Create a "GetWOW64Status()" utility function and make the rest of the codebase call it.

BUG=none
TEST=none
Review URL: http://codereview.chromium.org/6610029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@76854 0039d316-1c4b-4281-b951-d872f2087c98

12 files changed, 89 insertions, 144 deletions

diff --git a/base/win/windows_version.cc b/base/win/windows_version.cc
index a80688c..9abf1d2 100644
--- a/base/win/windows_version.cc
+++ b/base/win/windows_version.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -68,5 +68,23 @@ void GetServicePackLevel(int* major, int* minor) {
   *minor = service_pack_minor;
 }
 
+WOW64Status GetWOW64Status() {
+  static WOW64Status wow64_status =
+      GetWOW64StatusForProcess(GetCurrentProcess());
+  return wow64_status;
+}
+
+WOW64Status GetWOW64StatusForProcess(HANDLE process_handle) {
+  typedef BOOL (WINAPI* IsWow64ProcessFunc)(HANDLE, PBOOL);
+  IsWow64ProcessFunc is_wow64_process = reinterpret_cast<IsWow64ProcessFunc>(
+      GetProcAddress(GetModuleHandle(L"kernel32.dll"), "IsWow64Process"));
+  if (!is_wow64_process)
+    return WOW64_DISABLED;
+  BOOL is_wow64 = FALSE;
+  if (!(*is_wow64_process)(process_handle, &is_wow64))
+    return WOW64_UNKNOWN;
+  return is_wow64 ? WOW64_ENABLED : WOW64_DISABLED;
+}
+
 }  // namespace win
 }  // namespace base
diff --git a/base/win/windows_version.h b/base/win/windows_version.h
index 7e281a6..0cfb2c7 100644
--- a/base/win/windows_version.h
+++ b/base/win/windows_version.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -6,6 +6,8 @@
 #define BASE_WIN_WINDOWS_VERSION_H_
 #pragma once
 
+typedef void* HANDLE;
+
 namespace base {
 namespace win {
 
@@ -28,6 +30,23 @@ Version GetVersion();
 // Returns the major and minor version of the service pack installed.
 void GetServicePackLevel(int* major, int* minor);
 
+enum WOW64Status {
+  WOW64_DISABLED,
+  WOW64_ENABLED,
+  WOW64_UNKNOWN,
+};
+
+// Returns whether this process is running under WOW64 (the wrapper that allows
+// 32-bit processes to run on 64-bit versions of Windows).  This will return
+// WOW64_DISABLED for both "32-bit Chrome on 32-bit Windows" and "64-bit Chrome
+// on 64-bit Windows".  WOW64_UNKNOWN means "an error occurred", e.g. the
+// process does not have sufficient access rights to determine this.
+WOW64Status GetWOW64Status();
+
+// Like GetWOW64Status(), but for the supplied handle instead of the current
+// process.
+WOW64Status GetWOW64StatusForProcess(HANDLE process_handle);
+
 }  // namespace win
 }  // namespace base
 
diff --git a/chrome/browser/memory_details_win.cc b/chrome/browser/memory_details_win.cc
index 0e9f063..edb53c8 100644
--- a/chrome/browser/memory_details_win.cc
+++ b/chrome/browser/memory_details_win.cc
@@ -11,6 +11,7 @@
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/scoped_handle.h"
+#include "base/win/windows_version.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/url_constants.h"
 #include "content/browser/browser_child_process_host.h"
@@ -89,19 +90,13 @@ void MemoryDetails::CollectProcessData(
   }
   do {
     base::ProcessId pid = process_entry.th32ProcessID;
-    base::win::ScopedHandle handle(::OpenProcess(
+    base::win::ScopedHandle process_handle(::OpenProcess(
         PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, FALSE, pid));
-    if (!handle.Get())
+    if (!process_handle.Get())
       continue;
-    bool is_64bit_process = false;
-    // IsWow64Process() returns FALSE for a 32bit process on a 32bit OS.
-    // We need to check if the real OS is 64bit.
-    if (is_64bit_os) {
-      BOOL is_wow64 = FALSE;
-      // IsWow64Process() is supported by Windows XP SP2 or later.
-      IsWow64Process(handle, &is_wow64);
-      is_64bit_process = !is_wow64;
-    }
+    bool is_64bit_process = is_64bit_os &&
+        (base::win::GetWOW64StatusForProcess(process_handle) ==
+            base::win::WOW64_DISABLED);
     for (unsigned int index2 = 0; index2 < process_data_.size(); index2++) {
       if (_wcsicmp(process_data_[index2].process_name.c_str(),
                    process_entry.szExeFile) != 0)
@@ -117,7 +112,7 @@ void MemoryDetails::CollectProcessData(
         info.type = ChildProcessInfo::UNKNOWN_PROCESS;
 
       scoped_ptr<base::ProcessMetrics> metrics;
-      metrics.reset(base::ProcessMetrics::CreateProcessMetrics(handle));
+      metrics.reset(base::ProcessMetrics::CreateProcessMetrics(process_handle));
       metrics->GetCommittedKBytes(&info.committed);
       metrics->GetWorkingSetKBytes(&info.working_set);
 
@@ -136,7 +131,8 @@ void MemoryDetails::CollectProcessData(
           info.type = child_info[child].type;
           break;
         }
-      } else if (GetModuleFileNameEx(handle, NULL, name, MAX_PATH - 1)) {
+      } else if (GetModuleFileNameEx(process_handle, NULL, name,
+                                     MAX_PATH - 1)) {
         std::wstring str_name(name);
         scoped_ptr<FileVersionInfo> version_info(
             FileVersionInfo::CreateFileVersionInfo(FilePath(str_name)));
diff --git a/chrome/browser/nacl_host/nacl_process_host.cc b/chrome/browser/nacl_host/nacl_process_host.cc
index 2064407..2b97881 100644
--- a/chrome/browser/nacl_host/nacl_process_host.cc
+++ b/chrome/browser/nacl_host/nacl_process_host.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -13,6 +13,7 @@
 #include "base/command_line.h"
 #include "base/metrics/nacl_histogram.h"
 #include "base/utf_string_conversions.h"
+#include "base/win/windows_version.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/logging_chrome.h"
 #include "chrome/common/nacl_cmd_line.h"
@@ -58,7 +59,7 @@ NaClProcessHost::NaClProcessHost(
       running_on_wow64_(false) {
   set_name(url);
 #if defined(OS_WIN)
-  CheckIsWow64();
+  running_on_wow64_ = (base::win::GetWOW64Status() == base::win::WOW64_ENABLED);
 #endif
 }
 
@@ -301,24 +302,3 @@ bool NaClProcessHost::OnMessageReceived(const IPC::Message& msg) {
 bool NaClProcessHost::CanShutdown() {
   return true;
 }
-
-#if defined(OS_WIN)
-// TODO(gregoryd): invoke CheckIsWow64 only once, not for each NaClProcessHost
-typedef BOOL (WINAPI *LPFN_ISWOW64PROCESS) (HANDLE, PBOOL);
-void NaClProcessHost::CheckIsWow64() {
-  LPFN_ISWOW64PROCESS fnIsWow64Process;
-
-  fnIsWow64Process = (LPFN_ISWOW64PROCESS) GetProcAddress(
-      GetModuleHandle(TEXT("kernel32")),
-      "IsWow64Process");
-
-  if (fnIsWow64Process != NULL) {
-    BOOL bIsWow64 = FALSE;
-    if (fnIsWow64Process(GetCurrentProcess(),&bIsWow64)) {
-      if (bIsWow64) {
-        running_on_wow64_ = true;
-      }
-    }
-  }
-}
-#endif
diff --git a/chrome/browser/nacl_host/nacl_process_host.h b/chrome/browser/nacl_host/nacl_process_host.h
index 46c5468..b4deaea 100644
--- a/chrome/browser/nacl_host/nacl_process_host.h
+++ b/chrome/browser/nacl_host/nacl_process_host.h
@@ -54,11 +54,6 @@ class NaClProcessHost : public BrowserChildProcessHost {
 
   virtual bool CanShutdown();
 
-#if defined(OS_WIN)
-  // Check whether the browser process is running on WOW64 - Windows only
-  void CheckIsWow64();
-#endif
-
  private:
   ResourceDispatcherHost* resource_dispatcher_host_;
 
diff --git a/chrome/installer/setup/install_worker.cc b/chrome/installer/setup/install_worker.cc
index 495d3b1..70e1ab6 100644
--- a/chrome/installer/setup/install_worker.cc
+++ b/chrome/installer/setup/install_worker.cc
@@ -19,6 +19,7 @@
 #include "base/utf_string_conversions.h"
 #include "base/version.h"
 #include "base/win/registry.h"
+#include "base/win/windows_version.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/installer/setup/install.h"
 #include "chrome/installer/setup/setup_constants.h"
@@ -39,24 +40,6 @@
 
 using base::win::RegKey;
 
-namespace {
-
-// This method tells if we are running on 64 bit platform so that we can copy
-// one extra exe. If the API call to determine 64 bit fails, we play it safe
-// and return true anyway so that the executable can be copied.
-bool Is64bit() {
-  typedef BOOL (WINAPI* WOW_FUNC)(HANDLE, BOOL*);
-  BOOL is_64 = FALSE;
-
-  HMODULE module = GetModuleHandle(L"kernel32.dll");
-  WOW_FUNC is_wow64 = reinterpret_cast<WOW_FUNC>(
-      GetProcAddress(module, "IsWow64Process"));
-  return (is_wow64 != NULL) &&
-           (!(is_wow64)(GetCurrentProcess(), &is_64) || (is_64 != FALSE));
-}
-
-}  // namespace
-
 namespace installer {
 
 // Local helper to call AddRegisterComDllWorkItems for all DLLs in a set of
@@ -556,7 +539,9 @@ void AddInstallWorkItems(const InstallationState& original_state,
       temp_path.value(), WorkItem::NEW_NAME_IF_IN_USE, new_chrome_exe.value());
 
   // Extra executable for 64 bit systems.
-  if (Is64bit()) {
+  // NOTE: We check for "not disabled" so that if the API call fails, we play it
+  // safe and copy the executable anyway.
+  if (base::win::GetWOW64Status() != base::win::WOW64_DISABLED) {
     install_list->AddMoveTreeWorkItem(
         src_path.Append(installer::kWowHelperExe).value(),
         target_path.Append(installer::kWowHelperExe).value(),
diff --git a/sandbox/src/Wow64.cc b/sandbox/src/Wow64.cc
index dec5e50..79febe8 100644
--- a/sandbox/src/Wow64.cc
+++ b/sandbox/src/Wow64.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -8,7 +8,7 @@
 
 #include "base/logging.h"
 #include "base/scoped_ptr.h"
-#include "sandbox/src/sandbox.h"
+#include "base/win/windows_version.h"
 #include "sandbox/src/target_process.h"
 
 namespace {
@@ -80,33 +80,6 @@ Wow64::~Wow64() {
     ::CloseHandle(continue_load_);
 }
 
-bool Wow64::IsWow64() {
-  if (init_)
-    return is_wow64_;
-
-  is_wow64_ = false;
-
-  HMODULE kernel32 = ::GetModuleHandle(sandbox::kKerneldllName);
-  if (!kernel32)
-    return false;
-
-  IsWow64ProcessFunction is_wow64_process = reinterpret_cast<
-      IsWow64ProcessFunction>(::GetProcAddress(kernel32, "IsWow64Process"));
-
-  init_ = true;
-  if (!is_wow64_process)
-    return false;
-
-  BOOL wow64;
-  if (!is_wow64_process(::GetCurrentProcess(), &wow64))
-    return false;
-
-  if (wow64)
-    is_wow64_ = true;
-
-  return is_wow64_;
-}
-
 // The basic idea is to allocate one page of memory on the child, and initialize
 // the first part of it with our version of PatchInfo32. Then launch the helper
 // process passing it that address on the child. The helper process will patch
@@ -114,9 +87,8 @@ bool Wow64::IsWow64() {
 // first event on the buffer. We'll be waiting on that event and after the 32
 // bit version of ntdll is loaded, we'll remove the interception and return to
 // our caller.
-bool Wow64::WaitForNtdll(DWORD timeout_ms) {
-  DCHECK(!init_);
-  if (!IsWow64())
+bool Wow64::WaitForNtdll() {
+  if (base::win::GetWOW64Status() != base::win::WOW64_ENABLED)
     return true;
 
   const size_t page_size = 4096;
@@ -151,19 +123,19 @@ bool Wow64::WaitForNtdll(DWORD timeout_ms) {
   if (offsetof(PatchInfo32, section) != written)
     return false;
 
-  if (!RunWowHelper(buffer, timeout_ms))
+  if (!RunWowHelper(buffer))
     return false;
 
   // The child is intercepted on 64 bit, go on and wait for our event.
-  if (!DllMapped(timeout_ms))
+  if (!DllMapped())
     return false;
 
   // The 32 bit version is available, cleanup the child.
   return Restore64Code(child_->Process(), patch_info);
 }
 
-bool Wow64::RunWowHelper(void* buffer, DWORD timeout_ms) {
-  COMPILE_ASSERT(sizeof(buffer) <= sizeof(timeout_ms), unsupported_64_bits);
+bool Wow64::RunWowHelper(void* buffer) {
+  COMPILE_ASSERT(sizeof(buffer) <= sizeof DWORD, unsupported_64_bits);
 
   // Get the path to the helper (beside the exe).
   wchar_t prog_name[MAX_PATH];
@@ -188,7 +160,7 @@ bool Wow64::RunWowHelper(void* buffer, DWORD timeout_ms) {
                        NULL, &startup_info, &process_info))
     return false;
 
-  DWORD reason = ::WaitForSingleObject(process_info.hProcess, timeout_ms);
+  DWORD reason = ::WaitForSingleObject(process_info.hProcess, INFINITE);
 
   DWORD code;
   bool ok = ::GetExitCodeProcess(process_info.hProcess, &code) ? true : false;
@@ -204,14 +176,14 @@ bool Wow64::RunWowHelper(void* buffer, DWORD timeout_ms) {
 
 // First we must wake up the child, then wait for dll loads on the child until
 // the one we care is loaded; at that point we must suspend the child again.
-bool Wow64::DllMapped(DWORD timeout_ms) {
+bool Wow64::DllMapped() {
   if (1 != ::ResumeThread(child_->MainThread())) {
     NOTREACHED();
     return false;
   }
 
   for (;;) {
-    DWORD reason = ::WaitForSingleObject(dll_load_, timeout_ms);
+    DWORD reason = ::WaitForSingleObject(dll_load_, INFINITE);
     if (WAIT_TIMEOUT == reason || WAIT_ABANDONED == reason)
       return false;
 
diff --git a/sandbox/src/Wow64.h b/sandbox/src/Wow64.h
index 7ee981a..472297e 100644
--- a/sandbox/src/Wow64.h
+++ b/sandbox/src/Wow64.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -19,25 +19,21 @@ class TargetProcess;
 class Wow64 {
  public:
   Wow64(TargetProcess* child, HMODULE ntdll)
-      : child_(child), ntdll_(ntdll), init_(false), dll_load_(NULL),
-        continue_load_(NULL) {}
+      : child_(child), ntdll_(ntdll), dll_load_(NULL), continue_load_(NULL) {}
   ~Wow64();
 
   // Waits for the 32 bit DLL to get loaded on the child process. This function
   // will return immediately if not running under WOW, or launch the helper
   // process and wait until ntdll is ready.
-  bool WaitForNtdll(DWORD timeout_ms);
-
-  // Returns true if this is a 32 bit process running on a 64 bit OS.
-  bool IsWow64();
+  bool WaitForNtdll();
 
  private:
   // Runs the WOW helper process, passing the address of a buffer allocated on
   // the child (one page).
-  bool RunWowHelper(void* buffer, DWORD timeout_ms);
+  bool RunWowHelper(void* buffer);
 
   // This method receives "notifications" whenever a DLL is mapped on the child.
-  bool DllMapped(DWORD timeout_ms);
+  bool DllMapped();
 
   // Returns true if ntdll.dll is mapped on the child.
   bool NtdllPresent();
@@ -46,8 +42,6 @@ class Wow64 {
   HMODULE ntdll_;         // ntdll on the parent.
   HANDLE dll_load_;       // Event that is signaled on dll load.
   HANDLE continue_load_;  // Event to signal to continue execution on the child.
-  bool init_;             // Initialization control.
-  bool is_wow64_;         // true on WOW64 environments.
   DISALLOW_IMPLICIT_CONSTRUCTORS(Wow64);
 };
 
diff --git a/sandbox/src/Wow64_64.cc b/sandbox/src/Wow64_64.cc
index e188d68..5218077 100644
--- a/sandbox/src/Wow64_64.cc
+++ b/sandbox/src/Wow64_64.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -11,11 +11,7 @@ namespace sandbox {
 Wow64::~Wow64() {
 }
 
-bool Wow64::IsWow64() {
-  return false;
-}
-
-bool Wow64::WaitForNtdll(DWORD timeout_ms) {
+bool Wow64::WaitForNtdll() {
   return true;
 }
 
diff --git a/sandbox/src/interception.cc b/sandbox/src/interception.cc
index 6636cc3..e9f89dc 100644
--- a/sandbox/src/interception.cc
+++ b/sandbox/src/interception.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -424,9 +424,9 @@ bool InterceptionManager::PatchClientFunctions(DllInterceptionData* thunks,
       return false;
   }
 
-  Wow64 WowHelper(child_, ntdll_base);
   if (base::win::GetVersion() <= base::win::VERSION_VISTA) {
-    if (!WowHelper.WaitForNtdll(INFINITE))
+    Wow64 WowHelper(child_, ntdll_base);
+    if (!WowHelper.WaitForNtdll())
       return false;
   }
 
@@ -438,7 +438,7 @@ bool InterceptionManager::PatchClientFunctions(DllInterceptionData* thunks,
 #endif
 
   ServiceResolverThunk* thunk;
-  if (WowHelper.IsWow64())
+  if (base::win::GetWOW64Status() == base::win::WOW64_ENABLED)
     thunk = new Wow64ResolverThunk(child_->Process(), relaxed_);
   else if (!IsXPSP2OrLater())
     thunk = new Win2kResolverThunk(child_->Process(), relaxed_);
diff --git a/sandbox/src/service_resolver_unittest.cc b/sandbox/src/service_resolver_unittest.cc
index 793d4a1..777a5da 100644
--- a/sandbox/src/service_resolver_unittest.cc
+++ b/sandbox/src/service_resolver_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -6,10 +6,10 @@
 
 #include "base/basictypes.h"
 #include "base/scoped_ptr.h"
+#include "base/win/windows_version.h"
 #include "sandbox/src/resolver.h"
 #include "sandbox/src/sandbox_utils.h"
 #include "sandbox/src/service_resolver.h"
-#include "sandbox/src/wow64.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
@@ -120,18 +120,11 @@ NTSTATUS PatchNtdllWithResolver(const char* function, bool relaxed,
 }
 
 sandbox::ServiceResolverThunk* GetTestResolver(bool relaxed) {
-  HMODULE ntdll_base = ::GetModuleHandle(L"ntdll.dll");
-  EXPECT_TRUE(NULL != ntdll_base);
-  sandbox::Wow64 WowHelper(NULL, ntdll_base);
-
-  sandbox::ServiceResolverThunk* resolver;
-  if (WowHelper.IsWow64())
-    resolver = new Wow64ResolverTest(relaxed);
-  else if (!sandbox::IsXPSP2OrLater())
-    resolver = new Win2kResolverTest(relaxed);
-  else
-    resolver = new WinXpResolverTest(relaxed);
-  return resolver;
+  if (base::win::GetWOW64Status() == base::win::WOW64_ENABLED)
+    return new Wow64ResolverTest(relaxed);
+  if (!sandbox::IsXPSP2OrLater())
+    return new Win2kResolverTest(relaxed);
+  return new WinXpResolverTest(relaxed);
 }
 
 NTSTATUS PatchNtdll(const char* function, bool relaxed) {
diff --git a/sandbox/tests/common/controller.cc b/sandbox/tests/common/controller.cc
index 6e0f080..7efd374 100644
--- a/sandbox/tests/common/controller.cc
+++ b/sandbox/tests/common/controller.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -6,9 +6,9 @@
 
 #include <string>
 
+#include "base/win/windows_version.h"
 #include "sandbox/src/sandbox_factory.h"
 #include "sandbox/src/sandbox_utils.h"
-#include "sandbox/src/wow64.h"
 
 namespace {
 
@@ -55,11 +55,9 @@ std::wstring MakePathToSysWow64(const wchar_t* name, bool is_obj_man_path) {
 namespace sandbox {
 
 std::wstring MakePathToSys(const wchar_t* name, bool is_obj_man_path) {
-  Wow64 current_proc(NULL, NULL);
-  if (current_proc.IsWow64())
+  if (base::win::GetWOW64Status() == base::win::WOW64_ENABLED)
     return MakePathToSysWow64(name, is_obj_man_path);
-  else
-    return MakePathToSys32(name, is_obj_man_path);
+  return MakePathToSys32(name, is_obj_man_path);
 }
 
 BrokerServices* GetBroker() {
@@ -140,8 +138,7 @@ bool TestRunner::AddRuleSys32(TargetPolicy::Semantics semantics,
   if (!AddRule(TargetPolicy::SUBSYS_FILES, semantics, win32_path.c_str()))
     return false;
 
-  Wow64 current_proc(NULL, NULL);
-  if (!current_proc.IsWow64())
+  if (base::win::GetWOW64Status() != base::win::WOW64_ENABLED)
     return true;
 
   win32_path = MakePathToSysWow64(pattern, false);