiler, while
 127   * non XPG6 programs must be compiled with a pre-c99 compiler.
 128   */
 129 # if __STDC_VERSION__ - 0 >= 199901L
 130 # define _XOPEN_SOURCE 600
 131 # else
 132 # define _XOPEN_SOURCE 500
 133 # endif
 134 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 135       !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 136       !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__) && \
 137       !defined(__CYGWIN__)
 138 #define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 139 #define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 140 #endif
 141 #define _ALL_SOURCE 1
 142 #define _GNU_SOURCE 1
 143 #define _BSD_SOURCE 1
 144 #define _DEFAULT_SOURCE 1
 145 #define _NETBSD_SOURCE 1
 146 #define _SGI_SOURCE 1
 147
 148 #if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 149 # if defined (_MSC_VER) && !defined(_WIN32_WINNT)
 150 #  define _WIN32_WINNT 0x0502
 151 # endif
 152 #define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 153 #include <winsock2.h>
 154 #include <windows.h>
 155 #define GIT_WINDOWS_NATIVE
 156 #endif
 157
 158 #include <unistd.h>
 159 #include <stdio.h>
 160 #include <sys/stat.h>
 161 #include <fcntl.h>
 162 #include <stddef.h>
 163 #include <stdlib.h>
 164 #include <stdarg.h>
 165 #include <string.h>
 166 #ifdef HAVE_STRINGS_H
 167 #include <strings.h> /* for strcasecmp() */
 168 #endif
 169 #include <errno.h>
 170 #include <limits.h>
 171 #ifdef NEEDS_SYS_PARAM_H
 172 #include <sys/param.h>
 173 #endif
 174 #include <sys/types.h>
 175 #include <dirent.h>
 176 #include <sys/time.h>
 177 #include <time.h>
 178 #include <signal.h>
 179 #include <assert.h>
 180 #include <regex.h>
 181 #include <utime.h>
 182 #include <syslog.h>
 183 #ifndef NO_SYS_POLL_H
 184 #include <sys/poll.h>
 185 #else
 186 #include <poll.h>
 187 #endif
 188 #ifdef HAVE_BSD_SYSCTL
 189 #include <sys/sysctl.h>
 190 #endif
 191
 192 #if defined(__MINGW32__)
 193 /* pull in Windows compatibility stuff */
 194 #include "compat/mingw.h"
 195 #elif defined(_MSC_VER)
 196 #include "compat/msvc.h"
 197 #else
 198 #include <sys/utsname.h>
 199 #include <sys/wait.h>
 200 #include <sys/resource.h>
 201 #include <sys/socket.h>
 202 #include <sys/ioctl.h>
 203 #include <termios.h>
 204 #ifndef NO_SYS_SELECT_H
 205 #include <sys/select.h>
 206 #endif
 207 #include <netinet/in.h>
 208 #include <netinet/tcp.h>
 209 #include <arpa/inet.h>
 210 #include <netdb.h>
 211 #include <pwd.h>
 212 #include <sys/un.h>
 213 #ifndef NO_INTTYPES_H
 214 #include <inttypes.h>
 215 #else
 216 #include <stdint.h>
 217 #endif
 218 #ifdef NO_INTPTR_T
 219 /*
 220  * On I16LP32, ILP32 and LP64 "long" is the save bet, however
 221  * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 222  * while on IP16 and IP16L32 it is "int" (resp. "short")
 223  * Size needs to match (or exceed) 'sizeof(void *)'.
 224  * We can't take "long long" here as not everybody has it.
 225  */
 226 typedef long intptr_t;
 227 typedef unsigned long uintptr_t;
 228 #endif
 229 #undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 230 #include <grp.h>
 231 #define _ALL_SOURCE 1
 232 #endif
 233
 234 /* used on Mac OS X */
 235 #ifdef PRECOMPOSE_UNICODE
 236 #include "compat/precompose_utf8.h"
 237 #else
 238 #define precompose_str(in,i_nfd2nfc)
 239 #define precompose_argv(c,v)
 240 #define probe_utf8_pathname_composition()
 241 #endif
 242
 243 #ifdef MKDIR_WO_TRAILING_SLASH
 244 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 245 extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 246 #endif
 247
 248 #ifdef NO_STRUCT_ITIMERVAL
 249 struct itimerval {
 250         struct timeval it_interval;
 251         struct timeval it_value;
 252 };
 253 #endif
 254
 255 #ifdef NO_SETITIMER
 256 #define setitimer(which,value,ovalue)
 257 #endif
 258
 259 #ifndef NO_LIBGEN_H
 260 #include <libgen.h>
 261 #else
 262 #define basename gitbasename
 263 extern char *gitbasename(char *);
 264 #define dirname gitdirname
 265 extern char *gitdirname(char *);
 266 #endif
 267
 268 #ifndef NO_ICONV
 269 #include <iconv.h>
 270 #endif
 271
 272 #ifndef NO_OPENSSL
 273 #ifdef __APPLE__
 274 #define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 275 #include <AvailabilityMacros.h>
 276 #undef DEPRECATED_ATTRIBUTE
 277 #define DEPRECATED_ATTRIBUTE
 278 #undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 279 #endif
 280 #include <openssl/ssl.h>
 281 #include <openssl/err.h>
 282 #endif
 283
 284 /* On most systems <netdb.h> would have given us this, but
 285  * not on some systems (e.g. z/OS).
 286  */
 287 #ifndef NI_MAXHOST
 288 #define NI_MAXHOST 1025
 289 #endif
 290
 291 #ifndef NI_MAXSERV
 292 #define NI_MAXSERV 32
 293 #endif
 294
 295 /* On most systems <limits.h> would have given us this, but
 296  * not on some systems (e.g. GNU/Hurd).
 297  */
 298 #ifndef PATH_MAX
 299 #define PATH_MAX 4096
 300 #endif
 301
 302 #ifndef PRIuMAX
 303 #define PRIuMAX "llu"
 304 #endif
 305
 306 #ifndef SCNuMAX
 307 #define SCNuMAX PRIuMAX
 308 #endif
 309
 310 #ifndef PRIu32
 311 #define PRIu32 "u"
 312 #endif
 313
 314 #ifndef PRIx32
 315 #define PRIx32 "x"
 316 #endif
 317
 318 #ifndef PRIo32
 319 #define PRIo32 "o"
 320 #endif
 321
 322 typedef uintmax_t timestamp_t;
 323 #define PRItime PRIuMAX
 324 #define parse_timestamp strtoumax
 325 #define TIME_MAX UINTMAX_MAX
 326
 327 #ifndef PATH_SEP
 328 #define PATH_SEP ':'
 329 #endif
 330
 331 #ifdef HAVE_PATHS_H
 332 #include <paths.h>
 333 #endif
 334 #ifndef _PATH_DEFPATH
 335 #define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 336 #endif
 337
 338 #ifndef has_dos_drive_prefix
 339 static inline int git_has_dos_drive_prefix(const char *path)
 340 {
 341         return 0;
 342 }
 343 #define has_dos_drive_prefix git_has_dos_drive_prefix
 344 #endif
 345
 346 #ifndef skip_dos_drive_prefix
 347 static inline int git_skip_dos_drive_prefix(char **path)
 348 {
 349         return 0;
 350 }
 351 #define skip_dos_drive_prefix git_skip_dos_drive_prefix
 352 #endif
 353
 354 #ifndef is_dir_sep
 355 static inline int git_is_dir_sep(int c)
 356 {
 357         return c == '/';
 358 }
 359 #define is_dir_sep git_is_dir_sep
 360 #endif
 361
 362 #ifndef offset_1st_component
 363 static inline int git_offset_1st_component(const char *path)
 364 {
 365         return is_dir_sep(path[0]);
 366 }
 367 #define offset_1st_component git_offset_1st_component
 368 #endif
 369
 370 #ifndef find_last_dir_sep
 371 static inline char *git_find_last_dir_sep(const char *path)
 372 {
 373         return strrchr(path, '/');
 374 }
 375 #define find_last_dir_sep git_find_last_dir_sep
 376 #endif
 377
 378 #if defined(__HP_cc) && (__HP_cc >= 61000)
 379 #define NORETURN __attribute__((noreturn))
 380 #define NORETURN_PTR
 381 #elif defined(__GNUC__) && !defined(NO_NORETURN)
 382 #define NORETURN __attribute__((__noreturn__))
 383 #define NORETURN_PTR __attribute__((__noreturn__))
 384 #elif defined(_MSC_VER)
 385 #define NORETURN __declspec(noreturn)
 386 #define NORETURN_PTR
 387 #else
 388 #define NORETURN
 389 #define NORETURN_PTR
 390 #ifndef __GNUC__
 391 #ifndef __attribute__
 392 #define __attribute__(x)
 393 #endif
 394 #endif
 395 #endif
 396
 397 /* The sentinel attribute is valid from gcc version 4.0 */
 398 #if defined(__GNUC__) && (__GNUC__ >= 4)
 399 #define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 400 #else
 401 #define LAST_ARG_MUST_BE_NULL
 402 #endif
 403
 404 #include "compat/bswap.h"
 405
 406 #include "wildmatch.h"
 407
 408 struct strbuf;
 409
 410 /* General helper functions */
 411 extern void vreportf(const char *prefix, const char *err, va_list params);
 412 extern NORETURN void usage(const char *err);
 413 extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 414 extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 415 extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 416 extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 417 extern int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 418 extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 419 extern void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 420
 421 #ifndef NO_OPENSSL
 422 #ifdef APPLE_COMMON_CRYPTO
 423 #include "compat/apple-common-crypto.h"
 424 #else
 425 #include <openssl/evp.h>
 426 #include <openssl/hmac.h>
 427 #endif /* APPLE_COMMON_CRYPTO */
 428 #include <openssl/x509v3.h>
 429 #endif /* NO_OPENSSL */
 430
 431 /*
 432  * Let callers be aware of the constant return value; this can help
 433  * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 434  * because some compilers may not support variadic macros. Since we're only
 435  * trying to help gcc, anyway, it's OK; other compilers will fall back to
 436  * using the function as usual.
 437  */
 438 #if defined(__GNUC__)
 439 static inline int const_error(void)
 440 {
 441         return -1;
 442 }
 443 #define error(...) (error(__VA_ARGS__), const_error())
 444 #define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 445 #endif
 446
 447 extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 448 extern void set_error_routine(void (*routine)(const char *err, va_list params));
 449 extern void (*get_error_routine(void))(const char *err, va_list params);
 450 extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
 451 extern void (*get_warn_routine(void))(const char *warn, va_list params);
 452 extern void set_die_is_recursing_routine(int (*routine)(void));
 453
 454 extern int starts_with(const char *str, const char *prefix);
 455
 456 /*
 457  * If the string "str" begins with the string found in "prefix", return 1.
 458  * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 459  * the string right after the prefix).
 460  *
 461  * Otherwise, return 0 and leave "out" untouched.
 462  *
 463  * Examples:
 464  *
 465  *   [extract branch name, fail if not a branch]
 466  *   if (!skip_prefix(ref, "refs/heads/", &branch)
 467  *      return -1;
 468  *
 469  *   [skip prefix if present, otherwise use whole string]
 470  *   skip_prefix(name, "refs/heads/", &name);
 471  */
 472 static inline int skip_prefix(const char *str, const char *prefix,
 473                               const char **out)
 474 {
 475         do {
 476                 if (!*prefix) {
 477                         *out = str;
 478                         return 1;
 479                 }
 480         } while (*str++ == *prefix++);
 481         return 0;
 482 }
 483
 484 /*
 485  * Like skip_prefix, but promises never to read past "len" bytes of the input
 486  * buffer, and returns the remaining number of bytes in "out" via "outlen".
 487  */
 488 static inline int skip_prefix_mem(const char *buf, size_t len,
 489                                   const char *prefix,
 490                                   const char **out, size_t *outlen)
 491 {
 492         size_t prefix_len = strlen(prefix);
 493         if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 494                 *out = buf + prefix_len;
 495                 *outlen = len - prefix_len;
 496                 return 1;
 497         }
 498         return 0;
 499 }
 500
 501 /*
 502  * If buf ends with suffix, return 1 and subtract the length of the suffix
 503  * from *len. Otherwise, return 0 and leave *len untouched.
 504  */
 505 static inline int strip_suffix_mem(const char *buf, size_t *len,
 506                                    const char *suffix)
 507 {
 508         size_t suflen = strlen(suffix);
 509         if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 510                 return 0;
 511         *len -= suflen;
 512         return 1;
 513 }
 514
 515 /*
 516  * If str ends with suffix, return 1 and set *len to the size of the string
 517  * without the suffix. Otherwise, return 0 and set *len to the size of the
 518  * string.
 519  *
 520  * Note that we do _not_ NUL-terminate str to the new length.
 521  */
 522 static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 523 {
 524         *len = strlen(str);
 525         return strip_suffix_mem(str, len, suffix);
 526 }
 527
 528 static inline int ends_with(const char *str, const char *suffix)
 529 {
 530         size_t len;
 531         return strip_suffix(str, suffix, &len);
 532 }
 533
 534 #define SWAP(a, b) do {                                         \
 535         void *_swap_a_ptr = &(a);                               \
 536         void *_swap_b_ptr = &(b);                               \
 537         unsigned char _swap_buffer[sizeof(a)];                  \
 538         memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 539         memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 540                BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 541         memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 542 } while (0)
 543
 544 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 545
 546 #ifndef PROT_READ
 547 #define PROT_READ 1
 548 #define PROT_WRITE 2
 549 #define MAP_PRIVATE 1
 550 #endif
 551
 552 #define mmap git_mmap
 553 #define munmap git_munmap
 554 extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 555 extern int git_munmap(void *start, size_t length);
 556
 557 #else /* NO_MMAP || USE_WIN32_MMAP */
 558
 559 #include <sys/mman.h>
 560
 561 #endif /* NO_MMAP || USE_WIN32_MMAP */
 562
 563 #ifdef NO_MMAP
 564
 565 /* This value must be multiple of (pagesize * 2) */
 566 #define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 567
 568 #else /* NO_MMAP */
 569
 570 /* This value must be multiple of (pagesize * 2) */
 571 #define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 572         (sizeof(void*) >= 8 \
 573                 ?  1 * 1024 * 1024 * 1024 \
 574                 : 32 * 1024 * 1024)
 575
 576 #endif /* NO_MMAP */
 577
 578 #ifndef MAP_FAILED
 579 #define MAP_FAILED ((void *)-1)
 580 #endif
 581
 582 #ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 583 #define on_disk_bytes(st) ((st).st_size)
 584 #else
 585 #define on_disk_bytes(st) ((st).st_blocks * 512)
 586 #endif
 587
 588 #ifdef NEEDS_MODE_TRANSLATION
 589 #undef S_IFMT
 590 #undef S_IFREG
 591 #undef S_IFDIR
 592 #undef S_IFLNK
 593 #undef S_IFBLK
 594 #undef S_IFCHR
 595 #undef S_IFIFO
 596 #undef S_IFSOCK
 597 #define S_IFMT   0170000
 598 #define S_IFREG  0100000
 599 #define S_IFDIR  0040000
 600 #define S_IFLNK  0120000
 601 #define S_IFBLK  0060000
 602 #define S_IFCHR  0020000
 603 #define S_IFIFO  0010000
 604 #define S_IFSOCK 0140000
 605 #ifdef stat
 606 #undef stat
 607 #endif
 608 #define stat(path, buf) git_stat(path, buf)
 609 extern int git_stat(const char *, struct stat *);
 610 #ifdef fstat
 611 #undef fstat
 612 #endif
 613 #define fstat(fd, buf) git_fstat(fd, buf)
 614 extern int git_fstat(int, struct stat *);
 615 #ifdef lstat
 616 #undef lstat
 617 #endif
 618 #define lstat(path, buf) git_lstat(path, buf)
 619 extern int git_lstat(const char *, struct stat *);
 620 #endif
 621
 622 #define DEFAULT_PACKED_GIT_LIMIT \
 623         ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 624
 625 #ifdef NO_PREAD
 626 #define pread git_pread
 627 extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 628 #endif
 629 /*
 630  * Forward decl that will remind us if its twin in cache.h changes.
 631  * This function is used in compat/pread.c.  But we can't include
 632  * cache.h there.
 633  */
 634 extern ssize_t read_in_full(int fd, void *buf, size_t count);
 635
 636 #ifdef NO_SETENV
 637 #define setenv gitsetenv
 638 extern int gitsetenv(const char *, const char *, int);
 639 #endif
 640
 641 #ifdef NO_MKDTEMP
 642 #define mkdtemp gitmkdtemp
 643 extern char *gitmkdtemp(char *);
 644 #endif
 645
 646 #ifdef NO_UNSETENV
 647 #define unsetenv gitunsetenv
 648 extern void gitunsetenv(const char *);
 649 #endif
 650
 651 #ifdef NO_STRCASESTR
 652 #define strcasestr gitstrcasestr
 653 extern char *gitstrcasestr(const char *haystack, const char *needle);
 654 #endif
 655
 656 #ifdef NO_STRLCPY
 657 #define strlcpy gitstrlcpy
 658 extern size_t gitstrlcpy(char *, const char *, size_t);
 659 #endif
 660
 661 #ifdef NO_STRTOUMAX
 662 #define strtoumax gitstrtoumax
 663 extern uintmax_t gitstrtoumax(const char *, char **, int);
 664 #define strtoimax gitstrtoimax
 665 extern intmax_t gitstrtoimax(const char *, char **, int);
 666 #endif
 667
 668 #ifdef NO_HSTRERROR
 669 #define hstrerror githstrerror
 670 extern const char *githstrerror(int herror);
 671 #endif
 672
 673 #ifdef NO_MEMMEM
 674 #define memmem gitmemmem
 675 void *gitmemmem(const void *haystack, size_t haystacklen,
 676                 const void *needle, size_t needlelen);
 677 #endif
 678
 679 #ifdef OVERRIDE_STRDUP
 680 #ifdef strdup
 681 #undef strdup
 682 #endif
 683 #define strdup gitstrdup
 684 char *gitstrdup(const char *s);
 685 #endif
 686
 687 #ifdef NO_GETPAGESIZE
 688 #define getpagesize() sysconf(_SC_PAGESIZE)
 689 #endif
 690
 691 #ifndef O_CLOEXEC
 692 #define O_CLOEXEC 0
 693 #endif
 694
 695 #ifdef FREAD_READS_DIRECTORIES
 696 # if !defined(SUPPRESS_FOPEN_REDEFINITION)
 697 #  ifdef fopen
 698 #   undef fopen
 699 #  endif
 700 #  define fopen(a,b) git_fopen(a,b)
 701 # endif
 702 extern FILE *git_fopen(const char*, const char*);
 703 #endif
 704
 705 #ifdef SNPRINTF_RETURNS_BOGUS
 706 #ifdef snprintf
 707 #undef snprintf
 708 #endif
 709 #define snprintf git_snprintf
 710 extern int git_snprintf(char *str, size_t maxsize,
 711                         const char *format, ...);
 712 #ifdef vsnprintf
 713 #undef vsnprintf
 714 #endif
 715 #define vsnprintf git_vsnprintf
 716 extern int git_vsnprintf(char *str, size_t maxsize,
 717                          const char *format, va_list ap);
 718 #endif
 719
 720 #ifdef __GLIBC_PREREQ
 721 #if __GLIBC_PREREQ(2, 1)
 722 #define HAVE_STRCHRNUL
 723 #endif
 724 #endif
 725
 726 #ifndef HAVE_STRCHRNUL
 727 #define strchrnul gitstrchrnul
 728 static inline char *gitstrchrnul(const char *s, int c)
 729 {
 730         while (*s && *s != c)
 731                 s++;
 732         return (char *)s;
 733 }
 734 #endif
 735
 736 #ifdef NO_INET_PTON
 737 int inet_pton(int af, const char *src, void *dst);
 738 #endif
 739
 740 #ifdef NO_INET_NTOP
 741 const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 742 #endif
 743
 744 #ifdef NO_PTHREADS
 745 #define atexit git_atexit
 746 extern int git_atexit(void (*handler)(void));
 747 #endif
 748
 749 extern void release_pack_memory(size_t);
 750
 751 typedef void (*try_to_free_t)(size_t);
 752 extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 753
 754 static inline size_t st_add(size_t a, size_t b)
 755 {
 756         if (unsigned_add_overflows(a, b))
 757                 die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 758                     (uintmax_t)a, (uintmax_t)b);
 759         return a + b;
 760 }
 761 #define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 762 #define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 763
 764 static inline size_t st_mult(size_t a, size_t b)
 765 {
 766         if (unsigned_mult_overflows(a, b))
 767                 die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 768                     (uintmax_t)a, (uintmax_t)b);
 769         return a * b;
 770 }
 771
 772 static inline size_t st_sub(size_t a, size_t b)
 773 {
 774         if (a < b)
 775                 die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 776                     (uintmax_t)a, (uintmax_t)b);
 777         return a - b;
 778 }
 779
 780 #ifdef HAVE_ALLOCA_H
 781 # include <alloca.h>
 782 # define xalloca(size)      (alloca(size))
 783 # define xalloca_free(p)    do {} while (0)
 784 #else
 785 # define xalloca(size)      (xmalloc(size))
 786 # define xalloca_free(p)    (free(p))
 787 #endif
 788 extern char *xstrdup(const char *str);
 789 extern void *xmalloc(size_t size);
 790 extern void *xmallocz(size_t size);
 791 extern void *xmallocz_gently(size_t size);
 792 extern void *xmemdupz(const void *data, size_t len);
 793 extern char *xstrndup(const char *str, size_t len);
 794 extern void *xrealloc(void *ptr, size_t size);
 795 extern void *xcalloc(size_t nmemb, size_t size);
 796 extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 797 extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 798 extern int xopen(const char *path, int flags, ...);
 799 extern ssize_t xread(int fd, void *buf, size_t len);
 800 extern ssize_t xwrite(int fd, const void *buf, size_t len);
 801 extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 802 extern int xdup(int fd);
 803 extern FILE *xfopen(const char *path, const char *mode);
 804 extern FILE *xfdopen(int fd, const char *mode);
 805 extern int xmkstemp(char *template);
 806 extern int xmkstemp_mode(char *template, int mode);
 807 extern char *xgetcwd(void);
 808 extern FILE *fopen_for_writing(const char *path);
 809 extern FILE *fopen_or_warn(const char *path, const char *mode);
 810
 811 /*
 812  * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 813  * that ptr is used twice, so don't pass e.g. ptr++.
 814  */
 815 #define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 816
 817 #define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 818 #define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 819
 820 #define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 821         BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 822 static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 823 {
 824         if (n)
 825                 memcpy(dst, src, st_mult(size, n));
 826 }
 827
 828 /*
 829  * These functions help you allocate structs with flex arrays, and copy
 830  * the data directly into the array. For example, if you had:
 831  *
 832  *   struct foo {
 833  *     int bar;
 834  *     char name[FLEX_ARRAY];
 835  *   };
 836  *
 837  * you can do:
 838  *
 839  *   struct foo *f;
 840  *   FLEX_ALLOC_MEM(f, name, src, len);
 841  *
 842  * to allocate a "foo" with the contents of "src" in the "name" field.
 843  * The resulting struct is automatically zero'd, and the flex-array field
 844  * is NUL-terminated (whether the incoming src buffer was or not).
 845  *
 846  * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
 847  * but do want to store a pointer to some extra data in the same allocated
 848  * block. For example, if you have:
 849  *
 850  *   struct foo {
 851  *     char *name;
 852  *     int bar;
 853  *   };
 854  *
 855  * you can do:
 856  *
 857  *   struct foo *f;
 858  *   FLEXPTR_ALLOC_STR(f, name, src);
 859  *
 860  * and "name" will point to a block of memory after the struct, which will be
 861  * freed along with the struct (but the pointer can be repointed anywhere).
 862  *
 863  * The *_STR variants accept a string parameter rather than a ptr/len
 864  * combination.
 865  *
 866  * Note that these macros will evaluate the first parameter multiple
 867  * times, and it must be assignable as an lvalue.
 868  */
 869 #define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
 870         size_t flex_array_len_ = (len); \
 871         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 872         memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
 873 } while (0)
 874 #define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
 875         size_t flex_array_len_ = (len); \
 876         (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 877         memcpy((x) + 1, (buf), flex_array_len_); \
 878         (x)->ptrname = (void *)((x)+1); \
 879 } while(0)
 880 #define FLEX_ALLOC_STR(x, flexname, str) \
 881         FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
 882 #define FLEXPTR_ALLOC_STR(x, ptrname, str) \
 883         FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
 884
 885 static inline char *xstrdup_or_null(const char *str)
 886 {
 887         return str ? xstrdup(str) : NULL;
 888 }
 889
 890 static inline size_t xsize_t(off_t len)
 891 {
 892         if (len > (size_t) len)
 893                 die("Cannot handle files this big");
 894         return (size_t)len;
 895 }
 896
 897 __attribute__((format (printf, 3, 4)))
 898 extern int xsnprintf(char *dst, size_t max, const char *fmt, ...);
 899
 900 #ifndef HOST_NAME_MAX
 901 #define HOST_NAME_MAX 256
 902 #endif
 903
 904 extern int xgethostname(char *buf, size_t len);
 905
 906 /* in ctype.c, for kwset users */
 907 extern const unsigned char tolower_trans_tbl[256];
 908
 909 /* Sane ctype - no locale, and works with signed chars */
 910 #undef isascii
 911 #undef isspace
 912 #undef isdigit
 913 #undef isalpha
 914 #undef isalnum
 915 #undef isprint
 916 #undef islower
 917 #undef isupper
 918 #undef tolower
 919 #undef toupper
 920 #undef iscntrl
 921 #undef ispunct
 922 #undef isxdigit
 923
 924 extern const unsigned char sane_ctype[256];
 925 #define GIT_SPACE 0x01
 926 #define GIT_DIGIT 0x02
 927 #define GIT_ALPHA 0x04
 928 #define GIT_GLOB_SPECIAL 0x08
 929 #define GIT_REGEX_SPECIAL 0x10
 930 #define GIT_PATHSPEC_MAGIC 0x20
 931 #define GIT_CNTRL 0x40
 932 #define GIT_PUNCT 0x80
 933 #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 934 #define isascii(x) (((x) & ~0x7f) == 0)
 935 #define isspace(x) sane_istest(x,GIT_SPACE)
 936 #define isdigit(x) sane_istest(x,GIT_DIGIT)
 937 #define isalpha(x) sane_istest(x,GIT_ALPHA)
 938 #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 939 #define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 940 #define islower(x) sane_iscase(x, 1)
 941 #define isupper(x) sane_iscase(x, 0)
 942 #define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 943 #define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 944 #define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 945 #define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 946                 GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 947 #define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 948 #define tolower(x) sane_case((unsigned char)(x), 0x20)
 949 #define toupper(x) sane_case((unsigned char)(x), 0)
 950 #define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 951
 952 static inline int sane_case(int x, int high)
 953 {
 954         if (sane_istest(x, GIT_ALPHA))
 955                 x = (x & ~0x20) | high;
 956         return x;
 957 }
 958
 959 static inline int sane_iscase(int x, int is_lower)
 960 {
 961         if (!sane_istest(x, GIT_ALPHA))
 962                 return 0;
 963
 964         if (is_lower)
 965                 return (x & 0x20) != 0;
 966         else
 967                 return (x & 0x20) == 0;
 968 }
 969
 970 static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 971 {
 972         unsigned long ul;
 973         char *p;
 974
 975         errno = 0;
 976         /* negative values would be accepted by strtoul */
 977         if (strchr(s, '-'))
 978                 return -1;
 979         ul = strtoul(s, &p, base);
 980         if (errno || *p || p == s || (unsigned int) ul != ul)
 981                 return -1;
 982         *result = ul;
 983         return 0;
 984 }
 985
 986 static inline int strtol_i(char const *s, int base, int *result)
 987 {
 988         long ul;
 989         char *p;
 990
 991         errno = 0;
 992         ul = strtol(s, &p, base);
 993         if (errno || *p || p == s || (int) ul != ul)
 994                 return -1;
 995         *result = ul;
 996         return 0;
 997 }
 998
 999 #ifdef INTERNAL_QSORT
1000 void git_qsort(void *base, size_t nmemb, size_t size,
1001                int(*compar)(const void *, const void *));
1002 #define qsort git_qsort
1003 #endif
1004
1005 #define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1006 static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1007                               int(*compar)(const void *, const void *))
1008 {
1009         if (nmemb > 1)
1010                 qsort(base, nmemb, size, compar);
1011 }
1012
1013 #ifndef HAVE_ISO_QSORT_S
1014 int git_qsort_s(void *base, size_t nmemb, size_t size,
1015                 int (*compar)(const void *, const void *, void *), void *ctx);
1016 #define qsort_s git_qsort_s
1017 #endif
1018
1019 #define QSORT_S(base, n, compar, ctx) do {                      \
1020         if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1021                 die("BUG: qsort_s() failed");                   \
1022 } while (0)
1023
1024 #ifndef REG_STARTEND
1025 #error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1026 #endif
1027
1028 static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1029                               size_t nmatch, regmatch_t pmatch[], int eflags)
1030 {
1031         assert(nmatch > 0 && pmatch);
1032         pmatch[0].rm_so = 0;
1033         pmatch[0].rm_eo = size;
1034         return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1035 }
1036
1037 #ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1038 # define FORCE_DIR_SET_GID S_ISGID
1039 #else
1040 # define FORCE_DIR_SET_GID 0
1041 #endif
1042
1043 #ifdef NO_NSEC
1044 #undef USE_NSEC
1045 #define ST_CTIME_NSEC(st) 0
1046 #define ST_MTIME_NSEC(st) 0
1047 #else
1048 #ifdef USE_ST_TIMESPEC
1049 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1050 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1051 #else
1052 #define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1053 #define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1054 #endif
1055 #endif
1056
1057 #ifdef UNRELIABLE_FSTAT
1058 #define fstat_is_reliable() 0
1059 #else
1060 #define fstat_is_reliable() 1
1061 #endif
1062
1063 #ifndef va_copy
1064 /*
1065  * Since an obvious implementation of va_list would be to make it a
1066  * pointer into the stack frame, a simple assignment will work on
1067  * many systems.  But let's try to be more portable.
1068  */
1069 #ifdef __va_copy
1070 #define va_copy(dst, src) __va_copy(dst, src)
1071 #else
1072 #define va_copy(dst, src) ((dst) = (src))
1073 #endif
1074 #endif
1075
1076 #if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
1077 #define HAVE_VARIADIC_MACROS 1
1078 #endif
1079
1080 #ifdef HAVE_VARIADIC_MACROS
1081 __attribute__((format (printf, 3, 4))) NORETURN
1082 void BUG_fl(const char *file, int line, const char *fmt, ...);
1083 #define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1084 #else
1085 __attribute__((format (printf, 1, 2))) NORETURN
1086 void BUG(const char *fmt, ...);
1087 #endif
1088
1089 /*
1090  * Preserves errno, prints a message, but gives no warning for ENOENT.
1091  * Returns 0 on success, which includes trying to unlink an object that does
1092  * not exist.
1093  */
1094 int unlink_or_warn(const char *path);
1095  /*
1096   * Tries to unlink file.  Returns 0 if unlink succeeded
1097   * or the file already didn't exist.  Returns -1 and
1098   * appends a message to err suitable for
1099   * 'error("%s", err->buf)' on error.
1100   */
1101 int unlink_or_msg(const char *file, struct strbuf *err);
1102 /*
1103  * Preserves errno, prints a message, but gives no warning for ENOENT.
1104  * Returns 0 on success, which includes trying to remove a directory that does
1105  * not exist.
1106  */
1107 int rmdir_or_warn(const char *path);
1108 /*
1109  * Calls the correct function out of {unlink,rmdir}_or_warn based on
1110  * the supplied file mode.
1111  */
1112 int remove_or_warn(unsigned int mode, const char *path);
1113
1114 /*
1115  * Call access(2), but warn for any error except "missing file"
1116  * (ENOENT or ENOTDIR).
1117  */
1118 #define ACCESS_EACCES_OK (1U << 0)
1119 int access_or_warn(const char *path, int mode, unsigned flag);
1120 int access_or_die(const char *path, int mode, unsigned flag);
1121
1122 /* Warn on an inaccessible file if errno indicates this is an error */
1123 int warn_on_fopen_errors(const char *path);
1124
1125 #ifdef GMTIME_UNRELIABLE_ERRORS
1126 struct tm *git_gmtime(const time_t *);
1127 struct tm *git_gmtime_r(const time_t *, struct tm *);
1128 #define gmtime git_gmtime
1129 #define gmtime_r git_gmtime_r
1130 #endif
1131
1132 #if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1133 #define USE_PARENS_AROUND_GETTEXT_N 1
1134 #endif
1135
1136 #ifndef SHELL_PATH
1137 # define SHELL_PATH "/bin/sh"
1138 #endif
1139
1140 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1141 #define flockfile(fh)
1142 #define funlockfile(fh)
1143 #define getc_unlocked(fh) getc(fh)
1144 #endif
1145
1146 /*
1147  * Our code often opens a path to an optional file, to work on its
1148  * contents when we can successfully open it.  We can ignore a failure
1149  * to open if such an optional file does not exist, but we do want to
1150  * report a failure in opening for other reasons (e.g. we got an I/O
1151  * error, or the file is there, but we lack the permission to open).
1152  *
1153  * Call this function after seeing an error from open() or fopen() to
1154  * see if the errno indicates a missing file that we can safely ignore.
1155  */
1156 static inline int is_missing_file_error(int errno_)
1157 {
1158         return (errno_ == ENOENT || errno_ == ENOTDIR);
1159 }
1160
1161 extern int cmd_main(int, const char **);
1162
1163 #endif