Modify fileAtPath stat to track if the call was redirected by chrome_elf.

chrome_elf/create_file/chrome_create_file.cc

 // 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.
 
 #include "chrome_elf/create_file/chrome_create_file.h"
 
 #include <string>
 
 #include "base/strings/string16.h"
 #include "chrome_elf/chrome_elf_constants.h"
@@ skipping 26 matching lines @@
   IN HANDLE token,
   IN DWORD flags,
   OUT LPWSTR path);
 
 PathIsUNCFunction g_path_is_unc_func;
 PathAppendFunction g_path_append_func;
 PathIsPrefixFunction g_path_is_prefix_func;
 PathFindFileName g_path_find_filename_func;
 SHGetFolderPathFunction g_get_folder_func;
 
+// Record the number of calls we've redirected so far.
+int g_redirect_count = 0;
+
 // Populates the g_*_func pointers to functions which will be used in
 // ShouldBypass(). Chrome_elf cannot have a load-time dependency on shell32 or
 // shlwapi as this would induce a load-time dependency on user32.dll. Instead,
 // the addresses of the functions we need are retrieved the first time this
 // method is called, and cached to avoid subsequent calls to GetProcAddress().
 // It is assumed that the host process will never unload these functions.
 // Returns true if all the functions needed are present.
 bool PopulateShellFunctions() {
   // Early exit if functions have already been populated.
   if (g_path_is_unc_func && g_path_append_func &&
@@ skipping 29 matching lines @@
 
 HANDLE WINAPI CreateFileWRedirect(
     LPCWSTR file_name,
     DWORD desired_access,
     DWORD share_mode,
     LPSECURITY_ATTRIBUTES security_attributes,
     DWORD creation_disposition,
     DWORD flags_and_attributes,
     HANDLE template_file) {
   if (ShouldBypass(file_name)) {
+    ++g_redirect_count;
     return CreateFileNTDLL(file_name,
                            desired_access,
                            share_mode,
                            security_attributes,
                            creation_disposition,
                            flags_and_attributes,
                            template_file);
   }
   return CreateFile(file_name,
                     desired_access,
                     share_mode,
                     security_attributes,
                     creation_disposition,
                     flags_and_attributes,
                     template_file);
 
 }
 
+int GetRedirectCount() {
+  return g_redirect_count;
+}
+
 HANDLE CreateFileNTDLL(
     LPCWSTR file_name,
     DWORD desired_access,
     DWORD share_mode,
     LPSECURITY_ATTRIBUTES security_attributes,
     DWORD creation_disposition,
     DWORD flags_and_attributes,
     HANDLE template_file) {
   HANDLE file_handle = INVALID_HANDLE_VALUE;
   NTSTATUS result = STATUS_UNSUCCESSFUL;
@@ skipping 159 matching lines @@
   LPCWSTR file_name = g_path_find_filename_func(file_path);
 
   bool in_userdata_dir = !!g_path_is_prefix_func(local_appdata_path, file_path);
   bool is_settings_file = wcscmp(file_name, kPreferencesFilename) == 0 ||
       wcscmp(file_name, kLocalStateFilename) == 0;
 
   // Check if we are trying to access the Preferences in the UserData dir. If
   // so, then redirect the call to bypass kernel32.
   return in_userdata_dir && is_settings_file;
 }