1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#include "bsd.h"
#if defined(TALK_43) || defined(TALK_42)
# include <stdio.h>
# include <string.h>
# include "talk_ctl.h"
# include <sys/param.h>
# include <netdb.h>
extern CTL_MSG msg;
struct hostent *gethostbyname();
struct servent *getservbyname();
static char hostname[MAXHOSTNAMELEN];
char *my_machine_name;
/*
* Determine the local user and machine
*/
get_local_name(my_name)
char *my_name;
{
struct hostent *hp;
struct servent *sp;
/* Load these useful values into the standard message header */
msg.id_num = 0;
(void) strncpy(msg.l_name, my_name, NAME_SIZE);
msg.l_name[NAME_SIZE - 1] = '\0';
msg.r_tty[0] = '\0';
msg.pid = getpid();
# ifdef TALK_43
msg.vers = TALK_VERSION;
msg.addr.sa_family = htons(AF_INET);
msg.ctl_addr.sa_family = htons(AF_INET);
# else
msg.addr.sin_family = htons(AF_INET);
msg.ctl_addr.sin_family = htons(AF_INET);
# endif
(void) gethostname(hostname, sizeof (hostname));
my_machine_name = hostname;
/* look up the address of the local host */
hp = gethostbyname(my_machine_name);
if (hp == (struct hostent *) 0) {
printf("This machine doesn't exist. Boy, am I confused!\n");
exit(-1);
}
memcpy(&my_machine_addr, hp->h_addr, hp->h_length);
/* find the daemon portal */
# ifdef TALK_43
sp = getservbyname("ntalk", "udp");
# else
sp = getservbyname("talk", "udp");
# endif
if (sp == 0) {
# ifdef LOG
syslog(LOG_ERR, "This machine doesn't support talk");
# else
perror("This machine doesn't support talk");
# endif
exit(-1);
}
daemon_port = sp->s_port;
}
/*
* Determine the remote user and machine
*/
get_remote_name(his_address)
char *his_address;
{
char *his_name;
char *his_machine_name;
char *ptr;
struct hostent *hp;
/* check for, and strip out, the machine name of the target */
for (ptr = his_address; *ptr != '\0' && *ptr != '@' && *ptr != ':'
&& *ptr != '!' && *ptr != '.'; ptr++)
continue;
if (*ptr == '\0') {
/* this is a local to local talk */
his_name = his_address;
his_machine_name = my_machine_name;
} else {
if (*ptr == '@') {
/* user@host */
his_name = his_address;
his_machine_name = ptr + 1;
} else {
/* host.user or host!user or host:user */
his_name = ptr + 1;
his_machine_name = his_address;
}
*ptr = '\0';
}
/* Load these useful values into the standard message header */
(void) strncpy(msg.r_name, his_name, NAME_SIZE);
msg.r_name[NAME_SIZE - 1] = '\0';
/* if he is on the same machine, then simply copy */
if (bcmp((char *) &his_machine_name, (char *) &my_machine_name,
sizeof(his_machine_name)) == 0)
memcpy(&his_machine_addr, &my_machine_addr,
sizeof(his_machine_name));
else {
/* look up the address of the recipient's machine */
hp = gethostbyname(his_machine_name);
if (hp == (struct hostent *) 0)
return 0; /* unknown host */
memcpy(&his_machine_addr, hp->h_addr, hp->h_length);
}
return 1;
}
#endif
|
