Validate MessageHeader before using

mojo/public/c/test_support/test_support.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MOJO_PUBLIC_C_TEST_SUPPORT_TEST_SUPPORT_H_
 #define MOJO_PUBLIC_C_TEST_SUPPORT_TEST_SUPPORT_H_
 
 // Note: This header should be compilable as C.
 
+#include <stdio.h>
+
 #include "mojo/public/c/test_support/test_support_export.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 MOJO_TEST_SUPPORT_EXPORT void MojoTestSupportLogPerfResult(
     const char* test_name,
     double value,
     const char* units);
 
+// Opens a "/"-delimited file path relative to the source root.
+MOJO_TEST_SUPPORT_EXPORT FILE* MojoTestSupportOpenSourceRootRelativeFile(
+    const char* source_root_relative_path);
+
+// Enumerates a "/"-delimited directory path relative to the source root.
+// Returns only regular files. The return value is a heap-allocated array of
+// heap-allocated strings. Each must be free'd separately.
+//
+// The return value is built like so:
+//
+//   char** rv = (char**) calloc(N + 1, sizeof(char*));
+//   rv[0] = strdup("a");
+//   rv[1] = strdup("b");
+//   rv[2] = strdup("c");
+//   ...
+//   rv[N] = NULL;
+//
+MOJO_TEST_SUPPORT_EXPORT
+char** MojoTestSupportEnumerateSourceRootRelativeDirectory(
+    const char* source_root_relative_path);
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif
 
 #endif  // MOJO_PUBLIC_C_TEST_SUPPORT_TEST_SUPPORT_H_