From 5287559aeebbe34e86afad7b80b8f79d036ec1a8 Mon Sep 17 00:00:00 2001
From: krcroft <krcroft@users.noreply.github.com>
Date: Sun, 19 Apr 2020 11:49:15 -0700
Subject: [PATCH] Don't initialize and manage joysticks in SDLmain

Two notable changes:

1. Eliminates the joystick setup from SDLmain, allowing
the mapper's QueryJoysticks() function to be the sole
setup and configuration point for both the SDL Joystick
subsystem and DOSBox's internal configuration of the
joysticks.

2. SDLmain's event loop previously perform some joystick-
specific timing and always called the Mapper's UpdateJoysticks
function; neither of which are needed if the user has disabled
joystick support or if joysticks aren't physically present.
This update now make this entire process conditional on both
of the latter (which is set by the Mapper's QueryJoysticks).
---
 include/mapper.h       |  3 ++-
 src/gui/sdl_mapper.cpp | 11 ++++++++---
 src/gui/sdlmain.cpp    | 26 +++++++++-----------------
 3 files changed, 19 insertions(+), 21 deletions(-)

diff --git a/include/mapper.h b/include/mapper.h
index 674a9363..975d865d 100644
--- a/include/mapper.h
+++ b/include/mapper.h
@@ -36,7 +36,8 @@ void MAPPER_BindKeys();
 void MAPPER_StartUp(Section * sec);
 void MAPPER_Run(bool pressed);
 void MAPPER_DisplayUI();
-void MAPPER_LosingFocus(void);
+void MAPPER_LosingFocus();
+bool MAPPER_IsUsingJoysticks();
 std::vector<std::string> MAPPER_GetEventNames(const std::string &prefix);
 void MAPPER_AutoType(std::vector<std::string> &sequence,
                      const uint32_t wait_ms,
diff --git a/src/gui/sdl_mapper.cpp b/src/gui/sdl_mapper.cpp
index 0d549c8d..e884de5a 100644
--- a/src/gui/sdl_mapper.cpp
+++ b/src/gui/sdl_mapper.cpp
@@ -2500,9 +2500,10 @@ void BIND_MappingEvents() {
 /**
  *  Queries SDL's joysticks and sets joytype accordingly.
  *  If no joysticks are valid then joytype is left at JOY_NONE.
- *  Also resets mapper.sticks.num_groups to 0 and
- *  mapper.sticks.num to the number of found SDL joysticks.
- */
+ *  Also resets mapper.sticks.num_groups to 0, mapper.sticks.num
+ *  to the number of found SDL joysticks, and enables the boolean
+ *  joysticks_active if joystick support is enabled and are present.
+ */ 
 static void QueryJoysticks() {
 	// Initialize SDL's Joystick and Event subsystems, if needed
 	if (SDL_WasInit(SDL_INIT_JOYSTICK) != SDL_INIT_JOYSTICK)
@@ -2597,6 +2598,10 @@ static void CreateBindGroups() {
 	}
 }
 
+bool MAPPER_IsUsingJoysticks() {
+	return (mapper.sticks.num > 0);
+}
+
 #if defined (REDUCE_JOYSTICK_POLLING)
 void MAPPER_UpdateJoysticks() {
 	for (Bitu i=0; i<mapper.sticks.num_groups; i++) {
diff --git a/src/gui/sdlmain.cpp b/src/gui/sdlmain.cpp
index fb020d6a..1fe9def5 100644
--- a/src/gui/sdlmain.cpp
+++ b/src/gui/sdlmain.cpp
@@ -47,6 +47,7 @@
 #include "cross.h"
 #include "video.h"
 #include "mouse.h"
+#include "joystick.h"
 #include "pic.h"
 #include "timer.h"
 #include "setup.h"
@@ -62,7 +63,6 @@
 #include "../libs/ppscale/ppscale.h"
 
 #define MAPPERFILE "mapper-sdl2-" VERSION ".map"
-//#define DISABLE_JOYSTICK
 
 #if C_OPENGL
 //Define to disable the usage of the pixel buffer object
@@ -344,7 +344,6 @@ struct SDL_Block {
 	int  ppscale_x, ppscale_y; /* x and y scales for pixel-perfect     */
 	bool double_h, double_w;   /* double-height and double-width flags */
 	SDL_Rect updateRects[1024];
-	Bitu num_joysticks;
 #if defined (WIN32)
 	// Time when sdl regains focus (alt-tab) in windowed mode
 	Bit32u focus_ticks;
@@ -2457,12 +2456,14 @@ void GFX_Events() {
 
 	SDL_Event event;
 #if defined (REDUCE_JOYSTICK_POLLING)
-	static int poll_delay = 0;
-	int time = GetTicks();
-	if (time - poll_delay > 20) {
-		poll_delay = time;
-		if (sdl.num_joysticks > 0) SDL_JoystickUpdate();
-		MAPPER_UpdateJoysticks();
+	if (MAPPER_IsUsingJoysticks()) {
+		static int poll_delay = 0;
+		int time = GetTicks();
+		if (time - poll_delay > 20) {
+			poll_delay = time;
+			SDL_JoystickUpdate();
+			MAPPER_UpdateJoysticks();
+		}
 	}
 #endif
 	while (SDL_PollEvent(&event)) {
@@ -3151,18 +3152,9 @@ int main(int argc, char* argv[]) {
 	// Once initialized, ensure we clean up SDL for all exit conditions
 	atexit(SDL_Quit);
 
-#ifndef DISABLE_JOYSTICK
-	//Initialise Joystick separately. This way we can warn when it fails instead
-	//of exiting the application
-	if( SDL_InitSubSystem(SDL_INIT_JOYSTICK) < 0 )
-		LOG_MSG("Failed to init joystick support");
-#endif
-
 	sdl.laltstate = SDL_KEYUP;
 	sdl.raltstate = SDL_KEYUP;
 
-	sdl.num_joysticks=SDL_NumJoysticks();
-
 	CROSS_DetermineConfigPaths();
 
 	/* Parse configuration files */