daemon/main.c

   1 /* -*- Mode: C ; c-basic-offset: 2 -*- */
   2 /*
   3  * LADI Session Handler (ladish)
   4  *
   5  * Copyright (C) 2008, 2009 Nedko Arnaudov <nedko@arnaudov.name>
   6  * Copyright (C) 2008 Juuso Alasuutari <juuso.alasuutari@gmail.com>
   7  * Copyright (C) 2002 Robert Ham <rah@bash.sh>
   8  *
   9  **************************************************************************
  10  * This file contains the code that implements main() and other top-level functionality
  11  **************************************************************************
  12  *
  13  * LADI Session Handler is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * LADI Session Handler is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with LADI Session Handler. If not, see <http://www.gnu.org/licenses/>
  25  * or write to the Free Software Foundation, Inc.,
  26  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  27  */
  28
  29 #include "common.h"
  30
  31 #include <stdlib.h>
  32 #include <signal.h>
  33 #include <sys/stat.h>
  34
  35 #include "version.h"            /* git version define */
  36 #include "proctitle.h"
  37 #include "loader.h"
  38 #include "sigsegv.h"
  39 #include "control.h"
  40 #include "studio.h"
  41 #include "../dbus_constants.h"
  42 #include "../catdup.h"
  43 #include "dirhelpers.h"
  44
  45 bool g_quit;
  46 const char * g_dbus_unique_name;
  47 object_path_t * g_control_object;
  48 char * g_base_dir;
  49
  50 #if 0
  51 static DBusHandlerResult lashd_client_disconnect_handler(DBusConnection * connection, DBusMessage * message, void * data)
  52 {
  53   /* If the message isn't a signal the object path handler may use it */
  54   if (dbus_message_get_type(message) != DBUS_MESSAGE_TYPE_SIGNAL)
  55   {
  56     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  57   }
  58
  59   const char *member, *name, *old_name;
  60   struct lash_client *client;
  61
  62   if (!(member = dbus_message_get_member(message)))
  63   {
  64     lash_error("Received JACK signal with NULL member");
  65     return DBUS_HANDLER_RESULT_HANDLED;
  66   }
  67
  68   if (strcmp(member, "NameOwnerChanged") != 0)
  69   {
  70     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  71   }
  72
  73   dbus_error_init(&err);
  74
  75   if (!dbus_message_get_args(message, &err,
  76                              DBUS_TYPE_STRING, &name,
  77                              DBUS_TYPE_STRING, &old_name,
  78                              DBUS_TYPE_INVALID))
  79   {
  80     lash_error("Cannot get message arguments: %s",
  81                err.message);
  82     dbus_error_free(&err);
  83     return DBUS_HANDLER_RESULT_HANDLED;
  84   }
  85
  86   client = server_find_client_by_dbus_name(old_name);
  87   if (client)
  88   {
  89     client_disconnected(client);
  90     return DBUS_HANDLER_RESULT_HANDLED;
  91   }
  92
  93   else
  94   {
  95     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  96   }
  97 }
  98
  99   dbus_bus_add_match(
 100     service->connection,
 101     "type='signal'"
 102     ",sender='org.freedesktop.DBus'"
 103     ",path='/org/freedesktop/DBus'"
 104     ",interface='org.freedesktop.DBus'"
 105     ",member='NameOwnerChanged'"
 106     ",arg2=''",
 107     &err);
 108   if (dbus_error_is_set(&err))
 109   {
 110     lash_error("Failed to add D-Bus match rule: %s", err.message);
 111     dbus_error_free(&err);
 112     goto fail;
 113   }
 114
 115   if (!dbus_connection_add_filter(service->connection, lashd_client_disconnect_handler, NULL, NULL))
 116   {
 117     lash_error("Failed to add D-Bus filter");
 118     goto fail;
 119   }
 120 #endif
 121
 122 static bool connect_dbus(void)
 123 {
 124   int ret;
 125
 126   g_dbus_connection = dbus_bus_get(DBUS_BUS_SESSION, &g_dbus_error);
 127   if (dbus_error_is_set(&g_dbus_error))
 128   {
 129     lash_error("Failed to get bus: %s", g_dbus_error.message);
 130     dbus_error_free(&g_dbus_error);
 131     goto fail;
 132   }
 133
 134   g_dbus_unique_name = dbus_bus_get_unique_name(g_dbus_connection);
 135   if (g_dbus_unique_name == NULL)
 136   {
 137     lash_error("Failed to read unique bus name");
 138     goto unref_connection;
 139   }
 140
 141   lash_info("Connected to local session bus, unique name is \"%s\"", g_dbus_unique_name);
 142
 143   ret = dbus_bus_request_name(g_dbus_connection, SERVICE_NAME, DBUS_NAME_FLAG_DO_NOT_QUEUE, &g_dbus_error);
 144   if (ret == -1)
 145   {
 146     lash_error("Failed to acquire bus name: %s", g_dbus_error.message);
 147     dbus_error_free(&g_dbus_error);
 148     goto unref_connection;
 149   }
 150
 151   if (ret == DBUS_REQUEST_NAME_REPLY_EXISTS)
 152   {
 153     lash_error("Requested connection name already exists");
 154     goto unref_connection;
 155   }
 156
 157   g_control_object = object_path_new(CONTROL_OBJECT_PATH, NULL, 1, &g_lashd_interface_control);
 158   if (g_control_object == NULL)
 159   {
 160     goto unref_connection;
 161   }
 162
 163   if (!object_path_register(g_dbus_connection, g_control_object))
 164   {
 165     goto destroy_control_object;
 166   }
 167
 168   return true;
 169
 170 destroy_control_object:
 171   object_path_destroy(g_dbus_connection, g_control_object);
 172 unref_connection:
 173   dbus_connection_unref(g_dbus_connection);
 174
 175 fail:
 176   return false;
 177 }
 178
 179 static void disconnect_dbus(void)
 180 {
 181   object_path_destroy(g_dbus_connection, g_control_object);
 182   dbus_connection_unref(g_dbus_connection);
 183 }
 184
 185 static void on_child_exit(pid_t pid)
 186 {
 187   //client_disconnected(server_find_client_by_pid(child_ptr->pid));
 188 }
 189
 190 void term_signal_handler(int signum)
 191 {
 192   lash_info("Caught signal %d (%s), terminating", signum, strsignal(signum));
 193   g_quit = true;
 194 }
 195
 196 bool install_term_signal_handler(int signum, bool ignore_if_already_ignored)
 197 {
 198   sig_t sigh;
 199
 200   sigh = signal(signum, term_signal_handler);
 201   if (sigh == SIG_ERR)
 202   {
 203     lash_error("signal() failed to install handler function for signal %d.", signum);
 204     return false;
 205   }
 206
 207   if (sigh == SIG_IGN && ignore_if_already_ignored)
 208   {
 209     signal(SIGTERM, SIG_IGN);
 210   }
 211
 212   return true;
 213 }
 214
 215 bool init_paths(void)
 216 {
 217   const char * home_dir;
 218
 219   home_dir = getenv("HOME");
 220   if (home_dir == NULL)
 221   {
 222     lash_error("Environment variable HOME not set");
 223     return false;
 224   }
 225
 226   g_base_dir = catdup(home_dir, BASE_DIR);
 227   if (g_base_dir == NULL)
 228   {
 229     lash_error("catdup failed for '%s' and '%s'", home_dir, BASE_DIR);
 230     return false;
 231   }
 232
 233   if (!ensure_dir_exist(g_base_dir, 0700))
 234   {
 235     free(g_base_dir);
 236     return false;
 237   }
 238
 239   return true;
 240 }
 241
 242 void uninit_paths(void)
 243 {
 244   free(g_base_dir);
 245 }
 246
 247 int main(int argc, char ** argv, char ** envp)
 248 {
 249   struct stat st;
 250   char timestamp_str[26];
 251   int ret;
 252
 253   st.st_mtime = 0;
 254   stat(argv[0], &st);
 255   ctime_r(&st.st_mtime, timestamp_str);
 256   timestamp_str[24] = 0;
 257
 258   lash_init_setproctitle(argc, argv, envp);
 259
 260   dbus_threads_init_default();
 261
 262   lash_info("------------------");
 263   lash_info("LADI session handler activated. Version %s (%s) built on %s", PACKAGE_VERSION, GIT_VERSION, timestamp_str);
 264
 265   ret = EXIT_FAILURE;
 266
 267   if (!init_paths())
 268   {
 269     goto exit;
 270   }
 271
 272   loader_init(on_child_exit);
 273
 274   if (!connect_dbus())
 275   {
 276     lash_error("Failed to connecto to D-Bus");
 277     goto uninit_loader;
 278   }
 279
 280   /* install the signal handlers */
 281   install_term_signal_handler(SIGTERM, false);
 282   install_term_signal_handler(SIGINT, true);
 283   install_term_signal_handler(SIGHUP, true);
 284   if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
 285   {
 286     lash_error("signal(SIGPIPE, SIG_IGN).");
 287   }
 288
 289   /* setup our SIGSEGV magic that prints nice stack in our logfile */
 290   setup_sigsegv();
 291
 292   if (!studio_init())
 293   {
 294     goto uninit_dbus;
 295   }
 296
 297   while (!g_quit)
 298   {
 299     dbus_connection_read_write_dispatch(g_dbus_connection, 50);
 300     loader_run();
 301     studio_run();
 302   }
 303
 304   ret = EXIT_SUCCESS;
 305
 306   lash_debug("Finished, cleaning up");
 307
 308   studio_uninit();
 309
 310 uninit_dbus:
 311   disconnect_dbus();
 312
 313 uninit_loader:
 314   loader_uninit();
 315
 316   uninit_paths();
 317
 318 exit:
 319   lash_debug("Cleaned up, exiting");
 320
 321   lash_info("LADI session handler deactivated");
 322   lash_info("------------------");
 323
 324   exit(EXIT_SUCCESS);
 325 }