Andrew's git - gitweb.git/blob

   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#ifdef __GNUC__
 100#define TYPEOF(x) (__typeof__(x))
 101#else
 102#define TYPEOF(x)
 103#endif
 104
 105#define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (bitsizeof(x) - (bits))))
 106#define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
 107
 108#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
 109
 110/* Approximation of the length of the decimal representation of this type. */
 111#define decimal_length(x)       ((int)(sizeof(x) * 2.56 + 0.5) + 1)
 112
 113#if defined(__sun__)
 114 /*
 115  * On Solaris, when _XOPEN_EXTENDED is set, its header file
 116  * forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
 117  * setting to say we are XPG5 or XPG6.  Also on Solaris,
 118  * XPG6 programs must be compiled with a c99 compiler, while
 119  * non XPG6 programs must be compiled with a pre-c99 compiler.
 120  */
 121# if __STDC_VERSION__ - 0 >= 199901L
 122# define _XOPEN_SOURCE 600
 123# else
 124# define _XOPEN_SOURCE 500
 125# endif
 126#elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
 127      !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__) && \
 128      !defined(__TANDEM) && !defined(__QNX__) && !defined(__MirBSD__)
 129#define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 130#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 131#endif
 132#define _ALL_SOURCE 1
 133#define _GNU_SOURCE 1
 134#define _BSD_SOURCE 1
 135#define _DEFAULT_SOURCE 1
 136#define _NETBSD_SOURCE 1
 137#define _SGI_SOURCE 1
 138
 139#if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 140# if defined (_MSC_VER) && !defined(_WIN32_WINNT)
 141#  define _WIN32_WINNT 0x0502
 142# endif
 143#define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 144#include <winsock2.h>
 145#include <windows.h>
 146#define GIT_WINDOWS_NATIVE
 147#endif
 148
 149#include <unistd.h>
 150#include <stdio.h>
 151#include <sys/stat.h>
 152#include <fcntl.h>
 153#include <stddef.h>
 154#include <stdlib.h>
 155#include <stdarg.h>
 156#include <string.h>
 157#ifdef HAVE_STRINGS_H
 158#include <strings.h> /* for strcasecmp() */
 159#endif
 160#include <errno.h>
 161#include <limits.h>
 162#ifdef NEEDS_SYS_PARAM_H
 163#include <sys/param.h>
 164#endif
 165#include <sys/types.h>
 166#include <dirent.h>
 167#include <sys/time.h>
 168#include <time.h>
 169#include <signal.h>
 170#include <assert.h>
 171#include <regex.h>
 172#include <utime.h>
 173#include <syslog.h>
 174#ifndef NO_SYS_POLL_H
 175#include <sys/poll.h>
 176#else
 177#include <poll.h>
 178#endif
 179
 180#if defined(__MINGW32__)
 181/* pull in Windows compatibility stuff */
 182#include "compat/mingw.h"
 183#elif defined(_MSC_VER)
 184#include "compat/msvc.h"
 185#else
 186#include <sys/wait.h>
 187#include <sys/resource.h>
 188#include <sys/socket.h>
 189#include <sys/ioctl.h>
 190#include <termios.h>
 191#ifndef NO_SYS_SELECT_H
 192#include <sys/select.h>
 193#endif
 194#include <netinet/in.h>
 195#include <netinet/tcp.h>
 196#include <arpa/inet.h>
 197#include <netdb.h>
 198#include <pwd.h>
 199#include <sys/un.h>
 200#ifndef NO_INTTYPES_H
 201#include <inttypes.h>
 202#else
 203#include <stdint.h>
 204#endif
 205#ifdef NO_INTPTR_T
 206/*
 207 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
 208 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 209 * while on IP16 and IP16L32 it is "int" (resp. "short")
 210 * Size needs to match (or exceed) 'sizeof(void *)'.
 211 * We can't take "long long" here as not everybody has it.
 212 */
 213typedef long intptr_t;
 214typedef unsigned long uintptr_t;
 215#endif
 216#if defined(__CYGWIN__)
 217#undef _XOPEN_SOURCE
 218#include <grp.h>
 219#define _XOPEN_SOURCE 600
 220#else
 221#undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 222#include <grp.h>
 223#define _ALL_SOURCE 1
 224#endif
 225#endif
 226
 227/* used on Mac OS X */
 228#ifdef PRECOMPOSE_UNICODE
 229#include "compat/precompose_utf8.h"
 230#else
 231#define precompose_str(in,i_nfd2nfc)
 232#define precompose_argv(c,v)
 233#define probe_utf8_pathname_composition(a,b)
 234#endif
 235
 236#ifdef MKDIR_WO_TRAILING_SLASH
 237#define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 238extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 239#endif
 240
 241#ifdef NO_STRUCT_ITIMERVAL
 242struct itimerval {
 243        struct timeval it_interval;
 244        struct timeval it_value;
 245};
 246#endif
 247
 248#ifdef NO_SETITIMER
 249#define setitimer(which,value,ovalue)
 250#endif
 251
 252#ifndef NO_LIBGEN_H
 253#include <libgen.h>
 254#else
 255#define basename gitbasename
 256extern char *gitbasename(char *);
 257#endif
 258
 259#ifndef NO_ICONV
 260#include <iconv.h>
 261#endif
 262
 263#ifndef NO_OPENSSL
 264#include <openssl/ssl.h>
 265#include <openssl/err.h>
 266#endif
 267
 268/* On most systems <netdb.h> would have given us this, but
 269 * not on some systems (e.g. z/OS).
 270 */
 271#ifndef NI_MAXHOST
 272#define NI_MAXHOST 1025
 273#endif
 274
 275#ifndef NI_MAXSERV
 276#define NI_MAXSERV 32
 277#endif
 278
 279/* On most systems <limits.h> would have given us this, but
 280 * not on some systems (e.g. GNU/Hurd).
 281 */
 282#ifndef PATH_MAX
 283#define PATH_MAX 4096
 284#endif
 285
 286#ifndef PRIuMAX
 287#define PRIuMAX "llu"
 288#endif
 289
 290#ifndef PRIu32
 291#define PRIu32 "u"
 292#endif
 293
 294#ifndef PRIx32
 295#define PRIx32 "x"
 296#endif
 297
 298#ifndef PRIo32
 299#define PRIo32 "o"
 300#endif
 301
 302#ifndef PATH_SEP
 303#define PATH_SEP ':'
 304#endif
 305
 306#ifdef HAVE_PATHS_H
 307#include <paths.h>
 308#endif
 309#ifndef _PATH_DEFPATH
 310#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 311#endif
 312
 313#ifndef STRIP_EXTENSION
 314#define STRIP_EXTENSION ""
 315#endif
 316
 317#ifndef has_dos_drive_prefix
 318static inline int git_has_dos_drive_prefix(const char *path)
 319{
 320        return 0;
 321}
 322#define has_dos_drive_prefix git_has_dos_drive_prefix
 323#endif
 324
 325#ifndef is_dir_sep
 326static inline int git_is_dir_sep(int c)
 327{
 328        return c == '/';
 329}
 330#define is_dir_sep git_is_dir_sep
 331#endif
 332
 333#ifndef offset_1st_component
 334static inline int git_offset_1st_component(const char *path)
 335{
 336        return is_dir_sep(path[0]);
 337}
 338#define offset_1st_component git_offset_1st_component
 339#endif
 340
 341#ifndef find_last_dir_sep
 342static inline char *git_find_last_dir_sep(const char *path)
 343{
 344        return strrchr(path, '/');
 345}
 346#define find_last_dir_sep git_find_last_dir_sep
 347#endif
 348
 349#if defined(__HP_cc) && (__HP_cc >= 61000)
 350#define NORETURN __attribute__((noreturn))
 351#define NORETURN_PTR
 352#elif defined(__GNUC__) && !defined(NO_NORETURN)
 353#define NORETURN __attribute__((__noreturn__))
 354#define NORETURN_PTR __attribute__((__noreturn__))
 355#elif defined(_MSC_VER)
 356#define NORETURN __declspec(noreturn)
 357#define NORETURN_PTR
 358#else
 359#define NORETURN
 360#define NORETURN_PTR
 361#ifndef __GNUC__
 362#ifndef __attribute__
 363#define __attribute__(x)
 364#endif
 365#endif
 366#endif
 367
 368/* The sentinel attribute is valid from gcc version 4.0 */
 369#if defined(__GNUC__) && (__GNUC__ >= 4)
 370#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 371#else
 372#define LAST_ARG_MUST_BE_NULL
 373#endif
 374
 375#include "compat/bswap.h"
 376
 377#include "wildmatch.h"
 378
 379struct strbuf;
 380
 381/* General helper functions */
 382extern void vreportf(const char *prefix, const char *err, va_list params);
 383extern void vwritef(int fd, const char *prefix, const char *err, va_list params);
 384extern NORETURN void usage(const char *err);
 385extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 386extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 387extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 388extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 389extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 390
 391#ifndef NO_OPENSSL
 392#ifdef APPLE_COMMON_CRYPTO
 393#include "compat/apple-common-crypto.h"
 394#else
 395#include <openssl/evp.h>
 396#include <openssl/hmac.h>
 397#endif /* APPLE_COMMON_CRYPTO */
 398#include <openssl/x509v3.h>
 399#endif /* NO_OPENSSL */
 400
 401/*
 402 * Let callers be aware of the constant return value; this can help
 403 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 404 * because some compilers may not support variadic macros. Since we're only
 405 * trying to help gcc, anyway, it's OK; other compilers will fall back to
 406 * using the function as usual.
 407 */
 408#if defined(__GNUC__)
 409static inline int const_error(void)
 410{
 411        return -1;
 412}
 413#define error(...) (error(__VA_ARGS__), const_error())
 414#endif
 415
 416extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 417extern void set_error_routine(void (*routine)(const char *err, va_list params));
 418extern void set_die_is_recursing_routine(int (*routine)(void));
 419
 420extern int starts_with(const char *str, const char *prefix);
 421
 422/*
 423 * If the string "str" begins with the string found in "prefix", return 1.
 424 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 425 * the string right after the prefix).
 426 *
 427 * Otherwise, return 0 and leave "out" untouched.
 428 *
 429 * Examples:
 430 *
 431 *   [extract branch name, fail if not a branch]
 432 *   if (!skip_prefix(ref, "refs/heads/", &branch)
 433 *      return -1;
 434 *
 435 *   [skip prefix if present, otherwise use whole string]
 436 *   skip_prefix(name, "refs/heads/", &name);
 437 */
 438static inline int skip_prefix(const char *str, const char *prefix,
 439                              const char **out)
 440{
 441        do {
 442                if (!*prefix) {
 443                        *out = str;
 444                        return 1;
 445                }
 446        } while (*str++ == *prefix++);
 447        return 0;
 448}
 449
 450/*
 451 * If buf ends with suffix, return 1 and subtract the length of the suffix
 452 * from *len. Otherwise, return 0 and leave *len untouched.
 453 */
 454static inline int strip_suffix_mem(const char *buf, size_t *len,
 455                                   const char *suffix)
 456{
 457        size_t suflen = strlen(suffix);
 458        if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 459                return 0;
 460        *len -= suflen;
 461        return 1;
 462}
 463
 464/*
 465 * If str ends with suffix, return 1 and set *len to the size of the string
 466 * without the suffix. Otherwise, return 0 and set *len to the size of the
 467 * string.
 468 *
 469 * Note that we do _not_ NUL-terminate str to the new length.
 470 */
 471static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 472{
 473        *len = strlen(str);
 474        return strip_suffix_mem(str, len, suffix);
 475}
 476
 477static inline int ends_with(const char *str, const char *suffix)
 478{
 479        size_t len;
 480        return strip_suffix(str, suffix, &len);
 481}
 482
 483#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 484
 485#ifndef PROT_READ
 486#define PROT_READ 1
 487#define PROT_WRITE 2
 488#define MAP_PRIVATE 1
 489#endif
 490
 491#define mmap git_mmap
 492#define munmap git_munmap
 493extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 494extern int git_munmap(void *start, size_t length);
 495
 496#else /* NO_MMAP || USE_WIN32_MMAP */
 497
 498#include <sys/mman.h>
 499
 500#endif /* NO_MMAP || USE_WIN32_MMAP */
 501
 502#ifdef NO_MMAP
 503
 504/* This value must be multiple of (pagesize * 2) */
 505#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 506
 507#else /* NO_MMAP */
 508
 509/* This value must be multiple of (pagesize * 2) */
 510#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 511        (sizeof(void*) >= 8 \
 512                ?  1 * 1024 * 1024 * 1024 \
 513                : 32 * 1024 * 1024)
 514
 515#endif /* NO_MMAP */
 516
 517#ifndef MAP_FAILED
 518#define MAP_FAILED ((void *)-1)
 519#endif
 520
 521#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 522#define on_disk_bytes(st) ((st).st_size)
 523#else
 524#define on_disk_bytes(st) ((st).st_blocks * 512)
 525#endif
 526
 527#define DEFAULT_PACKED_GIT_LIMIT \
 528        ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
 529
 530#ifdef NO_PREAD
 531#define pread git_pread
 532extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 533#endif
 534/*
 535 * Forward decl that will remind us if its twin in cache.h changes.
 536 * This function is used in compat/pread.c.  But we can't include
 537 * cache.h there.
 538 */
 539extern ssize_t read_in_full(int fd, void *buf, size_t count);
 540
 541#ifdef NO_SETENV
 542#define setenv gitsetenv
 543extern int gitsetenv(const char *, const char *, int);
 544#endif
 545
 546#ifdef NO_MKDTEMP
 547#define mkdtemp gitmkdtemp
 548extern char *gitmkdtemp(char *);
 549#endif
 550
 551#ifdef NO_MKSTEMPS
 552#define mkstemps gitmkstemps
 553extern int gitmkstemps(char *, int);
 554#endif
 555
 556#ifdef NO_UNSETENV
 557#define unsetenv gitunsetenv
 558extern void gitunsetenv(const char *);
 559#endif
 560
 561#ifdef NO_STRCASESTR
 562#define strcasestr gitstrcasestr
 563extern char *gitstrcasestr(const char *haystack, const char *needle);
 564#endif
 565
 566#ifdef NO_STRLCPY
 567#define strlcpy gitstrlcpy
 568extern size_t gitstrlcpy(char *, const char *, size_t);
 569#endif
 570
 571#ifdef NO_STRTOUMAX
 572#define strtoumax gitstrtoumax
 573extern uintmax_t gitstrtoumax(const char *, char **, int);
 574#define strtoimax gitstrtoimax
 575extern intmax_t gitstrtoimax(const char *, char **, int);
 576#endif
 577
 578#ifdef NO_HSTRERROR
 579#define hstrerror githstrerror
 580extern const char *githstrerror(int herror);
 581#endif
 582
 583#ifdef NO_MEMMEM
 584#define memmem gitmemmem
 585void *gitmemmem(const void *haystack, size_t haystacklen,
 586                const void *needle, size_t needlelen);
 587#endif
 588
 589#ifdef NO_GETPAGESIZE
 590#define getpagesize() sysconf(_SC_PAGESIZE)
 591#endif
 592
 593#ifdef FREAD_READS_DIRECTORIES
 594#ifdef fopen
 595#undef fopen
 596#endif
 597#define fopen(a,b) git_fopen(a,b)
 598extern FILE *git_fopen(const char*, const char*);
 599#endif
 600
 601#ifdef SNPRINTF_RETURNS_BOGUS
 602#ifdef snprintf
 603#undef snprintf
 604#endif
 605#define snprintf git_snprintf
 606extern int git_snprintf(char *str, size_t maxsize,
 607                        const char *format, ...);
 608#ifdef vsnprintf
 609#undef vsnprintf
 610#endif
 611#define vsnprintf git_vsnprintf
 612extern int git_vsnprintf(char *str, size_t maxsize,
 613                         const char *format, va_list ap);
 614#endif
 615
 616#ifdef __GLIBC_PREREQ
 617#if __GLIBC_PREREQ(2, 1)
 618#define HAVE_STRCHRNUL
 619#define HAVE_MEMPCPY
 620#endif
 621#endif
 622
 623#ifndef HAVE_STRCHRNUL
 624#define strchrnul gitstrchrnul
 625static inline char *gitstrchrnul(const char *s, int c)
 626{
 627        while (*s && *s != c)
 628                s++;
 629        return (char *)s;
 630}
 631#endif
 632
 633#ifndef HAVE_MEMPCPY
 634#define mempcpy gitmempcpy
 635static inline void *gitmempcpy(void *dest, const void *src, size_t n)
 636{
 637        return (char *)memcpy(dest, src, n) + n;
 638}
 639#endif
 640
 641#ifdef NO_INET_PTON
 642int inet_pton(int af, const char *src, void *dst);
 643#endif
 644
 645#ifdef NO_INET_NTOP
 646const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 647#endif
 648
 649#ifdef NO_PTHREADS
 650#define atexit git_atexit
 651extern int git_atexit(void (*handler)(void));
 652#endif
 653
 654extern void release_pack_memory(size_t);
 655
 656typedef void (*try_to_free_t)(size_t);
 657extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 658
 659#ifdef HAVE_ALLOCA_H
 660# include <alloca.h>
 661# define xalloca(size)      (alloca(size))
 662# define xalloca_free(p)    do {} while (0)
 663#else
 664# define xalloca(size)      (xmalloc(size))
 665# define xalloca_free(p)    (free(p))
 666#endif
 667extern char *xstrdup(const char *str);
 668extern void *xmalloc(size_t size);
 669extern void *xmallocz(size_t size);
 670extern void *xmallocz_gently(size_t size);
 671extern void *xmemdupz(const void *data, size_t len);
 672extern char *xstrndup(const char *str, size_t len);
 673extern void *xrealloc(void *ptr, size_t size);
 674extern void *xcalloc(size_t nmemb, size_t size);
 675extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 676extern ssize_t xread(int fd, void *buf, size_t len);
 677extern ssize_t xwrite(int fd, const void *buf, size_t len);
 678extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 679extern int xdup(int fd);
 680extern FILE *xfdopen(int fd, const char *mode);
 681extern int xmkstemp(char *template);
 682extern int xmkstemp_mode(char *template, int mode);
 683extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
 684extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
 685extern char *xgetcwd(void);
 686
 687#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), (alloc) * sizeof(*(x)))
 688
 689static inline size_t xsize_t(off_t len)
 690{
 691        if (len > (size_t) len)
 692                die("Cannot handle files this big");
 693        return (size_t)len;
 694}
 695
 696/* in ctype.c, for kwset users */
 697extern const char tolower_trans_tbl[256];
 698
 699/* Sane ctype - no locale, and works with signed chars */
 700#undef isascii
 701#undef isspace
 702#undef isdigit
 703#undef isalpha
 704#undef isalnum
 705#undef isprint
 706#undef islower
 707#undef isupper
 708#undef tolower
 709#undef toupper
 710#undef iscntrl
 711#undef ispunct
 712#undef isxdigit
 713
 714extern const unsigned char sane_ctype[256];
 715#define GIT_SPACE 0x01
 716#define GIT_DIGIT 0x02
 717#define GIT_ALPHA 0x04
 718#define GIT_GLOB_SPECIAL 0x08
 719#define GIT_REGEX_SPECIAL 0x10
 720#define GIT_PATHSPEC_MAGIC 0x20
 721#define GIT_CNTRL 0x40
 722#define GIT_PUNCT 0x80
 723#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 724#define isascii(x) (((x) & ~0x7f) == 0)
 725#define isspace(x) sane_istest(x,GIT_SPACE)
 726#define isdigit(x) sane_istest(x,GIT_DIGIT)
 727#define isalpha(x) sane_istest(x,GIT_ALPHA)
 728#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 729#define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 730#define islower(x) sane_iscase(x, 1)
 731#define isupper(x) sane_iscase(x, 0)
 732#define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 733#define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 734#define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 735#define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 736                GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 737#define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 738#define tolower(x) sane_case((unsigned char)(x), 0x20)
 739#define toupper(x) sane_case((unsigned char)(x), 0)
 740#define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 741
 742static inline int sane_case(int x, int high)
 743{
 744        if (sane_istest(x, GIT_ALPHA))
 745                x = (x & ~0x20) | high;
 746        return x;
 747}
 748
 749static inline int sane_iscase(int x, int is_lower)
 750{
 751        if (!sane_istest(x, GIT_ALPHA))
 752                return 0;
 753
 754        if (is_lower)
 755                return (x & 0x20) != 0;
 756        else
 757                return (x & 0x20) == 0;
 758}
 759
 760static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 761{
 762        unsigned long ul;
 763        char *p;
 764
 765        errno = 0;
 766        ul = strtoul(s, &p, base);
 767        if (errno || *p || p == s || (unsigned int) ul != ul)
 768                return -1;
 769        *result = ul;
 770        return 0;
 771}
 772
 773static inline int strtol_i(char const *s, int base, int *result)
 774{
 775        long ul;
 776        char *p;
 777
 778        errno = 0;
 779        ul = strtol(s, &p, base);
 780        if (errno || *p || p == s || (int) ul != ul)
 781                return -1;
 782        *result = ul;
 783        return 0;
 784}
 785
 786#ifdef INTERNAL_QSORT
 787void git_qsort(void *base, size_t nmemb, size_t size,
 788               int(*compar)(const void *, const void *));
 789#define qsort git_qsort
 790#endif
 791
 792#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
 793# define FORCE_DIR_SET_GID S_ISGID
 794#else
 795# define FORCE_DIR_SET_GID 0
 796#endif
 797
 798#ifdef NO_NSEC
 799#undef USE_NSEC
 800#define ST_CTIME_NSEC(st) 0
 801#define ST_MTIME_NSEC(st) 0
 802#else
 803#ifdef USE_ST_TIMESPEC
 804#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
 805#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
 806#else
 807#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
 808#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
 809#endif
 810#endif
 811
 812#ifdef UNRELIABLE_FSTAT
 813#define fstat_is_reliable() 0
 814#else
 815#define fstat_is_reliable() 1
 816#endif
 817
 818#ifndef va_copy
 819/*
 820 * Since an obvious implementation of va_list would be to make it a
 821 * pointer into the stack frame, a simple assignment will work on
 822 * many systems.  But let's try to be more portable.
 823 */
 824#ifdef __va_copy
 825#define va_copy(dst, src) __va_copy(dst, src)
 826#else
 827#define va_copy(dst, src) ((dst) = (src))
 828#endif
 829#endif
 830
 831#if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
 832#define HAVE_VARIADIC_MACROS 1
 833#endif
 834
 835/*
 836 * Preserves errno, prints a message, but gives no warning for ENOENT.
 837 * Returns 0 on success, which includes trying to unlink an object that does
 838 * not exist.
 839 */
 840int unlink_or_warn(const char *path);
 841 /*
 842  * Tries to unlink file.  Returns 0 if unlink succeeded
 843  * or the file already didn't exist.  Returns -1 and
 844  * appends a message to err suitable for
 845  * 'error("%s", err->buf)' on error.
 846  */
 847int unlink_or_msg(const char *file, struct strbuf *err);
 848/*
 849 * Preserves errno, prints a message, but gives no warning for ENOENT.
 850 * Returns 0 on success, which includes trying to remove a directory that does
 851 * not exist.
 852 */
 853int rmdir_or_warn(const char *path);
 854/*
 855 * Calls the correct function out of {unlink,rmdir}_or_warn based on
 856 * the supplied file mode.
 857 */
 858int remove_or_warn(unsigned int mode, const char *path);
 859
 860/*
 861 * Call access(2), but warn for any error except "missing file"
 862 * (ENOENT or ENOTDIR).
 863 */
 864#define ACCESS_EACCES_OK (1U << 0)
 865int access_or_warn(const char *path, int mode, unsigned flag);
 866int access_or_die(const char *path, int mode, unsigned flag);
 867
 868/* Warn on an inaccessible file that ought to be accessible */
 869void warn_on_inaccessible(const char *path);
 870
 871/* Get the passwd entry for the UID of the current process. */
 872struct passwd *xgetpwuid_self(void);
 873
 874#ifdef GMTIME_UNRELIABLE_ERRORS
 875struct tm *git_gmtime(const time_t *);
 876struct tm *git_gmtime_r(const time_t *, struct tm *);
 877#define gmtime git_gmtime
 878#define gmtime_r git_gmtime_r
 879#endif
 880
 881#endif