path: root/contrib/libs/libevent/util-internal.h

/*
 * Copyright (c) 2007-2012 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 UTIL_INTERNAL_H_INCLUDED_ 
#define UTIL_INTERNAL_H_INCLUDED_ 

#include "event2/event-config.h"
#include "evconfig-private.h" 
 
#include <errno.h>

/* For EVUTIL_ASSERT */
#include "log-internal.h"
#include <stdio.h>
#include <stdlib.h>
#ifdef EVENT__HAVE_SYS_SOCKET_H 
#include <sys/socket.h>
#endif
#ifdef EVENT__HAVE_SYS_EVENTFD_H 
#include <sys/eventfd.h> 
#endif 
#include "event2/util.h"

#include "time-internal.h" 
#include "ipv6-internal.h"

#ifdef __cplusplus
extern "C" {
#endif

/* __has_attribute() wrapper */ 
#ifdef __has_attribute 
# define EVUTIL_HAS_ATTRIBUTE __has_attribute 
#endif 
/** clang 3 __has_attribute misbehaves in some versions */ 
#if defined(__clang__) && __clang__ == 1 
# if defined(__apple_build_version__) 
#  if __clang_major__ <= 6 
#   undef EVUTIL_HAS_ATTRIBUTE 
#  endif 
# else /* !__apple_build_version__ */ 
#  if __clang_major__ == 3 && __clang_minor__ >= 2 && __clang_minor__ <= 5 
#   undef EVUTIL_HAS_ATTRIBUTE 
#  endif 
# endif /* __apple_build_version__ */ 
#endif /*\ defined(__clang__) && __clang__ == 1 */ 
#ifndef EVUTIL_HAS_ATTRIBUTE 
# define EVUTIL_HAS_ATTRIBUTE(x) 0 
#endif 
 
/* If we need magic to say "inline", get it for free internally. */
#ifdef EVENT__inline 
#define inline EVENT__inline 
#endif
 
/* Define to appropriate substitute if compiler doesnt have __func__ */ 
#if defined(EVENT__HAVE___func__) 
# ifndef __func__ 
#  define __func__ __func__ 
# endif 
#elif defined(EVENT__HAVE___FUNCTION__) 
# define __func__ __FUNCTION__ 
#else 
# define __func__ __FILE__ 
#endif

/* A good no-op to use in macro definitions. */
#define EVUTIL_NIL_STMT_ ((void)0) 
/* A no-op that tricks the compiler into thinking a condition is used while
 * definitely not making any code for it.  Used to compile out asserts while
 * avoiding "unused variable" warnings.  The "!" forces the compiler to
 * do the sizeof() on an int, in case "condition" is a bitfield value.
 */
#define EVUTIL_NIL_CONDITION_(condition) do { \ 
	(void)sizeof(!(condition));  \
} while(0)

/* Internal use only: macros to match patterns of error codes in a
   cross-platform way.  We need these macros because of two historical
   reasons: first, nonblocking IO functions are generally written to give an
   error on the "blocked now, try later" case, so sometimes an error from a
   read, write, connect, or accept means "no error; just wait for more
   data," and we need to look at the error code.  Second, Windows defines
   a different set of error codes for sockets. */

#ifndef _WIN32 

#if EAGAIN == EWOULDBLOCK 
#define EVUTIL_ERR_IS_EAGAIN(e) \ 
	((e) == EAGAIN) 
#else 
#define EVUTIL_ERR_IS_EAGAIN(e) \ 
	((e) == EAGAIN || (e) == EWOULDBLOCK) 
#endif 
 
/* True iff e is an error that means a read/write operation can be retried. */
#define EVUTIL_ERR_RW_RETRIABLE(e)				\
	((e) == EINTR || EVUTIL_ERR_IS_EAGAIN(e)) 
/* True iff e is an error that means an connect can be retried. */
#define EVUTIL_ERR_CONNECT_RETRIABLE(e)			\
	((e) == EINTR || (e) == EINPROGRESS)
/* True iff e is an error that means a accept can be retried. */
#define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
	((e) == EINTR || EVUTIL_ERR_IS_EAGAIN(e) || (e) == ECONNABORTED) 

/* True iff e is an error that means the connection was refused */
#define EVUTIL_ERR_CONNECT_REFUSED(e)					\
	((e) == ECONNREFUSED)

#else
/* Win32 */ 

#define EVUTIL_ERR_IS_EAGAIN(e) \ 
	((e) == WSAEWOULDBLOCK || (e) == EAGAIN) 
 
#define EVUTIL_ERR_RW_RETRIABLE(e)					\
	((e) == WSAEWOULDBLOCK ||					\
	    (e) == WSAEINTR)

#define EVUTIL_ERR_CONNECT_RETRIABLE(e)					\
	((e) == WSAEWOULDBLOCK ||					\
	    (e) == WSAEINTR ||						\
	    (e) == WSAEINPROGRESS ||					\
	    (e) == WSAEINVAL)

#define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
	EVUTIL_ERR_RW_RETRIABLE(e)

#define EVUTIL_ERR_CONNECT_REFUSED(e)					\
	((e) == WSAECONNREFUSED)

#endif

/* Arguments for shutdown() */
#ifdef SHUT_RD
#define EVUTIL_SHUT_RD SHUT_RD
#else
#define EVUTIL_SHUT_RD 0
#endif
#ifdef SHUT_WR
#define EVUTIL_SHUT_WR SHUT_WR
#else
#define EVUTIL_SHUT_WR 1 /* SD_SEND */ 
#endif
#ifdef SHUT_BOTH
#define EVUTIL_SHUT_BOTH SHUT_BOTH
#else
#define EVUTIL_SHUT_BOTH 2
#endif

/* Helper: Verify that all the elements in 'dlist' are internally consistent. 
 * Checks for circular lists and bad prev/next pointers. 
 * 
 * Example usage: 
 *    EVUTIL_ASSERT_LIST_OK(eventlist, event, ev_next); 
 */ 
#define EVUTIL_ASSERT_LIST_OK(dlist, type, field) do {			\ 
		struct type *elm1, *elm2, **nextp;			\ 
		if (LIST_EMPTY((dlist)))				\ 
			break;						\ 
									\ 
		/* Check list for circularity using Floyd's */		\ 
		/* 'Tortoise and Hare' algorithm */			\ 
		elm1 = LIST_FIRST((dlist));				\ 
		elm2 = LIST_NEXT(elm1, field);				\ 
		while (elm1 && elm2) {					\ 
			EVUTIL_ASSERT(elm1 != elm2);			\ 
			elm1 = LIST_NEXT(elm1, field);			\ 
			elm2 = LIST_NEXT(elm2, field);			\ 
			if (!elm2)					\ 
				break;					\ 
			EVUTIL_ASSERT(elm1 != elm2);			\ 
			elm2 = LIST_NEXT(elm2, field);			\ 
		}							\ 
									\ 
		/* Now check next and prev pointers for consistency. */ \ 
		nextp = &LIST_FIRST((dlist));				\ 
		elm1 = LIST_FIRST((dlist));				\ 
		while (elm1) {						\ 
			EVUTIL_ASSERT(*nextp == elm1);			\ 
			EVUTIL_ASSERT(nextp == elm1->field.le_prev);	\ 
			nextp = &LIST_NEXT(elm1, field);		\ 
			elm1 = *nextp;					\ 
		}							\ 
	} while (0) 
 
/* Helper: Verify that all the elements in a TAILQ are internally consistent. 
 * Checks for circular lists and bad prev/next pointers. 
 * 
 * Example usage: 
 *    EVUTIL_ASSERT_TAILQ_OK(activelist, event, ev_active_next); 
 */ 
#define EVUTIL_ASSERT_TAILQ_OK(tailq, type, field) do {			\ 
		struct type *elm1, *elm2, **nextp;			\ 
		if (TAILQ_EMPTY((tailq)))				\ 
			break;						\ 
									\ 
		/* Check list for circularity using Floyd's */		\ 
		/* 'Tortoise and Hare' algorithm */			\ 
		elm1 = TAILQ_FIRST((tailq));				\ 
		elm2 = TAILQ_NEXT(elm1, field);				\ 
		while (elm1 && elm2) {					\ 
			EVUTIL_ASSERT(elm1 != elm2);			\ 
			elm1 = TAILQ_NEXT(elm1, field);			\ 
			elm2 = TAILQ_NEXT(elm2, field);			\ 
			if (!elm2)					\ 
				break;					\ 
			EVUTIL_ASSERT(elm1 != elm2);			\ 
			elm2 = TAILQ_NEXT(elm2, field);			\ 
		}							\ 
									\ 
		/* Now check next and prev pointers for consistency. */ \ 
		nextp = &TAILQ_FIRST((tailq));				\ 
		elm1 = TAILQ_FIRST((tailq));				\ 
		while (elm1) {						\ 
			EVUTIL_ASSERT(*nextp == elm1);			\ 
			EVUTIL_ASSERT(nextp == elm1->field.tqe_prev);	\ 
			nextp = &TAILQ_NEXT(elm1, field);		\ 
			elm1 = *nextp;					\ 
		}							\ 
		EVUTIL_ASSERT(nextp == (tailq)->tqh_last);		\ 
	} while (0) 
 
/* Locale-independent replacements for some ctypes functions.  Use these
 * when you care about ASCII's notion of character types, because you are about
 * to send those types onto the wire.
 */
EVENT2_EXPORT_SYMBOL 
int EVUTIL_ISALPHA_(char c); 
EVENT2_EXPORT_SYMBOL 
int EVUTIL_ISALNUM_(char c); 
int EVUTIL_ISSPACE_(char c); 
EVENT2_EXPORT_SYMBOL 
int EVUTIL_ISDIGIT_(char c); 
EVENT2_EXPORT_SYMBOL 
int EVUTIL_ISXDIGIT_(char c); 
int EVUTIL_ISPRINT_(char c); 
int EVUTIL_ISLOWER_(char c); 
int EVUTIL_ISUPPER_(char c); 
EVENT2_EXPORT_SYMBOL 
char EVUTIL_TOUPPER_(char c); 
EVENT2_EXPORT_SYMBOL 
char EVUTIL_TOLOWER_(char c); 

/** Remove all trailing horizontal whitespace (space or tab) from the end of a 
 * string */ 
EVENT2_EXPORT_SYMBOL 
void evutil_rtrim_lws_(char *); 
 
 
/** Helper macro.  If we know that a given pointer points to a field in a
    structure, return a pointer to the structure itself.  Used to implement
    our half-baked C OO.  Example:

    struct subtype {
	int x;
	struct supertype common;
	int y;
    };
    ...
    void fn(struct supertype *super) {
	struct subtype *sub = EVUTIL_UPCAST(super, struct subtype, common);
	...
    }
 */
#define EVUTIL_UPCAST(ptr, type, field)				\
	((type *)(((char*)(ptr)) - evutil_offsetof(type, field)))

/* As open(pathname, flags, mode), except that the file is always opened with
 * the close-on-exec flag set. (And the mode argument is mandatory.)
 */
int evutil_open_closeonexec_(const char *pathname, int flags, unsigned mode); 

EVENT2_EXPORT_SYMBOL 
int evutil_read_file_(const char *filename, char **content_out, size_t *len_out, 
    int is_binary);

EVENT2_EXPORT_SYMBOL 
int evutil_socket_connect_(evutil_socket_t *fd_ptr, const struct sockaddr *sa, int socklen); 

int evutil_socket_finished_connecting_(evutil_socket_t fd); 

EVENT2_EXPORT_SYMBOL 
int evutil_ersatz_socketpair_(int, int , int, evutil_socket_t[]); 

int evutil_resolve_(int family, const char *hostname, struct sockaddr *sa, 
    ev_socklen_t *socklen, int port);

const char *evutil_getenv_(const char *name); 

/* Structure to hold the state of our weak random number generator. 
 */ 
struct evutil_weakrand_state { 
	ev_uint32_t seed; 
}; 

#define EVUTIL_WEAKRAND_MAX EV_INT32_MAX 
 
/* Initialize the state of a week random number generator based on 'seed'.  If 
 * the seed is 0, construct a new seed based on not-very-strong platform 
 * entropy, like the PID and the time of day. 
 * 
 * This function, and the other evutil_weakrand* functions, are meant for 
 * speed, not security or statistical strength.  If you need a RNG which an 
 * attacker can't predict, or which passes strong statistical tests, use the 
 * evutil_secure_rng* functions instead. 
 */ 
EVENT2_EXPORT_SYMBOL 
ev_uint32_t evutil_weakrand_seed_(struct evutil_weakrand_state *state, ev_uint32_t seed); 
/* Return a pseudorandom value between 0 and EVUTIL_WEAKRAND_MAX inclusive. 
 * Updates the state in 'seed' as needed -- this value must be protected by a 
 * lock. 
 */ 
EVENT2_EXPORT_SYMBOL 
ev_int32_t evutil_weakrand_(struct evutil_weakrand_state *seed); 
/* Return a pseudorandom value x such that 0 <= x < top. top must be no more 
 * than EVUTIL_WEAKRAND_MAX. Updates the state in 'seed' as needed -- this 
 * value must be proteced by a lock */ 
EVENT2_EXPORT_SYMBOL 
ev_int32_t evutil_weakrand_range_(struct evutil_weakrand_state *seed, ev_int32_t top); 
 
/* Evaluates to the same boolean value as 'p', and hints to the compiler that
 * we expect this value to be false. */
#if defined(__GNUC__) && __GNUC__ >= 3         /* gcc 3.0 or later */
#define EVUTIL_UNLIKELY(p) __builtin_expect(!!(p),0)
#else
#define EVUTIL_UNLIKELY(p) (p)
#endif

#if EVUTIL_HAS_ATTRIBUTE(fallthrough) 
#define EVUTIL_FALLTHROUGH __attribute__((fallthrough)) 
#else 
#define EVUTIL_FALLTHROUGH /* fallthrough */ 
#endif 
 
/* Replacement for assert() that calls event_errx on failure. */
#ifdef NDEBUG
#define EVUTIL_ASSERT(cond) EVUTIL_NIL_CONDITION_(cond) 
#define EVUTIL_FAILURE_CHECK(cond) 0
#else
#define EVUTIL_ASSERT(cond)						\
	do {								\
		if (EVUTIL_UNLIKELY(!(cond))) {				\
			event_errx(EVENT_ERR_ABORT_,			\ 
			    "%s:%d: Assertion %s failed in %s",		\
			    __FILE__,__LINE__,#cond,__func__);		\
			/* In case a user-supplied handler tries to */	\
			/* return control to us, log and abort here. */	\
			(void)fprintf(stderr,				\
			    "%s:%d: Assertion %s failed in %s",		\
			    __FILE__,__LINE__,#cond,__func__);		\
			abort();					\
		}							\
	} while (0)
#define EVUTIL_FAILURE_CHECK(cond) EVUTIL_UNLIKELY(cond)
#endif

#ifndef EVENT__HAVE_STRUCT_SOCKADDR_STORAGE 
/* Replacement for sockaddr storage that we can use internally on platforms
 * that lack it.  It is not space-efficient, but neither is sockaddr_storage.
 */
struct sockaddr_storage {
	union {
		struct sockaddr ss_sa;
		struct sockaddr_in ss_sin;
		struct sockaddr_in6 ss_sin6;
		char ss_padding[128];
	} ss_union;
};
#define ss_family ss_union.ss_sa.sa_family
#endif

/* Internal addrinfo error code.  This one is returned from only from
 * evutil_getaddrinfo_common_, when we are sure that we'll have to hit a DNS 
 * server. */
#define EVUTIL_EAI_NEED_RESOLVE      -90002

struct evdns_base;
struct evdns_getaddrinfo_request;
typedef struct evdns_getaddrinfo_request* (*evdns_getaddrinfo_fn)(
    struct evdns_base *base,
    const char *nodename, const char *servname,
    const struct evutil_addrinfo *hints_in,
    void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
EVENT2_EXPORT_SYMBOL 
void evutil_set_evdns_getaddrinfo_fn_(evdns_getaddrinfo_fn fn); 
typedef void (*evdns_getaddrinfo_cancel_fn)( 
    struct evdns_getaddrinfo_request *req); 
EVENT2_EXPORT_SYMBOL 
void evutil_set_evdns_getaddrinfo_cancel_fn_(evdns_getaddrinfo_cancel_fn fn); 

EVENT2_EXPORT_SYMBOL 
struct evutil_addrinfo *evutil_new_addrinfo_(struct sockaddr *sa, 
    ev_socklen_t socklen, const struct evutil_addrinfo *hints);
EVENT2_EXPORT_SYMBOL 
struct evutil_addrinfo *evutil_addrinfo_append_(struct evutil_addrinfo *first, 
    struct evutil_addrinfo *append);
EVENT2_EXPORT_SYMBOL 
void evutil_adjust_hints_for_addrconfig_(struct evutil_addrinfo *hints); 
EVENT2_EXPORT_SYMBOL 
int evutil_getaddrinfo_common_(const char *nodename, const char *servname, 
    struct evutil_addrinfo *hints, struct evutil_addrinfo **res, int *portnum);

struct evdns_getaddrinfo_request *evutil_getaddrinfo_async_( 
    struct evdns_base *dns_base, 
    const char *nodename, const char *servname,
    const struct evutil_addrinfo *hints_in,
    void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
void evutil_getaddrinfo_cancel_async_(struct evdns_getaddrinfo_request *data); 

/** Return true iff sa is a looback address. (That is, it is 127.0.0.1/8, or
 * ::1). */
EVENT2_EXPORT_SYMBOL 
int evutil_sockaddr_is_loopback_(const struct sockaddr *sa); 


/**
    Formats a sockaddr sa into a string buffer of size outlen stored in out.
    Returns a pointer to out.  Always writes something into out, so it's safe
    to use the output of this function without checking it for NULL.
 */
EVENT2_EXPORT_SYMBOL 
const char *evutil_format_sockaddr_port_(const struct sockaddr *sa, char *out, size_t outlen); 

int evutil_hex_char_to_int_(char c); 


void evutil_free_secure_rng_globals_(void); 
void evutil_free_globals_(void); 
 
#ifdef _WIN32 
EVENT2_EXPORT_SYMBOL 
HMODULE evutil_load_windows_system_library_(const TCHAR *library_name); 
#endif

#ifndef EV_SIZE_FMT
#if defined(_MSC_VER) || defined(__MINGW32__) || defined(__MINGW64__)
#define EV_U64_FMT "%I64u"
#define EV_I64_FMT "%I64d"
#define EV_I64_ARG(x) ((__int64)(x))
#define EV_U64_ARG(x) ((unsigned __int64)(x))
#else
#define EV_U64_FMT "%llu"
#define EV_I64_FMT "%lld"
#define EV_I64_ARG(x) ((long long)(x))
#define EV_U64_ARG(x) ((unsigned long long)(x))
#endif
#endif

#ifdef _WIN32
#define EV_SOCK_FMT EV_I64_FMT
#define EV_SOCK_ARG(x) EV_I64_ARG((x))
#else
#define EV_SOCK_FMT "%d"
#define EV_SOCK_ARG(x) (x)
#endif

#if defined(__STDC__) && defined(__STDC_VERSION__) && !defined(__MINGW64_VERSION_MAJOR) 
#if (__STDC_VERSION__ >= 199901L)
#define EV_SIZE_FMT "%zu"
#define EV_SSIZE_FMT "%zd"
#define EV_SIZE_ARG(x) (x)
#define EV_SSIZE_ARG(x) (x)
#endif
#endif

#ifndef EV_SIZE_FMT
#if (EVENT__SIZEOF_SIZE_T <= EVENT__SIZEOF_LONG) 
#define EV_SIZE_FMT "%lu"
#define EV_SSIZE_FMT "%ld"
#define EV_SIZE_ARG(x) ((unsigned long)(x))
#define EV_SSIZE_ARG(x) ((long)(x))
#else
#define EV_SIZE_FMT EV_U64_FMT
#define EV_SSIZE_FMT EV_I64_FMT
#define EV_SIZE_ARG(x) EV_U64_ARG(x)
#define EV_SSIZE_ARG(x) EV_I64_ARG(x)
#endif
#endif

EVENT2_EXPORT_SYMBOL 
evutil_socket_t evutil_socket_(int domain, int type, int protocol); 
evutil_socket_t evutil_accept4_(evutil_socket_t sockfd, struct sockaddr *addr, 
    ev_socklen_t *addrlen, int flags); 
 
    /* used by one of the test programs.. */ 
EVENT2_EXPORT_SYMBOL 
int evutil_make_internal_pipe_(evutil_socket_t fd[2]); 
evutil_socket_t evutil_eventfd_(unsigned initval, int flags); 
 
#ifdef SOCK_NONBLOCK 
#define EVUTIL_SOCK_NONBLOCK SOCK_NONBLOCK 
#else 
#define EVUTIL_SOCK_NONBLOCK 0x4000000 
#endif 
#ifdef SOCK_CLOEXEC 
#define EVUTIL_SOCK_CLOEXEC SOCK_CLOEXEC 
#else 
#define EVUTIL_SOCK_CLOEXEC 0x80000000 
#endif 
#ifdef EFD_NONBLOCK 
#define EVUTIL_EFD_NONBLOCK EFD_NONBLOCK 
#else 
#define EVUTIL_EFD_NONBLOCK 0x4000 
#endif 
#ifdef EFD_CLOEXEC 
#define EVUTIL_EFD_CLOEXEC EFD_CLOEXEC 
#else 
#define EVUTIL_EFD_CLOEXEC 0x8000 
#endif 
 
void evutil_memclear_(void *mem, size_t len);

struct in_addr; 
struct in6_addr; 
 
/* This is a any, loopback, link-local, multicast */ 
EVENT2_EXPORT_SYMBOL 
int evutil_v4addr_is_local_(const struct in_addr *in); 
/* This is a reserved, ipv4compat, ipv4map, loopback, 
 * link-local, multicast, or unspecified address. */ 
EVENT2_EXPORT_SYMBOL 
int evutil_v6addr_is_local_(const struct in6_addr *in); 
 
#ifdef __cplusplus
}
#endif

#endif