Common convenience functions for cross-platform portability and related socket manipulations. More...

#include <event2/visibility.h>
#include <event2/event-config.h>
#include <stdarg.h>
#include <sys/socket.h>
#include <time.h>

Data Structures
struct	evutil_addrinfo
	A definition of struct addrinfo for systems that lack it. More...

struct	evutil_monotonic_timer
	Structure to hold information about a monotonic timer. More...

Macros
#define	EV_MONOT_FALLBACK 2

#define	EV_MONOT_PRECISE 1

#define	ev_socklen_t socklen_t

#define	EVUTIL_CLOSESOCKET(s) evutil_closesocket(s)

#define	evutil_offsetof(type, field) ((off_t)(&((type *)0)->field))
	Replacement for offsetof on platforms that don't define it.

#define	evutil_socket_t int
	A type wide enough to hold the output of "socket()" or "accept()". More...

#define	evutil_timercmp(tvp, uvp, cmp)
	Return true iff the tvp is related to uvp according to the relational operator cmp. More...

#define	evutil_timerisset(tvp) ((tvp)->tv_sec \|\| (tvp)->tv_usec)

Standard integer types.
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 (If you are on a platform like this, your C headers are now over 10 years out of date.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. ev_ssize_t A signed type of the same size as size_t ev_off_t A signed type typically used to represent offsets within a (potentially large) file
#define	ev_int16_t ...

#define	ev_int32_t ...

#define	ev_int64_t ...

#define	ev_int8_t ...

#define	ev_intptr_t ev_int32_t

#define	ev_off_t ...

#define	ev_ssize_t ssize_t

#define	ev_uint16_t ...

#define	ev_uint32_t ...

#define	ev_uint64_t ...

#define	ev_uint8_t ...

#define	ev_uintptr_t ev_uint32_t

Limits for integer types
These macros hold the largest or smallest values possible for the ev_[u]int*_t types.
#define	EV_INT16_MAX ((ev_int16_t) 0x7fffL)

#define	EV_INT16_MIN ((-EV_INT16_MAX) - 1)

#define	EV_INT32_MAX ((ev_int32_t) 0x7fffffffL)

#define	EV_INT32_MIN ((-EV_INT32_MAX) - 1)

#define	EV_INT64_MAX ((((ev_int64_t) 0x7fffffffL) << 32) \| 0xffffffffL)

#define	EV_INT64_MIN ((-EV_INT64_MAX) - 1)

#define	EV_INT8_MAX 127

#define	EV_INT8_MIN ((-EV_INT8_MAX) - 1)

#define	EV_UINT16_MAX ((ev_uint16_t)0xffffUL)

#define	EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL)

#define	EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) \| 0xffffffffUL)

#define	EV_UINT8_MAX 255

Limits for SIZE_T and SSIZE_T
#define	EV_SIZE_MAX ...

#define	EV_SSIZE_MAX ...

#define	EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1)

Socket error functions
These functions are needed for making programs compatible between Windows and Unix-like platforms. You see, 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.
#define	EVUTIL_INVALID_SOCKET -1

#define	EVUTIL_SET_SOCKET_ERROR(errcode) ...
	Replace the most recent socket error with errcode.

#define	EVUTIL_SOCKET_ERROR() ...
	Return the most recent socket error. More...

#define	evutil_socket_error_to_string(errcode) ...
	Convert a socket error to a string.

#define	evutil_socket_geterror(sock) ...
	Return the most recent socket error to occur on sock.

Manipulation macros for struct timeval.
We define replacements for timeradd, timersub, timerclear, timercmp, and timerisset.
#define	evutil_timeradd(tvp, uvp, vvp)

#define	evutil_timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0

#define	evutil_timersub(tvp, uvp, vvp)

evutil_getaddrinfo() error codes
These values are possible error codes for evutil_getaddrinfo() and related functions.
#define	EVUTIL_AI_ADDRCONFIG 0x40000

#define	EVUTIL_AI_ALL 0x20000

#define	EVUTIL_AI_CANONNAME 0x2000

#define	EVUTIL_AI_NUMERICHOST 0x4000

#define	EVUTIL_AI_NUMERICSERV 0x8000

#define	EVUTIL_AI_PASSIVE 0x1000

#define	EVUTIL_AI_V4MAPPED 0x10000

#define	EVUTIL_EAI_ADDRFAMILY -901

#define	EVUTIL_EAI_AGAIN -902

#define	EVUTIL_EAI_BADFLAGS -903

#define	EVUTIL_EAI_CANCEL -90001

#define	EVUTIL_EAI_FAIL -904

#define	EVUTIL_EAI_FAMILY -905

#define	EVUTIL_EAI_MEMORY -906

#define	EVUTIL_EAI_NODATA -907

#define	EVUTIL_EAI_NONAME -908

#define	EVUTIL_EAI_SERVICE -909

#define	EVUTIL_EAI_SOCKTYPE -910

#define	EVUTIL_EAI_SYSTEM -911

Functions
EVENT2_EXPORT_SYMBOL int	evutil_ascii_strcasecmp (const char str1, const char str2)
	As strcasecmp, but always compares the characters in locale-independent ASCII. More...

EVENT2_EXPORT_SYMBOL int	evutil_ascii_strncasecmp (const char str1, const char str2, size_t n)
	As strncasecmp, but always compares the characters in locale-independent ASCII. More...

EVENT2_EXPORT_SYMBOL int	evutil_closesocket (evutil_socket_t sock)
	Do the platform-specific call needed to close a socket returned from socket() or accept(). More...

EVENT2_EXPORT_SYMBOL int	evutil_configure_monotonic_time (struct evutil_monotonic_timer *timer, int flags)
	Set up a struct evutil_monotonic_timer; flags can include EV_MONOT_PRECISE and EV_MONOT_FALLBACK.

EVENT2_EXPORT_SYMBOL int	evutil_date_rfc1123 (char date, const size_t datelen, const struct tm tm)
	Format a date string using RFC 1123 format (used in HTTP). More...

EVENT2_EXPORT_SYMBOL void	evutil_freeaddrinfo (struct evutil_addrinfo *ai)
	Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo.

const EVENT2_EXPORT_SYMBOL char *	evutil_gai_strerror (int err)

EVENT2_EXPORT_SYMBOL int	evutil_getaddrinfo (const char nodename, const char servname, const struct evutil_addrinfo hints_in, struct evutil_addrinfo *res)
	This function clones getaddrinfo for systems that don't have it. More...

EVENT2_EXPORT_SYMBOL int	evutil_gettime_monotonic (struct evutil_monotonic_timer timer, struct timeval tp)
	Query the current monotonic time from a struct evutil_monotonic_timer previously configured with evutil_configure_monotonic_time(). More...

EVENT2_EXPORT_SYMBOL int	evutil_gettimeofday (struct timeval tv, struct timezone tz)

const EVENT2_EXPORT_SYMBOL char *	evutil_inet_ntop (int af, const void src, char dst, size_t len)
	Replacement for inet_ntop for platforms which lack it. More...

EVENT2_EXPORT_SYMBOL int	evutil_inet_pton (int af, const char src, void dst)
	Replacement for inet_pton for platforms which lack it. More...

EVENT2_EXPORT_SYMBOL int	evutil_inet_pton_scope (int af, const char src, void dst, unsigned *indexp)
	Variation of inet_pton that also parses IPv6 scopes. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_listen_socket_ipv6only (evutil_socket_t sock)
	Set ipv6 only bind socket option to make listener work only in ipv6 sockets. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_listen_socket_not_ipv6only (evutil_socket_t sock)
	Set ipv6 only bind socket option to make listener work in both ipv4 and ipv6 sockets. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_listen_socket_reuseable (evutil_socket_t sock)
	Do platform-specific operations to make a listener socket reusable. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_listen_socket_reuseable_port (evutil_socket_t sock)
	Do platform-specific operations to make a listener port reusable. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_socket_closeonexec (evutil_socket_t sock)
	Do platform-specific operations as needed to close a socket upon a successful execution of one of the exec*() functions. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_socket_nonblocking (evutil_socket_t sock)
	Do platform-specific operations as needed to make a socket nonblocking. More...

EVENT2_EXPORT_SYMBOL int	evutil_make_tcp_listen_socket_deferred (evutil_socket_t sock)
	Do platform-specific operations, if possible, to make a tcp listener socket defer accept()s until there is data to read. More...

EVENT2_EXPORT_SYMBOL void	evutil_monotonic_timer_free (struct evutil_monotonic_timer *timer)
	Free a struct evutil_monotonic_timer that was allocated using evutil_monotonic_timer_new().

EVENT2_EXPORT_SYMBOL struct evutil_monotonic_timer *	evutil_monotonic_timer_new (void)
	Allocate a new struct evutil_monotonic_timer for use with the evutil_configure_monotonic_time() and evutil_gettime_monotonic() functions. More...

EVENT2_EXPORT_SYMBOL int	evutil_parse_sockaddr_port (const char str, struct sockaddr out, int *outlen)
	Parse an IPv4 or IPv6 address, with optional port, from a string. More...

EVENT2_EXPORT_SYMBOL void	evutil_secure_rng_add_bytes (const char *dat, size_t datlen)
	Seed the random number generator with extra random bytes. More...

EVENT2_EXPORT_SYMBOL void	evutil_secure_rng_get_bytes (void *buf, size_t n)
	Generate n bytes of secure pseudorandom data, and store them in buf. More...

EVENT2_EXPORT_SYMBOL int	evutil_secure_rng_init (void)
	Seed the secure random number generator if needed, and return 0 on success or -1 on failure. More...

EVENT2_EXPORT_SYMBOL int	evutil_secure_rng_set_urandom_device_file (char *fname)
	Set a filename to use in place of /dev/urandom for seeding the secure PRNG. More...

EVENT2_EXPORT_SYMBOL int	evutil_set_tcp_keepalive (evutil_socket_t sock, int on, int timeout)
	Do platform-specific operations to set/unset TCP keep-alive options TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT on a socket. More...

EVENT2_EXPORT_SYMBOL int	evutil_snprintf (char buf, size_t buflen, const char format,...)
	Replacement for snprintf to get consistent behavior on platforms for which the return value of snprintf does not conform to C99.

EVENT2_EXPORT_SYMBOL int	evutil_sockaddr_cmp (const struct sockaddr sa1, const struct sockaddr sa2, int include_port)
	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. More...

EVENT2_EXPORT_SYMBOL int	evutil_socketpair (int domain, int type, int protocol, evutil_socket_t sv[2])
	Create two new sockets that are connected to each other. More...

EVENT2_EXPORT_SYMBOL ev_int64_t	evutil_strtoll (const char s, char *endptr, int base)
	Parse a 64-bit value from a string. More...

EVENT2_EXPORT_SYMBOL int	evutil_vsnprintf (char buf, size_t buflen, const char format, va_list ap)
	Replacement for vsnprintf to get consistent behavior on platforms for which the return value of snprintf does not conform to C99.

Detailed Description

Common convenience functions for cross-platform portability and related socket manipulations.

Macro Definition Documentation

◆ EVUTIL_SOCKET_ERROR

#define EVUTIL_SOCKET_ERROR ( ) ...

Return the most recent socket error.

Not idempotent on all platforms.

◆ evutil_socket_t

#define evutil_socket_t int

A type wide enough to hold the output of "socket()" or "accept()".

On Windows, this is an intptr_t; elsewhere, it is an int.

◆ evutil_timeradd

#define evutil_timeradd	(	tvp,
		uvp,
		vvp
	)

Value:

    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)

◆ evutil_timercmp

#define evutil_timercmp	(	tvp,
		uvp,
		cmp
	)

Value:

    (((tvp)->tv_sec == (uvp)->tv_sec) ?             \
     ((tvp)->tv_usec cmp (uvp)->tv_usec) :              \
     ((tvp)->tv_sec cmp (uvp)->tv_sec))

Return true iff the tvp is related to uvp according to the relational operator cmp.

Recognized values for cmp are ==, <=, <, >=, and >.

◆ evutil_timersub

#define evutil_timersub	(	tvp,
		uvp,
		vvp
	)

Value:

    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)

Function Documentation

◆ evutil_ascii_strcasecmp()

EVENT2_EXPORT_SYMBOL int evutil_ascii_strcasecmp	(	const char *	str1,
		const char *	str2
	)

As strcasecmp, but always compares the characters in locale-independent ASCII.

That's useful if you're handling data in ASCII-based protocols. str1 and str2 must not be NULL.

◆ evutil_ascii_strncasecmp()

EVENT2_EXPORT_SYMBOL int evutil_ascii_strncasecmp	(	const char *	str1,
		const char *	str2,
		size_t	n
	)

As strncasecmp, but always compares the characters in locale-independent ASCII.

That's useful if you're handling data in ASCII-based protocols.

◆ evutil_closesocket()

EVENT2_EXPORT_SYMBOL int evutil_closesocket ( evutil_socket_t sock )

Do the platform-specific call needed to close a socket returned from socket() or accept().

Parameters

sock	The socket to be closed

Returns: 0 on success (whether the operation is supported or not), -1 on failure

◆ evutil_date_rfc1123()

EVENT2_EXPORT_SYMBOL int evutil_date_rfc1123	(	char *	date,
		const size_t	datelen,
		const struct tm *	tm
	)

Format a date string using RFC 1123 format (used in HTTP).

If tm is NULL, current system's time will be used. The number of characters written will be returned. One should check if the return value is smaller than datelen to check if the result is truncated or not.

◆ evutil_getaddrinfo()

EVENT2_EXPORT_SYMBOL int evutil_getaddrinfo	(	const char *	nodename,
		const char *	servname,
		const struct evutil_addrinfo *	hints_in,
		struct evutil_addrinfo **	res
	)

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.

◆ evutil_gettime_monotonic()

EVENT2_EXPORT_SYMBOL int evutil_gettime_monotonic	(	struct evutil_monotonic_timer *	timer,
		struct timeval *	tp
	)

Query the current monotonic time from a struct evutil_monotonic_timer previously configured with evutil_configure_monotonic_time().

Monotonic time is guaranteed never to run in reverse, but is not necessarily epoch- based, or relative to any other definite point. Use it to make reliable measurements of elapsed time between events even when the system time may be changed.

It is not safe to use this function on the same timer from multiple threads.

◆ evutil_inet_ntop()

const EVENT2_EXPORT_SYMBOL char* evutil_inet_ntop	(	int	af,
		const void *	src,
		char *	dst,
		size_t	len
	)

Replacement for inet_ntop for platforms which lack it.

src must not be NULL.

◆ evutil_inet_pton()

EVENT2_EXPORT_SYMBOL int evutil_inet_pton	(	int	af,
		const char *	src,
		void *	dst
	)

Replacement for inet_pton for platforms which lack it.

src must not be NULL.

◆ evutil_inet_pton_scope()

EVENT2_EXPORT_SYMBOL int evutil_inet_pton_scope	(	int	af,
		const char *	src,
		void *	dst,
		unsigned *	indexp
	)

Variation of inet_pton that also parses IPv6 scopes.

Public for unit tests. No reason to call this directly.

◆ evutil_make_listen_socket_ipv6only()

EVENT2_EXPORT_SYMBOL int evutil_make_listen_socket_ipv6only ( evutil_socket_t sock )

Set ipv6 only bind socket option to make listener work only in ipv6 sockets.

According to RFC3493 and most Linux distributions, default value for the sockets is to work in IPv4-mapped mode. In IPv4-mapped mode, it is not possible to bind same port from different IPv4 and IPv6 handlers.

On Windows the default value is instead to only work in IPv6 mode.

Parameters

sock	The socket to make in ipv6only working mode

Returns: 0 on success, -1 on failure

◆ evutil_make_listen_socket_not_ipv6only()

EVENT2_EXPORT_SYMBOL int evutil_make_listen_socket_not_ipv6only ( evutil_socket_t sock )

Set ipv6 only bind socket option to make listener work in both ipv4 and ipv6 sockets.

According to RFC3493 and most Linux distributions, default value for the sockets is to work in IPv4-mapped mode. In IPv4-mapped mode, it is not possible to bind same port from different IPv4 and IPv6 handlers.

On Windows the default value is instead to only work in IPv6 mode.

Parameters

sock	The socket to make in ipv6only working mode

Returns: 0 on success, -1 on failure

◆ evutil_make_listen_socket_reuseable()

EVENT2_EXPORT_SYMBOL int evutil_make_listen_socket_reuseable ( evutil_socket_t sock )

Do platform-specific operations to make a listener socket reusable.

Specifically, we want to make sure that another program will be able to bind this address right after we've closed the listener.

This differs from Windows's interpretation of "reusable", which allows multiple listeners to bind the same address at the same time.

Parameters

sock	The socket to make reusable

Returns: 0 on success, -1 on failure

◆ evutil_make_listen_socket_reuseable_port()

EVENT2_EXPORT_SYMBOL int evutil_make_listen_socket_reuseable_port ( evutil_socket_t sock )

Do platform-specific operations to make a listener port reusable.

Specifically, we want to make sure that multiple programs that also set the same socket option will be able to bind, and listen at the same time, for incoming connections/datagrams to be distributed evenly across all of the threads (or processes).

This feature is available only on Linux 3.9+, DragonFlyBSD 3.6+, FreeBSD 12.0+, Solaris 11.4, AIX 7.2.5 for now.

Parameters

sock	The socket to make reusable

Returns: 0 on success, -1 on failure

◆ evutil_make_socket_closeonexec()

EVENT2_EXPORT_SYMBOL int evutil_make_socket_closeonexec ( evutil_socket_t sock )

Do platform-specific operations as needed to close a socket upon a successful execution of one of the exec*() functions.

Parameters

sock	The socket to be closed

Returns: 0 on success, -1 on failure

◆ evutil_make_socket_nonblocking()

EVENT2_EXPORT_SYMBOL int evutil_make_socket_nonblocking ( evutil_socket_t sock )

Do platform-specific operations as needed to make a socket nonblocking.

Parameters

sock	The socket to make nonblocking

Returns: 0 on success, -1 on failure

◆ evutil_make_tcp_listen_socket_deferred()

EVENT2_EXPORT_SYMBOL int evutil_make_tcp_listen_socket_deferred ( evutil_socket_t sock )

Do platform-specific operations, if possible, to make a tcp listener socket defer accept()s until there is data to read.

Not all platforms support this. You don't want to do this for every listener socket: only the ones that implement a protocol where the client transmits before the server needs to respond.

Parameters

sock	The listening socket to make deferred

Returns: 0 on success (whether the operation is supported or not), -1 on failure

◆ evutil_monotonic_timer_new()

EVENT2_EXPORT_SYMBOL struct evutil_monotonic_timer* evutil_monotonic_timer_new ( void )

Allocate a new struct evutil_monotonic_timer for use with the evutil_configure_monotonic_time() and evutil_gettime_monotonic() functions.

You must configure the timer with evutil_configure_monotonic_time() before using it.

◆ evutil_parse_sockaddr_port()

EVENT2_EXPORT_SYMBOL int evutil_parse_sockaddr_port	(	const char *	str,
		struct sockaddr *	out,
		int *	outlen
	)

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.

Parameters

str	The string to parse.
out	A struct sockaddr to hold the result. This should probably be a struct sockaddr_storage.
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.

Returns: -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.

◆ evutil_secure_rng_add_bytes()

EVENT2_EXPORT_SYMBOL void evutil_secure_rng_add_bytes	(	const char *	dat,
		size_t	datlen
	)

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!

This function does nothing when the system provides arc4random() function because it will provide proper entropy.

Parameters

dat	a buffer full of a strong source of random numbers
datlen	the number of bytes to read from datlen

◆ evutil_secure_rng_get_bytes()

EVENT2_EXPORT_SYMBOL void evutil_secure_rng_get_bytes	(	void *	buf,
		size_t	n
	)

Generate n bytes of secure pseudorandom data, and store them in buf.

Current versions of Libevent use an ARC4-based random number generator, seeded using the platform's entropy source (/dev/urandom on Unix-like systems; BCryptGenRandom on Windows). This is not actually as secure as it should be: ARC4 is a pretty lousy cipher, and the current implementation provides only rudimentary prediction- and backtracking-resistance. Don't use this for serious cryptographic applications.

◆ evutil_secure_rng_init()

EVENT2_EXPORT_SYMBOL int evutil_secure_rng_init ( void )

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.

◆ evutil_secure_rng_set_urandom_device_file()

EVENT2_EXPORT_SYMBOL int evutil_secure_rng_set_urandom_device_file ( char * fname )

Set a filename to use in place of /dev/urandom for seeding the secure PRNG.

Return 0 on success, -1 on failure.

Call this function BEFORE calling any other initialization or RNG functions.

(This string will NOT be copied internally. Do not free it while any user of the secure RNG might be running. Don't pass anything other than a real /dev/...random device file here, or you might lose security.)

This API is unstable, and might change in a future libevent version.

◆ evutil_set_tcp_keepalive()

EVENT2_EXPORT_SYMBOL int evutil_set_tcp_keepalive	(	evutil_socket_t	sock,
		int	on,
		int	timeout
	)

Do platform-specific operations to set/unset TCP keep-alive options TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT on a socket.

Parameters

sock	The socket to be set TCP keep-alive
on	Nonzero value to enable TCP keep-alive, 0 to disable
timeout	The timeout in seconds with no activity until the first keepalive probe is sent

Returns: 0 on success, -1 on failure

◆ evutil_sockaddr_cmp()

EVENT2_EXPORT_SYMBOL int evutil_sockaddr_cmp	(	const struct sockaddr *	sa1,
		const struct sockaddr *	sa2,
		int	include_port
	)

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.

◆ evutil_socketpair()

EVENT2_EXPORT_SYMBOL int evutil_socketpair	(	int	domain,
		int	type,
		int	protocol,
		evutil_socket_t	sv[2]
	)

Create two new sockets that are connected to each other.

On Unix, this simply calls socketpair() and creates an unnamed pair of connected sockets in the specified domain, of the specified type, and using the optionally specified protocol.

On Windows, it will try to use the AF_UNIX to create unix socket pair if available, otherwise it instead uses AF_INET to create socket pair, binding the loopback network interface 127.0.0.1.

Including the bitwise OR of the EVUTIL_SOCK_NONBLOCK and/or EVUTIL_SOCK_CLOEXEC in the type argument will apply to both file descriptors.

(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()

◆ evutil_strtoll()

EVENT2_EXPORT_SYMBOL ev_int64_t evutil_strtoll	(	const char *	s,
		char **	endptr,
		int	base
	)

Parse a 64-bit value from a string.

Arguments are as for strtol.

Data Structures

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ EVUTIL_SOCKET_ERROR

◆ evutil_socket_t

◆ evutil_timeradd

◆ evutil_timercmp

◆ evutil_timersub

Function Documentation

◆ evutil_ascii_strcasecmp()

◆ evutil_ascii_strncasecmp()

◆ evutil_closesocket()

◆ evutil_date_rfc1123()

◆ evutil_getaddrinfo()

◆ evutil_gettime_monotonic()

◆ evutil_inet_ntop()

◆ evutil_inet_pton()

◆ evutil_inet_pton_scope()

◆ evutil_make_listen_socket_ipv6only()

◆ evutil_make_listen_socket_not_ipv6only()

◆ evutil_make_listen_socket_reuseable()

◆ evutil_make_listen_socket_reuseable_port()

◆ evutil_make_socket_closeonexec()

◆ evutil_make_socket_nonblocking()

◆ evutil_make_tcp_listen_socket_deferred()

◆ evutil_monotonic_timer_new()

◆ evutil_parse_sockaddr_port()

◆ evutil_secure_rng_add_bytes()

◆ evutil_secure_rng_get_bytes()

◆ evutil_secure_rng_init()

◆ evutil_secure_rng_set_urandom_device_file()

◆ evutil_set_tcp_keepalive()

◆ evutil_sockaddr_cmp()

◆ evutil_socketpair()

◆ evutil_strtoll()