1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30 # include <stdarg.h>
31 # include <limits.h>
32 # include <sys/types.h>
33 # include <poll.h>
34 # include <stropts.h>
35 # include <unistd.h>
36 #include <syslog.h>
37
38 # include "lpsched.h"
39
40 #define TURN_OFF(X,F) (void)Fcntl(X, F_SETFL, (Fcntl(X, F_GETFL, 0) & ~(F)))
41
42
43 static void conn_shutdown();
44
45 extern int Filter_Status;
46 extern void dispatch();
47 extern int Waitrequest;
48 void shutdown_messages();
49 static char *Message;
50 static int MaxClients = 0,
51 do_msg();
52 extern int Reserve_Fds;
53 extern int Shutdown;
54
55 MESG *Net_md;
56
57 /*
58 ** take_message() - WAIT FOR INTERRUPT OR ONE MESSAGE FROM USER PROCESS
59 */
60
take_message(void)61 void take_message(void)
62 {
63 int bytes;
64 int i;
65 MESG * md;
66
67 for (EVER) { /* not really forever...returns are in the loop */
68 if ((md = mlisten()) == NULL)
69 switch(errno) {
70 case EAGAIN:
71 case EINTR:
72 return;
73
74 case ENOMEM:
75 mallocfail();
76 /* NOTREACHED */
77
78 default:
79 fail ("Unexpected streams error in mlisten (%s).\n" , PERROR);
80 }
81
82 /*
83 * Check for a dropped connection to a child.
84 * Normally a child should tell us that it is dying
85 * (with S_SHUTDOWN or S_SEND_CHILD), but it may have
86 * died a fast death. We'll simulate the message we
87 * wanted to get so we can use the same code to clean up.
88 */
89 if ((md->event & POLLHUP) && !(md->event & POLLIN) ||
90 (md->event & (POLLERR|POLLNVAL))) {
91 switch (md->type) {
92
93 case MD_CHILD:
94 /*
95 * If the message descriptor is found in the
96 * exec table, it must be an interface pgm,
97 * notification, etc. Otherwise, it must be
98 * a network child.
99 */
100 for (i = 0; Exec_Table[i] != NULL; i++)
101 if (Exec_Table[i]->md == md)
102 break;
103
104 if (Exec_Table[i] != NULL) {
105 (void) putmessage(Message, S_CHILD_DONE,
106 Exec_Table[i]->key, 0, 0);
107 } else {
108 (void) putmessage(Message, S_SHUTDOWN, 1);
109 }
110 bytes = 1;
111 break;
112
113 default:
114 bytes = -1;
115 break;
116
117 }
118
119 } else {
120 if (md->readfd == -1) { /* something happened to the readfd */
121 syslog(LOG_DEBUG, "take_message: readfd is -1");
122 return;
123 }
124 bytes = mread(md, Message, MSGMAX);
125 }
126
127 switch (bytes) {
128 case -1:
129 if (errno == EINTR)
130 return;
131 else
132 fail ("Unexpected streams error (%s).\n" , PERROR);
133 break;
134
135 case 0:
136 break;
137
138 default:
139 if (do_msg(md))
140 return;
141 break;
142 }
143 }
144 }
145
146 /*
147 ** do_msg() - HANDLE AN INCOMING MESSAGE
148 */
149
150 static int
do_msg(MESG * md)151 do_msg(MESG *md)
152 {
153 int type = mtype(Message);
154
155 if (type != S_GOODBYE) {
156 md->wait = 0;
157 dispatch (type, Message, md);
158 /*
159 * The message may have caused the need to
160 * schedule something, so go back and check.
161 */
162 return(1);
163 }
164 return(0);
165 }
166
167 /*
168 ** calculate_nopen() - DETERMINE # FILE DESCRIPTORS AVAILABLE FOR QUEUES
169 */
170
171 static void
calculate_nopen(void)172 calculate_nopen(void)
173 {
174 int fd, nopen;
175
176 /*
177 * How many file descriptorss are currently being used?
178 */
179 for (fd = nopen = 0; fd < OpenMax; fd++)
180 if (fcntl(fd, F_GETFL, 0) != -1)
181 nopen++;
182
183 /*
184 * How many file descriptors are available for use
185 * as open FIFOs? Leave one spare as a way to tell
186 * clients we don't have any to spare (hmmm....) and
187 * one for the incoming fifo.
188 */
189
190 MaxClients = OpenMax;
191 MaxClients -= nopen; /* current overhead */
192 MaxClients -= Reserve_Fds;
193 MaxClients -= 2; /* incoming FIFO and spare outgoing */
194 MaxClients--; /* the requests log */
195 MaxClients--; /* HPI routines and lpsched log */
196
197 return;
198 }
199
conn_shutdown()200 static void conn_shutdown ( )
201 {
202 if (!Shutdown) {
203 note ("The public connection \"%s\", has failed.\n", Lp_FIFO);
204 lpshut(1);
205 }
206 }
207
208 /*
209 ** init_messages() - INITIALIZE MAIN MESSAGE QUEUE
210 */
211
212 void
init_messages(void)213 init_messages(void)
214 {
215 char *cmd;
216 MESG * md;
217
218 (void) signal(SIGPIPE, SIG_IGN);
219
220 calculate_nopen ();
221
222 Message = (char *)Malloc(MSGMAX);
223
224 (void) Chmod(Lp_Tmp, 0711);
225
226 if ((md = mcreate(Lp_FIFO)) == NULL)
227 fail ("Can't create public message device (%s).\n", PERROR);
228 mon_discon(md, conn_shutdown);
229
230 if (mlisteninit(md) != 0)
231 if (errno == ENOMEM)
232 mallocfail();
233 else
234 fail ("Unexpected streams error (%s).\n" , PERROR);
235
236 (void) Chmod(Lp_FIFO, 0666);
237 return;
238 }
239
240
241 void
shutdown_messages(void)242 shutdown_messages(void)
243 {
244 MESG *md;
245
246 (void) Chmod(Lp_Tmp, 0700);
247 (void) Chmod(Lp_FIFO, 0600);
248 md = mlistenreset();
249 mdestroy(md);
250 }
251