gecko-dev/gfx/cairo/win32-gdi-font-cache-no-HFONT.patch

# HG changeset patch
# User Robert O'Callahan <robert@ocallahan.org>
# Date 1357107533 -46800
# Node ID ed54dfdd2facb11a4d4158138b460a31de45e9f7
# Parent ab6457cc16ec14ea07386dcfc57cad6b8a9ac55d
Bug 717178. Part 3 alternative: don't put Win32 cairo_font_face_ts into the font-face cache if they were created with an explicit HFONT. r=jrmuizel

diff --git a/gfx/cairo/cairo/src/cairo-win32-font.c b/gfx/cairo/cairo/src/cairo-win32-font.c
--- a/gfx/cairo/cairo/src/cairo-win32-font.c
+++ b/gfx/cairo/cairo/src/cairo-win32-font.c
@@ -1941,16 +1942,21 @@ const cairo_font_face_backend_t _cairo_w
  * The primary purpose of this mapping is to provide unique
  * #cairo_font_face_t values so that our cache and mapping from
  * #cairo_font_face_t => #cairo_scaled_font_t works. Once the
  * corresponding #cairo_font_face_t objects fall out of downstream
  * caches, we don't need them in this hash table anymore.
  *
  * Modifications to this hash table are protected by
  * _cairo_win32_font_face_mutex.
+ *
+ * Only #cairo_font_face_t values with null 'hfont' (no
+ * HFONT preallocated by caller) are stored in this table. We rely
+ * on callers to manage the lifetime of the HFONT, and they can't
+ * do that if we share #cairo_font_face_t values with other callers.
  */
 
 static cairo_hash_table_t *cairo_win32_font_face_hash_table = NULL;
 
 static int
 _cairo_win32_font_face_keys_equal (const void *key_a,
 				   const void *key_b);
 
@@ -2036,22 +2042,24 @@ static int
 }
 
 static void
 _cairo_win32_font_face_destroy (void *abstract_face)
 {
     cairo_hash_table_t *hash_table;
     cairo_win32_font_face_t *font_face = abstract_face;
 
-    hash_table = _cairo_win32_font_face_hash_table_lock ();
-    if (unlikely (hash_table == NULL)) {
-        return;
+    if (!font_face->hfont) {
+        hash_table = _cairo_win32_font_face_hash_table_lock ();
+        if (unlikely (hash_table == NULL)) {
+            return;
+        }
+        _cairo_hash_table_remove (hash_table, &font_face->base.hash_entry);
+        _cairo_win32_font_face_hash_table_unlock ();
     }
-    _cairo_hash_table_remove (hash_table, &font_face->base.hash_entry);
-    _cairo_win32_font_face_hash_table_unlock ();
 }
 
 /**
  * cairo_win32_font_face_create_for_logfontw_hfont:
  * @logfont: A #LOGFONTW structure specifying the font to use.
  *   If @font is %NULL then the lfHeight, lfWidth, lfOrientation and lfEscapement
  *   fields of this structure are ignored. Otherwise lfWidth, lfOrientation and
  *   lfEscapement must be zero.
@@ -2070,55 +2078,63 @@ static void
  **/
 cairo_font_face_t *
 cairo_win32_font_face_create_for_logfontw_hfont (LOGFONTW *logfont, HFONT font)
 {
     cairo_win32_font_face_t *font_face, key;
     cairo_hash_table_t *hash_table;
     cairo_status_t status;
 
-    hash_table = _cairo_win32_font_face_hash_table_lock ();
-    if (unlikely (hash_table == NULL)) {
-        _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
-	return (cairo_font_face_t *)&_cairo_font_face_nil;
-    }
+    if (!font) {
+        hash_table = _cairo_win32_font_face_hash_table_lock ();
+        if (unlikely (hash_table == NULL)) {
+            _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
+	    return (cairo_font_face_t *)&_cairo_font_face_nil;
+        }
 
-    _cairo_win32_font_face_init_key (&key, logfont, font);
+        _cairo_win32_font_face_init_key (&key, logfont, font);
 
-    /* Return existing unscaled font if it exists in the hash table. */
-    font_face = _cairo_hash_table_lookup (hash_table,
-					 &key.base.hash_entry);
-    if (font_face != NULL) {
-	cairo_font_face_reference (&font_face->base);
-	goto DONE;
+        /* Return existing unscaled font if it exists in the hash table. */
+        font_face = _cairo_hash_table_lookup (hash_table,
+                                              &key.base.hash_entry);
+        if (font_face != NULL) {
+	    cairo_font_face_reference (&font_face->base);
+	    goto DONE;
+        }
     }
 
     /* Otherwise create it and insert into hash table. */
     font_face = malloc (sizeof (cairo_win32_font_face_t));
     if (!font_face) {
         _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
 	goto FAIL;
     }
 
     _cairo_win32_font_face_init_key (font_face, logfont, font);
     _cairo_font_face_init (&font_face->base, &_cairo_win32_font_face_backend);
+    assert (font_face->base.hash_entry.hash == key.base.hash_entry.hash);
 
-    assert (font_face->base.hash_entry.hash == key.base.hash_entry.hash);
-    status = _cairo_hash_table_insert (hash_table,
-				       &font_face->base.hash_entry);
-    if (unlikely (status))
-	goto FAIL;
+    if (!font) {
+        status = _cairo_hash_table_insert (hash_table,
+                                           &font_face->base.hash_entry);
+        if (unlikely (status))
+	    goto FAIL;
+    }
 
 DONE:
-    _cairo_win32_font_face_hash_table_unlock ();
+    if (!font) {
+        _cairo_win32_font_face_hash_table_unlock ();
+    }
 
     return &font_face->base;
 
 FAIL:
-    _cairo_win32_font_face_hash_table_unlock ();
+    if (!font) {
+        _cairo_win32_font_face_hash_table_unlock ();
+    }
 
     return (cairo_font_face_t *)&_cairo_font_face_nil;
 }
 
 /**
  * cairo_win32_font_face_create_for_logfontw:
  * @logfont: A #LOGFONTW structure specifying the font to use.
  *   The lfHeight, lfWidth, lfOrientation and lfEscapement