Lag using Xlib/X11 event handling in C - c

Question

Beginner user of C here.
I'm trying to build a library in C using X11/Xlib so I can use it just for little projects and I'm running into a problem when trying to handle events to get input(button presses and key presses) from the user. It works fine for a while and then it starts to build up a significant lag over time.
Right now what I have is my program checking if there is an event waiting and if there is, retrieving it.
I think that my problem right now is that the events are getting stored in memory and its bogging down the program. But that's just a total guess.
Any help will be appreciated. Thank you.
EDIT: Forgot code (I knew I forgot something)
The two functions in question are:
int event_waiting()
{
XEvent event;
if(XCheckMaskEvent(dspy,-1,&event)) {
if(event.type==KeyPress) {
XPutBackEvent(dspy,&event);
return 1;
} else if (event.type==ButtonPress) {
XPutBackEvent(dspy,&event);
return 1;
}
} /* <<=== added missing close-curly here */
return 0;
}
char wait()
{
XEvent event;
XNextEvent(dspy,&event);
if(event.type==KeyPress) {
saved_x = event.xkey.x;
saved_y = event.xkey.y;
return XLookupKeysym(&event.xkey,0);
} else if(event.type==ButtonPress) {
saved_x = event.xkey.x;
saved_y = event.xkey.y;
return event.xbutton.button;
}
}
And then they are called in the main like so,
if (event_waiting()){
char c = wait();
//Switch case goes here
}
EDIT 2: UPDATED CODE
XEvent event;
if(XCheckMaskEvent(display,-1,&event))
{
if(event.type==KeyPress) {
XPutBackEvent(display,&event);
return 1;
} else if (event.type==ButtonPress) {
XPutBackEvent(display,&event);
return 1;
}
}
XFlush(display);
return 0;
`

Answer 1

The lag, which gets worse over time, means that you have many untouched events in your event queue, which slows down XCheckMaskEvent().
Try specifying events using XSelectInput(... ButtonPressMask | KeyPressMask), and try flushing the event queue using XFlush() if there is no event in which you are interested:
if(event.type==KeyPress) {
XPutBackEvent(dspy,&event);
return 1;
} else if (event.type==ButtonPress) {
XPutBackEvent(dspy,&event);
return 1;
} else {
XFlush(dspy); // this
}