Prepare SyntheticPointerAction to handle touch actions for multiple fingers

content/browser/renderer_host/input/synthetic_pointer_action.cc

 // Copyright 2015 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 "content/browser/renderer_host/input/synthetic_pointer_action.h"
 
 #include "base/logging.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "ui/events/latency_info.h"
 
 namespace content {
 
+using blink::WebTouchEvent;
+
 SyntheticPointerAction::SyntheticPointerAction(
     const SyntheticPointerActionParams& params)
     : params_(params) {}
 
 SyntheticPointerAction::SyntheticPointerAction(
-    const SyntheticPointerActionParams& params,
-    SyntheticPointer* synthetic_pointer)
-    : params_(params), synthetic_pointer_(synthetic_pointer) {}
+    const std::vector<SyntheticPointerActionParams>& param_list,
+    SyntheticPointer* synthetic_pointer,
+    int* index_map)
+    : param_list_(param_list),
+      synthetic_pointer_(synthetic_pointer),
+      index_map_(index_map) {}
 
 SyntheticPointerAction::~SyntheticPointerAction() {}
 
 SyntheticGesture::Result SyntheticPointerAction::ForwardInputEvents(
     const base::TimeTicks& timestamp,
     SyntheticGestureTarget* target) {
+  LOG(ERROR) << "SyntheticPointerAction::ForwardInputEvents ";
   if (params_.gesture_source_type == SyntheticGestureParams::DEFAULT_INPUT)
     params_.gesture_source_type =
         target->GetDefaultSyntheticGestureSourceType();
 
   DCHECK_NE(params_.gesture_source_type, SyntheticGestureParams::DEFAULT_INPUT);
+  DCHECK(synthetic_pointer_);
 
   ForwardTouchOrMouseInputEvents(timestamp, target);
   return SyntheticGesture::GESTURE_FINISHED;
 }
 
 void SyntheticPointerAction::ForwardTouchOrMouseInputEvents(
     const base::TimeTicks& timestamp,
     SyntheticGestureTarget* target) {
-  switch (params_.pointer_action_type()) {
-    case SyntheticPointerActionParams::PointerActionType::PRESS:
-      synthetic_pointer_->Press(params_.position().x(), params_.position().y(),
-                                target, timestamp);
-      break;
-    case SyntheticPointerActionParams::PointerActionType::MOVE:
-      synthetic_pointer_->Move(params_.index(), params_.position().x(),
-                               params_.position().y(), target, timestamp);
-      break;
-    case SyntheticPointerActionParams::PointerActionType::RELEASE:
-      synthetic_pointer_->Release(params_.index(), target, timestamp);
-      break;
-    default:
-      NOTREACHED();
-      break;
+  LOG(ERROR) << "SyntheticPointerAction::ForwardTouchOrMouseInputEvents "
+             << param_list_.size();
+  if (param_list_.size() == 0)
+    return;
+
+  for (auto iter = param_list_.begin(); iter != param_list_.end(); ++iter) {
+    SyntheticPointerActionParams params = (*iter);

[tdresser, 2016/04/18 15:24:39]

() aren't needed.

+    CHECK_GE(params.index(), 0);
+    CHECK_LT(params.index(), WebTouchEvent::touchesLengthCap);
+    switch (params.pointer_action_type()) {
+      case SyntheticPointerActionParams::PointerActionType::PRESS: {
+        int index = synthetic_pointer_->Press(
+            params.position().x(), params.position().y(), target, timestamp);
+        index_map_[params.index()] = index;

[tdresser, 2016/04/18 15:24:39]

Should we use a vector for index_map_? Somewhere we should validate that the
length is okay, which we can't do if we're passing a raw pointer.

[lanwei, 2016/04/19 19:05:32]

Yes, I was thinking about which one to choose, I felt an int pointer is easy to
use, but you are right, vector is safer.

+        break;
+      }
+      case SyntheticPointerActionParams::PointerActionType::MOVE:
+        CHECK_GE(index_map_[params.index()], 0);
+        CHECK_LT(index_map_[params.index()], WebTouchEvent::touchesLengthCap);
+        synthetic_pointer_->Move(index_map_[params.index()],
+                                 params.position().x(), params.position().y(),
+                                 target, timestamp);
+        break;
+      case SyntheticPointerActionParams::PointerActionType::RELEASE:
+        CHECK_GE(index_map_[params.index()], 0);
+        CHECK_LT(index_map_[params.index()], WebTouchEvent::touchesLengthCap);
+        synthetic_pointer_->Release(index_map_[params.index()], target,
+                                    timestamp);
+        break;
+      default:
+        NOTREACHED();
+        break;
+    }
   }
   synthetic_pointer_->DispatchEvent(target, timestamp);
 }
 
 }  // namespace content