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/* Licensed under BSD-MIT - see LICENSE file for details */
#ifndef CCAN_NET_H
#define CCAN_NET_H
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <stdbool.h>
struct pollfd;
/**
* net_client_lookup - look up a network name to connect to.
* @hostname: the name to look up
* @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 <stdio.h>
* #include <poll.h>
* #include <err.h>
* ...
* struct addrinfo *addr;
*
* // Get a TCP connection to ccan.ozlabs.org daytime port.
* addr = net_client_lookup("ccan.ozlabs.org", "daytime",
* AF_UNSPEC, SOCK_STREAM);
* if (!addr)
* errx(1, "Failed to look up daytime at ccan.ozlabs.org");
*/
struct addrinfo *net_client_lookup(const char *hostname,
const char *service,
int family,
int socktype);
/**
* net_connect - connect to a server
* @addrinfo: linked list struct addrinfo (usually from net_client_lookup).
*
* This synchronously connects to a server described by @addrinfo, or returns
* -1 on error (and sets errno).
*
* Example:
* int fd;
* ...
* fd = net_connect(addr);
* if (fd < 0)
* err(1, "Failed to connect to ccan.ozlabs.org");
* 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 <stdio.h>
* #include <err.h>
* ...
* 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 */
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