1 /* vi: set sw=4 ts=4: */
2 /*
3  * Generic non-forking server infrastructure.
4  * Intended to make writing telnetd-type servers easier.
5  *
6  * Copyright (C) 2007 Denys Vlasenko
7  *
8  * Licensed under GPLv2, see file LICENSE in this source tree.
9  */
10 
11 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
12 
13 /* opaque structure */
14 struct isrv_state_t;
15 typedef struct isrv_state_t isrv_state_t;
16 
17 /* callbacks */
18 void isrv_want_rd(isrv_state_t *state, int fd);
19 void isrv_want_wr(isrv_state_t *state, int fd);
20 void isrv_dont_want_rd(isrv_state_t *state, int fd);
21 void isrv_dont_want_wr(isrv_state_t *state, int fd);
22 int isrv_register_fd(isrv_state_t *state, int peer, int fd);
23 void isrv_close_fd(isrv_state_t *state, int fd);
24 int isrv_register_peer(isrv_state_t *state, void *param);
25 
26 /* Driver:
27  *
28  * Select on listen_fd for <linger_timeout> (or forever if 0).
29  *
30  * If we time out and we have no peers, exit.
31  * If we have peers, call do_timeout(peer_param),
32  * if it returns !0, peer is removed.
33  *
34  * If listen_fd is active, accept new connection ("peer"),
35  * call new_peer() on it, and if it returns 0,
36  * add it to fds to select on.
37  * Now, select will wait for <timeout>, not <linger_timeout>
38  * (as long as we have more than zero peers).
39  *
40  * If a peer's fd is active, we call do_rd() on it if read
41  * bit was set, and then do_wr() if write bit was also set.
42  * If either returns !0, peer is removed.
43  * Reaching this place also resets timeout counter for this peer.
44  *
45  * Note that peer must indicate that he wants to be selected
46  * for read and/or write using isrv_want_rd()/isrv_want_wr()
47  * [can be called in new_peer() or in do_rd()/do_wr()].
48  * If it never wants to be selected for write, do_wr()
49  * will never be called (can be NULL).
50  */
51 void isrv_run(
52 	int listen_fd,
53 	int (*new_peer)(isrv_state_t *state, int fd),
54 	int (*do_rd)(int fd, void **),
55 	int (*do_wr)(int fd, void **),
56 	int (*do_timeout)(void **),
57 	int timeout,
58 	int linger_timeout
59 );
60 
61 POP_SAVED_FUNCTION_VISIBILITY
62