Upon execution of the App Host, ask Omaha to install the Chrome Binaries if they are not present on…

chrome/browser/extensions/app_host/binaries_installer_internal.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 "chrome/browser/extensions/app_host/binaries_installer_internal.h"
+
+#include "base/logging.h"
+#include "base/win/scoped_bstr.h"
+#include "base/win/scoped_comptr.h"
+#include "google_update/google_update_idl.h"
+
+using base::win::ScopedBstr;
+using base::win::ScopedComPtr;
+
+namespace app_host {
+namespace internal {
+
+namespace {
+const wchar_t kBinariesAppId[] = L"{4DC8B4CA-1BDA-483e-B5FA-D3C12E15B62D}";
+const wchar_t kAppHostAppId[] = L"{FDA71E6F-AC4C-4a00-8B70-9958A68906BF}";
+}  // namespace
+
+bool CheckIfDone(IAppBundle* app_bundle, IApp* app, HRESULT* hr) {
+  *hr = S_OK;
+  ScopedComPtr<ICurrentState> current_state;
+  {
+    ScopedComPtr<IDispatch> idispatch;
+    *hr = app->get_currentState(idispatch.Receive());
+    if (FAILED(*hr)) {
+      LOG(ERROR) << "Failed to get App Bundle state: " << *hr;
+      return true;
+    }
+    *hr = current_state.QueryFrom(idispatch);
+    if (FAILED(*hr)) {
+      LOG(ERROR) << "get_currentState return object is not an ICurrentState.";
+      return true;
+    }
+  }
+
+  LONG long_state_value;
+  CurrentState state_value;
+  *hr = current_state->get_stateValue(&long_state_value);
+  if (FAILED(*hr)) {
+    LOG(ERROR) << "Failed to get App Bundle state value: " << *hr;
+    return true;
+  }
+  state_value = static_cast<CurrentState>(long_state_value);
+  switch (state_value) {
+    case STATE_WAITING_TO_CHECK_FOR_UPDATE:
+    case STATE_CHECKING_FOR_UPDATE:
+    case STATE_WAITING_TO_DOWNLOAD:
+    case STATE_RETRYING_DOWNLOAD:
+    case STATE_DOWNLOADING:
+    case STATE_WAITING_TO_INSTALL:
+    case STATE_INSTALLING:
+    case STATE_DOWNLOAD_COMPLETE:
+    case STATE_EXTRACTING:
+    case STATE_APPLYING_DIFFERENTIAL_PATCH:
+      // These states will all transition on their own.
+      break;
+
+    case STATE_UPDATE_AVAILABLE:
+      // If the app bundle is 'busy' we will just wait some more.
+      {
+        VARIANT_BOOL is_busy = VARIANT_TRUE;
+        *hr = app_bundle->isBusy(&is_busy);
+        if (FAILED(*hr)) {
+          LOG(ERROR) << "Failed to check app_bundle->isBusy: " << *hr;
+          return true;
+        }
+
+        if (!is_busy) {
+          *hr = app_bundle->download();
+          if (FAILED(*hr)) {
+            LOG(ERROR) << "Failed to initiate bundle download: " << *hr;
+            return true;
+          }
+        }
+      }
+      break;
+
+    case STATE_READY_TO_INSTALL:
+      // If the app bundle is 'busy' we will just wait some more.
+      {
+        VARIANT_BOOL is_busy = VARIANT_TRUE;
+        *hr = app_bundle->isBusy(&is_busy);
+        if (FAILED(*hr)) {
+          LOG(ERROR) << "Failed to check app_bundle->isBusy: " << *hr;
+          return true;

[robertshield, 2012/08/16 13:08:16]

as a readability thing, could we reduce the number of return statements? I'd
specifically prefer if there were no return statements in the switch block as it
imo makes it harder to figure which cases fall through below and which don't.

[erikwright (departed), 2012/08/16 21:05:15]

Done.

+        }
+
+        if (!is_busy) {
+          *hr = app_bundle->install();
+          if (FAILED(*hr)) {
+            LOG(ERROR) << "Failed to initiate bundle install: " << *hr;
+            return true;
+          }
+        }
+      }
+      break;
+
+    case STATE_NO_UPDATE:
+      LOG(INFO) << "Google Update reports that the binaries are already "
+                << "installed and up-to-date.";
+      *hr = S_OK;
+      return true;
+
+    case STATE_INSTALL_COMPLETE:
+      return S_OK;
+      *hr = S_OK;

[robertshield, 2012/08/16 13:08:16]

this should be warning about unreachable code

[erikwright (departed), 2012/08/16 21:05:15]

Done.

+      return true;
+
+    case STATE_ERROR: {
+      LONG error_code;
+      *hr = current_state->get_errorCode(&error_code);
+      if (FAILED(*hr)) {
+        LOG(ERROR) << "Failed to retrieve bundle error code: " << *hr;
+        return true;
+      }
+      *hr = error_code;
+      ScopedBstr completion_message;
+      HRESULT completion_message_hr =
+        current_state->get_completionMessage(completion_message.Receive());
+      if (FAILED(completion_message_hr)) {
+        LOG(ERROR) << "Bundle installation failed with error " << *hr
+                   << ". Error message retrieval failed with error: "
+                   << completion_message_hr;
+      } else {
+        LOG(ERROR) << "Bundle installation failed with error " << *hr << ": "
+                   << completion_message;
+      }
+      return true;
+    }
+
+    case STATE_INIT:
+    case STATE_PAUSED:
+      LOG(ERROR) << "Unexpected bundle state: " << state_value << ".";
+      *hr = E_FAIL;
+      return true;
+
+    default:
+      LOG(ERROR) << "Unknown bundle state: " << state_value << ".";
+      *hr = E_FAIL;
+      return true;
+  }
+
+  DCHECK_EQ(*hr, S_OK);
+  return false;
+}
+
+HRESULT CreateAppBundle(IGoogleUpdate3* update3, IAppBundle** app_bundle) {
+  HRESULT hr = S_OK;
+  ScopedComPtr<IAppBundle> temp_app_bundle;
+  {
+    ScopedComPtr<IDispatch> idispatch;
+    hr = update3->createAppBundle(idispatch.Receive());
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Failed to createAppBundle: " << hr;
+      return hr;
+    }
+
+    hr = temp_app_bundle.QueryFrom(idispatch);
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Unexpected error: " << hr;
+      return hr;
+    }
+  }
+
+  hr = temp_app_bundle->initialize();
+  if (FAILED(hr)) {
+    LOG(ERROR) << "Failed to initialize App Bundle: " << hr;
+    return hr;
+  }
+
+  *app_bundle = temp_app_bundle.Detach();
+
+  return S_OK;
+}
+
+HRESULT GetAppHostAPValue(IGoogleUpdate3* update3, BSTR* ap_value) {
+  ScopedComPtr<IAppBundle> app_bundle;
+  HRESULT hr = CreateAppBundle(update3, app_bundle.Receive());
+  if (FAILED(hr)) {
+    return hr;
+  }
+
+  ScopedComPtr<IApp> app;
+  {
+    ScopedComPtr<IDispatch> idispatch;
+    hr = app_bundle->createInstalledApp(ScopedBstr(kAppHostAppId),
+                                        idispatch.Receive());
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Failed to configure App Bundle: " << hr;
+      return hr;

[robertshield, 2012/08/16 13:08:16]

I would encourage you to rewrite stuff like this with fewer return statements as
well, though I don't feel as strongly for shorter functions.

[erikwright (departed), 2012/08/16 21:05:15]

Done.

+    }
+    hr = app.QueryFrom(idispatch);
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Unexpected error: " << hr;
+      return hr;
+    }
+  }
+  hr = app->get_ap(ap_value);
+  if (FAILED(hr)) {
+    LOG(ERROR) << "Failed to get the App Host AP value.";
+    return hr;
+  }
+  return S_OK;
+}
+
+HRESULT CreateBinariesIApp(IAppBundle* app_bundle, BSTR ap, IApp** app) {

[robertshield, 2012/08/16 13:08:16]

app, ap, and app_bundle :) maybe ap -> "channel_value"?

[erikwright (departed), 2012/08/16 21:05:15]

What does AP stand for?

[robertshield, 2012/08/16 21:15:53]

That knowledge is lost in the sands of time. Omaha folk might know.

+  HRESULT hr(S_OK);
+  ScopedComPtr<IApp> temp_app;
+  {
+    ScopedComPtr<IDispatch> idispatch;
+    hr = app_bundle->createApp(ScopedBstr(kBinariesAppId), idispatch.Receive());
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Failed to configure App Bundle: " << hr;
+      return hr;
+    }
+    hr = temp_app.QueryFrom(idispatch);
+    if (FAILED(hr)) {
+      LOG(ERROR) << "Unexpected error: " << hr;
+      return hr;
+    }
+  }
+  hr = temp_app->put_isEulaAccepted(VARIANT_TRUE);
+  if (FAILED(hr)) {
+    LOG(ERROR) << "Failed to set 'EULA Accepted': " << hr;
+    return hr;
+  }
+  hr = temp_app->put_ap(ap);
+  if (FAILED(hr)) {
+    LOG(ERROR) << "Failed to set AP value: " << hr;
+    return hr;
+  }
+  *app = temp_app.Detach();
+  return S_OK;
+}
+
+HRESULT CreateGoogleUpdate3(IGoogleUpdate3** update3) {
+  ScopedComPtr<IGoogleUpdate3> temp_update3;
+  HRESULT hr = temp_update3.CreateInstance(CLSID_GoogleUpdate3UserClass);
+  if (FAILED(hr)) {
+    // TODO(erikwright): Try in-proc to support running elevated? According
+    // to update3_utils.cc (CreateGoogleUpdate3UserClass):
+    // The primary reason for the LocalServer activation failing on Vista/Win7
+    // is that COM does not look at HKCU registration when the code is running
+    // elevated. We fall back to an in-proc mode. The in-proc mode is limited to
+    // one install at a time, so we use it only as a backup mechanism.
+    LOG(ERROR) << "Failed to instantiate GoogleUpdate3: " << hr;
+  } else {
+    *update3 = temp_update3.Detach();
+  }
+  return hr;
+}
+
+HRESULT SelectBinariesApValue(IGoogleUpdate3* update3, BSTR* ap_value) {
+  HRESULT hr = GetAppHostAPValue(update3, ap_value);
+  if (FAILED(hr)) {
+    // TODO(erikwright): distinguish between AppHost not installed and an
+    // error in GetAppHostAPValue.
+    // TODO(erikwright): Use stable by default when App Host support is in
+    // stable.
+    ScopedBstr temp_ap_value;
+    if (NULL == temp_ap_value.Allocate(L"2.0-dev-multi-apphost")) {
+      LOG(ERROR) << "Unexpected error in ScopedBstr::Allocate.";
+      hr = E_FAIL;
+    } else {
+      *ap_value = temp_ap_value.Release();
+      hr = S_OK;
+    }
+  }
+
+  return hr;
+}
+
+}  // namespace internal
+}  // namespace app_host