RetroArch/input/dinput.c

/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 * 
 *  RetroArch is free software: you can redistribute it and/or modify it under the terms
 *  of the GNU General Public License as published by the Free Software Found-
 *  ation, either version 3 of the License, or (at your option) any later version.
 *
 *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 *  PURPOSE.  See the GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along with RetroArch.
 *  If not, see <http://www.gnu.org/licenses/>.
 */

#ifdef _MSC_VER
#pragma comment(lib, "dinput8")
#endif

#undef DIRECTINPUT_VERSION
#define DIRECTINPUT_VERSION 0x0800
#include <dinput.h>

#include "../general.h"
#include "../boolean.h"
#include "input_common.h"
#include "retroarch_logger.h"
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <windowsx.h>

/* Context has to be global as joypads also ride on this context. */
static LPDIRECTINPUT8 g_ctx;

struct pointer_status
{
   int pointer_id;
   int pointer_x;
   int pointer_y;
   struct pointer_status *next;
};

struct dinput_input
{
   LPDIRECTINPUTDEVICE8 keyboard;
   LPDIRECTINPUTDEVICE8 mouse;
   const rarch_joypad_driver_t *joypad;
   uint8_t state[256];

   int mouse_rel_x;
   int mouse_rel_y;
   int mouse_x;
   int mouse_y;
   bool mouse_l, mouse_r, mouse_m, mouse_wu, mouse_wd;
   struct pointer_status pointer_head;  /* dummy head for easier iteration */
};

struct dinput_joypad
{
   LPDIRECTINPUTDEVICE8 joypad;
   DIJOYSTATE2 joy_state;
   char* joy_name;
};

static unsigned g_joypad_cnt;
static struct dinput_joypad g_pads[MAX_PLAYERS];

static void dinput_destroy_context(void)
{
   if (g_ctx)
   {
      IDirectInput8_Release(g_ctx);
      g_ctx = NULL;
   }
}

static bool dinput_init_context(void)
{
   if (g_ctx)
      return true;

   CoInitialize(NULL);

   /* Who said we shouldn't have same call signature in a COM API? <_< */
#ifdef __cplusplus
   if (FAILED(DirectInput8Create(
      GetModuleHandle(NULL), DIRECTINPUT_VERSION, IID_IDirectInput8,
      (void**)&g_ctx, NULL)))
#else
   if (FAILED(DirectInput8Create(
      GetModuleHandle(NULL), DIRECTINPUT_VERSION, &IID_IDirectInput8,
      (void**)&g_ctx, NULL)))
#endif
   {
      RARCH_ERR("Failed to init DirectInput.\n");
      return false;
   }

   return true;
}

static void *dinput_init(void)
{
   if (!dinput_init_context())
   {
      RARCH_ERR("Failed to start DirectInput driver.\n");
      return NULL;
   }

   struct dinput_input *di = (struct dinput_input*)calloc(1, sizeof(*di));
   if (!di)
      return NULL;

#ifdef __cplusplus
   if (FAILED(IDirectInput8_CreateDevice(g_ctx, GUID_SysKeyboard, &di->keyboard, NULL)))
   {
      RARCH_ERR("Failed to create keyboard device.\n");
      di->keyboard = NULL;
   }

   if (FAILED(IDirectInput8_CreateDevice(g_ctx, GUID_SysMouse, &di->mouse, NULL)))
   {
      RARCH_ERR("Failed to create mouse device.\n");
      di->mouse = NULL;
   }
#else
   if (FAILED(IDirectInput8_CreateDevice(g_ctx, &GUID_SysKeyboard, &di->keyboard, NULL)))
   {
      RARCH_ERR("Failed to create keyboard device.\n");
      di->keyboard = NULL;
   }
   if (FAILED(IDirectInput8_CreateDevice(g_ctx, &GUID_SysMouse, &di->mouse, NULL)))
   {
      RARCH_ERR("Failed to create mouse device.\n");
      di->mouse = NULL;
   }
#endif

   if (di->keyboard)
   {
      IDirectInputDevice8_SetDataFormat(di->keyboard, &c_dfDIKeyboard);
      IDirectInputDevice8_SetCooperativeLevel(di->keyboard,
            (HWND)driver.video_window, DISCL_NONEXCLUSIVE | DISCL_FOREGROUND);
      IDirectInputDevice8_Acquire(di->keyboard);
   }

   if (di->mouse)
   {
      IDirectInputDevice8_SetDataFormat(di->mouse, &c_dfDIMouse2);
      IDirectInputDevice8_SetCooperativeLevel(di->mouse, (HWND)driver.video_window,
            DISCL_NONEXCLUSIVE | DISCL_FOREGROUND);
      IDirectInputDevice8_Acquire(di->mouse);
   }

   input_init_keyboard_lut(rarch_key_map_dinput);
   di->joypad = input_joypad_init_driver(g_settings.input.joypad_driver);

   return di;
}

static void dinput_poll(void *data)
{
   struct dinput_input *di = (struct dinput_input*)data;

   memset(di->state, 0, sizeof(di->state));
   if (di->keyboard)
   {
      if (FAILED(IDirectInputDevice8_GetDeviceState(
                  di->keyboard, sizeof(di->state), di->state)))
      {
         IDirectInputDevice8_Acquire(di->keyboard);
         if (FAILED(IDirectInputDevice8_GetDeviceState(
                     di->keyboard, sizeof(di->state), di->state)))
            memset(di->state, 0, sizeof(di->state));
      }
   }

   if (di->mouse)
   {
      DIMOUSESTATE2 mouse_state;
      memset(&mouse_state, 0, sizeof(mouse_state));

      if (FAILED(IDirectInputDevice8_GetDeviceState(
                  di->mouse, sizeof(mouse_state), &mouse_state)))
      {
         IDirectInputDevice8_Acquire(di->mouse);
         if (FAILED(IDirectInputDevice8_GetDeviceState(
                     di->mouse, sizeof(mouse_state), &mouse_state)))
            memset(&mouse_state, 0, sizeof(mouse_state));
      }

      di->mouse_rel_x = mouse_state.lX;
      di->mouse_rel_y = mouse_state.lY;
      di->mouse_l  = mouse_state.rgbButtons[0];
      di->mouse_r  = mouse_state.rgbButtons[1];
      di->mouse_m  = mouse_state.rgbButtons[2];
      di->mouse_wu = mouse_state.rgbButtons[3];
      di->mouse_wd = mouse_state.rgbButtons[4];

      /* No simple way to get absolute coordinates 
       * for RETRO_DEVICE_POINTER. Just use Win32 APIs. */
      POINT point = {0};
      GetCursorPos(&point);
      ScreenToClient((HWND)driver.video_window, &point);
      di->mouse_x = point.x;
      di->mouse_y = point.y;
   }

   if (di->joypad)
      di->joypad->poll();
}

static bool dinput_keyboard_pressed(struct dinput_input *di, unsigned key)
{
   if (key >= RETROK_LAST)
      return false;

   unsigned sym = input_translate_rk_to_keysym((enum retro_key)key);
   return di->state[sym] & 0x80;
}

static bool dinput_is_pressed(struct dinput_input *di,
      const struct retro_keybind *binds,
      unsigned port, unsigned id)
{
   if (id >= RARCH_BIND_LIST_END)
      return false;

   const struct retro_keybind *bind = &binds[id];
   return dinput_keyboard_pressed(di, bind->key) || 
      input_joypad_pressed(di->joypad, port, binds, id);
}

static int16_t dinput_pressed_analog(struct dinput_input *di,
      const struct retro_keybind *binds,
      unsigned index, unsigned id)
{
   unsigned id_minus = 0;
   unsigned id_plus  = 0;
   input_conv_analog_id_to_bind_id(index, id, &id_minus, &id_plus);

   const struct retro_keybind *bind_minus = &binds[id_minus];
   const struct retro_keybind *bind_plus  = &binds[id_plus];
   if (!bind_minus->valid || !bind_plus->valid)
      return 0;

   int16_t pressed_minus = 
      dinput_keyboard_pressed(di, bind_minus->key) ? -0x7fff : 0;
   int16_t pressed_plus = 
      dinput_keyboard_pressed(di, bind_plus->key) ? 0x7fff : 0;
   return pressed_plus + pressed_minus;
}

static bool dinput_key_pressed(void *data, int key)
{
   return dinput_is_pressed((struct dinput_input*)data,
         g_settings.input.binds[0], 0, key);
}

static int16_t dinput_lightgun_state(struct dinput_input *di, unsigned id)
{
   switch (id)
   {
      case RETRO_DEVICE_ID_LIGHTGUN_X:
         return di->mouse_rel_x;
      case RETRO_DEVICE_ID_LIGHTGUN_Y:
         return di->mouse_rel_y;
      case RETRO_DEVICE_ID_LIGHTGUN_TRIGGER:
         return di->mouse_l;
      case RETRO_DEVICE_ID_LIGHTGUN_CURSOR:
         return di->mouse_m;
      case RETRO_DEVICE_ID_LIGHTGUN_TURBO:
         return di->mouse_r;
      case RETRO_DEVICE_ID_LIGHTGUN_START:
         return di->mouse_m && di->mouse_r; 
      case RETRO_DEVICE_ID_LIGHTGUN_PAUSE:
         return di->mouse_m && di->mouse_l; 
   }

   return 0;
}

static int16_t dinput_mouse_state(struct dinput_input *di, unsigned id)
{
   switch (id)
   {
      case RETRO_DEVICE_ID_MOUSE_X:
         return di->mouse_rel_x;
      case RETRO_DEVICE_ID_MOUSE_Y:
         return di->mouse_rel_y;
      case RETRO_DEVICE_ID_MOUSE_LEFT:
         return di->mouse_l;
      case RETRO_DEVICE_ID_MOUSE_RIGHT:
         return di->mouse_r;
      case RETRO_DEVICE_ID_MOUSE_WHEELUP:
         return di->mouse_wu;
      case RETRO_DEVICE_ID_MOUSE_WHEELDOWN:
         return di->mouse_wd;
      case RETRO_DEVICE_ID_MOUSE_MIDDLE:
         return di->mouse_m;
   }

   return 0;
}

static int16_t dinput_pointer_state(struct dinput_input *di,
      unsigned index, unsigned id, bool screen)
{
   int16_t res_x = 0, res_y = 0, res_screen_x = 0, res_screen_y = 0;
   unsigned num = 0;
   struct pointer_status *check_pos = di->pointer_head.next;
   while (check_pos && num < index)
   {
      num++;
      check_pos = check_pos->next;
   }
   if (!check_pos && index > 0) /* index = 0 has mouse fallback. */
      return 0;

   int x = check_pos ? check_pos->pointer_x : di->mouse_x;
   int y = check_pos ? check_pos->pointer_y : di->mouse_y;
   bool pointer_down = check_pos ? true : di->mouse_l;

   bool valid = input_translate_coord_viewport(x, y,
         &res_x, &res_y, &res_screen_x, &res_screen_y);

   if (!valid)
      return 0;

   if (screen)
   {
      res_x = res_screen_x;
      res_y = res_screen_y;
   }

   bool inside = (res_x >= -0x7fff) && (res_y >= -0x7fff);

   if (!inside)
      return 0;

   switch (id)
   {
      case RETRO_DEVICE_ID_POINTER_X:
         return res_x;
      case RETRO_DEVICE_ID_POINTER_Y:
         return res_y;
      case RETRO_DEVICE_ID_POINTER_PRESSED:
         return pointer_down;
      default:
         return 0;
   }
}

static int16_t dinput_input_state(void *data,
      const struct retro_keybind **binds, unsigned port,
      unsigned device, unsigned index, unsigned id)
{
   struct dinput_input *di = (struct dinput_input*)data;
   int16_t ret;

   switch (device)
   {
      case RETRO_DEVICE_JOYPAD:
         return dinput_is_pressed(di, binds[port], port, id);

      case RETRO_DEVICE_KEYBOARD:
         return dinput_keyboard_pressed(di, id);

      case RETRO_DEVICE_ANALOG:
         ret = dinput_pressed_analog(di, binds[port], index, id);
         if (!ret)
            ret = input_joypad_analog(di->joypad, port,
                  index, id, g_settings.input.binds[port]);
         return ret;

      case RETRO_DEVICE_MOUSE:
         return dinput_mouse_state(di, id);

      case RETRO_DEVICE_POINTER:
      case RARCH_DEVICE_POINTER_SCREEN:
         return dinput_pointer_state(di, index, id,
               device == RARCH_DEVICE_POINTER_SCREEN);

      case RETRO_DEVICE_LIGHTGUN:
         return dinput_lightgun_state(di, id);

      default:
         return 0;
   }
}

/* these are defined in later SDKs, thus ifdeffed. */
#ifndef WM_POINTERUPDATE
#define WM_POINTERUPDATE                0x0245
#endif
#ifndef WM_POINTERDOWN
#define WM_POINTERDOWN                  0x0246
#endif
#ifndef WM_POINTERUP
#define WM_POINTERUP                    0x0247
#endif
#ifndef GET_POINTERID_WPARAM
#define GET_POINTERID_WPARAM(wParam)   (LOWORD(wParam))
#endif

/* Stores x/y in client coordinates. */
void dinput_pointer_store_pos(struct pointer_status *pointer, WPARAM lParam)
{
   POINT point;
   point.x = GET_X_LPARAM(lParam);
   point.y = GET_Y_LPARAM(lParam);
   ScreenToClient((HWND)driver.video_window, &point);
   pointer->pointer_x = point.x;
   pointer->pointer_y = point.y;
}

void dinput_add_pointer(struct dinput_input *di,
      struct pointer_status *new_pointer)
{
   new_pointer->next = NULL;
   struct pointer_status *insert_pos = &di->pointer_head;
   while (insert_pos->next)
      insert_pos = insert_pos->next;
   insert_pos->next = new_pointer;
}

void dinput_delete_pointer(struct dinput_input *di, int pointer_id)
{
   struct pointer_status *check_pos = &di->pointer_head;
   while (check_pos && check_pos->next)
   {
      if (check_pos->next->pointer_id == pointer_id)
      {
         struct pointer_status *to_delete = check_pos->next;
         check_pos->next = check_pos->next->next;
         free(to_delete);
      }
      check_pos = check_pos->next;
   }
}

struct pointer_status *dinput_find_pointer(struct dinput_input *di,
      int pointer_id)
{
   struct pointer_status *check_pos = di->pointer_head.next;
   while (check_pos)
   {
      if (check_pos->pointer_id == pointer_id)
         break;
      check_pos = check_pos->next;
   }
   return check_pos;
}

void dinput_clear_pointers(struct dinput_input *di)
{
   struct pointer_status *pointer = &di->pointer_head;
   while (pointer->next)
   {
      struct pointer_status *del = pointer->next;
      pointer->next = pointer->next->next;
      free(del);
   }
}

#ifdef __cplusplus
extern "C"
#endif
bool dinput_handle_message(void *dinput, UINT message, WPARAM wParam, LPARAM lParam)
{
   struct dinput_input *di = (struct dinput_input *)dinput;
   /* WM_POINTERDOWN   : Arrives for each new touch event 
    * with a new ID - add to list.
    * WM_POINTERUP     : Arrives once the pointer is no 
    * longer down - remove from list.
    * WM_POINTERUPDATE : arrives for both pressed and 
    * hovering pointers - ignore hovering
   */

   switch (message)
   {
      case WM_POINTERDOWN:
      {
         struct pointer_status *new_pointer = 
            (struct pointer_status *)malloc(sizeof(struct pointer_status));
         if (!new_pointer)
         {
            RARCH_ERR("dinput_handle_message: pointer allocation in WM_POINTERDOWN failed.\n");
            return false;
         }

         new_pointer->pointer_id = GET_POINTERID_WPARAM(wParam);
         dinput_pointer_store_pos(new_pointer, lParam);
         dinput_add_pointer(di, new_pointer);
         return true;
      }
      case WM_POINTERUP:
      {
         int pointer_id = GET_POINTERID_WPARAM(wParam);
         dinput_delete_pointer(di, pointer_id);
         return true;
      }
      case WM_POINTERUPDATE:
      {
         int pointer_id = GET_POINTERID_WPARAM(wParam);
         struct pointer_status *pointer = dinput_find_pointer(di, pointer_id);
         if (pointer)
            dinput_pointer_store_pos(pointer, lParam);
         return true;
      }
      case WM_DEVICECHANGE:
      {
         if (di->joypad)
            di->joypad->destroy();
         di->joypad = input_joypad_init_driver(g_settings.input.joypad_driver);
         break;
      }
   }
   return false;
}

static void dinput_free(void *data)
{
   struct dinput_input *di = (struct dinput_input*)data;
   LPDIRECTINPUT8 hold_ctx = g_ctx;

   if (di)
   {
      /* Prevent a joypad driver to kill our context prematurely. */
      g_ctx = NULL;
      if (di->joypad)
         di->joypad->destroy();
      g_ctx = hold_ctx;

      /* Clear any leftover pointers. */
      dinput_clear_pointers(di);

      if (di->keyboard)
         IDirectInputDevice8_Release(di->keyboard);

      if (di->mouse)
         IDirectInputDevice8_Release(di->mouse);

      free(di);
   }

   dinput_destroy_context();
}

static void dinput_grab_mouse(void *data, bool state)
{
   struct dinput_input *di = (struct dinput_input*)data;
   IDirectInputDevice8_Unacquire(di->mouse);
   IDirectInputDevice8_SetCooperativeLevel(di->mouse,
      (HWND)driver.video_window,
      state ?
      (DISCL_EXCLUSIVE | DISCL_FOREGROUND) :
      (DISCL_NONEXCLUSIVE | DISCL_FOREGROUND));
   IDirectInputDevice8_Acquire(di->mouse);
}

static bool dinput_set_rumble(void *data, unsigned port,
      enum retro_rumble_effect effect, uint16_t strength)
{
   struct dinput_input *di = (struct dinput_input*)data;
   return input_joypad_set_rumble(di->joypad, port, effect, strength);
}

static const rarch_joypad_driver_t *dinput_get_joypad_driver(void *data)
{
   struct dinput_input *di = (struct dinput_input*)data;
   return di->joypad;
}

static uint64_t dinput_get_capabilities(void *data)
{
   uint64_t caps = 0;

   caps |= (1 << RETRO_DEVICE_JOYPAD);
   caps |= (1 << RETRO_DEVICE_MOUSE);
   caps |= (1 << RETRO_DEVICE_KEYBOARD);
   caps |= (1 << RETRO_DEVICE_LIGHTGUN);
   caps |= (1 << RETRO_DEVICE_POINTER);
   caps |= (1 << RETRO_DEVICE_ANALOG);

   return caps;
}

input_driver_t input_dinput = {
   dinput_init,
   dinput_poll,
   dinput_input_state,
   dinput_key_pressed,
   dinput_free,
   NULL,
   NULL,
   dinput_get_capabilities,
   "dinput",

   dinput_grab_mouse,
   dinput_set_rumble,
   dinput_get_joypad_driver,
};

/* Keep track of which pad indexes are 360 controllers.
 * Not static, will be read in winxinput_joypad.c
 * -1 = not xbox pad, otherwise 0..3
 */

int g_xinput_pad_indexes[MAX_PLAYERS];
bool g_xinput_block_pads;

static void dinput_joypad_destroy(void)
{
   unsigned i;
   for (i = 0; i < MAX_PLAYERS; i++)
   {
      if (g_pads[i].joypad)
      {
         IDirectInputDevice8_Unacquire(g_pads[i].joypad);
         IDirectInputDevice8_Release(g_pads[i].joypad);
      }
      
      free(g_pads[i].joy_name);
      g_pads[i].joy_name = NULL;
      *g_settings.input.device_names[i] = '\0';
   }

   g_joypad_cnt = 0;
   memset(g_pads, 0, sizeof(g_pads));

   /* Can be blocked by global Dinput context. */
   dinput_destroy_context();
}

static BOOL CALLBACK enum_axes_cb(
      const DIDEVICEOBJECTINSTANCE *inst, void *p)
{
   LPDIRECTINPUTDEVICE8 joypad = (LPDIRECTINPUTDEVICE8)p;

   DIPROPRANGE range;
   memset(&range, 0, sizeof(range));
   range.diph.dwSize = sizeof(DIPROPRANGE);
   range.diph.dwHeaderSize = sizeof(DIPROPHEADER);
   range.diph.dwHow = DIPH_BYID;
   range.diph.dwObj = inst->dwType;
   range.lMin = -0x7fff;
   range.lMax = 0x7fff;
   IDirectInputDevice8_SetProperty(joypad, DIPROP_RANGE, &range.diph);

   return DIENUM_CONTINUE;
}

static const GUID common_xinput_guids[] = {
   {MAKELONG(0x28DE, 0x11FF),0x0000,0x0000,{0x00,0x00,0x50,0x49,0x44,0x56,0x49,0x44}}, // valve streaming pad
   {MAKELONG(0x045E, 0x02A1),0x0000,0x0000,{0x00,0x00,0x50,0x49,0x44,0x56,0x49,0x44}}, // wired 360 pad
   {MAKELONG(0x045E, 0x028E),0x0000,0x0000,{0x00,0x00,0x50,0x49,0x44,0x56,0x49,0x44}}  // wireless 360 pad
};

/* Based on SDL2's implementation. */
static bool guid_is_xinput_device(const GUID* product_guid)
{
   PRAWINPUTDEVICELIST raw_devs = NULL;
   unsigned num_raw_devs = 0;
   unsigned i;

   /* Check for well known XInput device GUIDs, 
    * thereby removing the need for the IG_ check.
    * This lets us skip RAWINPUT for popular devices. 
    *
    * Also, we need to do this for the Valve Streaming Gamepad 
    * because it's virtualized and doesn't show up in the device list.  */

   for (i = 0; i < ARRAY_SIZE(common_xinput_guids); ++i)
   {
      if (memcmp(product_guid, &common_xinput_guids[i], sizeof(GUID)) == 0)
         return true;
   }

   /* Go through RAWINPUT (WinXP and later) to find HID devices. */
   if (!raw_devs)
   {
      if ((GetRawInputDeviceList(NULL, &num_raw_devs,
                  sizeof(RAWINPUTDEVICELIST)) == (UINT)-1) || (!num_raw_devs))
         return false;

      raw_devs = (PRAWINPUTDEVICELIST)
         malloc(sizeof(RAWINPUTDEVICELIST) * num_raw_devs);
      if (!raw_devs)
         return false;

      if (GetRawInputDeviceList(raw_devs, &num_raw_devs,
               sizeof(RAWINPUTDEVICELIST)) == (UINT)-1)
      {
         free(raw_devs);
         raw_devs = NULL;
         return false;
      }
   }

   for (i = 0; i < num_raw_devs; i++)
   {
      RID_DEVICE_INFO rdi;
      char devName[128];
      UINT rdiSize = sizeof(rdi);
      UINT nameSize = sizeof(devName);

      rdi.cbSize = sizeof (rdi);
      if ((raw_devs[i].dwType == RIM_TYPEHID) &&
          (GetRawInputDeviceInfoA(raw_devs[i].hDevice, RIDI_DEVICEINFO, &rdi, &rdiSize) != ((UINT)-1)) &&
          (MAKELONG(rdi.hid.dwVendorId, rdi.hid.dwProductId) == ((LONG)product_guid->Data1)) &&
          (GetRawInputDeviceInfoA(raw_devs[i].hDevice, RIDI_DEVICENAME, devName, &nameSize) != ((UINT)-1)) &&
          (strstr(devName, "IG_") != NULL) )
      {
         free(raw_devs);
         raw_devs = NULL;
         return true;
      }
   }
   
   free(raw_devs);
   raw_devs = NULL;
   return false;
}

/* Forward declaration */
static const char *dinput_joypad_name(unsigned pad);

static unsigned g_last_xinput_pad_index;

static BOOL CALLBACK enum_joypad_cb(const DIDEVICEINSTANCE *inst, void *p)
{
   (void)p;
   if (g_joypad_cnt == MAX_PLAYERS)
      return DIENUM_STOP;

   LPDIRECTINPUTDEVICE8 *pad = &g_pads[g_joypad_cnt].joypad;

#ifdef __cplusplus
   if (FAILED(IDirectInput8_CreateDevice(
               g_ctx, inst->guidInstance, pad, NULL)))
#else
   if (FAILED(IDirectInput8_CreateDevice(
               g_ctx, &inst->guidInstance, pad, NULL)))
#endif
   return DIENUM_CONTINUE;
   
   g_pads[g_joypad_cnt].joy_name = strdup(inst->tszProductName);
   
#ifdef HAVE_WINXINPUT
#if 0
   bool is_xinput_pad = g_xinput_block_pads 
      && name_is_xinput_pad(inst->tszProductName);
#endif
   bool is_xinput_pad = g_xinput_block_pads 
      && guid_is_xinput_device(&inst->guidProduct);
   
   if (is_xinput_pad)
   {
      if (g_last_xinput_pad_index < 4)
         g_xinput_pad_indexes[g_joypad_cnt] = g_last_xinput_pad_index++;
      goto enum_iteration_done;
   }
#endif

   IDirectInputDevice8_SetDataFormat(*pad, &c_dfDIJoystick2);
   IDirectInputDevice8_SetCooperativeLevel(*pad, (HWND)driver.video_window,
         DISCL_NONEXCLUSIVE | DISCL_BACKGROUND);

   IDirectInputDevice8_EnumObjects(*pad, enum_axes_cb, 
         *pad, DIDFT_ABSAXIS);
         
#ifdef HAVE_WINXINPUT
   if (!is_xinput_pad)
#endif
   {
      strlcpy(g_settings.input.device_names[g_joypad_cnt],
            dinput_joypad_name(g_joypad_cnt),
            sizeof(g_settings.input.device_names[g_joypad_cnt]));
      /* TODO - implement VID/PID? */
      input_config_autoconfigure_joypad(g_joypad_cnt,
            dinput_joypad_name(g_joypad_cnt), 0, 0,
            dinput_joypad.ident);
   }

enum_iteration_done:
   g_joypad_cnt++;
   return DIENUM_CONTINUE; 
}

static bool dinput_joypad_init(void)
{
   unsigned i;
   if (!dinput_init_context())
      return false;
   
   g_last_xinput_pad_index = 0;
   
   for (i = 0; i < MAX_PLAYERS; ++i)
   {
      g_xinput_pad_indexes[i] = -1;
      g_pads[i].joy_name = NULL;
   }

   RARCH_LOG("Enumerating DInput joypads ...\n");
   IDirectInput8_EnumDevices(g_ctx, DI8DEVCLASS_GAMECTRL,
         enum_joypad_cb, NULL, DIEDFL_ATTACHEDONLY);
   RARCH_LOG("Done enumerating DInput joypads ...\n");
   return true;
}

static bool dinput_joypad_button(unsigned port_num, uint16_t joykey)
{
   if (joykey == NO_BTN)
      return false;

   const struct dinput_joypad *pad = &g_pads[port_num];
   if (!pad->joypad)
      return false;

   // Check hat.
   if (GET_HAT_DIR(joykey))
   {
      unsigned hat = GET_HAT(joykey);
      
      unsigned elems = sizeof(pad->joy_state.rgdwPOV) / 
         sizeof(pad->joy_state.rgdwPOV[0]);

      if (hat >= elems)
         return false;

      unsigned pov = pad->joy_state.rgdwPOV[hat];

      // Magic numbers I'm not sure where originate from.
      if (pov < 36000)
      {
         switch (GET_HAT_DIR(joykey))
         {
            case HAT_UP_MASK:
               return (pov >= 31500) || (pov <= 4500);
            case HAT_RIGHT_MASK:
               return (pov >= 4500) && (pov <= 13500);
            case HAT_DOWN_MASK:
               return (pov >= 13500) && (pov <= 22500);
            case HAT_LEFT_MASK:
               return (pov >= 22500) && (pov <= 31500);
         }
      }

      return false;
   }
   else
   {
      unsigned elems = sizeof(pad->joy_state.rgbButtons) / 
         sizeof(pad->joy_state.rgbButtons[0]);

      if (joykey < elems)
         return pad->joy_state.rgbButtons[joykey];
   }

   return false;
}

static int16_t dinput_joypad_axis(unsigned port_num, uint32_t joyaxis)
{
   if (joyaxis == AXIS_NONE)
      return 0;

   const struct dinput_joypad *pad = &g_pads[port_num];
   if (!pad->joypad)
      return 0;

   int val = 0;

   int axis    = -1;
   bool is_neg = false;
   bool is_pos = false;

   if (AXIS_NEG_GET(joyaxis) <= 5)
   {
      axis = AXIS_NEG_GET(joyaxis);
      is_neg = true;
   }
   else if (AXIS_POS_GET(joyaxis) <= 5)
   {
      axis = AXIS_POS_GET(joyaxis);
      is_pos = true;
   }

   switch (axis)
   {
      case 0:
         val = pad->joy_state.lX;
         break;
      case 1:
         val = pad->joy_state.lY;
         break;
      case 2:
         val = pad->joy_state.lZ;
         break;
      case 3:
         val = pad->joy_state.lRx;
         break;
      case 4:
         val = pad->joy_state.lRy;
         break;
      case 5:
         val = pad->joy_state.lRz;
         break;
   }

   if (is_neg && val > 0)
      val = 0;
   else if (is_pos && val < 0)
      val = 0;

   return val;
}

static void dinput_joypad_poll(void)
{
   unsigned i;
   for (i = 0; i < MAX_PLAYERS; i++)
   {
      struct dinput_joypad *pad = &g_pads[i];

      if (pad->joypad && g_xinput_pad_indexes[i] < 0)
      {
         memset(&pad->joy_state, 0, sizeof(pad->joy_state));

         if (FAILED(IDirectInputDevice8_Poll(pad->joypad)))
         {
            if (FAILED(IDirectInputDevice8_Acquire(pad->joypad)))
            {
               memset(&pad->joy_state, 0, sizeof(DIJOYSTATE2));
               continue;
            }

            /* If this fails, something *really* bad must have happened. */
            if (FAILED(IDirectInputDevice8_Poll(pad->joypad)))
            {
               memset(&pad->joy_state, 0, sizeof(DIJOYSTATE2));
               continue;
            }
         }

         IDirectInputDevice8_GetDeviceState(pad->joypad,
               sizeof(DIJOYSTATE2), &pad->joy_state);
      }
   }
}

static bool dinput_joypad_query_pad(unsigned pad)
{
   return pad < MAX_PLAYERS && g_pads[pad].joypad;
}

static const char *dinput_joypad_name(unsigned pad)
{
   if (pad < MAX_PLAYERS)
      return g_pads[pad].joy_name;

   return NULL;
}

rarch_joypad_driver_t dinput_joypad = {
   dinput_joypad_init,
   dinput_joypad_query_pad,
   dinput_joypad_destroy,
   dinput_joypad_button,
   dinput_joypad_axis,
   dinput_joypad_poll,
   NULL,
   dinput_joypad_name,
   "dinput",
};