Andrew's git / gitweb.git / git-compat-util.h
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git-compat-util.hon commit Merge branch 'po/read-graft-line' into next (1e3fe0d)
   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(__CYGWIN__)
 193#include "compat/cygwin.h"
 194#endif
 195#if defined(__MINGW32__)
 196/* pull in Windows compatibility stuff */
 197#include "compat/mingw.h"
 198#elif defined(_MSC_VER)
 199#include "compat/msvc.h"
 200#else
 201#include <sys/utsname.h>
 202#include <sys/wait.h>
 203#include <sys/resource.h>
 204#include <sys/socket.h>
 205#include <sys/ioctl.h>
 206#include <termios.h>
 207#ifndef NO_SYS_SELECT_H
 208#include <sys/select.h>
 209#endif
 210#include <netinet/in.h>
 211#include <netinet/tcp.h>
 212#include <arpa/inet.h>
 213#include <netdb.h>
 214#include <pwd.h>
 215#include <sys/un.h>
 216#ifndef NO_INTTYPES_H
 217#include <inttypes.h>
 218#else
 219#include <stdint.h>
 220#endif
 221#ifdef NO_INTPTR_T
 222/*
 223 * On I16LP32, ILP32 and LP64 "long" is the save bet, however
 224 * on LLP86, IL33LLP64 and P64 it needs to be "long long",
 225 * while on IP16 and IP16L32 it is "int" (resp. "short")
 226 * Size needs to match (or exceed) 'sizeof(void *)'.
 227 * We can't take "long long" here as not everybody has it.
 228 */
 229typedef long intptr_t;
 230typedef unsigned long uintptr_t;
 231#endif
 232#undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
 233#include <grp.h>
 234#define _ALL_SOURCE 1
 235#endif
 236
 237/* used on Mac OS X */
 238#ifdef PRECOMPOSE_UNICODE
 239#include "compat/precompose_utf8.h"
 240#else
 241#define precompose_str(in,i_nfd2nfc)
 242#define precompose_argv(c,v)
 243#define probe_utf8_pathname_composition()
 244#endif
 245
 246#ifdef MKDIR_WO_TRAILING_SLASH
 247#define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 248extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
 249#endif
 250
 251#ifdef NO_STRUCT_ITIMERVAL
 252struct itimerval {
 253        struct timeval it_interval;
 254        struct timeval it_value;
 255};
 256#endif
 257
 258#ifdef NO_SETITIMER
 259#define setitimer(which,value,ovalue)
 260#endif
 261
 262#ifndef NO_LIBGEN_H
 263#include <libgen.h>
 264#else
 265#define basename gitbasename
 266extern char *gitbasename(char *);
 267#define dirname gitdirname
 268extern char *gitdirname(char *);
 269#endif
 270
 271#ifndef NO_ICONV
 272#include <iconv.h>
 273#endif
 274
 275#ifndef NO_OPENSSL
 276#ifdef __APPLE__
 277#define __AVAILABILITY_MACROS_USES_AVAILABILITY 0
 278#include <AvailabilityMacros.h>
 279#undef DEPRECATED_ATTRIBUTE
 280#define DEPRECATED_ATTRIBUTE
 281#undef __AVAILABILITY_MACROS_USES_AVAILABILITY
 282#endif
 283#include <openssl/ssl.h>
 284#include <openssl/err.h>
 285#endif
 286
 287/* On most systems <netdb.h> would have given us this, but
 288 * not on some systems (e.g. z/OS).
 289 */
 290#ifndef NI_MAXHOST
 291#define NI_MAXHOST 1025
 292#endif
 293
 294#ifndef NI_MAXSERV
 295#define NI_MAXSERV 32
 296#endif
 297
 298/* On most systems <limits.h> would have given us this, but
 299 * not on some systems (e.g. GNU/Hurd).
 300 */
 301#ifndef PATH_MAX
 302#define PATH_MAX 4096
 303#endif
 304
 305#ifndef PRIuMAX
 306#define PRIuMAX "llu"
 307#endif
 308
 309#ifndef SCNuMAX
 310#define SCNuMAX PRIuMAX
 311#endif
 312
 313#ifndef PRIu32
 314#define PRIu32 "u"
 315#endif
 316
 317#ifndef PRIx32
 318#define PRIx32 "x"
 319#endif
 320
 321#ifndef PRIo32
 322#define PRIo32 "o"
 323#endif
 324
 325typedef uintmax_t timestamp_t;
 326#define PRItime PRIuMAX
 327#define parse_timestamp strtoumax
 328#define TIME_MAX UINTMAX_MAX
 329
 330#ifndef PATH_SEP
 331#define PATH_SEP ':'
 332#endif
 333
 334#ifdef HAVE_PATHS_H
 335#include <paths.h>
 336#endif
 337#ifndef _PATH_DEFPATH
 338#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
 339#endif
 340
 341#ifndef has_dos_drive_prefix
 342static inline int git_has_dos_drive_prefix(const char *path)
 343{
 344        return 0;
 345}
 346#define has_dos_drive_prefix git_has_dos_drive_prefix
 347#endif
 348
 349#ifndef skip_dos_drive_prefix
 350static inline int git_skip_dos_drive_prefix(char **path)
 351{
 352        return 0;
 353}
 354#define skip_dos_drive_prefix git_skip_dos_drive_prefix
 355#endif
 356
 357#ifndef is_dir_sep
 358static inline int git_is_dir_sep(int c)
 359{
 360        return c == '/';
 361}
 362#define is_dir_sep git_is_dir_sep
 363#endif
 364
 365#ifndef offset_1st_component
 366static inline int git_offset_1st_component(const char *path)
 367{
 368        return is_dir_sep(path[0]);
 369}
 370#define offset_1st_component git_offset_1st_component
 371#endif
 372
 373#ifndef find_last_dir_sep
 374static inline char *git_find_last_dir_sep(const char *path)
 375{
 376        return strrchr(path, '/');
 377}
 378#define find_last_dir_sep git_find_last_dir_sep
 379#endif
 380
 381#if defined(__HP_cc) && (__HP_cc >= 61000)
 382#define NORETURN __attribute__((noreturn))
 383#define NORETURN_PTR
 384#elif defined(__GNUC__) && !defined(NO_NORETURN)
 385#define NORETURN __attribute__((__noreturn__))
 386#define NORETURN_PTR __attribute__((__noreturn__))
 387#elif defined(_MSC_VER)
 388#define NORETURN __declspec(noreturn)
 389#define NORETURN_PTR
 390#else
 391#define NORETURN
 392#define NORETURN_PTR
 393#ifndef __GNUC__
 394#ifndef __attribute__
 395#define __attribute__(x)
 396#endif
 397#endif
 398#endif
 399
 400/* The sentinel attribute is valid from gcc version 4.0 */
 401#if defined(__GNUC__) && (__GNUC__ >= 4)
 402#define LAST_ARG_MUST_BE_NULL __attribute__((sentinel))
 403#else
 404#define LAST_ARG_MUST_BE_NULL
 405#endif
 406
 407#include "compat/bswap.h"
 408
 409#include "wildmatch.h"
 410
 411struct strbuf;
 412
 413/* General helper functions */
 414extern void vreportf(const char *prefix, const char *err, va_list params);
 415extern NORETURN void usage(const char *err);
 416extern NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 417extern NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 418extern NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 419extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 420extern int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 421extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
 422extern void warning_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 423
 424#ifndef NO_OPENSSL
 425#ifdef APPLE_COMMON_CRYPTO
 426#include "compat/apple-common-crypto.h"
 427#else
 428#include <openssl/evp.h>
 429#include <openssl/hmac.h>
 430#endif /* APPLE_COMMON_CRYPTO */
 431#include <openssl/x509v3.h>
 432#endif /* NO_OPENSSL */
 433
 434/*
 435 * Let callers be aware of the constant return value; this can help
 436 * gcc with -Wuninitialized analysis. We restrict this trick to gcc, though,
 437 * because some compilers may not support variadic macros. Since we're only
 438 * trying to help gcc, anyway, it's OK; other compilers will fall back to
 439 * using the function as usual.
 440 */
 441#if defined(__GNUC__)
 442static inline int const_error(void)
 443{
 444        return -1;
 445}
 446#define error(...) (error(__VA_ARGS__), const_error())
 447#define error_errno(...) (error_errno(__VA_ARGS__), const_error())
 448#endif
 449
 450extern void set_die_routine(NORETURN_PTR void (*routine)(const char *err, va_list params));
 451extern void set_error_routine(void (*routine)(const char *err, va_list params));
 452extern void (*get_error_routine(void))(const char *err, va_list params);
 453extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
 454extern void (*get_warn_routine(void))(const char *warn, va_list params);
 455extern void set_die_is_recursing_routine(int (*routine)(void));
 456
 457extern int starts_with(const char *str, const char *prefix);
 458
 459/*
 460 * If the string "str" begins with the string found in "prefix", return 1.
 461 * The "out" parameter is set to "str + strlen(prefix)" (i.e., to the point in
 462 * the string right after the prefix).
 463 *
 464 * Otherwise, return 0 and leave "out" untouched.
 465 *
 466 * Examples:
 467 *
 468 *   [extract branch name, fail if not a branch]
 469 *   if (!skip_prefix(ref, "refs/heads/", &branch)
 470 *      return -1;
 471 *
 472 *   [skip prefix if present, otherwise use whole string]
 473 *   skip_prefix(name, "refs/heads/", &name);
 474 */
 475static inline int skip_prefix(const char *str, const char *prefix,
 476                              const char **out)
 477{
 478        do {
 479                if (!*prefix) {
 480                        *out = str;
 481                        return 1;
 482                }
 483        } while (*str++ == *prefix++);
 484        return 0;
 485}
 486
 487/*
 488 * Like skip_prefix, but promises never to read past "len" bytes of the input
 489 * buffer, and returns the remaining number of bytes in "out" via "outlen".
 490 */
 491static inline int skip_prefix_mem(const char *buf, size_t len,
 492                                  const char *prefix,
 493                                  const char **out, size_t *outlen)
 494{
 495        size_t prefix_len = strlen(prefix);
 496        if (prefix_len <= len && !memcmp(buf, prefix, prefix_len)) {
 497                *out = buf + prefix_len;
 498                *outlen = len - prefix_len;
 499                return 1;
 500        }
 501        return 0;
 502}
 503
 504/*
 505 * If buf ends with suffix, return 1 and subtract the length of the suffix
 506 * from *len. Otherwise, return 0 and leave *len untouched.
 507 */
 508static inline int strip_suffix_mem(const char *buf, size_t *len,
 509                                   const char *suffix)
 510{
 511        size_t suflen = strlen(suffix);
 512        if (*len < suflen || memcmp(buf + (*len - suflen), suffix, suflen))
 513                return 0;
 514        *len -= suflen;
 515        return 1;
 516}
 517
 518/*
 519 * If str ends with suffix, return 1 and set *len to the size of the string
 520 * without the suffix. Otherwise, return 0 and set *len to the size of the
 521 * string.
 522 *
 523 * Note that we do _not_ NUL-terminate str to the new length.
 524 */
 525static inline int strip_suffix(const char *str, const char *suffix, size_t *len)
 526{
 527        *len = strlen(str);
 528        return strip_suffix_mem(str, len, suffix);
 529}
 530
 531static inline int ends_with(const char *str, const char *suffix)
 532{
 533        size_t len;
 534        return strip_suffix(str, suffix, &len);
 535}
 536
 537#define SWAP(a, b) do {                                         \
 538        void *_swap_a_ptr = &(a);                               \
 539        void *_swap_b_ptr = &(b);                               \
 540        unsigned char _swap_buffer[sizeof(a)];                  \
 541        memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));           \
 542        memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +            \
 543               BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));   \
 544        memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));           \
 545} while (0)
 546
 547#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 548
 549#ifndef PROT_READ
 550#define PROT_READ 1
 551#define PROT_WRITE 2
 552#define MAP_PRIVATE 1
 553#endif
 554
 555#define mmap git_mmap
 556#define munmap git_munmap
 557extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 558extern int git_munmap(void *start, size_t length);
 559
 560#else /* NO_MMAP || USE_WIN32_MMAP */
 561
 562#include <sys/mman.h>
 563
 564#endif /* NO_MMAP || USE_WIN32_MMAP */
 565
 566#ifdef NO_MMAP
 567
 568/* This value must be multiple of (pagesize * 2) */
 569#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
 570
 571#else /* NO_MMAP */
 572
 573/* This value must be multiple of (pagesize * 2) */
 574#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
 575        (sizeof(void*) >= 8 \
 576                ?  1 * 1024 * 1024 * 1024 \
 577                : 32 * 1024 * 1024)
 578
 579#endif /* NO_MMAP */
 580
 581#ifndef MAP_FAILED
 582#define MAP_FAILED ((void *)-1)
 583#endif
 584
 585#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
 586#define on_disk_bytes(st) ((st).st_size)
 587#else
 588#define on_disk_bytes(st) ((st).st_blocks * 512)
 589#endif
 590
 591#ifdef NEEDS_MODE_TRANSLATION
 592#undef S_IFMT
 593#undef S_IFREG
 594#undef S_IFDIR
 595#undef S_IFLNK
 596#undef S_IFBLK
 597#undef S_IFCHR
 598#undef S_IFIFO
 599#undef S_IFSOCK
 600#define S_IFMT   0170000
 601#define S_IFREG  0100000
 602#define S_IFDIR  0040000
 603#define S_IFLNK  0120000
 604#define S_IFBLK  0060000
 605#define S_IFCHR  0020000
 606#define S_IFIFO  0010000
 607#define S_IFSOCK 0140000
 608#ifdef stat
 609#undef stat
 610#endif
 611#define stat(path, buf) git_stat(path, buf)
 612extern int git_stat(const char *, struct stat *);
 613#ifdef fstat
 614#undef fstat
 615#endif
 616#define fstat(fd, buf) git_fstat(fd, buf)
 617extern int git_fstat(int, struct stat *);
 618#ifdef lstat
 619#undef lstat
 620#endif
 621#define lstat(path, buf) git_lstat(path, buf)
 622extern int git_lstat(const char *, struct stat *);
 623#endif
 624
 625#define DEFAULT_PACKED_GIT_LIMIT \
 626        ((1024L * 1024L) * (size_t)(sizeof(void*) >= 8 ? (32 * 1024L * 1024L) : 256))
 627
 628#ifdef NO_PREAD
 629#define pread git_pread
 630extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 631#endif
 632/*
 633 * Forward decl that will remind us if its twin in cache.h changes.
 634 * This function is used in compat/pread.c.  But we can't include
 635 * cache.h there.
 636 */
 637extern ssize_t read_in_full(int fd, void *buf, size_t count);
 638
 639#ifdef NO_SETENV
 640#define setenv gitsetenv
 641extern int gitsetenv(const char *, const char *, int);
 642#endif
 643
 644#ifdef NO_MKDTEMP
 645#define mkdtemp gitmkdtemp
 646extern char *gitmkdtemp(char *);
 647#endif
 648
 649#ifdef NO_UNSETENV
 650#define unsetenv gitunsetenv
 651extern void gitunsetenv(const char *);
 652#endif
 653
 654#ifdef NO_STRCASESTR
 655#define strcasestr gitstrcasestr
 656extern char *gitstrcasestr(const char *haystack, const char *needle);
 657#endif
 658
 659#ifdef NO_STRLCPY
 660#define strlcpy gitstrlcpy
 661extern size_t gitstrlcpy(char *, const char *, size_t);
 662#endif
 663
 664#ifdef NO_STRTOUMAX
 665#define strtoumax gitstrtoumax
 666extern uintmax_t gitstrtoumax(const char *, char **, int);
 667#define strtoimax gitstrtoimax
 668extern intmax_t gitstrtoimax(const char *, char **, int);
 669#endif
 670
 671#ifdef NO_HSTRERROR
 672#define hstrerror githstrerror
 673extern const char *githstrerror(int herror);
 674#endif
 675
 676#ifdef NO_MEMMEM
 677#define memmem gitmemmem
 678void *gitmemmem(const void *haystack, size_t haystacklen,
 679                const void *needle, size_t needlelen);
 680#endif
 681
 682#ifdef OVERRIDE_STRDUP
 683#ifdef strdup
 684#undef strdup
 685#endif
 686#define strdup gitstrdup
 687char *gitstrdup(const char *s);
 688#endif
 689
 690#ifdef NO_GETPAGESIZE
 691#define getpagesize() sysconf(_SC_PAGESIZE)
 692#endif
 693
 694#ifndef O_CLOEXEC
 695#define O_CLOEXEC 0
 696#endif
 697
 698#ifdef FREAD_READS_DIRECTORIES
 699# if !defined(SUPPRESS_FOPEN_REDEFINITION)
 700#  ifdef fopen
 701#   undef fopen
 702#  endif
 703#  define fopen(a,b) git_fopen(a,b)
 704# endif
 705extern FILE *git_fopen(const char*, const char*);
 706#endif
 707
 708#ifdef SNPRINTF_RETURNS_BOGUS
 709#ifdef snprintf
 710#undef snprintf
 711#endif
 712#define snprintf git_snprintf
 713extern int git_snprintf(char *str, size_t maxsize,
 714                        const char *format, ...);
 715#ifdef vsnprintf
 716#undef vsnprintf
 717#endif
 718#define vsnprintf git_vsnprintf
 719extern int git_vsnprintf(char *str, size_t maxsize,
 720                         const char *format, va_list ap);
 721#endif
 722
 723#ifdef __GLIBC_PREREQ
 724#if __GLIBC_PREREQ(2, 1)
 725#define HAVE_STRCHRNUL
 726#endif
 727#endif
 728
 729#ifndef HAVE_STRCHRNUL
 730#define strchrnul gitstrchrnul
 731static inline char *gitstrchrnul(const char *s, int c)
 732{
 733        while (*s && *s != c)
 734                s++;
 735        return (char *)s;
 736}
 737#endif
 738
 739#ifdef NO_INET_PTON
 740int inet_pton(int af, const char *src, void *dst);
 741#endif
 742
 743#ifdef NO_INET_NTOP
 744const char *inet_ntop(int af, const void *src, char *dst, size_t size);
 745#endif
 746
 747#ifdef NO_PTHREADS
 748#define atexit git_atexit
 749extern int git_atexit(void (*handler)(void));
 750#endif
 751
 752extern void release_pack_memory(size_t);
 753
 754typedef void (*try_to_free_t)(size_t);
 755extern try_to_free_t set_try_to_free_routine(try_to_free_t);
 756
 757static inline size_t st_add(size_t a, size_t b)
 758{
 759        if (unsigned_add_overflows(a, b))
 760                die("size_t overflow: %"PRIuMAX" + %"PRIuMAX,
 761                    (uintmax_t)a, (uintmax_t)b);
 762        return a + b;
 763}
 764#define st_add3(a,b,c)   st_add(st_add((a),(b)),(c))
 765#define st_add4(a,b,c,d) st_add(st_add3((a),(b),(c)),(d))
 766
 767static inline size_t st_mult(size_t a, size_t b)
 768{
 769        if (unsigned_mult_overflows(a, b))
 770                die("size_t overflow: %"PRIuMAX" * %"PRIuMAX,
 771                    (uintmax_t)a, (uintmax_t)b);
 772        return a * b;
 773}
 774
 775static inline size_t st_sub(size_t a, size_t b)
 776{
 777        if (a < b)
 778                die("size_t underflow: %"PRIuMAX" - %"PRIuMAX,
 779                    (uintmax_t)a, (uintmax_t)b);
 780        return a - b;
 781}
 782
 783#ifdef HAVE_ALLOCA_H
 784# include <alloca.h>
 785# define xalloca(size)      (alloca(size))
 786# define xalloca_free(p)    do {} while (0)
 787#else
 788# define xalloca(size)      (xmalloc(size))
 789# define xalloca_free(p)    (free(p))
 790#endif
 791extern char *xstrdup(const char *str);
 792extern void *xmalloc(size_t size);
 793extern void *xmallocz(size_t size);
 794extern void *xmallocz_gently(size_t size);
 795extern void *xmemdupz(const void *data, size_t len);
 796extern char *xstrndup(const char *str, size_t len);
 797extern void *xrealloc(void *ptr, size_t size);
 798extern void *xcalloc(size_t nmemb, size_t size);
 799extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 800extern void *xmmap_gently(void *start, size_t length, int prot, int flags, int fd, off_t offset);
 801extern int xopen(const char *path, int flags, ...);
 802extern ssize_t xread(int fd, void *buf, size_t len);
 803extern ssize_t xwrite(int fd, const void *buf, size_t len);
 804extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
 805extern int xdup(int fd);
 806extern FILE *xfopen(const char *path, const char *mode);
 807extern FILE *xfdopen(int fd, const char *mode);
 808extern int xmkstemp(char *template);
 809extern int xmkstemp_mode(char *template, int mode);
 810extern char *xgetcwd(void);
 811extern FILE *fopen_for_writing(const char *path);
 812extern FILE *fopen_or_warn(const char *path, const char *mode);
 813
 814/*
 815 * FREE_AND_NULL(ptr) is like free(ptr) followed by ptr = NULL. Note
 816 * that ptr is used twice, so don't pass e.g. ptr++.
 817 */
 818#define FREE_AND_NULL(p) do { free(p); (p) = NULL; } while (0)
 819
 820#define ALLOC_ARRAY(x, alloc) (x) = xmalloc(st_mult(sizeof(*(x)), (alloc)))
 821#define REALLOC_ARRAY(x, alloc) (x) = xrealloc((x), st_mult(sizeof(*(x)), (alloc)))
 822
 823#define COPY_ARRAY(dst, src, n) copy_array((dst), (src), (n), sizeof(*(dst)) + \
 824        BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 825static inline void copy_array(void *dst, const void *src, size_t n, size_t size)
 826{
 827        if (n)
 828                memcpy(dst, src, st_mult(size, n));
 829}
 830
 831#define MOVE_ARRAY(dst, src, n) move_array((dst), (src), (n), sizeof(*(dst)) + \
 832        BUILD_ASSERT_OR_ZERO(sizeof(*(dst)) == sizeof(*(src))))
 833static inline void move_array(void *dst, const void *src, size_t n, size_t size)
 834{
 835        if (n)
 836                memmove(dst, src, st_mult(size, n));
 837}
 838
 839/*
 840 * These functions help you allocate structs with flex arrays, and copy
 841 * the data directly into the array. For example, if you had:
 842 *
 843 *   struct foo {
 844 *     int bar;
 845 *     char name[FLEX_ARRAY];
 846 *   };
 847 *
 848 * you can do:
 849 *
 850 *   struct foo *f;
 851 *   FLEX_ALLOC_MEM(f, name, src, len);
 852 *
 853 * to allocate a "foo" with the contents of "src" in the "name" field.
 854 * The resulting struct is automatically zero'd, and the flex-array field
 855 * is NUL-terminated (whether the incoming src buffer was or not).
 856 *
 857 * The FLEXPTR_* variants operate on structs that don't use flex-arrays,
 858 * but do want to store a pointer to some extra data in the same allocated
 859 * block. For example, if you have:
 860 *
 861 *   struct foo {
 862 *     char *name;
 863 *     int bar;
 864 *   };
 865 *
 866 * you can do:
 867 *
 868 *   struct foo *f;
 869 *   FLEXPTR_ALLOC_STR(f, name, src);
 870 *
 871 * and "name" will point to a block of memory after the struct, which will be
 872 * freed along with the struct (but the pointer can be repointed anywhere).
 873 *
 874 * The *_STR variants accept a string parameter rather than a ptr/len
 875 * combination.
 876 *
 877 * Note that these macros will evaluate the first parameter multiple
 878 * times, and it must be assignable as an lvalue.
 879 */
 880#define FLEX_ALLOC_MEM(x, flexname, buf, len) do { \
 881        size_t flex_array_len_ = (len); \
 882        (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 883        memcpy((void *)(x)->flexname, (buf), flex_array_len_); \
 884} while (0)
 885#define FLEXPTR_ALLOC_MEM(x, ptrname, buf, len) do { \
 886        size_t flex_array_len_ = (len); \
 887        (x) = xcalloc(1, st_add3(sizeof(*(x)), flex_array_len_, 1)); \
 888        memcpy((x) + 1, (buf), flex_array_len_); \
 889        (x)->ptrname = (void *)((x)+1); \
 890} while(0)
 891#define FLEX_ALLOC_STR(x, flexname, str) \
 892        FLEX_ALLOC_MEM((x), flexname, (str), strlen(str))
 893#define FLEXPTR_ALLOC_STR(x, ptrname, str) \
 894        FLEXPTR_ALLOC_MEM((x), ptrname, (str), strlen(str))
 895
 896static inline char *xstrdup_or_null(const char *str)
 897{
 898        return str ? xstrdup(str) : NULL;
 899}
 900
 901static inline size_t xsize_t(off_t len)
 902{
 903        if (len > (size_t) len)
 904                die("Cannot handle files this big");
 905        return (size_t)len;
 906}
 907
 908__attribute__((format (printf, 3, 4)))
 909extern int xsnprintf(char *dst, size_t max, const char *fmt, ...);
 910
 911#ifndef HOST_NAME_MAX
 912#define HOST_NAME_MAX 256
 913#endif
 914
 915extern int xgethostname(char *buf, size_t len);
 916
 917/* in ctype.c, for kwset users */
 918extern const unsigned char tolower_trans_tbl[256];
 919
 920/* Sane ctype - no locale, and works with signed chars */
 921#undef isascii
 922#undef isspace
 923#undef isdigit
 924#undef isalpha
 925#undef isalnum
 926#undef isprint
 927#undef islower
 928#undef isupper
 929#undef tolower
 930#undef toupper
 931#undef iscntrl
 932#undef ispunct
 933#undef isxdigit
 934
 935extern const unsigned char sane_ctype[256];
 936#define GIT_SPACE 0x01
 937#define GIT_DIGIT 0x02
 938#define GIT_ALPHA 0x04
 939#define GIT_GLOB_SPECIAL 0x08
 940#define GIT_REGEX_SPECIAL 0x10
 941#define GIT_PATHSPEC_MAGIC 0x20
 942#define GIT_CNTRL 0x40
 943#define GIT_PUNCT 0x80
 944#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
 945#define isascii(x) (((x) & ~0x7f) == 0)
 946#define isspace(x) sane_istest(x,GIT_SPACE)
 947#define isdigit(x) sane_istest(x,GIT_DIGIT)
 948#define isalpha(x) sane_istest(x,GIT_ALPHA)
 949#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
 950#define isprint(x) ((x) >= 0x20 && (x) <= 0x7e)
 951#define islower(x) sane_iscase(x, 1)
 952#define isupper(x) sane_iscase(x, 0)
 953#define is_glob_special(x) sane_istest(x,GIT_GLOB_SPECIAL)
 954#define is_regex_special(x) sane_istest(x,GIT_GLOB_SPECIAL | GIT_REGEX_SPECIAL)
 955#define iscntrl(x) (sane_istest(x,GIT_CNTRL))
 956#define ispunct(x) sane_istest(x, GIT_PUNCT | GIT_REGEX_SPECIAL | \
 957                GIT_GLOB_SPECIAL | GIT_PATHSPEC_MAGIC)
 958#define isxdigit(x) (hexval_table[(unsigned char)(x)] != -1)
 959#define tolower(x) sane_case((unsigned char)(x), 0x20)
 960#define toupper(x) sane_case((unsigned char)(x), 0)
 961#define is_pathspec_magic(x) sane_istest(x,GIT_PATHSPEC_MAGIC)
 962
 963static inline int sane_case(int x, int high)
 964{
 965        if (sane_istest(x, GIT_ALPHA))
 966                x = (x & ~0x20) | high;
 967        return x;
 968}
 969
 970static inline int sane_iscase(int x, int is_lower)
 971{
 972        if (!sane_istest(x, GIT_ALPHA))
 973                return 0;
 974
 975        if (is_lower)
 976                return (x & 0x20) != 0;
 977        else
 978                return (x & 0x20) == 0;
 979}
 980
 981static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 982{
 983        unsigned long ul;
 984        char *p;
 985
 986        errno = 0;
 987        /* negative values would be accepted by strtoul */
 988        if (strchr(s, '-'))
 989                return -1;
 990        ul = strtoul(s, &p, base);
 991        if (errno || *p || p == s || (unsigned int) ul != ul)
 992                return -1;
 993        *result = ul;
 994        return 0;
 995}
 996
 997static inline int strtol_i(char const *s, int base, int *result)
 998{
 999        long ul;
1000        char *p;
1001
1002        errno = 0;
1003        ul = strtol(s, &p, base);
1004        if (errno || *p || p == s || (int) ul != ul)
1005                return -1;
1006        *result = ul;
1007        return 0;
1008}
1009
1010#ifdef INTERNAL_QSORT
1011void git_qsort(void *base, size_t nmemb, size_t size,
1012               int(*compar)(const void *, const void *));
1013#define qsort git_qsort
1014#endif
1015
1016#define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
1017static inline void sane_qsort(void *base, size_t nmemb, size_t size,
1018                              int(*compar)(const void *, const void *))
1019{
1020        if (nmemb > 1)
1021                qsort(base, nmemb, size, compar);
1022}
1023
1024#ifndef HAVE_ISO_QSORT_S
1025int git_qsort_s(void *base, size_t nmemb, size_t size,
1026                int (*compar)(const void *, const void *, void *), void *ctx);
1027#define qsort_s git_qsort_s
1028#endif
1029
1030#define QSORT_S(base, n, compar, ctx) do {                      \
1031        if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
1032                die("BUG: qsort_s() failed");                   \
1033} while (0)
1034
1035#ifndef REG_STARTEND
1036#error "Git requires REG_STARTEND support. Compile with NO_REGEX=NeedsStartEnd"
1037#endif
1038
1039static inline int regexec_buf(const regex_t *preg, const char *buf, size_t size,
1040                              size_t nmatch, regmatch_t pmatch[], int eflags)
1041{
1042        assert(nmatch > 0 && pmatch);
1043        pmatch[0].rm_so = 0;
1044        pmatch[0].rm_eo = size;
1045        return regexec(preg, buf, nmatch, pmatch, eflags | REG_STARTEND);
1046}
1047
1048#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
1049# define FORCE_DIR_SET_GID S_ISGID
1050#else
1051# define FORCE_DIR_SET_GID 0
1052#endif
1053
1054#ifdef NO_NSEC
1055#undef USE_NSEC
1056#define ST_CTIME_NSEC(st) 0
1057#define ST_MTIME_NSEC(st) 0
1058#else
1059#ifdef USE_ST_TIMESPEC
1060#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
1061#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
1062#else
1063#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
1064#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
1065#endif
1066#endif
1067
1068#ifdef UNRELIABLE_FSTAT
1069#define fstat_is_reliable() 0
1070#else
1071#define fstat_is_reliable() 1
1072#endif
1073
1074#ifndef va_copy
1075/*
1076 * Since an obvious implementation of va_list would be to make it a
1077 * pointer into the stack frame, a simple assignment will work on
1078 * many systems.  But let's try to be more portable.
1079 */
1080#ifdef __va_copy
1081#define va_copy(dst, src) __va_copy(dst, src)
1082#else
1083#define va_copy(dst, src) ((dst) = (src))
1084#endif
1085#endif
1086
1087#if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__C99_MACRO_WITH_VA_ARGS)
1088#define HAVE_VARIADIC_MACROS 1
1089#endif
1090
1091#ifdef HAVE_VARIADIC_MACROS
1092__attribute__((format (printf, 3, 4))) NORETURN
1093void BUG_fl(const char *file, int line, const char *fmt, ...);
1094#define BUG(...) BUG_fl(__FILE__, __LINE__, __VA_ARGS__)
1095#else
1096__attribute__((format (printf, 1, 2))) NORETURN
1097void BUG(const char *fmt, ...);
1098#endif
1099
1100/*
1101 * Preserves errno, prints a message, but gives no warning for ENOENT.
1102 * Returns 0 on success, which includes trying to unlink an object that does
1103 * not exist.
1104 */
1105int unlink_or_warn(const char *path);
1106 /*
1107  * Tries to unlink file.  Returns 0 if unlink succeeded
1108  * or the file already didn't exist.  Returns -1 and
1109  * appends a message to err suitable for
1110  * 'error("%s", err->buf)' on error.
1111  */
1112int unlink_or_msg(const char *file, struct strbuf *err);
1113/*
1114 * Preserves errno, prints a message, but gives no warning for ENOENT.
1115 * Returns 0 on success, which includes trying to remove a directory that does
1116 * not exist.
1117 */
1118int rmdir_or_warn(const char *path);
1119/*
1120 * Calls the correct function out of {unlink,rmdir}_or_warn based on
1121 * the supplied file mode.
1122 */
1123int remove_or_warn(unsigned int mode, const char *path);
1124
1125/*
1126 * Call access(2), but warn for any error except "missing file"
1127 * (ENOENT or ENOTDIR).
1128 */
1129#define ACCESS_EACCES_OK (1U << 0)
1130int access_or_warn(const char *path, int mode, unsigned flag);
1131int access_or_die(const char *path, int mode, unsigned flag);
1132
1133/* Warn on an inaccessible file if errno indicates this is an error */
1134int warn_on_fopen_errors(const char *path);
1135
1136#ifdef GMTIME_UNRELIABLE_ERRORS
1137struct tm *git_gmtime(const time_t *);
1138struct tm *git_gmtime_r(const time_t *, struct tm *);
1139#define gmtime git_gmtime
1140#define gmtime_r git_gmtime_r
1141#endif
1142
1143#if !defined(USE_PARENS_AROUND_GETTEXT_N) && defined(__GNUC__)
1144#define USE_PARENS_AROUND_GETTEXT_N 1
1145#endif
1146
1147#ifndef SHELL_PATH
1148# define SHELL_PATH "/bin/sh"
1149#endif
1150
1151#ifndef _POSIX_THREAD_SAFE_FUNCTIONS
1152#define flockfile(fh)
1153#define funlockfile(fh)
1154#define getc_unlocked(fh) getc(fh)
1155#endif
1156
1157/*
1158 * Our code often opens a path to an optional file, to work on its
1159 * contents when we can successfully open it.  We can ignore a failure
1160 * to open if such an optional file does not exist, but we do want to
1161 * report a failure in opening for other reasons (e.g. we got an I/O
1162 * error, or the file is there, but we lack the permission to open).
1163 *
1164 * Call this function after seeing an error from open() or fopen() to
1165 * see if the errno indicates a missing file that we can safely ignore.
1166 */
1167static inline int is_missing_file_error(int errno_)
1168{
1169        return (errno_ == ENOENT || errno_ == ENOTDIR);
1170}
1171
1172extern int cmd_main(int, const char **);
1173
1174#endif