michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * LinuxGamepadService: A Linux backend for the GamepadService.
michael@0:  * Derived from the kernel documentation at
michael@0:  * http://www.kernel.org/doc/Documentation/input/joystick-api.txt
michael@0:  */
michael@0: #include <algorithm>
michael@0: #include <cstddef>
michael@0: 
michael@0: #include <glib.h>
michael@0: #include <linux/joystick.h>
michael@0: #include <stdio.h>
michael@0: #include <stdint.h>
michael@0: #include <sys/ioctl.h>
michael@0: #include <unistd.h>
michael@0: 
michael@0: #include "nscore.h"
michael@0: #include "mozilla/dom/GamepadService.h"
michael@0: #include "udev.h"
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: using mozilla::dom::GamepadService;
michael@0: using mozilla::udev_lib;
michael@0: using mozilla::udev_device;
michael@0: using mozilla::udev_list_entry;
michael@0: using mozilla::udev_enumerate;
michael@0: using mozilla::udev_monitor;
michael@0: 
michael@0: static const float kMaxAxisValue = 32767.0;
michael@0: static const char kJoystickPath[] = "/dev/input/js";
michael@0: 
michael@0: //TODO: should find a USB identifier for each device so we can
michael@0: // provide something that persists across connect/disconnect cycles.
michael@0: typedef struct {
michael@0:   int index;
michael@0:   guint source_id;
michael@0:   int numAxes;
michael@0:   int numButtons;
michael@0:   char idstring[128];
michael@0:   char devpath[PATH_MAX];
michael@0: } Gamepad;
michael@0: 
michael@0: class LinuxGamepadService {
michael@0: public:
michael@0:   LinuxGamepadService() : mMonitor(nullptr),
michael@0:                           mMonitorSourceID(0) {
michael@0:   }
michael@0: 
michael@0:   void Startup();
michael@0:   void Shutdown();
michael@0: 
michael@0: private:
michael@0:   void AddDevice(struct udev_device* dev);
michael@0:   void RemoveDevice(struct udev_device* dev);
michael@0:   void ScanForDevices();
michael@0:   void AddMonitor();
michael@0:   void RemoveMonitor();
michael@0:   bool is_gamepad(struct udev_device* dev);
michael@0:   void ReadUdevChange();
michael@0: 
michael@0:   // handler for data from /dev/input/jsN
michael@0:   static gboolean OnGamepadData(GIOChannel *source,
michael@0:                                 GIOCondition condition,
michael@0:                                 gpointer data);
michael@0: 
michael@0:   // handler for data from udev monitor
michael@0:   static gboolean OnUdevMonitor(GIOChannel *source,
michael@0:                                 GIOCondition condition,
michael@0:                                 gpointer data);
michael@0: 
michael@0:   udev_lib mUdev;
michael@0:   struct udev_monitor* mMonitor;
michael@0:   guint mMonitorSourceID;
michael@0:   // Information about currently connected gamepads.
michael@0:   nsAutoTArray<Gamepad,4> mGamepads;
michael@0: };
michael@0: 
michael@0: // singleton instance
michael@0: LinuxGamepadService* gService = nullptr;
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::AddDevice(struct udev_device* dev)
michael@0: {
michael@0:   const char* devpath = mUdev.udev_device_get_devnode(dev);
michael@0:   if (!devpath) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // Ensure that this device hasn't already been added.
michael@0:   for (unsigned int i = 0; i < mGamepads.Length(); i++) {
michael@0:     if (strcmp(mGamepads[i].devpath, devpath) == 0) {
michael@0:       return;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   Gamepad gamepad;
michael@0:   snprintf(gamepad.devpath, sizeof(gamepad.devpath), "%s", devpath);
michael@0:   GIOChannel* channel = g_io_channel_new_file(devpath, "r", nullptr);
michael@0:   if (!channel) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   g_io_channel_set_flags(channel, G_IO_FLAG_NONBLOCK, nullptr);
michael@0:   g_io_channel_set_encoding(channel, nullptr, nullptr);
michael@0:   g_io_channel_set_buffered(channel, FALSE);
michael@0:   int fd = g_io_channel_unix_get_fd(channel);
michael@0:   char name[128];
michael@0:   if (ioctl(fd, JSIOCGNAME(sizeof(name)), &name) == -1) {
michael@0:     strcpy(name, "unknown");
michael@0:   }
michael@0:   const char* vendor_id =
michael@0:     mUdev.udev_device_get_property_value(dev, "ID_VENDOR_ID");
michael@0:   const char* model_id =
michael@0:     mUdev.udev_device_get_property_value(dev, "ID_MODEL_ID");
michael@0:   if (!vendor_id || !model_id) {
michael@0:     struct udev_device* parent =
michael@0:       mUdev.udev_device_get_parent_with_subsystem_devtype(dev,
michael@0:                                                           "input",
michael@0:                                                           nullptr);
michael@0:     if (parent) {
michael@0:       vendor_id = mUdev.udev_device_get_sysattr_value(parent, "id/vendor");
michael@0:       model_id = mUdev.udev_device_get_sysattr_value(parent, "id/product");
michael@0:     }
michael@0:   }
michael@0:   snprintf(gamepad.idstring, sizeof(gamepad.idstring),
michael@0:            "%s-%s-%s",
michael@0:            vendor_id ? vendor_id : "unknown",
michael@0:            model_id ? model_id : "unknown",
michael@0:            name);
michael@0: 
michael@0:   char numAxes = 0, numButtons = 0;
michael@0:   ioctl(fd, JSIOCGAXES, &numAxes);
michael@0:   gamepad.numAxes = numAxes;
michael@0:   ioctl(fd, JSIOCGBUTTONS, &numButtons);
michael@0:   gamepad.numButtons = numButtons;
michael@0: 
michael@0:   nsRefPtr<GamepadService> service(GamepadService::GetService());
michael@0:   gamepad.index = service->AddGamepad(gamepad.idstring,
michael@0:                                       mozilla::dom::NoMapping,
michael@0:                                       gamepad.numButtons,
michael@0:                                       gamepad.numAxes);
michael@0: 
michael@0:   gamepad.source_id =
michael@0:     g_io_add_watch(channel,
michael@0:                    GIOCondition(G_IO_IN | G_IO_ERR | G_IO_HUP),
michael@0:                    OnGamepadData,
michael@0:                    GINT_TO_POINTER(gamepad.index));
michael@0:   g_io_channel_unref(channel);
michael@0: 
michael@0:   mGamepads.AppendElement(gamepad);
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::RemoveDevice(struct udev_device* dev)
michael@0: {
michael@0:   const char* devpath = mUdev.udev_device_get_devnode(dev);
michael@0:   if (!devpath) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   nsRefPtr<GamepadService> service(GamepadService::GetService());
michael@0:   for (unsigned int i = 0; i < mGamepads.Length(); i++) {
michael@0:     if (strcmp(mGamepads[i].devpath, devpath) == 0) {
michael@0:       g_source_remove(mGamepads[i].source_id);
michael@0:       service->RemoveGamepad(mGamepads[i].index);
michael@0:       mGamepads.RemoveElementAt(i);
michael@0:       break;
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::ScanForDevices()
michael@0: {
michael@0:   struct udev_enumerate* en = mUdev.udev_enumerate_new(mUdev.udev);
michael@0:   mUdev.udev_enumerate_add_match_subsystem(en, "input");
michael@0:   mUdev.udev_enumerate_scan_devices(en);
michael@0: 
michael@0:   struct udev_list_entry* dev_list_entry;
michael@0:   for (dev_list_entry = mUdev.udev_enumerate_get_list_entry(en);
michael@0:        dev_list_entry != nullptr;
michael@0:        dev_list_entry = mUdev.udev_list_entry_get_next(dev_list_entry)) {
michael@0:     const char* path = mUdev.udev_list_entry_get_name(dev_list_entry);
michael@0:     struct udev_device* dev = mUdev.udev_device_new_from_syspath(mUdev.udev,
michael@0:                                                                  path);
michael@0:     if (is_gamepad(dev)) {
michael@0:       AddDevice(dev);
michael@0:     }
michael@0: 
michael@0:     mUdev.udev_device_unref(dev);
michael@0:   }
michael@0: 
michael@0:   mUdev.udev_enumerate_unref(en);
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::AddMonitor()
michael@0: {
michael@0:   // Add a monitor to watch for device changes
michael@0:   mMonitor =
michael@0:     mUdev.udev_monitor_new_from_netlink(mUdev.udev, "udev");
michael@0:   if (!mMonitor) {
michael@0:     // Not much we can do here.
michael@0:     return;
michael@0:   }
michael@0:   mUdev.udev_monitor_filter_add_match_subsystem_devtype(mMonitor,
michael@0:                                                         "input",
michael@0: 							nullptr);
michael@0: 
michael@0:   int monitor_fd = mUdev.udev_monitor_get_fd(mMonitor);
michael@0:   GIOChannel* monitor_channel = g_io_channel_unix_new(monitor_fd);
michael@0:   mMonitorSourceID =
michael@0:     g_io_add_watch(monitor_channel,
michael@0:                    GIOCondition(G_IO_IN | G_IO_ERR | G_IO_HUP),
michael@0:                    OnUdevMonitor,
michael@0:                    nullptr);
michael@0:   g_io_channel_unref(monitor_channel);
michael@0: 
michael@0:   mUdev.udev_monitor_enable_receiving(mMonitor);
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::RemoveMonitor()
michael@0: {
michael@0:   if (mMonitorSourceID) {
michael@0:     g_source_remove(mMonitorSourceID);
michael@0:     mMonitorSourceID = 0;
michael@0:   }
michael@0:   if (mMonitor) {
michael@0:     mUdev.udev_monitor_unref(mMonitor);
michael@0:     mMonitor = nullptr;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::Startup()
michael@0: {
michael@0:   // Don't bother starting up if libudev couldn't be loaded or initialized.
michael@0:   if (!mUdev)
michael@0:     return;
michael@0: 
michael@0:   AddMonitor();
michael@0:   ScanForDevices();
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::Shutdown()
michael@0: {
michael@0:   for (unsigned int i = 0; i < mGamepads.Length(); i++) {
michael@0:     g_source_remove(mGamepads[i].source_id);
michael@0:   }
michael@0:   mGamepads.Clear();
michael@0:   RemoveMonitor();
michael@0: }
michael@0: 
michael@0: bool
michael@0: LinuxGamepadService::is_gamepad(struct udev_device* dev)
michael@0: {
michael@0:   if (!mUdev.udev_device_get_property_value(dev, "ID_INPUT_JOYSTICK"))
michael@0:     return false;
michael@0: 
michael@0:   const char* devpath = mUdev.udev_device_get_devnode(dev);
michael@0:   if (!devpath) {
michael@0:     return false;
michael@0:   }
michael@0:   if (strncmp(kJoystickPath, devpath, sizeof(kJoystickPath) - 1) != 0) {
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: void
michael@0: LinuxGamepadService::ReadUdevChange()
michael@0: {
michael@0:   struct udev_device* dev =
michael@0:     mUdev.udev_monitor_receive_device(mMonitor);
michael@0:   const char* action = mUdev.udev_device_get_action(dev);
michael@0:   if (is_gamepad(dev)) {
michael@0:     if (strcmp(action, "add") == 0) {
michael@0:       AddDevice(dev);
michael@0:     } else if (strcmp(action, "remove") == 0) {
michael@0:       RemoveDevice(dev);
michael@0:     }
michael@0:   }
michael@0:   mUdev.udev_device_unref(dev);
michael@0: }
michael@0: 
michael@0: // static
michael@0: gboolean
michael@0: LinuxGamepadService::OnGamepadData(GIOChannel* source,
michael@0:                                    GIOCondition condition,
michael@0:                                    gpointer data)
michael@0: {
michael@0:   int index = GPOINTER_TO_INT(data);
michael@0:   //TODO: remove gamepad?
michael@0:   if (condition & G_IO_ERR || condition & G_IO_HUP)
michael@0:     return FALSE;
michael@0: 
michael@0:   while (true) {
michael@0:     struct js_event event;
michael@0:     gsize count;
michael@0:     GError* err = nullptr;
michael@0:     if (g_io_channel_read_chars(source,
michael@0: 				(gchar*)&event,
michael@0: 				sizeof(event),
michael@0: 				&count,
michael@0: 				&err) != G_IO_STATUS_NORMAL ||
michael@0: 	count == 0) {
michael@0:       break;
michael@0:     }
michael@0: 
michael@0:     //TODO: store device state?
michael@0:     if (event.type & JS_EVENT_INIT) {
michael@0:       continue;
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<GamepadService> service(GamepadService::GetService());
michael@0:     switch (event.type) {
michael@0:     case JS_EVENT_BUTTON:
michael@0:       service->NewButtonEvent(index, event.number, !!event.value);
michael@0:       break;
michael@0:     case JS_EVENT_AXIS:
michael@0:       service->NewAxisMoveEvent(index, event.number,
michael@0:                                 ((float)event.value) / kMaxAxisValue);
michael@0:       break;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   return TRUE;
michael@0: }
michael@0: 
michael@0: // static
michael@0: gboolean
michael@0: LinuxGamepadService::OnUdevMonitor(GIOChannel* source,
michael@0:                                    GIOCondition condition,
michael@0:                                    gpointer data)
michael@0: {
michael@0:   if (condition & G_IO_ERR || condition & G_IO_HUP)
michael@0:     return FALSE;
michael@0: 
michael@0:   gService->ReadUdevChange();
michael@0:   return TRUE;
michael@0: }
michael@0: 
michael@0: } // namespace
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace hal_impl {
michael@0: 
michael@0: void StartMonitoringGamepadStatus()
michael@0: {
michael@0:   if (!gService) {
michael@0:     gService = new LinuxGamepadService();
michael@0:     gService->Startup();
michael@0:   }
michael@0: }
michael@0: 
michael@0: void StopMonitoringGamepadStatus()
michael@0: {
michael@0:   if (gService) {
michael@0:     gService->Shutdown();
michael@0:     delete gService;
michael@0:     gService = nullptr;
michael@0:   }
michael@0: }
michael@0: 
michael@0: } // namespace hal_impl
michael@0: } // namespace mozilla