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1.1 root 1: /*
2: * Copyright (c) 1983 Regents of the University of California.
3: * All rights reserved. The Berkeley software License Agreement
4: * specifies the terms and conditions for redistribution.
5: */
6:
7: #ifndef lint
8: static char sccsid[] = "@(#)announce.c 5.3 (Berkeley) 3/13/86";
9: #endif not lint
10:
11: #include <sys/types.h>
12: #include <sys/stat.h>
13: #include <sgtty.h>
14: #include <sys/ioctl.h>
15: #include <sys/time.h>
16: #include <stdio.h>
17: #include <sys/wait.h>
18: #include <errno.h>
19: #include <syslog.h>
20:
21: #include <protocols/talkd.h>
22:
23: extern int errno;
24: extern char hostname[];
25:
26: /*
27: * Announce an invitation to talk.
28: *
29: * Because the tty driver insists on attaching a terminal-less
30: * process to any terminal that it writes on, we must fork a child
31: * to protect ourselves
32: */
33: announce(request, remote_machine)
34: CTL_MSG *request;
35: char *remote_machine;
36: {
37: int pid, val, status;
38:
39: if (pid = fork()) {
40: /* we are the parent, so wait for the child */
41: if (pid == -1) /* the fork failed */
42: return (FAILED);
43: do {
44: val = wait(&status);
45: if (val == -1) {
46: if (errno == EINTR)
47: continue;
48: /* shouldn't happen */
49: syslog(LOG_WARNING, "announce: wait: %m");
50: return (FAILED);
51: }
52: } while (val != pid);
53: if (status&0377 > 0) /* we were killed by some signal */
54: return (FAILED);
55: /* Get the second byte, this is the exit/return code */
56: return ((status >> 8) & 0377);
57: }
58: /* we are the child, go and do it */
59: _exit(announce_proc(request, remote_machine));
60: }
61:
62: /*
63: * See if the user is accepting messages. If so, announce that
64: * a talk is requested.
65: */
66: announce_proc(request, remote_machine)
67: CTL_MSG *request;
68: char *remote_machine;
69: {
70: int pid, status;
71: char full_tty[32];
72: FILE *tf;
73: struct stat stbuf;
74:
75: sprintf(full_tty, "/dev/%s", request->r_tty);
76: if (access(full_tty, 0) != 0)
77: return (FAILED);
78: if ((tf = fopen(full_tty, "w")) == NULL)
79: return (PERMISSION_DENIED);
80: /*
81: * On first tty open, the server will have
82: * it's pgrp set, so disconnect us from the
83: * tty before we catch a signal.
84: */
85: ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0);
86: if (fstat(fileno(tf), &stbuf) < 0)
87: return (PERMISSION_DENIED);
88: if ((stbuf.st_mode&020) == 0)
89: return (PERMISSION_DENIED);
90: print_mesg(tf, request, remote_machine);
91: fclose(tf);
92: return (SUCCESS);
93: }
94:
95: #define max(a,b) ( (a) > (b) ? (a) : (b) )
96: #define N_LINES 5
97: #define N_CHARS 120
98:
99: /*
100: * Build a block of characters containing the message.
101: * It is sent blank filled and in a single block to
102: * try to keep the message in one piece if the recipient
103: * in in vi at the time
104: */
105: print_mesg(tf, request, remote_machine)
106: FILE *tf;
107: CTL_MSG *request;
108: char *remote_machine;
109: {
110: struct timeval clock;
111: struct timezone zone;
112: struct tm *localtime();
113: struct tm *localclock;
114: char line_buf[N_LINES][N_CHARS];
115: int sizes[N_LINES];
116: char big_buf[N_LINES*N_CHARS];
117: char *bptr, *lptr;
118: int i, j, max_size;
119:
120: i = 0;
121: max_size = 0;
122: gettimeofday(&clock, &zone);
123: localclock = localtime( &clock.tv_sec );
124: sprintf(line_buf[i], " ");
125: sizes[i] = strlen(line_buf[i]);
126: max_size = max(max_size, sizes[i]);
127: i++;
128: sprintf(line_buf[i], "Message from Talk_Daemon@%s at %d:%02d ...",
129: hostname, localclock->tm_hour , localclock->tm_min );
130: sizes[i] = strlen(line_buf[i]);
131: max_size = max(max_size, sizes[i]);
132: i++;
133: sprintf(line_buf[i], "talk: connection requested by %s@%s.",
134: request->l_name, remote_machine);
135: sizes[i] = strlen(line_buf[i]);
136: max_size = max(max_size, sizes[i]);
137: i++;
138: sprintf(line_buf[i], "talk: respond with: talk %s@%s",
139: request->l_name, remote_machine);
140: sizes[i] = strlen(line_buf[i]);
141: max_size = max(max_size, sizes[i]);
142: i++;
143: sprintf(line_buf[i], " ");
144: sizes[i] = strlen(line_buf[i]);
145: max_size = max(max_size, sizes[i]);
146: i++;
147: bptr = big_buf;
148: *bptr++ = ''; /* send something to wake them up */
149: *bptr++ = '\r'; /* add a \r in case of raw mode */
150: *bptr++ = '\n';
151: for (i = 0; i < N_LINES; i++) {
152: /* copy the line into the big buffer */
153: lptr = line_buf[i];
154: while (*lptr != '\0')
155: *(bptr++) = *(lptr++);
156: /* pad out the rest of the lines with blanks */
157: for (j = sizes[i]; j < max_size + 2; j++)
158: *(bptr++) = ' ';
159: *(bptr++) = '\r'; /* add a \r in case of raw mode */
160: *(bptr++) = '\n';
161: }
162: *bptr = '\0';
163: fprintf(tf, big_buf);
164: fflush(tf);
165: ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0);
166: }
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