git-compat-util.hon commit Merge branch 'jk/pack-revindex' (4fd1359)
   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/utsname.h>
 191#include <sys/wait.h>
 192#include <sys/resource.h>
 193#include <sys/socket.h>
 194#include <sys/ioctl.h>
 195#include <termios.h>
 196#ifndef NO_SYS_SELECT_H
 197#include <sys/select.h>
 198#endif
 199#include <netinet/in.h>
 200#include <netinet/tcp.h>
 201#include <arpa/inet.h>
 202#include <netdb.h>
 203#include <pwd.h>
 204#include <sys/un.h>
 205#ifndef NO_INTTYPES_H
 206#include <inttypes.h>
 207#else
 208#include <stdint.h>
 209#endif
 210#ifdef NO_INTPTR_T
 211/*
 212 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
 213 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 214 * while on IP16 and IP16L32 it is "int" (resp. "short")
 215 * Size needs to match (or exceed) 'sizeof(void *)'.
 216 * We can't take "long long" here as not everybody has it.
 217 */
 218typedef long intptr_t;
 219typedef unsigned long uintptr_t;
 220#endif
 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
 226/* used on Mac OS X */
 227#ifdef PRECOMPOSE_UNICODE
 228#include "compat/precompose_utf8.h"
 229#else
 230#define precompose_str(in,i_nfd2nfc)
 231#define precompose_argv(c,v)
 232#define probe_utf8_pathname_composition()
 233#endif
 234
 235#ifdef MKDIR_WO_TRAILING_SLASH
 236#define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 237extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 238#endif
 239
 240#ifdef NO_STRUCT_ITIMERVAL
 241struct itimerval {
 242        struct timeval it_interval;
 243        struct timeval it_value;
 244};
 245#endif
 246
 247#ifdef NO_SETITIMER
 248#define setitimer(which,value,ovalue)
 249#endif
 250
 251#ifndef NO_LIBGEN_H
 252#include <libgen.h>
 253#else
 254#define basename gitbasename
 255extern char *gitbasename(char *);
 256#endif
 257
 258#ifndef NO_ICONV
 259#include <iconv.h>
 260#endif
 261
 262#ifndef NO_OPENSSL
 263#ifdef __APPLE__
 264#define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 265#include <AvailabilityMacros.h>
 266#undef DEPRECATED_ATTRIBUTE
 267#define DEPRECATED_ATTRIBUTE
 268#undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 269#endif
 270#include <openssl/ssl.h>
 271#include <openssl/err.h>
 272#ifdef NO_HMAC_CTX_CLEANUP
 273#define HMAC_CTX_cleanup HMAC_cleanup
 274#endif
 275#endif
 276
 277/* On most systems <netdb.h> would have given us this, but
 278 * not on some systems (e.g. z/OS).
 279 */
 280#ifndef NI_MAXHOST
 281#define NI_MAXHOST 1025
 282#endif
 283
 284#ifndef NI_MAXSERV
 285#define NI_MAXSERV 32
 286#endif
 287
 288/* On most systems <limits.h> would have given us this, but
 289 * not on some systems (e.g. GNU/Hurd).
 290 */
 291#ifndef PATH_MAX
 292#define PATH_MAX 4096
 293#endif
 294
 295#ifndef PRIuMAX
 296#define PRIuMAX "llu"
 297#endif
 298
 299#ifndef SCNuMAX
 300#define SCNuMAX PRIuMAX
 301#endif
 302
 303#ifndef PRIu32
 304#define PRIu32 "u"
 305#endif
 306
 307#ifndef PRIx32
 308#define PRIx32 "x"
 309#endif
 310
 311#ifndef PRIo32
 312#define PRIo32 "o"
 313#endif
 314
 315#ifndef PATH_SEP
 316#define PATH_SEP ':'
 317#endif
 318
 319#ifdef HAVE_PATHS_H
 320#include <paths.h>
 321#endif
 322#ifndef _PATH_DEFPATH
 323#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 324#endif
 325
 326#ifndef STRIP_EXTENSION
 327#define STRIP_EXTENSION ""
 328#endif
 329
 330#ifndef has_dos_drive_prefix
 331static inline int git_has_dos_drive_prefix(const char *path)
 332{
 333        return 0;
 334}
 335#define has_dos_drive_prefix git_has_dos_drive_prefix
 336#endif
 337
 338#ifndef is_dir_sep
 339static inline int git_is_dir_sep(int c)
 340{
 341        return c == '/';
 342}
 343#define is_dir_sep git_is_dir_sep
 344#endif
 345
 346#ifndef offset_1st_component
 347static inline int git_offset_1st_component(const char *path)
 348{
 349        return is_dir_sep(path[0]);
 350}
 351#define offset_1st_component git_offset_1st_component
 352#endif
 353
 354#ifndef find_last_dir_sep
 355static inline char *git_find_last_dir_sep(const char *path)
 356{
 357        return strrchr(path, '/');
 358}
 359#define find_last_dir_sep git_find_last_dir_sep
 360#endif
 361
 362#if defined(__HP_cc) && (__HP_cc >= 61000)
 363#define NORETURN __attribute__((noreturn))
 364#define NORETURN_PTR
 365#elif defined(__GNUC__) && !defined(NO_NORETURN)
 366#define NORETURN __attribute__((__noreturn__))
 367#define NORETURN_PTR __attribute__((__noreturn__))
 368#elif defined(_MSC_VER)
 369#define NORETURN __declspec(noreturn)
 370#define NORETURN_PTR
 371#else
 372#define NORETURN
 373#define NORETURN_PTR
 374#ifndef __GNUC__
 375#ifndef __attribute__
 376#define __attribute__(x)
 377#endif
 378#endif
 379#endif
 380
 381/* The sentinel attribute is valid from gcc version 4.0 */
 382#if defined(__GNUC__) && (__GNUC__ >= 4)
 383#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 384#else
 385#define LAST_ARG_MUST_BE_NULL
 386#endif
 387
 388#include "compat/bswap.h"
 389
 390#include "wildmatch.h"
 391
 392struct strbuf;
 393
 394/* General helper functions */
 395extern void vreportf(const char *prefix, const char *err, va_list params);
 396extern NORETURN void usage(const char *err);
 397extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 398extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 399extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 400extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 401extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 402
 403#ifndef NO_OPENSSL
 404#ifdef APPLE_COMMON_CRYPTO
 405#include "compat/apple-common-crypto.h"
 406#else
 407#include <openssl/evp.h>
 408#include <openssl/hmac.h>
 409#endif /* APPLE_COMMON_CRYPTO */
 410#include <openssl/x509v3.h>
 411#endif /* NO_OPENSSL */
 412
 413/*
 414 * Let callers be aware of the constant return value; this can help
 415 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 416 * because some compilers may not support variadic macros. Since we're only
 417 * trying to help gcc, anyway, it's OK; other compilers will fall back to
 418 * using the function as usual.
 419 */
 420#if defined(__GNUC__)
 421static inline int const_error(void)
 422{
 423        return -1;
 424}
 425#define error(...) (error(__VA_ARGS__), const_error())
 426#endif
 427
 428extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 429extern void set_error_routine(void (*routine)(const char *err, va_list params));
 430extern void set_die_is_recursing_routine(int (*routine)(void));
 431extern void set_error_handle(FILE *);
 432
 433extern int starts_with(const char *str, const char *prefix);
 434
 435/*
 436 * If the string "str" begins with the string found in "prefix", return 1.
 437 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 438 * the string right after the prefix).
 439 *
 440 * Otherwise, return 0 and leave "out" untouched.
 441 *
 442 * Examples:
 443 *
 444 *   [extract branch name, fail if not a branch]
 445 *   if (!skip_prefix(ref, "refs/heads/", &branch)
 446 *      return -1;
 447 *
 448 *   [skip prefix if present, otherwise use whole string]
 449 *   skip_prefix(name, "refs/heads/", &name);
 450 */
 451static inline int skip_prefix(const char *str, const char *prefix,
 452                              const char **out)
 453{
 454        do {
 455                if (!*prefix) {
 456                        *out = str;
 457                        return 1;
 458                }
 459        } while (*str++ == *prefix++);
 460        return 0;
 461}
 462
 463/*
 464 * If buf ends with suffix, return 1 and subtract the length of the suffix
 465 * from *len. Otherwise, return 0 and leave *len untouched.
 466 */
 467static inline int strip_suffix_mem(const char *buf, size_t *len,
 468                                   const char *suffix)
 469{
 470        size_t suflen = strlen(suffix);
 471        if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 472                return 0;
 473        *len -= suflen;
 474        return 1;
 475}
 476
 477/*
 478 * If str ends with suffix, return 1 and set *len to the size of the string
 479 * without the suffix. Otherwise, return 0 and set *len to the size of the
 480 * string.
 481 *
 482 * Note that we do _not_ NUL-terminate str to the new length.
 483 */
 484static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 485{
 486        *len = strlen(str);
 487        return strip_suffix_mem(str, len, suffix);
 488}
 489
 490static inline int ends_with(const char *str, const char *suffix)
 491{
 492        size_t len;
 493        return strip_suffix(str, suffix, &len);
 494}
 495
 496#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 497
 498#ifndef PROT_READ
 499#define PROT_READ 1
 500#define PROT_WRITE 2
 501#define MAP_PRIVATE 1
 502#endif
 503
 504#define mmap git_mmap
 505#define munmap git_munmap
 506extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 507extern int git_munmap(void *start, size_t length);
 508
 509#else /* NO_MMAP || USE_WIN32_MMAP */
 510
 511#include <sys/mman.h>
 512
 513#endif /* NO_MMAP || USE_WIN32_MMAP */
 514
 515#ifdef NO_MMAP
 516
 517/* This value must be multiple of (pagesize * 2) */
 518#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 519
 520#else /* NO_MMAP */
 521
 522/* This value must be multiple of (pagesize * 2) */
 523#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 524        (sizeof(void*) >= 8 \
 525                ?  1 * 1024 * 1024 * 1024 \
 526                : 32 * 1024 * 1024)
 527
 528#endif /* NO_MMAP */
 529
 530#ifndef MAP_FAILED
 531#define MAP_FAILED ((void *)-1)
 532#endif
 533
 534#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 535#define on_disk_bytes(st) ((st).st_size)
 536#else
 537#define on_disk_bytes(st) ((st).st_blocks * 512)
 538#endif
 539
 540#ifdef NEEDS_MODE_TRANSLATION
 541#undef S_IFMT
 542#undef S_IFREG
 543#undef S_IFDIR
 544#undef S_IFLNK
 545#undef S_IFBLK
 546#undef S_IFCHR
 547#undef S_IFIFO
 548#undef S_IFSOCK
 549#define S_IFMT   0170000
 550#define S_IFREG  0100000
 551#define S_IFDIR  0040000
 552#define S_IFLNK  0120000
 553#define S_IFBLK  0060000
 554#define S_IFCHR  0020000
 555#define S_IFIFO  0010000
 556#define S_IFSOCK 0140000
 557#ifdef stat
 558#undef stat
 559#endif
 560#define stat(path, buf) git_stat(path, buf)
 561extern int git_stat(const char *, struct stat *);
 562#ifdef fstat
 563#undef fstat
 564#endif
 565#define fstat(fd, buf) git_fstat(fd, buf)
 566extern int git_fstat(int, struct stat *);
 567#ifdef lstat
 568#undef lstat
 569#endif
 570#define lstat(path, buf) git_lstat(path, buf)
 571extern int git_lstat(const char *, struct stat *);
 572#endif
 573
 574#define DEFAULT_PACKED_GIT_LIMIT \
 575        ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? 8192 : 256))
 576
 577#ifdef NO_PREAD
 578#define pread git_pread
 579extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 580#endif
 581/*
 582 * Forward decl that will remind us if its twin in cache.h changes.
 583 * This function is used in compat/pread.c.  But we can't include
 584 * cache.h there.
 585 */
 586extern ssize_t read_in_full(int fd, void *buf, size_t count);
 587
 588#ifdef NO_SETENV
 589#define setenv gitsetenv
 590extern int gitsetenv(const char *, const char *, int);
 591#endif
 592
 593#ifdef NO_MKDTEMP
 594#define mkdtemp gitmkdtemp
 595extern char *gitmkdtemp(char *);
 596#endif
 597
 598#ifdef NO_MKSTEMPS
 599#define mkstemps gitmkstemps
 600extern int gitmkstemps(char *, int);
 601#endif
 602
 603#ifdef NO_UNSETENV
 604#define unsetenv gitunsetenv
 605extern void gitunsetenv(const char *);
 606#endif
 607
 608#ifdef NO_STRCASESTR
 609#define strcasestr gitstrcasestr
 610extern char *gitstrcasestr(const char *haystack, const char *needle);
 611#endif
 612
 613#ifdef NO_STRLCPY
 614#define strlcpy gitstrlcpy
 615extern size_t gitstrlcpy(char *, const char *, size_t);
 616#endif
 617
 618#ifdef NO_STRTOUMAX
 619#define strtoumax gitstrtoumax
 620extern uintmax_t gitstrtoumax(const char *, char **, int);
 621#define strtoimax gitstrtoimax
 622extern intmax_t gitstrtoimax(const char *, char **, int);
 623#endif
 624
 625#ifdef NO_HSTRERROR
 626#define hstrerror githstrerror
 627extern const char *githstrerror(int herror);
 628#endif
 629
 630#ifdef NO_MEMMEM
 631#define memmem gitmemmem
 632void *gitmemmem(const void *haystack, size_t haystacklen,
 633                const void *needle, size_t needlelen);
 634#endif
 635
 636#ifdef NO_GETPAGESIZE
 637#define getpagesize() sysconf(_SC_PAGESIZE)
 638#endif
 639
 640#ifdef FREAD_READS_DIRECTORIES
 641#ifdef fopen
 642#undef fopen
 643#endif
 644#define fopen(a,b) git_fopen(a,b)
 645extern FILE *git_fopen(const char*, const char*);
 646#endif
 647
 648#ifdef SNPRINTF_RETURNS_BOGUS
 649#ifdef snprintf
 650#undef snprintf
 651#endif
 652#define snprintf git_snprintf
 653extern int git_snprintf(char *str, size_t maxsize,
 654                        const char *format, ...);
 655#ifdef vsnprintf
 656#undef vsnprintf
 657#endif
 658#define vsnprintf git_vsnprintf
 659extern int git_vsnprintf(char *str, size_t maxsize,
 660                         const char *format, va_list ap);
 661#endif
 662
 663#ifdef __GLIBC_PREREQ
 664#if __GLIBC_PREREQ(2, 1)
 665#define HAVE_STRCHRNUL
 666#define HAVE_MEMPCPY
 667#endif
 668#endif
 669
 670#ifndef HAVE_STRCHRNUL
 671#define strchrnul gitstrchrnul
 672static inline char *gitstrchrnul(const char *s, int c)
 673{
 674        while (*s && *s != c)
 675                s++;
 676        return (char *)s;
 677}
 678#endif
 679
 680#ifndef HAVE_MEMPCPY
 681#define mempcpy gitmempcpy
 682static inline void *gitmempcpy(void *dest, const void *src, size_t n)
 683{
 684        return (char *)memcpy(dest, src, n) + n;
 685}
 686#endif
 687
 688#ifdef NO_INET_PTON
 689int inet_pton(int af, const char *src, void *dst);
 690#endif
 691
 692#ifdef NO_INET_NTOP
 693const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 694#endif
 695
 696#ifdef NO_PTHREADS
 697#define atexit git_atexit
 698extern int git_atexit(void (*handler)(void));
 699#endif
 700
 701extern void release_pack_memory(size_t);
 702
 703typedef void (*try_to_free_t)(size_t);
 704extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 705
 706#ifdef HAVE_ALLOCA_H
 707# include <alloca.h>
 708# define xalloca(size)      (alloca(size))
 709# define xalloca_free(p)    do {} while (0)
 710#else
 711# define xalloca(size)      (xmalloc(size))
 712# define xalloca_free(p)    (free(p))
 713#endif
 714extern char *xstrdup(const char *str);
 715extern void *xmalloc(size_t size);
 716extern void *xmallocz(size_t size);
 717extern void *xmallocz_gently(size_t size);
 718extern void *xmemdupz(const void *data, size_t len);
 719extern char *xstrndup(const char *str, size_t len);
 720extern void *xrealloc(void *ptr, size_t size);
 721extern void *xcalloc(size_t nmemb, size_t size);
 722extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 723extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 724extern int xopen(const char *path, int flags, ...);
 725extern ssize_t xread(int fd, void *buf, size_t len);
 726extern ssize_t xwrite(int fd, const void *buf, size_t len);
 727extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 728extern int xdup(int fd);
 729extern FILE *xfopen(const char *path, const char *mode);
 730extern FILE *xfdopen(int fd, const char *mode);
 731extern int xmkstemp(char *template);
 732extern int xmkstemp_mode(char *template, int mode);
 733extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
 734extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
 735extern char *xgetcwd(void);
 736
 737#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), (alloc) * sizeof(*(x)))
 738
 739static inline char *xstrdup_or_null(const char *str)
 740{
 741        return str ? xstrdup(str) : NULL;
 742}
 743
 744static inline size_t xsize_t(off_t len)
 745{
 746        if (len > (size_t) len)
 747                die("Cannot handle files this big");
 748        return (size_t)len;
 749}
 750
 751__attribute__((format (printf, 3, 4)))
 752extern int xsnprintf(char *dst, size_t max, const char *fmt, ...);
 753
 754/* in ctype.c, for kwset users */
 755extern const unsigned char tolower_trans_tbl[256];
 756
 757/* Sane ctype - no locale, and works with signed chars */
 758#undef isascii
 759#undef isspace
 760#undef isdigit
 761#undef isalpha
 762#undef isalnum
 763#undef isprint
 764#undef islower
 765#undef isupper
 766#undef tolower
 767#undef toupper
 768#undef iscntrl
 769#undef ispunct
 770#undef isxdigit
 771
 772extern const unsigned char sane_ctype[256];
 773#define GIT_SPACE 0x01
 774#define GIT_DIGIT 0x02
 775#define GIT_ALPHA 0x04
 776#define GIT_GLOB_SPECIAL 0x08
 777#define GIT_REGEX_SPECIAL 0x10
 778#define GIT_PATHSPEC_MAGIC 0x20
 779#define GIT_CNTRL 0x40
 780#define GIT_PUNCT 0x80
 781#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 782#define isascii(x) (((x) & ~0x7f) == 0)
 783#define isspace(x) sane_istest(x,GIT_SPACE)
 784#define isdigit(x) sane_istest(x,GIT_DIGIT)
 785#define isalpha(x) sane_istest(x,GIT_ALPHA)
 786#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 787#define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 788#define islower(x) sane_iscase(x, 1)
 789#define isupper(x) sane_iscase(x, 0)
 790#define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 791#define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 792#define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 793#define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 794                GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 795#define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 796#define tolower(x) sane_case((unsigned char)(x), 0x20)
 797#define toupper(x) sane_case((unsigned char)(x), 0)
 798#define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 799
 800static inline int sane_case(int x, int high)
 801{
 802        if (sane_istest(x, GIT_ALPHA))
 803                x = (x & ~0x20) | high;
 804        return x;
 805}
 806
 807static inline int sane_iscase(int x, int is_lower)
 808{
 809        if (!sane_istest(x, GIT_ALPHA))
 810                return 0;
 811
 812        if (is_lower)
 813                return (x & 0x20) != 0;
 814        else
 815                return (x & 0x20) == 0;
 816}
 817
 818static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 819{
 820        unsigned long ul;
 821        char *p;
 822
 823        errno = 0;
 824        /* negative values would be accepted by strtoul */
 825        if (strchr(s, '-'))
 826                return -1;
 827        ul = strtoul(s, &p, base);
 828        if (errno || *p || p == s || (unsigned int) ul != ul)
 829                return -1;
 830        *result = ul;
 831        return 0;
 832}
 833
 834static inline int strtol_i(char const *s, int base, int *result)
 835{
 836        long ul;
 837        char *p;
 838
 839        errno = 0;
 840        ul = strtol(s, &p, base);
 841        if (errno || *p || p == s || (int) ul != ul)
 842                return -1;
 843        *result = ul;
 844        return 0;
 845}
 846
 847#ifdef INTERNAL_QSORT
 848void git_qsort(void *base, size_t nmemb, size_t size,
 849               int(*compar)(const void *, const void *));
 850#define qsort git_qsort
 851#endif
 852
 853#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
 854# define FORCE_DIR_SET_GID S_ISGID
 855#else
 856# define FORCE_DIR_SET_GID 0
 857#endif
 858
 859#ifdef NO_NSEC
 860#undef USE_NSEC
 861#define ST_CTIME_NSEC(st) 0
 862#define ST_MTIME_NSEC(st) 0
 863#else
 864#ifdef USE_ST_TIMESPEC
 865#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
 866#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
 867#else
 868#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
 869#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
 870#endif
 871#endif
 872
 873#ifdef UNRELIABLE_FSTAT
 874#define fstat_is_reliable() 0
 875#else
 876#define fstat_is_reliable() 1
 877#endif
 878
 879#ifndef va_copy
 880/*
 881 * Since an obvious implementation of va_list would be to make it a
 882 * pointer into the stack frame, a simple assignment will work on
 883 * many systems.  But let's try to be more portable.
 884 */
 885#ifdef __va_copy
 886#define va_copy(dst, src) __va_copy(dst, src)
 887#else
 888#define va_copy(dst, src) ((dst) = (src))
 889#endif
 890#endif
 891
 892#if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
 893#define HAVE_VARIADIC_MACROS 1
 894#endif
 895
 896/*
 897 * Preserves errno, prints a message, but gives no warning for ENOENT.
 898 * Returns 0 on success, which includes trying to unlink an object that does
 899 * not exist.
 900 */
 901int unlink_or_warn(const char *path);
 902 /*
 903  * Tries to unlink file.  Returns 0 if unlink succeeded
 904  * or the file already didn't exist.  Returns -1 and
 905  * appends a message to err suitable for
 906  * 'error("%s", err->buf)' on error.
 907  */
 908int unlink_or_msg(const char *file, struct strbuf *err);
 909/*
 910 * Preserves errno, prints a message, but gives no warning for ENOENT.
 911 * Returns 0 on success, which includes trying to remove a directory that does
 912 * not exist.
 913 */
 914int rmdir_or_warn(const char *path);
 915/*
 916 * Calls the correct function out of {unlink,rmdir}_or_warn based on
 917 * the supplied file mode.
 918 */
 919int remove_or_warn(unsigned int mode, const char *path);
 920
 921/*
 922 * Call access(2), but warn for any error except "missing file"
 923 * (ENOENT or ENOTDIR).
 924 */
 925#define ACCESS_EACCES_OK (1U << 0)
 926int access_or_warn(const char *path, int mode, unsigned flag);
 927int access_or_die(const char *path, int mode, unsigned flag);
 928
 929/* Warn on an inaccessible file that ought to be accessible */
 930void warn_on_inaccessible(const char *path);
 931
 932#ifdef GMTIME_UNRELIABLE_ERRORS
 933struct tm *git_gmtime(const time_t *);
 934struct tm *git_gmtime_r(const time_t *, struct tm *);
 935#define gmtime git_gmtime
 936#define gmtime_r git_gmtime_r
 937#endif
 938
 939#if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
 940#define USE_PARENS_AROUND_GETTEXT_N 1
 941#endif
 942
 943#ifndef SHELL_PATH
 944# define SHELL_PATH "/bin/sh"
 945#endif
 946
 947#ifndef _POSIX_THREAD_SAFE_FUNCTIONS
 948#define flockfile(fh)
 949#define funlockfile(fh)
 950#define getc_unlocked(fh) getc(fh)
 951#endif
 952
 953#endif