Modify loader VK_ADD_DRIVER_FILES behavior

Modify the loader to only use VK_ADD_DRIVER_FILES if
VK_DRIVER_FILES or VK_ICD_FILENAMES is not used.
This could have caused weird issues with systems where VK_DRIVER_FILES
was used to force drivers in a specific order/location for testing.

Resolves issue #871

diff --git a/docs/LoaderDriverInterface.md b/docs/LoaderDriverInterface.md
index d27efeb2078b017fbef9854fd2c4ba133c655ebf..525b2457a83c791f63bfbf13c60a6cf36ca96a49 100644 (file)
--- a/docs/LoaderDriverInterface.md
+++ b/docs/LoaderDriverInterface.md
@@ -125,6 +125,9 @@ Driver Manifest files, containing the full path to the driver JSON Manifest file
 This list is colon-separated on Linux and macOS, and semicolon-separated on
 Windows.
 It will be added prior to the standard driver search files.
+If `VK_DRIVER_FILES` or `VK_ICD_FILENAMES` is present, then
+`VK_ADD_DRIVER_FILES` will not be used by the loader and any values will be
+ignored.
 
 #### Exception for Elevated Privileges
 

diff --git a/docs/LoaderLayerInterface.md b/docs/LoaderLayerInterface.md
index 48b0ee1b8db40f7894c191411b7aa4fd90aa1fad..7d8d2b73bfba69f084ae8380bb76e0f28f057594 100644 (file)
--- a/docs/LoaderLayerInterface.md
+++ b/docs/LoaderLayerInterface.md
@@ -237,6 +237,9 @@ provided by the explicit layer registry keys.
 The paths provided by `VK_ADD_LAYER_PATH` are added before the standard list
 of search folders and will therefore be searched first.
 
+If `VK_LAYER_PATH` is present, then `VK_ADD_LAYER_PATH` will not be used by the
+loader and any values will be ignored.
+
 For security reasons, both `VK_LAYER_PATH` and `VK_ADD_LAYER_PATH` are ignored
 if running with elevated privileges.
 See [Exception for Elevated Privileges](#exception-for-elevated-privileges)

diff --git a/loader/loader.c b/loader/loader.c
index 49a211564004f78eb19e884e8954cd392ead08cc..4fef9c720956678c024742564157bb5a8e84d1ef 100644 (file)
--- a/loader/loader.c
+++ b/loader/loader.c
@@ -3002,7 +3002,6 @@ static VkResult read_data_files_in_search_paths(const struct loader_instance *in
                 override_env = loader_secure_getenv(VK_ICD_FILENAMES_ENV_VAR, inst);
             }
             additional_env = loader_secure_getenv(VK_ADDITIONAL_DRIVER_FILES_ENV_VAR, inst);
-            additional_env = loader_secure_getenv(VK_ADDITIONAL_DRIVER_FILES_ENV_VAR, inst);
             relative_location = VK_DRIVERS_INFO_RELATIVE_DIR;
             break;
         case LOADER_DATA_FILE_MANIFEST_IMPLICIT_LAYER:
@@ -3031,15 +3030,6 @@ static VkResult read_data_files_in_search_paths(const struct loader_instance *in
     if (NULL != override_path) {
         // Local folder and null terminator
         search_path_size += strlen(override_path) + 2;
-
-        // Add the size of any additional search paths defined in the additive environment variable
-        if (NULL != additional_env) {
-            search_path_size += determine_data_file_path_size(additional_env, 0) + 2;
-        }
-    } else if (NULL == relative_location) {
-        // If there's no override, and no relative location, bail out.  This is usually
-        // the case when we're on Windows and the default path is to use the registry.
-        goto out;
     } else {
         // Add the size of any additional search paths defined in the additive environment variable
         if (NULL != additional_env) {
@@ -3091,18 +3081,6 @@ static VkResult read_data_files_in_search_paths(const struct loader_instance *in
     if (NULL != override_path) {
         strcpy(cur_path_ptr, override_path);
         cur_path_ptr += strlen(override_path);
-        if (NULL != additional_env) {
-            *cur_path_ptr++ = PATH_SEPARATOR;
-
-            copy_data_file_info(additional_env, NULL, 0, &cur_path_ptr);
-
-            // Remove the last path separator
-            *cur_path_ptr = '\0';
-            if (search_path[strlen(search_path) - 1] == ':') {
-                --cur_path_ptr;
-                *cur_path_ptr = '\0';
-            }
-        }
     } else {
         // Add any additional search paths defined in the additive environment variable
         if (NULL != additional_env) {