C++ duk_remove函数代码示例

    static Box * PrivatePush( duk_context * ctx, const size_t class_index, const size_t object_size, finalizer_t finalizer )
    {
        duk_push_global_object( ctx );
        duk_get_prop_string( ctx, -1, "Proxy" );
        duk_remove( ctx, -2 );

        duk_push_object( ctx );

        size_t require_size = sizeof( Box ) + object_size;

        Box * box = reinterpret_cast<Box*>( duk_push_fixed_buffer( ctx, require_size ) );
        box->ClassIndex = class_index;
        box->Finalizer = finalizer;

        duk_put_prop_string( ctx, -2, "\xFF" "Box" );

        duk_push_c_function( ctx, &internal::ClassFinalizer, 1 );
        duk_set_finalizer( ctx, -2 );

        duk_push_heap_stash( ctx );
        duk_get_prop_string( ctx, -1, "InstanceHandler" );
        duk_remove( ctx, -2 );
        duk_new( ctx, 2 );

        return box;
    }

void
duk_push_sphere_bytearray(duk_context* ctx, bytearray_t* array)
{
	duk_push_object(ctx);
	duk_push_string(ctx, "bytearray"); duk_put_prop_string(ctx, -2, "\xFF" "sphere_type");
	duk_push_pointer(ctx, array); duk_put_prop_string(ctx, -2, "\xFF" "ptr");
	duk_push_c_function(ctx, js_ByteArray_finalize, DUK_VARARGS); duk_set_finalizer(ctx, -2);
	duk_push_c_function(ctx, js_ByteArray_toString, DUK_VARARGS); duk_put_prop_string(ctx, -2, "toString");
	duk_push_c_function(ctx, js_ByteArray_concat, DUK_VARARGS); duk_put_prop_string(ctx, -2, "concat");
	duk_push_c_function(ctx, js_ByteArray_slice, DUK_VARARGS); duk_put_prop_string(ctx, -2, "slice");
	duk_push_string(ctx, "length"); duk_push_int(ctx, array->size);
	duk_def_prop(ctx, -3,
		DUK_DEFPROP_HAVE_CONFIGURABLE | 0
		| DUK_DEFPROP_HAVE_WRITABLE | 0
		| DUK_DEFPROP_HAVE_VALUE);

	// return proxy object so we can catch array accesses
	duk_push_global_object(ctx);
	duk_get_prop_string(ctx, -1, "Proxy");
	duk_dup(ctx, -3);
	duk_push_object(ctx);
	duk_push_c_function(ctx, js_ByteArray_getProp, DUK_VARARGS); duk_put_prop_string(ctx, -2, "get");
	duk_push_c_function(ctx, js_ByteArray_setProp, DUK_VARARGS); duk_put_prop_string(ctx, -2, "set");
	duk_new(ctx, 2);
	duk_remove(ctx, -2);
	duk_remove(ctx, -2);
}

void PushWeakObject(duk_context* ctx, Object* object)
{
    if (!object)
    {
        duk_push_null(ctx);
        return;
    }

    duk_push_heap_stash(ctx);

    // Check if the wrapper for the object already exists in stash
    // This is required so that comparisons of object references (e.g. against the me property) work properly
    if (duk_has_prop_index(ctx, -1, (size_t)object))
    {
        duk_get_prop_index(ctx, -1, (size_t)object);
        WeakPtr<Object>* oldPtr = GetWeakPtr(ctx, -1);
        if (oldPtr && oldPtr->Get() == object)
        {
            duk_remove(ctx, -2); // Remove stash
            return;
        }
        else
            duk_pop(ctx); // Valid existing wrapper not found
    }

    duk_push_object(ctx);
    WeakPtr<Object>* ptr = new WeakPtr<Object>(object);
    duk_push_pointer(ctx, ptr);
    duk_put_prop_string(ctx, -2, "\xff""weak");
    duk_push_c_function(ctx, WeakPtr_Finalizer, 1);
    duk_set_finalizer(ctx, -2);

    // Set prototype. If not found, use base class prototype (e.g. IComponent)
    duk_get_global_string(ctx, object->GetTypeName().CString());
    if (!duk_is_object(ctx, -1))
    {
        duk_pop(ctx);
        duk_get_global_string(ctx, object->GetTypeInfo()->GetBaseTypeInfo()->GetTypeName().CString());
    }
    duk_get_prop_string(ctx, -1, "prototype");
    duk_set_prototype(ctx, -3);
    duk_pop(ctx);

    // Proxied property access handling for scene, entity & component
    if (object->GetType() == Scene::GetTypeStatic())
        SetupProxy(ctx, SceneProxyFunctions);
    if (object->GetType() == Entity::GetTypeStatic())
        SetupProxy(ctx, EntityProxyFunctions);
    else if (dynamic_cast<IComponent*>(object))
        SetupProxy(ctx, ComponentProxyFunctions);

    // Store to stash
    duk_dup(ctx, -1);
    duk_put_prop_index(ctx, -3, (size_t)object);
    duk_remove(ctx, -2); // Remove stash
}

static duk_ret_t test_3(duk_context *ctx) {
    prep(ctx);
    duk_remove(ctx, 0);   /* -> [ 234 345 ]  (legal) */
    printf("remove at 0 ok\n");
    duk_remove(ctx, -2);  /* -> [ 345 ]  (legal) */
    printf("remove at -2 ok\n");
    duk_remove(ctx, -2);   /* (illegal) */
    printf("remove at -2 ok\n");
    return 0;
}

static duk_ret_t test_2(duk_context *ctx) {
    prep(ctx);
    duk_remove(ctx, 2);   /* -> [ 123 234 ]  (legal) */
    printf("remove at 2 ok\n");
    duk_remove(ctx, -1);  /* -> [ 123 ]  (legal) */
    printf("remove at -1 ok\n");
    duk_remove(ctx, 1);   /* (illegal) */
    printf("remove at 1 ok\n");
    return 0;
}

void SetupProxy(duk_context* ctx, const duk_function_list_entry* funcs)
{
    duk_push_global_object(ctx);
    duk_get_prop_string(ctx, -1, "Proxy");
    duk_dup(ctx, -3); // Duplicate target at stack top
    duk_remove(ctx, -4); // Remove original target
    duk_push_object(ctx); // Handler
    duk_put_function_list(ctx, -1, funcs);
    duk_new(ctx, 2); // Create proxy
    duk_remove(ctx, -2); // Remove global object
}

static duk_bool_t duk__get_cached_module(duk_context *ctx, const char *id) {
	duk_push_global_stash(ctx);
	(void) duk_get_prop_string(ctx, -1, "\xff" "requireCache");
	if (duk_get_prop_string(ctx, -1, id)) {
		duk_remove(ctx, -2);
		duk_remove(ctx, -2);
		return 1;
	} else {
		duk_pop_3(ctx);
		return 0;
	}
}

void
mn_push_ref(duk_context *ctx, int ref) {
	if (!ref) {
		duk_push_undefined(ctx);
		return;
	}
	/* Get the "refs" array in the heap stash */
	duk_push_heap_stash(ctx);
	duk_get_prop_string(ctx, -1, "refs");
	duk_remove(ctx, -2);

	duk_get_prop_index(ctx, -1, ref);

	duk_remove(ctx, -2);
}

// Assumes nargs are the top of the stack.  Rest comes from request
// Return value is not left on the stack.
void duv_resolve(uv_req_t* req, int nargs) {
  duk_context *ctx = req->data;
  duv_push_handle(ctx, req);
  // stack: args... obj
  duk_get_prop_string(ctx, -1, "\xff""uv-callback");
  // stack: args... obj callback
  duk_del_prop_string(ctx, -2, "\xff""uv-callback");
  // stack: args... obj callback

  if (!duk_is_function(ctx, -1)) {
    // stack: args... obj callback
    duk_pop_n(ctx, 2 + nargs);
    return;
  }
  duk_remove(ctx, -2);
  // stack: args... callback
  duk_insert(ctx, -(nargs + 1));
  // stack: callback args...
  duk_call(ctx, nargs);
  // stack: result
  duk_pop(ctx);

  // Remove the request from the GC roots
  duv_remove_handle(ctx, req);
}

duk_ret_t duv_setup_request(duk_context *ctx, uv_req_t* req, int callback) {
  // Create a new container object for the request with request methods
  duk_push_object(ctx);
  duk_push_heap_stash(ctx);
  duk_get_prop_string(ctx, -1, "req-prototype");
  duk_remove(ctx, -2);
  duk_set_prototype(ctx, -2);

  // Set buffer as uv-data internal property.
  duk_insert(ctx, -2);
  duk_put_prop_string(ctx, -2, "\xff""uv-data");

  // Store the request type.
  duk_push_int(ctx, req->type);
  duk_put_prop_string(ctx, -2, "\xff""req-type");

  // Store a reference to the lua callback
  duk_dup(ctx, callback);
  duk_put_prop_string(ctx, -2, "\xff""uv-callback");

  // Store this object in the heap stack keyed by the request's pointer address.
  // This will prevent it from being garbage collected and allow us to find
  // it with nothing more than the request's address.
  duv_store_handle(ctx, req);

  // Store the context in the handle so it can use duktape APIs.
  req->data = ctx;

  // TODO: is this still on the stack?
  return 1;
}

static duk_double_t duk__push_this_number_plain(duk_context *ctx) {
	duk_hobject *h;

	/* Number built-in accepts a plain number or a Number object (whose
	 * internal value is operated on).  Other types cause TypeError.
	 */

	duk_push_this(ctx);
	if (duk_is_number(ctx, -1)) {
		DUK_DDD(DUK_DDDPRINT("plain number value: %!T", (duk_tval *) duk_get_tval(ctx, -1)));
		goto done;
	}
	h = duk_get_hobject(ctx, -1);
	if (!h || 
	    (DUK_HOBJECT_GET_CLASS_NUMBER(h) != DUK_HOBJECT_CLASS_NUMBER)) {
		DUK_DDD(DUK_DDDPRINT("unacceptable this value: %!T", (duk_tval *) duk_get_tval(ctx, -1)));
		DUK_ERROR((duk_hthread *) ctx, DUK_ERR_TYPE_ERROR, "expected a number");
	}
	duk_get_prop_stridx(ctx, -1, DUK_STRIDX_INT_VALUE);
	DUK_ASSERT(duk_is_number(ctx, -1));
	DUK_DDD(DUK_DDDPRINT("number object: %!T, internal value: %!T",
	                     (duk_tval *) duk_get_tval(ctx, -2), (duk_tval *) duk_get_tval(ctx, -1)));
	duk_remove(ctx, -2);

 done:
	return duk_get_number(ctx, -1);
}

bool StyleContext::evalFunction(FunctionID id) {
    // Get all functions (array) in context
    if (!duk_get_global_string(m_ctx, FUNC_ID)) {
        LOGE("EvalFilterFn - functions array not initialized");
        duk_pop(m_ctx); // pop [undefined] sitting at stack top
        return false;
    }

    // Get function at index `id` from functions array, put it at stack top
    if (!duk_get_prop_index(m_ctx, -1, id)) {
        LOGE("EvalFilterFn - function %d not set", id);
        duk_pop(m_ctx); // pop "undefined" sitting at stack top
        duk_pop(m_ctx); // pop functions (array) now sitting at stack top
        return false;
    }

    // pop fns array
    duk_remove(m_ctx, -2);

    // call popped function (sitting at stack top), evaluated value is put on stack top
    if (duk_pcall(m_ctx, 0) != 0) {
        LOGE("EvalFilterFn: %s", duk_safe_to_string(m_ctx, -1));
        duk_pop(m_ctx);
        return false;
    }

    return true;
}

DUK_EXTERNAL void duk_dump_function(duk_context *ctx) {
	duk_hthread *thr;
	duk_hcompiledfunction *func;
	duk_bufwriter_ctx bw_ctx_alloc;
	duk_bufwriter_ctx *bw_ctx = &bw_ctx_alloc;
	duk_uint8_t *p;

	DUK_ASSERT(ctx != NULL);
	thr = (duk_hthread *) ctx;

	/* Bound functions don't have all properties so we'd either need to
	 * lookup the non-bound target function or reject bound functions.
	 * For now, bound functions are rejected.
	 */
	func = duk_require_hcompiledfunction(ctx, -1);
	DUK_ASSERT(func != NULL);
	DUK_ASSERT(!DUK_HOBJECT_HAS_BOUND(&func->obj));

	/* Estimating the result size beforehand would be costly, so
	 * start with a reasonable size and extend as needed.
	 */
	DUK_BW_INIT_PUSHBUF(thr, bw_ctx, DUK__BYTECODE_INITIAL_ALLOC);
	p = DUK_BW_GET_PTR(thr, bw_ctx);
	*p++ = DUK__SER_MARKER;
	*p++ = DUK__SER_VERSION;
	p = duk__dump_func(ctx, func, bw_ctx, p);
	DUK_BW_SET_PTR(thr, bw_ctx, p);
	DUK_BW_COMPACT(thr, bw_ctx);

	DUK_DD(DUK_DDPRINT("serialized result: %!T", duk_get_tval(ctx, -1)));

	duk_remove(ctx, -2);  /* [ ... func buf ] -> [ ... buf ] */
}

 void OnSignal(Entity * param0, Entity * param1, const float3 & param2, const float3 & param3, float param4, float param5, bool param6)
 {
     duk_context* ctx = ctx_;
     duk_push_global_object(ctx);
     duk_get_prop_string(ctx, -1, "_OnSignal");
     duk_remove(ctx, -2);
     duk_push_number(ctx, (size_t)key_);
     duk_push_array(ctx);
     PushWeakObject(ctx, param0);
     duk_put_prop_index(ctx, -2, 0);
     PushWeakObject(ctx, param1);
     duk_put_prop_index(ctx, -2, 1);
     PushValueObjectCopy<float3>(ctx, param2, float3_ID, float3_Finalizer);
     duk_put_prop_index(ctx, -2, 2);
     PushValueObjectCopy<float3>(ctx, param3, float3_ID, float3_Finalizer);
     duk_put_prop_index(ctx, -2, 3);
     duk_push_number(ctx, param4);
     duk_put_prop_index(ctx, -2, 4);
     duk_push_number(ctx, param5);
     duk_put_prop_index(ctx, -2, 5);
     duk_push_boolean(ctx, param6);
     duk_put_prop_index(ctx, -2, 6);
     bool success = duk_pcall(ctx, 2) == 0;
     if (!success) LogError("[JavaScript] OnSignal: " + GetErrorString(ctx));
     duk_pop(ctx);
 }

/*
 * Called with a service object on the top of the stack. Returns with a message object on top of
 * the stack replacing the service object.
 */
static void MessageSetup(duk_context* ctx, const char* iface, const char* member, const char* path, uint8_t msgType)
{
    AJ_Status status;
    AJ_MsgHeader hdr;
    AJ_Message msg;
    AJS_MsgInfo* msgInfo;
    const char* dest;
    uint8_t secure;
    size_t dlen;
    duk_idx_t objIdx = duk_push_object(ctx);

    /*
     * Get the destination from the service object
     */
    duk_get_prop_string(ctx, -2, "dest");
    dest = duk_get_lstring(ctx, -1, &dlen);
    duk_pop(ctx);
    /*
     * If this is not a broadcast message make sure the destination peer is still connected
     */
    if (dlen) {
        CheckPeerIsAlive(ctx, dest);
    }
    /*
     * Initialize a message struct so we can lookup the message id. We do this now because it is
     * alot more efficient if the method object we are creating is used multiple times.
     */
    memset(&msg, 0, sizeof(AJ_Message));
    memset(&hdr, 0, sizeof(AJ_MsgHeader));
    msg.hdr = &hdr;
    msg.signature = "*";
    msg.member = member;
    msg.iface = iface;
    msg.objPath = path ? path : AJS_GetStringProp(ctx, -2, "path");
    /*
     * This allows us to use one object table entry for all messages
     */
    AJS_SetObjectPath(msg.objPath);
    hdr.msgType = msgType;
    status = AJ_LookupMessageId(&msg, &secure);
    if (status != AJ_OK) {
        duk_error(ctx, DUK_ERR_REFERENCE_ERROR, "Unknown %s %s", path ? "SIGNAL" : "METHOD", member);
    }
    /*
     * Buffer to caching message information stored in the "info" property on the method object
     */
    msgInfo = duk_push_fixed_buffer(ctx, sizeof(AJS_MsgInfo) + dlen + 1);
    msgInfo->secure = secure;
    msgInfo->session = AJS_GetIntProp(ctx, -2, "session");
    msgInfo->msgId = msg.msgId;
    memcpy(msgInfo->dest, dest, dlen);
    msgInfo->dest[dlen] = 0;
    duk_put_prop_string(ctx, objIdx, "info");

    AJ_ASSERT(duk_get_top_index(ctx) == objIdx);
    /*
     * Remove sessions object and leave the message object on the top of the stack
     */
    duk_remove(ctx, -2);
}