win: Remove a few instances of the "goto error" pattern.

This makes the code simpler, and also fixes a bunch of warnings that look like:

    goto done;
    ^
..\..\remoting\host\win\rdp_client_window.cc(331,14) :
      note(clang): jump bypasses variable initialization
  const LONG kDesiredFlags = WTS_PERF_ENABLE_ENHANCED_GRAPHICS |
             ^
No intended behavior change.

BUG=505296

Review URL: https://codereview.chromium.org/1226243004

Cr-Commit-Position: refs/heads/master@{#338720}

printing/printing_context_win_unittest.cc

@@ -6,6 +6,8 @@
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
+#include "base/win/scoped_handle.h"
+#include "base/win/scoped_hdc.h"
 #include "printing/backend/printing_info_win.h"
 #include "printing/backend/win_helper.h"
 #include "printing/print_settings.h"
@@ -34,6 +36,18 @@ class PrintingContextTest : public PrintingTest<testing::Test>,
   PrintingContext::Result result_;
 };
 
+namespace {
+struct FreeHandleTraits {
+  typedef HANDLE Handle;
+  static void CloseHandle(HANDLE handle) { GlobalFree(handle); }
+  static bool IsHandleValid(HANDLE handle) { return handle != NULL; }
+  static HANDLE NullHandle() { return NULL; }
+};
+typedef base::win::GenericScopedHandle<FreeHandleTraits,
+                                       base::win::DummyVerifierTraits>
+    ScopedGlobalAlloc;
+}
+
 class MockPrintingContextWin : public PrintingContextSytemDialogWin {
  public:
   MockPrintingContextWin(Delegate* delegate)
@@ -58,41 +72,31 @@ class MockPrintingContextWin : public PrintingContextSytemDialogWin {
     if (!printer.OpenPrinter(printer_name.c_str()))
       return E_FAIL;
 
-    scoped_ptr<uint8[]> buffer;
     const DEVMODE* dev_mode = NULL;
-    HRESULT result = S_OK;
     lppd->hDC = NULL;
     lppd->hDevMode = NULL;
     lppd->hDevNames = NULL;
 
     PrinterInfo2 info_2;
-    if (info_2.Init(printer.Get())) {
+    if (info_2.Init(printer.Get()))
       dev_mode = info_2.get()->pDevMode;
-    }
-    if (!dev_mode) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
+    if (!dev_mode)
+      return E_FAIL;
 
-    lppd->hDC = CreateDC(L"WINSPOOL", printer_name.c_str(), NULL, dev_mode);
-    if (!lppd->hDC) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
+    base::win::ScopedCreateDC hdc(
+        CreateDC(L"WINSPOOL", printer_name.c_str(), NULL, dev_mode));
+    if (!hdc.Get())
+      return E_FAIL;
 
     size_t dev_mode_size = dev_mode->dmSize + dev_mode->dmDriverExtra;
-    lppd->hDevMode = GlobalAlloc(GMEM_MOVEABLE, dev_mode_size);
-    if (!lppd->hDevMode) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
-    void* dev_mode_ptr = GlobalLock(lppd->hDevMode);
-    if (!dev_mode_ptr) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
+    ScopedGlobalAlloc dev_mode_mem(GlobalAlloc(GMEM_MOVEABLE, dev_mode_size));
+    if (!dev_mode_mem.Get())
+      return E_FAIL;
+    void* dev_mode_ptr = GlobalLock(dev_mode_mem.Get());
+    if (!dev_mode_ptr)
+      return E_FAIL;
     memcpy(dev_mode_ptr, dev_mode, dev_mode_size);
-    GlobalUnlock(lppd->hDevMode);
+    GlobalUnlock(dev_mode_mem.Get());
     dev_mode_ptr = NULL;
 
     size_t driver_size =
@@ -102,16 +106,12 @@ class MockPrintingContextWin : public PrintingContextSytemDialogWin {
     size_t port_size = 2 + sizeof(wchar_t) * lstrlen(info_2.get()->pPortName);
     size_t dev_names_size =
         sizeof(DEVNAMES) + driver_size + printer_size + port_size;
-    lppd->hDevNames = GlobalAlloc(GHND, dev_names_size);
-    if (!lppd->hDevNames) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
-    void* dev_names_ptr = GlobalLock(lppd->hDevNames);
-    if (!dev_names_ptr) {
-      result = E_FAIL;
-      goto Cleanup;
-    }
+    ScopedGlobalAlloc dev_names_mem(GlobalAlloc(GHND, dev_names_size));
+    if (!dev_names_mem.Get())
+      return E_FAIL;
+    void* dev_names_ptr = GlobalLock(dev_names_mem.Get());
+    if (!dev_names_ptr)
+      return E_FAIL;
     DEVNAMES* dev_names = reinterpret_cast<DEVNAMES*>(dev_names_ptr);
     dev_names->wDefault = 1;
     dev_names->wDriverOffset = sizeof(DEVNAMES) / sizeof(wchar_t);
@@ -128,27 +128,13 @@ class MockPrintingContextWin : public PrintingContextSytemDialogWin {
     memcpy(reinterpret_cast<uint8*>(dev_names_ptr) + dev_names->wOutputOffset,
            info_2.get()->pPortName,
            port_size);
-    GlobalUnlock(lppd->hDevNames);
+    GlobalUnlock(dev_names_mem.Get());
     dev_names_ptr = NULL;
 
-  Cleanup:
-    // Note: This section does proper deallocation/free of DC/global handles. We
-    //       did not use ScopedHGlobal or ScopedHandle because they did not
-    //       perform what we need.  Goto's are used based on Windows programming
-    //       idiom, to avoid deeply nested if's, and try-catch-finally is not
-    //       allowed in Chromium.
-    if (FAILED(result)) {
-      if (lppd->hDC) {
-        DeleteDC(lppd->hDC);
-      }
-      if (lppd->hDevMode) {
-        GlobalFree(lppd->hDevMode);
-      }
-      if (lppd->hDevNames) {
-        GlobalFree(lppd->hDevNames);
-      }
-    }
-    return result;
+    lppd->hDC = hdc.Take();
+    lppd->hDevMode = dev_mode_mem.Take();
+    lppd->hDevNames = dev_names_mem.Take();
+    return S_OK;
   }
 };
 

remoting/host/win/rdp_client_window.cc

@@ -247,10 +247,8 @@ LRESULT RdpClientWindow::OnCreate(CREATESTRUCT* create_struct) {
   RECT rect = { 0, 0, screen_size_.width(), screen_size_.height() };
   activex_window.Create(m_hWnd, rect, nullptr,
                         WS_CHILD | WS_VISIBLE | WS_BORDER);
-  if (activex_window.m_hWnd == nullptr) {
-    result = HRESULT_FROM_WIN32(GetLastError());
-    goto done;
-  }
+  if (activex_window.m_hWnd == nullptr)
+    return LogOnCreateError(HRESULT_FROM_WIN32(GetLastError()));
 
   // Instantiate the RDP ActiveX control.
   result = activex_window.CreateControlEx(
@@ -261,71 +259,71 @@ LRESULT RdpClientWindow::OnCreate(CREATESTRUCT* create_struct) {
       __uuidof(mstsc::IMsTscAxEvents),
       reinterpret_cast<IUnknown*>(static_cast<RdpEventsSink*>(this)));
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   result = control.QueryInterface(client_.Receive());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Use 32-bit color.
   result = client_->put_ColorDepth(32);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Set dimensions of the remote desktop.
   result = client_->put_DesktopWidth(screen_size_.width());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
   result = client_->put_DesktopHeight(screen_size_.height());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Set the server name to connect to.
   result = client_->put_Server(server_name);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Fetch IMsRdpClientAdvancedSettings interface for the client.
   result = client_->get_AdvancedSettings2(client_settings_.Receive());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Disable background input mode.
   result = client_settings_->put_allowBackgroundInput(0);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Do not use bitmap cache.
   result = client_settings_->put_BitmapPersistence(0);
   if (SUCCEEDED(result))
     result = client_settings_->put_CachePersistenceActive(0);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Do not use compression.
   result = client_settings_->put_Compress(0);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Enable the Ctrl+Alt+Del screen.
   result = client_settings_->put_DisableCtrlAltDel(0);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Disable printer and clipboard redirection.
   result = client_settings_->put_DisableRdpdr(FALSE);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Do not display the connection bar.
   result = client_settings_->put_DisplayConnectionBar(VARIANT_FALSE);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Do not grab focus on connect.
   result = client_settings_->put_GrabFocusOnConnect(VARIANT_FALSE);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Enable enhanced graphics, font smoothing and desktop composition.
   const LONG kDesiredFlags = WTS_PERF_ENABLE_ENHANCED_GRAPHICS |
@@ -333,12 +331,12 @@ LRESULT RdpClientWindow::OnCreate(CREATESTRUCT* create_struct) {
                              WTS_PERF_ENABLE_DESKTOP_COMPOSITION;
   result = client_settings_->put_PerformanceFlags(kDesiredFlags);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Set the port to connect to.
   result = client_settings_->put_RDPPort(server_endpoint_.port());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Disable audio in the session.
   // TODO(alexeypa): re-enable audio redirection when http://crbug.com/242312 is
@@ -347,12 +345,12 @@ LRESULT RdpClientWindow::OnCreate(CREATESTRUCT* create_struct) {
   if (SUCCEEDED(result)) {
     result = secured_settings2->put_AudioRedirectionMode(kRdpAudioModeNone);
     if (FAILED(result))
-      goto done;
+      return LogOnCreateError(result);
   }
 
   result = client_->get_SecuredSettings(secured_settings.Receive());
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   // Set the terminal ID as the working directory for the initial program. It is
   // observed that |WorkDir| is used only if an initial program is also
@@ -363,21 +361,11 @@ LRESULT RdpClientWindow::OnCreate(CREATESTRUCT* create_struct) {
   // This code should be in sync with WtsTerminalMonitor::LookupTerminalId().
   result = secured_settings->put_WorkDir(terminal_id);
   if (FAILED(result))
-    goto done;
+    return LogOnCreateError(result);
 
   result = client_->Connect();
   if (FAILED(result))
-    goto done;
-
-done:
-  if (FAILED(result)) {
-    LOG(ERROR) << "RDP: failed to initiate a connection to "
-               << server_endpoint_.ToString() << ": error="
-               << std::hex << result << std::dec;
-    client_.Release();
-    client_settings_.Release();
-    return -1;
-  }
+    return LogOnCreateError(result);
 
   return 0;
 }
@@ -462,6 +450,15 @@ HRESULT RdpClientWindow::OnConfirmClose(VARIANT_BOOL* allow_close) {
   return S_OK;
 }
 
+int RdpClientWindow::LogOnCreateError(HRESULT error) {
+  LOG(ERROR) << "RDP: failed to initiate a connection to "
+             << server_endpoint_.ToString() << ": error="
+             << std::hex << error << std::dec;
+  client_.Release();
+  client_settings_.Release();
+  return -1;
+}
+
 void RdpClientWindow::NotifyConnected() {
   if (event_handler_)
     event_handler_->OnConnected();

remoting/host/win/rdp_client_window.h

@@ -126,6 +126,8 @@ class RdpClientWindow
   STDMETHOD(OnFatalError)(long error_code);
   STDMETHOD(OnConfirmClose)(VARIANT_BOOL* allow_close);
 
+  int LogOnCreateError(HRESULT error);
+
   // Wrappers for the event handler's methods that make sure that
   // OnDisconnected() is the last notification delivered and is delevered
   // only once.