first cut: establishes base helper classes and main

platform_reader.cc

+// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Defines the PlatformReader base class.  By default, it will read an integer
+// from a file and assigned it to a PlatformValue which is
+// implementation-specific.
+
+#include "platform_reader.h"
+
+#include <sys/types.h>
+
+namespace cros_boot_mode {
+
+PlatformReader::PlatformReader() :
+  value_(kUnsupported), platform_file_path_(NULL) { }
+
+PlatformReader::~PlatformReader() { }
+
+const char *PlatformReader::platform_file_path() const {
+  if (platform_file_path_)
+    return platform_file_path_;
+  return default_platform_file_path();
+}
+
+void PlatformReader::Initialize() {
+  char *buf = new char[max_size() + 1];
+  size_t bytes_read = helpers::read_file(platform_file_path(),
+                                         buf,
+                                         max_size());
+  // read_file doesn't NUL-terminate.
+  buf[bytes_read] = '\0';
+  set_value(Process(buf, bytes_read));
+  delete [] buf;
+}
+
+}  // namespace cros_boot_mode