Andrew's git / gitweb.git / git-compat-util.h
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git-compat-util.hon commit apply: make it possible to silently apply (a46160d)
   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 */
 226typedef long intptr_t;
 227typedef 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))
 245extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 246#endif
 247
 248#ifdef NO_STRUCT_ITIMERVAL
 249struct 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
 263extern char *gitbasename(char *);
 264#define dirname gitdirname
 265extern 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#ifndef PATH_SEP
 323#define PATH_SEP ':'
 324#endif
 325
 326#ifdef HAVE_PATHS_H
 327#include <paths.h>
 328#endif
 329#ifndef _PATH_DEFPATH
 330#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 331#endif
 332
 333#ifndef has_dos_drive_prefix
 334static inline int git_has_dos_drive_prefix(const char *path)
 335{
 336        return 0;
 337}
 338#define has_dos_drive_prefix git_has_dos_drive_prefix
 339#endif
 340
 341#ifndef skip_dos_drive_prefix
 342static inline int git_skip_dos_drive_prefix(char **path)
 343{
 344        return 0;
 345}
 346#define skip_dos_drive_prefix git_skip_dos_drive_prefix
 347#endif
 348
 349#ifndef is_dir_sep
 350static inline int git_is_dir_sep(int c)
 351{
 352        return c == '/';
 353}
 354#define is_dir_sep git_is_dir_sep
 355#endif
 356
 357#ifndef offset_1st_component
 358static inline int git_offset_1st_component(const char *path)
 359{
 360        return is_dir_sep(path[0]);
 361}
 362#define offset_1st_component git_offset_1st_component
 363#endif
 364
 365#ifndef find_last_dir_sep
 366static inline char *git_find_last_dir_sep(const char *path)
 367{
 368        return strrchr(path, '/');
 369}
 370#define find_last_dir_sep git_find_last_dir_sep
 371#endif
 372
 373#if defined(__HP_cc) && (__HP_cc >= 61000)
 374#define NORETURN __attribute__((noreturn))
 375#define NORETURN_PTR
 376#elif defined(__GNUC__) && !defined(NO_NORETURN)
 377#define NORETURN __attribute__((__noreturn__))
 378#define NORETURN_PTR __attribute__((__noreturn__))
 379#elif defined(_MSC_VER)
 380#define NORETURN __declspec(noreturn)
 381#define NORETURN_PTR
 382#else
 383#define NORETURN
 384#define NORETURN_PTR
 385#ifndef __GNUC__
 386#ifndef __attribute__
 387#define __attribute__(x)
 388#endif
 389#endif
 390#endif
 391
 392/* The sentinel attribute is valid from gcc version 4.0 */
 393#if defined(__GNUC__) && (__GNUC__ >= 4)
 394#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 395#else
 396#define LAST_ARG_MUST_BE_NULL
 397#endif
 398
 399#include "compat/bswap.h"
 400
 401#include "wildmatch.h"
 402
 403struct strbuf;
 404
 405/* General helper functions */
 406extern void vreportf(const char *prefix, const char *err, va_list params);
 407extern NORETURN void usage(const char *err);
 408extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 409extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 410extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 411extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 412extern int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 413extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 414extern void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 415
 416#ifndef NO_OPENSSL
 417#ifdef APPLE_COMMON_CRYPTO
 418#include "compat/apple-common-crypto.h"
 419#else
 420#include <openssl/evp.h>
 421#include <openssl/hmac.h>
 422#endif /* APPLE_COMMON_CRYPTO */
 423#include <openssl/x509v3.h>
 424#endif /* NO_OPENSSL */
 425
 426/*
 427 * Let callers be aware of the constant return value; this can help
 428 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 429 * because some compilers may not support variadic macros. Since we're only
 430 * trying to help gcc, anyway, it's OK; other compilers will fall back to
 431 * using the function as usual.
 432 */
 433#if defined(__GNUC__)
 434static inline int const_error(void)
 435{
 436        return -1;
 437}
 438#define error(...) (error(__VA_ARGS__), const_error())
 439#endif
 440
 441extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 442extern void set_error_routine(void (*routine)(const char *err, va_list params));
 443extern void set_die_is_recursing_routine(int (*routine)(void));
 444extern void set_error_handle(FILE *);
 445
 446extern int starts_with(const char *str, const char *prefix);
 447
 448/*
 449 * If the string "str" begins with the string found in "prefix", return 1.
 450 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 451 * the string right after the prefix).
 452 *
 453 * Otherwise, return 0 and leave "out" untouched.
 454 *
 455 * Examples:
 456 *
 457 *   [extract branch name, fail if not a branch]
 458 *   if (!skip_prefix(ref, "refs/heads/", &branch)
 459 *      return -1;
 460 *
 461 *   [skip prefix if present, otherwise use whole string]
 462 *   skip_prefix(name, "refs/heads/", &name);
 463 */
 464static inline int skip_prefix(const char *str, const char *prefix,
 465                              const char **out)
 466{
 467        do {
 468                if (!*prefix) {
 469                        *out = str;
 470                        return 1;
 471                }
 472        } while (*str++ == *prefix++);
 473        return 0;
 474}
 475
 476/*
 477 * Like skip_prefix, but promises never to read past "len" bytes of the input
 478 * buffer, and returns the remaining number of bytes in "out" via "outlen".
 479 */
 480static inline int skip_prefix_mem(const char *buf, size_t len,
 481                                  const char *prefix,
 482                                  const char **out, size_t *outlen)
 483{
 484        size_t prefix_len = strlen(prefix);
 485        if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 486                *out = buf + prefix_len;
 487                *outlen = len - prefix_len;
 488                return 1;
 489        }
 490        return 0;
 491}
 492
 493/*
 494 * If buf ends with suffix, return 1 and subtract the length of the suffix
 495 * from *len. Otherwise, return 0 and leave *len untouched.
 496 */
 497static inline int strip_suffix_mem(const char *buf, size_t *len,
 498                                   const char *suffix)
 499{
 500        size_t suflen = strlen(suffix);
 501        if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 502                return 0;
 503        *len -= suflen;
 504        return 1;
 505}
 506
 507/*
 508 * If str ends with suffix, return 1 and set *len to the size of the string
 509 * without the suffix. Otherwise, return 0 and set *len to the size of the
 510 * string.
 511 *
 512 * Note that we do _not_ NUL-terminate str to the new length.
 513 */
 514static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 515{
 516        *len = strlen(str);
 517        return strip_suffix_mem(str, len, suffix);
 518}
 519
 520static inline int ends_with(const char *str, const char *suffix)
 521{
 522        size_t len;
 523        return strip_suffix(str, suffix, &len);
 524}
 525
 526#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 527
 528#ifndef PROT_READ
 529#define PROT_READ 1
 530#define PROT_WRITE 2
 531#define MAP_PRIVATE 1
 532#endif
 533
 534#define mmap git_mmap
 535#define munmap git_munmap
 536extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 537extern int git_munmap(void *start, size_t length);
 538
 539#else /* NO_MMAP || USE_WIN32_MMAP */
 540
 541#include <sys/mman.h>
 542
 543#endif /* NO_MMAP || USE_WIN32_MMAP */
 544
 545#ifdef NO_MMAP
 546
 547/* This value must be multiple of (pagesize * 2) */
 548#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 549
 550#else /* NO_MMAP */
 551
 552/* This value must be multiple of (pagesize * 2) */
 553#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 554        (sizeof(void*) >= 8 \
 555                ?  1 * 1024 * 1024 * 1024 \
 556                : 32 * 1024 * 1024)
 557
 558#endif /* NO_MMAP */
 559
 560#ifndef MAP_FAILED
 561#define MAP_FAILED ((void *)-1)
 562#endif
 563
 564#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 565#define on_disk_bytes(st) ((st).st_size)
 566#else
 567#define on_disk_bytes(st) ((st).st_blocks * 512)
 568#endif
 569
 570#ifdef NEEDS_MODE_TRANSLATION
 571#undef S_IFMT
 572#undef S_IFREG
 573#undef S_IFDIR
 574#undef S_IFLNK
 575#undef S_IFBLK
 576#undef S_IFCHR
 577#undef S_IFIFO
 578#undef S_IFSOCK
 579#define S_IFMT   0170000
 580#define S_IFREG  0100000
 581#define S_IFDIR  0040000
 582#define S_IFLNK  0120000
 583#define S_IFBLK  0060000
 584#define S_IFCHR  0020000
 585#define S_IFIFO  0010000
 586#define S_IFSOCK 0140000
 587#ifdef stat
 588#undef stat
 589#endif
 590#define stat(path, buf) git_stat(path, buf)
 591extern int git_stat(const char *, struct stat *);
 592#ifdef fstat
 593#undef fstat
 594#endif
 595#define fstat(fd, buf) git_fstat(fd, buf)
 596extern int git_fstat(int, struct stat *);
 597#ifdef lstat
 598#undef lstat
 599#endif
 600#define lstat(path, buf) git_lstat(path, buf)
 601extern int git_lstat(const char *, struct stat *);
 602#endif
 603
 604#define DEFAULT_PACKED_GIT_LIMIT \
 605        ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? 8192 : 256))
 606
 607#ifdef NO_PREAD
 608#define pread git_pread
 609extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 610#endif
 611/*
 612 * Forward decl that will remind us if its twin in cache.h changes.
 613 * This function is used in compat/pread.c.  But we can't include
 614 * cache.h there.
 615 */
 616extern ssize_t read_in_full(int fd, void *buf, size_t count);
 617
 618#ifdef NO_SETENV
 619#define setenv gitsetenv
 620extern int gitsetenv(const char *, const char *, int);
 621#endif
 622
 623#ifdef NO_MKDTEMP
 624#define mkdtemp gitmkdtemp
 625extern char *gitmkdtemp(char *);
 626#endif
 627
 628#ifdef NO_MKSTEMPS
 629#define mkstemps gitmkstemps
 630extern int gitmkstemps(char *, int);
 631#endif
 632
 633#ifdef NO_UNSETENV
 634#define unsetenv gitunsetenv
 635extern void gitunsetenv(const char *);
 636#endif
 637
 638#ifdef NO_STRCASESTR
 639#define strcasestr gitstrcasestr
 640extern char *gitstrcasestr(const char *haystack, const char *needle);
 641#endif
 642
 643#ifdef NO_STRLCPY
 644#define strlcpy gitstrlcpy
 645extern size_t gitstrlcpy(char *, const char *, size_t);
 646#endif
 647
 648#ifdef NO_STRTOUMAX
 649#define strtoumax gitstrtoumax
 650extern uintmax_t gitstrtoumax(const char *, char **, int);
 651#define strtoimax gitstrtoimax
 652extern intmax_t gitstrtoimax(const char *, char **, int);
 653#endif
 654
 655#ifdef NO_HSTRERROR
 656#define hstrerror githstrerror
 657extern const char *githstrerror(int herror);
 658#endif
 659
 660#ifdef NO_MEMMEM
 661#define memmem gitmemmem
 662void *gitmemmem(const void *haystack, size_t haystacklen,
 663                const void *needle, size_t needlelen);
 664#endif
 665
 666#ifdef NO_GETPAGESIZE
 667#define getpagesize() sysconf(_SC_PAGESIZE)
 668#endif
 669
 670#ifdef FREAD_READS_DIRECTORIES
 671#ifdef fopen
 672#undef fopen
 673#endif
 674#define fopen(a,b) git_fopen(a,b)
 675extern FILE *git_fopen(const char*, const char*);
 676#endif
 677
 678#ifdef SNPRINTF_RETURNS_BOGUS
 679#ifdef snprintf
 680#undef snprintf
 681#endif
 682#define snprintf git_snprintf
 683extern int git_snprintf(char *str, size_t maxsize,
 684                        const char *format, ...);
 685#ifdef vsnprintf
 686#undef vsnprintf
 687#endif
 688#define vsnprintf git_vsnprintf
 689extern int git_vsnprintf(char *str, size_t maxsize,
 690                         const char *format, va_list ap);
 691#endif
 692
 693#ifdef __GLIBC_PREREQ
 694#if __GLIBC_PREREQ(2, 1)
 695#define HAVE_STRCHRNUL
 696#endif
 697#endif
 698
 699#ifndef HAVE_STRCHRNUL
 700#define strchrnul gitstrchrnul
 701static inline char *gitstrchrnul(const char *s, int c)
 702{
 703        while (*s && *s != c)
 704                s++;
 705        return (char *)s;
 706}
 707#endif
 708
 709#ifdef NO_INET_PTON
 710int inet_pton(int af, const char *src, void *dst);
 711#endif
 712
 713#ifdef NO_INET_NTOP
 714const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 715#endif
 716
 717#ifdef NO_PTHREADS
 718#define atexit git_atexit
 719extern int git_atexit(void (*handler)(void));
 720#endif
 721
 722extern void release_pack_memory(size_t);
 723
 724typedef void (*try_to_free_t)(size_t);
 725extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 726
 727static inline size_t st_add(size_t a, size_t b)
 728{
 729        if (unsigned_add_overflows(a, b))
 730                die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 731                    (uintmax_t)a, (uintmax_t)b);
 732        return a + b;
 733}
 734#define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 735#define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 736
 737static inline size_t st_mult(size_t a, size_t b)
 738{
 739        if (unsigned_mult_overflows(a, b))
 740                die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 741                    (uintmax_t)a, (uintmax_t)b);
 742        return a * b;
 743}
 744
 745static inline size_t st_sub(size_t a, size_t b)
 746{
 747        if (a < b)
 748                die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 749                    (uintmax_t)a, (uintmax_t)b);
 750        return a - b;
 751}
 752
 753#ifdef HAVE_ALLOCA_H
 754# include <alloca.h>
 755# define xalloca(size)      (alloca(size))
 756# define xalloca_free(p)    do {} while (0)
 757#else
 758# define xalloca(size)      (xmalloc(size))
 759# define xalloca_free(p)    (free(p))
 760#endif
 761extern char *xstrdup(const char *str);
 762extern void *xmalloc(size_t size);
 763extern void *xmallocz(size_t size);
 764extern void *xmallocz_gently(size_t size);
 765extern void *xmemdupz(const void *data, size_t len);
 766extern char *xstrndup(const char *str, size_t len);
 767extern void *xrealloc(void *ptr, size_t size);
 768extern void *xcalloc(size_t nmemb, size_t size);
 769extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 770extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 771extern int xopen(const char *path, int flags, ...);
 772extern ssize_t xread(int fd, void *buf, size_t len);
 773extern ssize_t xwrite(int fd, const void *buf, size_t len);
 774extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 775extern int xdup(int fd);
 776extern FILE *xfopen(const char *path, const char *mode);
 777extern FILE *xfdopen(int fd, const char *mode);
 778extern int xmkstemp(char *template);
 779extern int xmkstemp_mode(char *template, int mode);
 780extern int odb_mkstemp(char *template, size_t limit, const char *pattern);
 781extern int odb_pack_keep(char *name, size_t namesz, const unsigned char *sha1);
 782extern char *xgetcwd(void);
 783extern FILE *fopen_for_writing(const char *path);
 784
 785#define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 786#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 787
 788/*
 789 * These functions help you allocate structs with flex arrays, and copy
 790 * the data directly into the array. For example, if you had:
 791 *
 792 *   struct foo {
 793 *     int bar;
 794 *     char name[FLEX_ARRAY];
 795 *   };
 796 *
 797 * you can do:
 798 *
 799 *   struct foo *f;
 800 *   FLEX_ALLOC_MEM(f, name, src, len);
 801 *
 802 * to allocate a "foo" with the contents of "src" in the "name" field.
 803 * The resulting struct is automatically zero'd, and the flex-array field
 804 * is NUL-terminated (whether the incoming src buffer was or not).
 805 *
 806 * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
 807 * but do want to store a pointer to some extra data in the same allocated
 808 * block. For example, if you have:
 809 *
 810 *   struct foo {
 811 *     char *name;
 812 *     int bar;
 813 *   };
 814 *
 815 * you can do:
 816 *
 817 *   struct foo *f;
 818 *   FLEX_ALLOC_STR(f, name, src);
 819 *
 820 * and "name" will point to a block of memory after the struct, which will be
 821 * freed along with the struct (but the pointer can be repointed anywhere).
 822 *
 823 * The *_STR variants accept a string parameter rather than a ptr/len
 824 * combination.
 825 *
 826 * Note that these macros will evaluate the first parameter multiple
 827 * times, and it must be assignable as an lvalue.
 828 */
 829#define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
 830        (x) = NULL; /* silence -Wuninitialized for offset calculation */ \
 831        (x) = xalloc_flex(sizeof(*(x)), (char *)(&((x)->flexname)) - (char *)(x), (buf), (len)); \
 832} while (0)
 833#define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
 834        (x) = xalloc_flex(sizeof(*(x)), sizeof(*(x)), (buf), (len)); \
 835        (x)->ptrname = (void *)((x)+1); \
 836} while(0)
 837#define FLEX_ALLOC_STR(x, flexname, str) \
 838        FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
 839#define FLEXPTR_ALLOC_STR(x, ptrname, str) \
 840        FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
 841
 842static inline void *xalloc_flex(size_t base_len, size_t offset,
 843                                const void *src, size_t src_len)
 844{
 845        unsigned char *ret = xcalloc(1, st_add3(base_len, src_len, 1));
 846        memcpy(ret + offset, src, src_len);
 847        return ret;
 848}
 849
 850static inline char *xstrdup_or_null(const char *str)
 851{
 852        return str ? xstrdup(str) : NULL;
 853}
 854
 855static inline size_t xsize_t(off_t len)
 856{
 857        if (len > (size_t) len)
 858                die("Cannot handle files this big");
 859        return (size_t)len;
 860}
 861
 862__attribute__((format (printf, 3, 4)))
 863extern int xsnprintf(char *dst, size_t max, const char *fmt, ...);
 864
 865/* in ctype.c, for kwset users */
 866extern const unsigned char tolower_trans_tbl[256];
 867
 868/* Sane ctype - no locale, and works with signed chars */
 869#undef isascii
 870#undef isspace
 871#undef isdigit
 872#undef isalpha
 873#undef isalnum
 874#undef isprint
 875#undef islower
 876#undef isupper
 877#undef tolower
 878#undef toupper
 879#undef iscntrl
 880#undef ispunct
 881#undef isxdigit
 882
 883extern const unsigned char sane_ctype[256];
 884#define GIT_SPACE 0x01
 885#define GIT_DIGIT 0x02
 886#define GIT_ALPHA 0x04
 887#define GIT_GLOB_SPECIAL 0x08
 888#define GIT_REGEX_SPECIAL 0x10
 889#define GIT_PATHSPEC_MAGIC 0x20
 890#define GIT_CNTRL 0x40
 891#define GIT_PUNCT 0x80
 892#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 893#define isascii(x) (((x) & ~0x7f) == 0)
 894#define isspace(x) sane_istest(x,GIT_SPACE)
 895#define isdigit(x) sane_istest(x,GIT_DIGIT)
 896#define isalpha(x) sane_istest(x,GIT_ALPHA)
 897#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 898#define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 899#define islower(x) sane_iscase(x, 1)
 900#define isupper(x) sane_iscase(x, 0)
 901#define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 902#define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 903#define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 904#define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 905                GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 906#define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 907#define tolower(x) sane_case((unsigned char)(x), 0x20)
 908#define toupper(x) sane_case((unsigned char)(x), 0)
 909#define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 910
 911static inline int sane_case(int x, int high)
 912{
 913        if (sane_istest(x, GIT_ALPHA))
 914                x = (x & ~0x20) | high;
 915        return x;
 916}
 917
 918static inline int sane_iscase(int x, int is_lower)
 919{
 920        if (!sane_istest(x, GIT_ALPHA))
 921                return 0;
 922
 923        if (is_lower)
 924                return (x & 0x20) != 0;
 925        else
 926                return (x & 0x20) == 0;
 927}
 928
 929static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 930{
 931        unsigned long ul;
 932        char *p;
 933
 934        errno = 0;
 935        /* negative values would be accepted by strtoul */
 936        if (strchr(s, '-'))
 937                return -1;
 938        ul = strtoul(s, &p, base);
 939        if (errno || *p || p == s || (unsigned int) ul != ul)
 940                return -1;
 941        *result = ul;
 942        return 0;
 943}
 944
 945static inline int strtol_i(char const *s, int base, int *result)
 946{
 947        long ul;
 948        char *p;
 949
 950        errno = 0;
 951        ul = strtol(s, &p, base);
 952        if (errno || *p || p == s || (int) ul != ul)
 953                return -1;
 954        *result = ul;
 955        return 0;
 956}
 957
 958#ifdef INTERNAL_QSORT
 959void git_qsort(void *base, size_t nmemb, size_t size,
 960               int(*compar)(const void *, const void *));
 961#define qsort git_qsort
 962#endif
 963
 964#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
 965# define FORCE_DIR_SET_GID S_ISGID
 966#else
 967# define FORCE_DIR_SET_GID 0
 968#endif
 969
 970#ifdef NO_NSEC
 971#undef USE_NSEC
 972#define ST_CTIME_NSEC(st) 0
 973#define ST_MTIME_NSEC(st) 0
 974#else
 975#ifdef USE_ST_TIMESPEC
 976#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
 977#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
 978#else
 979#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
 980#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
 981#endif
 982#endif
 983
 984#ifdef UNRELIABLE_FSTAT
 985#define fstat_is_reliable() 0
 986#else
 987#define fstat_is_reliable() 1
 988#endif
 989
 990#ifndef va_copy
 991/*
 992 * Since an obvious implementation of va_list would be to make it a
 993 * pointer into the stack frame, a simple assignment will work on
 994 * many systems.  But let's try to be more portable.
 995 */
 996#ifdef __va_copy
 997#define va_copy(dst, src) __va_copy(dst, src)
 998#else
 999#define va_copy(dst, src) ((dst) = (src))
1000#endif
1001#endif
1002
1003#if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
1004#define HAVE_VARIADIC_MACROS 1
1005#endif
1006
1007/*
1008 * Preserves errno, prints a message, but gives no warning for ENOENT.
1009 * Returns 0 on success, which includes trying to unlink an object that does
1010 * not exist.
1011 */
1012int unlink_or_warn(const char *path);
1013 /*
1014  * Tries to unlink file.  Returns 0 if unlink succeeded
1015  * or the file already didn't exist.  Returns -1 and
1016  * appends a message to err suitable for
1017  * 'error("%s", err->buf)' on error.
1018  */
1019int unlink_or_msg(const char *file, struct strbuf *err);
1020/*
1021 * Preserves errno, prints a message, but gives no warning for ENOENT.
1022 * Returns 0 on success, which includes trying to remove a directory that does
1023 * not exist.
1024 */
1025int rmdir_or_warn(const char *path);
1026/*
1027 * Calls the correct function out of {unlink,rmdir}_or_warn based on
1028 * the supplied file mode.
1029 */
1030int remove_or_warn(unsigned int mode, const char *path);
1031
1032/*
1033 * Call access(2), but warn for any error except "missing file"
1034 * (ENOENT or ENOTDIR).
1035 */
1036#define ACCESS_EACCES_OK (1U << 0)
1037int access_or_warn(const char *path, int mode, unsigned flag);
1038int access_or_die(const char *path, int mode, unsigned flag);
1039
1040/* Warn on an inaccessible file that ought to be accessible */
1041void warn_on_inaccessible(const char *path);
1042
1043#ifdef GMTIME_UNRELIABLE_ERRORS
1044struct tm *git_gmtime(const time_t *);
1045struct tm *git_gmtime_r(const time_t *, struct tm *);
1046#define gmtime git_gmtime
1047#define gmtime_r git_gmtime_r
1048#endif
1049
1050#if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1051#define USE_PARENS_AROUND_GETTEXT_N 1
1052#endif
1053
1054#ifndef SHELL_PATH
1055# define SHELL_PATH "/bin/sh"
1056#endif
1057
1058#ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1059#define flockfile(fh)
1060#define funlockfile(fh)
1061#define getc_unlocked(fh) getc(fh)
1062#endif
1063
1064#endif
1065
1066extern int cmd_main(int, const char **);