plans

TODO.md

@@ -5,6 +5,18 @@
 - userdata support
 - get rid of component signals (useless)
 
+## Userdata system
+
+The idea is that the computer stores userdata as structs which have a pointer (the state) and a bound-component address.
+When a component is removed, all of its associated userdata is instantly dropped.
+For serialization, the userdata pushes a string storing the encoded byte buffer.
+For deserialization, the userdata pops a string and decodes it.
+
+To get component methods, requests are sent to get method info by index, and a NULL name means method is not allowed for that
+particular userdata. Methods can obviously be invoked just like component data.
+Serialization pushes the string on the stack, deserialization gets the buffer as ptr + len and sets the state pointer.
+They are handled by components, thus if it is not mounted at deserialization time, the deserialization fails.
+
 # To re-evaluate
 
 - Exposing the internal non-resizing hashmap implementation.

src/luaarch.c

@@ -73,6 +73,9 @@ static nn_Exit luaArch_luaToNN(luaArch *arch, lua_State *L, int luaIdx) {
 	if(lua_isboolean(L, luaIdx)) {
 		return nn_pushbool(C, lua_toboolean(L, luaIdx));
 	}
+	if(lua_isuserdata(L, luaIdx)) {
+		return nn_pushuserdata(C, (size_t)lua_touserdata(L, luaIdx));
+	}
 	luaL_error(L, "bad Lua value: %s", luaL_typename(L, luaIdx));
 	return NN_EBADSTATE;
 }
@@ -112,6 +115,10 @@ static void luaArch_nnToLua(luaArch *arch, lua_State *L, size_t nnIdx) {
 		nn_popn(C, len * 2);
 		return;
 	}
+	if(nn_isuserdata(C, nnIdx)) {
+		lua_pushlightuserdata(L, (void *)nn_touserdata(C, nnIdx));
+		return;
+	}
 
 	luaL_error(L, "bad NN value: %s", nn_typenameof(C, nnIdx));
 }
@@ -734,8 +741,11 @@ static nn_Exit luaArch_handler(nn_ArchitectureRequest *req) {
 			return NN_OK;
 		}
 		return NN_OK;
-	default:
-		break;
+	case NN_ARCH_SERIALIZE:
+		return nn_pushstring(computer, "lua stuff");
+	case NN_ARCH_DESERIALIZE:
+		// do nothing
+		return NN_OK;
 	}
 	return NN_OK;
 }

src/neonucleus.c

@@ -1645,7 +1645,7 @@ nn_Exit nn_deserializeComputer(nn_Computer *computer, const char *buf, size_t bu
 	return computer->arch.handler(&req);
 }
 
-nn_Exit nn_serializeComputer(nn_Computer *computer, char **buf, size_t *buflen) {
+nn_Exit nn_serializeComputer(nn_Computer *computer) {
 	nn_ArchitectureRequest req;
 	req.computer = computer;
 	req.action = NN_ARCH_SERIALIZE;
@@ -1655,24 +1655,9 @@ nn_Exit nn_serializeComputer(nn_Computer *computer, char **buf, size_t *buflen)
 	nn_Exit e = computer->arch.handler(&req);
 	if(e) return e;
 
-	*buf = req.memOut;
-	*buflen = req.memLen;
-
 	return NN_OK;
 }
 
-nn_Exit nn_freeSerializedComputer(nn_Computer *computer, char *buf, size_t buflen) {
-	nn_ArchitectureRequest req;
-	req.computer = computer;
-	req.action = NN_ARCH_DROPSERIALIZED;
-	req.globalState = computer->arch.state;
-	req.localState = computer->archState;
-	req.memOut = buf;
-	req.memLen = buflen;
-	
-	return computer->arch.handler(&req);
-}
-
 void nn_setError(nn_Computer *computer, const char *s) {
 	nn_setLError(computer, s, nn_strlen(s));
 }

src/neonucleus.h

@@ -350,12 +350,10 @@ typedef enum nn_ArchitectureAction {
 	NN_ARCH_TICK,
 	// get the free memory
 	NN_ARCH_FREEMEM,
-	// deserialize from an encoded state
+	// deserialize from an encoded state, passed into request.
 	NN_ARCH_DESERIALIZE,
-	// serialize to an encoded state
+	// serialize to an encoded state, pushed it as a string
 	NN_ARCH_SERIALIZE,
-	// drop the encoded buffer
-	NN_ARCH_DROPSERIALIZED,
 } nn_ArchitectureAction;
 
 typedef struct nn_ArchitectureRequest {
@@ -373,12 +371,9 @@ typedef struct nn_ArchitectureRequest {
 		bool synchronized;
 		// in the case of NN_ARCH_FREEMEM, the free memory
 		size_t freeMemory;
-		// in the case of NN_ARCH_DESERIALIZE, NN_ARCH_SERIALIZE and NN_ARCH_DROPSERIALIZED, the buffer.
+		// in the case of NN_ARCH_DESERIALIZE, the buffer.
 		struct {
-			union {
-				char *memOut;
 			const char *memIn;
-			};
 			size_t memLen;
 		};
 	};
@@ -540,14 +535,13 @@ double nn_getUptime(nn_Computer *computer);
 
 // Deserialize an encoded computer state.
 // Encoding depends on architecture.
+// Will push it as a string and then call the architecture, which will decode it and pop it.
 nn_Exit nn_deserializeComputer(nn_Computer *computer, const char *buf, size_t buflen);
 
 // Serialize the computer state.
 // Encoding depends on architecture.
-nn_Exit nn_serializeComputer(nn_Computer *computer, char **buf, size_t *buflen);
-
-// Free the serialized buffer.
-nn_Exit nn_freeSerializedComputer(nn_Computer *computer, char *buf, size_t buflen);
+// Pushes the output, if successful, as a string on the stack.
+nn_Exit nn_serializeComputer(nn_Computer *computer);
 
 // address is copied.
 // It can be NULL if you wish to have no tmp address.
@@ -771,8 +765,8 @@ void nn_getComponents(nn_Computer *c, const char **components);
 // invoke the component method.
 // Everything on-stack is taken as an argument.
 // Will pop off trailing nulls.
-// Every remaining is what the component returned.
-// In the case of 
+// Every remaining stack value is what the component returned.
+// In the case of errors, the contents of the stack is undefined
 nn_Exit nn_invokeComponent(nn_Computer *computer, const char *compAddress, const char *method);
 
 // send a signal to a component.
@@ -780,6 +774,40 @@ nn_Exit nn_invokeComponent(nn_Computer *computer, const char *compAddress, const
 // assumes one is specified.
 nn_Exit nn_signalComponent(nn_Component *component, nn_Computer *computer, const char *signal);
 
+// Userdata!!!!
+
+// Allocates a userdata index. Returns -1 on failure or if there are too many.
+int nn_allocUserdata(nn_Computer *computer, void *state, const char *compAddress);
+
+// Frees a userdata index.
+void nn_freeUserdata(nn_Computer *computer, size_t userdata);
+
+// Returns whether the userdata index is valid
+bool nn_isUserdataValid(nn_Computer *computer, size_t userdata);
+
+// If compAddress is correct and userdata is valid, returns the state pointer.
+// If not, returns NULL, to prevent UB.
+void *nn_unwrapUserdata(nn_Computer *computer, size_t userdata, const char *compAddress);
+
+// gets the component address which manages this userdata
+const char *nn_getUserdataComponent(nn_Computer *computer, size_t userdata);
+
+// Gets information about a method of this userdata, by index.
+// If idx is out of bounds, this returns true, which means to stop iteration.
+// If method->name is NULL, the method should be skipped.
+bool nn_getUserdataMethod(nn_Computer *computer, size_t userdata, size_t idx, nn_Method *method);
+
+// Invokes a method on some userdata, same semantics as nn_invokeComponent
+nn_Exit nn_invokeUserdata(nn_Computer *computer, size_t userdata, const char *method);
+
+// Serializes the userdata into a buffer and pushes it as a string.
+// Make sure to keep track of its index and component address!
+nn_Exit nn_serializeUserdata(nn_Computer *computer, size_t userdata);
+
+// Deserializes userdata at a particular index.
+// NOTE: if the component does not exist, or the userdata index is already taken, this errors.
+nn_Exit nn_deserializeUserdata(nn_Computer *computer, size_t userdata, const char *compAddress, const char *buf, size_t len);
+
 // Sets the call budget.
 // The default is 1,000.
 void nn_setCallBudget(nn_Computer *computer, size_t budget);