Add a "noop" implementation.

This new implementation is ahead of all other implementations in the
fallback chain and is supposed to contain operations that are "noops",
ie., they don't require any work. For example, it might contain a
"fast path" for the DST operator that doesn't actually do anything or
an iterator for a8r8g8b8 that just returns a pointer into the image.

4 files changed, 51 insertions, 0 deletions

diff --git a/pixman/Makefile.am b/pixman/Makefile.am
index be08266..1e20bb0 100644
--- a/pixman/Makefile.am
+++ b/pixman/Makefile.am
@@ -20,6 +20,7 @@ libpixman_1_la_SOURCES =			\
 	pixman-combine64.h			\
 	pixman-general.c			\
 	pixman.c				\
+	pixman-noop.c				\
 	pixman-fast-path.c			\
 	pixman-fast-path.h			\
 	pixman-solid-fill.c			\
diff --git a/pixman/pixman-cpu.c b/pixman/pixman-cpu.c
index 0e14ecb..973ed54 100644
--- a/pixman/pixman-cpu.c
+++ b/pixman/pixman-cpu.c
@@ -606,6 +606,8 @@ _pixman_choose_implementation (void)
 	imp = _pixman_implementation_create_vmx (imp);
 #endif
 
+    imp = _pixman_implementation_create_noop (imp);
+    
     return imp;
 }
 
diff --git a/pixman/pixman-noop.c b/pixman/pixman-noop.c
new file mode 100644
index 0000000..50bbfb0
--- /dev/null
+++ b/pixman/pixman-noop.c
@@ -0,0 +1,45 @@
+/* -*- Mode: c; c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t; -*- */
+/*
+ * Copyright © 2011 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <string.h>
+#include <stdlib.h>
+#include "pixman-private.h"
+#include "pixman-combine32.h"
+#include "pixman-fast-path.h"
+
+static const pixman_fast_path_t noop_fast_paths[] =
+{
+    { PIXMAN_OP_NONE },
+};
+
+pixman_implementation_t *
+_pixman_implementation_create_noop (pixman_implementation_t *fallback)
+{
+    pixman_implementation_t *imp =
+	_pixman_implementation_create (fallback, noop_fast_paths);
+
+    return imp;
+}
diff --git a/pixman/pixman-private.h b/pixman/pixman-private.h
index 60060a9..2996907 100644
--- a/pixman/pixman-private.h
+++ b/pixman/pixman-private.h
@@ -523,6 +523,9 @@ _pixman_implementation_create_general (void);
 pixman_implementation_t *
 _pixman_implementation_create_fast_path (pixman_implementation_t *fallback);
 
+pixman_implementation_t *
+_pixman_implementation_create_noop (pixman_implementation_t *fallback);
+
 #ifdef USE_MMX
 pixman_implementation_t *
 _pixman_implementation_create_mmx (pixman_implementation_t *fallback);