+++ /dev/null
-/*
- * Copyright (c) 2007-2010 Niels Provos and Nick Mathewson
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote products
- * derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-#ifndef _EVENT2_UTIL_H_
-#define _EVENT2_UTIL_H_
-
-/** @file event2/util.h
-
- Common convenience functions for cross-platform portability and
- related socket manipulations.
-
- */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include <event2/event-config.h>
-#ifdef _EVENT_HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
-#ifdef _EVENT_HAVE_STDINT_H
-#include <stdint.h>
-#elif defined(_EVENT_HAVE_INTTYPES_H)
-#include <inttypes.h>
-#endif
-#ifdef _EVENT_HAVE_SYS_TYPES_H
-#include <sys/types.h>
-#endif
-#ifdef _EVENT_HAVE_STDDEF_H
-#include <stddef.h>
-#endif
-#ifdef _MSC_VER
-#include <BaseTsd.h>
-#endif
-#include <stdarg.h>
-#ifdef _EVENT_HAVE_NETDB_H
-#if !defined(_GNU_SOURCE)
-#define _GNU_SOURCE
-#endif
-#include <netdb.h>
-#endif
-
-#ifdef WIN32
-#include <winsock2.h>
-#else
-#include <sys/socket.h>
-#endif
-
-/* Integer type definitions for types that are supposed to be defined in the
- * C99-specified stdint.h. Shamefully, some platforms do not include
- * stdint.h, so we need to replace it. (If you are on a platform like this,
- * your C headers are now over 10 years out of date. You should bug them to
- * do something about this.)
- *
- * We define:
- * ev_uint64_t, ev_uint32_t, ev_uint16_t, ev_uint8_t -- unsigned integer
- * types of exactly 64, 32, 16, and 8 bits respectively.
- * ev_int64_t, ev_int32_t, ev_int16_t, ev_int8_t -- signed integer
- * types of exactly 64, 32, 16, and 8 bits respectively.
- * ev_uintptr_t, ev_intptr_t -- unsigned/signed integers large enough
- * to hold a pointer without loss of bits.
- */
-#ifdef _EVENT_HAVE_UINT64_T
-#define ev_uint64_t uint64_t
-#define ev_int64_t int64_t
-#elif defined(WIN32)
-#define ev_uint64_t unsigned __int64
-#define ev_int64_t signed __int64
-#elif _EVENT_SIZEOF_LONG_LONG == 8
-#define ev_uint64_t unsigned long long
-#define ev_int64_t long long
-#elif _EVENT_SIZEOF_LONG == 8
-#define ev_uint64_t unsigned long
-#define ev_int64_t long
-#else
-#error "No way to define ev_uint64_t"
-#endif
-
-#ifdef _EVENT_HAVE_UINT32_T
-#define ev_uint32_t uint32_t
-#define ev_int32_t int32_t
-#elif defined(WIN32)
-#define ev_uint32_t unsigned int
-#define ev_int32_t signed int
-#elif _EVENT_SIZEOF_LONG == 4
-#define ev_uint32_t unsigned long
-#define ev_int32_t signed long
-#elif _EVENT_SIZEOF_INT == 4
-#define ev_uint32_t unsigned int
-#define ev_int32_t signed int
-#else
-#error "No way to define ev_uint32_t"
-#endif
-
-#ifdef _EVENT_HAVE_UINT16_T
-#define ev_uint16_t uint16_t
-#define ev_int16_t int16_t
-#elif defined(WIN32)
-#define ev_uint16_t unsigned short
-#define ev_int16_t signed short
-#elif _EVENT_SIZEOF_INT == 2
-#define ev_uint16_t unsigned int
-#define ev_int16_t signed int
-#elif _EVENT_SIZEOF_SHORT == 2
-#define ev_uint16_t unsigned short
-#define ev_int16_t signed short
-#else
-#error "No way to define ev_uint16_t"
-#endif
-
-#ifdef _EVENT_HAVE_UINT8_T
-#define ev_uint8_t uint8_t
-#define ev_int8_t int8_t
-#else
-#define ev_uint8_t unsigned char
-#define ev_int8_t signed char
-#endif
-
-/* Some openbsd autoconf versions get the name of this macro wrong. */
-#if defined(_EVENT_SIZEOF_VOID__) && !defined(_EVENT_SIZEOF_VOID_P)
-#define _EVENT_SIZEOF_VOID_P _EVENT_SIZEOF_VOID__
-#endif
-
-#ifdef _EVENT_HAVE_UINTPTR_T
-#define ev_uintptr_t uintptr_t
-#define ev_intptr_t intptr_t
-#elif _EVENT_SIZEOF_VOID_P <= 4
-#define ev_uintptr_t ev_uint32_t
-#define ev_intptr_t ev_int32_t
-#elif _EVENT_SIZEOF_VOID_P <= 8
-#define ev_uintptr_t ev_uint64_t
-#define ev_intptr_t ev_int64_t
-#else
-#error "No way to define ev_uintptr_t"
-#endif
-
-#ifdef _EVENT_ssize_t
-#define ev_ssize_t _EVENT_ssize_t
-#else
-#define ev_ssize_t ssize_t
-#endif
-
-#ifdef WIN32
-#define ev_off_t ev_int64_t
-#else
-#define ev_off_t off_t
-#endif
-
-/* Limits for integer types.
-
- We're making two assumptions here:
- - The compiler does constant folding properly.
- - The platform does signed arithmetic in two's complement.
-*/
-
-#define EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) | 0xffffffffUL)
-#define EV_INT64_MAX ((((ev_int64_t) 0x7fffffffL) << 32) | 0xffffffffL)
-#define EV_INT64_MIN ((-EV_INT64_MAX) - 1)
-#define EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL)
-#define EV_INT32_MAX ((ev_int32_t) 0x7fffffffL)
-#define EV_INT32_MIN ((-EV_INT32_MAX) - 1)
-#define EV_UINT16_MAX ((ev_uint16_t)0xffffUL)
-#define EV_INT16_MAX ((ev_int16_t) 0x7fffL)
-#define EV_INT16_MIN ((-EV_INT16_MAX) - 1)
-#define EV_UINT8_MAX 255
-#define EV_INT8_MAX 127
-#define EV_INT8_MIN ((-EV_INT8_MAX) - 1)
-
-#if _EVENT_SIZEOF_SIZE_T == 8
-#define EV_SIZE_MAX EV_UINT64_MAX
-#define EV_SSIZE_MAX EV_INT64_MAX
-#elif _EVENT_SIZEOF_SIZE_T == 4
-#define EV_SIZE_MAX EV_UINT32_MAX
-#define EV_SSIZE_MAX EV_INT32_MAX
-#else
-#error "No way to define SIZE_MAX"
-#endif
-
-#define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1)
-
-#ifdef WIN32
-#define ev_socklen_t int
-#elif defined(_EVENT_socklen_t)
-#define ev_socklen_t _EVENT_socklen_t
-#else
-#define ev_socklen_t socklen_t
-#endif
-
-#ifdef _EVENT_HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY
-#if !defined(_EVENT_HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY) \
- && !defined(ss_family)
-#define ss_family __ss_family
-#endif
-#endif
-
-#ifdef WIN32
-/** A type wide enough to hold the output of "socket()" or "accept()". On
- * Windows, this is an intptr_t; elsewhere, it is an int. */
-#define evutil_socket_t intptr_t
-#else
-#define evutil_socket_t int
-#endif
-
-/** Create two new sockets that are connected to each other. On Unix, this
- simply calls socketpair(). On Windows, it uses the loopback network
- interface on 127.0.0.1, and only AF_INET,SOCK_STREAM are supported.
-
- (This may fail on some Windows hosts where firewall software has cleverly
- decided to keep 127.0.0.1 from talking to itself.)
-
- Parameters and return values are as for socketpair()
-*/
-int evutil_socketpair(int d, int type, int protocol, evutil_socket_t sv[2]);
-/** Do platform-specific operations as needed to make a socket nonblocking.
-
- @param sock The socket to make nonblocking
- @return 0 on success, -1 on failure
- */
-int evutil_make_socket_nonblocking(evutil_socket_t sock);
-
-/** Do platform-specific operations on a listener socket to make sure that
- another program will be able to bind this address right after we've
- closed the listener
-
- @param sock The socket to make reusable
- @return 0 on success, -1 on failure
- */
-int evutil_make_listen_socket_reuseable(evutil_socket_t sock);
-
-/** Do platform-specific operations as needed to close a socket upon a
- successful execution of one of the exec*() functions.
-
- @param sock The socket to be closed
- @return 0 on success, -1 on failure
- */
-int evutil_make_socket_closeonexec(evutil_socket_t sock);
-
-/** Do the platform-specific call needed to close a socket returned from
- socket() or accept().
-
- @param sock The socket to be closed
- @return 0 on success, -1 on failure
- */
-int evutil_closesocket(evutil_socket_t sock);
-#define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s)
-
-/* Winsock handles socket errors differently from the rest of the world.
- * Elsewhere, a socket error is like any other error and is stored in errno.
- * But winsock functions require you to retrieve the error with a special
- * function, and don't let you use strerror for the error codes. And handling
- * EWOULDBLOCK is ... different. */
-
-#ifdef WIN32
-/** Return the most recent socket error. Not idempotent on all platforms. */
-#define EVUTIL_SOCKET_ERROR() WSAGetLastError()
-/** Replace the most recent socket error with errcode */
-#define EVUTIL_SET_SOCKET_ERROR(errcode) \
- do { WSASetLastError(errcode); } while (0)
-/** Return the most recent socket error to occur on sock. */
-int evutil_socket_geterror(evutil_socket_t sock);
-/** Convert a socket error to a string. */
-const char *evutil_socket_error_to_string(int errcode);
-#else
-#define EVUTIL_SOCKET_ERROR() (errno)
-#define EVUTIL_SET_SOCKET_ERROR(errcode) \
- do { errno = (errcode); } while (0)
-#define evutil_socket_geterror(sock) (errno)
-#define evutil_socket_error_to_string(errcode) (strerror(errcode))
-#endif
-
-/*
- * Manipulation macros for struct timeval. We define replacements
- * for timeradd, timersub, timerclear, timercmp, and timerisset.
- */
-#ifdef _EVENT_HAVE_TIMERADD
-#define evutil_timeradd(tvp, uvp, vvp) timeradd((tvp), (uvp), (vvp))
-#define evutil_timersub(tvp, uvp, vvp) timersub((tvp), (uvp), (vvp))
-#else
-#define evutil_timeradd(tvp, uvp, vvp) \
- do { \
- (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec; \
- (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec; \
- if ((vvp)->tv_usec >= 1000000) { \
- (vvp)->tv_sec++; \
- (vvp)->tv_usec -= 1000000; \
- } \
- } while (0)
-#define evutil_timersub(tvp, uvp, vvp) \
- do { \
- (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \
- (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \
- if ((vvp)->tv_usec < 0) { \
- (vvp)->tv_sec--; \
- (vvp)->tv_usec += 1000000; \
- } \
- } while (0)
-#endif /* !_EVENT_HAVE_HAVE_TIMERADD */
-
-#ifdef _EVENT_HAVE_TIMERCLEAR
-#define evutil_timerclear(tvp) timerclear(tvp)
-#else
-#define evutil_timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0
-#endif
-
-/** Return true iff the tvp is related to uvp according to the relational
- * operator cmp. Recognized values for cmp are ==, <=, <, >=, and >. */
-#define evutil_timercmp(tvp, uvp, cmp) \
- (((tvp)->tv_sec == (uvp)->tv_sec) ? \
- ((tvp)->tv_usec cmp (uvp)->tv_usec) : \
- ((tvp)->tv_sec cmp (uvp)->tv_sec))
-
-#ifdef _EVENT_HAVE_TIMERISSET
-#define evutil_timerisset(tvp) timerisset(tvp)
-#else
-#define evutil_timerisset(tvp) ((tvp)->tv_sec || (tvp)->tv_usec)
-#endif
-
-/* Replacement for offsetof on platforms that don't define it. */
-#ifdef offsetof
-#define evutil_offsetof(type, field) offsetof(type, field)
-#else
-#define evutil_offsetof(type, field) ((off_t)(&((type *)0)->field))
-#endif
-
-/* big-int related functions */
-/** Parse a 64-bit value from a string. Arguments are as for strtol. */
-ev_int64_t evutil_strtoll(const char *s, char **endptr, int base);
-
-/* Replacement for gettimeofday on platforms that lack it. */
-#ifdef _EVENT_HAVE_GETTIMEOFDAY
-#define evutil_gettimeofday(tv, tz) gettimeofday((tv), (tz))
-#else
-struct timezone;
-int evutil_gettimeofday(struct timeval *tv, struct timezone *tz);
-#endif
-
-/** Replacement for snprintf to get consistent behavior on platforms for
- which the return value of snprintf does not conform to C99.
- */
-int evutil_snprintf(char *buf, size_t buflen, const char *format, ...)
-#ifdef __GNUC__
- __attribute__((format(printf, 3, 4)))
-#endif
-;
-int evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap);
-
-/** Replacement for inet_ntop for platforms which lack it. */
-const char *evutil_inet_ntop(int af, const void *src, char *dst, size_t len);
-/** Replacement for inet_pton for platforms which lack it. */
-int evutil_inet_pton(int af, const char *src, void *dst);
-struct sockaddr;
-
-/** Parse an IPv4 or IPv6 address, with optional port, from a string.
-
- Recognized formats are:
- - [IPv6Address]:port
- - [IPv6Address]
- - IPv6Address
- - IPv4Address:port
- - IPv4Address
-
- If no port is specified, the port in the output is set to 0.
-
- @param str The string to parse.
- @param out A struct sockaddr to hold the result. This should probably be
- a struct sockaddr_storage.
- @param outlen A pointer to the number of bytes that that 'out' can safely
- hold. Set to the number of bytes used in 'out' on success.
- @return -1 if the address is not well-formed, if the port is out of range,
- or if out is not large enough to hold the result. Otherwise returns
- 0 on success.
-*/
-int evutil_parse_sockaddr_port(const char *str, struct sockaddr *out, int *outlen);
-
-/** Compare two sockaddrs; return 0 if they are equal, or less than 0 if sa1
- * preceeds sa2, or greater than 0 if sa1 follows sa2. If include_port is
- * true, consider the port as well as the address. Only implemented for
- * AF_INET and AF_INET6 addresses. The ordering is not guaranteed to remain
- * the same between Libevent versions. */
-int evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2,
- int include_port);
-
-/** As strcasecmp, but always compares the characters in locale-independent
- ASCII. That's useful if you're handling data in ASCII-based protocols.
- */
-int evutil_ascii_strcasecmp(const char *str1, const char *str2);
-/** As strncasecmp, but always compares the characters in locale-independent
- ASCII. That's useful if you're handling data in ASCII-based protocols.
- */
-int evutil_ascii_strncasecmp(const char *str1, const char *str2, size_t n);
-
-/* Here we define evutil_addrinfo to the native addrinfo type, or redefinte it
- * if this system has no getaddrinfo(). */
-#ifdef _EVENT_HAVE_STRUCT_ADDRINFO
-#define evutil_addrinfo addrinfo
-#else
-struct evutil_addrinfo {
- int ai_flags; /* AI_PASSIVE, AI_CANONNAME, AI_NUMERICHOST */
- int ai_family; /* PF_xxx */
- int ai_socktype; /* SOCK_xxx */
- int ai_protocol; /* 0 or IPPROTO_xxx for IPv4 and IPv6 */
- size_t ai_addrlen; /* length of ai_addr */
- char *ai_canonname; /* canonical name for nodename */
- struct sockaddr *ai_addr; /* binary address */
- struct evutil_addrinfo *ai_next; /* next structure in linked list */
-};
-#endif
-#ifdef EAI_ADDRFAMILY
-#define EVUTIL_EAI_ADDRFAMILY EAI_ADDRFAMILY
-#else
-#define EVUTIL_EAI_ADDRFAMILY -901
-#endif
-#ifdef EAI_AGAIN
-#define EVUTIL_EAI_AGAIN EAI_AGAIN
-#else
-#define EVUTIL_EAI_AGAIN -902
-#endif
-#ifdef EAI_BADFLAGS
-#define EVUTIL_EAI_BADFLAGS EAI_BADFLAGS
-#else
-#define EVUTIL_EAI_BADFLAGS -903
-#endif
-#ifdef EAI_FAIL
-#define EVUTIL_EAI_FAIL EAI_FAIL
-#else
-#define EVUTIL_EAI_FAIL -904
-#endif
-#ifdef EAI_FAMILY
-#define EVUTIL_EAI_FAMILY EAI_FAMILY
-#else
-#define EVUTIL_EAI_FAMILY -905
-#endif
-#ifdef EAI_MEMORY
-#define EVUTIL_EAI_MEMORY EAI_MEMORY
-#else
-#define EVUTIL_EAI_MEMORY -906
-#endif
-/* This test is a bit complicated, since some MS SDKs decide to
- * remove NODATA or redefine it to be the same as NONAME, in a
- * fun interpretation of RFC 2553 and RFC 3493. */
-#if defined(EAI_NODATA) && (!defined(EAI_NONAME) || EAI_NODATA != EAI_NONAME)
-#define EVUTIL_EAI_NODATA EAI_NODATA
-#else
-#define EVUTIL_EAI_NODATA -907
-#endif
-#ifdef EAI_NONAME
-#define EVUTIL_EAI_NONAME EAI_NONAME
-#else
-#define EVUTIL_EAI_NONAME -908
-#endif
-#ifdef EAI_SERVICE
-#define EVUTIL_EAI_SERVICE EAI_SERVICE
-#else
-#define EVUTIL_EAI_SERVICE -909
-#endif
-#ifdef EAI_SOCKTYPE
-#define EVUTIL_EAI_SOCKTYPE EAI_SOCKTYPE
-#else
-#define EVUTIL_EAI_SOCKTYPE -910
-#endif
-#ifdef EAI_SYSTEM
-#define EVUTIL_EAI_SYSTEM EAI_SYSTEM
-#else
-#define EVUTIL_EAI_SYSTEM -911
-#endif
-
-#define EVUTIL_EAI_CANCEL -90001
-
-#ifdef AI_PASSIVE
-#define EVUTIL_AI_PASSIVE AI_PASSIVE
-#else
-#define EVUTIL_AI_PASSIVE 0x1000
-#endif
-#ifdef AI_CANONNAME
-#define EVUTIL_AI_CANONNAME AI_CANONNAME
-#else
-#define EVUTIL_AI_CANONNAME 0x2000
-#endif
-#ifdef AI_NUMERICHOST
-#define EVUTIL_AI_NUMERICHOST AI_NUMERICHOST
-#else
-#define EVUTIL_AI_NUMERICHOST 0x4000
-#endif
-#ifdef AI_NUMERICSERV
-#define EVUTIL_AI_NUMERICSERV AI_NUMERICSERV
-#else
-#define EVUTIL_AI_NUMERICSERV 0x8000
-#endif
-#ifdef AI_V4MAPPED
-#define EVUTIL_AI_V4MAPPED AI_V4MAPPED
-#else
-#define EVUTIL_AI_V4MAPPED 0x10000
-#endif
-#ifdef AI_ALL
-#define EVUTIL_AI_ALL AI_ALL
-#else
-#define EVUTIL_AI_ALL 0x20000
-#endif
-#ifdef AI_ADDRCONFIG
-#define EVUTIL_AI_ADDRCONFIG AI_ADDRCONFIG
-#else
-#define EVUTIL_AI_ADDRCONFIG 0x40000
-#endif
-
-struct evutil_addrinfo;
-/* This function clones getaddrinfo for systems that don't have it. For full
- * details, see RFC 3493, section 6.1.
- *
- * Limitations:
- * - When the system has no getaddrinfo, we fall back to gethostbyname_r or
- * gethostbyname, with their attendant issues.
- * - The AI_V4MAPPED and AI_ALL flags are not currently implemented.
- *
- * For a nonblocking variant, see evdns_getaddrinfo.
- */
-int evutil_getaddrinfo(const char *nodename, const char *servname,
- const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res);
-
-/* Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo. */
-void evutil_freeaddrinfo(struct evutil_addrinfo *ai);
-
-const char *evutil_gai_strerror(int err);
-
-/* Generate n bytes of secure pseudorandom data, and store them in buf.
- *
- * By default, Libevent uses an ARC4-based random number generator, seeded
- * using the platform's entropy source (/dev/urandom on Unix-like systems;
- * CryptGenRandom on Windows).
- */
-void evutil_secure_rng_get_bytes(void *buf, size_t n);
-
-/**
- * Seed the secure random number generator if needed, and return 0 on
- * success or -1 on failure.
- *
- * It is okay to call this function more than once; it will still return
- * 0 if the RNG has been successfully seeded and -1 if it can't be
- * seeded.
- *
- * Ordinarily you don't need to call this function from your own code;
- * Libevent will seed the RNG itself the first time it needs good random
- * numbers. You only need to call it if (a) you want to double-check
- * that one of the seeding methods did succeed, or (b) you plan to drop
- * the capability to seed (by chrooting, or dropping capabilities, or
- * whatever), and you want to make sure that seeding happens before your
- * program loses the ability to do it.
- */
-int evutil_secure_rng_init(void);
-
-/** Seed the random number generator with extra random bytes.
-
- You should almost never need to call this function; it should be
- sufficient to invoke evutil_secure_rng_init(), or let Libevent take
- care of calling evutil_secure_rng_init() on its own.
-
- If you call this function as a _replacement_ for the regular
- entropy sources, then you need to be sure that your input
- contains a fairly large amount of strong entropy. Doing so is
- notoriously hard: most people who try get it wrong. Watch out!
-
- @param dat a buffer full of a strong source of random numbers
- @param datlen the number of bytes to read from datlen
- */
-void evutil_secure_rng_add_bytes(const char *dat, size_t datlen);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _EVUTIL_H_ */
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