git-compat-util.hon commit sha1_file: consolidate code to close a pack's file descriptor (71fe5d7)
   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      !defined(__CYGWIN__)
 130#define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
 131#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
 132#endif
 133#define _ALL_SOURCE 1
 134#define _GNU_SOURCE 1
 135#define _BSD_SOURCE 1
 136#define _DEFAULT_SOURCE 1
 137#define _NETBSD_SOURCE 1
 138#define _SGI_SOURCE 1
 139
 140#if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
 141# if defined (_MSC_VER) && !defined(_WIN32_WINNT)
 142#  define _WIN32_WINNT 0x0502
 143# endif
 144#define WIN32_LEAN_AND_MEAN  /* stops windows.h including winsock.h */
 145#include <winsock2.h>
 146#include <windows.h>
 147#define GIT_WINDOWS_NATIVE
 148#endif
 149
 150#include <unistd.h>
 151#include <stdio.h>
 152#include <sys/stat.h>
 153#include <fcntl.h>
 154#include <stddef.h>
 155#include <stdlib.h>
 156#include <stdarg.h>
 157#include <string.h>
 158#ifdef HAVE_STRINGS_H
 159#include <strings.h> /* for strcasecmp() */
 160#endif
 161#include <errno.h>
 162#include <limits.h>
 163#ifdef NEEDS_SYS_PARAM_H
 164#include <sys/param.h>
 165#endif
 166#include <sys/types.h>
 167#include <dirent.h>
 168#include <sys/time.h>
 169#include <time.h>
 170#include <signal.h>
 171#include <assert.h>
 172#include <regex.h>
 173#include <utime.h>
 174#include <syslog.h>
 175#ifndef NO_SYS_POLL_H
 176#include <sys/poll.h>
 177#else
 178#include <poll.h>
 179#endif
 180#ifdef HAVE_BSD_SYSCTL
 181#include <sys/sysctl.h>
 182#endif
 183
 184#if defined(__MINGW32__)
 185/* pull in Windows compatibility stuff */
 186#include "compat/mingw.h"
 187#elif defined(_MSC_VER)
 188#include "compat/msvc.h"
 189#else
 190#include <sys/wait.h>
 191#include <sys/resource.h>
 192#include <sys/socket.h>
 193#include <sys/ioctl.h>
 194#include <termios.h>
 195#ifndef NO_SYS_SELECT_H
 196#include <sys/select.h>
 197#endif
 198#include <netinet/in.h>
 199#include <netinet/tcp.h>
 200#include <arpa/inet.h>
 201#include <netdb.h>
 202#include <pwd.h>
 203#include <sys/un.h>
 204#ifndef NO_INTTYPES_H
 205#include <inttypes.h>
 206#else
 207#include <stdint.h>
 208#endif
 209#ifdef NO_INTPTR_T
 210/*
 211 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
 212 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 213 * while on IP16 and IP16L32 it is "int" (resp. "short")
 214 * Size needs to match (or exceed) 'sizeof(void *)'.
 215 * We can't take "long long" here as not everybody has it.
 216 */
 217typedef long intptr_t;
 218typedef unsigned long uintptr_t;
 219#endif
 220#undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 221#include <grp.h>
 222#define _ALL_SOURCE 1
 223#endif
 224
 225/* used on Mac OS X */
 226#ifdef PRECOMPOSE_UNICODE
 227#include "compat/precompose_utf8.h"
 228#else
 229#define precompose_str(in,i_nfd2nfc)
 230#define precompose_argv(c,v)
 231#define probe_utf8_pathname_composition(a,b)
 232#endif
 233
 234#ifdef MKDIR_WO_TRAILING_SLASH
 235#define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 236extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 237#endif
 238
 239#ifdef NO_STRUCT_ITIMERVAL
 240struct itimerval {
 241        struct timeval it_interval;
 242        struct timeval it_value;
 243};
 244#endif
 245
 246#ifdef NO_SETITIMER
 247#define setitimer(which,value,ovalue)
 248#endif
 249
 250#ifndef NO_LIBGEN_H
 251#include <libgen.h>
 252#else
 253#define basename gitbasename
 254extern char *gitbasename(char *);
 255#endif
 256
 257#ifndef NO_ICONV
 258#include <iconv.h>
 259#endif
 260
 261#ifndef NO_OPENSSL
 262#ifdef __APPLE__
 263#define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 264#include <AvailabilityMacros.h>
 265#undef DEPRECATED_ATTRIBUTE
 266#define DEPRECATED_ATTRIBUTE
 267#undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 268#endif
 269#include <openssl/ssl.h>
 270#include <openssl/err.h>
 271#ifdef NO_HMAC_CTX_CLEANUP
 272#define HMAC_CTX_cleanup HMAC_cleanup
 273#endif
 274#endif
 275
 276/* On most systems <netdb.h> would have given us this, but
 277 * not on some systems (e.g. z/OS).
 278 */
 279#ifndef NI_MAXHOST
 280#define NI_MAXHOST 1025
 281#endif
 282
 283#ifndef NI_MAXSERV
 284#define NI_MAXSERV 32
 285#endif
 286
 287/* On most systems <limits.h> would have given us this, but
 288 * not on some systems (e.g. GNU/Hurd).
 289 */
 290#ifndef PATH_MAX
 291#define PATH_MAX 4096
 292#endif
 293
 294#ifndef PRIuMAX
 295#define PRIuMAX "llu"
 296#endif
 297
 298#ifndef PRIu32
 299#define PRIu32 "u"
 300#endif
 301
 302#ifndef PRIx32
 303#define PRIx32 "x"
 304#endif
 305
 306#ifndef PRIo32
 307#define PRIo32 "o"
 308#endif
 309
 310#ifndef PATH_SEP
 311#define PATH_SEP ':'
 312#endif
 313
 314#ifdef HAVE_PATHS_H
 315#include <paths.h>
 316#endif
 317#ifndef _PATH_DEFPATH
 318#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 319#endif
 320
 321#ifndef STRIP_EXTENSION
 322#define STRIP_EXTENSION ""
 323#endif
 324
 325#ifndef has_dos_drive_prefix
 326static inline int git_has_dos_drive_prefix(const char *path)
 327{
 328        return 0;
 329}
 330#define has_dos_drive_prefix git_has_dos_drive_prefix
 331#endif
 332
 333#ifndef is_dir_sep
 334static inline int git_is_dir_sep(int c)
 335{
 336        return c == '/';
 337}
 338#define is_dir_sep git_is_dir_sep
 339#endif
 340
 341#ifndef offset_1st_component
 342static inline int git_offset_1st_component(const char *path)
 343{
 344        return is_dir_sep(path[0]);
 345}
 346#define offset_1st_component git_offset_1st_component
 347#endif
 348
 349#ifndef find_last_dir_sep
 350static inline char *git_find_last_dir_sep(const char *path)
 351{
 352        return strrchr(path, '/');
 353}
 354#define find_last_dir_sep git_find_last_dir_sep
 355#endif
 356
 357#if defined(__HP_cc) && (__HP_cc >= 61000)
 358#define NORETURN __attribute__((noreturn))
 359#define NORETURN_PTR
 360#elif defined(__GNUC__) && !defined(NO_NORETURN)
 361#define NORETURN __attribute__((__noreturn__))
 362#define NORETURN_PTR __attribute__((__noreturn__))
 363#elif defined(_MSC_VER)
 364#define NORETURN __declspec(noreturn)
 365#define NORETURN_PTR
 366#else
 367#define NORETURN
 368#define NORETURN_PTR
 369#ifndef __GNUC__
 370#ifndef __attribute__
 371#define __attribute__(x)
 372#endif
 373#endif
 374#endif
 375
 376/* The sentinel attribute is valid from gcc version 4.0 */
 377#if defined(__GNUC__) && (__GNUC__ >= 4)
 378#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 379#else
 380#define LAST_ARG_MUST_BE_NULL
 381#endif
 382
 383#include "compat/bswap.h"
 384
 385#include "wildmatch.h"
 386
 387struct strbuf;
 388
 389/* General helper functions */
 390extern void vreportf(const char *prefix, const char *err, va_list params);
 391extern void vwritef(int fd, const char *prefix, const char *err, va_list params);
 392extern NORETURN void usage(const char *err);
 393extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 394extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 395extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 396extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 397extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 398
 399#ifndef NO_OPENSSL
 400#ifdef APPLE_COMMON_CRYPTO
 401#include "compat/apple-common-crypto.h"
 402#else
 403#include <openssl/evp.h>
 404#include <openssl/hmac.h>
 405#endif /* APPLE_COMMON_CRYPTO */
 406#include <openssl/x509v3.h>
 407#endif /* NO_OPENSSL */
 408
 409/*
 410 * Let callers be aware of the constant return value; this can help
 411 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 412 * because some compilers may not support variadic macros. Since we're only
 413 * trying to help gcc, anyway, it's OK; other compilers will fall back to
 414 * using the function as usual.
 415 */
 416#if defined(__GNUC__)
 417static inline int const_error(void)
 418{
 419        return -1;
 420}
 421#define error(...) (error(__VA_ARGS__), const_error())
 422#endif
 423
 424extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 425extern void set_error_routine(void (*routine)(const char *err, va_list params));
 426extern void set_die_is_recursing_routine(int (*routine)(void));
 427
 428extern int starts_with(const char *str, const char *prefix);
 429
 430/*
 431 * If the string "str" begins with the string found in "prefix", return 1.
 432 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 433 * the string right after the prefix).
 434 *
 435 * Otherwise, return 0 and leave "out" untouched.
 436 *
 437 * Examples:
 438 *
 439 *   [extract branch name, fail if not a branch]
 440 *   if (!skip_prefix(ref, "refs/heads/", &branch)
 441 *      return -1;
 442 *
 443 *   [skip prefix if present, otherwise use whole string]
 444 *   skip_prefix(name, "refs/heads/", &name);
 445 */
 446static inline int skip_prefix(const char *str, const char *prefix,
 447                              const char **out)
 448{
 449        do {
 450                if (!*prefix) {
 451                        *out = str;
 452                        return 1;
 453                }
 454        } while (*str++ == *prefix++);
 455        return 0;
 456}
 457
 458/*
 459 * If buf ends with suffix, return 1 and subtract the length of the suffix
 460 * from *len. Otherwise, return 0 and leave *len untouched.
 461 */
 462static inline int strip_suffix_mem(const char *buf, size_t *len,
 463                                   const char *suffix)
 464{
 465        size_t suflen = strlen(suffix);
 466        if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 467                return 0;
 468        *len -= suflen;
 469        return 1;
 470}
 471
 472/*
 473 * If str ends with suffix, return 1 and set *len to the size of the string
 474 * without the suffix. Otherwise, return 0 and set *len to the size of the
 475 * string.
 476 *
 477 * Note that we do _not_ NUL-terminate str to the new length.
 478 */
 479static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 480{
 481        *len = strlen(str);
 482        return strip_suffix_mem(str, len, suffix);
 483}
 484
 485static inline int ends_with(const char *str, const char *suffix)
 486{
 487        size_t len;
 488        return strip_suffix(str, suffix, &len);
 489}
 490
 491#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 492
 493#ifndef PROT_READ
 494#define PROT_READ 1
 495#define PROT_WRITE 2
 496#define MAP_PRIVATE 1
 497#endif
 498
 499#define mmap git_mmap
 500#define munmap git_munmap
 501extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 502extern int git_munmap(void *start, size_t length);
 503
 504#else /* NO_MMAP || USE_WIN32_MMAP */
 505
 506#include <sys/mman.h>
 507
 508#endif /* NO_MMAP || USE_WIN32_MMAP */
 509
 510#ifdef NO_MMAP
 511
 512/* This value must be multiple of (pagesize * 2) */
 513#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 514
 515#else /* NO_MMAP */
 516
 517/* This value must be multiple of (pagesize * 2) */
 518#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 519        (sizeof(void*) >= 8 \
 520                ?  1 * 1024 * 1024 * 1024 \
 521                : 32 * 1024 * 1024)
 522
 523#endif /* NO_MMAP */
 524
 525#ifndef MAP_FAILED
 526#define MAP_FAILED ((void *)-1)
 527#endif
 528
 529#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 530#define on_disk_bytes(st) ((st).st_size)
 531#else
 532#define on_disk_bytes(st) ((st).st_blocks * 512)
 533#endif
 534
 535#ifdef NEEDS_MODE_TRANSLATION
 536#undef S_IFMT
 537#undef S_IFREG
 538#undef S_IFDIR
 539#undef S_IFLNK
 540#undef S_IFBLK
 541#undef S_IFCHR
 542#undef S_IFIFO
 543#undef S_IFSOCK
 544#define S_IFMT   0170000
 545#define S_IFREG  0100000
 546#define S_IFDIR  0040000
 547#define S_IFLNK  0120000
 548#define S_IFBLK  0060000
 549#define S_IFCHR  0020000
 550#define S_IFIFO  0010000
 551#define S_IFSOCK 0140000
 552#ifdef stat
 553#undef stat
 554#endif
 555#define stat(path, buf) git_stat(path, buf)
 556extern int git_stat(const char *, struct stat *);
 557#ifdef fstat
 558#undef fstat
 559#endif
 560#define fstat(fd, buf) git_fstat(fd, buf)
 561extern int git_fstat(int, struct stat *);
 562#ifdef lstat
 563#undef lstat
 564#endif
 565#define lstat(path, buf) git_lstat(path, buf)
 566extern int git_lstat(const char *, struct stat *);
 567#endif
 568
 569#define DEFAULT_PACKED_GIT_LIMIT \
 570        ((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
 571
 572#ifdef NO_PREAD
 573#define pread git_pread
 574extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 575#endif
 576/*
 577 * Forward decl that will remind us if its twin in cache.h changes.
 578 * This function is used in compat/pread.c.  But we can't include
 579 * cache.h there.
 580 */
 581extern ssize_t read_in_full(int fd, void *buf, size_t count);
 582
 583#ifdef NO_SETENV
 584#define setenv gitsetenv
 585extern int gitsetenv(const char *, const char *, int);
 586#endif
 587
 588#ifdef NO_MKDTEMP
 589#define mkdtemp gitmkdtemp
 590extern char *gitmkdtemp(char *);
 591#endif
 592
 593#ifdef NO_MKSTEMPS
 594#define mkstemps gitmkstemps
 595extern int gitmkstemps(char *, int);
 596#endif
 597
 598#ifdef NO_UNSETENV
 599#define unsetenv gitunsetenv
 600extern void gitunsetenv(const char *);
 601#endif
 602
 603#ifdef NO_STRCASESTR
 604#define strcasestr gitstrcasestr
 605extern char *gitstrcasestr(const char *haystack, const char *needle);
 606#endif
 607
 608#ifdef NO_STRLCPY
 609#define strlcpy gitstrlcpy
 610extern size_t gitstrlcpy(char *, const char *, size_t);
 611#endif
 612
 613#ifdef NO_STRTOUMAX
 614#define strtoumax gitstrtoumax
 615extern uintmax_t gitstrtoumax(const char *, char **, int);
 616#define strtoimax gitstrtoimax
 617extern intmax_t gitstrtoimax(const char *, char **, int);
 618#endif
 619
 620#ifdef NO_HSTRERROR
 621#define hstrerror githstrerror
 622extern const char *githstrerror(int herror);
 623#endif
 624
 625#ifdef NO_MEMMEM
 626#define memmem gitmemmem
 627void *gitmemmem(const void *haystack, size_t haystacklen,
 628                const void *needle, size_t needlelen);
 629#endif
 630
 631#ifdef NO_GETPAGESIZE
 632#define getpagesize() sysconf(_SC_PAGESIZE)
 633#endif
 634
 635#ifdef FREAD_READS_DIRECTORIES
 636#ifdef fopen
 637#undef fopen
 638#endif
 639#define fopen(a,b) git_fopen(a,b)
 640extern FILE *git_fopen(const char*, const char*);
 641#endif
 642
 643#ifdef SNPRINTF_RETURNS_BOGUS
 644#ifdef snprintf
 645#undef snprintf
 646#endif
 647#define snprintf git_snprintf
 648extern int git_snprintf(char *str, size_t maxsize,
 649                        const char *format, ...);
 650#ifdef vsnprintf
 651#undef vsnprintf
 652#endif
 653#define vsnprintf git_vsnprintf
 654extern int git_vsnprintf(char *str, size_t maxsize,
 655                         const char *format, va_list ap);
 656#endif
 657
 658#ifdef __GLIBC_PREREQ
 659#if __GLIBC_PREREQ(2, 1)
 660#define HAVE_STRCHRNUL
 661#define HAVE_MEMPCPY
 662#endif
 663#endif
 664
 665#ifndef HAVE_STRCHRNUL
 666#define strchrnul gitstrchrnul
 667static inline char *gitstrchrnul(const char *s, int c)
 668{
 669        while (*s && *s != c)
 670                s++;
 671        return (char *)s;
 672}
 673#endif
 674
 675#ifndef HAVE_MEMPCPY
 676#define mempcpy gitmempcpy
 677static inline void *gitmempcpy(void *dest, const void *src, size_t n)
 678{
 679        return (char *)memcpy(dest, src, n) + n;
 680}
 681#endif
 682
 683#ifdef NO_INET_PTON
 684int inet_pton(int af, const char *src, void *dst);
 685#endif
 686
 687#ifdef NO_INET_NTOP
 688const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 689#endif
 690
 691#ifdef NO_PTHREADS
 692#define atexit git_atexit
 693extern int git_atexit(void (*handler)(void));
 694#endif
 695
 696extern void release_pack_memory(size_t);
 697
 698typedef void (*try_to_free_t)(size_t);
 699extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 700
 701#ifdef HAVE_ALLOCA_H
 702# include <alloca.h>
 703# define xalloca(size)      (alloca(size))
 704# define xalloca_free(p)    do {} while (0)
 705#else
 706# define xalloca(size)      (xmalloc(size))
 707# define xalloca_free(p)    (free(p))
 708#endif
 709extern char *xstrdup(const char *str);
 710extern void *xmalloc(size_t size);
 711extern void *xmallocz(size_t size);
 712extern void *xmallocz_gently(size_t size);
 713extern void *xmemdupz(const void *data, size_t len);
 714extern char *xstrndup(const char *str, size_t len);
 715extern void *xrealloc(void *ptr, size_t size);
 716extern void *xcalloc(size_t nmemb, size_t size);
 717extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 718extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 719extern ssize_t xread(int fd, void *buf, size_t len);
 720extern ssize_t xwrite(int fd, const void *buf, size_t len);
 721extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 722extern int xdup(int fd);
 723extern FILE *xfdopen(int fd, const char *mode);
 724extern int xmkstemp(char *template);
 725extern int xmkstemp_mode(char *template, int mode);
 726extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
 727extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
 728extern char *xgetcwd(void);
 729
 730#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), (alloc) * sizeof(*(x)))
 731
 732static inline char *xstrdup_or_null(const char *str)
 733{
 734        return str ? xstrdup(str) : NULL;
 735}
 736
 737static inline size_t xsize_t(off_t len)
 738{
 739        if (len > (size_t) len)
 740                die("Cannot handle files this big");
 741        return (size_t)len;
 742}
 743
 744/* in ctype.c, for kwset users */
 745extern const unsigned char tolower_trans_tbl[256];
 746
 747/* Sane ctype - no locale, and works with signed chars */
 748#undef isascii
 749#undef isspace
 750#undef isdigit
 751#undef isalpha
 752#undef isalnum
 753#undef isprint
 754#undef islower
 755#undef isupper
 756#undef tolower
 757#undef toupper
 758#undef iscntrl
 759#undef ispunct
 760#undef isxdigit
 761
 762extern const unsigned char sane_ctype[256];
 763#define GIT_SPACE 0x01
 764#define GIT_DIGIT 0x02
 765#define GIT_ALPHA 0x04
 766#define GIT_GLOB_SPECIAL 0x08
 767#define GIT_REGEX_SPECIAL 0x10
 768#define GIT_PATHSPEC_MAGIC 0x20
 769#define GIT_CNTRL 0x40
 770#define GIT_PUNCT 0x80
 771#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 772#define isascii(x) (((x) & ~0x7f) == 0)
 773#define isspace(x) sane_istest(x,GIT_SPACE)
 774#define isdigit(x) sane_istest(x,GIT_DIGIT)
 775#define isalpha(x) sane_istest(x,GIT_ALPHA)
 776#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 777#define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 778#define islower(x) sane_iscase(x, 1)
 779#define isupper(x) sane_iscase(x, 0)
 780#define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 781#define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 782#define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 783#define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 784                GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 785#define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 786#define tolower(x) sane_case((unsigned char)(x), 0x20)
 787#define toupper(x) sane_case((unsigned char)(x), 0)
 788#define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 789
 790static inline int sane_case(int x, int high)
 791{
 792        if (sane_istest(x, GIT_ALPHA))
 793                x = (x & ~0x20) | high;
 794        return x;
 795}
 796
 797static inline int sane_iscase(int x, int is_lower)
 798{
 799        if (!sane_istest(x, GIT_ALPHA))
 800                return 0;
 801
 802        if (is_lower)
 803                return (x & 0x20) != 0;
 804        else
 805                return (x & 0x20) == 0;
 806}
 807
 808static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 809{
 810        unsigned long ul;
 811        char *p;
 812
 813        errno = 0;
 814        ul = strtoul(s, &p, base);
 815        if (errno || *p || p == s || (unsigned int) ul != ul)
 816                return -1;
 817        *result = ul;
 818        return 0;
 819}
 820
 821static inline int strtol_i(char const *s, int base, int *result)
 822{
 823        long ul;
 824        char *p;
 825
 826        errno = 0;
 827        ul = strtol(s, &p, base);
 828        if (errno || *p || p == s || (int) ul != ul)
 829                return -1;
 830        *result = ul;
 831        return 0;
 832}
 833
 834#ifdef INTERNAL_QSORT
 835void git_qsort(void *base, size_t nmemb, size_t size,
 836               int(*compar)(const void *, const void *));
 837#define qsort git_qsort
 838#endif
 839
 840#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
 841# define FORCE_DIR_SET_GID S_ISGID
 842#else
 843# define FORCE_DIR_SET_GID 0
 844#endif
 845
 846#ifdef NO_NSEC
 847#undef USE_NSEC
 848#define ST_CTIME_NSEC(st) 0
 849#define ST_MTIME_NSEC(st) 0
 850#else
 851#ifdef USE_ST_TIMESPEC
 852#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
 853#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
 854#else
 855#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
 856#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
 857#endif
 858#endif
 859
 860#ifdef UNRELIABLE_FSTAT
 861#define fstat_is_reliable() 0
 862#else
 863#define fstat_is_reliable() 1
 864#endif
 865
 866#ifndef va_copy
 867/*
 868 * Since an obvious implementation of va_list would be to make it a
 869 * pointer into the stack frame, a simple assignment will work on
 870 * many systems.  But let's try to be more portable.
 871 */
 872#ifdef __va_copy
 873#define va_copy(dst, src) __va_copy(dst, src)
 874#else
 875#define va_copy(dst, src) ((dst) = (src))
 876#endif
 877#endif
 878
 879#if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
 880#define HAVE_VARIADIC_MACROS 1
 881#endif
 882
 883/*
 884 * Preserves errno, prints a message, but gives no warning for ENOENT.
 885 * Returns 0 on success, which includes trying to unlink an object that does
 886 * not exist.
 887 */
 888int unlink_or_warn(const char *path);
 889 /*
 890  * Tries to unlink file.  Returns 0 if unlink succeeded
 891  * or the file already didn't exist.  Returns -1 and
 892  * appends a message to err suitable for
 893  * 'error("%s", err->buf)' on error.
 894  */
 895int unlink_or_msg(const char *file, struct strbuf *err);
 896/*
 897 * Preserves errno, prints a message, but gives no warning for ENOENT.
 898 * Returns 0 on success, which includes trying to remove a directory that does
 899 * not exist.
 900 */
 901int rmdir_or_warn(const char *path);
 902/*
 903 * Calls the correct function out of {unlink,rmdir}_or_warn based on
 904 * the supplied file mode.
 905 */
 906int remove_or_warn(unsigned int mode, const char *path);
 907
 908/*
 909 * Call access(2), but warn for any error except "missing file"
 910 * (ENOENT or ENOTDIR).
 911 */
 912#define ACCESS_EACCES_OK (1U << 0)
 913int access_or_warn(const char *path, int mode, unsigned flag);
 914int access_or_die(const char *path, int mode, unsigned flag);
 915
 916/* Warn on an inaccessible file that ought to be accessible */
 917void warn_on_inaccessible(const char *path);
 918
 919/* Get the passwd entry for the UID of the current process. */
 920struct passwd *xgetpwuid_self(void);
 921
 922#ifdef GMTIME_UNRELIABLE_ERRORS
 923struct tm *git_gmtime(const time_t *);
 924struct tm *git_gmtime_r(const time_t *, struct tm *);
 925#define gmtime git_gmtime
 926#define gmtime_r git_gmtime_r
 927#endif
 928
 929#if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
 930#define USE_PARENS_AROUND_GETTEXT_N 1
 931#endif
 932
 933#ifndef SHELL_PATH
 934# define SHELL_PATH "/bin/sh"
 935#endif
 936
 937#endif