Move touchscreen_util.cc/h from ash to ui.

ash/touch/touchscreen_util.cc

-// Copyright 2014 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 "ash/touch/touchscreen_util.h"
-
-#include <set>
-
-#include "base/files/file_util.h"
-#include "base/logging.h"
-#include "base/strings/string_util.h"
-#include "ui/events/devices/input_device.h"
-
-namespace ash {
-
-namespace {
-
-using DisplayInfoList = std::vector<display::ManagedDisplayInfo*>;
-using DeviceList = std::vector<const ui::TouchscreenDevice*>;
-
-// Helper method to associate |display| and |device|.
-void Associate(display::ManagedDisplayInfo* display,
-               const ui::TouchscreenDevice* device) {
-  display->AddInputDevice(device->id);
-  display->set_touch_support(display::Display::TOUCH_SUPPORT_AVAILABLE);
-}
-
-// Returns true if |path| is likely a USB device.
-bool IsDeviceConnectedViaUsb(const base::FilePath& path) {
-  std::vector<base::FilePath::StringType> components;
-  path.GetComponents(&components);
-
-  for (const auto& component : components) {
-    if (base::StartsWith(component, "usb",
-                         base::CompareCase::INSENSITIVE_ASCII))
-      return true;
-  }
-
-  return false;
-}
-
-// Returns the UDL association score between |display| and |device|. A score <=
-// 0 means that there is no association.
-int GetUdlAssociationScore(const display::ManagedDisplayInfo* display,
-                           const ui::TouchscreenDevice* device) {
-  // If the devices are not both connected via USB, then there cannot be a UDL
-  // association score.
-  if (!IsDeviceConnectedViaUsb(display->sys_path()) ||
-      !IsDeviceConnectedViaUsb(device->sys_path))
-    return 0;
-
-  // The association score is simply the number of prefix path components that
-  // sysfs paths have in common.
-  std::vector<base::FilePath::StringType> display_components;
-  std::vector<base::FilePath::StringType> device_components;
-  display->sys_path().GetComponents(&display_components);
-  device->sys_path.GetComponents(&device_components);
-
-  std::size_t largest_idx = 0;
-  while (largest_idx < display_components.size() &&
-         largest_idx < device_components.size() &&
-         display_components[largest_idx] == device_components[largest_idx]) {
-    ++largest_idx;
-  }
-  return largest_idx;
-}
-
-// Tries to find a UDL device that best matches |display|. Returns nullptr
-// if one is not found.
-const ui::TouchscreenDevice* GuessBestUdlDevice(
-    const display::ManagedDisplayInfo* display,
-    const DeviceList& devices) {
-  int best_score = 0;
-  const ui::TouchscreenDevice* best_device = nullptr;
-
-  for (const ui::TouchscreenDevice* device : devices) {
-    int score = GetUdlAssociationScore(display, device);
-    if (score > best_score) {
-      best_score = score;
-      best_device = device;
-    }
-  }
-
-  return best_device;
-}
-
-void AssociateUdlDevices(DisplayInfoList* displays, DeviceList* devices) {
-  VLOG(2) << "Trying to match udl devices (" << displays->size()
-          << " displays and " << devices->size() << " devices to match)";
-
-  DisplayInfoList::iterator display_it = displays->begin();
-  while (display_it != displays->end()) {
-    display::ManagedDisplayInfo* display = *display_it;
-    const ui::TouchscreenDevice* device = GuessBestUdlDevice(display, *devices);
-
-    if (device) {
-      VLOG(2) << "=> Matched device " << device->name << " to display "
-              << display->name()
-              << " (score=" << GetUdlAssociationScore(display, device) << ")";
-      Associate(display, device);
-
-      display_it = displays->erase(display_it);
-      devices->erase(std::find(devices->begin(), devices->end(), device));
-
-      continue;
-    }
-
-    ++display_it;
-  }
-}
-
-// Returns true if |display| is internal.
-bool IsInternalDisplay(const display::ManagedDisplayInfo* display) {
-  return display::Display::IsInternalDisplayId(display->id());
-}
-
-// Returns true if |device| is internal.
-bool IsInternalDevice(const ui::TouchscreenDevice* device) {
-  return device->type == ui::InputDeviceType::INPUT_DEVICE_INTERNAL;
-}
-
-void AssociateInternalDevices(DisplayInfoList* displays, DeviceList* devices) {
-  VLOG(2) << "Trying to match internal devices (" << displays->size()
-          << " displays and " << devices->size() << " devices to match)";
-
-  // Internal device assocation has a couple of gotchas:
-  // - There can be internal devices but no internal display, or visa-versa.
-  // - There can be multiple internal devices matching one internal display. We
-  //   assume there is at most one internal display.
-  // - All internal devices must be removed from |displays| and |devices| after
-  //   this function has returned, since an internal device can never be
-  //   associated with an external device.
-
-  // Capture the internal display reference as we remove it from |displays|.
-  display::ManagedDisplayInfo* internal_display = nullptr;
-  DisplayInfoList::iterator display_it =
-      std::find_if(displays->begin(), displays->end(), &IsInternalDisplay);
-  if (display_it != displays->end()) {
-    internal_display = *display_it;
-    displays->erase(display_it);
-  }
-
-  bool matched = false;
-
-  // Remove all internal devices from |devices|. If we have an internal display,
-  // then associate the device with the display before removing it.
-  DeviceList::iterator device_it = devices->begin();
-  while (device_it != devices->end()) {
-    const ui::TouchscreenDevice* internal_device = *device_it;
-
-    // Not an internal device, skip it.
-    if (!IsInternalDevice(internal_device)) {
-      ++device_it;
-      continue;
-    }
-
-    if (internal_display) {
-      VLOG(2) << "=> Matched device " << internal_device->name << " to display "
-              << internal_display->name();
-      Associate(internal_display, internal_device);
-      matched = true;
-    } else {
-      VLOG(2) << "=> Removing internal device " << internal_device->name;
-    }
-
-    device_it = devices->erase(device_it);
-  }
-
-  if (!matched && internal_display)
-    VLOG(2) << "=> Removing internal display " << internal_display->name();
-}
-
-void AssociateSameSizeDevices(DisplayInfoList* displays, DeviceList* devices) {
-  // Associate screens/displays with the same size.
-  VLOG(2) << "Trying to match same-size devices (" << displays->size()
-          << " displays and " << devices->size() << " devices to match)";
-
-  DisplayInfoList::iterator display_it = displays->begin();
-  while (display_it != displays->end()) {
-    display::ManagedDisplayInfo* display = *display_it;
-    const gfx::Size native_size = display->GetNativeModeSize();
-
-    // Try to find an input device with roughly the same size as the display.
-    DeviceList::iterator device_it = std::find_if(
-        devices->begin(), devices->end(),
-        [&native_size](const ui::TouchscreenDevice* device) {
-          // Allow 1 pixel difference between screen and touchscreen
-          // resolutions. Because in some cases for monitor resolution
-          // 1024x768 touchscreen's resolution would be 1024x768, but for
-          // some 1023x767. It really depends on touchscreen's firmware
-          // configuration.
-          return std::abs(native_size.width() - device->size.width()) <= 1 &&
-                 std::abs(native_size.height() - device->size.height()) <= 1;
-        });
-
-    if (device_it != devices->end()) {
-      const ui::TouchscreenDevice* device = *device_it;
-      VLOG(2) << "=> Matched device " << device->name << " to display "
-              << display->name() << " (display_size: " << native_size.ToString()
-              << ", device_size: " << device->size.ToString() << ")";
-      Associate(display, device);
-
-      display_it = displays->erase(display_it);
-      device_it = devices->erase(device_it);
-      continue;
-    }
-
-    // Didn't find an input device. Skip this display.
-    ++display_it;
-  }
-}
-
-void AssociateToSingleDisplay(DisplayInfoList* displays, DeviceList* devices) {
-  // If there is only one display left, then we should associate all input
-  // devices with it.
-
-  VLOG(2) << "Trying to match to single display (" << displays->size()
-          << " displays and " << devices->size() << " devices to match)";
-
-  // We only associate to one display.
-  if (displays->size() != 1 || devices->empty())
-    return;
-
-  display::ManagedDisplayInfo* display = *displays->begin();
-  for (const ui::TouchscreenDevice* device : *devices) {
-    VLOG(2) << "=> Matched device " << device->name << " to display "
-            << display->name();
-    Associate(display, device);
-  }
-
-  displays->clear();
-  devices->clear();
-}
-
-}  // namespace
-
-void AssociateTouchscreens(
-    std::vector<display::ManagedDisplayInfo>* all_displays,
-    const std::vector<ui::TouchscreenDevice>& all_devices) {
-  // |displays| and |devices| contain pointers directly to the values stored
-  // inside of |all_displays| and |all_devices|. When a display or input device
-  // has been associated, it is removed from the |displays| or |devices| list.
-
-  // Construct our initial set of display/devices that we will process.
-  DisplayInfoList displays;
-  for (display::ManagedDisplayInfo& display : *all_displays) {
-    display.ClearInputDevices();
-
-    if (display.GetNativeModeSize().IsEmpty()) {
-      VLOG(2) << "Will not match display " << display.id()
-              << " since it doesn't have a native mode";
-      continue;
-    }
-    displays.push_back(&display);
-  }
-
-  // Construct initial set of devices.
-  DeviceList devices;
-  for (const ui::TouchscreenDevice& device : all_devices)
-    devices.push_back(&device);
-
-  for (const display::ManagedDisplayInfo* display : displays) {
-    VLOG(2) << "Received display " << display->name()
-            << " (size: " << display->GetNativeModeSize().ToString()
-            << ", sys_path: " << display->sys_path().LossyDisplayName() << ")";
-  }
-  for (const ui::TouchscreenDevice* device : devices) {
-    VLOG(2) << "Received device " << device->name
-            << " (size: " << device->size.ToString()
-            << ", sys_path: " << device->sys_path.LossyDisplayName() << ")";
-  }
-
-  AssociateInternalDevices(&displays, &devices);
-  AssociateUdlDevices(&displays, &devices);
-  AssociateSameSizeDevices(&displays, &devices);
-  AssociateToSingleDisplay(&displays, &devices);
-
-  for (const display::ManagedDisplayInfo* display : displays)
-    LOG(WARNING) << "Unmatched display " << display->name();
-  for (const ui::TouchscreenDevice* device : devices)
-    LOG(WARNING) << "Unmatched device " << device->name;
-}
-
-}  // namespace ash