// 15 may 2019 #include "uipriv.h" struct handler { int id; uiEventHandler f; void *sender; void *data; bool blocked; }; static int handlerCmp(const void *a, const void *b) { const struct handler *ha = (const struct handler *) a; const struct handler *hb = (const struct handler *) b; // This could be ha->id - hb->id, but let's do it the explicit way to avoid integer overflow/underflow. if (ha->id < hb->id) return -1; if (ha->id > hb->id) return 1; return 0; } struct uiEvent { uiEventOptions opts; uiprivArray handlers; uiprivArray unusedIDs; bool firing; }; uiEvent *uiNewEvent(const uiEventOptions *options) { uiEvent *e; if (!uiprivCheckInitializedAndThread()) return NULL; if (options == NULL) { uiprivProgrammerError(uiprivProgrammerErrorNullPointer, "uiEventOptions", uiprivFunc); return NULL; } if (options->Size != sizeof (uiEventOptions)) { uiprivProgrammerError(uiprivProgrammerErrorWrongStructSize, options->Size, "uiEventOptions"); return NULL; } e = (uiEvent *) uiprivAlloc(sizeof (uiEvent), "uiEvent"); e->opts = *options; uiprivArrayInit(e->handlers, struct handler, 32, "uiEvent handlers"); uiprivArrayInit(e->unusedIDs, int, 32, "uiEvent handler unused IDs"); return e; } #define checkEventNonnull(e, ret) if ((e) == NULL) { \ uiprivProgrammerError(uiprivProgrammerErrorNullPointer, "uiEvent", uiprivFunc); \ return ret; \ } #define checkEventNotFiring(e, ret) if ((e)->firing) { \ uiprivProgrammerError(uiprivProgrammerErrorChangingEventDuringFire, uiprivFunc); \ return ret; \ } static bool checkEventSender(const uiEvent *e, void *sender, const char *func) { if (e->opts.Global && sender != NULL) { uiprivProgrammerError(uiprivProgrammerErrorBadSenderForEvent, "non-NULL", "global", func); return false; } if (!e->opts.Global && sender == NULL) { uiprivProgrammerError(uiprivProgrammerErrorBadSenderForEvent, "NULL", "non-global", func); return false; } return true; } int uiEventAddHandler(uiEvent *e, uiEventHandler handler, void *sender, void *data) { struct handler *h; int id; if (!uiprivCheckInitializedAndThread()) return 0; checkEventNonnull(e, 0); checkEventNotFiring(e, 0); if (handler == NULL) { uiprivProgrammerError(uiprivProgrammerErrorNullPointer, "uiEventHandler", uiprivFunc); return 0; } if (!checkEventSender(e, sender, uiprivFunc)) return 0; id = 0; if (e->unusedIDs.len > 0) { int *p; p = uiprivArrayAt(e->unusedIDs, int, e->unusedIDs.len - 1); id = *p; uiprivArrayDeleteItem(&(e->unusedIDs), p, 1); } else if (e->handlers.len != 0) id = uiprivArrayAt(e->handlers, struct handler, e->handlers.len - 1)->id + 1; h = (struct handler *) uiprivArrayAppend(&(e->handlers), 1); h->id = id; h->f = handler; h->sender = sender; h->data = data; uiprivArrayQsort(&(e->handlers), handlerCmp); return id; } static struct handler *findHandler(const uiEvent *e, int id, const char *func) { struct handler key; struct handler *ret; memset(&key, 0, sizeof (struct handler)); key.id = id; ret = (struct handler *) uiprivArrayBsearch(&(e->handlers), &key, handlerCmp); if (ret == NULL) uiprivProgrammerError(uiprivProgrammerErrorIntIDNotFound, "uiEvent handler", id, func); return ret; } void uiEventDeleteHandler(uiEvent *e, int id) { struct handler *h; if (!uiprivCheckInitializedAndThread()) return; checkEventNonnull(e, /* nothing */); checkEventNotFiring(e, /* nothing */); h = findHandler(e, id, uiprivFunc); if (h == NULL) return; uiprivArrayDeleteItem(&(e->handlers), h, 1); *((int *) uiprivArrayAppend(&(e->unusedIDs), 1)) = id; } void uiEventFire(uiEvent *e, void *sender, void *args) { struct handler *h; size_t i; if (!uiprivCheckInitializedAndThread()) return; checkEventNonnull(e, /* nothing */); if (e->firing) { uiprivProgrammerError(uiprivProgrammerErrorRecursiveEventFire); return; } if (!checkEventSender(e, sender, uiprivFunc)) return; e->firing = true; h = (struct handler *) (e->handlers.buf); for (i = 0; i < e->handlers.len; i++) { if (h->sender == sender && !h->blocked) (*(h->f))(sender, args, h->data); h++; } e->firing = false; } bool uiEventHandlerBlocked(const uiEvent *e, int id) { struct handler *h; if (!uiprivCheckInitializedAndThread()) return false; checkEventNonnull(e, false); h = findHandler(e, id, uiprivFunc); if (h == NULL) return false; return h->blocked; } void uiEventSetHandlerBlocked(uiEvent *e, int id, bool blocked) { struct handler *h; if (!uiprivCheckInitializedAndThread()) return; checkEventNonnull(e, /* nothing */); checkEventNotFiring(e, /* nothing */); h = findHandler(e, id, uiprivFunc); if (h == NULL) return; h->blocked = blocked; }