[Vulkan] Expose instance extensions from implicit layers.

Previously the vulkan loader only exposes instance extensions from the
driver implementation. Per vkEnumerateInstanceExtensionProperties spec
the loader must also advertise instance extensions from implicitly
enabled layers.

Bug: b/143293104
Test: vkEnumerateInstanceExtensionProperties returns the instance
extensions from implicit layers.

Change-Id: I17f4ce370bf5f4bba295165a28836e2b7c03a318

1 files changed, 62 insertions, 3 deletions

diff --git a/vulkan/libvulkan/api.cpp b/vulkan/libvulkan/api.cpp
index aae72db0fe..e607b058eb 100644
--- a/vulkan/libvulkan/api.cpp
+++ b/vulkan/libvulkan/api.cpp
@@ -29,6 +29,8 @@
 #include <algorithm>
 #include <mutex>
 #include <new>
+#include <string>
+#include <unordered_set>
 #include <utility>
 
 #include <android-base/strings.h>
@@ -1280,9 +1282,66 @@ VkResult EnumerateInstanceExtensionProperties(
         return *pPropertyCount < count ? VK_INCOMPLETE : VK_SUCCESS;
     }
 
-    // TODO(b/143293104): expose extensions from implicitly enabled layers
-    return vulkan::driver::EnumerateInstanceExtensionProperties(
-        nullptr, pPropertyCount, pProperties);
+    // If the pLayerName is nullptr, we must advertise all instance extensions
+    // from all implicitly enabled layers and the driver implementation. If
+    // there are duplicates among layers and the driver implementation, always
+    // only preserve the top layer closest to the application regardless of the
+    // spec version.
+    std::vector<VkExtensionProperties> properties;
+    std::unordered_set<std::string> extensionNames;
+
+    // Expose extensions from implicitly enabled layers.
+    const std::string layersSetting =
+        android::GraphicsEnv::getInstance().getDebugLayers();
+    if (!layersSetting.empty()) {
+        std::vector<std::string> layers =
+            android::base::Split(layersSetting, ":");
+        for (uint32_t i = 0; i < layers.size(); i++) {
+            const Layer* layer = FindLayer(layers[i].c_str());
+            if (!layer) {
+                continue;
+            }
+            uint32_t count = 0;
+            const VkExtensionProperties* props =
+                GetLayerInstanceExtensions(*layer, count);
+            if (count > 0) {
+                for (uint32_t i = 0; i < count; ++i) {
+                    if (extensionNames.emplace(props[i].extensionName).second) {
+                        properties.push_back(props[i]);
+                    }
+                }
+            }
+        }
+    }
+
+    // TODO(b/143293104): Parse debug.vulkan.layers properties
+
+    // Expose extensions from driver implementation.
+    {
+        uint32_t count = 0;
+        VkResult result = vulkan::driver::EnumerateInstanceExtensionProperties(
+            nullptr, &count, nullptr);
+        if (result == VK_SUCCESS && count > 0) {
+            std::vector<VkExtensionProperties> props(count);
+            result = vulkan::driver::EnumerateInstanceExtensionProperties(
+                nullptr, &count, props.data());
+            for (auto prop : props) {
+                if (extensionNames.emplace(prop.extensionName).second) {
+                    properties.push_back(prop);
+                }
+            }
+        }
+    }
+
+    uint32_t totalCount = properties.size();
+    if (!pProperties || *pPropertyCount > totalCount) {
+        *pPropertyCount = totalCount;
+    }
+    if (pProperties) {
+        std::copy(properties.data(), properties.data() + *pPropertyCount,
+                  pProperties);
+    }
+    return *pPropertyCount < totalCount ? VK_INCOMPLETE : VK_SUCCESS;
 }
 
 VkResult EnumerateDeviceLayerProperties(VkPhysicalDevice physicalDevice,