DUK_LOCAL void duk__run_object_finalizers(duk_heap *heap, duk_small_uint_t flags) {
duk_heaphdr *curr;
duk_heaphdr *next;
#if defined(DUK_USE_DEBUG)
duk_size_t count = 0;
#endif
duk_hthread *thr;
DUK_DD(DUK_DDPRINT("duk__run_object_finalizers: %p", (void *) heap));
thr = duk__get_temp_hthread(heap);
DUK_ASSERT(thr != NULL);
curr = heap->finalize_list;
while (curr) {
DUK_DDD(DUK_DDDPRINT("mark-and-sweep finalize: %p", (void *) curr));
DUK_ASSERT(DUK_HEAPHDR_GET_TYPE(curr) == DUK_HTYPE_OBJECT); /* only objects have finalizers */
DUK_ASSERT(!DUK_HEAPHDR_HAS_REACHABLE(curr)); /* flags have been already cleared */
DUK_ASSERT(!DUK_HEAPHDR_HAS_TEMPROOT(curr));
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(curr));
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(curr));
DUK_ASSERT(!DUK_HEAPHDR_HAS_READONLY(curr)); /* No finalizers for ROM objects */
if (DUK_LIKELY((flags & DUK_MS_FLAG_SKIP_FINALIZERS) == 0)) {
/* Run the finalizer, duk_hobject_run_finalizer() sets FINALIZED.
* Next mark-and-sweep will collect the object unless it has
* become reachable (i.e. rescued). FINALIZED prevents the
* finalizer from being executed again before that.
*/
duk_hobject_run_finalizer(thr, (duk_hobject *) curr); /* must never longjmp */
DUK_ASSERT(DUK_HEAPHDR_HAS_FINALIZED(curr));
} else {
/* Used during heap destruction: don't actually run finalizers
* because we're heading into forced finalization. Instead,
* queue finalizable objects back to the heap_allocated list.
*/
DUK_D(DUK_DPRINT("skip finalizers flag set, queue object to heap_allocated without finalizing"));
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(curr));
}
/* queue back to heap_allocated */
next = DUK_HEAPHDR_GET_NEXT(heap, curr);
DUK_HEAP_INSERT_INTO_HEAP_ALLOCATED(heap, curr);
curr = next;
#if defined(DUK_USE_DEBUG)
count++;
#endif
}
/* finalize_list will always be processed completely */
heap->finalize_list = NULL;
#if defined(DUK_USE_DEBUG)
DUK_D(DUK_DPRINT("mark-and-sweep finalize objects: %ld finalizers called", (long) count));
#endif
}
DUK_INTERNAL void *duk_heap_mem_alloc_checked(duk_hthread *thr, duk_size_t size) {
void *res;
DUK_ASSERT(thr != NULL);
res = duk_heap_mem_alloc(thr->heap, size);
if (DUK_LIKELY(res != NULL || size == 0)) {
return res;
}
DUK_ERROR_ALLOC_FAILED(thr);
DUK_WO_NORETURN(return NULL;);
DUK_INTERNAL void *duk_heap_mem_alloc_zeroed(duk_heap *heap, duk_size_t size) {
void *res;
DUK_ASSERT(heap != NULL);
DUK_ASSERT_DISABLE(size >= 0);
res = DUK_ALLOC(heap, size);
if (DUK_LIKELY(res != NULL)) {
duk_memzero(res, size);
}
return res;
}
DUK_INTERNAL void *duk_heap_mem_alloc_zeroed(duk_heap *heap, duk_size_t size) {
void *res;
DUK_ASSERT(heap != NULL);
DUK_ASSERT_DISABLE(size >= 0);
res = DUK_ALLOC(heap, size);
if (DUK_LIKELY(res != NULL)) {
/* assume memset with zero size is OK */
DUK_MEMZERO(res, size);
}
return res;
}
void duk_hobject_enumerator_create(duk_context *ctx, duk_small_uint_t enum_flags) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *enum_target;
duk_hobject *curr;
duk_hobject *res;
#if defined(DUK_USE_ES6_PROXY)
duk_hobject *h_proxy_target;
duk_hobject *h_proxy_handler;
duk_hobject *h_trap_result;
#endif
duk_uint_fast32_t i, len; /* used for array, stack, and entry indices */
DUK_ASSERT(ctx != NULL);
DUK_DDD(DUK_DDDPRINT("create enumerator, stack top: %ld", (long) duk_get_top(ctx)));
enum_target = duk_require_hobject(ctx, -1);
DUK_ASSERT(enum_target != NULL);
duk_push_object_internal(ctx);
res = duk_require_hobject(ctx, -1);
DUK_DDD(DUK_DDDPRINT("created internal object"));
/* [enum_target res] */
/* Target must be stored so that we can recheck whether or not
* keys still exist when we enumerate. This is not done if the
* enumeration result comes from a proxy trap as there is no
* real object to check against.
*/
duk_push_hobject(ctx, enum_target);
duk_put_prop_stridx(ctx, -2, DUK_STRIDX_INT_TARGET);
/* Initialize index so that we skip internal control keys. */
duk_push_int(ctx, DUK__ENUM_START_INDEX);
duk_put_prop_stridx(ctx, -2, DUK_STRIDX_INT_NEXT);
/*
* Proxy object handling
*/
#if defined(DUK_USE_ES6_PROXY)
if (DUK_LIKELY((enum_flags & DUK_ENUM_NO_PROXY_BEHAVIOR) != 0)) {
goto skip_proxy;
}
if (DUK_LIKELY(!duk_hobject_proxy_check(thr,
enum_target,
&h_proxy_target,
&h_proxy_handler))) {
goto skip_proxy;
}
DUK_DDD(DUK_DDDPRINT("proxy enumeration"));
duk_push_hobject(ctx, h_proxy_handler);
if (!duk_get_prop_stridx(ctx, -1, DUK_STRIDX_ENUMERATE)) {
/* No need to replace the 'enum_target' value in stack, only the
* enum_target reference. This also ensures that the original
* enum target is reachable, which keeps the proxy and the proxy
* target reachable. We do need to replace the internal _target.
*/
DUK_DDD(DUK_DDDPRINT("no enumerate trap, enumerate proxy target instead"));
DUK_DDD(DUK_DDDPRINT("h_proxy_target=%!O", (duk_heaphdr *) h_proxy_target));
enum_target = h_proxy_target;
duk_push_hobject(ctx, enum_target); /* -> [ ... enum_target res handler undefined target ] */
duk_put_prop_stridx(ctx, -4, DUK_STRIDX_INT_TARGET);
duk_pop_2(ctx); /* -> [ ... enum_target res ] */
goto skip_proxy;
}
/* [ ... enum_target res handler trap ] */
duk_insert(ctx, -2);
duk_push_hobject(ctx, h_proxy_target); /* -> [ ... enum_target res trap handler target ] */
duk_call_method(ctx, 1 /*nargs*/); /* -> [ ... enum_target res trap_result ] */
h_trap_result = duk_require_hobject(ctx, -1);
DUK_UNREF(h_trap_result);
/* Copy trap result keys into the enumerator object. */
len = (duk_uint_fast32_t) duk_get_length(ctx, -1);
for (i = 0; i < len; i++) {
/* XXX: not sure what the correct semantic details are here,
* e.g. handling of missing values (gaps), handling of non-array
* trap results, etc.
*
* For keys, we simply skip non-string keys which seems to be
* consistent with how e.g. Object.keys() will process proxy trap
* results (ES6 draft, Section 19.1.2.14).
*/
if (duk_get_prop_index(ctx, -1, i) && duk_is_string(ctx, -1)) {
/* [ ... enum_target res trap_result val ] */
duk_push_true(ctx);
/* [ ... enum_target res trap_result val true ] */
duk_put_prop(ctx, -4);
} else {
duk_pop(ctx);
}
}
/* [ ... enum_target res trap_result ] */
duk_pop(ctx);
duk_remove(ctx, -2);
/* [ ... res ] */
/* The internal _target property is kept pointing to the original
* enumeration target (the proxy object), so that the enumerator
* 'next' operation can read property values if so requested. The
* fact that the _target is a proxy disables key existence check
* during enumeration.
*/
DUK_DDD(DUK_DDDPRINT("proxy enumeration, final res: %!O", (duk_heaphdr *) res));
goto compact_and_return;
skip_proxy:
#endif /* DUK_USE_ES6_PROXY */
curr = enum_target;
while (curr) {
/*
* Virtual properties.
*
* String and buffer indices are virtual and always enumerable,
* 'length' is virtual and non-enumerable. Array and arguments
* object props have special behavior but are concrete.
*/
if (DUK_HOBJECT_HAS_EXOTIC_STRINGOBJ(curr) ||
DUK_HOBJECT_HAS_EXOTIC_BUFFEROBJ(curr)) {
/* String and buffer enumeration behavior is identical now,
* so use shared handler.
*/
if (DUK_HOBJECT_HAS_EXOTIC_STRINGOBJ(curr)) {
duk_hstring *h_val;
h_val = duk_hobject_get_internal_value_string(thr->heap, curr);
DUK_ASSERT(h_val != NULL); /* string objects must not created without internal value */
len = (duk_uint_fast32_t) DUK_HSTRING_GET_CHARLEN(h_val);
} else {
duk_hbuffer *h_val;
DUK_ASSERT(DUK_HOBJECT_HAS_EXOTIC_BUFFEROBJ(curr));
h_val = duk_hobject_get_internal_value_buffer(thr->heap, curr);
DUK_ASSERT(h_val != NULL); /* buffer objects must not created without internal value */
len = (duk_uint_fast32_t) DUK_HBUFFER_GET_SIZE(h_val);
}
for (i = 0; i < len; i++) {
duk_hstring *k;
k = duk_heap_string_intern_u32_checked(thr, i);
DUK_ASSERT(k);
duk_push_hstring(ctx, k);
duk_push_true(ctx);
/* [enum_target res key true] */
duk_put_prop(ctx, -3);
/* [enum_target res] */
}
/* 'length' property is not enumerable, but is included if
* non-enumerable properties are requested.
*/
if (enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE) {
duk_push_hstring_stridx(ctx, DUK_STRIDX_LENGTH);
duk_push_true(ctx);
duk_put_prop(ctx, -3);
}
} else if (DUK_HOBJECT_HAS_EXOTIC_DUKFUNC(curr)) {
if (enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE) {
duk_push_hstring_stridx(ctx, DUK_STRIDX_LENGTH);
duk_push_true(ctx);
duk_put_prop(ctx, -3);
}
}
/*
* Array part
*
* Note: ordering between array and entry part must match 'abandon array'
* behavior in duk_hobject_props.c: key order after an array is abandoned
* must be the same.
*/
for (i = 0; i < (duk_uint_fast32_t) curr->a_size; i++) {
duk_hstring *k;
duk_tval *tv;
tv = DUK_HOBJECT_A_GET_VALUE_PTR(curr, i);
if (DUK_TVAL_IS_UNDEFINED_UNUSED(tv)) {
continue;
}
k = duk_heap_string_intern_u32_checked(thr, i);
DUK_ASSERT(k);
duk_push_hstring(ctx, k);
duk_push_true(ctx);
/* [enum_target res key true] */
duk_put_prop(ctx, -3);
/* [enum_target res] */
}
/*
* Entries part
*/
for (i = 0; i < (duk_uint_fast32_t) curr->e_next; i++) {
duk_hstring *k;
k = DUK_HOBJECT_E_GET_KEY(curr, i);
if (!k) {
continue;
}
if (!DUK_HOBJECT_E_SLOT_IS_ENUMERABLE(curr, i) &&
!(enum_flags & DUK_ENUM_INCLUDE_NONENUMERABLE)) {
continue;
}
if (DUK_HSTRING_HAS_INTERNAL(k) &&
!(enum_flags & DUK_ENUM_INCLUDE_INTERNAL)) {
continue;
}
if ((enum_flags & DUK_ENUM_ARRAY_INDICES_ONLY) &&
(DUK_HSTRING_GET_ARRIDX_SLOW(k) == DUK_HSTRING_NO_ARRAY_INDEX)) {
continue;
}
DUK_ASSERT(DUK_HOBJECT_E_SLOT_IS_ACCESSOR(curr, i) ||
!DUK_TVAL_IS_UNDEFINED_UNUSED(&DUK_HOBJECT_E_GET_VALUE_PTR(curr, i)->v));
duk_push_hstring(ctx, k);
duk_push_true(ctx);
/* [enum_target res key true] */
duk_put_prop(ctx, -3);
/* [enum_target res] */
}
if (enum_flags & DUK_ENUM_OWN_PROPERTIES_ONLY) {
break;
}
curr = curr->prototype;
}
/* [enum_target res] */
duk_remove(ctx, -2);
/* [res] */
if ((enum_flags & (DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) ==
(DUK_ENUM_ARRAY_INDICES_ONLY | DUK_ENUM_SORT_ARRAY_INDICES)) {
/*
* Some E5/E5.1 algorithms require that array indices are iterated
* in a strictly ascending order. This is the case for e.g.
* Array.prototype.forEach() and JSON.stringify() PropertyList
* handling.
*
* To ensure this property for arrays with an array part (and
* arbitrary objects too, since e.g. forEach() can be applied
* to an array), the caller can request that we sort the keys
* here.
*/
/* XXX: avoid this at least when enum_target is an Array, it has an
* array part, and no ancestor properties were included? Not worth
* it for JSON, but maybe worth it for forEach().
*/
/* XXX: may need a 'length' filter for forEach()
*/
DUK_DDD(DUK_DDDPRINT("sort array indices by caller request"));
duk__sort_array_indices(res);
}
#if defined(DUK_USE_ES6_PROXY)
compact_and_return:
#endif
/* compact; no need to seal because object is internal */
duk_hobject_compact_props(thr, res);
DUK_DDD(DUK_DDDPRINT("created enumerator object: %!iT", (duk_tval *) duk_get_tval(ctx, -1)));
}
DUK_INTERNAL void *duk_heap_mem_alloc(duk_heap *heap, duk_size_t size) {
void *res;
duk_small_int_t i;
DUK_ASSERT(heap != NULL);
DUK_ASSERT_DISABLE(size >= 0);
/*
* Voluntary periodic GC (if enabled)
*/
DUK__VOLUNTARY_PERIODIC_GC(heap);
/*
* First attempt
*/
#if defined(DUK_USE_GC_TORTURE)
/* Simulate alloc failure on every alloc, except when mark-and-sweep
* is running.
*/
if (heap->ms_prevent_count == 0) {
DUK_DDD(DUK_DDDPRINT("gc torture enabled, pretend that first alloc attempt fails"));
res = NULL;
DUK_UNREF(res);
goto skip_attempt;
}
#endif
res = heap->alloc_func(heap->heap_udata, size);
if (DUK_LIKELY(res || size == 0)) {
/* For zero size allocations NULL is allowed. */
return res;
}
#if defined(DUK_USE_GC_TORTURE)
skip_attempt:
#endif
DUK_D(DUK_DPRINT("first alloc attempt failed, attempt to gc and retry"));
#if 0
/*
* Avoid a GC if GC is already running. This can happen at a late
* stage in a GC when we try to e.g. resize the stringtable
* or compact objects.
*
* NOTE: explicit handling isn't actually be needed: if the GC is
* not allowed, duk_heap_mark_and_sweep() will reject it for every
* attempt in the loop below, resulting in a NULL same as here.
*/
if (heap->ms_prevent_count != 0) {
DUK_D(DUK_DPRINT("duk_heap_mem_alloc() failed, gc in progress (gc skipped), alloc size %ld", (long) size));
return NULL;
}
#endif
/*
* Retry with several GC attempts. Initial attempts are made without
* emergency mode; later attempts use emergency mode which minimizes
* memory allocations forcibly.
*/
for (i = 0; i < DUK_HEAP_ALLOC_FAIL_MARKANDSWEEP_LIMIT; i++) {
duk_small_uint_t flags;
flags = 0;
if (i >= DUK_HEAP_ALLOC_FAIL_MARKANDSWEEP_EMERGENCY_LIMIT - 1) {
flags |= DUK_MS_FLAG_EMERGENCY;
}
duk_heap_mark_and_sweep(heap, flags);
res = heap->alloc_func(heap->heap_udata, size);
if (res) {
DUK_D(DUK_DPRINT("duk_heap_mem_alloc() succeeded after gc (pass %ld), alloc size %ld",
(long) (i + 1), (long) size));
return res;
}
}
DUK_D(DUK_DPRINT("duk_heap_mem_alloc() failed even after gc, alloc size %ld", (long) size));
return NULL;
}
/* Shared helper for Object.getOwnPropertyNames() and Object.keys().
* Magic: 0=getOwnPropertyNames, 1=Object.keys.
*/
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_keys_shared(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *obj;
#if defined(DUK_USE_ES6_PROXY)
duk_hobject *h_proxy_target;
duk_hobject *h_proxy_handler;
duk_hobject *h_trap_result;
duk_uarridx_t i, len, idx;
#endif
duk_small_uint_t enum_flags;
DUK_ASSERT_TOP(ctx, 1);
obj = duk_require_hobject_or_lfunc_coerce(ctx, 0);
DUK_ASSERT(obj != NULL);
DUK_UNREF(obj);
#if defined(DUK_USE_ES6_PROXY)
if (DUK_LIKELY(!duk_hobject_proxy_check(thr,
obj,
&h_proxy_target,
&h_proxy_handler))) {
goto skip_proxy;
}
duk_push_hobject(ctx, h_proxy_handler);
if (!duk_get_prop_stridx(ctx, -1, DUK_STRIDX_OWN_KEYS)) {
/* Careful with reachability here: don't pop 'obj' before pushing
* proxy target.
*/
DUK_DDD(DUK_DDDPRINT("no ownKeys trap, get keys of target instead"));
duk_pop_2(ctx);
duk_push_hobject(ctx, h_proxy_target);
duk_replace(ctx, 0);
DUK_ASSERT_TOP(ctx, 1);
goto skip_proxy;
}
/* [ obj handler trap ] */
duk_insert(ctx, -2);
duk_push_hobject(ctx, h_proxy_target); /* -> [ obj trap handler target ] */
duk_call_method(ctx, 1 /*nargs*/); /* -> [ obj trap_result ] */
h_trap_result = duk_require_hobject(ctx, -1);
DUK_UNREF(h_trap_result);
len = (duk_uarridx_t) duk_get_length(ctx, -1);
idx = 0;
duk_push_array(ctx);
for (i = 0; i < len; i++) {
/* [ obj trap_result res_arr ] */
if (duk_get_prop_index(ctx, -2, i) && duk_is_string(ctx, -1)) {
/* XXX: for Object.keys() we should check enumerability of key */
/* [ obj trap_result res_arr propname ] */
duk_put_prop_index(ctx, -2, idx);
idx++;
} else {
duk_pop(ctx);
}
}
/* XXX: for Object.keys() the [[OwnPropertyKeys]] result (trap result)
* should be filtered so that only enumerable keys remain. Enumerability
* should be checked with [[GetOwnProperty]] on the original object
* (i.e., the proxy in this case). If the proxy has a getOwnPropertyDescriptor
* trap, it should be triggered for every property. If the proxy doesn't have
* the trap, enumerability should be checked against the target object instead.
* We don't do any of this now, so Object.keys() and Object.getOwnPropertyNames()
* return the same result now for proxy traps. We still do clean up the trap
* result, so that Object.keys() and Object.getOwnPropertyNames() will return a
* clean array of strings without gaps.
*/
return 1;
skip_proxy:
#endif /* DUK_USE_ES6_PROXY */
DUK_ASSERT_TOP(ctx, 1);
if (duk_get_current_magic(ctx)) {
/* Object.keys */
enum_flags = DUK_ENUM_OWN_PROPERTIES_ONLY |
DUK_ENUM_NO_PROXY_BEHAVIOR;
} else {
/* Object.getOwnPropertyNames */
enum_flags = DUK_ENUM_INCLUDE_NONENUMERABLE |
DUK_ENUM_OWN_PROPERTIES_ONLY |
DUK_ENUM_NO_PROXY_BEHAVIOR;
}
return duk_hobject_get_enumerated_keys(ctx, enum_flags);
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_keys_shared(duk_hthread *thr) {
duk_hobject *obj;
#if defined(DUK_USE_ES6_PROXY)
duk_hobject *h_proxy_target;
duk_hobject *h_proxy_handler;
duk_hobject *h_trap_result;
#endif
duk_small_uint_t enum_flags;
duk_int_t magic;
DUK_ASSERT_TOP(thr, 1);
magic = duk_get_current_magic(thr);
if (magic == 3) {
/* ES2015 Section 26.1.11 requires a TypeError for non-objects. Lightfuncs
* and plain buffers pretend to be objects, so accept those too.
*/
obj = duk_require_hobject_promote_mask(thr, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
} else {
/* ES2015: ToObject coerce. */
obj = duk_to_hobject(thr, 0);
}
DUK_ASSERT(obj != NULL);
DUK_UNREF(obj);
/* XXX: proxy chains */
#if defined(DUK_USE_ES6_PROXY)
/* XXX: better sharing of code between proxy target call sites */
if (DUK_LIKELY(!duk_hobject_proxy_check(obj,
&h_proxy_target,
&h_proxy_handler))) {
goto skip_proxy;
}
duk_push_hobject(thr, h_proxy_handler);
if (!duk_get_prop_stridx_short(thr, -1, DUK_STRIDX_OWN_KEYS)) {
/* Careful with reachability here: don't pop 'obj' before pushing
* proxy target.
*/
DUK_DDD(DUK_DDDPRINT("no ownKeys trap, get keys of target instead"));
duk_pop_2(thr);
duk_push_hobject(thr, h_proxy_target);
duk_replace(thr, 0);
DUK_ASSERT_TOP(thr, 1);
goto skip_proxy;
}
/* [ obj handler trap ] */
duk_insert(thr, -2);
duk_push_hobject(thr, h_proxy_target); /* -> [ obj trap handler target ] */
duk_call_method(thr, 1 /*nargs*/); /* -> [ obj trap_result ] */
h_trap_result = duk_require_hobject(thr, -1);
DUK_UNREF(h_trap_result);
magic = duk_get_current_magic(thr);
DUK_ASSERT(magic >= 0 && magic < (duk_int_t) (sizeof(duk__object_keys_enum_flags) / sizeof(duk_small_uint_t)));
enum_flags = duk__object_keys_enum_flags[magic];
duk_proxy_ownkeys_postprocess(thr, h_proxy_target, enum_flags);
return 1;
skip_proxy:
#endif /* DUK_USE_ES6_PROXY */
DUK_ASSERT_TOP(thr, 1);
magic = duk_get_current_magic(thr);
DUK_ASSERT(magic >= 0 && magic < (duk_int_t) (sizeof(duk__object_keys_enum_flags) / sizeof(duk_small_uint_t)));
enum_flags = duk__object_keys_enum_flags[magic];
return duk_hobject_get_enumerated_keys(thr, enum_flags);
}
