masqmail

view src/listen.c @ 394:c8e3d1a79313

Refactoring in conf.c: read_rval().
author markus schnalke <meillo@marmaro.de>
date Sat, 18 Feb 2012 19:32:40 +0100
parents a2909de1818b
children 180a7f6a9383
line source
1 /*
2 ** MasqMail
3 ** Copyright (C) 1999/2000 Oliver Kurth
4 **
5 ** This program is free software; you can redistribute it and/or modify
6 ** it under the terms of the GNU General Public License as published by
7 ** the Free Software Foundation; either version 2 of the License, or
8 ** (at your option) any later version.
9 **
10 ** This program is distributed in the hope that it will be useful,
11 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
12 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 ** GNU General Public License for more details.
14 **
15 ** You should have received a copy of the GNU General Public License
16 ** along with this program; if not, write to the Free Software
17 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 */
20 #include <sys/wait.h>
21 #include <sys/types.h>
23 #include "masqmail.h"
25 static int volatile sighup_seen = 0;
27 static void
28 sighup_handler(int sig)
29 {
30 sighup_seen = 1;
31 signal(SIGHUP, sighup_handler);
32 }
34 static void
35 sigchld_handler(int sig)
36 {
37 pid_t pid;
38 int status;
40 pid = waitpid(0, &status, 0);
41 if (pid > 0) {
42 if (WEXITSTATUS(status) != 0) {
43 logwrite(LOG_WARNING, "process %d exited with %d\n",
44 pid, WEXITSTATUS(status));
45 }
46 if (WIFSIGNALED(status)) {
47 logwrite(LOG_WARNING, "process %d got signal: %d\n",
48 pid, WTERMSIG(status));
49 }
50 }
51 signal(SIGCHLD, sigchld_handler);
52 }
54 void
55 accept_connect(int listen_sock, int sock, struct sockaddr_in *sock_addr)
56 {
57 pid_t pid;
58 int dup_sock = dup(sock);
59 FILE *out, *in;
60 gchar *rem_host;
61 gchar *ident = NULL;
63 rem_host = g_strdup(inet_ntoa(sock_addr->sin_addr));
64 logwrite(LOG_NOTICE, "connect from host %s, port %hu\n",
65 rem_host, ntohs(sock_addr->sin_port));
67 /* start child for connection: */
68 signal(SIGCHLD, sigchld_handler);
69 pid = fork();
70 if (pid < 0) {
71 logwrite(LOG_WARNING, "could not fork for incoming smtp "
72 "connection: %s\n", strerror(errno));
73 } else if (pid == 0) {
74 /* child */
75 close(listen_sock);
76 out = fdopen(sock, "w");
77 in = fdopen(dup_sock, "r");
78 smtp_in(in, out, rem_host, ident);
79 _exit(0);
80 }
82 close(sock);
83 close(dup_sock);
84 }
86 void
87 listen_port(GList *iface_list, gint qival, char *argv[])
88 {
89 int i;
90 fd_set active_fd_set, read_fd_set;
91 struct timeval tm;
92 time_t time_before, time_now;
93 struct sockaddr_in clientname;
94 size_t size;
95 GList *node, *node_next;
96 int sel_ret;
98 /* Create the sockets and set them up to accept connections. */
99 FD_ZERO(&active_fd_set);
100 for (node = g_list_first(iface_list); node; node = node_next) {
101 interface *iface = (interface *) (node->data);
102 int sock;
104 node_next = g_list_next(node);
105 if ((sock = make_server_socket(iface)) < 0) {
106 iface_list = g_list_remove_link(iface_list, node);
107 g_list_free_1(node);
108 continue;
109 }
110 if (listen(sock, 1) < 0) {
111 logwrite(LOG_ALERT, "listen: (terminating): %s\n",
112 strerror(errno));
113 exit(1);
114 }
115 logwrite(LOG_NOTICE, "listening on interface %s:%d\n",
116 iface->address, iface->port);
117 DEBUG(5) debugf("sock = %d\n", sock);
118 FD_SET(sock, &active_fd_set);
119 }
121 /* setup handler for HUP signal: */
122 signal(SIGHUP, sighup_handler);
123 signal(SIGCHLD, sigchld_handler);
125 /* now that we have our socket(s), we can give up root privileges */
126 if (!conf.run_as_user) {
127 set_euidgid(conf.mail_uid, conf.mail_gid, NULL, NULL);
128 }
130 /* sel_ret = 0; */
131 time(&time_before);
132 time_before -= qival;
133 sel_ret = -1;
135 while (1) {
137 /*
138 ** if we were interrupted by an incoming connection (or a
139 ** signal) we have to recalculate the time until the next
140 ** queue run should occur. select may put a value into tm,
141 ** but doc for select() says we should not use it.
142 */
143 if (qival > 0) {
144 time(&time_now);
145 if (!sel_ret) {
146 /* either just starting or after a queue run */
147 tm.tv_sec = qival;
148 tm.tv_usec = 0;
149 time_before = time_now;
150 } else {
151 tm.tv_sec = qival - (time_now - time_before);
152 tm.tv_usec = 0;
154 /* race condition, unlikely (but possible): */
155 if (tm.tv_sec < 0) {
156 tm.tv_sec = 0;
157 }
158 }
159 }
160 /*
161 ** Block until input arrives on one or more active sockets,
162 ** or signal arrives, or queuing interval time elapsed
163 ** (if qival > 0)
164 */
165 read_fd_set = active_fd_set;
166 if ((sel_ret = select(FD_SETSIZE, &read_fd_set, NULL, NULL,
167 qival > 0 ? &tm : NULL)) < 0) {
168 if (errno != EINTR) {
169 logwrite(LOG_ALERT, "select: (terminating): "
170 "%s\n", strerror(errno));
171 exit(1);
172 } else if (sighup_seen) {
173 logwrite(LOG_NOTICE, "HUP signal received. "
174 "Restarting daemon\n");
176 for (i = 0; i < FD_SETSIZE; i++)
177 if (FD_ISSET(i, &active_fd_set))
178 close(i);
180 execv(argv[0], &(argv[0]));
181 logwrite(LOG_ALERT, "restarting failed: %s\n",
182 strerror(errno));
183 exit(1);
184 }
185 } else if (sel_ret > 0) {
186 for (i = 0; i < FD_SETSIZE; i++) {
187 int sock = i;
188 int new;
190 if (!FD_ISSET(i, &read_fd_set)) {
191 continue;
192 }
193 size = sizeof(clientname);
194 new = accept(sock, (struct sockaddr *)
195 &clientname, &size);
196 if (new < 0) {
197 logwrite(LOG_ALERT, "accept: (ignoring): %s\n", strerror(errno));
198 } else {
199 accept_connect(sock, new,
200 &clientname);
201 }
202 }
203 } else {
204 /*
205 ** If select returns 0, the interval time has elapsed.
206 ** We start a new queue runner process
207 */
208 int pid;
209 signal(SIGCHLD, sigchld_handler);
210 if ((pid = fork()) == 0) {
211 queue_run();
213 _exit(0);
214 } else if (pid < 0) {
215 logwrite(LOG_ALERT, "could not fork for "
216 "queue run");
217 }
218 }
219 }
220 }