util/lib.c: Add module file path utility

util/lib.c

@@ -0,0 +1,29 @@
+#include <windows.h>
+
+#include <stdbool.h>
+
+wchar_t *module_file_name(HMODULE module)
+{
+    size_t buf_len;
+    DWORD len;
+    wchar_t *buf;
+
+    buf_len = MAX_PATH;
+    buf = malloc(buf_len * sizeof(*buf));
+
+    while (true) {
+        len = GetModuleFileNameW(module, buf, buf_len);
+
+        if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) {
+            buf_len = len;
+            buf = realloc(buf, buf_len * sizeof(*buf));
+
+            break;
+        }
+
+        buf_len *= 2;
+        buf = realloc(buf, buf_len * sizeof(*buf));
+    }
+
+    return buf;
+}