external/bsd/libevent/dist/include/event2/util.h

   1 /*      $NetBSD: util.h,v 1.3 2015/01/29 07:26:02 spz Exp $     */
   2 /*
   3  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27 #ifndef _EVENT2_UTIL_H_
  28 #define _EVENT2_UTIL_H_
  29
  30 /** @file event2/util.h
  31
  32   Common convenience functions for cross-platform portability and
  33   related socket manipulations.
  34
  35  */
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 #include <event2/event-config.h>
  42 #ifdef _EVENT_HAVE_SYS_TIME_H
  43 #include <sys/time.h>
  44 #endif
  45 #ifdef _EVENT_HAVE_STDINT_H
  46 #include <stdint.h>
  47 #elif defined(_EVENT_HAVE_INTTYPES_H)
  48 #include <inttypes.h>
  49 #endif
  50 #ifdef _EVENT_HAVE_SYS_TYPES_H
  51 #include <sys/types.h>
  52 #endif
  53 #ifdef _EVENT_HAVE_STDDEF_H
  54 #include <stddef.h>
  55 #endif
  56 #ifdef _MSC_VER
  57 #include <BaseTsd.h>
  58 #endif
  59 #include <stdarg.h>
  60 #ifdef _EVENT_HAVE_NETDB_H
  61 #if !defined(_GNU_SOURCE)
  62 #define _GNU_SOURCE
  63 #endif
  64 #include <netdb.h>
  65 #endif
  66
  67 #ifdef WIN32
  68 #include <winsock2.h>
  69 #else
  70 #include <sys/socket.h>
  71 #endif
  72
  73 /* Some openbsd autoconf versions get the name of this macro wrong. */
  74 #if defined(_EVENT_SIZEOF_VOID__) && !defined(_EVENT_SIZEOF_VOID_P)
  75 #define _EVENT_SIZEOF_VOID_P _EVENT_SIZEOF_VOID__
  76 #endif
  77
  78 /**
  79  * @name Standard integer types.
  80  *
  81  * Integer type definitions for types that are supposed to be defined in the
  82  * C99-specified stdint.h.  Shamefully, some platforms do not include
  83  * stdint.h, so we need to replace it.  (If you are on a platform like this,
  84  * your C headers are now over 10 years out of date.  You should bug them to
  85  * do something about this.)
  86  *
  87  * We define:
  88  *
  89  * <dl>
  90  *   <dt>ev_uint64_t, ev_uint32_t, ev_uint16_t, ev_uint8_t</dt>
  91  *      <dd>unsigned integer types of exactly 64, 32, 16, and 8 bits
  92  *          respectively.</dd>
  93  *    <dt>ev_int64_t, ev_int32_t, ev_int16_t, ev_int8_t</dt>
  94  *      <dd>signed integer types of exactly 64, 32, 16, and 8 bits
  95  *          respectively.</dd>
  96  *    <dt>ev_uintptr_t, ev_intptr_t</dt>
  97  *      <dd>unsigned/signed integers large enough
  98  *      to hold a pointer without loss of bits.</dd>
  99  *    <dt>ev_ssize_t</dt>
 100  *      <dd>A signed type of the same size as size_t</dd>
 101  *    <dt>ev_off_t</dt>
 102  *      <dd>A signed type typically used to represent offsets within a
 103  *      (potentially large) file</dd>
 104  *
 105  * @{
 106  */
 107 #ifdef _EVENT_HAVE_UINT64_T
 108 #define ev_uint64_t uint64_t
 109 #define ev_int64_t int64_t
 110 #elif defined(WIN32)
 111 #define ev_uint64_t unsigned __int64
 112 #define ev_int64_t signed __int64
 113 #elif _EVENT_SIZEOF_LONG_LONG == 8
 114 #define ev_uint64_t unsigned long long
 115 #define ev_int64_t long long
 116 #elif _EVENT_SIZEOF_LONG == 8
 117 #define ev_uint64_t unsigned long
 118 #define ev_int64_t long
 119 #elif defined(_EVENT_IN_DOXYGEN)
 120 #define ev_uint64_t ...
 121 #define ev_int64_t ...
 122 #else
 123 #error "No way to define ev_uint64_t"
 124 #endif
 125
 126 #ifdef _EVENT_HAVE_UINT32_T
 127 #define ev_uint32_t uint32_t
 128 #define ev_int32_t int32_t
 129 #elif defined(WIN32)
 130 #define ev_uint32_t unsigned int
 131 #define ev_int32_t signed int
 132 #elif _EVENT_SIZEOF_LONG == 4
 133 #define ev_uint32_t unsigned long
 134 #define ev_int32_t signed long
 135 #elif _EVENT_SIZEOF_INT == 4
 136 #define ev_uint32_t unsigned int
 137 #define ev_int32_t signed int
 138 #elif defined(_EVENT_IN_DOXYGEN)
 139 #define ev_uint32_t ...
 140 #define ev_int32_t ...
 141 #else
 142 #error "No way to define ev_uint32_t"
 143 #endif
 144
 145 #ifdef _EVENT_HAVE_UINT16_T
 146 #define ev_uint16_t uint16_t
 147 #define ev_int16_t  int16_t
 148 #elif defined(WIN32)
 149 #define ev_uint16_t unsigned short
 150 #define ev_int16_t  signed short
 151 #elif _EVENT_SIZEOF_INT == 2
 152 #define ev_uint16_t unsigned int
 153 #define ev_int16_t  signed int
 154 #elif _EVENT_SIZEOF_SHORT == 2
 155 #define ev_uint16_t unsigned short
 156 #define ev_int16_t  signed short
 157 #elif defined(_EVENT_IN_DOXYGEN)
 158 #define ev_uint16_t ...
 159 #define ev_int16_t ...
 160 #else
 161 #error "No way to define ev_uint16_t"
 162 #endif
 163
 164 #ifdef _EVENT_HAVE_UINT8_T
 165 #define ev_uint8_t uint8_t
 166 #define ev_int8_t int8_t
 167 #elif defined(_EVENT_IN_DOXYGEN)
 168 #define ev_uint8_t ...
 169 #define ev_int8_t ...
 170 #else
 171 #define ev_uint8_t unsigned char
 172 #define ev_int8_t signed char
 173 #endif
 174
 175 #ifdef _EVENT_HAVE_UINTPTR_T
 176 #define ev_uintptr_t uintptr_t
 177 #define ev_intptr_t intptr_t
 178 #elif _EVENT_SIZEOF_VOID_P <= 4
 179 #define ev_uintptr_t ev_uint32_t
 180 #define ev_intptr_t ev_int32_t
 181 #elif _EVENT_SIZEOF_VOID_P <= 8
 182 #define ev_uintptr_t ev_uint64_t
 183 #define ev_intptr_t ev_int64_t
 184 #elif defined(_EVENT_IN_DOXYGEN)
 185 #define ev_uintptr_t ...
 186 #define ev_intptr_t ...
 187 #else
 188 #error "No way to define ev_uintptr_t"
 189 #endif
 190
 191 #ifdef _EVENT_ssize_t
 192 #define ev_ssize_t _EVENT_ssize_t
 193 #else
 194 #define ev_ssize_t ssize_t
 195 #endif
 196
 197 #ifdef WIN32
 198 #define ev_off_t ev_int64_t
 199 #else
 200 #define ev_off_t off_t
 201 #endif
 202 /**@}*/
 203
 204 /* Limits for integer types.
 205
 206    We're making two assumptions here:
 207      - The compiler does constant folding properly.
 208      - The platform does signed arithmetic in two's complement.
 209 */
 210
 211 /**
 212    @name Limits for integer types
 213
 214    These macros hold the largest or smallest values possible for the
 215    ev_[u]int*_t types.
 216
 217    @{
 218 */
 219 #define EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) | 0xffffffffUL)
 220 #define EV_INT64_MAX  ((((ev_int64_t) 0x7fffffffL) << 32) | 0xffffffffL)
 221 #define EV_INT64_MIN  ((-EV_INT64_MAX) - 1)
 222 #define EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL)
 223 #define EV_INT32_MAX  ((ev_int32_t) 0x7fffffffL)
 224 #define EV_INT32_MIN  ((-EV_INT32_MAX) - 1)
 225 #define EV_UINT16_MAX ((ev_uint16_t)0xffffUL)
 226 #define EV_INT16_MAX  ((ev_int16_t) 0x7fffL)
 227 #define EV_INT16_MIN  ((-EV_INT16_MAX) - 1)
 228 #define EV_UINT8_MAX  255
 229 #define EV_INT8_MAX   127
 230 #define EV_INT8_MIN   ((-EV_INT8_MAX) - 1)
 231 /** @} */
 232
 233 /**
 234    @name Limits for SIZE_T and SSIZE_T
 235
 236    @{
 237 */
 238 #if _EVENT_SIZEOF_SIZE_T == 8
 239 #define EV_SIZE_MAX EV_UINT64_MAX
 240 #define EV_SSIZE_MAX EV_INT64_MAX
 241 #elif _EVENT_SIZEOF_SIZE_T == 4
 242 #define EV_SIZE_MAX EV_UINT32_MAX
 243 #define EV_SSIZE_MAX EV_INT32_MAX
 244 #elif defined(_EVENT_IN_DOXYGEN)
 245 #define EV_SIZE_MAX ...
 246 #define EV_SSIZE_MAX ...
 247 #else
 248 #error "No way to define SIZE_MAX"
 249 #endif
 250
 251 #define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1)
 252 /**@}*/
 253
 254 #ifdef WIN32
 255 #define ev_socklen_t int
 256 #elif defined(_EVENT_socklen_t)
 257 #define ev_socklen_t _EVENT_socklen_t
 258 #else
 259 #define ev_socklen_t socklen_t
 260 #endif
 261
 262 #ifdef _EVENT_HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY
 263 #if !defined(_EVENT_HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY) \
 264  && !defined(ss_family)
 265 #define ss_family __ss_family
 266 #endif
 267 #endif
 268
 269 /**
 270  * A type wide enough to hold the output of "socket()" or "accept()".  On
 271  * Windows, this is an intptr_t; elsewhere, it is an int. */
 272 #ifdef WIN32
 273 #define evutil_socket_t intptr_t
 274 #else
 275 #define evutil_socket_t int
 276 #endif
 277
 278 /** Create two new sockets that are connected to each other.
 279
 280     On Unix, this simply calls socketpair().  On Windows, it uses the
 281     loopback network interface on 127.0.0.1, and only
 282     AF_INET,SOCK_STREAM are supported.
 283
 284     (This may fail on some Windows hosts where firewall software has cleverly
 285     decided to keep 127.0.0.1 from talking to itself.)
 286
 287     Parameters and return values are as for socketpair()
 288 */
 289 int evutil_socketpair(int d, int type, int protocol, evutil_socket_t sv[2]);
 290 /** Do platform-specific operations as needed to make a socket nonblocking.
 291
 292     @param sock The socket to make nonblocking
 293     @return 0 on success, -1 on failure
 294  */
 295 int evutil_make_socket_nonblocking(evutil_socket_t sock);
 296
 297 /** Do platform-specific operations to make a listener socket reusable.
 298
 299     Specifically, we want to make sure that another program will be able
 300     to bind this address right after we've closed the listener.
 301
 302     This differs from Windows's interpretation of "reusable", which
 303     allows multiple listeners to bind the same address at the same time.
 304
 305     @param sock The socket to make reusable
 306     @return 0 on success, -1 on failure
 307  */
 308 int evutil_make_listen_socket_reuseable(evutil_socket_t sock);
 309
 310 /** Do platform-specific operations as needed to close a socket upon a
 311     successful execution of one of the exec*() functions.
 312
 313     @param sock The socket to be closed
 314     @return 0 on success, -1 on failure
 315  */
 316 int evutil_make_socket_closeonexec(evutil_socket_t sock);
 317
 318 /** Do the platform-specific call needed to close a socket returned from
 319     socket() or accept().
 320
 321     @param sock The socket to be closed
 322     @return 0 on success, -1 on failure
 323  */
 324 int evutil_closesocket(evutil_socket_t sock);
 325 #define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s)
 326
 327
 328 #ifdef WIN32
 329 /** Return the most recent socket error.  Not idempotent on all platforms. */
 330 #define EVUTIL_SOCKET_ERROR() WSAGetLastError()
 331 /** Replace the most recent socket error with errcode */
 332 #define EVUTIL_SET_SOCKET_ERROR(errcode)                \
 333         do { WSASetLastError(errcode); } while (0)
 334 /** Return the most recent socket error to occur on sock. */
 335 int evutil_socket_geterror(evutil_socket_t sock);
 336 /** Convert a socket error to a string. */
 337 const char *evutil_socket_error_to_string(int errcode);
 338 #elif defined(_EVENT_IN_DOXYGEN)
 339 /**
 340    @name Socket error functions
 341
 342    These functions are needed for making programs compatible between
 343    Windows and Unix-like platforms.
 344
 345    You see, Winsock handles socket errors differently from the rest of
 346    the world.  Elsewhere, a socket error is like any other error and is
 347    stored in errno.  But winsock functions require you to retrieve the
 348    error with a special function, and don't let you use strerror for
 349    the error codes.  And handling EWOULDBLOCK is ... different.
 350
 351    @{
 352 */
 353 /** Return the most recent socket error.  Not idempotent on all platforms. */
 354 #define EVUTIL_SOCKET_ERROR() ...
 355 /** Replace the most recent socket error with errcode */
 356 #define EVUTIL_SET_SOCKET_ERROR(errcode) ...
 357 /** Return the most recent socket error to occur on sock. */
 358 #define evutil_socket_geterror(sock) ...
 359 /** Convert a socket error to a string. */
 360 #define evutil_socket_error_to_string(errcode) ...
 361 /**@}*/
 362 #else
 363 #define EVUTIL_SOCKET_ERROR() (errno)
 364 #define EVUTIL_SET_SOCKET_ERROR(errcode)                \
 365                 do { errno = (errcode); } while (0)
 366 #define evutil_socket_geterror(sock) (errno)
 367 #define evutil_socket_error_to_string(errcode) (strerror(errcode))
 368 #endif
 369
 370
 371 /**
 372  * @name Manipulation macros for struct timeval.
 373  *
 374  * We define replacements
 375  * for timeradd, timersub, timerclear, timercmp, and timerisset.
 376  *
 377  * @{
 378  */
 379 #ifdef _EVENT_HAVE_TIMERADD
 380 #define evutil_timeradd(tvp, uvp, vvp) timeradd((tvp), (uvp), (vvp))
 381 #define evutil_timersub(tvp, uvp, vvp) timersub((tvp), (uvp), (vvp))
 382 #else
 383 #define evutil_timeradd(tvp, uvp, vvp)                                  \
 384         do {                                                            \
 385                 (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec;          \
 386                 (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec;       \
 387                 if ((vvp)->tv_usec >= 1000000) {                        \
 388                         (vvp)->tv_sec++;                                \
 389                         (vvp)->tv_usec -= 1000000;                      \
 390                 }                                                       \
 391         } while (0)
 392 #define evutil_timersub(tvp, uvp, vvp)                                  \
 393         do {                                                            \
 394                 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;          \
 395                 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec;       \
 396                 if ((vvp)->tv_usec < 0) {                               \
 397                         (vvp)->tv_sec--;                                \
 398                         (vvp)->tv_usec += 1000000;                      \
 399                 }                                                       \
 400         } while (0)
 401 #endif /* !_EVENT_HAVE_HAVE_TIMERADD */
 402
 403 #ifdef _EVENT_HAVE_TIMERCLEAR
 404 #define evutil_timerclear(tvp) timerclear(tvp)
 405 #else
 406 #define evutil_timerclear(tvp)  (tvp)->tv_sec = (tvp)->tv_usec = 0
 407 #endif
 408 /**@}*/
 409
 410 /** Return true iff the tvp is related to uvp according to the relational
 411  * operator cmp.  Recognized values for cmp are ==, <=, <, >=, and >. */
 412 #define evutil_timercmp(tvp, uvp, cmp)                                  \
 413         (((tvp)->tv_sec == (uvp)->tv_sec) ?                             \
 414          ((tvp)->tv_usec cmp (uvp)->tv_usec) :                          \
 415          ((tvp)->tv_sec cmp (uvp)->tv_sec))
 416
 417 #ifdef _EVENT_HAVE_TIMERISSET
 418 #define evutil_timerisset(tvp) timerisset(tvp)
 419 #else
 420 #define evutil_timerisset(tvp)  ((tvp)->tv_sec || (tvp)->tv_usec)
 421 #endif
 422
 423 /** Replacement for offsetof on platforms that don't define it. */
 424 #ifdef offsetof
 425 #define evutil_offsetof(type, field) offsetof(type, field)
 426 #else
 427 #define evutil_offsetof(type, field) ((off_t)(&((type *)0)->field))
 428 #endif
 429
 430 /* big-int related functions */
 431 /** Parse a 64-bit value from a string.  Arguments are as for strtol. */
 432 ev_int64_t evutil_strtoll(const char *s, char **endptr, int base);
 433
 434 /** Replacement for gettimeofday on platforms that lack it. */
 435 #ifdef _EVENT_HAVE_GETTIMEOFDAY
 436 #define evutil_gettimeofday(tv, tz) gettimeofday((tv), (tz))
 437 #else
 438 struct timezone;
 439 int evutil_gettimeofday(struct timeval *tv, struct timezone *tz);
 440 #endif
 441
 442 /** Replacement for snprintf to get consistent behavior on platforms for
 443     which the return value of snprintf does not conform to C99.
 444  */
 445 int evutil_snprintf(char *buf, size_t buflen, const char *format, ...)
 446 #ifdef __GNUC__
 447         __attribute__((format(printf, 3, 4)))
 448 #endif
 449 ;
 450 /** Replacement for vsnprintf to get consistent behavior on platforms for
 451     which the return value of snprintf does not conform to C99.
 452  */
 453 int evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap)
 454 #ifdef __GNUC__
 455         __attribute__((format(printf, 3, 0)))
 456 #endif
 457 ;
 458
 459 /** Replacement for inet_ntop for platforms which lack it. */
 460 const char *evutil_inet_ntop(int af, const void *src, char *dst, size_t len);
 461 /** Replacement for inet_pton for platforms which lack it. */
 462 int evutil_inet_pton(int af, const char *src, void *dst);
 463 struct sockaddr;
 464
 465 /** Parse an IPv4 or IPv6 address, with optional port, from a string.
 466
 467     Recognized formats are:
 468     - [IPv6Address]:port
 469     - [IPv6Address]
 470     - IPv6Address
 471     - IPv4Address:port
 472     - IPv4Address
 473
 474     If no port is specified, the port in the output is set to 0.
 475
 476     @param str The string to parse.
 477     @param out A struct sockaddr to hold the result.  This should probably be
 478        a struct sockaddr_storage.
 479     @param outlen A pointer to the number of bytes that that 'out' can safely
 480        hold.  Set to the number of bytes used in 'out' on success.
 481     @return -1 if the address is not well-formed, if the port is out of range,
 482        or if out is not large enough to hold the result.  Otherwise returns
 483        0 on success.
 484 */
 485 int evutil_parse_sockaddr_port(const char *str, struct sockaddr *out, int *outlen);
 486
 487 /** Compare two sockaddrs; return 0 if they are equal, or less than 0 if sa1
 488  * preceeds sa2, or greater than 0 if sa1 follows sa2.  If include_port is
 489  * true, consider the port as well as the address.  Only implemented for
 490  * AF_INET and AF_INET6 addresses. The ordering is not guaranteed to remain
 491  * the same between Libevent versions. */
 492 int evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2,
 493     int include_port);
 494
 495 /** As strcasecmp, but always compares the characters in locale-independent
 496     ASCII.  That's useful if you're handling data in ASCII-based protocols.
 497  */
 498 int evutil_ascii_strcasecmp(const char *str1, const char *str2);
 499 /** As strncasecmp, but always compares the characters in locale-independent
 500     ASCII.  That's useful if you're handling data in ASCII-based protocols.
 501  */
 502 int evutil_ascii_strncasecmp(const char *str1, const char *str2, size_t n);
 503
 504 /* Here we define evutil_addrinfo to the native addrinfo type, or redefine it
 505  * if this system has no getaddrinfo(). */
 506 #ifdef _EVENT_HAVE_STRUCT_ADDRINFO
 507 #define evutil_addrinfo addrinfo
 508 #else
 509 /** A definition of struct addrinfo for systems that lack it.
 510
 511     (This is just an alias for struct addrinfo if the system defines
 512     struct addrinfo.)
 513 */
 514 struct evutil_addrinfo {
 515         int     ai_flags;     /* AI_PASSIVE, AI_CANONNAME, AI_NUMERICHOST */
 516         int     ai_family;    /* PF_xxx */
 517         int     ai_socktype;  /* SOCK_xxx */
 518         int     ai_protocol;  /* 0 or IPPROTO_xxx for IPv4 and IPv6 */
 519         size_t  ai_addrlen;   /* length of ai_addr */
 520         char   *ai_canonname; /* canonical name for nodename */
 521         struct sockaddr  *ai_addr; /* binary address */
 522         struct evutil_addrinfo  *ai_next; /* next structure in linked list */
 523 };
 524 #endif
 525 /** @name evutil_getaddrinfo() error codes
 526
 527     These values are possible error codes for evutil_getaddrinfo() and
 528     related functions.
 529
 530     @{
 531 */
 532 #ifdef EAI_ADDRFAMILY
 533 #define EVUTIL_EAI_ADDRFAMILY EAI_ADDRFAMILY
 534 #else
 535 #define EVUTIL_EAI_ADDRFAMILY -901
 536 #endif
 537 #ifdef EAI_AGAIN
 538 #define EVUTIL_EAI_AGAIN EAI_AGAIN
 539 #else
 540 #define EVUTIL_EAI_AGAIN -902
 541 #endif
 542 #ifdef EAI_BADFLAGS
 543 #define EVUTIL_EAI_BADFLAGS EAI_BADFLAGS
 544 #else
 545 #define EVUTIL_EAI_BADFLAGS -903
 546 #endif
 547 #ifdef EAI_FAIL
 548 #define EVUTIL_EAI_FAIL EAI_FAIL
 549 #else
 550 #define EVUTIL_EAI_FAIL -904
 551 #endif
 552 #ifdef EAI_FAMILY
 553 #define EVUTIL_EAI_FAMILY EAI_FAMILY
 554 #else
 555 #define EVUTIL_EAI_FAMILY -905
 556 #endif
 557 #ifdef EAI_MEMORY
 558 #define EVUTIL_EAI_MEMORY EAI_MEMORY
 559 #else
 560 #define EVUTIL_EAI_MEMORY -906
 561 #endif
 562 /* This test is a bit complicated, since some MS SDKs decide to
 563  * remove NODATA or redefine it to be the same as NONAME, in a
 564  * fun interpretation of RFC 2553 and RFC 3493. */
 565 #if defined(EAI_NODATA) && (!defined(EAI_NONAME) || EAI_NODATA != EAI_NONAME)
 566 #define EVUTIL_EAI_NODATA EAI_NODATA
 567 #else
 568 #define EVUTIL_EAI_NODATA -907
 569 #endif
 570 #ifdef EAI_NONAME
 571 #define EVUTIL_EAI_NONAME EAI_NONAME
 572 #else
 573 #define EVUTIL_EAI_NONAME -908
 574 #endif
 575 #ifdef EAI_SERVICE
 576 #define EVUTIL_EAI_SERVICE EAI_SERVICE
 577 #else
 578 #define EVUTIL_EAI_SERVICE -909
 579 #endif
 580 #ifdef EAI_SOCKTYPE
 581 #define EVUTIL_EAI_SOCKTYPE EAI_SOCKTYPE
 582 #else
 583 #define EVUTIL_EAI_SOCKTYPE -910
 584 #endif
 585 #ifdef EAI_SYSTEM
 586 #define EVUTIL_EAI_SYSTEM EAI_SYSTEM
 587 #else
 588 #define EVUTIL_EAI_SYSTEM -911
 589 #endif
 590
 591 #define EVUTIL_EAI_CANCEL -90001
 592
 593 #ifdef AI_PASSIVE
 594 #define EVUTIL_AI_PASSIVE AI_PASSIVE
 595 #else
 596 #define EVUTIL_AI_PASSIVE 0x1000
 597 #endif
 598 #ifdef AI_CANONNAME
 599 #define EVUTIL_AI_CANONNAME AI_CANONNAME
 600 #else
 601 #define EVUTIL_AI_CANONNAME 0x2000
 602 #endif
 603 #ifdef AI_NUMERICHOST
 604 #define EVUTIL_AI_NUMERICHOST AI_NUMERICHOST
 605 #else
 606 #define EVUTIL_AI_NUMERICHOST 0x4000
 607 #endif
 608 #ifdef AI_NUMERICSERV
 609 #define EVUTIL_AI_NUMERICSERV AI_NUMERICSERV
 610 #else
 611 #define EVUTIL_AI_NUMERICSERV 0x8000
 612 #endif
 613 #ifdef AI_V4MAPPED
 614 #define EVUTIL_AI_V4MAPPED AI_V4MAPPED
 615 #else
 616 #define EVUTIL_AI_V4MAPPED 0x10000
 617 #endif
 618 #ifdef AI_ALL
 619 #define EVUTIL_AI_ALL AI_ALL
 620 #else
 621 #define EVUTIL_AI_ALL 0x20000
 622 #endif
 623 #ifdef AI_ADDRCONFIG
 624 #define EVUTIL_AI_ADDRCONFIG AI_ADDRCONFIG
 625 #else
 626 #define EVUTIL_AI_ADDRCONFIG 0x40000
 627 #endif
 628 /**@}*/
 629
 630 struct evutil_addrinfo;
 631 /**
 632  * This function clones getaddrinfo for systems that don't have it.  For full
 633  * details, see RFC 3493, section 6.1.
 634  *
 635  * Limitations:
 636  * - When the system has no getaddrinfo, we fall back to gethostbyname_r or
 637  *   gethostbyname, with their attendant issues.
 638  * - The AI_V4MAPPED and AI_ALL flags are not currently implemented.
 639  *
 640  * For a nonblocking variant, see evdns_getaddrinfo.
 641  */
 642 int evutil_getaddrinfo(const char *nodename, const char *servname,
 643     const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res);
 644
 645 /** Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo. */
 646 void evutil_freeaddrinfo(struct evutil_addrinfo *ai);
 647
 648 const char *evutil_gai_strerror(int err);
 649
 650 /** Generate n bytes of secure pseudorandom data, and store them in buf.
 651  *
 652  * Current versions of Libevent use an ARC4-based random number generator,
 653  * seeded using the platform's entropy source (/dev/urandom on Unix-like
 654  * systems; CryptGenRandom on Windows).  This is not actually as secure as it
 655  * should be: ARC4 is a pretty lousy cipher, and the current implementation
 656  * provides only rudimentary prediction- and backtracking-resistance.  Don't
 657  * use this for serious cryptographic applications.
 658  */
 659 void evutil_secure_rng_get_bytes(void *buf, size_t n);
 660
 661 /**
 662  * Seed the secure random number generator if needed, and return 0 on
 663  * success or -1 on failure.
 664  *
 665  * It is okay to call this function more than once; it will still return
 666  * 0 if the RNG has been successfully seeded and -1 if it can't be
 667  * seeded.
 668  *
 669  * Ordinarily you don't need to call this function from your own code;
 670  * Libevent will seed the RNG itself the first time it needs good random
 671  * numbers.  You only need to call it if (a) you want to double-check
 672  * that one of the seeding methods did succeed, or (b) you plan to drop
 673  * the capability to seed (by chrooting, or dropping capabilities, or
 674  * whatever), and you want to make sure that seeding happens before your
 675  * program loses the ability to do it.
 676  */
 677 int evutil_secure_rng_init(void);
 678
 679 /**
 680  * Set a filename to use in place of /dev/urandom for seeding the secure
 681  * PRNG. Return 0 on success, -1 on failure.
 682  *
 683  * Call this function BEFORE calling any other initialization or RNG
 684  * functions.
 685  *
 686  * (This string will _NOT_ be copied internally. Do not free it while any
 687  * user of the secure RNG might be running. Don't pass anything other than a
 688  * real /dev/...random device file here, or you might lose security.)
 689  *
 690  * This API is unstable, and might change in a future libevent version.
 691  */
 692 int evutil_secure_rng_set_urandom_device_file(char *fname);
 693
 694 /** Seed the random number generator with extra random bytes.
 695
 696     You should almost never need to call this function; it should be
 697     sufficient to invoke evutil_secure_rng_init(), or let Libevent take
 698     care of calling evutil_secure_rng_init() on its own.
 699
 700     If you call this function as a _replacement_ for the regular
 701     entropy sources, then you need to be sure that your input
 702     contains a fairly large amount of strong entropy.  Doing so is
 703     notoriously hard: most people who try get it wrong.  Watch out!
 704
 705     @param dat a buffer full of a strong source of random numbers
 706     @param datlen the number of bytes to read from datlen
 707  */
 708 void evutil_secure_rng_add_bytes(const char *dat, size_t datlen);
 709
 710 #ifdef __cplusplus
 711 }
 712 #endif
 713
 714 #endif /* _EVUTIL_H_ */