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#include "toys.h"
int xsocket(int domain, int type, int protocol)
{
int fd = socket(domain, type, protocol);
if (fd < 0) perror_exit("socket %x %x", type, protocol);
fcntl(fd, F_SETFD, FD_CLOEXEC);
return fd;
}
void xsetsockopt(int fd, int level, int opt, void *val, socklen_t len)
{
if (-1 == setsockopt(fd, level, opt, val, len)) perror_exit("setsockopt");
}
int xconnect(char *host, char *port, int family, int socktype, int protocol,
int flags)
{
struct addrinfo info, *ai, *ai2;
int fd;
memset(&info, 0, sizeof(struct addrinfo));
info.ai_family = family;
info.ai_socktype = socktype;
info.ai_protocol = protocol;
info.ai_flags = flags;
fd = getaddrinfo(host, port, &info, &ai);
if (fd || !ai)
error_exit("Connect '%s%s%s': %s", host, port ? ":" : "", port ? port : "",
fd ? gai_strerror(fd) : "not found");
// Try all the returned addresses. Report errors if last entry can't connect.
for (ai2 = ai; ai; ai = ai->ai_next) {
fd = (ai->ai_next ? socket : xsocket)(ai->ai_family, ai->ai_socktype,
ai->ai_protocol);
if (!connect(fd, ai->ai_addr, ai->ai_addrlen)) break;
else if (!ai->ai_next) perror_exit("connect");
close(fd);
}
freeaddrinfo(ai2);
return fd;
}
int xpoll(struct pollfd *fds, int nfds, int timeout)
{
int i;
for (;;) {
if (0>(i = poll(fds, nfds, timeout))) {
if (toys.signal) return i;
if (errno != EINTR && errno != ENOMEM) perror_exit("xpoll");
else if (timeout>0) timeout--;
} else return i;
}
}
// Loop forwarding data from in1 to out1 and in2 to out2, handling
// half-connection shutdown. timeouts return if no data for X miliseconds.
// Returns 0: both closed, 1 shutdown_timeout, 2 timeout
int pollinate(int in1, int in2, int out1, int out2, int timeout, int shutdown_timeout)
{
struct pollfd pollfds[2];
int i, pollcount = 2;
memset(pollfds, 0, 2*sizeof(struct pollfd));
pollfds[0].events = pollfds[1].events = POLLIN;
pollfds[0].fd = in1;
pollfds[1].fd = in2;
// Poll loop copying data from each fd to the other one.
for (;;) {
if (!xpoll(pollfds, pollcount, timeout)) return pollcount;
for (i=0; i<pollcount; i++) {
if (pollfds[i].revents & POLLIN) {
int len = read(pollfds[i].fd, libbuf, sizeof(libbuf));
if (len<1) pollfds[i].revents = POLLHUP;
else xwrite(i ? out2 : out1, libbuf, len);
}
if (pollfds[i].revents & POLLHUP) {
// Close half-connection. This is needed for things like
// "echo GET / | netcat landley.net 80"
// Note that in1 closing triggers timeout, in2 returns now.
if (i) {
shutdown(pollfds[0].fd, SHUT_WR);
pollcount--;
timeout = shutdown_timeout;
} else return 0;
}
}
}
}
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