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 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__ 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 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 } 137 138 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 } 146 147 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 } 170 171 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