lib/replace/replace.h

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    macros to go along with the lib/replace/ portability layer code
   5
   6    Copyright (C) Andrew Tridgell 2005
   7    Copyright (C) Jelmer Vernooij 2006-2008
   8    Copyright (C) Jeremy Allison 2007.
   9
  10      ** NOTE! The following LGPL license applies to the replace
  11      ** library. This does NOT imply that all of Samba is released
  12      ** under the LGPL
  13
  14    This library is free software; you can redistribute it and/or
  15    modify it under the terms of the GNU Lesser General Public
  16    License as published by the Free Software Foundation; either
  17    version 3 of the License, or (at your option) any later version.
  18
  19    This library is distributed in the hope that it will be useful,
  20    but WITHOUT ANY WARRANTY; without even the implied warranty of
  21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22    Lesser General Public License for more details.
  23
  24    You should have received a copy of the GNU Lesser General Public
  25    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  26 */
  27
  28 #ifndef _LIBREPLACE_REPLACE_H
  29 #define _LIBREPLACE_REPLACE_H
  30
  31 #ifndef NO_CONFIG_H
  32 #include "config.h"
  33 #endif
  34
  35 #ifdef HAVE_STANDARDS_H
  36 #include <standards.h>
  37 #endif
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <stdarg.h>
  42 #include <errno.h>
  43
  44 #if defined(_MSC_VER) || defined(__MINGW32__)
  45 #include "win32_replace.h"
  46 #endif
  47
  48
  49 #ifdef HAVE_STDINT_H
  50 #include <stdint.h>
  51 /* force off HAVE_INTTYPES_H so that roken doesn't try to include both,
  52    which causes a warning storm on irix */
  53 #undef HAVE_INTTYPES_H
  54 #elif HAVE_INTTYPES_H
  55 #define __STDC_FORMAT_MACROS
  56 #include <inttypes.h>
  57 #endif
  58
  59 #ifndef __PRI64_PREFIX
  60 # if __WORDSIZE == 64
  61 #  define __PRI64_PREFIX        "l"
  62 # else
  63 #  define __PRI64_PREFIX        "ll"
  64 # endif
  65 #endif
  66
  67 /* Decimal notation.  */
  68 #ifndef PRId8
  69 # define PRId8          "d"
  70 #endif
  71 #ifndef PRId16
  72 # define PRId16         "d"
  73 #endif
  74 #ifndef PRId32
  75 # define PRId32         "d"
  76 #endif
  77 #ifndef PRId64
  78 # define PRId64         __PRI64_PREFIX "d"
  79 #endif
  80
  81 #ifndef PRIi8
  82 # define PRIi8          "i"
  83 #endif
  84 #ifndef PRIi16
  85 # define PRIi16         "i"
  86 #endif
  87 #ifndef PRIi32
  88 # define PRIi32         "i"
  89 #endif
  90 #ifndef PRIi64
  91 # define PRIi64         __PRI64_PREFIX "i"
  92 #endif
  93
  94 #ifndef PRIu8
  95 # define PRIu8          "u"
  96 #endif
  97 #ifndef PRIu16
  98 # define PRIu16         "u"
  99 #endif
 100 #ifndef PRIu32
 101 # define PRIu32         "u"
 102 #endif
 103 #ifndef PRIu64
 104 # define PRIu64         __PRI64_PREFIX "u"
 105 #endif
 106
 107 #ifdef HAVE_STRING_H
 108 #include <string.h>
 109 #endif
 110
 111 #ifdef HAVE_STRINGS_H
 112 #include <strings.h>
 113 #endif
 114
 115 #ifdef HAVE_SYS_TYPES_H
 116 #include <sys/types.h>
 117 #endif
 118
 119 #if STDC_HEADERS
 120 #include <stdlib.h>
 121 #include <stddef.h>
 122 #endif
 123
 124 #ifndef HAVE_STRERROR
 125 extern char *sys_errlist[];
 126 #define strerror(i) sys_errlist[i]
 127 #endif
 128
 129 #ifndef HAVE_ERRNO_DECL
 130 extern int errno;
 131 #endif
 132
 133 #ifndef HAVE_STRDUP
 134 #define strdup rep_strdup
 135 char *rep_strdup(const char *s);
 136 #endif
 137
 138 #ifndef HAVE_MEMMOVE
 139 #define memmove rep_memmove
 140 void *rep_memmove(void *dest,const void *src,int size);
 141 #endif
 142
 143 #ifndef HAVE_MEMMEM
 144 #define memmem rep_memmem
 145 void *rep_memmem(const void *haystack, size_t haystacklen,
 146                  const void *needle, size_t needlelen);
 147 #endif
 148
 149 #ifndef HAVE_MKTIME
 150 #define mktime rep_mktime
 151 /* prototype is in "system/time.h" */
 152 #endif
 153
 154 #ifndef HAVE_TIMEGM
 155 #define timegm rep_timegm
 156 /* prototype is in "system/time.h" */
 157 #endif
 158
 159 #ifndef HAVE_UTIME
 160 #define utime rep_utime
 161 /* prototype is in "system/time.h" */
 162 #endif
 163
 164 #ifndef HAVE_UTIMES
 165 #define utimes rep_utimes
 166 /* prototype is in "system/time.h" */
 167 #endif
 168
 169 #ifndef HAVE_STRLCPY
 170 #define strlcpy rep_strlcpy
 171 size_t rep_strlcpy(char *d, const char *s, size_t bufsize);
 172 #endif
 173
 174 #ifndef HAVE_STRLCAT
 175 #define strlcat rep_strlcat
 176 size_t rep_strlcat(char *d, const char *s, size_t bufsize);
 177 #endif
 178
 179 #if (defined(BROKEN_STRNDUP) || !defined(HAVE_STRNDUP))
 180 #undef HAVE_STRNDUP
 181 #define strndup rep_strndup
 182 char *rep_strndup(const char *s, size_t n);
 183 #endif
 184
 185 #if (defined(BROKEN_STRNLEN) || !defined(HAVE_STRNLEN))
 186 #undef HAVE_STRNLEN
 187 #define strnlen rep_strnlen
 188 size_t rep_strnlen(const char *s, size_t n);
 189 #endif
 190
 191 #if !HAVE_DECL_ENVIRON
 192 #ifdef __APPLE__
 193 #include <crt_externs.h>
 194 #define environ (*_NSGetEnviron())
 195 #else
 196 extern char **environ;
 197 #endif
 198 #endif
 199
 200 #ifndef HAVE_SETENV
 201 #define setenv rep_setenv
 202 int rep_setenv(const char *name, const char *value, int overwrite);
 203 #else
 204 #ifndef HAVE_SETENV_DECL
 205 int setenv(const char *name, const char *value, int overwrite);
 206 #endif
 207 #endif
 208
 209 #ifndef HAVE_UNSETENV
 210 #define unsetenv rep_unsetenv
 211 int rep_unsetenv(const char *name);
 212 #endif
 213
 214 #ifndef HAVE_SETEUID
 215 #define seteuid rep_seteuid
 216 int rep_seteuid(uid_t);
 217 #endif
 218
 219 #ifndef HAVE_SETEGID
 220 #define setegid rep_setegid
 221 int rep_setegid(gid_t);
 222 #endif
 223
 224 #if (defined(USE_SETRESUID) && !defined(HAVE_SETRESUID_DECL))
 225 /* stupid glibc */
 226 int setresuid(uid_t ruid, uid_t euid, uid_t suid);
 227 #endif
 228 #if (defined(USE_SETRESUID) && !defined(HAVE_SETRESGID_DECL))
 229 int setresgid(gid_t rgid, gid_t egid, gid_t sgid);
 230 #endif
 231
 232 #ifndef HAVE_CHOWN
 233 #define chown rep_chown
 234 int rep_chown(const char *path, uid_t uid, gid_t gid);
 235 #endif
 236
 237 #ifndef HAVE_CHROOT
 238 #define chroot rep_chroot
 239 int rep_chroot(const char *dirname);
 240 #endif
 241
 242 #ifndef HAVE_LINK
 243 #define link rep_link
 244 int rep_link(const char *oldpath, const char *newpath);
 245 #endif
 246
 247 #ifndef HAVE_READLINK
 248 #define readlink rep_readlink
 249 ssize_t rep_readlink(const char *path, char *buf, size_t bufsize);
 250 #endif
 251
 252 #ifndef HAVE_SYMLINK
 253 #define symlink rep_symlink
 254 int rep_symlink(const char *oldpath, const char *newpath);
 255 #endif
 256
 257 #ifndef HAVE_REALPATH
 258 #define realpath rep_realpath
 259 char *rep_realpath(const char *path, char *resolved_path);
 260 #endif
 261
 262 #ifndef HAVE_LCHOWN
 263 #define lchown rep_lchown
 264 int rep_lchown(const char *fname,uid_t uid,gid_t gid);
 265 #endif
 266
 267 #ifdef HAVE_UNIX_H
 268 #include <unix.h>
 269 #endif
 270
 271 #ifndef HAVE_SETLINEBUF
 272 #define setlinebuf rep_setlinebuf
 273 void rep_setlinebuf(FILE *);
 274 #endif
 275
 276 #ifndef HAVE_STRCASESTR
 277 #define strcasestr rep_strcasestr
 278 char *rep_strcasestr(const char *haystack, const char *needle);
 279 #endif
 280
 281 #ifndef HAVE_STRTOK_R
 282 #define strtok_r rep_strtok_r
 283 char *rep_strtok_r(char *s, const char *delim, char **save_ptr);
 284 #endif
 285
 286 #ifndef HAVE_STRTOLL
 287 #define strtoll rep_strtoll
 288 long long int rep_strtoll(const char *str, char **endptr, int base);
 289 #endif
 290
 291 #ifndef HAVE_STRTOULL
 292 #define strtoull rep_strtoull
 293 unsigned long long int rep_strtoull(const char *str, char **endptr, int base);
 294 #endif
 295
 296 #ifndef HAVE_FTRUNCATE
 297 #define ftruncate rep_ftruncate
 298 int rep_ftruncate(int,off_t);
 299 #endif
 300
 301 #ifndef HAVE_INITGROUPS
 302 #define initgroups rep_initgroups
 303 int rep_initgroups(char *name, gid_t id);
 304 #endif
 305
 306 #if !defined(HAVE_BZERO) && defined(HAVE_MEMSET)
 307 #define bzero(a,b) memset((a),'\0',(b))
 308 #endif
 309
 310 #ifndef HAVE_DLERROR
 311 #define dlerror rep_dlerror
 312 char *rep_dlerror(void);
 313 #endif
 314
 315 #ifndef HAVE_DLOPEN
 316 #define dlopen rep_dlopen
 317 #ifdef DLOPEN_TAKES_UNSIGNED_FLAGS
 318 void *rep_dlopen(const char *name, unsigned int flags);
 319 #else
 320 void *rep_dlopen(const char *name, int flags);
 321 #endif
 322 #endif
 323
 324 #ifndef HAVE_DLSYM
 325 #define dlsym rep_dlsym
 326 void *rep_dlsym(void *handle, const char *symbol);
 327 #endif
 328
 329 #ifndef HAVE_DLCLOSE
 330 #define dlclose rep_dlclose
 331 int rep_dlclose(void *handle);
 332 #endif
 333
 334 #ifndef HAVE_SOCKETPAIR
 335 #define socketpair rep_socketpair
 336 /* prototype is in system/network.h */
 337 #endif
 338
 339 #ifndef HAVE_VDPRINTF
 340 #define vdprintf rep_vdprintf
 341 int rep_vdprintf(int fd, const char *format, va_list ap);
 342 #endif
 343
 344 #ifndef HAVE_DPRINTF
 345 #define dprintf rep_dprintf
 346 int rep_dprintf(int fd, const char *format, ...);
 347 #endif
 348
 349 #ifndef PRINTF_ATTRIBUTE
 350 #if (__GNUC__ >= 3) && (__GNUC_MINOR__ >= 1 )
 351 /** Use gcc attribute to check printf fns.  a1 is the 1-based index of
 352  * the parameter containing the format, and a2 the index of the first
 353  * argument. Note that some gcc 2.x versions don't handle this
 354  * properly **/
 355 #define PRINTF_ATTRIBUTE(a1, a2) __attribute__ ((format (__printf__, a1, a2)))
 356 #else
 357 #define PRINTF_ATTRIBUTE(a1, a2)
 358 #endif
 359 #endif
 360
 361 #ifndef _DEPRECATED_
 362 #if (__GNUC__ >= 3) && (__GNUC_MINOR__ >= 1 )
 363 #define _DEPRECATED_ __attribute__ ((deprecated))
 364 #else
 365 #define _DEPRECATED_
 366 #endif
 367 #endif
 368
 369 #ifndef HAVE_VASPRINTF
 370 #define vasprintf rep_vasprintf
 371 int rep_vasprintf(char **ptr, const char *format, va_list ap) PRINTF_ATTRIBUTE(2,0);
 372 #endif
 373
 374 #if !defined(HAVE_SNPRINTF) || !defined(HAVE_C99_VSNPRINTF)
 375 #define snprintf rep_snprintf
 376 int rep_snprintf(char *,size_t ,const char *, ...) PRINTF_ATTRIBUTE(3,4);
 377 #endif
 378
 379 #if !defined(HAVE_VSNPRINTF) || !defined(HAVE_C99_VSNPRINTF)
 380 #define vsnprintf rep_vsnprintf
 381 int rep_vsnprintf(char *,size_t ,const char *, va_list ap) PRINTF_ATTRIBUTE(3,0);
 382 #endif
 383
 384 #ifndef HAVE_ASPRINTF
 385 #define asprintf rep_asprintf
 386 int rep_asprintf(char **,const char *, ...) PRINTF_ATTRIBUTE(2,3);
 387 #endif
 388
 389 #ifndef HAVE_VSYSLOG
 390 #ifdef HAVE_SYSLOG
 391 #define vsyslog rep_vsyslog
 392 void rep_vsyslog (int facility_priority, const char *format, va_list arglist) PRINTF_ATTRIBUTE(2,0);
 393 #endif
 394 #endif
 395
 396 /* we used to use these fns, but now we have good replacements
 397    for snprintf and vsnprintf */
 398 #define slprintf snprintf
 399
 400
 401 #ifndef HAVE_VA_COPY
 402 #undef va_copy
 403 #ifdef HAVE___VA_COPY
 404 #define va_copy(dest, src) __va_copy(dest, src)
 405 #else
 406 #define va_copy(dest, src) (dest) = (src)
 407 #endif
 408 #endif
 409
 410 #ifndef HAVE_VOLATILE
 411 #define volatile
 412 #endif
 413
 414 #ifndef HAVE_COMPARISON_FN_T
 415 typedef int (*comparison_fn_t)(const void *, const void *);
 416 #endif
 417
 418 #ifdef REPLACE_STRPTIME
 419 #define strptime rep_strptime
 420 struct tm;
 421 char *rep_strptime(const char *buf, const char *format, struct tm *tm);
 422 #endif
 423
 424 #ifndef HAVE_DUP2
 425 #define dup2 rep_dup2
 426 int rep_dup2(int oldfd, int newfd);
 427 #endif
 428
 429 /* Load header file for dynamic linking stuff */
 430 #ifdef HAVE_DLFCN_H
 431 #include <dlfcn.h>
 432 #endif
 433
 434 #ifndef RTLD_LAZY
 435 #define RTLD_LAZY 0
 436 #endif
 437 #ifndef RTLD_NOW
 438 #define RTLD_NOW 0
 439 #endif
 440 #ifndef RTLD_GLOBAL
 441 #define RTLD_GLOBAL 0
 442 #endif
 443
 444 #ifndef HAVE_SECURE_MKSTEMP
 445 #define mkstemp(path) rep_mkstemp(path)
 446 int rep_mkstemp(char *temp);
 447 #endif
 448
 449 #ifndef HAVE_MKDTEMP
 450 #define mkdtemp rep_mkdtemp
 451 char *rep_mkdtemp(char *template);
 452 #endif
 453
 454 #ifndef HAVE_PREAD
 455 #define pread rep_pread
 456 ssize_t rep_pread(int __fd, void *__buf, size_t __nbytes, off_t __offset);
 457 #define LIBREPLACE_PREAD_REPLACED 1
 458 #else
 459 #define LIBREPLACE_PREAD_NOT_REPLACED 1
 460 #endif
 461
 462 #ifndef HAVE_PWRITE
 463 #define pwrite rep_pwrite
 464 ssize_t rep_pwrite(int __fd, const void *__buf, size_t __nbytes, off_t __offset);
 465 #define LIBREPLACE_PWRITE_REPLACED 1
 466 #else
 467 #define LIBREPLACE_PWRITE_NOT_REPLACED 1
 468 #endif
 469
 470 #if !defined(HAVE_INET_NTOA) || defined(REPLACE_INET_NTOA)
 471 #define inet_ntoa rep_inet_ntoa
 472 /* prototype is in "system/network.h" */
 473 #endif
 474
 475 #ifndef HAVE_INET_PTON
 476 #define inet_pton rep_inet_pton
 477 /* prototype is in "system/network.h" */
 478 #endif
 479
 480 #ifndef HAVE_INET_NTOP
 481 #define inet_ntop rep_inet_ntop
 482 /* prototype is in "system/network.h" */
 483 #endif
 484
 485 #ifndef HAVE_INET_ATON
 486 #define inet_aton rep_inet_aton
 487 /* prototype is in "system/network.h" */
 488 #endif
 489
 490 #ifndef HAVE_CONNECT
 491 #define connect rep_connect
 492 /* prototype is in "system/network.h" */
 493 #endif
 494
 495 #ifndef HAVE_GETHOSTBYNAME
 496 #define gethostbyname rep_gethostbyname
 497 /* prototype is in "system/network.h" */
 498 #endif
 499
 500 #ifndef HAVE_GETIFADDRS
 501 #define getifaddrs rep_getifaddrs
 502 /* prototype is in "system/network.h" */
 503 #endif
 504
 505 #ifndef HAVE_FREEIFADDRS
 506 #define freeifaddrs rep_freeifaddrs
 507 /* prototype is in "system/network.h" */
 508 #endif
 509
 510 #ifndef HAVE_GET_CURRENT_DIR_NAME
 511 #define get_current_dir_name rep_get_current_dir_name
 512 char *rep_get_current_dir_name(void);
 513 #endif
 514
 515 #if !defined(HAVE_STRERROR_R) || !defined(STRERROR_R_PROTO_COMPATIBLE)
 516 #undef strerror_r
 517 #define strerror_r rep_strerror_r
 518 int rep_strerror_r(int errnum, char *buf, size_t buflen);
 519 #endif
 520
 521 #if !defined(HAVE_CLOCK_GETTIME)
 522 #define clock_gettime rep_clock_gettime
 523 #endif
 524
 525 #ifdef HAVE_LIMITS_H
 526 #include <limits.h>
 527 #endif
 528
 529 #ifdef HAVE_SYS_PARAM_H
 530 #include <sys/param.h>
 531 #endif
 532
 533 /* The extra casts work around common compiler bugs.  */
 534 #define _TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
 535 /* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
 536    It is necessary at least when t == time_t.  */
 537 #define _TYPE_MINIMUM(t) ((t) (_TYPE_SIGNED (t) \
 538                               ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
 539 #define _TYPE_MAXIMUM(t) ((t) (~ (t) 0 - _TYPE_MINIMUM (t)))
 540
 541 #ifndef UINT16_MAX
 542 #define UINT16_MAX 65535
 543 #endif
 544
 545 #ifndef UINT32_MAX
 546 #define UINT32_MAX (4294967295U)
 547 #endif
 548
 549 #ifndef UINT64_MAX
 550 #define UINT64_MAX ((uint64_t)-1)
 551 #endif
 552
 553 #ifndef CHAR_BIT
 554 #define CHAR_BIT 8
 555 #endif
 556
 557 #ifndef INT32_MAX
 558 #define INT32_MAX _TYPE_MAXIMUM(int32_t)
 559 #endif
 560
 561 #ifdef HAVE_STDBOOL_H
 562 #include <stdbool.h>
 563 #endif
 564
 565 #if !defined(HAVE_BOOL)
 566 #ifdef HAVE__Bool
 567 #define bool _Bool
 568 #else
 569 typedef int bool;
 570 #endif
 571 #endif
 572
 573 #if !defined(HAVE_INTPTR_T)
 574 typedef long long intptr_t ;
 575 #endif
 576
 577 #if !defined(HAVE_UINTPTR_T)
 578 typedef unsigned long long uintptr_t ;
 579 #endif
 580
 581 #if !defined(HAVE_PTRDIFF_T)
 582 typedef unsigned long long ptrdiff_t ;
 583 #endif
 584
 585 /*
 586  * to prevent <rpcsvc/yp_prot.h> from doing a redefine of 'bool'
 587  *
 588  * IRIX, HPUX, MacOS 10 and Solaris need BOOL_DEFINED
 589  * Tru64 needs _BOOL_EXISTS
 590  * AIX needs _BOOL,_TRUE,_FALSE
 591  */
 592 #ifndef BOOL_DEFINED
 593 #define BOOL_DEFINED
 594 #endif
 595 #ifndef _BOOL_EXISTS
 596 #define _BOOL_EXISTS
 597 #endif
 598 #ifndef _BOOL
 599 #define _BOOL
 600 #endif
 601
 602 #ifndef __bool_true_false_are_defined
 603 #define __bool_true_false_are_defined
 604 #endif
 605
 606 #ifndef true
 607 #define true (1)
 608 #endif
 609 #ifndef false
 610 #define false (0)
 611 #endif
 612
 613 #ifndef _TRUE
 614 #define _TRUE true
 615 #endif
 616 #ifndef _FALSE
 617 #define _FALSE false
 618 #endif
 619
 620 #ifndef HAVE_FUNCTION_MACRO
 621 #ifdef HAVE_func_MACRO
 622 #define __FUNCTION__ __func__
 623 #else
 624 #define __FUNCTION__ ("")
 625 #endif
 626 #endif
 627
 628
 629 #ifndef MIN
 630 #define MIN(a,b) ((a)<(b)?(a):(b))
 631 #endif
 632
 633 #ifndef MAX
 634 #define MAX(a,b) ((a)>(b)?(a):(b))
 635 #endif
 636
 637 #if !defined(HAVE_VOLATILE)
 638 #define volatile
 639 #endif
 640
 641 /**
 642   this is a warning hack. The idea is to use this everywhere that we
 643   get the "discarding const" warning from gcc. That doesn't actually
 644   fix the problem of course, but it means that when we do get to
 645   cleaning them up we can do it by searching the code for
 646   discard_const.
 647
 648   It also means that other error types aren't as swamped by the noise
 649   of hundreds of const warnings, so we are more likely to notice when
 650   we get new errors.
 651
 652   Please only add more uses of this macro when you find it
 653   _really_ hard to fix const warnings. Our aim is to eventually use
 654   this function in only a very few places.
 655
 656   Also, please call this via the discard_const_p() macro interface, as that
 657   makes the return type safe.
 658 */
 659 #define discard_const(ptr) ((void *)((uintptr_t)(ptr)))
 660
 661 /** Type-safe version of discard_const */
 662 #define discard_const_p(type, ptr) ((type *)discard_const(ptr))
 663
 664 #ifndef __STRING
 665 #define __STRING(x)    #x
 666 #endif
 667
 668 #ifndef __STRINGSTRING
 669 #define __STRINGSTRING(x) __STRING(x)
 670 #endif
 671
 672 #ifndef __LINESTR__
 673 #define __LINESTR__ __STRINGSTRING(__LINE__)
 674 #endif
 675
 676 #ifndef __location__
 677 #define __location__ __FILE__ ":" __LINESTR__
 678 #endif
 679
 680 /**
 681  * zero a structure
 682  */
 683 #define ZERO_STRUCT(x) memset((char *)&(x), 0, sizeof(x))
 684
 685 /**
 686  * zero a structure given a pointer to the structure
 687  */
 688 #define ZERO_STRUCTP(x) do { if ((x) != NULL) memset((char *)(x), 0, sizeof(*(x))); } while(0)
 689
 690 /**
 691  * zero a structure given a pointer to the structure - no zero check
 692  */
 693 #define ZERO_STRUCTPN(x) memset((char *)(x), 0, sizeof(*(x)))
 694
 695 /* zero an array - note that sizeof(array) must work - ie. it must not be a
 696    pointer */
 697 #define ZERO_ARRAY(x) memset((char *)(x), 0, sizeof(x))
 698
 699 /**
 700  * work out how many elements there are in a static array
 701  */
 702 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
 703
 704 /**
 705  * pointer difference macro
 706  */
 707 #define PTR_DIFF(p1,p2) ((ptrdiff_t)(((const char *)(p1)) - (const char *)(p2)))
 708
 709 #if MMAP_BLACKLIST
 710 #undef HAVE_MMAP
 711 #endif
 712
 713 #ifdef __COMPAR_FN_T
 714 #define QSORT_CAST (__compar_fn_t)
 715 #endif
 716
 717 #ifndef QSORT_CAST
 718 #define QSORT_CAST (int (*)(const void *, const void *))
 719 #endif
 720
 721 #ifndef PATH_MAX
 722 #define PATH_MAX 1024
 723 #endif
 724
 725 #ifndef MAX_DNS_NAME_LENGTH
 726 #define MAX_DNS_NAME_LENGTH 256 /* Actually 255 but +1 for terminating null. */
 727 #endif
 728
 729 #ifndef HAVE_CRYPT
 730 char *ufc_crypt(const char *key, const char *salt);
 731 #define crypt ufc_crypt
 732 #else
 733 #ifdef HAVE_CRYPT_H
 734 #include <crypt.h>
 735 #endif
 736 #endif
 737
 738 /* these macros gain us a few percent of speed on gcc */
 739 #if (__GNUC__ >= 3)
 740 /* the strange !! is to ensure that __builtin_expect() takes either 0 or 1
 741    as its first argument */
 742 #ifndef likely
 743 #define likely(x)   __builtin_expect(!!(x), 1)
 744 #endif
 745 #ifndef unlikely
 746 #define unlikely(x) __builtin_expect(!!(x), 0)
 747 #endif
 748 #else
 749 #ifndef likely
 750 #define likely(x) (x)
 751 #endif
 752 #ifndef unlikely
 753 #define unlikely(x) (x)
 754 #endif
 755 #endif
 756
 757 #ifndef HAVE_FDATASYNC
 758 #define fdatasync(fd) fsync(fd)
 759 #endif
 760
 761 /* these are used to mark symbols as local to a shared lib, or
 762  * publicly available via the shared lib API */
 763 #ifndef _PUBLIC_
 764 #ifdef HAVE_VISIBILITY_ATTR
 765 #define _PUBLIC_ __attribute__((visibility("default")))
 766 #else
 767 #define _PUBLIC_
 768 #endif
 769 #endif
 770
 771 #ifndef _PRIVATE_
 772 #ifdef HAVE_VISIBILITY_ATTR
 773 #  define _PRIVATE_ __attribute__((visibility("hidden")))
 774 #else
 775 #  define _PRIVATE_
 776 #endif
 777 #endif
 778
 779 #endif /* _LIBREPLACE_REPLACE_H */