1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ 2 /* dbus-misc.c A few assorted public functions that don't fit elsewhere 3 * 4 * Copyright (C) 2006 Red Hat, Inc. 5 * 6 * Licensed under the Academic Free License version 2.1 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 * 22 */ 23 24 #include <config.h> 25 #include "dbus-misc.h" 26 #include "dbus-internals.h" 27 #include "dbus-string.h" 28 29 /** 30 * @defgroup DBusMisc Miscellaneous 31 * @ingroup DBus 32 * @brief Miscellaneous API that doesn't cleanly fit anywhere else 33 * 34 * @{ 35 */ 36 37 /** 38 * Obtains the machine UUID of the machine this process is running on. 39 * 40 * The returned string must be freed with dbus_free(). 41 * 42 * This UUID is guaranteed to remain the same until the next reboot 43 * (unless the sysadmin foolishly changes it and screws themselves). 44 * It will usually remain the same across reboots also, but hardware 45 * configuration changes or rebuilding the machine could break that. 46 * 47 * The idea is that two processes with the same machine ID should be 48 * able to use shared memory, UNIX domain sockets, process IDs, and other 49 * features of the OS that require both processes to be running 50 * on the same OS kernel instance. 51 * 52 * The machine ID can also be used to create unique per-machine 53 * instances. For example, you could use it in bus names or 54 * X selection names. 55 * 56 * The machine ID is preferred over the machine hostname, because 57 * the hostname is frequently set to "localhost.localdomain" and 58 * may also change at runtime. 59 * 60 * You can get the machine ID of a remote application by invoking the 61 * method GetMachineId from interface org.freedesktop.DBus.Peer. 62 * 63 * If the remote application has the same machine ID as the one 64 * returned by this function, then the remote application is on the 65 * same machine as your application. 66 * 67 * The UUID is not a UUID in the sense of RFC4122; the details 68 * are explained in the D-Bus specification. 69 * 70 * @returns a 32-byte-long hex-encoded UUID string, or #NULL if insufficient memory 71 */ 72 char* 73 dbus_get_local_machine_id (void) 74 { 75 DBusString uuid; 76 char *s; 77 78 s = NULL; 79 80 if (!_dbus_string_init (&uuid)) 81 return NULL; 82 83 if (!_dbus_get_local_machine_uuid_encoded (&uuid) || 84 !_dbus_string_steal_data (&uuid, &s)) 85 { 86 _dbus_string_free (&uuid); 87 return NULL; 88 } 89 else 90 { 91 _dbus_string_free (&uuid); 92 return s; 93 } 94 95 } 96 97 /** 98 * @def DBUS_MAJOR_VERSION 99 * 100 * The COMPILE TIME major version of libdbus, that is, the "X" in "X.Y.Z", 101 * as an integer literal. Consider carefully whether to use this or the 102 * runtime version from dbus_get_version(). 103 */ 104 105 /** 106 * @def DBUS_MINOR_VERSION 107 * 108 * The COMPILE TIME minor version of libdbus, that is, the "Y" in "X.Y.Z", 109 * as an integer literal. Consider carefully whether to use this or the 110 * runtime version from dbus_get_version(). 111 */ 112 113 /** 114 * @def DBUS_MICRO_VERSION 115 * 116 * The COMPILE TIME micro version of libdbus, that is, the "Z" in "X.Y.Z", 117 * as an integer literal. Consider carefully whether to use this or the 118 * runtime version from dbus_get_version(). 119 */ 120 121 /** 122 * @def DBUS_VERSION 123 * 124 * The COMPILE TIME version of libdbus, as a single integer that has 0 in the most 125 * significant byte, the major version in the next most significant byte, 126 * the minor version in the third most significant, and the micro version in the 127 * least significant byte. This means two DBUS_VERSION can be compared to see 128 * which is higher. 129 * 130 * Consider carefully whether to use this or the runtime version from 131 * dbus_get_version(). 132 */ 133 134 /** 135 * @def DBUS_VERSION_STRING 136 * 137 * The COMPILE TIME version of libdbus, as a string "X.Y.Z". 138 * 139 * Consider carefully whether to use this or the runtime version from 140 * dbus_get_version(). 141 */ 142 143 /** 144 * Gets the DYNAMICALLY LINKED version of libdbus. Alternatively, there 145 * are macros #DBUS_MAJOR_VERSION, #DBUS_MINOR_VERSION, #DBUS_MICRO_VERSION, 146 * and #DBUS_VERSION which allow you to test the VERSION YOU ARE COMPILED AGAINST. 147 * In other words, you can get either the runtime or the compile-time version. 148 * Think carefully about which of these you want in a given case. 149 * 150 * The libdbus full version number is "MAJOR.MINOR.MICRO" where the 151 * MINOR changes if API is added, and the MICRO changes with each 152 * release of a MAJOR.MINOR series. The MINOR is an odd number for 153 * development releases and an even number for stable releases. 154 * 155 * @param major_version_p pointer to return the major version, or #NULL 156 * @param minor_version_p pointer to return the minor version, or #NULL 157 * @param micro_version_p pointer to return the micro version, or #NULL 158 * 159 */ 160 void 161 dbus_get_version (int *major_version_p, 162 int *minor_version_p, 163 int *micro_version_p) 164 { 165 if (major_version_p) 166 *major_version_p = DBUS_MAJOR_VERSION; 167 if (minor_version_p) 168 *minor_version_p = DBUS_MINOR_VERSION; 169 if (micro_version_p) 170 *micro_version_p = DBUS_MICRO_VERSION; 171 } 172 173 174 /** @} */ /* End of public API */ 175 176 #ifdef DBUS_BUILD_TESTS 177 178 #ifndef DOXYGEN_SHOULD_SKIP_THIS 179 180 #include "dbus-test.h" 181 #include <stdlib.h> 182 183 184 dbus_bool_t 185 _dbus_misc_test (void) 186 { 187 int major, minor, micro; 188 DBusString str; 189 190 /* make sure we don't crash on NULL */ 191 dbus_get_version (NULL, NULL, NULL); 192 193 /* Now verify that all the compile-time version stuff 194 * is right and matches the runtime. These tests 195 * are mostly intended to catch various kinds of 196 * typo (mixing up major and minor, that sort of thing). 197 */ 198 dbus_get_version (&major, &minor, µ); 199 200 _dbus_assert (major == DBUS_MAJOR_VERSION); 201 _dbus_assert (minor == DBUS_MINOR_VERSION); 202 _dbus_assert (micro == DBUS_MICRO_VERSION); 203 204 #define MAKE_VERSION(x, y, z) (((x) << 16) | ((y) << 8) | (z)) 205 206 /* check that MAKE_VERSION works and produces the intended ordering */ 207 _dbus_assert (MAKE_VERSION (1, 0, 0) > MAKE_VERSION (0, 0, 0)); 208 _dbus_assert (MAKE_VERSION (1, 1, 0) > MAKE_VERSION (1, 0, 0)); 209 _dbus_assert (MAKE_VERSION (1, 1, 1) > MAKE_VERSION (1, 1, 0)); 210 211 _dbus_assert (MAKE_VERSION (2, 0, 0) > MAKE_VERSION (1, 1, 1)); 212 _dbus_assert (MAKE_VERSION (2, 1, 0) > MAKE_VERSION (1, 1, 1)); 213 _dbus_assert (MAKE_VERSION (2, 1, 1) > MAKE_VERSION (1, 1, 1)); 214 215 /* check DBUS_VERSION */ 216 _dbus_assert (MAKE_VERSION (major, minor, micro) == DBUS_VERSION); 217 218 /* check that ordering works with DBUS_VERSION */ 219 _dbus_assert (MAKE_VERSION (major - 1, minor, micro) < DBUS_VERSION); 220 _dbus_assert (MAKE_VERSION (major, minor - 1, micro) < DBUS_VERSION); 221 _dbus_assert (MAKE_VERSION (major, minor, micro - 1) < DBUS_VERSION); 222 223 _dbus_assert (MAKE_VERSION (major + 1, minor, micro) > DBUS_VERSION); 224 _dbus_assert (MAKE_VERSION (major, minor + 1, micro) > DBUS_VERSION); 225 _dbus_assert (MAKE_VERSION (major, minor, micro + 1) > DBUS_VERSION); 226 227 /* Check DBUS_VERSION_STRING */ 228 229 if (!_dbus_string_init (&str)) 230 _dbus_assert_not_reached ("no memory"); 231 232 if (!(_dbus_string_append_int (&str, major) && 233 _dbus_string_append_byte (&str, '.') && 234 _dbus_string_append_int (&str, minor) && 235 _dbus_string_append_byte (&str, '.') && 236 _dbus_string_append_int (&str, micro))) 237 _dbus_assert_not_reached ("no memory"); 238 239 _dbus_assert (_dbus_string_equal_c_str (&str, DBUS_VERSION_STRING)); 240 241 _dbus_string_free (&str); 242 243 return TRUE; 244 } 245 246 #endif /* !DOXYGEN_SHOULD_SKIP_THIS */ 247 248 #endif 249
