X-Git-Url: http://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fnet%2Fnet.h;h=5e02fc36e7d09a329484ac5bfebf582c8c400cf3;hb=dded32f2b03fca526271e35671fa36d299880429;hp=456ca9d6d2052b624dbc450f25b4c33d1b732d77;hpb=04a42d50a02645aca83d7dc02d8e9838540e818d;p=ccan diff --git a/ccan/net/net.h b/ccan/net/net.h index 456ca9d6..5e02fc36 100644 --- a/ccan/net/net.h +++ b/ccan/net/net.h @@ -1,5 +1,10 @@ +/* Licensed under BSD-MIT - see LICENSE file for details */ #ifndef CCAN_NET_H #define CCAN_NET_H +#include + +struct pollfd; + /** * net_client_lookup - look up a network name to connect to. * @hostname: the name to look up @@ -15,6 +20,7 @@ * #include * #include * #include + * #include * #include * ... * struct addrinfo *addr; @@ -46,4 +52,116 @@ struct addrinfo *net_client_lookup(const char *hostname, * freeaddrinfo(addr); */ int net_connect(const struct addrinfo *addrinfo); + +/** + * net_connect_async - initiate connect to a server + * @addrinfo: linked list struct addrinfo (usually from net_client_lookup). + * @pfds: array of two struct pollfd. + * + * This begins connecting to a server described by @addrinfo, + * and places the one or two file descriptors into pfds[0] and pfds[1]. + * It returns a valid file descriptor if connect() returned immediately. + * + * Otherwise it returns -1 and sets errno, most likely EINPROGRESS. + * In this case, poll() on pfds and call net_connect_complete(). + * + * Example: + * struct pollfd pfds[2]; + * ... + * fd = net_connect_async(addr, pfds); + * if (fd < 0 && errno != EINPROGRESS) + * err(1, "Failed to connect to ccan.ozlabs.org"); + */ +int net_connect_async(const struct addrinfo *addrinfo, struct pollfd *pfds); + +/** + * net_connect_complete - complete net_connect_async call. + * @pfds: array of two struct pollfd handed to net_connect_async. + * + * When poll() reports some activity, this determines whether a connection + * has completed. If so, it cleans up and returns the connected fd. + * Otherwise, it returns -1, and sets errno (usually EINPROGRESS). + * + * Example: + * // After net_connect_async. + * while (fd < 0 && errno == EINPROGRESS) { + * // Wait for activity... + * poll(pfds, 2, -1); + * fd = net_connect_complete(pfds); + * } + * if (fd < 0) + * err(1, "connecting"); + * printf("Connected on fd %i!\n", fd); + */ +int net_connect_complete(struct pollfd *pfds); + +/** + * net_connect_abort - abort a net_connect_async call. + * @pfds: array of two struct pollfd handed to net_connect_async. + * + * Closes the file descriptors. + * + * Example: + * // After net_connect_async. + * if (poll(pfds, 2, 1000) == 0) { // Timeout. + * net_connect_abort(pfds); + * fd = -1; + * } else { + * fd = net_connect_complete(pfds); + * if (fd < 0) + * err(1, "connecting"); + * } + */ +void net_connect_abort(struct pollfd *pfds); + +/** + * net_server_lookup - look up a service name to bind to. + * @service: the service to look up + * @family: Usually AF_UNSPEC, otherwise AF_INET or AF_INET6. + * @socktype: SOCK_DGRAM or SOCK_STREAM. + * + * This will do a synchronous lookup of a given name, returning a linked list + * of results, or NULL on error. You should use freeaddrinfo() to free it. + * + * Example: + * #include + * #include + * #include + * #include + * #include + * ... + * struct addrinfo *addr; + * + * // Get address(es) to bind for our service. + * addr = net_server_lookup("8888", AF_UNSPEC, SOCK_STREAM); + * if (!addr) + * errx(1, "Failed to look up 8888 to bind to"); + */ +struct addrinfo *net_server_lookup(const char *service, + int family, + int socktype); + +/** + * net_bind - create listening socket(s) + * @addrinfo: the address(es) to bind to. + * @fds: array of two fds. + * + * This will create one (or if necessary) two sockets, mark them + * SO_REUSEADDR, bind them to the given address(es), and make them + * listen() (if the socket type is SOCK_STREAM or SOCK_SEQPACKET). + * + * Returns -1 (and sets errno) on error, or 1 or 2 depending on how many + * @fds are valid. + * + * Example: + * int fds[2], i, num_fds; + * + * num_fds = net_bind(addr, fds); + * if (num_fds < 0) + * err(1, "Failed to listen on port 8888"); + * + * for (i = 0; i < num_fds; i++) + * printf(" Got fd %u/%u: %i\n", i, num_fds, fds[i]); + */ +int net_bind(const struct addrinfo *addrinfo, int fds[2]); #endif /* CCAN_NET_H */