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
31 #pragma ident "%Z%%M% %I% %E% SMI"
32
33 # include <stdarg.h>
34 # include <limits.h>
35 # include <sys/types.h>
36 # include <poll.h>
37 # include <stropts.h>
38 # include <unistd.h>
39 #include <syslog.h>
40
41 # include "lpsched.h"
42
43 #define TURN_OFF(X,F) (void)Fcntl(X, F_SETFL, (Fcntl(X, F_GETFL, 0) & ~(F)))
44
45
46 static void conn_shutdown();
47
48 extern int Filter_Status;
49 extern void dispatch();
50 extern int Waitrequest;
51 void shutdown_messages();
52 static char *Message;
53 static int MaxClients = 0,
54 do_msg();
55 extern int Reserve_Fds;
56 extern int Shutdown;
57
58 MESG *Net_md;
59
60 /*
61 ** take_message() - WAIT FOR INTERRUPT OR ONE MESSAGE FROM USER PROCESS
62 */
63
take_message(void)64 void take_message(void)
65 {
66 int bytes;
67 int i;
68 MESG * md;
69
70 for (EVER) { /* not really forever...returns are in the loop */
71 if ((md = mlisten()) == NULL)
72 switch(errno) {
73 case EAGAIN:
74 case EINTR:
75 return;
76
77 case ENOMEM:
78 mallocfail();
79 /* NOTREACHED */
80
81 default:
82 fail ("Unexpected streams error in mlisten (%s).\n" , PERROR);
83 }
84
85 /*
86 * Check for a dropped connection to a child.
87 * Normally a child should tell us that it is dying
88 * (with S_SHUTDOWN or S_SEND_CHILD), but it may have
89 * died a fast death. We'll simulate the message we
90 * wanted to get so we can use the same code to clean up.
91 */
92 if ((md->event & POLLHUP) && !(md->event & POLLIN) ||
93 (md->event & (POLLERR|POLLNVAL))) {
94 switch (md->type) {
95
96 case MD_CHILD:
97 /*
98 * If the message descriptor is found in the
99 * exec table, it must be an interface pgm,
100 * notification, etc. Otherwise, it must be
101 * a network child.
102 */
103 for (i = 0; Exec_Table[i] != NULL; i++)
104 if (Exec_Table[i]->md == md)
105 break;
106
107 if (Exec_Table[i] != NULL) {
108 (void) putmessage(Message, S_CHILD_DONE,
109 Exec_Table[i]->key, 0, 0);
110 } else {
111 (void) putmessage(Message, S_SHUTDOWN, 1);
112 }
113 bytes = 1;
114 break;
115
116 default:
117 bytes = -1;
118 break;
119
120 }
121
122 } else {
123 if (md->readfd == -1) { /* something happened to the readfd */
124 syslog(LOG_DEBUG, "take_message: readfd is -1");
125 return;
126 }
127 bytes = mread(md, Message, MSGMAX);
128 }
129
130 switch (bytes) {
131 case -1:
132 if (errno == EINTR)
133 return;
134 else
135 fail ("Unexpected streams error (%s).\n" , PERROR);
136 break;
137
138 case 0:
139 break;
140
141 default:
142 if (do_msg(md))
143 return;
144 break;
145 }
146 }
147 }
148
149 /*
150 ** do_msg() - HANDLE AN INCOMING MESSAGE
151 */
152
153 static int
do_msg(MESG * md)154 do_msg(MESG *md)
155 {
156 int type = mtype(Message);
157
158 if (type != S_GOODBYE) {
159 md->wait = 0;
160 dispatch (type, Message, md);
161 /*
162 * The message may have caused the need to
163 * schedule something, so go back and check.
164 */
165 return(1);
166 }
167 return(0);
168 }
169
170 /*
171 ** calculate_nopen() - DETERMINE # FILE DESCRIPTORS AVAILABLE FOR QUEUES
172 */
173
174 static void
calculate_nopen(void)175 calculate_nopen(void)
176 {
177 int fd, nopen;
178
179 /*
180 * How many file descriptorss are currently being used?
181 */
182 for (fd = nopen = 0; fd < OpenMax; fd++)
183 if (fcntl(fd, F_GETFL, 0) != -1)
184 nopen++;
185
186 /*
187 * How many file descriptors are available for use
188 * as open FIFOs? Leave one spare as a way to tell
189 * clients we don't have any to spare (hmmm....) and
190 * one for the incoming fifo.
191 */
192
193 MaxClients = OpenMax;
194 MaxClients -= nopen; /* current overhead */
195 MaxClients -= Reserve_Fds;
196 MaxClients -= 2; /* incoming FIFO and spare outgoing */
197 MaxClients--; /* the requests log */
198 MaxClients--; /* HPI routines and lpsched log */
199
200 return;
201 }
202
conn_shutdown()203 static void conn_shutdown ( )
204 {
205 if (!Shutdown) {
206 note ("The public connection \"%s\", has failed.\n", Lp_FIFO);
207 lpshut(1);
208 }
209 }
210
211 /*
212 ** init_messages() - INITIALIZE MAIN MESSAGE QUEUE
213 */
214
215 void
init_messages(void)216 init_messages(void)
217 {
218 char *cmd;
219 MESG * md;
220
221 (void) signal(SIGPIPE, SIG_IGN);
222
223 calculate_nopen ();
224
225 Message = (char *)Malloc(MSGMAX);
226
227 (void) Chmod(Lp_Tmp, 0711);
228
229 if ((md = mcreate(Lp_FIFO)) == NULL)
230 fail ("Can't create public message device (%s).\n", PERROR);
231 mon_discon(md, conn_shutdown);
232
233 if (mlisteninit(md) != 0)
234 if (errno == ENOMEM)
235 mallocfail();
236 else
237 fail ("Unexpected streams error (%s).\n" , PERROR);
238
239 (void) Chmod(Lp_FIFO, 0666);
240 return;
241 }
242
243
244 void
shutdown_messages(void)245 shutdown_messages(void)
246 {
247 MESG *md;
248
249 (void) Chmod(Lp_Tmp, 0700);
250 (void) Chmod(Lp_FIFO, 0600);
251 md = mlistenreset();
252 mdestroy(md);
253 }
254