Updated German translation.
[platform/upstream/glib.git] / gio / gpollfilemonitor.c
1 /* GIO - GLib Input, Output and Streaming Library
2  * 
3  * Copyright (C) 2006-2007 Red Hat, Inc.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General
16  * Public License along with this library; if not, write to the
17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
18  * Boston, MA 02111-1307, USA.
19  *
20  * Author: Alexander Larsson <alexl@redhat.com>
21  */
22
23 #include "config.h"
24 #include <string.h>
25
26 #include "gpollfilemonitor.h"
27 #include "gfile.h"
28 #include "gfilemonitor.h"
29 #include "gfileinfo.h"
30
31 #include "gioalias.h"
32
33 static gboolean g_poll_file_monitor_cancel (GFileMonitor* monitor);
34 static void schedule_poll_timeout (GPollFileMonitor* poll_monitor);
35
36 struct _GPollFileMonitor
37 {
38   GFileMonitor parent_instance;
39   GFile *file;
40   GFileInfo *last_info;
41   guint timeout;
42 };
43
44 #define POLL_TIME_SECS 5
45
46 #define g_poll_file_monitor_get_type _g_poll_file_monitor_get_type
47 G_DEFINE_TYPE (GPollFileMonitor, g_poll_file_monitor, G_TYPE_FILE_MONITOR)
48
49 static void
50 g_poll_file_monitor_finalize (GObject* object)
51 {
52   GPollFileMonitor* poll_monitor;
53   
54   poll_monitor = G_POLL_FILE_MONITOR (object);
55
56   g_object_unref (poll_monitor->file);
57
58   G_OBJECT_CLASS (g_poll_file_monitor_parent_class)->finalize (object);
59 }
60
61
62 static void
63 g_poll_file_monitor_class_init (GPollFileMonitorClass* klass)
64 {
65   GObjectClass* gobject_class = G_OBJECT_CLASS (klass);
66   GFileMonitorClass *file_monitor_class = G_FILE_MONITOR_CLASS (klass);
67   
68   gobject_class->finalize = g_poll_file_monitor_finalize;
69
70   file_monitor_class->cancel = g_poll_file_monitor_cancel;
71 }
72
73 static void
74 g_poll_file_monitor_init (GPollFileMonitor* poll_monitor)
75 {
76 }
77
78 static int 
79 safe_strcmp (const char *a, 
80              const char *b)
81 {
82   if (a == NULL && b == NULL)
83     return 0;
84   if (a == NULL)
85     return -1;
86   if (b == NULL)
87     return 1;
88   
89   return strcmp (a, b);
90 }
91
92 static int
93 calc_event_type (GFileInfo *last,
94                  GFileInfo *new)
95 {
96   if (last == NULL && new == NULL)
97     return -1;
98
99   if (last == NULL && new != NULL)
100     return G_FILE_MONITOR_EVENT_CREATED;
101   
102   if (last != NULL && new == NULL)
103     return G_FILE_MONITOR_EVENT_DELETED;
104
105   if (safe_strcmp (g_file_info_get_etag (last),
106                    g_file_info_get_etag (new)))
107     return G_FILE_MONITOR_EVENT_CHANGED;
108   
109   if (g_file_info_get_size (last) !=
110       g_file_info_get_size (new))
111     return G_FILE_MONITOR_EVENT_CHANGED;
112
113   return -1;
114 }
115
116 static void
117 got_new_info (GObject      *source_object,
118               GAsyncResult *res,
119               gpointer      user_data)
120 {
121   GPollFileMonitor* poll_monitor = user_data;
122   GFileInfo *info;
123   int event;
124
125   info = g_file_query_info_finish (poll_monitor->file, res, NULL);
126
127   if (!g_file_monitor_is_cancelled (G_FILE_MONITOR (poll_monitor)))
128     {
129       event = calc_event_type (poll_monitor->last_info, info);
130
131       if (event != -1)
132         {
133           g_file_monitor_emit_event (G_FILE_MONITOR (poll_monitor),
134                                      poll_monitor->file,
135                                      NULL, event);
136           /* We're polling so slowly anyway, so always emit the done hint */
137           if (event == G_FILE_MONITOR_EVENT_CHANGED)
138             g_file_monitor_emit_event (G_FILE_MONITOR (poll_monitor),
139                                        poll_monitor->file,
140                                        NULL, G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT);
141         }
142       
143       if (poll_monitor->last_info)
144         {
145           g_object_unref (poll_monitor->last_info);
146           poll_monitor->last_info = NULL;
147         }
148       
149       if (info)
150         poll_monitor->last_info = g_object_ref (info);
151       
152       schedule_poll_timeout (poll_monitor);
153     }
154
155   if (info)
156     g_object_unref (info);
157   
158   g_object_unref (poll_monitor);
159 }
160
161 static gboolean
162 poll_file_timeout (gpointer data)
163 {
164   GPollFileMonitor* poll_monitor = data;
165
166   poll_monitor->timeout = FALSE;
167
168   g_file_query_info_async (poll_monitor->file, G_FILE_ATTRIBUTE_ETAG_VALUE "," G_FILE_ATTRIBUTE_STANDARD_SIZE,
169                          0, 0, NULL, got_new_info, g_object_ref (poll_monitor));
170   
171   return FALSE;
172 }
173
174 static void
175 schedule_poll_timeout (GPollFileMonitor* poll_monitor)
176 {
177   poll_monitor->timeout = g_timeout_add_seconds (POLL_TIME_SECS, poll_file_timeout, poll_monitor);
178  }
179
180 static void
181 got_initial_info (GObject      *source_object,
182                   GAsyncResult *res,
183                   gpointer      user_data)
184 {
185   GPollFileMonitor* poll_monitor = user_data;
186   GFileInfo *info;
187
188   info = g_file_query_info_finish (poll_monitor->file, res, NULL);
189
190   poll_monitor->last_info = info;
191
192   if (!g_file_monitor_is_cancelled (G_FILE_MONITOR (poll_monitor)))
193     schedule_poll_timeout (poll_monitor);
194   
195   g_object_unref (poll_monitor);
196 }
197
198 /**
199  * g_poll_file_monitor_new:
200  * @file: a #GFile.
201  * 
202  * Polls @file for changes.
203  * 
204  * Returns: a new #GFileMonitor for the given #GFile. 
205  **/
206 GFileMonitor*
207 _g_poll_file_monitor_new (GFile *file)
208 {
209   GPollFileMonitor* poll_monitor;
210   
211   poll_monitor = g_object_new (G_TYPE_POLL_FILE_MONITOR, NULL);
212
213   poll_monitor->file = g_object_ref (file);
214
215   g_file_query_info_async (file, G_FILE_ATTRIBUTE_ETAG_VALUE "," G_FILE_ATTRIBUTE_STANDARD_SIZE,
216                            0, 0, NULL, got_initial_info, g_object_ref (poll_monitor));
217   
218   return G_FILE_MONITOR (poll_monitor);
219 }
220
221 static gboolean
222 g_poll_file_monitor_cancel (GFileMonitor* monitor)
223 {
224   GPollFileMonitor *poll_monitor = G_POLL_FILE_MONITOR (monitor);
225   
226   if (poll_monitor->timeout)
227     {
228       g_source_remove (poll_monitor->timeout);
229       poll_monitor->timeout = 0;
230     }
231   
232   return TRUE;
233 }