Allow NULL as a valid value for several objects. That is, calling reference or destroy on these objects will simply do nothing, successfully.

Remove extra whitespace.

ChangeLog

@@ -4,6 +4,26 @@
 	the clip surface to a new surface the size of the intersection of
 	the old clip surface and the extents of the new clip path.
 
+2005-06-03  Carl Worth  <cworth@cworth.org>
+
+	* src/cairo-font.c: (cairo_font_face_reference),
+	(cairo_font_face_destroy), (_cairo_simple_font_face_destroy),
+	(_cairo_unscaled_font_reference), (_cairo_unscaled_font_destroy),
+	(cairo_scaled_font_reference), (cairo_scaled_font_destroy):
+	* src/cairo-ft-font.c: (_ft_font_cache_destroy_cache),
+	(_cairo_ft_unscaled_font_destroy), (_ft_font_face_destroy):
+	* src/cairo-glitz-surface.c: (_cairo_glitz_area_destroy):
+	* src/cairo-path-data.c: (cairo_path_destroy):
+	* src/cairo-pdf-surface.c: (cairo_pdf_font_destroy),
+	(cairo_pdf_ft_font_destroy):
+	* src/cairo-win32-font.c: (_cairo_win32_scaled_font_destroy):
+	Allow NULL as a valid value for several objects. That is, calling
+	reference or destroy on these objects will simply do nothing,
+	successfully.
+
+	* src/cairo-atsui-font.c: (_cairo_atsui_font_destroy_font): Remove
+	extra whitespace.
+
 2005-06-03  Carl Worth  <cworth@cworth.org>
 
 	* src/cairoint.h:

src/cairo-atsui-font.c

@@ -209,7 +209,6 @@ _cairo_atsui_font_destroy_font(void *abstract_font)
 {
     cairo_atsui_font_t *font = abstract_font;
 
-
     if (font == NULL)
         return;
 

src/cairo-font.c

@@ -53,15 +53,19 @@ _cairo_font_face_init (cairo_font_face_t               *font_face,
 
 /**
  * cairo_font_face_reference:
- * @font_face: a #cairo_font_face_t
+ * @font_face: a #cairo_font_face_t, (may be NULL in which case this
+ * function does nothing).
  * 
  * Increases the reference count on @font_face by one. This prevents
- * @font_face from being destroyed until a matching call to cairo_font_face_destroy() 
- * is made.
+ * @font_face from being destroyed until a matching call to
+ * cairo_font_face_destroy() is made.
  **/
 void
 cairo_font_face_reference (cairo_font_face_t *font_face)
 {
+    if (font_face == NULL)
+	return;
+
     font_face->refcount++;
 }
 
@@ -76,6 +80,9 @@ cairo_font_face_reference (cairo_font_face_t *font_face)
 void
 cairo_font_face_destroy (cairo_font_face_t *font_face)
 {
+    if (font_face == NULL)
+	return;
+
     if (--(font_face->refcount) > 0)
 	return;
 
@@ -327,6 +334,9 @@ _cairo_simple_font_face_destroy (void *abstract_face)
     cairo_cache_t *cache;
     cairo_simple_cache_key_t key;
 
+    if (simple_face == NULL)
+	return;
+
     _lock_global_simple_cache ();
     cache = _get_global_simple_cache ();
     assert (cache);
@@ -847,12 +857,18 @@ _cairo_unscaled_font_init (cairo_unscaled_font_t               *unscaled_font,
 void
 _cairo_unscaled_font_reference (cairo_unscaled_font_t *unscaled_font)
 {
+    if (unscaled_font == NULL)
+	return;
+
     unscaled_font->refcount++;
 }
 
 void
 _cairo_unscaled_font_destroy (cairo_unscaled_font_t *unscaled_font)
 {    
+    if (unscaled_font == NULL)
+	return;
+
     if (--(unscaled_font->refcount) > 0)
 	return;
 
@@ -867,7 +883,8 @@ _cairo_unscaled_font_destroy (cairo_unscaled_font_t *unscaled_font)
 
 /**
  * cairo_scaled_font_reference:
- * @scaled_font: a #cairo_scaled_font_t
+ * @scaled_font: a #cairo_scaled_font_t, (may be NULL in which case
+ * this function does nothing)
  * 
  * Increases the reference count on @scaled_font by one. This prevents
  * @scaled_font from being destroyed until a matching call to
@@ -876,6 +893,9 @@ _cairo_unscaled_font_destroy (cairo_unscaled_font_t *unscaled_font)
 void
 cairo_scaled_font_reference (cairo_scaled_font_t *scaled_font)
 {
+    if (scaled_font == NULL)
+	return;
+
     scaled_font->refcount++;
 }
 
@@ -893,6 +913,9 @@ cairo_scaled_font_destroy (cairo_scaled_font_t *scaled_font)
     cairo_font_cache_key_t key;
     cairo_cache_t *cache;
 
+    if (scaled_font == NULL)
+	return;
+
     if (--(scaled_font->refcount) > 0)
 	return;
 

src/cairo-ft-font.c

@@ -256,6 +256,7 @@ static void
 _ft_font_cache_destroy_cache (void *cache)
 {
     ft_cache_t *fc = (ft_cache_t *) cache;
+
     FT_Done_FreeType (fc->lib);
     free (fc);
 }
@@ -482,6 +483,9 @@ _cairo_ft_unscaled_font_destroy (void *abstract_font)
 {
     ft_unscaled_font_t *unscaled  = abstract_font;
 
+    if (unscaled == NULL)
+	return;
+
     if (unscaled->from_face) {
 	/* See comments in _ft_font_face_destroy about the "zombie" state
 	 * for a _ft_font_face.
@@ -1340,6 +1344,9 @@ _ft_font_face_destroy (void *abstract_face)
     ft_font_face_t *tmp_face = NULL;
     ft_font_face_t *last_face = NULL;
 
+    if (font_face == NULL)
+	return;
+
     /* When destroying the face created by cairo_ft_font_face_create_for_ft_face,
      * we have a special "zombie" state for the face when the unscaled font
      * is still alive but there are no public references to the font face.

src/cairo-glitz-surface.c

@@ -1328,7 +1328,7 @@ _cairo_glitz_area_create (cairo_glitz_root_area_t *root,
 static void
 _cairo_glitz_area_destroy (cairo_glitz_area_t *area)
 {   
-    if (!area)
+    if (area == NULL)
 	return;
 
     if (area->state == CAIRO_GLITZ_AREA_OCCUPIED)

src/cairo-path-data.c

@@ -364,9 +364,26 @@ _cairo_path_data_create_real (cairo_path_fixed_t *path_fixed,
     return path;
 }
 
+/**
+ * cairo_path_destroy:
+ * @path: a #cairo_path_t pointer returned from either cairo_copy_path
+ * or cairo_copy_path_flat.
+ * 
+ * Frees @path and all memory associated with it. Upon returning from
+ * this function @path will be pointing to an invalid location which
+ * should not be used.
+ *
+ * The cairo_path_destroy function should only be called with a
+ * pointer to a #cairo_path_t returned by a cairo function. Any
+ * manually created cairo_path_t object should be freed manually as
+ * well.
+ **/
 void
 cairo_path_destroy (cairo_path_t *path)
 {
+    if (path == NULL)
+	return;
+
     free (path->data);
     path->num_data = 0;
     free (path);

src/cairo-pdf-surface.c

@@ -291,6 +291,9 @@ cairo_pdf_font_generate (cairo_pdf_font_t *font,
 static void
 cairo_pdf_font_destroy (cairo_pdf_font_t *font)
 {
+    if (font == NULL)
+	return;
+
     font->backend->destroy (font);
 }
 
@@ -378,6 +381,9 @@ cairo_pdf_ft_font_destroy (void *abstract_font)
 {
     cairo_pdf_ft_font_t *font = abstract_font;
 
+    if (font == NULL)
+	return;
+
     _cairo_unscaled_font_destroy (font->base.unscaled_font);
     free (font->base.base_font);
     free (font->parent_to_subset);

src/cairo-win32-font.c

@@ -466,6 +466,9 @@ _cairo_win32_scaled_font_destroy (void *abstract_font)
 {
     cairo_win32_scaled_font_t *scaled_font = abstract_font;
 
+    if (scaled_font == NULL)
+	return;
+
     if (scaled_font->scaled_hfont)
 	DeleteObject (scaled_font->scaled_hfont);