Revert 116724 - Add gamepad data fetcher for Linux

content/browser/gamepad/platform_data_fetcher_linux.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 "content/browser/gamepad/platform_data_fetcher_linux.h"
-
-#include <dlfcn.h>
-#include <fcntl.h>
-#include <libudev.h>
-#include <linux/joystick.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#include "base/debug/trace_event.h"
-#include "base/eintr_wrapper.h"
-#include "base/message_loop.h"
-#include "base/string_number_conversions.h"
-#include "base/stringprintf.h"
-#include "base/string_util.h"
-#include "base/utf_string_conversions.h"
-#include "content/common/gamepad_hardware_buffer.h"
-
-namespace content {
-
-using WebKit::WebGamepad;
-using WebKit::WebGamepads;
-
-GamepadPlatformDataFetcherLinux::GamepadPlatformDataFetcherLinux() {
-  for (size_t i = 0; i < arraysize(device_fds_); ++i)
-    device_fds_[i] = -1;
-
-  udev_ = udev_new();
-
-  monitor_ = udev_monitor_new_from_netlink(udev_, "udev");
-  udev_monitor_filter_add_match_subsystem_devtype(monitor_, "input", NULL);
-  udev_monitor_enable_receiving(monitor_);
-  monitor_fd_ = udev_monitor_get_fd(monitor_);
-  MessageLoopForIO::current()->WatchFileDescriptor(monitor_fd_, true,
-      MessageLoopForIO::WATCH_READ, &monitor_watcher_, this);
-
-  EnumerateDevices();
-}
-
-GamepadPlatformDataFetcherLinux::~GamepadPlatformDataFetcherLinux() {
-  monitor_watcher_.StopWatchingFileDescriptor();
-  udev_unref(udev_);
-  for (size_t i = 0; i < WebGamepads::itemsLengthCap; ++i) {
-    if (device_fds_[i] >= 0)
-      close(device_fds_[i]);
-  }
-}
-
-void GamepadPlatformDataFetcherLinux::GetGamepadData(WebGamepads* pads, bool) {
-  TRACE_EVENT0("GAMEPAD", "GetGamepadData");
-
-  data_.length = WebGamepads::itemsLengthCap;
-
-  // Update our internal state.
-  for (size_t i = 0; i < WebGamepads::itemsLengthCap; ++i) {
-    if (device_fds_[i] >= 0) {
-      ReadDeviceData(i);
-    }
-  }
-
-  // Copy to the current state to the output buffer, using the mapping
-  // function, if there is one available.
-  pads->length = data_.length;
-  for (size_t i = 0; i < WebGamepads::itemsLengthCap; ++i) {
-    if (mappers_[i])
-      mappers_[i](data_.items[i], &pads->items[i]);
-    else
-      pads->items[i] = data_.items[i];
-  }
-}
-
-void GamepadPlatformDataFetcherLinux::OnFileCanReadWithoutBlocking(int fd) {
-  // Events occur when devices attached to the system are added, removed, or
-  // change state. udev_monitor_receive_device() will return a device object
-  // representing the device which changed and what type of change occured.
-  DCHECK(monitor_fd_ == fd);
-  udev_device* dev = udev_monitor_receive_device(monitor_);
-  RefreshDevice(dev);
-  udev_device_unref(dev);
-}
-
-void GamepadPlatformDataFetcherLinux::OnFileCanWriteWithoutBlocking(int fd) {
-}
-
-bool GamepadPlatformDataFetcherLinux::IsGamepad(
-    udev_device* dev,
-    int& index,
-    std::string& path) {
-  if (!udev_device_get_property_value(dev, "ID_INPUT_JOYSTICK"))
-    return false;
-
-  const char* node_path = udev_device_get_devnode(dev);
-  if (!node_path)
-    return false;
-
-  static const char kJoystickRoot[] = "/dev/input/js";
-  bool is_gamepad =
-      strncmp(kJoystickRoot, node_path, sizeof(kJoystickRoot) - 1) == 0;
-  if (is_gamepad) {
-    const int base_len = sizeof(kJoystickRoot) - 1;
-    if (!base::StringToInt(base::StringPiece(
-            &node_path[base_len],
-            strlen(node_path) - base_len),
-        &index))
-      return false;
-    if (index < 0 || index >= static_cast<int>(WebGamepads::itemsLengthCap))
-      return false;
-    path = std::string(node_path);
-  }
-  return is_gamepad;
-}
-
-// Used during enumeration, and monitor notifications.
-void GamepadPlatformDataFetcherLinux::RefreshDevice(udev_device* dev) {
-  int index;
-  std::string node_path;
-  if (IsGamepad(dev, index, node_path)) {
-    int& device_fd = device_fds_[index];
-    WebGamepad& pad = data_.items[index];
-    GamepadStandardMappingFunction& mapper = mappers_[index];
-
-    if (device_fd >= 0)
-      close(device_fd);
-
-    // The device pointed to by dev contains information about the input
-    // device. In order to get the information about the USB device, get the
-    // parent device with the subsystem/devtype pair of "usb"/"usb_device".
-    // This function walks up the tree several levels.
-    dev = udev_device_get_parent_with_subsystem_devtype(
-        dev,
-        "usb",
-        "usb_device");
-    if (!dev) {
-      // Unable to get device information, don't use this device.
-      device_fd = -1;
-      pad.connected = false;
-      return;
-    }
-
-    device_fd = HANDLE_EINTR(open(node_path.c_str(), O_RDONLY | O_NONBLOCK));
-    if (device_fd < 0) {
-      // Unable to open device, don't use.
-      pad.connected = false;
-      return;
-    }
-
-    const char* vendor_id = udev_device_get_sysattr_value(dev, "idVendor");
-    const char* product_id = udev_device_get_sysattr_value(dev, "idProduct");
-    mapper = GetGamepadStandardMappingFunction(vendor_id, product_id);
-
-    const char* manufacturer =
-        udev_device_get_sysattr_value(dev, "manufacturer");
-    const char* product = udev_device_get_sysattr_value(dev, "product");
-
-    // Driver returns utf-8 strings here, so combine in utf-8 and then convert
-    // to WebUChar to build the id string.
-    std::string id;
-    if (mapper) {
-      id = base::StringPrintf("%s %s (STANDARD GAMEPAD)",
-          manufacturer,
-          product);
-    } else {
-      id = base::StringPrintf("%s %s (Vendor: %s Product: %s)",
-          manufacturer,
-          product,
-          vendor_id,
-          product_id);
-    }
-    TruncateUTF8ToByteSize(id, WebGamepad::idLengthCap - 1, &id);
-    string16 tmp16 = UTF8ToUTF16(id);
-    memset(pad.id, 0, sizeof(pad.id));
-    tmp16.copy(pad.id, arraysize(pad.id) - 1);
-
-    pad.connected = true;
-  }
-}
-
-void GamepadPlatformDataFetcherLinux::EnumerateDevices() {
-  udev_enumerate* enumerate = udev_enumerate_new(udev_);
-  udev_enumerate_add_match_subsystem(enumerate, "input");
-  udev_enumerate_scan_devices(enumerate);
-
-  udev_list_entry* devices = udev_enumerate_get_list_entry(enumerate);
-  for (udev_list_entry* dev_list_entry = devices;
-       dev_list_entry != NULL;
-       dev_list_entry = udev_list_entry_get_next(dev_list_entry)) {
-    // Get the filename of the /sys entry for the device and create a
-    // udev_device object (dev) representing it
-    const char* path = udev_list_entry_get_name(dev_list_entry);
-    udev_device* dev = udev_device_new_from_syspath(udev_, path);
-    RefreshDevice(dev);
-    udev_device_unref(dev);
-  }
-  // Free the enumerator object
-  udev_enumerate_unref(enumerate);
-}
-
-void GamepadPlatformDataFetcherLinux::ReadDeviceData(size_t index) {
-  int& fd = device_fds_[index];
-  WebGamepad& pad = data_.items[index];
-  DCHECK(fd >= 0);
-
-  js_event event;
-  while (HANDLE_EINTR(read(fd, &event, sizeof(struct js_event)) > 0)) {
-    size_t item = event.number;
-    if (event.type & JS_EVENT_AXIS) {
-      if (item >= WebGamepad::axesLengthCap)
-        continue;
-      pad.axes[item] = event.value / 32767.f;
-      if (item >= pad.axesLength)
-        pad.axesLength = item + 1;
-    } else if (event.type & JS_EVENT_BUTTON) {
-      if (item >= WebGamepad::buttonsLengthCap)
-        continue;
-      pad.buttons[item] = event.value ? 1.0 : 0.0;
-      if (item >= pad.buttonsLength)
-        pad.buttonsLength = item + 1;
-    }
-    pad.timestamp = event.time;
-  }
-}
-
-
-}  // namespace content