1 #include "toys.h" 2 3 int xsocket(int domain, int type, int protocol) 4 { 5 int fd = socket(domain, type, protocol); 6 7 if (fd < 0) perror_exit("socket %x %x", type, protocol); 8 fcntl(fd, F_SETFD, FD_CLOEXEC); 9 10 return fd; 11 } 12 13 void xsetsockopt(int fd, int level, int opt, void *val, socklen_t len) 14 { 15 if (-1 == setsockopt(fd, level, opt, val, len)) perror_exit("setsockopt"); 16 } 17 18 int xconnect(char *host, char *port, int family, int socktype, int protocol, 19 int flags) 20 { 21 struct addrinfo info, *ai, *ai2; 22 int fd; 23 24 memset(&info, 0, sizeof(struct addrinfo)); 25 info.ai_family = family; 26 info.ai_socktype = socktype; 27 info.ai_protocol = protocol; 28 info.ai_flags = flags; 29 30 fd = getaddrinfo(host, port, &info, &ai); 31 if (fd || !ai) 32 error_exit("Connect '%s%s%s': %s", host, port ? ":" : "", port ? port : "", 33 fd ? gai_strerror(fd) : "not found"); 34 35 // Try all the returned addresses. Report errors if last entry can't connect. 36 for (ai2 = ai; ai; ai = ai->ai_next) { 37 fd = (ai->ai_next ? socket : xsocket)(ai->ai_family, ai->ai_socktype, 38 ai->ai_protocol); 39 if (!connect(fd, ai->ai_addr, ai->ai_addrlen)) break; 40 else if (!ai->ai_next) perror_exit("connect"); 41 close(fd); 42 } 43 freeaddrinfo(ai2); 44 45 return fd; 46 } 47 48 int xpoll(struct pollfd *fds, int nfds, int timeout) 49 { 50 int i; 51 52 for (;;) { 53 if (0>(i = poll(fds, nfds, timeout))) { 54 if (toys.signal) return i; 55 if (errno != EINTR && errno != ENOMEM) perror_exit("xpoll"); 56 else if (timeout>0) timeout--; 57 } else return i; 58 } 59 } 60 61 // Loop forwarding data from in1 to out1 and in2 to out2, handling 62 // half-connection shutdown. timeouts return if no data for X miliseconds. 63 // Returns 0: both closed, 1 shutdown_timeout, 2 timeout 64 int pollinate(int in1, int in2, int out1, int out2, int timeout, int shutdown_timeout) 65 { 66 struct pollfd pollfds[2]; 67 int i, pollcount = 2; 68 69 memset(pollfds, 0, 2*sizeof(struct pollfd)); 70 pollfds[0].events = pollfds[1].events = POLLIN; 71 pollfds[0].fd = in1; 72 pollfds[1].fd = in2; 73 74 // Poll loop copying data from each fd to the other one. 75 for (;;) { 76 if (!xpoll(pollfds, pollcount, timeout)) return pollcount; 77 78 for (i=0; i<pollcount; i++) { 79 if (pollfds[i].revents & POLLIN) { 80 int len = read(pollfds[i].fd, libbuf, sizeof(libbuf)); 81 if (len<1) pollfds[i].revents = POLLHUP; 82 else xwrite(i ? out2 : out1, libbuf, len); 83 } 84 if (pollfds[i].revents & POLLHUP) { 85 // Close half-connection. This is needed for things like 86 // "echo GET / | netcat landley.net 80" 87 // Note that in1 closing triggers timeout, in2 returns now. 88 if (i) { 89 shutdown(pollfds[0].fd, SHUT_WR); 90 pollcount--; 91 timeout = shutdown_timeout; 92 } else return 0; 93 } 94 } 95 } 96 } 97