chiark / gitweb /
New interface for messing with preconnected sockets.
[mLib] / conn.c
CommitLineData
97f65b00 1/* -*-c-*-
2 *
f128ce74 3 * $Id: conn.c,v 1.8 2003/10/12 14:47:10 mdw Exp $
97f65b00 4 *
5 * Nonblocking connect handling
6 *
a3ddb778 7 * (c) 1999 Straylight/Edgeware
97f65b00 8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30/*----- Revision history --------------------------------------------------*
31 *
32 * $Log: conn.c,v $
f128ce74 33 * Revision 1.8 2003/10/12 14:47:10 mdw
34 * New interface for messing with preconnected sockets.
35 *
c9bb3f9e 36 * Revision 1.7 2002/01/13 13:28:44 mdw
37 * Rearrange @conn_init@ to be a bit more comprehensible.
38 *
ff34c6e7 39 * Revision 1.6 2001/06/22 19:35:20 mdw
40 * Interface change to @conn_init@ -- return error rather than calling the
41 * function. This reduces the number of different environments the
42 * callback has to cope with, and the old behaviour is easily simulatable
43 * with the new, while simulating the new behaviour was awkward and
44 * painful.
45 *
d320826d 46 * Revision 1.5 2000/10/08 11:17:26 mdw
47 * (conn_connect): Change sizes to be @size_t@.
48 *
89f167ab 49 * Revision 1.4 1999/07/26 23:21:02 mdw
50 * Bug fix: remove the selector before doing the callback, in case client
51 * adds a writer for the connected socket.
52 *
5feb52af 53 * Revision 1.3 1999/05/23 12:12:37 mdw
54 * Interface change to make the `conn' selector useful for generic stream
55 * sockets rather than just IPv4 ones.
56 *
a3ddb778 57 * Revision 1.2 1999/05/15 10:33:32 mdw
58 * Fix copyright notices.
59 *
97f65b00 60 * Revision 1.1 1999/05/14 21:01:14 mdw
61 * Integrated `select' handling bits from the background resolver project.
62 *
63 */
64
65/*----- Header files ------------------------------------------------------*/
66
67#include <errno.h>
5feb52af 68#include <limits.h>
97f65b00 69#include <stdio.h>
70#include <stdlib.h>
71#include <string.h>
72
73#include <sys/types.h>
97f65b00 74#include <sys/socket.h>
97f65b00 75
76#include <unistd.h>
77#include <fcntl.h>
78
79#include "conn.h"
80#include "sel.h"
81
82/*----- Main code ---------------------------------------------------------*/
83
84/* --- @conn_connect@ --- *
85 *
86 * Arguments: @int fd@ = file descriptor to try to connect
87 * @unsigned mode@ = what we can do to the file
88 * @void *p@ = pointer to connection context
89 *
90 * Returns: ---
91 *
92 * Use: Handles select results for pending connections.
93 */
94
95static void conn_connect(int fd, unsigned mode, void *p)
96{
5feb52af 97#ifndef PATH_MAX
98# define PATH_MAX 1024
99#endif
100
97f65b00 101 conn *c = p;
5feb52af 102 char buf[PATH_MAX + 8]; /* Big enough */
d320826d 103 size_t sinsz;
97f65b00 104
5feb52af 105 sinsz = sizeof(buf);
89f167ab 106 sel_rmfile(&c->writer);
5feb52af 107 if (getpeername(fd, (struct sockaddr *)buf, &sinsz) < 0) {
97f65b00 108 int err;
d320826d 109 size_t errsz = sizeof(err);
97f65b00 110 if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errsz) == 0)
111 errno = err;
97f65b00 112 close(fd);
89f167ab 113 c->func(-1, c->p);
97f65b00 114 } else
115 c->func(fd, c->p);
97f65b00 116}
117
f128ce74 118/* --- @conn_fd@ --- *
119 *
120 * Arguments: @conn *c@ = pointer to connection block
121 * @sel_state *s@ = pointer to select state to attach to
122 * @int fd@ = file descriptor of socket
123 * @void (*func)(int fd, void *p) = handler function
124 * @void *p@ = argument for the handler function
125 *
126 * Returns: ---
127 *
128 * Use: Sets up a nonblocking connect job. The socket should have a
129 * connect pending for it already.
130 */
131
132void conn_fd(conn *c, sel_state *s, int fd,
133 void (*func)(int /*fd*/, void */*p*/),
134 void *p)
135{
136 c->func = func;
137 c->p = p;
138 sel_initfile(s, &c->writer, fd, SEL_WRITE, conn_connect, c);
139 sel_addfile(&c->writer);
140}
141
97f65b00 142/* --- @conn_init@ --- *
143 *
144 * Arguments: @conn *c@ = pointer to connection block
145 * @sel_state *s@ = pointer to select state to attach to
5feb52af 146 * @int fd@ = file descriptor of socket to connect
147 * @struct sockaddr *dst@ = destination address
148 * @int dsz@ = size of destination address
97f65b00 149 * @void (*func)(int fd, void *p) = handler function
150 * @void *p@ = argument for the handler function
151 *
ff34c6e7 152 * Returns: Zero on success, nonzero on failure.
97f65b00 153 *
5feb52af 154 * Use: Sets up a nonblocking connect job. The socket should already
155 * be bound if you care about that sort of thing. When the
156 * connection completes, the handler function is called with the
157 * connected socket as an argument. If the connect fails rather
158 * than completes, the socket is closed, and the handler is
159 * informed of this by being passed a negative file descriptor.
160 * In either case, the select job is then removed.
97f65b00 161 */
162
ff34c6e7 163int conn_init(conn *c, sel_state *s, int fd,
164 struct sockaddr *dst, int dsz,
165 void (*func)(int /*fd*/, void */*p*/),
166 void *p)
97f65b00 167{
5feb52af 168 int f;
97f65b00 169
f128ce74 170 if ((f = fcntl(fd, F_GETFL)) < 0 || fcntl(fd, F_SETFL, f | O_NONBLOCK)) {
171 close(fd);
172 return (-1);
173 }
97f65b00 174
c9bb3f9e 175 if (!connect(fd, dst, dsz))
176 func(fd, p);
177 else if (errno != EINPROGRESS)
178 goto fail;
f128ce74 179 else
180 conn_fd(c, s, fd, func, p);
ff34c6e7 181 return (0);
97f65b00 182}
183
184/* --- @conn_kill@ --- *
185 *
186 * Arguments: @conn *c@ = pointer to connection to dispose of
187 *
188 * Returns: ---
189 *
190 * Use: Disposes of a connection when it's not wanted any more.
191 */
192
193void conn_kill(conn *c)
194{
195 if (c->writer.fd != -1) {
196 close(c->writer.fd);
197 sel_rmfile(&c->writer);
198 c->writer.fd = -1;
199 }
200}
201
202/*----- That's all, folks -------------------------------------------------*/