loader: bug 12992: extension and layer support

Much of layers and loader updated to work with
final extension and layer mechanism.
Not everything is working here.
diff --git a/layers/vk_layer_extension_utils.cpp b/layers/vk_layer_extension_utils.cpp
new file mode 100644
index 0000000..71c3cba
--- /dev/null
+++ b/layers/vk_layer_extension_utils.cpp
@@ -0,0 +1,87 @@
+/*
+ * Vulkan
+ *
+ * Copyright (C) 2015 LunarG, 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 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.
+ *
+ * Authors:
+ *   Courtney Goeltzenleuchter <courtney@lunarg.com>
+ */
+
+#include "string.h"
+#include "vk_layer_extension_utils.h"
+
+/*
+ * This file contains utility functions for layers
+ */
+
+VkResult util_GetExtensionProperties(
+        const uint32_t count,
+        const VkExtensionProperties *layer_extensions,
+        uint32_t* pCount,
+        VkExtensionProperties* pProperties)
+{
+    uint32_t copy_size;
+
+    if (pCount == NULL) {
+        return VK_ERROR_INVALID_POINTER;
+    }
+
+    if (pProperties == NULL || layer_extensions == NULL) {
+        *pCount = count;
+        return VK_SUCCESS;
+    }
+
+    copy_size = *pCount < count ? *pCount : count;
+    memcpy(pProperties, layer_extensions, copy_size * sizeof(VkExtensionProperties));
+    *pCount = copy_size;
+    if (copy_size < count) {
+        return VK_INCOMPLETE;
+    }
+
+    return VK_SUCCESS;
+}
+
+VkResult util_GetLayerProperties(
+        const uint32_t count,
+        const VkLayerProperties *layer_properties,
+        uint32_t* pCount,
+        VkLayerProperties* pProperties)
+{
+    uint32_t copy_size;
+
+    if (pCount == NULL) {
+        return VK_ERROR_INVALID_POINTER;
+    }
+
+    if (pProperties == NULL || layer_properties == NULL) {
+        *pCount = count;
+        return VK_SUCCESS;
+    }
+
+    copy_size = *pCount < count ? *pCount : count;
+    memcpy(pProperties, layer_properties, copy_size * sizeof(VkLayerProperties));
+    *pCount = copy_size;
+    if (copy_size < count) {
+        return VK_INCOMPLETE;
+    }
+
+    return VK_SUCCESS;
+}