loader: Expand lib search locations

Expand library search locations based on recommendations by
Dustin.  We still attempt to use the old LoadLibrary first,
and then, only if that fails, do we attempt to use the new search.

Change-Id: I4cf1358f9eb7e45ac61f36435e926aa89c212f83

1 files changed, 9 insertions, 1 deletions

diff --git a/loader/vk_loader_platform.h b/loader/vk_loader_platform.h
index 0f71d9a3..8b82fe80 100644
--- a/loader/vk_loader_platform.h
+++ b/loader/vk_loader_platform.h
@@ -242,7 +242,15 @@ static char *loader_platform_basename(char *pathname) {
 
 // Dynamic Loading:
 typedef HMODULE loader_platform_dl_handle;
-static loader_platform_dl_handle loader_platform_open_library(const char *libPath) { return LoadLibrary(libPath); }
+static loader_platform_dl_handle loader_platform_open_library(const char *lib_path) {
+    // Try loading the library the original way first.
+    loader_platform_dl_handle lib_handle = LoadLibrary(lib_path);
+    if (lib_handle == NULL && GetLastError() == ERROR_MOD_NOT_FOUND && PathFileExists(lib_path)) {
+        // If that failed, then try loading it with broarder search folders.
+        lib_handle = LoadLibraryEx(lib_path, NULL, LOAD_LIBRARY_SEARCH_DEFAULT_DIRS | LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR);
+    }
+    return lib_handle;
+}
 static char *loader_platform_open_library_error(const char *libPath) {
     static char errorMsg[164];
     (void)snprintf(errorMsg, 163, "Failed to open dynamic library \"%s\"", libPath);