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
  27 #include "logind-gen.h"
  28 #include "logind.h"
  29
  30 GPtrArray *logind_freeable;
  31 Login1Manager *logind_interf;
  32
  33 GMainLoop *logind_loop;
  34
  35 guint bus_descriptor;
  36 gboolean dbus_interface_exported; /* reliable because of gdbus operational guarantees */
  37
  38 /* --- begin method/property/dbus signal code --- */
  39
  40 /*static gboolean
  41 on_handle_set_hostname(Login1Manager *hn1_passed_interf,
  42                        GDBusMethodInvocation *invoc,
  43                        const gchar *greet,
  44                        gpointer data) {
  45     return FALSE;
  46 }*/
  47
  48 /*const gchar *
  49 our_get_hostname() {
  50
  51         gchar *hostname_buf, *ret;
  52         size_t hostname_divider;
  53
  54         hostname_buf = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  55         ret          = (gchar*) g_malloc0(MAXHOSTNAMELEN);
  56         g_ptr_array_add(logind_freeable, hostname_buf);
  57         g_ptr_array_add(logind_freeable, ret);
  58
  59         if(gethostname(hostname_buf, MAXHOSTNAMELEN))
  60                 return "";
  61
  62         hostname_divider = strcspn(hostname_buf, ".");
  63
  64         return strncpy(ret, hostname_buf, hostname_divider);
  65 }*/
  66
  67 /* --- end method/property/dbus signal code, begin bus/name handlers --- */
  68
  69 static void logind_on_bus_acquired(GDBusConnection *conn,
  70                                    const gchar *name,
  71                                    gpointer user_data) {
  72
  73     g_print("got bus/name, exporting %s's interface...\n", name);
  74
  75     logind_interf = login1_manager_skeleton_new();
  76
  77     /* attach function pointers to generated struct's method handlers
  78     g_signal_connect(logind_interf, "handle-set-hostname", G_CALLBACK(on_handle_set_hostname), NULL); */
  79
  80     /* set our properties before export
  81     login1_manager_set_hostname(logind_interf, our_get_hostname()); */
  82
  83     if(!g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(logind_interf),
  84                                          conn,
  85                                          "/org/freedesktop/login1_manager",
  86                                          NULL)) {
  87
  88         g_printf("failed to export %s's interface!\n", name);
  89         logind_mem_clean();
  90
  91     } else {
  92
  93         dbus_interface_exported = TRUE;
  94         g_printf("exported %s's interface on the system bus...\n", name);
  95     }
  96 }
  97
  98 static void logind_on_name_acquired(GDBusConnection *conn,
  99                                         const gchar *name,
 100                                     gpointer user_data) {
 101
 102    g_printf("success!\n");
 103 }
 104
 105 static void logind_on_name_lost(GDBusConnection *conn,
 106                                 const gchar *name,
 107                                 gpointer user_data) {
 108
 109     if(!conn) {
 110
 111         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);
 112
 113     }
 114
 115     g_print("lost name %s, exiting...\n", name);
 116
 117     logind_mem_clean();
 118 }
 119
 120 /* --- end bus/name handlers, begin misc unix functions --- */
 121
 122 /* safe call to clean and then exit
 123  * this stops our GMainLoop sfaely before letting main() return */
 124 void logind_mem_clean() {
 125
 126     g_printf("exiting...\n");
 127
 128     if(dbus_interface_exported)
 129         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(logind_interf));
 130
 131     if(g_main_loop_is_running(logind_loop))
 132         g_main_loop_quit(logind_loop);
 133
 134 }
 135
 136 /* wrapper for glib's unix signal handling; called only once if terminating signal is raised against us */
 137 gboolean unix_sig_terminate_handler(gpointer data) {
 138
 139     g_printf("caught SIGINT/HUP/TERM, exiting\n");
 140
 141     logind_mem_clean();
 142     return G_SOURCE_REMOVE;
 143 }
 144
 145 void set_signal_handlers() {
 146
 147     /* we don't care about its descriptor, we never need to unregister these */
 148     g_unix_signal_add(SIGINT,  unix_sig_terminate_handler, NULL);
 149     g_unix_signal_add(SIGHUP,  unix_sig_terminate_handler, NULL);
 150     g_unix_signal_add(SIGTERM, unix_sig_terminate_handler, NULL);
 151 }
 152
 153 int main() {
 154
 155     set_signal_handlers();
 156
 157         logind_loop = g_main_loop_new(NULL, TRUE);
 158         logind_freeable = g_ptr_array_new();
 159
 160          bus_descriptor = g_bus_own_name(G_BUS_TYPE_SYSTEM,
 161                                     "org.freedesktop.login1_manager",
 162                                     G_BUS_NAME_OWNER_FLAGS_NONE,
 163                                     logind_on_bus_acquired,
 164                                     logind_on_name_acquired,
 165                                     logind_on_name_lost,
 166                                     NULL,
 167                                     NULL);
 168
 169         g_main_loop_run(logind_loop);
 170     /* runs until single g_main_loop_quit() call is raised inside <interface>_mem_clean() */
 171         g_main_loop_unref(logind_loop);
 172
 173     /* guaranteed unownable */
 174         g_bus_unown_name(bus_descriptor);
 175
 176     /* at this point no operations can occur with our data, it is safe to free it + its container */
 177      g_ptr_array_free(logind_freeable, TRUE);
 178
 179
 180         return 0;
 181 }