1 /* 2 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 #ifndef EVENT2_UTIL_H_INCLUDED_ 27 #define EVENT2_UTIL_H_INCLUDED_ 28 29 /** @file event2/util.h 30 31 Common convenience functions for cross-platform portability and 32 related socket manipulations. 33 34 */ 35 #include <event2/visibility.h> 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 #ifdef EVENT__HAVE_GETADDRINFO 70 /* for EAI_* definitions. */ 71 #include <ws2tcpip.h> 72 #endif 73 #else 74 #include <sys/socket.h> 75 #endif 76 77 /* Some openbsd autoconf versions get the name of this macro wrong. */ 78 #if defined(EVENT__SIZEOF_VOID__) && !defined(EVENT__SIZEOF_VOID_P) 79 #define EVENT__SIZEOF_VOID_P EVENT__SIZEOF_VOID__ 80 #endif 81 82 /** 83 * @name Standard integer types. 84 * 85 * Integer type definitions for types that are supposed to be defined in the 86 * C99-specified stdint.h. Shamefully, some platforms do not include 87 * stdint.h, so we need to replace it. (If you are on a platform like this, 88 * your C headers are now over 10 years out of date. You should bug them to 89 * do something about this.) 90 * 91 * We define: 92 * 93 * <dl> 94 * <dt>ev_uint64_t, ev_uint32_t, ev_uint16_t, ev_uint8_t</dt> 95 * <dd>unsigned integer types of exactly 64, 32, 16, and 8 bits 96 * respectively.</dd> 97 * <dt>ev_int64_t, ev_int32_t, ev_int16_t, ev_int8_t</dt> 98 * <dd>signed integer types of exactly 64, 32, 16, and 8 bits 99 * respectively.</dd> 100 * <dt>ev_uintptr_t, ev_intptr_t</dt> 101 * <dd>unsigned/signed integers large enough 102 * to hold a pointer without loss of bits.</dd> 103 * <dt>ev_ssize_t</dt> 104 * <dd>A signed type of the same size as size_t</dd> 105 * <dt>ev_off_t</dt> 106 * <dd>A signed type typically used to represent offsets within a 107 * (potentially large) file</dd> 108 * 109 * @{ 110 */ 111 #ifdef EVENT__HAVE_UINT64_T 112 #define ev_uint64_t uint64_t 113 #define ev_int64_t int64_t 114 #elif defined(_WIN32) 115 #define ev_uint64_t unsigned __int64 116 #define ev_int64_t signed __int64 117 #elif EVENT__SIZEOF_LONG_LONG == 8 118 #define ev_uint64_t unsigned long long 119 #define ev_int64_t long long 120 #elif EVENT__SIZEOF_LONG == 8 121 #define ev_uint64_t unsigned long 122 #define ev_int64_t long 123 #elif defined(EVENT_IN_DOXYGEN_) 124 #define ev_uint64_t ... 125 #define ev_int64_t ... 126 #else 127 #error "No way to define ev_uint64_t" 128 #endif 129 130 #ifdef EVENT__HAVE_UINT32_T 131 #define ev_uint32_t uint32_t 132 #define ev_int32_t int32_t 133 #elif defined(_WIN32) 134 #define ev_uint32_t unsigned int 135 #define ev_int32_t signed int 136 #elif EVENT__SIZEOF_LONG == 4 137 #define ev_uint32_t unsigned long 138 #define ev_int32_t signed long 139 #elif EVENT__SIZEOF_INT == 4 140 #define ev_uint32_t unsigned int 141 #define ev_int32_t signed int 142 #elif defined(EVENT_IN_DOXYGEN_) 143 #define ev_uint32_t ... 144 #define ev_int32_t ... 145 #else 146 #error "No way to define ev_uint32_t" 147 #endif 148 149 #ifdef EVENT__HAVE_UINT16_T 150 #define ev_uint16_t uint16_t 151 #define ev_int16_t int16_t 152 #elif defined(_WIN32) 153 #define ev_uint16_t unsigned short 154 #define ev_int16_t signed short 155 #elif EVENT__SIZEOF_INT == 2 156 #define ev_uint16_t unsigned int 157 #define ev_int16_t signed int 158 #elif EVENT__SIZEOF_SHORT == 2 159 #define ev_uint16_t unsigned short 160 #define ev_int16_t signed short 161 #elif defined(EVENT_IN_DOXYGEN_) 162 #define ev_uint16_t ... 163 #define ev_int16_t ... 164 #else 165 #error "No way to define ev_uint16_t" 166 #endif 167 168 #ifdef EVENT__HAVE_UINT8_T 169 #define ev_uint8_t uint8_t 170 #define ev_int8_t int8_t 171 #elif defined(EVENT_IN_DOXYGEN_) 172 #define ev_uint8_t ... 173 #define ev_int8_t ... 174 #else 175 #define ev_uint8_t unsigned char 176 #define ev_int8_t signed char 177 #endif 178 179 #ifdef EVENT__HAVE_UINTPTR_T 180 #define ev_uintptr_t uintptr_t 181 #define ev_intptr_t intptr_t 182 #elif EVENT__SIZEOF_VOID_P <= 4 183 #define ev_uintptr_t ev_uint32_t 184 #define ev_intptr_t ev_int32_t 185 #elif EVENT__SIZEOF_VOID_P <= 8 186 #define ev_uintptr_t ev_uint64_t 187 #define ev_intptr_t ev_int64_t 188 #elif defined(EVENT_IN_DOXYGEN_) 189 #define ev_uintptr_t ... 190 #define ev_intptr_t ... 191 #else 192 #error "No way to define ev_uintptr_t" 193 #endif 194 195 #ifdef EVENT__ssize_t 196 #define ev_ssize_t EVENT__ssize_t 197 #else 198 #define ev_ssize_t ssize_t 199 #endif 200 201 /* Note that we define ev_off_t based on the compile-time size of off_t that 202 * we used to build Libevent, and not based on the current size of off_t. 203 * (For example, we don't define ev_off_t to off_t.). We do this because 204 * some systems let you build your software with different off_t sizes 205 * at runtime, and so putting in any dependency on off_t would risk API 206 * mismatch. 207 */ 208 #ifdef _WIN32 209 #define ev_off_t ev_int64_t 210 #elif EVENT__SIZEOF_OFF_T == 8 211 #define ev_off_t ev_int64_t 212 #elif EVENT__SIZEOF_OFF_T == 4 213 #define ev_off_t ev_int32_t 214 #elif defined(EVENT_IN_DOXYGEN_) 215 #define ev_off_t ... 216 #else 217 #define ev_off_t off_t 218 #endif 219 /**@}*/ 220 221 /* Limits for integer types. 222 223 We're making two assumptions here: 224 - The compiler does constant folding properly. 225 - The platform does signed arithmetic in two's complement. 226 */ 227 228 /** 229 @name Limits for integer types 230 231 These macros hold the largest or smallest values possible for the 232 ev_[u]int*_t types. 233 234 @{ 235 */ 236 #ifndef EVENT__HAVE_STDINT_H 237 #define EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) | 0xffffffffUL) 238 #define EV_INT64_MAX ((((ev_int64_t) 0x7fffffffL) << 32) | 0xffffffffL) 239 #define EV_INT64_MIN ((-EV_INT64_MAX) - 1) 240 #define EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL) 241 #define EV_INT32_MAX ((ev_int32_t) 0x7fffffffL) 242 #define EV_INT32_MIN ((-EV_INT32_MAX) - 1) 243 #define EV_UINT16_MAX ((ev_uint16_t)0xffffUL) 244 #define EV_INT16_MAX ((ev_int16_t) 0x7fffL) 245 #define EV_INT16_MIN ((-EV_INT16_MAX) - 1) 246 #define EV_UINT8_MAX 255 247 #define EV_INT8_MAX 127 248 #define EV_INT8_MIN ((-EV_INT8_MAX) - 1) 249 #else 250 #define EV_UINT64_MAX UINT64_MAX 251 #define EV_INT64_MAX INT64_MAX 252 #define EV_INT64_MIN INT64_MIN 253 #define EV_UINT32_MAX UINT32_MAX 254 #define EV_INT32_MAX INT32_MAX 255 #define EV_INT32_MIN INT32_MIN 256 #define EV_UINT16_MAX UINT16_MAX 257 #define EV_INT16_MAX INT16_MAX 258 #define EV_UINT8_MAX UINT8_MAX 259 #define EV_INT8_MAX INT8_MAX 260 #define EV_INT8_MIN INT8_MIN 261 /** @} */ 262 #endif 263 264 265 /** 266 @name Limits for SIZE_T and SSIZE_T 267 268 @{ 269 */ 270 #if EVENT__SIZEOF_SIZE_T == 8 271 #define EV_SIZE_MAX EV_UINT64_MAX 272 #define EV_SSIZE_MAX EV_INT64_MAX 273 #elif EVENT__SIZEOF_SIZE_T == 4 274 #define EV_SIZE_MAX EV_UINT32_MAX 275 #define EV_SSIZE_MAX EV_INT32_MAX 276 #elif defined(EVENT_IN_DOXYGEN_) 277 #define EV_SIZE_MAX ... 278 #define EV_SSIZE_MAX ... 279 #else 280 #error "No way to define SIZE_MAX" 281 #endif 282 283 #define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1) 284 /**@}*/ 285 286 #ifdef _WIN32 287 #define ev_socklen_t int 288 #elif defined(EVENT__socklen_t) 289 #define ev_socklen_t EVENT__socklen_t 290 #else 291 #define ev_socklen_t socklen_t 292 #endif 293 294 #ifdef EVENT__HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY 295 #if !defined(EVENT__HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY) \ 296 && !defined(ss_family) 297 #define ss_family __ss_family 298 #endif 299 #endif 300 301 /** 302 * A type wide enough to hold the output of "socket()" or "accept()". On 303 * Windows, this is an SOCKET; elsewhere, it is an int. */ 304 #ifdef _WIN32 305 #define evutil_socket_t SOCKET 306 #else 307 #define evutil_socket_t int 308 #endif 309 310 /** 311 * Structure to hold information about a monotonic timer 312 * 313 * Use this with evutil_configure_monotonic_time() and 314 * evutil_gettime_monotonic(). 315 * 316 * This is an opaque structure; you can allocate one using 317 * evutil_monotonic_timer_new(). 318 * 319 * @see evutil_monotonic_timer_new(), evutil_monotonic_timer_free(), 320 * evutil_configure_monotonic_time(), evutil_gettime_monotonic() 321 */ 322 struct evutil_monotonic_timer 323 #ifdef EVENT_IN_DOXYGEN_ 324 {/*Empty body so that doxygen will generate documentation here.*/} 325 #endif 326 ; 327 328 #define EV_MONOT_PRECISE 1 329 #define EV_MONOT_FALLBACK 2 330 331 /** Allocate a new struct evutil_monotonic_timer for use with the 332 * evutil_configure_monotonic_time() and evutil_gettime_monotonic() 333 * functions. You must configure the timer with 334 * evutil_configure_monotonic_time() before using it. 335 */ 336 EVENT2_EXPORT_SYMBOL 337 struct evutil_monotonic_timer * evutil_monotonic_timer_new(void); 338 339 /** Free a struct evutil_monotonic_timer that was allocated using 340 * evutil_monotonic_timer_new(). 341 */ 342 EVENT2_EXPORT_SYMBOL 343 void evutil_monotonic_timer_free(struct evutil_monotonic_timer *timer); 344 345 /** Set up a struct evutil_monotonic_timer; flags can include 346 * EV_MONOT_PRECISE and EV_MONOT_FALLBACK. 347 */ 348 EVENT2_EXPORT_SYMBOL 349 int evutil_configure_monotonic_time(struct evutil_monotonic_timer *timer, 350 int flags); 351 352 /** Query the current monotonic time from a struct evutil_monotonic_timer 353 * previously configured with evutil_configure_monotonic_time(). Monotonic 354 * time is guaranteed never to run in reverse, but is not necessarily epoch- 355 * based, or relative to any other definite point. Use it to make reliable 356 * measurements of elapsed time between events even when the system time 357 * may be changed. 358 * 359 * It is not safe to use this funtion on the same timer from multiple 360 * threads. 361 */ 362 EVENT2_EXPORT_SYMBOL 363 int evutil_gettime_monotonic(struct evutil_monotonic_timer *timer, 364 struct timeval *tp); 365 366 /** Create two new sockets that are connected to each other. 367 368 On Unix, this simply calls socketpair(). On Windows, it uses the 369 loopback network interface on 127.0.0.1, and only 370 AF_INET,SOCK_STREAM are supported. 371 372 (This may fail on some Windows hosts where firewall software has cleverly 373 decided to keep 127.0.0.1 from talking to itself.) 374 375 Parameters and return values are as for socketpair() 376 */ 377 EVENT2_EXPORT_SYMBOL 378 int evutil_socketpair(int d, int type, int protocol, evutil_socket_t sv[2]); 379 /** Do platform-specific operations as needed to make a socket nonblocking. 380 381 @param sock The socket to make nonblocking 382 @return 0 on success, -1 on failure 383 */ 384 EVENT2_EXPORT_SYMBOL 385 int evutil_make_socket_nonblocking(evutil_socket_t sock); 386 387 /** Do platform-specific operations to make a listener socket reusable. 388 389 Specifically, we want to make sure that another program will be able 390 to bind this address right after we've closed the listener. 391 392 This differs from Windows's interpretation of "reusable", which 393 allows multiple listeners to bind the same address at the same time. 394 395 @param sock The socket to make reusable 396 @return 0 on success, -1 on failure 397 */ 398 EVENT2_EXPORT_SYMBOL 399 int evutil_make_listen_socket_reuseable(evutil_socket_t sock); 400 401 /** Do platform-specific operations to make a listener port reusable. 402 403 Specifically, we want to make sure that multiple programs which also 404 set the same socket option will be able to bind, listen at the same time. 405 406 This is a feature available only to Linux 3.9+ 407 408 @param sock The socket to make reusable 409 @return 0 on success, -1 on failure 410 */ 411 EVENT2_EXPORT_SYMBOL 412 int evutil_make_listen_socket_reuseable_port(evutil_socket_t sock); 413 414 /** Do platform-specific operations as needed to close a socket upon a 415 successful execution of one of the exec*() functions. 416 417 @param sock The socket to be closed 418 @return 0 on success, -1 on failure 419 */ 420 EVENT2_EXPORT_SYMBOL 421 int evutil_make_socket_closeonexec(evutil_socket_t sock); 422 423 /** Do the platform-specific call needed to close a socket returned from 424 socket() or accept(). 425 426 @param sock The socket to be closed 427 @return 0 on success, -1 on failure 428 */ 429 EVENT2_EXPORT_SYMBOL 430 int evutil_closesocket(evutil_socket_t sock); 431 #define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s) 432 433 /** Do platform-specific operations, if possible, to make a tcp listener 434 * socket defer accept()s until there is data to read. 435 * 436 * Not all platforms support this. You don't want to do this for every 437 * listener socket: only the ones that implement a protocol where the 438 * client transmits before the server needs to respond. 439 * 440 * @param sock The listening socket to to make deferred 441 * @return 0 on success (whether the operation is supported or not), 442 * -1 on failure 443 */ 444 EVENT2_EXPORT_SYMBOL 445 int evutil_make_tcp_listen_socket_deferred(evutil_socket_t sock); 446 447 #ifdef _WIN32 448 /** Return the most recent socket error. Not idempotent on all platforms. */ 449 #define EVUTIL_SOCKET_ERROR() WSAGetLastError() 450 /** Replace the most recent socket error with errcode */ 451 #define EVUTIL_SET_SOCKET_ERROR(errcode) \ 452 do { WSASetLastError(errcode); } while (0) 453 /** Return the most recent socket error to occur on sock. */ 454 EVENT2_EXPORT_SYMBOL 455 int evutil_socket_geterror(evutil_socket_t sock); 456 /** Convert a socket error to a string. */ 457 EVENT2_EXPORT_SYMBOL 458 const char *evutil_socket_error_to_string(int errcode); 459 #elif defined(EVENT_IN_DOXYGEN_) 460 /** 461 @name Socket error functions 462 463 These functions are needed for making programs compatible between 464 Windows and Unix-like platforms. 465 466 You see, Winsock handles socket errors differently from the rest of 467 the world. Elsewhere, a socket error is like any other error and is 468 stored in errno. But winsock functions require you to retrieve the 469 error with a special function, and don't let you use strerror for 470 the error codes. And handling EWOULDBLOCK is ... different. 471 472 @{ 473 */ 474 /** Return the most recent socket error. Not idempotent on all platforms. */ 475 #define EVUTIL_SOCKET_ERROR() ... 476 /** Replace the most recent socket error with errcode */ 477 #define EVUTIL_SET_SOCKET_ERROR(errcode) ... 478 /** Return the most recent socket error to occur on sock. */ 479 #define evutil_socket_geterror(sock) ... 480 /** Convert a socket error to a string. */ 481 #define evutil_socket_error_to_string(errcode) ... 482 /**@}*/ 483 #else 484 #define EVUTIL_SOCKET_ERROR() (errno) 485 #define EVUTIL_SET_SOCKET_ERROR(errcode) \ 486 do { errno = (errcode); } while (0) 487 #define evutil_socket_geterror(sock) (errno) 488 #define evutil_socket_error_to_string(errcode) (strerror(errcode)) 489 #endif 490 491 492 /** 493 * @name Manipulation macros for struct timeval. 494 * 495 * We define replacements 496 * for timeradd, timersub, timerclear, timercmp, and timerisset. 497 * 498 * @{ 499 */ 500 #ifdef EVENT__HAVE_TIMERADD 501 #define evutil_timeradd(tvp, uvp, vvp) timeradd((tvp), (uvp), (vvp)) 502 #define evutil_timersub(tvp, uvp, vvp) timersub((tvp), (uvp), (vvp)) 503 #else 504 #define evutil_timeradd(tvp, uvp, vvp) \ 505 do { \ 506 (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec; \ 507 (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec; \ 508 if ((vvp)->tv_usec >= 1000000) { \ 509 (vvp)->tv_sec++; \ 510 (vvp)->tv_usec -= 1000000; \ 511 } \ 512 } while (0) 513 #define evutil_timersub(tvp, uvp, vvp) \ 514 do { \ 515 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 516 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 517 if ((vvp)->tv_usec < 0) { \ 518 (vvp)->tv_sec--; \ 519 (vvp)->tv_usec += 1000000; \ 520 } \ 521 } while (0) 522 #endif /* !EVENT__HAVE_TIMERADD */ 523 524 #ifdef EVENT__HAVE_TIMERCLEAR 525 #define evutil_timerclear(tvp) timerclear(tvp) 526 #else 527 #define evutil_timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0 528 #endif 529 /**@}*/ 530 531 /** Return true iff the tvp is related to uvp according to the relational 532 * operator cmp. Recognized values for cmp are ==, <=, <, >=, and >. */ 533 #define evutil_timercmp(tvp, uvp, cmp) \ 534 (((tvp)->tv_sec == (uvp)->tv_sec) ? \ 535 ((tvp)->tv_usec cmp (uvp)->tv_usec) : \ 536 ((tvp)->tv_sec cmp (uvp)->tv_sec)) 537 538 #ifdef EVENT__HAVE_TIMERISSET 539 #define evutil_timerisset(tvp) timerisset(tvp) 540 #else 541 #define evutil_timerisset(tvp) ((tvp)->tv_sec || (tvp)->tv_usec) 542 #endif 543 544 /** Replacement for offsetof on platforms that don't define it. */ 545 #ifdef offsetof 546 #define evutil_offsetof(type, field) offsetof(type, field) 547 #else 548 #define evutil_offsetof(type, field) ((off_t)(&((type *)0)->field)) 549 #endif 550 551 /* big-int related functions */ 552 /** Parse a 64-bit value from a string. Arguments are as for strtol. */ 553 EVENT2_EXPORT_SYMBOL 554 ev_int64_t evutil_strtoll(const char *s, char **endptr, int base); 555 556 /** Replacement for gettimeofday on platforms that lack it. */ 557 #ifdef EVENT__HAVE_GETTIMEOFDAY 558 #define evutil_gettimeofday(tv, tz) gettimeofday((tv), (tz)) 559 #else 560 struct timezone; 561 EVENT2_EXPORT_SYMBOL 562 int evutil_gettimeofday(struct timeval *tv, struct timezone *tz); 563 #endif 564 565 /** Replacement for snprintf to get consistent behavior on platforms for 566 which the return value of snprintf does not conform to C99. 567 */ 568 EVENT2_EXPORT_SYMBOL 569 int evutil_snprintf(char *buf, size_t buflen, const char *format, ...) 570 #ifdef __GNUC__ 571 __attribute__((format(printf, 3, 4))) 572 #endif 573 ; 574 /** Replacement for vsnprintf to get consistent behavior on platforms for 575 which the return value of snprintf does not conform to C99. 576 */ 577 EVENT2_EXPORT_SYMBOL 578 int evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap) 579 #ifdef __GNUC__ 580 __attribute__((format(printf, 3, 0))) 581 #endif 582 ; 583 584 /** Replacement for inet_ntop for platforms which lack it. */ 585 EVENT2_EXPORT_SYMBOL 586 const char *evutil_inet_ntop(int af, const void *src, char *dst, size_t len); 587 /** Replacement for inet_pton for platforms which lack it. */ 588 EVENT2_EXPORT_SYMBOL 589 int evutil_inet_pton(int af, const char *src, void *dst); 590 struct sockaddr; 591 592 /** Parse an IPv4 or IPv6 address, with optional port, from a string. 593 594 Recognized formats are: 595 - [IPv6Address]:port 596 - [IPv6Address] 597 - IPv6Address 598 - IPv4Address:port 599 - IPv4Address 600 601 If no port is specified, the port in the output is set to 0. 602 603 @param str The string to parse. 604 @param out A struct sockaddr to hold the result. This should probably be 605 a struct sockaddr_storage. 606 @param outlen A pointer to the number of bytes that that 'out' can safely 607 hold. Set to the number of bytes used in 'out' on success. 608 @return -1 if the address is not well-formed, if the port is out of range, 609 or if out is not large enough to hold the result. Otherwise returns 610 0 on success. 611 */ 612 EVENT2_EXPORT_SYMBOL 613 int evutil_parse_sockaddr_port(const char *str, struct sockaddr *out, int *outlen); 614 615 /** Compare two sockaddrs; return 0 if they are equal, or less than 0 if sa1 616 * preceeds sa2, or greater than 0 if sa1 follows sa2. If include_port is 617 * true, consider the port as well as the address. Only implemented for 618 * AF_INET and AF_INET6 addresses. The ordering is not guaranteed to remain 619 * the same between Libevent versions. */ 620 EVENT2_EXPORT_SYMBOL 621 int evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2, 622 int include_port); 623 624 /** As strcasecmp, but always compares the characters in locale-independent 625 ASCII. That's useful if you're handling data in ASCII-based protocols. 626 */ 627 EVENT2_EXPORT_SYMBOL 628 int evutil_ascii_strcasecmp(const char *str1, const char *str2); 629 /** As strncasecmp, but always compares the characters in locale-independent 630 ASCII. That's useful if you're handling data in ASCII-based protocols. 631 */ 632 EVENT2_EXPORT_SYMBOL 633 int evutil_ascii_strncasecmp(const char *str1, const char *str2, size_t n); 634 635 /* Here we define evutil_addrinfo to the native addrinfo type, or redefine it 636 * if this system has no getaddrinfo(). */ 637 #ifdef EVENT__HAVE_STRUCT_ADDRINFO 638 #define evutil_addrinfo addrinfo 639 #else 640 /** A definition of struct addrinfo for systems that lack it. 641 642 (This is just an alias for struct addrinfo if the system defines 643 struct addrinfo.) 644 */ 645 struct evutil_addrinfo { 646 int ai_flags; /* AI_PASSIVE, AI_CANONNAME, AI_NUMERICHOST */ 647 int ai_family; /* PF_xxx */ 648 int ai_socktype; /* SOCK_xxx */ 649 int ai_protocol; /* 0 or IPPROTO_xxx for IPv4 and IPv6 */ 650 size_t ai_addrlen; /* length of ai_addr */ 651 char *ai_canonname; /* canonical name for nodename */ 652 struct sockaddr *ai_addr; /* binary address */ 653 struct evutil_addrinfo *ai_next; /* next structure in linked list */ 654 }; 655 #endif 656 /** @name evutil_getaddrinfo() error codes 657 658 These values are possible error codes for evutil_getaddrinfo() and 659 related functions. 660 661 @{ 662 */ 663 #if defined(EAI_ADDRFAMILY) && defined(EVENT__HAVE_GETADDRINFO) 664 #define EVUTIL_EAI_ADDRFAMILY EAI_ADDRFAMILY 665 #else 666 #define EVUTIL_EAI_ADDRFAMILY -901 667 #endif 668 #if defined(EAI_AGAIN) && defined(EVENT__HAVE_GETADDRINFO) 669 #define EVUTIL_EAI_AGAIN EAI_AGAIN 670 #else 671 #define EVUTIL_EAI_AGAIN -902 672 #endif 673 #if defined(EAI_BADFLAGS) && defined(EVENT__HAVE_GETADDRINFO) 674 #define EVUTIL_EAI_BADFLAGS EAI_BADFLAGS 675 #else 676 #define EVUTIL_EAI_BADFLAGS -903 677 #endif 678 #if defined(EAI_FAIL) && defined(EVENT__HAVE_GETADDRINFO) 679 #define EVUTIL_EAI_FAIL EAI_FAIL 680 #else 681 #define EVUTIL_EAI_FAIL -904 682 #endif 683 #if defined(EAI_FAMILY) && defined(EVENT__HAVE_GETADDRINFO) 684 #define EVUTIL_EAI_FAMILY EAI_FAMILY 685 #else 686 #define EVUTIL_EAI_FAMILY -905 687 #endif 688 #if defined(EAI_MEMORY) && defined(EVENT__HAVE_GETADDRINFO) 689 #define EVUTIL_EAI_MEMORY EAI_MEMORY 690 #else 691 #define EVUTIL_EAI_MEMORY -906 692 #endif 693 /* This test is a bit complicated, since some MS SDKs decide to 694 * remove NODATA or redefine it to be the same as NONAME, in a 695 * fun interpretation of RFC 2553 and RFC 3493. */ 696 #if defined(EAI_NODATA) && defined(EVENT__HAVE_GETADDRINFO) && (!defined(EAI_NONAME) || EAI_NODATA != EAI_NONAME) 697 #define EVUTIL_EAI_NODATA EAI_NODATA 698 #else 699 #define EVUTIL_EAI_NODATA -907 700 #endif 701 #if defined(EAI_NONAME) && defined(EVENT__HAVE_GETADDRINFO) 702 #define EVUTIL_EAI_NONAME EAI_NONAME 703 #else 704 #define EVUTIL_EAI_NONAME -908 705 #endif 706 #if defined(EAI_SERVICE) && defined(EVENT__HAVE_GETADDRINFO) 707 #define EVUTIL_EAI_SERVICE EAI_SERVICE 708 #else 709 #define EVUTIL_EAI_SERVICE -909 710 #endif 711 #if defined(EAI_SOCKTYPE) && defined(EVENT__HAVE_GETADDRINFO) 712 #define EVUTIL_EAI_SOCKTYPE EAI_SOCKTYPE 713 #else 714 #define EVUTIL_EAI_SOCKTYPE -910 715 #endif 716 #if defined(EAI_SYSTEM) && defined(EVENT__HAVE_GETADDRINFO) 717 #define EVUTIL_EAI_SYSTEM EAI_SYSTEM 718 #else 719 #define EVUTIL_EAI_SYSTEM -911 720 #endif 721 722 #define EVUTIL_EAI_CANCEL -90001 723 724 #if defined(AI_PASSIVE) && defined(EVENT__HAVE_GETADDRINFO) 725 #define EVUTIL_AI_PASSIVE AI_PASSIVE 726 #else 727 #define EVUTIL_AI_PASSIVE 0x1000 728 #endif 729 #if defined(AI_CANONNAME) && defined(EVENT__HAVE_GETADDRINFO) 730 #define EVUTIL_AI_CANONNAME AI_CANONNAME 731 #else 732 #define EVUTIL_AI_CANONNAME 0x2000 733 #endif 734 #if defined(AI_NUMERICHOST) && defined(EVENT__HAVE_GETADDRINFO) 735 #define EVUTIL_AI_NUMERICHOST AI_NUMERICHOST 736 #else 737 #define EVUTIL_AI_NUMERICHOST 0x4000 738 #endif 739 #if defined(AI_NUMERICSERV) && defined(EVENT__HAVE_GETADDRINFO) 740 #define EVUTIL_AI_NUMERICSERV AI_NUMERICSERV 741 #else 742 #define EVUTIL_AI_NUMERICSERV 0x8000 743 #endif 744 #if defined(AI_V4MAPPED) && defined(EVENT__HAVE_GETADDRINFO) 745 #define EVUTIL_AI_V4MAPPED AI_V4MAPPED 746 #else 747 #define EVUTIL_AI_V4MAPPED 0x10000 748 #endif 749 #if defined(AI_ALL) && defined(EVENT__HAVE_GETADDRINFO) 750 #define EVUTIL_AI_ALL AI_ALL 751 #else 752 #define EVUTIL_AI_ALL 0x20000 753 #endif 754 #if defined(AI_ADDRCONFIG) && defined(EVENT__HAVE_GETADDRINFO) 755 #define EVUTIL_AI_ADDRCONFIG AI_ADDRCONFIG 756 #else 757 #define EVUTIL_AI_ADDRCONFIG 0x40000 758 #endif 759 /**@}*/ 760 761 struct evutil_addrinfo; 762 /** 763 * This function clones getaddrinfo for systems that don't have it. For full 764 * details, see RFC 3493, section 6.1. 765 * 766 * Limitations: 767 * - When the system has no getaddrinfo, we fall back to gethostbyname_r or 768 * gethostbyname, with their attendant issues. 769 * - The AI_V4MAPPED and AI_ALL flags are not currently implemented. 770 * 771 * For a nonblocking variant, see evdns_getaddrinfo. 772 */ 773 EVENT2_EXPORT_SYMBOL 774 int evutil_getaddrinfo(const char *nodename, const char *servname, 775 const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res); 776 777 /** Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo. */ 778 EVENT2_EXPORT_SYMBOL 779 void evutil_freeaddrinfo(struct evutil_addrinfo *ai); 780 781 EVENT2_EXPORT_SYMBOL 782 const char *evutil_gai_strerror(int err); 783 784 /** Generate n bytes of secure pseudorandom data, and store them in buf. 785 * 786 * Current versions of Libevent use an ARC4-based random number generator, 787 * seeded using the platform's entropy source (/dev/urandom on Unix-like 788 * systems; CryptGenRandom on Windows). This is not actually as secure as it 789 * should be: ARC4 is a pretty lousy cipher, and the current implementation 790 * provides only rudimentary prediction- and backtracking-resistance. Don't 791 * use this for serious cryptographic applications. 792 */ 793 EVENT2_EXPORT_SYMBOL 794 void evutil_secure_rng_get_bytes(void *buf, size_t n); 795 796 /** 797 * Seed the secure random number generator if needed, and return 0 on 798 * success or -1 on failure. 799 * 800 * It is okay to call this function more than once; it will still return 801 * 0 if the RNG has been successfully seeded and -1 if it can't be 802 * seeded. 803 * 804 * Ordinarily you don't need to call this function from your own code; 805 * Libevent will seed the RNG itself the first time it needs good random 806 * numbers. You only need to call it if (a) you want to double-check 807 * that one of the seeding methods did succeed, or (b) you plan to drop 808 * the capability to seed (by chrooting, or dropping capabilities, or 809 * whatever), and you want to make sure that seeding happens before your 810 * program loses the ability to do it. 811 */ 812 EVENT2_EXPORT_SYMBOL 813 int evutil_secure_rng_init(void); 814 815 /** 816 * Set a filename to use in place of /dev/urandom for seeding the secure 817 * PRNG. Return 0 on success, -1 on failure. 818 * 819 * Call this function BEFORE calling any other initialization or RNG 820 * functions. 821 * 822 * (This string will _NOT_ be copied internally. Do not free it while any 823 * user of the secure RNG might be running. Don't pass anything other than a 824 * real /dev/...random device file here, or you might lose security.) 825 * 826 * This API is unstable, and might change in a future libevent version. 827 */ 828 EVENT2_EXPORT_SYMBOL 829 int evutil_secure_rng_set_urandom_device_file(char *fname); 830 831 /** Seed the random number generator with extra random bytes. 832 833 You should almost never need to call this function; it should be 834 sufficient to invoke evutil_secure_rng_init(), or let Libevent take 835 care of calling evutil_secure_rng_init() on its own. 836 837 If you call this function as a _replacement_ for the regular 838 entropy sources, then you need to be sure that your input 839 contains a fairly large amount of strong entropy. Doing so is 840 notoriously hard: most people who try get it wrong. Watch out! 841 842 @param dat a buffer full of a strong source of random numbers 843 @param datlen the number of bytes to read from datlen 844 */ 845 EVENT2_EXPORT_SYMBOL 846 void evutil_secure_rng_add_bytes(const char *dat, size_t datlen); 847 848 #ifdef __cplusplus 849 } 850 #endif 851 852 #endif /* EVENT1_EVUTIL_H_INCLUDED_ */ 853