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 "dbus_iface_control.h"
  40 #include "jack.h"
  41 #include "studio.h"
  42
  43 bool g_quit;
  44 const char * g_dbus_unique_name;
  45 object_path_t * g_control_object;
  46 studio_handle g_studio;
  47
  48 #if 0
  49 static DBusHandlerResult lashd_client_disconnect_handler(DBusConnection * connection, DBusMessage * message, void * data)
  50 {
  51   /* If the message isn't a signal the object path handler may use it */
  52   if (dbus_message_get_type(message) != DBUS_MESSAGE_TYPE_SIGNAL)
  53   {
  54     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  55   }
  56
  57   const char *member, *name, *old_name;
  58   struct lash_client *client;
  59   DBusError err;
  60
  61   if (!(member = dbus_message_get_member(message)))
  62   {
  63     lash_error("Received JACK signal with NULL member");
  64     return DBUS_HANDLER_RESULT_HANDLED;
  65   }
  66
  67   if (strcmp(member, "NameOwnerChanged") != 0)
  68   {
  69     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  70   }
  71
  72   dbus_error_init(&err);
  73
  74   if (!dbus_message_get_args(message, &err,
  75                              DBUS_TYPE_STRING, &name,
  76                              DBUS_TYPE_STRING, &old_name,
  77                              DBUS_TYPE_INVALID))
  78   {
  79     lash_error("Cannot get message arguments: %s",
  80                err.message);
  81     dbus_error_free(&err);
  82     return DBUS_HANDLER_RESULT_HANDLED;
  83   }
  84
  85   client = server_find_client_by_dbus_name(old_name);
  86   if (client)
  87   {
  88     client_disconnected(client);
  89     return DBUS_HANDLER_RESULT_HANDLED;
  90   }
  91
  92   else
  93   {
  94     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  95   }
  96 }
  97
  98   dbus_bus_add_match(
  99     service->connection,
 100     "type='signal'"
 101     ",sender='org.freedesktop.DBus'"
 102     ",path='/org/freedesktop/DBus'"
 103     ",interface='org.freedesktop.DBus'"
 104     ",member='NameOwnerChanged'"
 105     ",arg2=''",
 106     &err);
 107   if (dbus_error_is_set(&err))
 108   {
 109     lash_error("Failed to add D-Bus match rule: %s", err.message);
 110     dbus_error_free(&err);
 111     goto fail;
 112   }
 113
 114   if (!dbus_connection_add_filter(service->connection, lashd_client_disconnect_handler, NULL, NULL))
 115   {
 116     lash_error("Failed to add D-Bus filter");
 117     goto fail;
 118   }
 119 #endif
 120
 121 static bool connect_dbus(void)
 122 {
 123   int ret;
 124
 125   g_dbus_connection = dbus_bus_get(DBUS_BUS_SESSION, &g_dbus_error);
 126   if (dbus_error_is_set(&g_dbus_error))
 127   {
 128     lash_error("Failed to get bus: %s", g_dbus_error.message);
 129     dbus_error_free(&g_dbus_error);
 130     goto fail;
 131   }
 132
 133   g_dbus_unique_name = dbus_bus_get_unique_name(g_dbus_connection);
 134   if (g_dbus_unique_name == NULL)
 135   {
 136     lash_error("Failed to read unique bus name");
 137     goto unref_connection;
 138   }
 139
 140   ret = dbus_bus_request_name(g_dbus_connection, DBUS_NAME_BASE, DBUS_NAME_FLAG_DO_NOT_QUEUE, &g_dbus_error);
 141   if (ret == -1)
 142   {
 143     lash_error("Failed to acquire bus name: %s", g_dbus_error.message);
 144     dbus_error_free(&g_dbus_error);
 145     goto unref_connection;
 146   }
 147
 148   if (ret == DBUS_REQUEST_NAME_REPLY_EXISTS)
 149   {
 150     lash_error("Requested connection name already exists");
 151     goto unref_connection;
 152   }
 153
 154   g_control_object = object_path_new(CONTROL_OBJECT_PATH, NULL, 1, &g_lashd_interface_control, NULL);
 155   if (g_control_object == NULL)
 156   {
 157     goto unref_connection;
 158   }
 159
 160   if (!object_path_register(g_dbus_connection, g_control_object))
 161   {
 162     goto destroy_control_object;
 163   }
 164
 165   return true;
 166
 167 destroy_control_object:
 168   object_path_destroy(g_dbus_connection, g_control_object);
 169 unref_connection:
 170   dbus_connection_unref(g_dbus_connection);
 171
 172 fail:
 173   return false;
 174 }
 175
 176 static void disconnect_dbus(void)
 177 {
 178   object_path_destroy(g_dbus_connection, g_control_object);
 179   dbus_connection_unref(g_dbus_connection);
 180 }
 181
 182 static void on_child_exit(pid_t pid)
 183 {
 184   //client_disconnected(server_find_client_by_pid(child_ptr->pid));
 185 }
 186
 187 void term_signal_handler(int signum)
 188 {
 189   lash_info("Caught signal %d (%s), terminating", signum, strsignal(signum));
 190   g_quit = true;
 191 }
 192
 193 bool install_term_signal_handler(int signum, bool ignore_if_already_ignored)
 194 {
 195   sig_t sigh;
 196
 197   sigh = signal(signum, term_signal_handler);
 198   if (sigh == SIG_ERR)
 199   {
 200     lash_error("signal() failed to install handler function for signal %d.", signum);
 201     return false;
 202   }
 203
 204   if (sigh == SIG_IGN && ignore_if_already_ignored)
 205   {
 206     signal(SIGTERM, SIG_IGN);
 207   }
 208
 209   return true;
 210 }
 211
 212 int main(int argc, char ** argv, char ** envp)
 213 {
 214   struct stat st;
 215   char timestamp_str[26];
 216   int ret;
 217
 218   st.st_mtime = 0;
 219   stat(argv[0], &st);
 220   ctime_r(&st.st_mtime, timestamp_str);
 221   timestamp_str[24] = 0;
 222
 223   lash_init_setproctitle(argc, argv, envp);
 224
 225   dbus_threads_init_default();
 226
 227   lash_info("------------------");
 228   lash_info("LADI session handler activated. Version %s (%s) built on %s", PACKAGE_VERSION, GIT_VERSION, timestamp_str);
 229
 230   ret = EXIT_FAILURE;
 231
 232   loader_init(on_child_exit);
 233
 234   if (!connect_dbus())
 235   {
 236     lash_error("Failed to connecto to D-Bus");
 237     goto uninit_loader;
 238   }
 239
 240   /* install the signal handlers */
 241   install_term_signal_handler(SIGTERM, false);
 242   install_term_signal_handler(SIGINT, true);
 243   install_term_signal_handler(SIGHUP, true);
 244   if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
 245   {
 246     lash_error("signal(SIGPIPE, SIG_IGN).");
 247   }
 248
 249   /* setup our SIGSEGV magic that prints nice stack in our logfile */
 250   setup_sigsegv();
 251
 252   if (!jack_init())
 253   {
 254     goto uninit_dbus;
 255   }
 256
 257   while (!g_quit)
 258   {
 259     dbus_connection_read_write_dispatch(g_dbus_connection, 50);
 260     loader_run();
 261   }
 262
 263   if (g_studio != NULL)
 264   {
 265     studio_destroy(g_studio);
 266     emit_studio_disappeared();
 267   }
 268
 269   ret = EXIT_SUCCESS;
 270
 271   lash_debug("Finished, cleaning up");
 272
 273 uninit_dbus:
 274   jack_uninit();
 275
 276   disconnect_dbus();
 277
 278 uninit_loader:
 279   loader_uninit();
 280
 281   lash_debug("Cleaned up, exiting");
 282
 283   lash_info("LADI session handler deactivated");
 284   lash_info("------------------");
 285
 286   exit(EXIT_SUCCESS);
 287 }