Added uiEventFree(). Now to add it to the tests and see what AddressSanitizer says afterward.

common/events.c

@@ -24,6 +24,7 @@ static int handlerCmp(const void *a, const void *b)
 
 struct uiEvent {
 	uiEventOptions opts;
+	bool internal;
 	uiprivArray handlers;
 	uiprivArray unusedIDs;
 	bool firing;
@@ -59,6 +60,26 @@ uiEvent *uiNewEvent(const uiEventOptions *options)
 	return ret; \
 }
 
+void uiFreeEvent(uiEvent *e)
+{
+	if (!uiprivCheckInitializedAndThread())
+		return;
+	checkEventNonnull(e, /* nothing */);
+	if (e->internal) {
+		uiprivProgrammerErrorFreeingInternalEvent();
+		return;
+	}
+	checkEventNotFiring(e, /* nothing */);
+	if (e->handlers.len != 0) {
+		uiprivProgrammerErrorFreeingEventInUse();
+		return;
+	}
+
+	uiprivArrayFree(e->unusedIDs);
+	uiprivArrayFree(e->handlers);
+	uiprivFree(e);
+}
+
 static bool checkEventSender(const uiEvent *e, void *sender, const char *func)
 {
 	if (e->opts.Global && sender != NULL) {

common/programmererrors.h

@@ -36,3 +36,9 @@
 
 #define uiprivProgrammerErrorRecursiveEventFire() \
 	uiprivProgrammerError("attempt to fire a uiEvent while it is already being fired")
+
+#define uiprivProgrammerErrorFreeingInternalEvent() \
+	uiprivProgrammerError("attempt to free a libui-provided uiEvent")
+
+#define uiprivProgrammerErrorFreeingEventInUse() \
+	uiprivProgrammerError("attempt to free a uiEvent that still has handlers registered")

doc/events.md

@@ -50,6 +50,16 @@ uiEvent *uiNewEvent(const uiEventOptions *options);
 
 It is a programmer error to specify `NULL` for `options`.
 
+### `uiFreeEvent()`
+
+```c
+uiprivExtern void uiFreeEvent(uiEvent *e);
+```
+
+Frees the given event. The event must not be a libui-provided event, and must not have any handlers registered to it.
+
+It is a programmer error to pass `NULL` for the given event, or to pass in an event that is currently firing.
+
 ### `uiEventAddHandler()`
 
 ```c

ui.h

@@ -54,7 +54,7 @@ struct uiEventOptions {
 };
 
 uiprivExtern uiEvent *uiNewEvent(const uiEventOptions *options);
-// TODO uiFreeEvent()
+uiprivExtern void uiFreeEvent(uiEvent *e);
 uiprivExtern int uiEventAddHandler(uiEvent *e, uiEventHandler handler, void *sender, void *data);
 uiprivExtern void uiEventDeleteHandler(uiEvent *e, int id);
 uiprivExtern void uiEventFire(uiEvent *e, void *sender, void *args);