Make all the files mapped in when running base_unittests read only.

base/file_util_win.cc

 // Copyright (c) 2012 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.
 
 #include "base/file_util.h"
 
 #include <windows.h>
 #include <psapi.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 710 matching lines @@
 
 bool CopyFileUnsafe(const FilePath& from_path, const FilePath& to_path) {
   ThreadRestrictions::AssertIOAllowed();
 
   // NOTE: I suspect we could support longer paths, but that would involve
   // analyzing all our usage of files.
   if (from_path.value().length() >= MAX_PATH ||
       to_path.value().length() >= MAX_PATH) {
     return false;
   }
-  return (::CopyFile(from_path.value().c_str(), to_path.value().c_str(),
-                     false) != 0);
+
+  // Unlike the posix implementation that copies the file manually and discards
+  // the ACL bits, CopyFile() copies the complete SECURITY_DESCRIPTOR and access
+  // bits, which is usually not what we want. We can't do much about the
+  // SECURITY_DESCRIPTOR but at least remove the read only bit.
+  const wchar_t* dest = to_path.value().c_str();
+  if (0 == ::CopyFile(from_path.value().c_str(), dest, false)) {

[Nico, 2014/01/14 02:30:33]

nit: `::CopyFile(...) == 0`; no yoda conditions in chrome

[M-A Ruel, 2014/01/14 14:59:39]

Done.

+    // Copy failed.
+    return false;
+  }
+  DWORD attrs = GetFileAttributes(dest);
+  if (attrs==INVALID_FILE_ATTRIBUTES) {

[Nico, 2014/01/14 02:30:33]

nit: spaces around ==

[M-A Ruel, 2014/01/14 14:59:39]

Done.

+    return false;
+  }
+  if (attrs & FILE_ATTRIBUTE_READONLY) {
+    SetFileAttributes(dest, attrs & ~FILE_ATTRIBUTE_READONLY);
+  }
+  return true;
 }
 
 bool CopyAndDeleteDirectory(const FilePath& from_path,
                             const FilePath& to_path) {
   ThreadRestrictions::AssertIOAllowed();
   if (CopyDirectory(from_path, to_path, true)) {
     if (DeleteFile(from_path, true))
       return true;
 
     // Like Move, this function is not transactional, so we just
     // leave the copied bits behind if deleting from_path fails.
     // If to_path exists previously then we have already overwritten
     // it by now, we don't get better off by deleting the new bits.
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace base