dump_util: richer StdioFile type

src/util/dump_util.h

@@ -29,6 +29,8 @@
 #ifndef DUMP_UTIL
 #define DUMP_UTIL
 
+#include "noncopyable.h"
+
 #include <cstdio>
 #include <memory>
 #include <string>
@@ -41,18 +43,20 @@ namespace ue2 {
 FILE *fopen_or_throw(const char *path, const char *mode);
 
 /**
- * \brief Helper function: returns a C stdio FILE* handle wrapped in
- * a unique_ptr that takes care of closing the file on destruction.
- *
- * If the file cannot be opened, throws an exception.
+ * \brief Helper class: wraps C stdio FILE* handle and takes care of closing
+ * the file on destruction.
  */
-inline
-std::unique_ptr<FILE, decltype(&fclose)>
-openStdioFile(const std::string &filename, const char *mode) {
-    return std::unique_ptr<FILE, decltype(&fclose)>(
-        fopen_or_throw(filename.c_str(), mode), &fclose);
-}
+class StdioFile : noncopyable {
+public:
+    StdioFile(const std::string &filename, const char *mode)
+        : handle(fopen_or_throw(filename.c_str(), mode), &fclose) {}
 
+    // Implicit conversion to FILE* for use by stdio calls.
+    operator FILE *() { return handle.get(); }
+
+private:
+    std::unique_ptr<FILE, decltype(&fclose)> handle;
+};
 
 } // namespace ue2