コード例 #1
0
ファイル: duk_api_call.c プロジェクト: harold-b/duktape
DUK_INTERNAL void duk_resolve_nonbound_function(duk_context *ctx) {
	duk_uint_t sanity;
	duk_tval *tv;

	sanity = DUK_HOBJECT_BOUND_CHAIN_SANITY;
	do {
		tv = DUK_GET_TVAL_NEGIDX(ctx, -1);
		if (DUK_TVAL_IS_LIGHTFUNC(tv)) {
			/* Lightweight function: never bound, so terminate. */
			break;
		} else if (DUK_TVAL_IS_OBJECT(tv)) {
			duk_hobject *func;

			func = DUK_TVAL_GET_OBJECT(tv);
			DUK_ASSERT(func != NULL);
			if (!DUK_HOBJECT_IS_CALLABLE(func) || !DUK_HOBJECT_HAS_BOUNDFUNC(func)) {
				break;
			}
			duk_get_prop_stridx_short(ctx, -1, DUK_STRIDX_INT_TARGET);
			duk_replace(ctx, -2);
		} else {
			break;
		}
	} while (--sanity > 0);
}
コード例 #2
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
DUK_INTERNAL duk_hstring *duk_js_typeof(duk_hthread *thr, duk_tval *tv_x) {
	duk_small_int_t stridx = 0;

	switch (DUK_TVAL_GET_TAG(tv_x)) {
	case DUK_TAG_UNDEFINED: {
		stridx = DUK_STRIDX_LC_UNDEFINED;
		break;
	}
	case DUK_TAG_NULL: {
		/* Note: not a typo, "object" is returned for a null value */
		stridx = DUK_STRIDX_LC_OBJECT;
		break;
	}
	case DUK_TAG_BOOLEAN: {
		stridx = DUK_STRIDX_LC_BOOLEAN;
		break;
	}
	case DUK_TAG_POINTER: {
		/* implementation specific */
		stridx = DUK_STRIDX_LC_POINTER;
		break;
	}
	case DUK_TAG_STRING: {
		stridx = DUK_STRIDX_LC_STRING;
		break;
	}
	case DUK_TAG_OBJECT: {
		duk_hobject *obj = DUK_TVAL_GET_OBJECT(tv_x);
		DUK_ASSERT(obj != NULL);
		if (DUK_HOBJECT_IS_CALLABLE(obj)) {
			stridx = DUK_STRIDX_LC_FUNCTION;
		} else {
			stridx = DUK_STRIDX_LC_OBJECT;
		}
		break;
	}
	case DUK_TAG_BUFFER: {
		/* implementation specific */
		stridx = DUK_STRIDX_LC_BUFFER;
		break;
	}
	case DUK_TAG_LIGHTFUNC: {
		stridx = DUK_STRIDX_LC_FUNCTION;
		break;
	}
#if defined(DUK_USE_FASTINT)
	case DUK_TAG_FASTINT:
#endif
	default: {
		/* number */
		DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv_x));
		stridx = DUK_STRIDX_LC_NUMBER;
		break;
	}
	}

	DUK_ASSERT(stridx >= 0 && stridx < DUK_HEAP_NUM_STRINGS);
	return DUK_HTHREAD_GET_STRING(thr, stridx);
}
コード例 #3
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
/*
 *  IsCallable()  (E5 Section 9.11)
 *
 *  XXX: API equivalent is a separate implementation now, and this has
 *  currently no callers.
 */

#if 0  /* unused */
DUK_INTERNAL duk_bool_t duk_js_iscallable(duk_tval *tv_x) {
	duk_hobject *obj;

	if (!DUK_TVAL_IS_OBJECT(tv_x)) {
		return 0;
	}
	obj = DUK_TVAL_GET_OBJECT(tv_x);
	DUK_ASSERT(obj != NULL);

	return DUK_HOBJECT_IS_CALLABLE(obj);
}
コード例 #4
0
ファイル: duk_js_ops.c プロジェクト: remoe/duktape
duk_hstring *duk_js_typeof(duk_hthread *thr, duk_tval *tv_x) {
	int idx = 0;

	switch (DUK_TVAL_GET_TAG(tv_x)) {
	case DUK_TAG_UNDEFINED: {
		idx = DUK_STRIDX_LC_UNDEFINED;
		break;
	}
	case DUK_TAG_NULL: {
		/* Note: not a typo, "object" is returned for a null value */
		idx = DUK_STRIDX_LC_OBJECT;
		break;
	}
	case DUK_TAG_BOOLEAN: {
		idx = DUK_STRIDX_LC_BOOLEAN;
		break;
	}
	case DUK_TAG_POINTER: {
		/* implementation specific */
		idx = DUK_STRIDX_LC_POINTER;
		break;
	}
	case DUK_TAG_STRING: {
		idx = DUK_STRIDX_LC_STRING;
		break;
	}
	case DUK_TAG_OBJECT: {
		duk_hobject *obj = DUK_TVAL_GET_OBJECT(tv_x);
		DUK_ASSERT(obj != NULL);
		if (DUK_HOBJECT_IS_CALLABLE(obj)) {
			idx = DUK_STRIDX_LC_FUNCTION;
		} else {
			idx = DUK_STRIDX_LC_OBJECT;
		}
		break;
	}
	case DUK_TAG_BUFFER: {
		/* implementation specific */
		idx = DUK_STRIDX_LC_BUFFER;
		break;
	}
	default: {
		/* number */
		DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv_x));
		idx = DUK_STRIDX_LC_NUMBER;
		break;
	}
	}

	DUK_ASSERT(idx >= 0 && idx < DUK_HEAP_NUM_STRINGS);
	return thr->strs[idx];
}
コード例 #5
0
ファイル: duk_api_object.c プロジェクト: 3009420/civetweb
/* Object.defineProperty() equivalent C binding. */
DUK_EXTERNAL void duk_def_prop(duk_context *ctx, duk_idx_t obj_index, duk_uint_t flags) {
	duk_hthread *thr = (duk_hthread *) ctx;
	duk_idx_t idx_base;
	duk_hobject *obj;
	duk_hstring *key;
	duk_idx_t idx_value;
	duk_hobject *get;
	duk_hobject *set;
	duk_uint_t is_data_desc;
	duk_uint_t is_acc_desc;

	DUK_ASSERT_CTX_VALID(ctx);

	obj = duk_require_hobject(ctx, obj_index);

	is_data_desc = flags & (DUK_DEFPROP_HAVE_VALUE | DUK_DEFPROP_HAVE_WRITABLE);
	is_acc_desc = flags & (DUK_DEFPROP_HAVE_GETTER | DUK_DEFPROP_HAVE_SETTER);
	if (is_data_desc && is_acc_desc) {
		/* "Have" flags must not be conflicting so that they would
		 * apply to both a plain property and an accessor at the same
		 * time.
		 */
		goto fail_invalid_desc;
	}

	idx_base = duk_get_top_index(ctx);
	if (flags & DUK_DEFPROP_HAVE_SETTER) {
		duk_require_type_mask(ctx, idx_base, DUK_TYPE_MASK_UNDEFINED |
		                                     DUK_TYPE_MASK_OBJECT |
		                                     DUK_TYPE_MASK_LIGHTFUNC);
		set = duk_get_hobject_or_lfunc_coerce(ctx, idx_base);
		if (set != NULL && !DUK_HOBJECT_IS_CALLABLE(set)) {
			goto fail_not_callable;
		}
		idx_base--;
	} else {
		set = NULL;
	}
	if (flags & DUK_DEFPROP_HAVE_GETTER) {
		duk_require_type_mask(ctx, idx_base, DUK_TYPE_MASK_UNDEFINED |
		                                     DUK_TYPE_MASK_OBJECT |
		                                     DUK_TYPE_MASK_LIGHTFUNC);
		get = duk_get_hobject_or_lfunc_coerce(ctx, idx_base);
		if (get != NULL && !DUK_HOBJECT_IS_CALLABLE(get)) {
			goto fail_not_callable;
		}
		idx_base--;
	} else {
		get = NULL;
	}
	if (flags & DUK_DEFPROP_HAVE_VALUE) {
		idx_value = idx_base;
		idx_base--;
	} else {
		idx_value = (duk_idx_t) -1;
	}
	key = duk_require_hstring(ctx, idx_base);

	duk_require_valid_index(ctx, idx_base);

	duk_hobject_define_property_helper(ctx,
	                                   flags /*defprop_flags*/,
	                                   obj,
	                                   key,
	                                   idx_value,
	                                   get,
	                                   set);

	/* Clean up stack */

	duk_set_top(ctx, idx_base);

	/* [ ... obj ... ] */

	return;

 fail_invalid_desc:
	DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, DUK_STR_INVALID_DESCRIPTOR);
	return;

 fail_not_callable:
	DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, DUK_STR_NOT_CALLABLE);
	return;
}
コード例 #6
0
ファイル: duk_api_call.c プロジェクト: harold-b/duktape
DUK_EXTERNAL void duk_new(duk_context *ctx, duk_idx_t nargs) {
	/*
	 *  There are two [[Construct]] operations in the specification:
	 *
	 *    - E5 Section 13.2.2: for Function objects
	 *    - E5 Section 15.3.4.5.2: for "bound" Function objects
	 *
	 *  The chain of bound functions is resolved in Section 15.3.4.5.2,
	 *  with arguments "piling up" until the [[Construct]] internal
	 *  method is called on the final, actual Function object.  Note
	 *  that the "prototype" property is looked up *only* from the
	 *  final object, *before* calling the constructor.
	 *
	 *  Currently we follow the bound function chain here to get the
	 *  "prototype" property value from the final, non-bound function.
	 *  However, we let duk_handle_call() handle the argument "piling"
	 *  when the constructor is called.  The bound function chain is
	 *  thus now processed twice.
	 *
	 *  When constructing new Array instances, an unnecessary object is
	 *  created and discarded now: the standard [[Construct]] creates an
	 *  object, and calls the Array constructor.  The Array constructor
	 *  returns an Array instance, which is used as the result value for
	 *  the "new" operation; the object created before the Array constructor
	 *  call is discarded.
	 *
	 *  This would be easy to fix, e.g. by knowing that the Array constructor
	 *  will always create a replacement object and skip creating the fallback
	 *  object in that case.
	 *
	 *  Note: functions called via "new" need to know they are called as a
	 *  constructor.  For instance, built-in constructors behave differently
	 *  depending on how they are called.
	 */

	/* XXX: merge this with duk_js_call.c, as this function implements
	 * core semantics (or perhaps merge the two files altogether).
	 */

	duk_hthread *thr = (duk_hthread *) ctx;
	duk_hobject *proto;
	duk_hobject *cons;
	duk_hobject *fallback;
	duk_idx_t idx_cons;
	duk_small_uint_t call_flags;

	DUK_ASSERT_CTX_VALID(ctx);

	/* [... constructor arg1 ... argN] */

	idx_cons = duk_require_normalize_index(ctx, -nargs - 1);

	DUK_DDD(DUK_DDDPRINT("top=%ld, nargs=%ld, idx_cons=%ld",
	                     (long) duk_get_top(ctx), (long) nargs, (long) idx_cons));

	/* XXX: code duplication */

	/*
	 *  Figure out the final, non-bound constructor, to get "prototype"
	 *  property.
	 */

	duk_dup(ctx, idx_cons);
	for (;;) {
		duk_tval *tv;
		tv = DUK_GET_TVAL_NEGIDX(ctx, -1);
		DUK_ASSERT(tv != NULL);

		if (DUK_TVAL_IS_OBJECT(tv)) {
			cons = DUK_TVAL_GET_OBJECT(tv);
			DUK_ASSERT(cons != NULL);
			if (!DUK_HOBJECT_IS_CALLABLE(cons) || !DUK_HOBJECT_HAS_CONSTRUCTABLE(cons)) {
				/* Checking callability of the immediate target
				 * is important, same for constructability.
				 * Checking it for functions down the bound
				 * function chain is not strictly necessary
				 * because .bind() should normally reject them.
				 * But it's good to check anyway because it's
				 * technically possible to edit the bound function
				 * chain via internal keys.
				 */
				goto not_constructable;
			}
			if (!DUK_HOBJECT_HAS_BOUNDFUNC(cons)) {
				break;
			}
		} else if (DUK_TVAL_IS_LIGHTFUNC(tv)) {
			/* Lightfuncs cannot be bound. */
			break;
		} else {
			/* Anything else is not constructable. */
			goto not_constructable;
		}
		duk_get_prop_stridx_short(ctx, -1, DUK_STRIDX_INT_TARGET);  /* -> [... cons target] */
		duk_remove_m2(ctx);                                         /* -> [... target] */
	}
	DUK_ASSERT(duk_is_callable(ctx, -1));
	DUK_ASSERT(duk_is_lightfunc(ctx, -1) ||
	           (duk_get_hobject(ctx, -1) != NULL && !DUK_HOBJECT_HAS_BOUNDFUNC(duk_get_hobject(ctx, -1))));

	/* [... constructor arg1 ... argN final_cons] */

	/*
	 *  Create "fallback" object to be used as the object instance,
	 *  unless the constructor returns a replacement value.
	 *  Its internal prototype needs to be set based on "prototype"
	 *  property of the constructor.
	 */

	duk_push_object(ctx);  /* class Object, extensible */

	/* [... constructor arg1 ... argN final_cons fallback] */

	duk_get_prop_stridx_short(ctx, -2, DUK_STRIDX_PROTOTYPE);
	proto = duk_get_hobject(ctx, -1);
	if (!proto) {
		DUK_DDD(DUK_DDDPRINT("constructor has no 'prototype' property, or value not an object "
		                     "-> leave standard Object prototype as fallback prototype"));
	} else {
		DUK_DDD(DUK_DDDPRINT("constructor has 'prototype' property with object value "
		                     "-> set fallback prototype to that value: %!iO", (duk_heaphdr *) proto));
		fallback = duk_get_hobject(ctx, -2);
		DUK_ASSERT(fallback != NULL);
		DUK_HOBJECT_SET_PROTOTYPE_UPDREF(thr, fallback, proto);
	}
	duk_pop(ctx);

	/* [... constructor arg1 ... argN final_cons fallback] */

	/*
	 *  Manipulate callstack for the call.
	 */

	duk_dup_top(ctx);
	duk_insert(ctx, idx_cons + 1);  /* use fallback as 'this' value */
	duk_insert(ctx, idx_cons);      /* also stash it before constructor,
	                                 * in case we need it (as the fallback value)
	                                 */
	duk_pop(ctx);                   /* pop final_cons */


	/* [... fallback constructor fallback(this) arg1 ... argN];
	 * Note: idx_cons points to first 'fallback', not 'constructor'.
	 */

	DUK_DDD(DUK_DDDPRINT("before call, idx_cons+1 (constructor) -> %!T, idx_cons+2 (fallback/this) -> %!T, "
	                     "nargs=%ld, top=%ld",
	                     (duk_tval *) duk_get_tval(ctx, idx_cons + 1),
	                     (duk_tval *) duk_get_tval(ctx, idx_cons + 2),
	                     (long) nargs,
	                     (long) duk_get_top(ctx)));

	/*
	 *  Call the constructor function (called in "constructor mode").
	 */

	call_flags = DUK_CALL_FLAG_CONSTRUCTOR_CALL;  /* not protected, respect reclimit, is a constructor call */

	duk_handle_call_unprotected(thr,           /* thread */
	                            nargs,         /* num_stack_args */
	                            call_flags);   /* call_flags */

	/* [... fallback retval] */

	DUK_DDD(DUK_DDDPRINT("constructor call finished, fallback=%!iT, retval=%!iT",
	                     (duk_tval *) duk_get_tval(ctx, -2),
	                     (duk_tval *) duk_get_tval(ctx, -1)));

	/*
	 *  Determine whether to use the constructor return value as the created
	 *  object instance or not.
	 */

	if (duk_check_type_mask(ctx, -1, DUK_TYPE_MASK_OBJECT |
	                                 DUK_TYPE_MASK_BUFFER |
	                                 DUK_TYPE_MASK_LIGHTFUNC)) {
		duk_remove_m2(ctx);
	} else {
		duk_pop(ctx);
	}

	/*
	 *  Augment created errors upon creation (not when they are thrown or
	 *  rethrown).  __FILE__ and __LINE__ are not desirable here; the call
	 *  stack reflects the caller which is correct.
	 */

#if defined(DUK_USE_AUGMENT_ERROR_CREATE)
	duk_hthread_sync_currpc(thr);
	duk_err_augment_error_create(thr, thr, NULL, 0, 1 /*noblame_fileline*/);
#endif

	/* [... retval] */

	return;

 not_constructable:
#if defined(DUK_USE_VERBOSE_ERRORS)
#if defined(DUK_USE_PARANOID_ERRORS)
	DUK_ERROR_FMT1(thr, DUK_ERR_TYPE_ERROR, "%s not constructable", duk_get_type_name(ctx, -1));
#else
	DUK_ERROR_FMT1(thr, DUK_ERR_TYPE_ERROR, "%s not constructable", duk_push_string_readable(ctx, -1));
#endif
#else
	DUK_ERROR_TYPE(thr, "not constructable");
#endif
}
コード例 #7
0
ファイル: duk_js_ops.c プロジェクト: bihai/duk4vb
DUK_INTERNAL duk_bool_t duk_js_instanceof(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y) {
	duk_context *ctx = (duk_context *) thr;
	duk_hobject *func;
	duk_hobject *val;
	duk_hobject *proto;
	duk_uint_t sanity;

	/*
	 *  Get the values onto the stack first.  It would be possible to cover
	 *  some normal cases without resorting to the value stack.
	 *
	 *  The right hand side could be a light function (as they generally
	 *  behave like objects).  Light functions never have a 'prototype'
	 *  property so E5.1 Section 15.3.5.3 step 3 always throws a TypeError.
	 *  Using duk_require_hobject() is thus correct (except for error msg).
	 */

	duk_push_tval(ctx, tv_x);
	duk_push_tval(ctx, tv_y);
	func = duk_require_hobject(ctx, -1);

	/*
	 *  For bound objects, [[HasInstance]] just calls the target function
	 *  [[HasInstance]].  If that is again a bound object, repeat until
	 *  we find a non-bound Function object.
	 */

	/* XXX: this bound function resolution also happens elsewhere,
	 * move into a shared helper.
	 */

	sanity = DUK_HOBJECT_BOUND_CHAIN_SANITY;
	do {
		/* check func supports [[HasInstance]] (this is checked for every function
		 * in the bound chain, including the final one)
		 */

		if (!DUK_HOBJECT_IS_CALLABLE(func)) {
			/*
			 *  Note: of native Ecmascript objects, only Function instances
			 *  have a [[HasInstance]] internal property.  Custom objects might
			 *  also have it, but not in current implementation.
			 *
			 *  XXX: add a separate flag, DUK_HOBJECT_FLAG_ALLOW_INSTANCEOF?
			 */
			DUK_ERROR(thr, DUK_ERR_TYPE_ERROR, "invalid instanceof rval");
		}

		if (!DUK_HOBJECT_HAS_BOUND(func)) {
			break;
		}

		/* [ ... lval rval ] */

		duk_get_prop_stridx(ctx, -1, DUK_STRIDX_INT_TARGET);         /* -> [ ... lval rval new_rval ] */
		duk_replace(ctx, -1);                                        /* -> [ ... lval new_rval ] */
		func = duk_require_hobject(ctx, -1);

		/* func support for [[HasInstance]] checked in the beginning of the loop */
	} while (--sanity > 0);

	if (sanity == 0) {
		DUK_ERROR(thr, DUK_ERR_INTERNAL_ERROR, DUK_STR_BOUND_CHAIN_LIMIT);
	}

	/*
	 *  'func' is now a non-bound object which supports [[HasInstance]]
	 *  (which here just means DUK_HOBJECT_FLAG_CALLABLE).  Move on
	 *  to execute E5 Section 15.3.5.3.
	 */

	DUK_ASSERT(!DUK_HOBJECT_HAS_BOUND(func));
	DUK_ASSERT(DUK_HOBJECT_IS_CALLABLE(func));

	/* [ ... lval rval(func) ] */

	/* Handle lightfuncs through object coercion for now. */
	/* XXX: direct implementation */
	val = duk_get_hobject_or_lfunc_coerce(ctx, -2);
	if (!val) {
		goto pop_and_false;
	}

	duk_get_prop_stridx(ctx, -1, DUK_STRIDX_PROTOTYPE);  /* -> [ ... lval rval rval.prototype ] */
	proto = duk_require_hobject(ctx, -1);
	duk_pop(ctx);  /* -> [ ... lval rval ] */

	sanity = DUK_HOBJECT_PROTOTYPE_CHAIN_SANITY;
	do {
		/*
		 *  Note: prototype chain is followed BEFORE first comparison.  This
		 *  means that the instanceof lval is never itself compared to the
		 *  rval.prototype property.  This is apparently intentional, see E5
		 *  Section 15.3.5.3, step 4.a.
		 *
		 *  Also note:
		 *
		 *      js> (function() {}) instanceof Function
		 *      true
		 *      js> Function instanceof Function
		 *      true
		 *
		 *  For the latter, h_proto will be Function.prototype, which is the
		 *  built-in Function prototype.  Because Function.[[Prototype]] is
		 *  also the built-in Function prototype, the result is true.
		 */

		val = DUK_HOBJECT_GET_PROTOTYPE(thr->heap, val);

		if (!val) {
			goto pop_and_false;
		} else if (val == proto) {
			goto pop_and_true;
		}

		/* follow prototype chain */
	} while (--sanity > 0);

	if (sanity == 0) {
		DUK_ERROR(thr, DUK_ERR_INTERNAL_ERROR, DUK_STR_PROTOTYPE_CHAIN_LIMIT);
	}
	DUK_UNREACHABLE();

 pop_and_false:
	duk_pop_2(ctx);
	return 0;

 pop_and_true:
	duk_pop_2(ctx);
	return 1;
}