Log when Filter Env-Vars act when settings file is active

The logging to indicate that VK_LOADER_LAYERS_ENABLE and VK_LOADER_LAYERS_DISABLE
turned on/off layers was not occuring when the settings file was active. This
is due to layer enablement being done in `enable_correct_layers_from_settings()`,
a newer function. which lacked the log functions.
This commit rectifies the lack of logging in the new function.

Author: charles-lunarg

loader/settings.c

@@ -767,6 +767,11 @@ VkResult enable_correct_layers_from_settings(const struct loader_instance* inst,
         bool enable_layer = false;
         struct loader_layer_properties* props = &instance_layers->list[i];
 
+        // Skip the sentinel unordered layer location
+        if (props->settings_control_value == LOADER_SETTINGS_LAYER_UNORDERED_LAYER_LOCATION) {
+            continue;
+        }
+
         // Do not enable the layer if the settings have it set as off
         if (props->settings_control_value == LOADER_SETTINGS_LAYER_CONTROL_OFF) {
             continue;
@@ -780,13 +785,20 @@ VkResult enable_correct_layers_from_settings(const struct loader_instance* inst,
             if ((filters->disable_filter.disable_all || filters->disable_filter.disable_all_implicit ||
                  check_name_matches_filter_environment_var(props->info.layerName, &filters->disable_filter.additional_filters)) &&
                 !check_name_matches_filter_environment_var(props->info.layerName, &filters->allow_filter)) {
+                // Report a message that we've forced off a layer if it would have been enabled normally.
+                loader_log(inst, VULKAN_LOADER_WARN_BIT | VULKAN_LOADER_LAYER_BIT, 0,
+                           "Layer \"%s\" forced disabled because name matches filter of env var \'%s\'.", props->info.layerName,
+                           VK_LAYERS_DISABLE_ENV_VAR);
+
                 continue;
             }
         }
         // Check the enable filter
         if (!enable_layer && check_name_matches_filter_environment_var(props->info.layerName, &filters->enable_filter)) {
             enable_layer = true;
             props->enabled_by_what = ENABLED_BY_WHAT_VK_LOADER_LAYERS_ENABLE;
+            loader_log(inst, VULKAN_LOADER_WARN_BIT | VULKAN_LOADER_LAYER_BIT, 0,
+                       "Layer \"%s\" forced enabled due to env var \'%s\'.", props->info.layerName, VK_LAYERS_ENABLE_ENV_VAR);
         }
 
         // First look for the old-fashion layers forced on with VK_INSTANCE_LAYERS

tests/loader_settings_tests.cpp

@@ -2910,7 +2910,10 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(3).layerName, env_var_implicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log(
+            "env var 'VK_INSTANCE_LAYERS' defined and adding layers: VK_LAYER_regular_explicit_layer"));
     }
+    env.platform_shim->clear_logs();
     {  // VK_LOADER_LAYERS_ENABLE
         EnvVarWrapper env_var_enable{"VK_LOADER_LAYERS_ENABLE", regular_explicit_layer};
         InstWrapper inst{env.vulkan_functions};
@@ -2920,14 +2923,22 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(3).layerName, env_var_implicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log(
+            "Layer \"VK_LAYER_regular_explicit_layer\" forced enabled due to env var 'VK_LOADER_LAYERS_ENABLE'"));
     }
+    env.platform_shim->clear_logs();
     {                                                                        // VK_LOADER_LAYERS_DISABLE
         EnvVarWrapper env_var_disable{"VK_LOADER_LAYERS_DISABLE", "~all~"};  // ignored by settings file
         InstWrapper inst{env.vulkan_functions};
         inst.CheckCreate();
         auto layers = inst.GetActiveLayers(inst.GetPhysDev(), 1);
         EXPECT_TRUE(string_eq(layers.at(0).layerName, regular_explicit_layer_settings_file_set_on));
+        EXPECT_TRUE(
+            env.platform_shim->find_in_log("Layer \"VK_LAYER_env_var_implicit_layer\" forced disabled because name matches filter "
+                                           "of env var 'VK_LOADER_LAYERS_DISABLE'"));
     }
+    env.platform_shim->clear_logs();
+
     {  // VK_LOADER_LAYERS_ALLOW
         EnvVarWrapper env_var_allow{"VK_LOADER_LAYERS_ALLOW", regular_implicit_layer};
         // Allow only makes sense when the disable env-var is also set
@@ -2939,7 +2950,13 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         // The regular_implicit_layer is set to "auto" so is affected by environment variables
         EXPECT_TRUE(string_eq(layers.at(0).layerName, regular_implicit_layer));
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer_settings_file_set_on));
+
+        EXPECT_TRUE(
+            env.platform_shim->find_in_log("Layer \"VK_LAYER_env_var_implicit_layer\" forced disabled because name matches filter "
+                                           "of env var 'VK_LOADER_LAYERS_DISABLE'"));
     }
+    env.platform_shim->clear_logs();
+
     {  // VK_LAYER_PATH
         // VK_LAYER_PATH is set by add_explicit_layer()
         InstWrapper inst{env.vulkan_functions};
@@ -2950,7 +2967,9 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, env_var_implicit_layer));
         EXPECT_TRUE(string_eq(layers.at(3).layerName, env_var_explicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log("Insert instance layer \"VK_LAYER_env_var_explicit_layer\""));
     }
+    env.platform_shim->clear_logs();
     {  // VK_IMPLICIT_LAYER_PATH
         // VK_IMPLICIT_LAYER_PATH is set by add_implicit_layer()
         InstWrapper inst{env.vulkan_functions};
@@ -2959,7 +2978,9 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(0).layerName, regular_implicit_layer));
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, env_var_implicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log("Insert instance layer \"VK_LAYER_env_var_implicit_layer\""));
     }
+    env.platform_shim->clear_logs();
     {  // VK_ADD_LAYER_PATH
         // VK_ADD_LAYER_PATH is set by add_explicit_layer(), but we need to disable VK_LAYER_PATH
         // since VK_LAYER_PATH overrides VK_ADD_LAYER_PATH
@@ -2973,7 +2994,9 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, env_var_implicit_layer));
         EXPECT_TRUE(string_eq(layers.at(3).layerName, add_env_var_explicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log("Insert instance layer \"VK_LAYER_add_env_var_explicit_layer\""));
     }
+    env.platform_shim->clear_logs();
     {  // VK_ADD_IMPLICIT_LAYER_PATH
         // VK_ADD_IMPLICIT_LAYER_PATH is set by add_explicit_layer(), but we need to disable VK_LAYER_PATH
         // since VK_IMPLICIT_LAYER_PATH overrides VK_ADD_IMPLICIT_LAYER_PATH
@@ -2985,5 +3008,6 @@ TEST(SettingsFile, EnvVarsWorkTogether) {
         EXPECT_TRUE(string_eq(layers.at(0).layerName, regular_implicit_layer));
         EXPECT_TRUE(string_eq(layers.at(1).layerName, regular_explicit_layer_settings_file_set_on));
         EXPECT_TRUE(string_eq(layers.at(2).layerName, add_env_var_implicit_layer));
+        EXPECT_TRUE(env.platform_shim->find_in_log("Insert instance layer \"VK_LAYER_add_env_var_implicit_layer\""));
     }
 }