src/interfaces/logind/logind.c

   1 /*
   2  * Copyright (c) 2014 Ian Sutton <ian@kremlin.cc>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <unistd.h>
  18 #include <limits.h>
  19 #include <signal.h>
  20
  21 #include <sys/param.h>
  22 #include <string.h>
  23
  24 #include <glib/gprintf.h>
  25 #include <glib-unix.h>
  26 #include <polkit/polkit.h>
  27
  28 #include "logind-gen.h"
  29 #include "logind.h"
  30
  31 #include "../../polkit-auth.h"
  32
  33 GPtrArray *logind_freeable;
  34 Login1Manager *logind_interf;
  35
  36 GMainLoop *logind_loop;
  37
  38 guint bus_descriptor;
  39 gboolean dbus_interface_exported; /* reliable because of gdbus operational guarantees */
  40
  41 /* --- begin method/property/dbus signal code --- */
  42
  43 /*static gboolean
  44 on_handle_set_hostname(Login1Manager *hn1_passed_interf,
  45                        GDBusMethodInvocation *invoc,
  46                        const gchar *greet,
  47                        gpointer data) {
  48     return FALSE;
  49 }*/
  50
  51 /*const gchar *
  52 our_get_hostname() {
  53
  54     gchar *hostname_buf, *ret;
  55     size_t hostname_divider;
  56
  57     hostname_buf = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  58     ret          = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  59     g_ptr_array_add(logind_freeable, hostname_buf);
  60     g_ptr_array_add(logind_freeable, ret);
  61
  62     if(gethostname(hostname_buf, MAXHOSTNAMELEN))
  63         return "";
  64
  65     hostname_divider = strcspn(hostname_buf, ".");
  66
  67     return strncpy(ret, hostname_buf, hostname_divider);
  68 }*/
  69
  70 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
  71
  72 static void logind_on_bus_acquired(GDBusConnection *conn,
  73                                    const gchar *name,
  74                                    gpointer user_data) {
  75
  76     g_printf("got bus/name, exporting %s's interface...\n", name);
  77
  78     logind_interf = login1_manager_skeleton_new();
  79
  80     /* attach function pointers to generated struct's method handlers
  81     g_signal_connect(logind_interf, "handle-set-hostname", G_CALLBACK(on_handle_set_hostname), NULL); */
  82
  83     /* set our properties before export
  84     login1_manager_set_hostname(logind_interf, our_get_hostname()); */
  85
  86     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(logind_interf),
  87                                          conn,
  88                                          "/org/freedesktop/login1_manager",
  89                                          NULL)) {
  90
  91         g_printf("failed to export %s's interface!\n", name);
  92         logind_mem_clean();
  93
  94     } else {
  95
  96         dbus_interface_exported = TRUE;
  97         g_printf("exported %s's interface on the system bus...\n", name);
  98     }
  99 }
 100
 101 static void logind_on_name_acquired(GDBusConnection *conn,
 102                                     const gchar *name,
 103                                     gpointer user_data) {
 104
 105    g_printf("success!\n");
 106 }
 107
 108 static void logind_on_name_lost(GDBusConnection *conn,
 109                                 const gchar *name,
 110                                 gpointer user_data) {
 111
 112     if(!conn) {
 113
 114         g_printf("failed to connect to the system bus while trying to acquire name '%s': either dbus-daemon isn't running or we don't have permission to push names and/or their interfaces to it.\n", name);
 115
 116     }
 117
 118     g_print("lost name %s, exiting...\n", name);
 119
 120     logind_mem_clean();
 121 }
 122
 123 /* --- end bus/name handlers, begin misc unix functions --- */
 124
 125 /* safe call to clean and then exit
 126  * this stops our GMainLoop sfaely before letting main() return */
 127 void logind_mem_clean() {
 128
 129     g_printf("exiting...\n");
 130
 131     if(dbus_interface_exported)
 132         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(logind_interf));
 133
 134     if(g_main_loop_is_running(logind_loop))
 135         g_main_loop_quit(logind_loop);
 136
 137 }
 138
 139 /* wrapper for glib's unix signal handling; called only once if terminating signal is raised against us */
 140 gboolean unix_sig_terminate_handler(gpointer data) {
 141
 142     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 143
 144     logind_mem_clean();
 145     return G_SOURCE_REMOVE;
 146 }
 147
 148 void set_signal_handlers() {
 149
 150     /* we don't care about its descriptor, we never need to unregister these */
 151     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 152     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 153     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 154 }
 155
 156 int main() {
 157
 158     set_signal_handlers();
 159
 160     logind_loop = g_main_loop_new(NULL, TRUE);
 161     logind_freeable = g_ptr_array_new();
 162
 163      bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 164                                     "org.freedesktop.login1_manager",
 165                                     G_BUS_NAME_OWNER_FLAGS_NONE,
 166                                     logind_on_bus_acquired,
 167                                     logind_on_name_acquired,
 168                                     logind_on_name_lost,
 169                                     NULL,
 170                                     NULL);
 171
 172     g_main_loop_run(logind_loop);
 173     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 174     g_main_loop_unref(logind_loop);
 175
 176     /* guaranteed unownable */
 177     g_bus_unown_name(bus_descriptor);
 178
 179     /* at this point no operations can occur with our data, it is safe to free it + its container */
 180      g_ptr_array_free(logind_freeable, TRUE);
 181
 182
 183     return 0;
 184 }