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 #include "../proxies/a2j_proxy.h"
  45
  46 bool g_quit;
  47 const char * g_dbus_unique_name;
  48 dbus_object_path g_control_object;
  49 char * g_base_dir;
  50
  51 #if 0
  52 static DBusHandlerResult lashd_client_disconnect_handler(DBusConnection * connection, DBusMessage * message, void * data)
  53 {
  54   /* If the message isn't a signal the object path handler may use it */
  55   if (dbus_message_get_type(message) != DBUS_MESSAGE_TYPE_SIGNAL)
  56   {
  57     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  58   }
  59
  60   const char *member, *name, *old_name;
  61   struct lash_client *client;
  62
  63   if (!(member = dbus_message_get_member(message)))
  64   {
  65     log_error("Received JACK signal with NULL member");
  66     return DBUS_HANDLER_RESULT_HANDLED;
  67   }
  68
  69   if (strcmp(member, "NameOwnerChanged") != 0)
  70   {
  71     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  72   }
  73
  74   dbus_error_init(&err);
  75
  76   if (!dbus_message_get_args(message, &err,
  77                              DBUS_TYPE_STRING, &name,
  78                              DBUS_TYPE_STRING, &old_name,
  79                              DBUS_TYPE_INVALID))
  80   {
  81     log_error("Cannot get message arguments: %s",
  82                err.message);
  83     dbus_error_free(&err);
  84     return DBUS_HANDLER_RESULT_HANDLED;
  85   }
  86
  87   client = server_find_client_by_dbus_name(old_name);
  88   if (client)
  89   {
  90     client_disconnected(client);
  91     return DBUS_HANDLER_RESULT_HANDLED;
  92   }
  93
  94   else
  95   {
  96     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  97   }
  98 }
  99
 100   dbus_bus_add_match(
 101     service->connection,
 102     "type='signal'"
 103     ",sender='org.freedesktop.DBus'"
 104     ",path='/org/freedesktop/DBus'"
 105     ",interface='org.freedesktop.DBus'"
 106     ",member='NameOwnerChanged'"
 107     ",arg2=''",
 108     &err);
 109   if (dbus_error_is_set(&err))
 110   {
 111     log_error("Failed to add D-Bus match rule: %s", err.message);
 112     dbus_error_free(&err);
 113     goto fail;
 114   }
 115
 116   if (!dbus_connection_add_filter(service->connection, lashd_client_disconnect_handler, NULL, NULL))
 117   {
 118     log_error("Failed to add D-Bus filter");
 119     goto fail;
 120   }
 121 #endif
 122
 123 static bool connect_dbus(void)
 124 {
 125   int ret;
 126
 127   dbus_error_init(&g_dbus_error);
 128
 129   g_dbus_connection = dbus_bus_get(DBUS_BUS_SESSION, &g_dbus_error);
 130   if (dbus_error_is_set(&g_dbus_error))
 131   {
 132     log_error("Failed to get bus: %s", g_dbus_error.message);
 133     dbus_error_free(&g_dbus_error);
 134     goto fail;
 135   }
 136
 137   g_dbus_unique_name = dbus_bus_get_unique_name(g_dbus_connection);
 138   if (g_dbus_unique_name == NULL)
 139   {
 140     log_error("Failed to read unique bus name");
 141     goto unref_connection;
 142   }
 143
 144   log_info("Connected to local session bus, unique name is \"%s\"", g_dbus_unique_name);
 145
 146   ret = dbus_bus_request_name(g_dbus_connection, SERVICE_NAME, DBUS_NAME_FLAG_DO_NOT_QUEUE, &g_dbus_error);
 147   if (ret == -1)
 148   {
 149     log_error("Failed to acquire bus name: %s", g_dbus_error.message);
 150     dbus_error_free(&g_dbus_error);
 151     goto unref_connection;
 152   }
 153
 154   if (ret == DBUS_REQUEST_NAME_REPLY_EXISTS)
 155   {
 156     log_error("Requested connection name already exists");
 157     goto unref_connection;
 158   }
 159
 160   g_control_object = dbus_object_path_new(CONTROL_OBJECT_PATH, &g_lashd_interface_control, NULL, NULL);
 161   if (g_control_object == NULL)
 162   {
 163     goto unref_connection;
 164   }
 165
 166   if (!dbus_object_path_register(g_dbus_connection, g_control_object))
 167   {
 168     goto destroy_control_object;
 169   }
 170
 171   return true;
 172
 173 destroy_control_object:
 174   dbus_object_path_destroy(g_dbus_connection, g_control_object);
 175 unref_connection:
 176   dbus_connection_unref(g_dbus_connection);
 177
 178 fail:
 179   return false;
 180 }
 181
 182 static void disconnect_dbus(void)
 183 {
 184   dbus_object_path_destroy(g_dbus_connection, g_control_object);
 185   dbus_connection_unref(g_dbus_connection);
 186 }
 187
 188 void term_signal_handler(int signum)
 189 {
 190   log_info("Caught signal %d (%s), terminating", signum, strsignal(signum));
 191   g_quit = true;
 192 }
 193
 194 bool install_term_signal_handler(int signum, bool ignore_if_already_ignored)
 195 {
 196   sig_t sigh;
 197
 198   sigh = signal(signum, term_signal_handler);
 199   if (sigh == SIG_ERR)
 200   {
 201     log_error("signal() failed to install handler function for signal %d.", signum);
 202     return false;
 203   }
 204
 205   if (sigh == SIG_IGN && ignore_if_already_ignored)
 206   {
 207     signal(SIGTERM, SIG_IGN);
 208   }
 209
 210   return true;
 211 }
 212
 213 bool init_paths(void)
 214 {
 215   const char * home_dir;
 216
 217   home_dir = getenv("HOME");
 218   if (home_dir == NULL)
 219   {
 220     log_error("Environment variable HOME not set");
 221     return false;
 222   }
 223
 224   g_base_dir = catdup(home_dir, BASE_DIR);
 225   if (g_base_dir == NULL)
 226   {
 227     log_error("catdup failed for '%s' and '%s'", home_dir, BASE_DIR);
 228     return false;
 229   }
 230
 231   if (!ensure_dir_exist(g_base_dir, 0700))
 232   {
 233     free(g_base_dir);
 234     return false;
 235   }
 236
 237   return true;
 238 }
 239
 240 void uninit_paths(void)
 241 {
 242   free(g_base_dir);
 243 }
 244
 245 int main(int argc, char ** argv, char ** envp)
 246 {
 247   struct stat st;
 248   char timestamp_str[26];
 249   int ret;
 250
 251   st.st_mtime = 0;
 252   stat(argv[0], &st);
 253   ctime_r(&st.st_mtime, timestamp_str);
 254   timestamp_str[24] = 0;
 255
 256   lash_init_setproctitle(argc, argv, envp);
 257
 258   dbus_threads_init_default();
 259
 260   log_info("------------------");
 261   log_info("LADI session handler activated. Version %s (%s) built on %s", PACKAGE_VERSION, GIT_VERSION, timestamp_str);
 262
 263   ret = EXIT_FAILURE;
 264
 265   if (!init_paths())
 266   {
 267     goto exit;
 268   }
 269
 270   loader_init(studio_on_child_exit);
 271
 272   if (!connect_dbus())
 273   {
 274     log_error("Failed to connecto to D-Bus");
 275     goto uninit_loader;
 276   }
 277
 278   /* install the signal handlers */
 279   install_term_signal_handler(SIGTERM, false);
 280   install_term_signal_handler(SIGINT, true);
 281   install_term_signal_handler(SIGHUP, true);
 282   if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
 283   {
 284     log_error("signal(SIGPIPE, SIG_IGN).");
 285   }
 286
 287   /* setup our SIGSEGV magic that prints nice stack in our logfile */
 288   setup_sigsegv();
 289
 290   a2j_proxy_init();
 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   log_debug("Finished, cleaning up");
 307
 308   studio_uninit();
 309
 310   a2j_proxy_uninit();
 311
 312 uninit_dbus:
 313   disconnect_dbus();
 314
 315 uninit_loader:
 316   loader_uninit();
 317
 318   uninit_paths();
 319
 320 exit:
 321   log_debug("Cleaned up, exiting");
 322
 323   log_info("LADI session handler deactivated");
 324   log_info("------------------");
 325
 326   exit(EXIT_SUCCESS);
 327 }