release/src/router/libevent/util-internal.h

   1 /*
   2  * Copyright (c) 2007-2010 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 _EVENT_UTIL_INTERNAL_H
  27 #define _EVENT_UTIL_INTERNAL_H
  28
  29 #include "event2/event-config.h"
  30 #include <errno.h>
  31
  32 /* For EVUTIL_ASSERT */
  33 #include "log-internal.h"
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #ifdef _EVENT_HAVE_SYS_SOCKET_H
  37 #include <sys/socket.h>
  38 #endif
  39 #include "event2/util.h"
  40
  41 #include "ipv6-internal.h"
  42
  43 #ifdef __cplusplus
  44 extern "C" {
  45 #endif
  46
  47 /* If we need magic to say "inline", get it for free internally. */
  48 #ifdef _EVENT_inline
  49 #define inline _EVENT_inline
  50 #endif
  51 #ifdef _EVENT___func__
  52 #define __func__ _EVENT___func__
  53 #endif
  54
  55 /* A good no-op to use in macro definitions. */
  56 #define _EVUTIL_NIL_STMT ((void)0)
  57 /* A no-op that tricks the compiler into thinking a condition is used while
  58  * definitely not making any code for it.  Used to compile out asserts while
  59  * avoiding "unused variable" warnings.  The "!" forces the compiler to
  60  * do the sizeof() on an int, in case "condition" is a bitfield value.
  61  */
  62 #define _EVUTIL_NIL_CONDITION(condition) do { \
  63         (void)sizeof(!(condition));  \
  64 } while(0)
  65
  66 /* Internal use only: macros to match patterns of error codes in a
  67    cross-platform way.  We need these macros because of two historical
  68    reasons: first, nonblocking IO functions are generally written to give an
  69    error on the "blocked now, try later" case, so sometimes an error from a
  70    read, write, connect, or accept means "no error; just wait for more
  71    data," and we need to look at the error code.  Second, Windows defines
  72    a different set of error codes for sockets. */
  73
  74 #ifndef WIN32
  75
  76 /* True iff e is an error that means a read/write operation can be retried. */
  77 #define EVUTIL_ERR_RW_RETRIABLE(e)                              \
  78         ((e) == EINTR || (e) == EAGAIN)
  79 /* True iff e is an error that means an connect can be retried. */
  80 #define EVUTIL_ERR_CONNECT_RETRIABLE(e)                 \
  81         ((e) == EINTR || (e) == EINPROGRESS)
  82 /* True iff e is an error that means a accept can be retried. */
  83 #define EVUTIL_ERR_ACCEPT_RETRIABLE(e)                  \
  84         ((e) == EINTR || (e) == EAGAIN || (e) == ECONNABORTED)
  85
  86 /* True iff e is an error that means the connection was refused */
  87 #define EVUTIL_ERR_CONNECT_REFUSED(e)                                   \
  88         ((e) == ECONNREFUSED)
  89
  90 #else
  91
  92 #define EVUTIL_ERR_RW_RETRIABLE(e)                                      \
  93         ((e) == WSAEWOULDBLOCK ||                                       \
  94             (e) == WSAEINTR)
  95
  96 #define EVUTIL_ERR_CONNECT_RETRIABLE(e)                                 \
  97         ((e) == WSAEWOULDBLOCK ||                                       \
  98             (e) == WSAEINTR ||                                          \
  99             (e) == WSAEINPROGRESS ||                                    \
 100             (e) == WSAEINVAL)
 101
 102 #define EVUTIL_ERR_ACCEPT_RETRIABLE(e)                  \
 103         EVUTIL_ERR_RW_RETRIABLE(e)
 104
 105 #define EVUTIL_ERR_CONNECT_REFUSED(e)                                   \
 106         ((e) == WSAECONNREFUSED)
 107
 108 #endif
 109
 110 #ifdef _EVENT_socklen_t
 111 #define socklen_t _EVENT_socklen_t
 112 #endif
 113
 114 /* Arguments for shutdown() */
 115 #ifdef SHUT_RD
 116 #define EVUTIL_SHUT_RD SHUT_RD
 117 #else
 118 #define EVUTIL_SHUT_RD 0
 119 #endif
 120 #ifdef SHUT_WR
 121 #define EVUTIL_SHUT_WR SHUT_WR
 122 #else
 123 #define EVUTIL_SHUT_WR 1
 124 #endif
 125 #ifdef SHUT_BOTH
 126 #define EVUTIL_SHUT_BOTH SHUT_BOTH
 127 #else
 128 #define EVUTIL_SHUT_BOTH 2
 129 #endif
 130
 131 /* Locale-independent replacements for some ctypes functions.  Use these
 132  * when you care about ASCII's notion of character types, because you are about
 133  * to send those types onto the wire.
 134  */
 135 int EVUTIL_ISALPHA(char c);
 136 int EVUTIL_ISALNUM(char c);
 137 int EVUTIL_ISSPACE(char c);
 138 int EVUTIL_ISDIGIT(char c);
 139 int EVUTIL_ISXDIGIT(char c);
 140 int EVUTIL_ISPRINT(char c);
 141 int EVUTIL_ISLOWER(char c);
 142 int EVUTIL_ISUPPER(char c);
 143 char EVUTIL_TOUPPER(char c);
 144 char EVUTIL_TOLOWER(char c);
 145
 146 /** Helper macro.  If we know that a given pointer points to a field in a
 147     structure, return a pointer to the structure itself.  Used to implement
 148     our half-baked C OO.  Example:
 149
 150     struct subtype {
 151         int x;
 152         struct supertype common;
 153         int y;
 154     };
 155     ...
 156     void fn(struct supertype *super) {
 157         struct subtype *sub = EVUTIL_UPCAST(super, struct subtype, common);
 158         ...
 159     }
 160  */
 161 #define EVUTIL_UPCAST(ptr, type, field)                         \
 162         ((type *)(((char*)(ptr)) - evutil_offsetof(type, field)))
 163
 164 int evutil_read_file(const char *filename, char **content_out, size_t *len_out,
 165     int is_binary);
 166
 167 int evutil_socket_connect(evutil_socket_t *fd_ptr, struct sockaddr *sa, int socklen);
 168
 169 int evutil_socket_finished_connecting(evutil_socket_t fd);
 170
 171 int evutil_ersatz_socketpair(int, int , int, evutil_socket_t[]);
 172
 173 int evutil_resolve(int family, const char *hostname, struct sockaddr *sa,
 174     ev_socklen_t *socklen, int port);
 175
 176 const char *evutil_getenv(const char *name);
 177
 178 long _evutil_weakrand(void);
 179
 180 /* Evaluates to the same boolean value as 'p', and hints to the compiler that
 181  * we expect this value to be false. */
 182 #ifdef __GNUC__
 183 #define EVUTIL_UNLIKELY(p) __builtin_expect(!!(p),0)
 184 #else
 185 #define EVUTIL_UNLIKELY(p) (p)
 186 #endif
 187
 188 /* Replacement for assert() that calls event_errx on failure. */
 189 #ifdef NDEBUG
 190 #define EVUTIL_ASSERT(cond) _EVUTIL_NIL_CONDITION(cond)
 191 #define EVUTIL_FAILURE_CHECK(cond) 0
 192 #else
 193 #define EVUTIL_ASSERT(cond)                                             \
 194         do {                                                            \
 195                 if (EVUTIL_UNLIKELY(!(cond))) {                         \
 196                         event_errx(_EVENT_ERR_ABORT,                    \
 197                             "%s:%d: Assertion %s failed in %s",         \
 198                             __FILE__,__LINE__,#cond,__func__);          \
 199                         /* In case a user-supplied handler tries to */  \
 200                         /* return control to us, log and abort here. */ \
 201                         (void)fprintf(stderr,                           \
 202                             "%s:%d: Assertion %s failed in %s",         \
 203                             __FILE__,__LINE__,#cond,__func__);          \
 204                         abort();                                        \
 205                 }                                                       \
 206         } while (0)
 207 #define EVUTIL_FAILURE_CHECK(cond) EVUTIL_UNLIKELY(cond)
 208 #endif
 209
 210 #ifndef _EVENT_HAVE_STRUCT_SOCKADDR_STORAGE
 211 /* Replacement for sockaddr storage that we can use internally on platforms
 212  * that lack it.  It is not space-efficient, but neither is sockaddr_storage.
 213  */
 214 struct sockaddr_storage {
 215         union {
 216                 struct sockaddr ss_sa;
 217                 struct sockaddr_in ss_sin;
 218                 struct sockaddr_in6 ss_sin6;
 219                 char ss_padding[128];
 220         } ss_union;
 221 };
 222 #define ss_family ss_union.ss_sa.sa_family
 223 #endif
 224
 225 /* Internal addrinfo error code.  This one is returned from only from
 226  * evutil_getaddrinfo_common, when we are sure that we'll have to hit a DNS
 227  * server. */
 228 #define EVUTIL_EAI_NEED_RESOLVE      -90002
 229
 230 struct evdns_base;
 231 struct evdns_getaddrinfo_request;
 232 typedef struct evdns_getaddrinfo_request* (*evdns_getaddrinfo_fn)(
 233     struct evdns_base *base,
 234     const char *nodename, const char *servname,
 235     const struct evutil_addrinfo *hints_in,
 236     void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
 237
 238 void evutil_set_evdns_getaddrinfo_fn(evdns_getaddrinfo_fn fn);
 239
 240 struct evutil_addrinfo *evutil_new_addrinfo(struct sockaddr *sa,
 241     ev_socklen_t socklen, const struct evutil_addrinfo *hints);
 242 struct evutil_addrinfo *evutil_addrinfo_append(struct evutil_addrinfo *first,
 243     struct evutil_addrinfo *append);
 244 void evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo *hints);
 245 int evutil_getaddrinfo_common(const char *nodename, const char *servname,
 246     struct evutil_addrinfo *hints, struct evutil_addrinfo **res, int *portnum);
 247
 248 int evutil_getaddrinfo_async(struct evdns_base *dns_base,
 249     const char *nodename, const char *servname,
 250     const struct evutil_addrinfo *hints_in,
 251     void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
 252
 253 /** Return true iff sa is a looback address. (That is, it is 127.0.0.1/8, or
 254  * ::1). */
 255 int evutil_sockaddr_is_loopback(const struct sockaddr *sa);
 256
 257
 258 /**
 259     Formats a sockaddr sa into a string buffer of size outlen stored in out.
 260     Returns a pointer to out.  Always writes something into out, so it's safe
 261     to use the output of this function without checking it for NULL.
 262  */
 263 const char *evutil_format_sockaddr_port(const struct sockaddr *sa, char *out, size_t outlen);
 264
 265 long evutil_tv_to_msec(const struct timeval *tv);
 266
 267 int evutil_hex_char_to_int(char c);
 268
 269 #ifdef WIN32
 270 HANDLE evutil_load_windows_system_library(const TCHAR *library_name);
 271 #endif
 272
 273 #ifdef __cplusplus
 274 }
 275 #endif
 276
 277 #endif