added missing file

1 files changed, 242 insertions, 0 deletions

diff --git a/pango/pangox-fontcache.c b/pango/pangox-fontcache.c
new file mode 100644
index 00000000..b7d7a7fa
--- /dev/null
+++ b/pango/pangox-fontcache.c
@@ -0,0 +1,242 @@
+/* Pango
+ * pango-fontcache.c: Cache of XFontStructs by XLFD
+ *
+ * Copyright (C) 2000 Red Hat Software
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "pangox.h"
+
+/* Font cache
+ */
+
+/* Number of fonts to retain after they are not otherwise referenced.
+ */
+#define CACHE_SIZE 16
+
+typedef struct _CacheEntry CacheEntry;
+
+struct _PangoXFontCache
+{
+  Display *display;
+  
+  GHashTable *forward;
+  GHashTable *back;
+
+  GList *mru;
+  GList *mru_tail;
+  int mru_count;
+};
+
+struct _CacheEntry
+{
+  char *xlfd;
+  XFontStruct *fs;
+
+  gint ref_count;
+  GList *mru;
+};
+
+static void
+free_cache_entry (char *xlfd, CacheEntry *entry, PangoXFontCache *cache)
+{
+  g_free (entry->xlfd);
+  XFreeFont (cache->display, entry->fs);
+
+  g_free (entry);
+}
+
+/**
+ * pango_x_font_cache_free:
+ * @cache: a #PangoXFontCache
+ * 
+ * Free a #PangoXFontCache and all associated memory. All fonts loaded
+ * through this font cache will be freed along with the cache.
+ **/
+void
+pango_x_font_cache_free (PangoXFontCache *cache)
+{
+  g_return_if_fail (cache != NULL);
+  
+  g_hash_table_foreach (cache->forward, (GHFunc)free_cache_entry, cache);
+  
+  g_hash_table_destroy (cache->forward);
+  g_hash_table_destroy (cache->back);
+
+  g_list_free (cache->mru);
+}
+
+/**
+ * pango_x_font_cache_new:
+ * @display: an X display.
+ * 
+ * Create a font cache for the specified display.
+ * 
+ * Return value: The new font cache. This must be freed with
+ * pango_x_font_cache_free().
+ **/
+PangoXFontCache *
+pango_x_font_cache_new (Display *display)
+{
+  PangoXFontCache *cache;
+
+  g_return_val_if_fail (display != NULL, NULL);
+  
+  cache = g_new (PangoXFontCache, 1);
+
+  cache->display = display;
+  
+  cache->forward = g_hash_table_new (g_str_hash, g_str_equal);
+  cache->back = g_hash_table_new (g_direct_hash, g_direct_equal);
+      
+  cache->mru = NULL;
+  cache->mru_tail = NULL;
+  cache->mru_count = 0;
+  
+  return cache;
+}
+
+static void
+cache_entry_unref (PangoXFontCache *cache, CacheEntry *entry)
+{
+  entry->ref_count--;
+  if (entry->ref_count == 0)
+    {
+      g_hash_table_remove (cache->forward, entry->xlfd);
+      g_hash_table_remove (cache->back, entry->fs);
+
+      free_cache_entry (NULL, entry, cache);
+    }
+}
+
+/**
+ * pango_x_font_cache_load:
+ * @cache: a #PangoXFontCache
+ * @xlfd: the X Logical Font Description to load.
+ * 
+ * Load a #XFontStruct from a X Logical Font Description. The
+ * result may be newly loaded, or it may have been previously
+ * stored
+ * 
+ * Return value: The font structure, or %NULL if the font could
+ * not be loaded. In order to free this structure, you must call
+ * pango_x_font_cache_unload().
+ **/
+XFontStruct *
+pango_x_font_cache_load (PangoXFontCache *cache,
+			 char            *xlfd)
+{
+  CacheEntry *entry;
+
+  g_return_val_if_fail (cache != NULL, NULL);
+  g_return_val_if_fail (xlfd != NULL, NULL);
+
+  entry = g_hash_table_lookup (cache->forward, xlfd);
+
+  if (entry)
+    {
+      entry->ref_count++;
+    }
+  else
+    {
+      XFontStruct *fs = XLoadQueryFont (cache->display, xlfd);
+
+      if (!fs)
+	return NULL;
+      
+      entry = g_new (CacheEntry, 1);
+
+      entry->xlfd = g_strdup (xlfd);
+      entry->fs = fs;
+
+      entry->ref_count = 1;
+      entry->mru = NULL;
+
+      g_hash_table_insert (cache->forward, entry->xlfd, entry);
+      g_hash_table_insert (cache->back, entry->fs, entry); 
+    }
+  
+  if (entry->mru)
+    {
+      if (cache->mru_count > 1 && entry->mru->prev)
+	{
+	  /* Move to the head of the mru list */
+	  
+	  if (entry->mru == cache->mru_tail)
+	    {
+	      cache->mru_tail = cache->mru_tail->prev;
+	      cache->mru_tail->next = NULL;
+	    }
+	  else
+	    {
+	      entry->mru->prev->next = entry->mru->next;
+	      entry->mru->next->prev = entry->mru->prev;
+	    }
+	  
+	  entry->mru->next = cache->mru;
+	  entry->mru->prev = NULL;
+	  cache->mru = entry->mru;
+	}
+    }
+  else
+    {
+      entry->ref_count++;
+      
+      /* Insert into the mru list */
+      
+      if (cache->mru_count == CACHE_SIZE)
+	{
+	  CacheEntry *old_entry = cache->mru_tail->data;
+	  
+	  cache->mru_tail = cache->mru_tail->prev;
+	  cache->mru_tail->next = NULL;
+
+	  g_list_free_1 (old_entry->mru);
+	  old_entry->mru = NULL;
+	  cache_entry_unref (cache, old_entry);
+	}
+      else
+	cache->mru_count++;
+      
+      cache->mru = g_list_prepend (cache->mru, entry);
+      entry->mru = cache->mru;
+    }
+
+  return entry->fs;
+}
+
+/**
+ * pango_x_font_cache_unload:
+ * @cache: a #PangoXFontCache
+ * @fs: the font structure to unload
+ * 
+ * Free a font structure previously loaded with pango_x_font_cache_load()
+ **/
+void
+pango_x_font_cache_unload (PangoXFontCache *cache,
+			   XFontStruct     *fs)
+{
+  CacheEntry *entry;
+
+  g_return_if_fail (cache != NULL);
+  g_return_if_fail (fs != NULL);
+
+  entry = g_hash_table_lookup (cache->forward, fs);
+  g_return_if_fail (entry != NULL);
+
+  cache_entry_unref (cache, entry);  
+}