wrapsock.c

《unix网络编程第二卷》中的源代码

/*
 * Socket wrapper functions.
 * These could all go into separate files, so only the ones needed cause
 * the corresponding function to be added to the executable.  If sockets
 * are a library (SVR4) this might make a difference (?), but if sockets
 * are in the kernel (BSD) it doesn't matter.
 *
 * These wrapper functions also use the same prototypes as POSIX.1g,
 * which might differ from many implementations (i.e., POSIX.1g specifies
 * the fourth argument to getsockopt() as "void *", not "char *").
 *
 * If your system's headers are not correct [i.e., the Solaris 2.5
 * <sys/socket.h> omits the "const" from the second argument to both
 * bind() and connect()], you'll get warnings of the form:
 *warning: passing arg 2 of `bind' discards `const' from pointer target type
 *warning: passing arg 2 of `connect' discards `const' from pointer target type
 */

#include	"unp.h"

int
Accept(int fd, struct sockaddr *sa, socklen_t *salenptr)
{
	int		n;

again:
	if ( (n = accept(fd, sa, salenptr)) < 0) {
#ifdef	EPROTO
		if (errno == EPROTO || errno == ECONNABORTED)
#else
		if (errno == ECONNABORTED)
#endif
			goto again;
		else
			err_sys("accept error");
	}
	return(n);
}

void
Bind(int fd, const struct sockaddr *sa, socklen_t salen)
{
	if (bind(fd, sa, salen) < 0)
		err_sys("bind error");
}

void
Connect(int fd, const struct sockaddr *sa, socklen_t salen)
{
	if (connect(fd, sa, salen) < 0)
		err_sys("connect error");
}

void
Getpeername(int fd, struct sockaddr *sa, socklen_t *salenptr)
{
	if (getpeername(fd, sa, salenptr) < 0)
		err_sys("getpeername error");
}

void
Getsockname(int fd, struct sockaddr *sa, socklen_t *salenptr)
{
	if (getsockname(fd, sa, salenptr) < 0)
		err_sys("getsockname error");
}

void
Getsockopt(int fd, int level, int optname, void *optval, socklen_t *optlenptr)
{
	if (getsockopt(fd, level, optname, optval, optlenptr) < 0)
		err_sys("getsockopt error");
}

int
Isfdtype(int fd, int fdtype)
{
	int		n;

	if ( (n = isfdtype(fd, fdtype)) < 0)
		err_sys("isfdtype error");
	return(n);
}

/* include Listen */
void
Listen(int fd, int backlog)
{
	char	*ptr;

		/*4can override 2nd argument with environment variable */
	if ( (ptr = getenv("LISTENQ")) != NULL)
		backlog = atoi(ptr);

	if (listen(fd, backlog) < 0)
		err_sys("listen error");
}
/* end Listen */

#ifdef	HAVE_POLL
int
Poll(struct pollfd *fdarray, unsigned long nfds, int timeout)
{
	int		n;

	if ( (n = poll(fdarray, nfds, timeout)) < 0)
		err_sys("poll error");

	return(n);
}
#endif

ssize_t
Recv(int fd, void *ptr, size_t nbytes, int flags)
{
	ssize_t		n;

	if ( (n = recv(fd, ptr, nbytes, flags)) < 0)
		err_sys("recv error");
	return(n);
}

ssize_t
Recvfrom(int fd, void *ptr, size_t nbytes, int flags,
		 struct sockaddr *sa, socklen_t *salenptr)
{
	ssize_t		n;

	if ( (n = recvfrom(fd, ptr, nbytes, flags, sa, salenptr)) < 0)
		err_sys("recvfrom error");
	return(n);
}

ssize_t
Recvmsg(int fd, struct msghdr *msg, int flags)
{
	ssize_t		n;

	if ( (n = recvmsg(fd, msg, flags)) < 0)
		err_sys("recvmsg error");
	return(n);
}

int
Select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
       struct timeval *timeout)
{
	int		n;

	if ( (n = select(nfds, readfds, writefds, exceptfds, timeout)) < 0)
		err_sys("select error");
	return(n);		/* can return 0 on timeout */
}

void
Send(int fd, const void *ptr, size_t nbytes, int flags)
{
	if (send(fd, ptr, nbytes, flags) != nbytes)
		err_sys("send error");
}

void
Sendto(int fd, const void *ptr, size_t nbytes, int flags,
	   const struct sockaddr *sa, socklen_t salen)
{
	if (sendto(fd, ptr, nbytes, flags, sa, salen) != nbytes)
		err_sys("sendto error");
}

void
Sendmsg(int fd, const struct msghdr *msg, int flags)
{
	int			i;
	ssize_t		nbytes;

	nbytes = 0;	/* must first figure out what return value should be */
	for (i = 0; i < msg->msg_iovlen; i++)
		nbytes += msg->msg_iov[i].iov_len;

	if (sendmsg(fd, msg, flags) != nbytes)
		err_sys("sendmsg error");
}

void
Setsockopt(int fd, int level, int optname, const void *optval, socklen_t optlen)
{
	if (setsockopt(fd, level, optname, optval, optlen) < 0)
		err_sys("setsockopt error");
}

void
Shutdown(int fd, int how)
{
	if (shutdown(fd, how) < 0)
		err_sys("shutdown error");
}

int
Sockatmark(int fd)
{
	int		n;

	if ( (n = sockatmark(fd)) < 0)
		err_sys("sockatmark error");
	return(n);
}

/* include Socket */
int
Socket(int family, int type, int protocol)
{
	int		n;

	if ( (n = socket(family, type, protocol)) < 0)
		err_sys("socket error");
	return(n);
}
/* end Socket */

void
Socketpair(int family, int type, int protocol, int *fd)
{
	int		n;

	if ( (n = socketpair(family, type, protocol, fd)) < 0)
		err_sys("socketpair error");
}