input_common: Eliminate most global state

Abstracts most of the input mechanisms under an InputSubsystem class
that is managed by the frontends, eliminating any static constructors
and destructors. This gets rid of global accessor functions and also
allows the frontends to have a more fine-grained control over the
lifecycle of the input subsystem.

This also makes it explicit which interfaces rely on the input subsystem
instead of making it opaque in the interface functions. All that remains
to migrate over is the factories, which can be done in a separate
change.

6 files changed, 37 insertions, 15 deletions

diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2.cpp b/src/yuzu_cmd/emu_window/emu_window_sdl2.cpp
index e5e684206..a804d5185 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2.cpp
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2.cpp
@@ -13,23 +13,25 @@
 #include "input_common/sdl/sdl.h"
 #include "yuzu_cmd/emu_window/emu_window_sdl2.h"
 
-EmuWindow_SDL2::EmuWindow_SDL2(Core::System& system, bool fullscreen) : system{system} {
+EmuWindow_SDL2::EmuWindow_SDL2(Core::System& system, bool fullscreen,
+                               InputCommon::InputSubsystem* input_subsystem_)
+    : system{system}, input_subsystem{input_subsystem_} {
     if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_JOYSTICK) < 0) {
         LOG_CRITICAL(Frontend, "Failed to initialize SDL2! Exiting...");
         exit(1);
     }
-    InputCommon::Init();
+    input_subsystem->Initialize();
     SDL_SetMainReady();
 }
 
 EmuWindow_SDL2::~EmuWindow_SDL2() {
-    InputCommon::Shutdown();
+    input_subsystem->Shutdown();
     SDL_Quit();
 }
 
 void EmuWindow_SDL2::OnMouseMotion(s32 x, s32 y) {
     TouchMoved((unsigned)std::max(x, 0), (unsigned)std::max(y, 0));
-    InputCommon::GetMotionEmu()->Tilt(x, y);
+    input_subsystem->GetMotionEmu()->Tilt(x, y);
 }
 
 void EmuWindow_SDL2::OnMouseButton(u32 button, u8 state, s32 x, s32 y) {
@@ -41,9 +43,9 @@ void EmuWindow_SDL2::OnMouseButton(u32 button, u8 state, s32 x, s32 y) {
         }
     } else if (button == SDL_BUTTON_RIGHT) {
         if (state == SDL_PRESSED) {
-            InputCommon::GetMotionEmu()->BeginTilt(x, y);
+            input_subsystem->GetMotionEmu()->BeginTilt(x, y);
         } else {
-            InputCommon::GetMotionEmu()->EndTilt();
+            input_subsystem->GetMotionEmu()->EndTilt();
         }
     }
 }
@@ -79,9 +81,9 @@ void EmuWindow_SDL2::OnFingerUp() {
 
 void EmuWindow_SDL2::OnKeyEvent(int key, u8 state) {
     if (state == SDL_PRESSED) {
-        InputCommon::GetKeyboard()->PressKey(key);
+        input_subsystem->GetKeyboard()->PressKey(key);
     } else if (state == SDL_RELEASED) {
-        InputCommon::GetKeyboard()->ReleaseKey(key);
+        input_subsystem->GetKeyboard()->ReleaseKey(key);
     }
 }
 
diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2.h b/src/yuzu_cmd/emu_window/emu_window_sdl2.h
index fffac4252..82750ffec 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2.h
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2.h
@@ -14,9 +14,14 @@ namespace Core {
 class System;
 }
 
+namespace InputCommon {
+class InputSubsystem;
+}
+
 class EmuWindow_SDL2 : public Core::Frontend::EmuWindow {
 public:
-    explicit EmuWindow_SDL2(Core::System& system, bool fullscreen);
+    explicit EmuWindow_SDL2(Core::System& system, bool fullscreen,
+                            InputCommon::InputSubsystem* input_subsystem);
     ~EmuWindow_SDL2();
 
     /// Polls window events
@@ -76,4 +81,7 @@ protected:
 
     /// Keeps track of how often to update the title bar during gameplay
     u32 last_time = 0;
+
+    /// Input subsystem to use with this window.
+    InputCommon::InputSubsystem* input_subsystem;
 };
diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.cpp b/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.cpp
index e78025737..881b67a76 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.cpp
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.cpp
@@ -87,8 +87,9 @@ bool EmuWindow_SDL2_GL::SupportsRequiredGLExtensions() {
     return unsupported_ext.empty();
 }
 
-EmuWindow_SDL2_GL::EmuWindow_SDL2_GL(Core::System& system, bool fullscreen)
-    : EmuWindow_SDL2{system, fullscreen} {
+EmuWindow_SDL2_GL::EmuWindow_SDL2_GL(Core::System& system, bool fullscreen,
+                                     InputCommon::InputSubsystem* input_subsystem)
+    : EmuWindow_SDL2{system, fullscreen, input_subsystem} {
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_COMPATIBILITY);
diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.h b/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.h
index 48bb41683..732a64edd 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.h
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2_gl.h
@@ -8,9 +8,14 @@
 #include "core/frontend/emu_window.h"
 #include "yuzu_cmd/emu_window/emu_window_sdl2.h"
 
+namespace InputCommon {
+class InputSubsystem;
+}
+
 class EmuWindow_SDL2_GL final : public EmuWindow_SDL2 {
 public:
-    explicit EmuWindow_SDL2_GL(Core::System& system, bool fullscreen);
+    explicit EmuWindow_SDL2_GL(Core::System& system, bool fullscreen,
+                               InputCommon::InputSubsystem* input_subsystem);
     ~EmuWindow_SDL2_GL();
 
     void Present() override;
diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.cpp b/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.cpp
index cb8e68a39..53491f86e 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.cpp
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.cpp
@@ -19,8 +19,9 @@
 #include <SDL.h>
 #include <SDL_syswm.h>
 
-EmuWindow_SDL2_VK::EmuWindow_SDL2_VK(Core::System& system, bool fullscreen)
-    : EmuWindow_SDL2{system, fullscreen} {
+EmuWindow_SDL2_VK::EmuWindow_SDL2_VK(Core::System& system, bool fullscreen,
+                                     InputCommon::InputSubsystem* input_subsystem)
+    : EmuWindow_SDL2{system, fullscreen, input_subsystem} {
     const std::string window_title = fmt::format("yuzu {} | {}-{} (Vulkan)", Common::g_build_name,
                                                  Common::g_scm_branch, Common::g_scm_desc);
     render_window =
diff --git a/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.h b/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.h
index 77a6ca72b..f99704d4c 100644
--- a/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.h
+++ b/src/yuzu_cmd/emu_window/emu_window_sdl2_vk.h
@@ -13,9 +13,14 @@ namespace Core {
 class System;
 }
 
+namespace InputCommon {
+class InputSubsystem;
+}
+
 class EmuWindow_SDL2_VK final : public EmuWindow_SDL2 {
 public:
-    explicit EmuWindow_SDL2_VK(Core::System& system, bool fullscreen);
+    explicit EmuWindow_SDL2_VK(Core::System& system, bool fullscreen,
+                               InputCommon::InputSubsystem* input_subsystem);
     ~EmuWindow_SDL2_VK();
 
     void Present() override;