pkev: unregister callbacks

1 files changed, 71 insertions, 26 deletions

diff --git a/pkev.h b/pkev.h
index fcf0d2d..445180d 100644
--- a/pkev.h
+++ b/pkev.h
@@ -5,6 +5,7 @@
 
 typedef uint64_t pk_ev_mgr_id_T;
 typedef uint64_t pk_ev_id_T;
+typedef uint64_t pk_ev_cb_id_T;
 
 // note: pk_ev_init() is NOT thread-safe
 void pk_ev_init();
@@ -17,9 +18,11 @@ void pk_ev_destroy_mgr(pk_ev_mgr_id_T evmgr);
 typedef void (pk_ev_cb_fn)(void *user_event_data, void *user_cb_data, void *user_ev_data);
 
 pk_ev_id_T pk_ev_register_ev(pk_ev_mgr_id_T evmgr, void *user_ev_data);
-bool pk_ev_register_cb(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, pk_ev_cb_fn *cb, void *user_cb_data);
+pk_ev_cb_id_T pk_ev_register_cb(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, pk_ev_cb_fn *cb, void *user_cb_data);
 void pk_ev_emit(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, void *user_emit_data);
 
+void pk_ev_unregister_cb(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, pk_ev_cb_id_T cbid);
+
 #endif /* PK_EV_H */
 
 #ifdef PK_IMPL_EV
@@ -58,14 +61,17 @@ struct pk_ev_cb {
 struct pk_ev {
 	struct pk_ev_cb *ev_cbs;
 	void *user_ev_data;
-	atomic_uint_fast8_t n_ev_cbs;
+	atomic_uint_fast64_t left_ev_cbs;
+	atomic_uint_fast64_t right_ev_cbs;
 };
 
 struct pk_ev_mgr {
 	struct pk_ev *ev;
-	atomic_uint_fast8_t n_ev;
-	atomic_uint_fast8_t rn_ev;
-	atomic_uint_fast8_t rn_cb;
+	atomic_uint_fast64_t n_ev;
+	// reserved length of `pk_ev`s on this struct
+	atomic_uint_fast64_t rn_ev;
+	// on any given `pk_ev`, the number of callbacks reserved
+	atomic_uint_fast64_t rn_cb;
 };
 
 struct pk_ev_mstr {
@@ -115,7 +121,7 @@ pk_ev_inner_ev_mgr_create(uint64_t ev_count, uint64_t cb_count)
 {
 	assert(ev_count < 0x100);
 	assert(cb_count < 0x100);
-	int i;
+	uint64_t i;
 	struct pk_ev *ev;
 	size_t sz = sizeof(struct pk_ev_mgr) + ((sizeof(struct pk_ev) * ev_count)) + (sizeof (struct pk_ev_cb) * ev_count * cb_count);
 	size_t sz_ev = (sizeof(struct pk_ev_cb) * cb_count);
@@ -130,7 +136,8 @@ pk_ev_inner_ev_mgr_create(uint64_t ev_count, uint64_t cb_count)
 	atomic_init(&mgr->n_ev, 0);
 	for (i = 0; i < mgr->rn_ev; ++i) {
 		ev = &mgr->ev[i];
-		atomic_init(&ev->n_ev_cbs, 0);
+		atomic_init(&ev->left_ev_cbs, 0);
+		atomic_init(&ev->right_ev_cbs, 0);
 		ev->ev_cbs = (struct pk_ev_cb*)(((char *)mgr) + sizeof(struct pk_ev_mgr) + sz_evs + (sz_ev * i));
 	}
 
@@ -141,15 +148,15 @@ early_exit:
 static void
 pk_ev_inner_ev_mgr_clone(struct pk_ev_mgr *old, struct pk_ev_mgr *mgr)
 {
-	int i;
+	uint64_t i;
 	struct pk_ev *ev_old;
 	struct pk_ev *ev;
 	atomic_store(&mgr->n_ev, atomic_load(&old->n_ev));
 	for (i = 0; i < old->n_ev; ++i) {
 		ev_old = &old->ev[i];
 		ev = &mgr->ev[i];
-		memcpy(ev->ev_cbs, ev_old->ev_cbs, sizeof(struct pk_ev_cb) * atomic_load(&ev_old->n_ev_cbs));
-		atomic_store(&ev->n_ev_cbs, atomic_load(&ev_old->n_ev_cbs));
+		memcpy(ev->ev_cbs, ev_old->ev_cbs, sizeof(struct pk_ev_cb) * atomic_load(&ev_old->right_ev_cbs));
+		atomic_store(&ev->right_ev_cbs, atomic_load(&ev_old->right_ev_cbs));
 	}
 }
 
@@ -221,31 +228,55 @@ pk_ev_register_ev(pk_ev_mgr_id_T evmgr, void *user_ev_data)
 	return id;
 }
 
-bool
+pk_ev_cb_id_T
 pk_ev_register_cb(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, pk_ev_cb_fn *cb, void *user_cb_data)
 {
 	assert(evmgr < 64);
-	uint64_t new_size;
+	bool found = false;
+	uint64_t new_size, i;
 	struct pk_ev_mgr *mgr;
-	uint8_t cb_index;
+	pk_ev_cb_id_T cb_index;
+
+	mgr = pk_ev_mstr.mgrs[evmgr];
+	if (mgr == nullptr) {
+		PK_LOGV_ERR("[pkev.h] unknown event: '%lu'.\n", evmgr);
+		exit(1);
+	}
 	mtx_lock(&pk_ev_mstr.mtxs[evmgr]);
-	if (pk_ev_mstr.mgrs[evmgr]->ev[evid].n_ev_cbs == pk_ev_mstr.mgrs[evmgr]->rn_cb) {
-		new_size = PK_MAX(2, PK_MIN(255, pk_ev_mstr.mgrs[evmgr]->rn_cb * PK_EV_GROW_RATIO));
-		if (new_size == pk_ev_mstr.mgrs[evmgr]->rn_cb) {
-			PK_LOG_ERR("[pkev.h] need more room, but failed to grow cb count.\n");
-			mtx_unlock(&pk_ev_mstr.mtxs[evmgr]);
-			exit(1);
+	for (i = mgr->ev[evid].left_ev_cbs; i < mgr->ev[evid].right_ev_cbs; ++i) {
+		if (found == false && mgr->ev[evid].ev_cbs[i].cb != nullptr) {
+			found = true;
+			cb_index = i;
+			continue;
+		}
+		if (found == false) continue;
+		if (mgr->ev[evid].ev_cbs[i].cb == nullptr) {
+			mgr->ev[evid].left_ev_cbs = i;
+			break;
+		}
+	}
+	if (found == false) {
+		if (pk_ev_mstr.mgrs[evmgr]->ev[evid].right_ev_cbs == pk_ev_mstr.mgrs[evmgr]->rn_cb) {
+			new_size = PK_MAX(2, PK_MIN(255, pk_ev_mstr.mgrs[evmgr]->rn_cb * PK_EV_GROW_RATIO));
+			if (new_size == pk_ev_mstr.mgrs[evmgr]->rn_cb) {
+				PK_LOG_ERR("[pkev.h] need more room, but failed to grow cb count.\n");
+				mtx_unlock(&pk_ev_mstr.mtxs[evmgr]);
+				exit(1);
+			}
+			mgr = pk_ev_inner_ev_mgr_create(pk_ev_mstr.mgrs[evmgr]->rn_ev, new_size);
+			pk_ev_inner_ev_mgr_clone(pk_ev_mstr.mgrs[evmgr], mgr);
+			free(pk_ev_mstr.mgrs[evmgr]);
+			pk_ev_mstr.mgrs[evmgr] = mgr;
+		}
+		cb_index = pk_ev_mstr.mgrs[evmgr]->ev[evid].right_ev_cbs++;
+		if (cb_index == pk_ev_mstr.mgrs[evmgr]->ev[evid].left_ev_cbs) {
+			pk_ev_mstr.mgrs[evmgr]->ev[evid].left_ev_cbs++;
 		}
-		mgr = pk_ev_inner_ev_mgr_create(pk_ev_mstr.mgrs[evmgr]->rn_ev, new_size);
-		pk_ev_inner_ev_mgr_clone(pk_ev_mstr.mgrs[evmgr], mgr);
-		free(pk_ev_mstr.mgrs[evmgr]);
-		pk_ev_mstr.mgrs[evmgr] = mgr;
 	}
-	cb_index = pk_ev_mstr.mgrs[evmgr]->ev[evid].n_ev_cbs++;
 	pk_ev_mstr.mgrs[evmgr]->ev[evid].ev_cbs[cb_index].cb = cb;
 	pk_ev_mstr.mgrs[evmgr]->ev[evid].ev_cbs[cb_index].user_cb_data = user_cb_data;
 	mtx_unlock(&pk_ev_mstr.mtxs[evmgr]);
-	return true;
+	return cb_index;
 }
 
 void
@@ -253,7 +284,9 @@ pk_ev_emit(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, void *user_emit_data)
 {
 	assert(evmgr < 64);
 	uint8_t i;
-	for (i = 0; i < pk_ev_mstr.mgrs[evmgr]->ev[evid].n_ev_cbs; ++i) {
+	for (i = 0; i < pk_ev_mstr.mgrs[evmgr]->ev[evid].right_ev_cbs; ++i) {
+		if (pk_ev_mstr.mgrs[evmgr] == nullptr) continue;
+		if (pk_ev_mstr.mgrs[evmgr]->ev[evid].ev_cbs[i].cb == nullptr) continue;
 		(*pk_ev_mstr.mgrs[evmgr]->ev[evid].ev_cbs[i].cb)(
 			pk_ev_mstr.mgrs[evmgr]->ev[evid].user_ev_data,
 			pk_ev_mstr.mgrs[evmgr]->ev[evid].ev_cbs[i].user_cb_data,
@@ -261,4 +294,16 @@ pk_ev_emit(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, void *user_emit_data)
 	}
 }
 
+void
+pk_ev_unregister_cb(pk_ev_mgr_id_T evmgr, pk_ev_id_T evid, pk_ev_cb_id_T cbid)
+{
+	struct pk_ev_mgr *mgr = pk_ev_mstr.mgrs[evmgr];
+	if (mgr == nullptr) return;
+	if (mgr->ev[evid].left_ev_cbs > cbid) {
+		mgr->ev[evid].left_ev_cbs = cbid;
+	}
+	mgr->ev[evid].ev_cbs[cbid].cb = nullptr;
+	mgr->ev[evid].ev_cbs[cbid].user_cb_data = nullptr;
+}
+
 #endif /* PK_IMPL_EV */