[HID] Allow winkey driver to use the first unused user index

This removes the user_index == 0 requirement from the InputSystem code, and updates WinKeyInputDriver to use the first non-connected user index if it can.

Eg. if you had 2 XInput controllers plugged in, those two will take up user index 0 and 1, and keyboard will take user index 2.
If all four indexes are taken up already, the WinKey driver will be disabled.

(This is done by passing already-setup drivers to each drivers Setup function: since WinKey is the last to be setup, this'll let it query the XInput driver and find which user_index it should handle)

src/xenia/app/xenia_main.cc

@@ -195,7 +195,7 @@ std::vector<std::unique_ptr<hid::InputDriver>> CreateInputDrivers(
 #endif  // XE_PLATFORM_WIN32
     factory.Add("sdl", xe::hid::sdl::Create);
     for (auto& driver : factory.CreateAll(cvars::hid, window)) {
-      if (XSUCCEEDED(driver->Setup())) {
+      if (XSUCCEEDED(driver->Setup(drivers))) {
         drivers.emplace_back(std::move(driver));
       }
     }

src/xenia/hid/input_driver.h

@@ -10,6 +10,9 @@
 #ifndef XENIA_HID_INPUT_DRIVER_H_
 #define XENIA_HID_INPUT_DRIVER_H_
 
+#include <memory>
+#include <vector>
+
 #include "xenia/hid/input.h"
 #include "xenia/xbox.h"
 
@@ -28,7 +31,8 @@ class InputDriver {
  public:
   virtual ~InputDriver();
 
-  virtual X_STATUS Setup() = 0;
+  virtual X_STATUS Setup(
+      std::vector<std::unique_ptr<hid::InputDriver>>& drivers) = 0;
 
   virtual X_RESULT GetCapabilities(uint32_t user_index, uint32_t flags,
                                    X_INPUT_CAPABILITIES* out_caps) = 0;

src/xenia/hid/nop/nop_input_driver.cc

@@ -19,7 +19,10 @@ NopInputDriver::NopInputDriver(xe::ui::Window* window) : InputDriver(window) {}
 
 NopInputDriver::~NopInputDriver() = default;
 
-X_STATUS NopInputDriver::Setup() { return X_STATUS_SUCCESS; }
+X_STATUS NopInputDriver::Setup(
+    std::vector<std::unique_ptr<InputDriver>>& drivers) {
+  return X_STATUS_SUCCESS;
+}
 
 // TODO(benvanik): spoof a device so that games don't stop waiting for
 //     a controller to be plugged in.

src/xenia/hid/nop/nop_input_driver.h

@@ -21,7 +21,8 @@ class NopInputDriver : public InputDriver {
   explicit NopInputDriver(xe::ui::Window* window);
   ~NopInputDriver() override;
 
-  X_STATUS Setup() override;
+  X_STATUS Setup(
+      std::vector<std::unique_ptr<hid::InputDriver>>& drivers) override;
 
   X_RESULT GetCapabilities(uint32_t user_index, uint32_t flags,
                            X_INPUT_CAPABILITIES* out_caps) override;

src/xenia/hid/winkey/winkey_input_driver.cc

@@ -45,11 +45,40 @@ WinKeyInputDriver::WinKeyInputDriver(xe::ui::Window* window)
 
 WinKeyInputDriver::~WinKeyInputDriver() = default;
 
-X_STATUS WinKeyInputDriver::Setup() { return X_STATUS_SUCCESS; }
+X_STATUS WinKeyInputDriver::Setup(
+    std::vector<std::unique_ptr<hid::InputDriver>>& drivers) {
+  int index = 0;
+  X_INPUT_STATE state;
+
+  // Search already added drivers for an index that none of them can use
+  while (index < 4) {
+    bool not_connected = false;
+
+    for (auto& driver : drivers) {
+      if (driver.get()->GetState(index, &state) !=
+          X_ERROR_DEVICE_NOT_CONNECTED) {
+        not_connected = false;
+        break;
+      }
+      not_connected = true;
+    }
+
+    if (not_connected) {
+      user_index_ = index;
+      return X_STATUS_SUCCESS;
+    }
+    index++;
+  }
+
+  // All indexes are in use...
+  user_index_ = -1;
+  // Return error so this driver won't get used
+  return X_ERROR_DEVICE_NOT_CONNECTED;
+}
 
 X_RESULT WinKeyInputDriver::GetCapabilities(uint32_t user_index, uint32_t flags,
                                             X_INPUT_CAPABILITIES* out_caps) {
-  if (user_index != 0) {
+  if (user_index != user_index_) {
     return X_ERROR_DEVICE_NOT_CONNECTED;
   }
 
@@ -74,7 +103,7 @@ X_RESULT WinKeyInputDriver::GetCapabilities(uint32_t user_index, uint32_t flags,
 
 X_RESULT WinKeyInputDriver::GetState(uint32_t user_index,
                                      X_INPUT_STATE* out_state) {
-  if (user_index != 0) {
+  if (user_index != user_index_) {
     return X_ERROR_DEVICE_NOT_CONNECTED;
   }
 
@@ -214,7 +243,7 @@ X_RESULT WinKeyInputDriver::GetState(uint32_t user_index,
 
 X_RESULT WinKeyInputDriver::SetState(uint32_t user_index,
                                      X_INPUT_VIBRATION* vibration) {
-  if (user_index != 0) {
+  if (user_index != user_index_) {
     return X_ERROR_DEVICE_NOT_CONNECTED;
   }
 
@@ -223,7 +252,7 @@ X_RESULT WinKeyInputDriver::SetState(uint32_t user_index,
 
 X_RESULT WinKeyInputDriver::GetKeystroke(uint32_t user_index, uint32_t flags,
                                          X_INPUT_KEYSTROKE* out_keystroke) {
-  if (user_index != 0) {
+  if (user_index != user_index_) {
     return X_ERROR_DEVICE_NOT_CONNECTED;
   }
 
@@ -356,7 +385,7 @@ X_RESULT WinKeyInputDriver::GetKeystroke(uint32_t user_index, uint32_t flags,
   out_keystroke->virtual_key = virtual_key;
   out_keystroke->unicode = unicode;
   out_keystroke->flags = keystroke_flags;
-  out_keystroke->user_index = 0;
+  out_keystroke->user_index = user_index_;
   out_keystroke->hid_code = hid_code;
 
   // X_ERROR_EMPTY if no new keys

src/xenia/hid/winkey/winkey_input_driver.h

@@ -24,7 +24,8 @@ class WinKeyInputDriver : public InputDriver {
   explicit WinKeyInputDriver(xe::ui::Window* window);
   ~WinKeyInputDriver() override;
 
-  X_STATUS Setup() override;
+  X_STATUS Setup(
+      std::vector<std::unique_ptr<hid::InputDriver>>& drivers) override;
 
   X_RESULT GetCapabilities(uint32_t user_index, uint32_t flags,
                            X_INPUT_CAPABILITIES* out_caps) override;
@@ -33,6 +34,8 @@ class WinKeyInputDriver : public InputDriver {
   X_RESULT GetKeystroke(uint32_t user_index, uint32_t flags,
                         X_INPUT_KEYSTROKE* out_keystroke) override;
 
+  void user_index(uint32_t index) { user_index_ = index; }
+
  protected:
   struct KeyEvent {
     int vkey = 0;
@@ -45,6 +48,8 @@ class WinKeyInputDriver : public InputDriver {
   std::queue<KeyEvent> key_events_;
 
   uint32_t packet_number_;
+
+  uint32_t user_index_ = 1;
 };
 
 }  // namespace winkey

src/xenia/hid/xinput/xinput_input_driver.cc

@@ -42,7 +42,8 @@ XInputInputDriver::~XInputInputDriver() {
   }
 }
 
-X_STATUS XInputInputDriver::Setup() {
+X_STATUS XInputInputDriver::Setup(
+    std::vector<std::unique_ptr<InputDriver>>& drivers) {
   HMODULE module = LoadLibraryW(L"xinput1_4.dll");
   if (!module) {
     module = LoadLibraryW(L"xinput1_3.dll");

src/xenia/hid/xinput/xinput_input_driver.h

@@ -21,7 +21,8 @@ class XInputInputDriver : public InputDriver {
   explicit XInputInputDriver(xe::ui::Window* window);
   ~XInputInputDriver() override;
 
-  X_STATUS Setup() override;
+  X_STATUS Setup(
+      std::vector<std::unique_ptr<hid::InputDriver>>& drivers) override;
 
   X_RESULT GetCapabilities(uint32_t user_index, uint32_t flags,
                            X_INPUT_CAPABILITIES* out_caps) override;

src/xenia/kernel/xam/xam_input.cc

@@ -101,7 +101,7 @@ dword_result_t XamInputGetState(dword_t user_index, dword_t flags,
   }
 
   auto input_system = kernel_state()->emulator()->input_system();
-  return input_system->GetState(user_index, input_state);
+  return input_system->GetState(actual_user_index, input_state);
 }
 DECLARE_XAM_EXPORT1(XamInputGetState, kInput, kImplemented);
 
@@ -119,7 +119,7 @@ dword_result_t XamInputSetState(dword_t user_index, dword_t unk,
   }
 
   auto input_system = kernel_state()->emulator()->input_system();
-  return input_system->SetState(user_index, vibration);
+  return input_system->SetState(actual_user_index, vibration);
 }
 DECLARE_XAM_EXPORT1(XamInputSetState, kInput, kImplemented);
 
@@ -182,12 +182,17 @@ X_HRESULT_result_t XamUserGetDeviceContext(dword_t user_index, dword_t unk,
   // Games check the result - usually with some masking.
   // If this function fails they assume zero, so let's fail AND
   // set zero just to be safe.
-  *out_ptr = 0;
-  if (!user_index || (user_index & 0xFF) == 0xFF) {
-    return X_E_SUCCESS;
-  } else {
-    return X_E_DEVICE_NOT_CONNECTED;
+  // *out_ptr = 0;
+
+  uint32_t actual_user_index = user_index;
+  if ((user_index & 0xFF) == 0xFF) {
+    // Always pin user to 0.
+    actual_user_index = 0;
   }
+
+  auto input_system = kernel_state()->emulator()->input_system();
+  X_INPUT_STATE state;
+  return input_system->GetState(actual_user_index, &state);
 }
 DECLARE_XAM_EXPORT1(XamUserGetDeviceContext, kInput, kStub);