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
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
/*
* (c) Copyright 1990, Kim Fabricius Storm. All rights reserved.
* Copyright (c) 1996-2005 Michael T Pins. All rights reserved.
*
* "generic" gethostname() emulation:
*
* Possibilities are used in following order:
*
* HAVE_GETHOSTNAME -- use gethostname()
* HAVE_UNAME -- use sysV uname().nodename
* HOSTNAME_FILE "/.../..." -- read hostname from file
* HOSTNAME_WHOAMI -- use sysname from whoami.h
* HOSTNAME "host" -- hard-coded hostname
* You lose!
*/
#include <unistd.h>
#include <string.h>
#include "config.h"
#undef DONE
#ifdef HAVE_GETHOSTNAME
/*
* Easy -- we already got it
*/
void
nn_gethostname(char *name, int length)
{
gethostname(name, length);
}
#define DONE
#endif
#ifndef DONE
#ifdef HAVE_UNAME
/*
* System V uname() is available. Use nodename field.
*/
#include <sys/utsname.h>
void
nn_gethostname(char *name, int length)
{
struct utsname un;
uname(&un);
strncpy(name, un.nodename, length);
}
#define DONE
#endif
#endif
#ifndef DONE
#ifdef HOSTNAME_FILE
/*
* Hostname is available in a file.
* The name of the file is defined in HOSTNAME_FILE.
* This is not intended to fail (or exit would have been via nn_exit)
*/
void
nn_gethostname(char *name, int length)
{
FILE *f;
register char *p;
f = fopen(HOSTNAME_FILE, "r"); /* Generic code -- don't use
* open_file */
if (f == NULL)
goto err;
if (fgets(name, length, f) == NULL)
goto err;
if ((p = strchr(name, NL)) != NULL)
*p = NUL;
fclose(f);
return;
err:
fprintf(stderr, "HOSTNAME NOT FOUND IN %s\n", HOSTNAME_FILE);
exit(77);
}
#define DONE
#endif
#endif
#ifndef DONE
#ifdef HOSTNAME_WHOAMI
/*
* Hostname is found in whoami.h
*/
void
nn_gethostname(char *name, int length)
{
FILE *f;
char buf[512];
register char *p, *q;
f = fopen("/usr/include/whoami.h", "r");
if (f == NULL)
goto err;
while (fgets(buf, 512, f) != NULL) {
if (buf[0] != '#')
continue;
if ((p = strchr(buf, '"')) == NULL)
continue;
*p++ = NUL;
if (strncmp(buf, "#define sysname", 15))
continue;
if ((q = strchr(p, '"')) == NULL)
break;
*q = NUL;
strncpy(name, p, length);
return;
}
err:
fprintf(stderr, "HOSTNAME (sysname) NOT DEFINED IN whoami.h\n");
exit(77);
}
#define DONE
#endif
#endif
#ifndef DONE
#ifdef HOSTNAME
void
nn_gethostname(char *name, int length)
{
strncpy(name, HOSTNAME, length);
}
#define DONE
#endif
#endif
#ifndef DONE
YOU LOSE ON GETHOSTNAME-- DEFINE HOSTNAME IN CONFIG.H
#endif
|
