2 * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
4 * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <glib/gi18n.h>
30 #include "preferences.h"
31 #include "vik_compat.h"
33 #define MC_KEY_SIZE 64
35 typedef struct _List {
40 /* a circular linked list, a pointer to the tail, and the tail points to the head */
41 /* this is so we can free the last */
42 static List *queue_tail = NULL;
43 static int queue_count = 0;
45 static guint32 cache_size = 0;
46 static guint32 max_cache_size = VIK_CONFIG_MAPCACHE_SIZE * 1024 * 1024;
48 static GHashTable *cache = NULL;
50 static GMutex *mc_mutex = NULL;
52 #define HASHKEY_FORMAT_STRING "%d-%d-%d-%d-%d-%d-%d-%.3f-%.3f"
53 #define HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA "%d-%d-%d-%d-%d-%d-"
54 #define HASHKEY_FORMAT_STRING_TYPE "%d-"
56 static VikLayerParamScale params_scales[] = {
57 /* min, max, step, digits (decimal places) */
61 static VikLayerParam prefs[] = {
62 { VIK_LAYER_NUM_TYPES, VIKING_PREFERENCES_NAMESPACE "mapcache_size", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Map cache memory size (MB):"), VIK_LAYER_WIDGET_HSCALE, params_scales, NULL, NULL, NULL, NULL, NULL },
65 void a_mapcache_init ()
67 VikLayerParamData tmp;
68 tmp.u = VIK_CONFIG_MAPCACHE_SIZE;
69 a_preferences_register(prefs, tmp, VIKING_PREFERENCES_GROUP_KEY);
71 mc_mutex = vik_mutex_new ();
72 cache = g_hash_table_new_full ( g_str_hash, g_str_equal, g_free, g_object_unref );
75 static void cache_add(gchar *key, GdkPixbuf *pixbuf)
77 #if !GLIB_CHECK_VERSION(2,26,0)
78 // Only later versions of GLib actually return a value for this function
79 // Annoyingly the documentation doesn't say anything about this interface change :(
80 if ( g_hash_table_insert ( cache, key, pixbuf ) )
82 g_hash_table_insert ( cache, key, pixbuf );
85 cache_size += gdk_pixbuf_get_rowstride(pixbuf) * gdk_pixbuf_get_height(pixbuf);
90 static void cache_remove(const gchar *key)
92 GdkPixbuf *buf = g_hash_table_lookup ( cache, key );
94 cache_size -= gdk_pixbuf_get_rowstride(buf) * gdk_pixbuf_get_height(buf);
96 g_hash_table_remove ( cache, key );
100 /* returns key from head, adds on newtailkey to tail. */
101 static gchar *list_shift_add_entry ( gchar *newtailkey )
103 gchar *oldheadkey = queue_tail->next->key;
104 queue_tail->next->key = newtailkey;
105 queue_tail = queue_tail->next;
109 static gchar *list_shift ()
111 gchar *oldheadkey = queue_tail->next->key;
112 List *oldhead = queue_tail->next;
113 queue_tail->next = queue_tail->next->next;
119 /* adds key to tail */
120 static void list_add_entry ( gchar *key )
122 List *newlist = g_malloc ( sizeof ( List ) );
125 newlist->next = queue_tail->next;
126 queue_tail->next = newlist;
127 queue_tail = newlist;
129 newlist->next = newlist;
130 queue_tail = newlist;
135 void a_mapcache_add ( GdkPixbuf *pixbuf, gint x, gint y, gint z, guint16 type, gint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor, const gchar* name )
137 guint nn = name ? g_str_hash ( name ) : 0;
138 gchar *key = g_strdup_printf ( HASHKEY_FORMAT_STRING, type, x, y, z, zoom, nn, alpha, xshrinkfactor, yshrinkfactor );
140 g_mutex_lock(mc_mutex);
141 cache_add(key, pixbuf);
143 // TODO: that should be done on preference change only...
144 max_cache_size = a_preferences_get(VIKING_PREFERENCES_NAMESPACE "mapcache_size")->u * 1024 * 1024;
146 if ( cache_size > max_cache_size ) {
148 gchar *oldkey = list_shift_add_entry ( key );
149 cache_remove(oldkey);
151 while ( cache_size > max_cache_size &&
152 (queue_tail->next != queue_tail) ) { /* make sure there's more than one thing to delete */
153 oldkey = list_shift ();
154 cache_remove(oldkey);
157 /* chop off 'start' etc */
159 list_add_entry ( key );
160 /* business as usual */
162 g_mutex_unlock(mc_mutex);
165 if ( (++tmp == 100 )) { g_debug("DEBUG: cache count=%d size=%u list count=%d\n", g_hash_table_size(cache), cache_size, queue_count ); tmp=0; }
168 GdkPixbuf *a_mapcache_get ( gint x, gint y, gint z, guint16 type, gint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor, const gchar* name )
170 static char key[MC_KEY_SIZE];
171 guint nn = name ? g_str_hash ( name ) : 0;
172 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING, type, x, y, z, zoom, nn, alpha, xshrinkfactor, yshrinkfactor );
173 return g_hash_table_lookup ( cache, key );
177 * Common function to remove cache items for keys starting with the specified string
179 static void flush_matching ( gchar *str )
181 if ( queue_tail == NULL )
184 List *loop = queue_tail;
186 gint len = strlen(str);
188 g_mutex_lock(mc_mutex);
192 if ( strncmp(tmp->key, str, len) == 0 )
194 cache_remove(tmp->key);
195 if ( tmp == loop ) /* we deleted the last thing in the queue! */
196 loop = queue_tail = NULL;
198 loop->next = tmp->next;
199 if ( tmp == queue_tail )
200 queue_tail = tmp->next;
210 } while ( loop && (loop != queue_tail || tmp == NULL) );
211 /* loop thru list, looking for the one, compare first whatever chars */
214 g_mutex_unlock(mc_mutex);
218 * Appears this is only used when redownloading tiles (i.e. to invalidate old images)
220 void a_mapcache_remove_all_shrinkfactors ( gint x, gint y, gint z, guint16 type, gint zoom )
222 char key[MC_KEY_SIZE];
223 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA, type, x, y, z, zoom, 0 );
224 flush_matching ( key );
227 void a_mapcache_flush ()
229 List *loop = queue_tail;
232 if ( queue_tail == NULL )
235 g_mutex_lock(mc_mutex);
238 cache_remove(tmp->key);
239 if ( tmp == queue_tail ) /* we deleted the last thing in the queue */
240 loop = queue_tail = NULL;
242 loop->next = tmp->next;
247 g_mutex_unlock(mc_mutex);
251 * a_mapcache_flush_type:
252 * @type: Specified map type
254 * Just remove cache items for the specified map type
255 * i.e. all related xyz+zoom+alpha+etc...
257 void a_mapcache_flush_type ( guint16 type )
259 char key[MC_KEY_SIZE];
260 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING_TYPE, type );
261 flush_matching ( key );
264 void a_mapcache_uninit ()
266 g_hash_table_destroy ( cache );
269 vik_mutex_free (mc_mutex);
272 // Size of mapcache in memory
273 gint a_mapcache_get_size ()
278 // Count of items in the mapcache
279 gint a_mapcache_get_count ()
281 return g_hash_table_size ( cache );