Ensure Dxgi duplicator works correctly in session 0

webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc

Index: webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc
diff --git a/webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc b/webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc
index c17bd1481c7fffa9e09939e3fbcb75f70deaee87..75c3ed11b6e83032648d7db7c0a66e28a1a0cc85 100644
--- a/webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc
+++ b/webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.cc
@@ -16,7 +16,9 @@
 #include <string>
 
 #include "webrtc/base/checks.h"
+#include "webrtc/base/logging.h"
 #include "webrtc/base/timeutils.h"
+#include "webrtc/base/win32.h"
 #include "webrtc/modules/desktop_capture/desktop_capture_types.h"
 #include "webrtc/modules/desktop_capture/win/dxgi_frame.h"
 #include "webrtc/modules/desktop_capture/win/screen_capture_utils.h"
@@ -24,6 +26,19 @@
 
 namespace webrtc {
 
+namespace {
+
+bool IsRunningInSession0() {
+  DWORD session_id = 0;
+  if (!::ProcessIdToSessionId(::GetCurrentProcessId(), &session_id)) {
+    LOG(LS_WARNING) << "Failed to retrieve current session Id, no priviledge?";
+    return true;
+  }
+  return session_id == 0;
+}
+
+}  // namespace
+
 // static
 DxgiDuplicatorController* DxgiDuplicatorController::Instance() {
   // The static instance won't be deleted to ensure it can be used by other
@@ -40,17 +55,48 @@ DxgiDuplicatorController::~DxgiDuplicatorController() {
 }
 
 bool DxgiDuplicatorController::IsSupported() {
-  rtc::CritScope lock(&lock_);
-  return Initialize();
+  bool result = false;
+  {
+    rtc::CritScope lock(&lock_);
+    result = Initialize();
+  }
+
+  if (result) {
+    return true;
+  }
+
+  if (IsRunningInSession0()) {
+    LOG(LS_WARNING) << "Current binary is running in session 0. DXGI "
+                       "components cannot be initialized. Fallback to use "
+                       "Windows version to decide the support of DirectX "
+                       "capturer. It may be inaccurate.";
+    return rtc::IsWindows8OrLater();

[Sergey Ulanov, 2017/06/26 23:41:41]

In this case DX capturer is effectively unsupported, but 
DxgiDuplicatorController::IsSupported() still returns true. This doesn't look
right to me. Does this case need to be handled here? Can we handle in the
chromoting host directly?

[Hzj_jie, 2017/06/27 04:37:33]

A very good point, I have moved this logic into
https://codereview.chromium.org/2941623003/.

+  }
+
+  return false;
 }
 
 bool DxgiDuplicatorController::RetrieveD3dInfo(D3dInfo* info) {
-  rtc::CritScope lock(&lock_);
-  if (!Initialize()) {
-    return false;
+  bool result = false;
+  {
+    rtc::CritScope lock(&lock_);
+    result = Initialize();
   }
-  *info = d3d_info_;
-  return true;
+
+  if (result) {
+    *info = d3d_info_;
+    return true;
+  }
+
+  if (IsRunningInSession0()) {
+    LOG(LS_WARNING) << "Current binary is running in session 0. Initialization "
+                       "of DXGI components are expected to fail. But "
+                       "retrieving feature level is still supported.";
+    *info = d3d_info_;
+    return true;
+  }
+
+  return false;
 }
 
 DxgiDuplicatorController::Result
@@ -104,6 +150,12 @@ DxgiDuplicatorController::DoDuplicate(DxgiFrame* frame, int monitor_id) {
   }
 
   if (!Initialize()) {
+    if (succeeded_duplications_ == 0 && IsRunningInSession0()) {
+      LOG(LS_WARNING) << "Current binary is running in session 0. DXGI "
+                         "components cannot be initialized.";
+      return Result::UNSUPPORTED_SESSION;
+    }
+
     // Cannot initialize COM components now, display mode may be changing.
     return Result::INITIALIZATION_FAILED;
   }
@@ -115,6 +167,7 @@ DxgiDuplicatorController::DoDuplicate(DxgiFrame* frame, int monitor_id) {
   frame->frame()->mutable_updated_region()->Clear();
 
   if (DoDuplicateUnlocked(frame->context(), monitor_id, frame->frame())) {
+    succeeded_duplications_++;
     return Result::SUCCEEDED;
   }
   if (monitor_id >= ScreenCountUnlocked()) {
@@ -162,15 +215,11 @@ bool DxgiDuplicatorController::DoInitialize() {
 
   std::vector<D3dDevice> devices = D3dDevice::EnumDevices();
   if (devices.empty()) {
+    LOG(LS_WARNING) << "No D3dDevice found.";
     return false;
   }
 
   for (size_t i = 0; i < devices.size(); i++) {
-    duplicators_.emplace_back(devices[i]);
-    if (!duplicators_.back().Initialize()) {
-      return false;
-    }
-
     D3D_FEATURE_LEVEL feature_level =
         devices[i].d3d_device()->GetFeatureLevel();
     if (d3d_info_.max_feature_level == 0 ||
@@ -182,6 +231,16 @@ bool DxgiDuplicatorController::DoInitialize() {
       d3d_info_.min_feature_level = feature_level;
     }
 
+    DxgiAdapterDuplicator duplicator(devices[i]);
+    if (!duplicator.Initialize()) {
+      LOG(LS_WARNING) << "Failed to initialize DxgiAdapterDuplicator on "
+                         "adapter "
+                      << i;
+      continue;

[Sergey Ulanov, 2017/06/26 23:41:41]

Why do we need to keep trying initialization after initialization of a single
adapter fails? Maybe document add a comment somewhere? I also don't understand
how it's related to this change.

[Hzj_jie, 2017/06/27 04:37:33]

This issue happens when a virtual adapter is installed on to the system, but the
virtual adapter does not support DX11 or upper. I encountered this issue when
D3D gear was installed.
But if there are two physical video cards, and both of them are connecting to
monitors. IMO, it's safe to assume they support a same DX version. It's very
hard to imagine someone is using a DX 11 video card with a DX 10 one, which has
a 3-year gap.
Comments have been added.

+    }
+    RTC_DCHECK(!duplicator.desktop_rect().is_empty());
+    duplicators_.push_back(std::move(duplicator));
+
     desktop_rect_.UnionWith(duplicators_.back().desktop_rect());
   }
   TranslateRect();
@@ -194,7 +253,12 @@ bool DxgiDuplicatorController::DoInitialize() {
   }
 
   identity_++;
-  return true;
+
+  if (duplicators_.empty()) {
+    LOG(LS_WARNING) << "Cannot initialize any DxgiAdapterDuplicator instance.";
+  }
+
+  return !duplicators_.empty();
 }
 
 void DxgiDuplicatorController::Deinitialize() {