1 /***
2 This file is part of avahi.
3
4 avahi is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 avahi is distributed in the hope that it will be useful, but WITHOUT
10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
12 Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with avahi; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
17 USA.
18 ***/
19
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23
24 #include <stdlib.h>
25 #include <assert.h>
26 #include <string.h>
27 #include <unistd.h>
28 #include <ctype.h>
29 #include <sys/utsname.h>
30 #include <stdio.h>
31
32 #include "avahi-common/avahi-malloc.h"
33
34 #include "log.h"
35 #include "domain-util.h"
36 #include "util.h"
37
strip_bad_chars(char * s)38 static void strip_bad_chars(char *s) {
39 char *p, *d;
40
41 s[strcspn(s, ".")] = 0;
42
43 for (p = s, d = s; *p; p++)
44 if ((*p >= 'a' && *p <= 'z') ||
45 (*p >= 'A' && *p <= 'Z') ||
46 (*p >= '0' && *p <= '9') ||
47 *p == '-')
48 *(d++) = *p;
49
50 *d = 0;
51 }
52
53 #ifdef __linux__
load_lsb_distrib_id(char * ret_s,size_t size)54 static int load_lsb_distrib_id(char *ret_s, size_t size) {
55 FILE *f;
56
57 assert(ret_s);
58 assert(size > 0);
59
60 if (!(f = fopen("/etc/lsb-release", "r")))
61 return -1;
62
63 while (!feof(f)) {
64 char ln[256], *p;
65
66 if (!fgets(ln, sizeof(ln), f))
67 break;
68
69 if (strncmp(ln, "DISTRIB_ID=", 11))
70 continue;
71
72 p = ln + 11;
73 p += strspn(p, "\"");
74 p[strcspn(p, "\"")] = 0;
75
76 snprintf(ret_s, size, "%s", p);
77
78 fclose(f);
79 return 0;
80 }
81
82 fclose(f);
83 return -1;
84 }
85 #endif
86
avahi_get_host_name(char * ret_s,size_t size)87 char *avahi_get_host_name(char *ret_s, size_t size) {
88 assert(ret_s);
89 assert(size > 0);
90
91 if (gethostname(ret_s, size) >= 0) {
92 ret_s[size-1] = 0;
93 strip_bad_chars(ret_s);
94 } else
95 *ret_s = 0;
96
97 if (strcmp(ret_s, "localhost") == 0 || strncmp(ret_s, "localhost.", 10) == 0) {
98 *ret_s = 0;
99 avahi_log_warn("System host name is set to 'localhost'. This is not a suitable mDNS host name, looking for alternatives.");
100 }
101
102 if (*ret_s == 0) {
103 /* No hostname was set, so let's take the OS name */
104
105 #ifdef __linux__
106
107 /* Try LSB distribution name first */
108 if (load_lsb_distrib_id(ret_s, size) >= 0) {
109 strip_bad_chars(ret_s);
110 avahi_strdown(ret_s);
111 }
112
113 if (*ret_s == 0)
114 #endif
115
116 {
117 /* Try uname() second */
118 struct utsname utsname;
119
120 if (uname(&utsname) >= 0) {
121 snprintf(ret_s, size, "%s", utsname.sysname);
122 strip_bad_chars(ret_s);
123 avahi_strdown(ret_s);
124 }
125
126 /* Give up */
127 if (*ret_s == 0)
128 snprintf(ret_s, size, "unnamed");
129 }
130 }
131
132 if (size >= AVAHI_LABEL_MAX)
133 ret_s[AVAHI_LABEL_MAX-1] = 0;
134
135 return ret_s;
136 }
137
avahi_get_host_name_strdup(void)138 char *avahi_get_host_name_strdup(void) {
139 char t[AVAHI_DOMAIN_NAME_MAX];
140
141 if (!(avahi_get_host_name(t, sizeof(t))))
142 return NULL;
143
144 return avahi_strdup(t);
145 }
146
avahi_binary_domain_cmp(const char * a,const char * b)147 int avahi_binary_domain_cmp(const char *a, const char *b) {
148 assert(a);
149 assert(b);
150
151 if (a == b)
152 return 0;
153
154 for (;;) {
155 char ca[AVAHI_LABEL_MAX], cb[AVAHI_LABEL_MAX], *p;
156 int r;
157
158 p = avahi_unescape_label(&a, ca, sizeof(ca));
159 assert(p);
160 p = avahi_unescape_label(&b, cb, sizeof(cb));
161 assert(p);
162
163 if ((r = strcmp(ca, cb)))
164 return r;
165
166 if (!*a && !*b)
167 return 0;
168 }
169 }
170
avahi_domain_ends_with(const char * domain,const char * suffix)171 int avahi_domain_ends_with(const char *domain, const char *suffix) {
172 assert(domain);
173 assert(suffix);
174
175 for (;;) {
176 char dummy[AVAHI_LABEL_MAX], *r;
177
178 if (*domain == 0)
179 return 0;
180
181 if (avahi_domain_equal(domain, suffix))
182 return 1;
183
184 r = avahi_unescape_label(&domain, dummy, sizeof(dummy));
185 assert(r);
186 }
187 }
188
189