controls kbd+mouse with a controller

controller_daemon.c

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <linux/input.h>
#include <fcntl.h>
#include <stdlib.h>
#include <X11/X.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/extensions/XTest.h>
#include <stdbool.h>
#include <pthread.h>

int fd;
struct input_event e;
//set up my storage
struct joystick_storage {
	//left stick X and Y
	int lSX;
	int lSY;
	//right stick X and Y
	int rSX;
	int rSY;
	//buttons A, B, X, Y
	int a;
	int aChanged;
	int b;
	int bChanged;
	int x;
	int xChanged;
	int y;
	int yChanged;
};
struct joystick_storage controller;

void getMousePos(Display* dpy, Window root, int* xOut, int* yOut) {
	int winXOut, winYOut;
	unsigned int maskOut;
	Window rootOut, childOut;
	XQueryPointer(dpy, root, &rootOut, &childOut, xOut, yOut, &winXOut, &winYOut, &maskOut);
}
void moveMouseAbs(Display* dpy, Window root, int x, int y) {
	XWarpPointer(dpy, None, root, 0, 0, 0, 0, x, y);
}
void moveMouseRel(Display* dpy, Window root, int dx, int dy) {
	int x;
	int y;
	getMousePos(dpy, root, &x, &y);
	moveMouseAbs(dpy, root, x + dx, y + dy);
}
int populateEvent(struct input_event *ev, int fD) {
	memset(ev, 0, sizeof(*ev));
	return read(fD, ev, sizeof(*ev));
}
void *updateEvent() {
	for (;;) {
		populateEvent(&e, fd);
		switch (e.type) {
			case EV_ABS:
			switch (e.code) {
				case ABS_X:
				controller.lSX = e.value;
				break;
				case ABS_Y:
				controller.lSY = e.value;
				break;
				case ABS_RX:
				controller.rSX = e.value;
				break;
				case ABS_RY:
				controller.rSY = e.value;
				break;
			}
			break;

			case EV_KEY:
			switch (e.code) {
				case BTN_A:
				if (e.value != controller.a)
					controller.aChanged = 1;
				controller.a = e.value;
				if (controller.a > 1)
					controller.a = 1;
				break;
				case BTN_B:
				if (e.value != controller.b)
					controller.bChanged = 1;
				controller.b = e.value;
				if (controller.b > 1)
					controller.b = 1;
				break;
				case BTN_X:
				if (e.value != controller.x)
					controller.xChanged = 1;
				controller.x = e.value;
				if (controller.x > 1)
					controller.x = 1;
				break;
				case BTN_Y:
				if (e.value != controller.y)
					controller.yChanged = 1;
				controller.y = e.value;
				if (controller.y > 1)
					controller.y = 1;
				break;
			}
		}
	}
}
int main() {
	//set up udev boilerplate (output from controller)

	fd = open("/dev/input/event16", O_RDONLY | O_NONBLOCK);
	//set up x11 boilerplate (input to computer)
	Display *dpy;
	Window root;
	dpy = XOpenDisplay(0);
	root = XRootWindow(dpy, 0);
	XSelectInput(dpy, root, KeyReleaseMask);
	memset(&controller, 0, sizeof(controller));
	//threading boilerplate
	pthread_t controllerUpdate;
	pthread_create(&controllerUpdate, NULL, updateEvent, NULL);
	//main loop
	for (;;) {
		//move the mouse
		moveMouseRel(dpy, root,
			(int)((long double)controller.lSX / 5000.0), (int)((long double)controller.lSY / 5000.0));
		//press mouse buttons
		if (controller.aChanged) {
			switch (controller.a){
				case 1:
				XTestFakeButtonEvent(dpy, 1, true, 0);
				break;
				case 0:
				XTestFakeButtonEvent(dpy, 1, false, 0);
				break;
			}
			controller.aChanged = 0;
		}
		if (controller.bChanged) {
			switch (controller.b){
				case 1:
				XTestFakeButtonEvent(dpy, 3, true, 0);
				break;
				case 0:
				XTestFakeButtonEvent(dpy, 3, false, 0);
				break;
			}
			controller.bChanged = 0;
		}
		if (controller.yChanged) {
			switch (controller.y){
				case 1:
				XTestFakeButtonEvent(dpy, 2, true, 0);
				break;
				case 0:
				XTestFakeButtonEvent(dpy, 2, false, 0);
				break;
			}
			controller.yChanged = 0;
		}
		XFlush(dpy);
		usleep(10000);
	}
	//end
	close(fd);
	exit(0);
	return 0;
}

Makefile

all:
	gcc -lX11 -lpthread -lXtst -std=gnu11 main.c