C++ DUK_DDD函数代码示例

static duk_hstring *duk__find_matching_string(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, duk_uint8_t *str, duk_uint32_t blen, duk_uint32_t strhash) {
	duk_uint32_t i;
	duk_uint32_t step;

	DUK_ASSERT(size > 0);

	i = DUK__HASH_INITIAL(strhash, size);
	step = DUK__HASH_PROBE_STEP(strhash);
	for (;;) {
		duk_hstring *e;

		e = entries[i];
		if (!e) {
			return NULL;
		}
		if (e != DUK__DELETED_MARKER(heap) && DUK_HSTRING_GET_BYTELEN(e) == blen) {
			if (DUK_MEMCMP(str, DUK_HSTRING_GET_DATA(e), blen) == 0) {
				DUK_DDD(DUK_DDDPRINT("find matching hit: %d (step %d, size %d)", i, step, size));
				return e;
			}
		}
		DUK_DDD(DUK_DDDPRINT("find matching miss: %d (step %d, size %d)", i, step, size));
		i = (i + step) % size;

		/* looping should never happen */
		DUK_ASSERT(i != DUK__HASH_INITIAL(strhash, size));
	}
	DUK_UNREACHABLE();
}

static void duk__remove_matching_hstring(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, duk_hstring *h) {
	duk_uint32_t i;
	duk_uint32_t step;

	DUK_ASSERT(size > 0);

	i = DUK__HASH_INITIAL(h->hash, size);
	step = DUK__HASH_PROBE_STEP(h->hash);
	for (;;) {
		duk_hstring *e;

		e = entries[i];
		if (!e) {
			DUK_UNREACHABLE();
			break;
		}
		if (e == h) {
			/* st_used remains the same, DELETED is counted as used */
			DUK_DDD(DUK_DDDPRINT("free matching hit: %d", i));
			entries[i] = DUK__DELETED_MARKER(heap);
			break;
		}

		DUK_DDD(DUK_DDDPRINT("free matching miss: %d", i));
		i = (i + step) % size;

		/* looping should never happen */
		DUK_ASSERT(i != DUK__HASH_INITIAL(h->hash, size));
	}
}

/* Prepare value stack for a method call through an object property.
 * May currently throw an error e.g. when getting the property.
 */
DUK_LOCAL void duk__call_prop_prep_stack(duk_context *ctx, duk_idx_t normalized_obj_idx, duk_idx_t nargs) {
	DUK_ASSERT_CTX_VALID(ctx);

	DUK_DDD(DUK_DDDPRINT("duk__call_prop_prep_stack, normalized_obj_idx=%ld, nargs=%ld, stacktop=%ld",
	                     (long) normalized_obj_idx, (long) nargs, (long) duk_get_top(ctx)));

	/* [... key arg1 ... argN] */

	/* duplicate key */
	duk_dup(ctx, -nargs - 1);  /* Note: -nargs alone would fail for nargs == 0, this is OK */
	duk_get_prop(ctx, normalized_obj_idx);

	DUK_DDD(DUK_DDDPRINT("func: %!T", (duk_tval *) duk_get_tval(ctx, -1)));

	/* [... key arg1 ... argN func] */

	duk_replace(ctx, -nargs - 2);

	/* [... func arg1 ... argN] */

	duk_dup(ctx, normalized_obj_idx);
	duk_insert(ctx, -nargs - 1);

	/* [... func this arg1 ... argN] */
}

DUK_INTERNAL duk_ucodepoint_t duk_hstring_char_code_at_raw(duk_hthread *thr, duk_hstring *h, duk_uint_t pos) {
	duk_uint32_t boff;
	const duk_uint8_t *p, *p_start, *p_end;
	duk_ucodepoint_t cp;

	/* Caller must check character offset to be inside the string. */
	DUK_ASSERT(thr != NULL);
	DUK_ASSERT(h != NULL);
	DUK_ASSERT_DISABLE(pos >= 0);  /* unsigned */
	DUK_ASSERT(pos < (duk_uint_t) DUK_HSTRING_GET_CHARLEN(h));

	boff = duk_heap_strcache_offset_char2byte(thr, h, (duk_uint32_t) pos);
	DUK_DDD(DUK_DDDPRINT("charCodeAt: pos=%ld -> boff=%ld, str=%!O",
	                     (long) pos, (long) boff, (duk_heaphdr *) h));
	DUK_ASSERT_DISABLE(boff >= 0);
	DUK_ASSERT(boff < DUK_HSTRING_GET_BYTELEN(h));

	p_start = DUK_HSTRING_GET_DATA(h);
	p_end = p_start + DUK_HSTRING_GET_BYTELEN(h);
	p = p_start + boff;
	DUK_DDD(DUK_DDDPRINT("p_start=%p, p_end=%p, p=%p",
	                     (void *) p_start, (void *) p_end, (void *) p));

	/* This may throw an error though not for valid E5 strings. */
	cp = duk_unicode_decode_xutf8_checked(thr, &p, p_start, p_end);
	return cp;
}

static void duk__insert_hstring(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, duk_uint32_t *p_used, duk_hstring *h) {
	duk_uint32_t i;
	duk_uint32_t step;

	DUK_ASSERT(size > 0);

	i = DUK__HASH_INITIAL(DUK_HSTRING_GET_HASH(h), size);
	step = DUK__HASH_PROBE_STEP(DUK_HSTRING_GET_HASH(h)); 
	for (;;) {
		duk_hstring *e;
		
		e = entries[i];
		if (e == NULL) {
			DUK_DDD(DUK_DDDPRINT("insert hit (null): %d", i));
			entries[i] = h;
			(*p_used)++;
			break;
		} else if (e == DUK__DELETED_MARKER(heap)) {
			/* st_used remains the same, DELETED is counted as used */
			DUK_DDD(DUK_DDDPRINT("insert hit (deleted): %d", i));
			entries[i] = h;
			break;
		}
		DUK_DDD(DUK_DDDPRINT("insert miss: %d", i));
		i = (i + step) % size;

		/* looping should never happen */
		DUK_ASSERT(i != DUK__HASH_INITIAL(DUK_HSTRING_GET_HASH(h), size));
	}
}

DUK_INTERNAL duk_bool_t duk_bi_date_parse_string_strptime(duk_context *ctx, const char *str) {
	struct tm tm;
	time_t t;
	char buf[DUK__STRPTIME_BUF_SIZE];

	/* copy to buffer with spare to avoid Valgrind gripes from strptime */
	DUK_ASSERT(str != NULL);
	DUK_MEMZERO(buf, sizeof(buf));  /* valgrind whine without this */
	DUK_SNPRINTF(buf, sizeof(buf), "%s", (const char *) str);
	buf[sizeof(buf) - 1] = (char) 0;

	DUK_DDD(DUK_DDDPRINT("parsing: '%s'", (const char *) buf));

	DUK_MEMZERO(&tm, sizeof(tm));
	if (strptime((const char *) buf, "%c", &tm) != NULL) {
		DUK_DDD(DUK_DDDPRINT("before mktime: tm={sec:%ld,min:%ld,hour:%ld,mday:%ld,mon:%ld,year:%ld,"
		                     "wday:%ld,yday:%ld,isdst:%ld}",
		                     (long) tm.tm_sec, (long) tm.tm_min, (long) tm.tm_hour,
		                     (long) tm.tm_mday, (long) tm.tm_mon, (long) tm.tm_year,
		                     (long) tm.tm_wday, (long) tm.tm_yday, (long) tm.tm_isdst));
		tm.tm_isdst = -1;  /* negative: dst info not available */

		t = mktime(&tm);
		DUK_DDD(DUK_DDDPRINT("mktime() -> %ld", (long) t));
		if (t >= 0) {
			duk_push_number(ctx, ((duk_double_t) t) * 1000.0);
			return 1;
		}
	}

	return 0;
}

DUK_LOCAL void duk__add_compiler_error_line(duk_hthread *thr) {
	duk_context *ctx;

	/* Append a "(line NNN)" to the "message" property of any error
	 * thrown during compilation.  Usually compilation errors are
	 * SyntaxErrors but they can also be out-of-memory errors and
	 * the like.
	 */

	/* [ ... error ] */

	ctx = (duk_context *) thr;
	DUK_ASSERT(duk_is_object(ctx, -1));

	if (!(thr->compile_ctx != NULL && thr->compile_ctx->h_filename != NULL)) {
		return;
	}

	DUK_DDD(DUK_DDDPRINT("compile error, before adding line info: %!T",
	                     (duk_tval *) duk_get_tval(ctx, -1)));

	if (duk_get_prop_stridx(ctx, -1, DUK_STRIDX_MESSAGE)) {
		duk_push_sprintf(ctx, " (line %ld)", (long) thr->compile_ctx->curr_token.start_line);
		duk_concat(ctx, 2);
		duk_put_prop_stridx(ctx, -2, DUK_STRIDX_MESSAGE);
	} else {
		duk_pop(ctx);
	}

	DUK_DDD(DUK_DDDPRINT("compile error, after adding line info: %!T",
	                     (duk_tval *) duk_get_tval(ctx, -1)));
}

DUK_INTERNAL duk_ret_t duk_bi_array_prototype_to_string(duk_context *ctx) {
	(void) duk_push_this_coercible_to_object(ctx);
	duk_get_prop_stridx(ctx, -1, DUK_STRIDX_JOIN);

	/* [ ... this func ] */
	if (!duk_is_callable(ctx, -1)) {
		/* Fall back to the initial (original) Object.toString().  We don't
		 * currently have pointers to the built-in functions, only the top
		 * level global objects (like "Array") so this is now done in a bit
		 * of a hacky manner.  It would be cleaner to push the (original)
		 * function and use duk_call_method().
		 */

		/* XXX: 'this' will be ToObject() coerced twice, which is incorrect
		 * but should have no visible side effects.
		 */
		DUK_DDD(DUK_DDDPRINT("this.join is not callable, fall back to (original) Object.toString"));
		duk_set_top(ctx, 0);
		return duk_bi_object_prototype_to_string(ctx);  /* has access to 'this' binding */
	}

	/* [ ... this func ] */

	duk_insert(ctx, -2);

	/* [ ... func this ] */

	DUK_DDD(DUK_DDDPRINT("calling: func=%!iT, this=%!iT",
	                     (duk_tval *) duk_get_tval(ctx, -2),
	                     (duk_tval *) duk_get_tval(ctx, -1)));
	duk_call_method(ctx, 0);

	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);
}

DUK_LOCAL duk_ret_t duk__finalize_helper(duk_context *ctx, void *udata) {
	duk_hthread *thr;

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

	DUK_DDD(DUK_DDDPRINT("protected finalization helper running"));

	/* [... obj] */

	/* XXX: Finalizer lookup should traverse the prototype chain (to allow
	 * inherited finalizers) but should not invoke accessors or proxy object
	 * behavior.  At the moment this lookup will invoke proxy behavior, so
	 * caller must ensure that this function is not called if the target is
	 * a Proxy.
	 */

	duk_get_prop_stridx_short(ctx, -1, DUK_STRIDX_INT_FINALIZER);  /* -> [... obj finalizer] */
	if (!duk_is_callable(ctx, -1)) {
		DUK_DDD(DUK_DDDPRINT("-> no finalizer or finalizer not callable"));
		return 0;
	}
	duk_dup_m2(ctx);
	duk_push_boolean(ctx, DUK_HEAP_HAS_FINALIZER_NORESCUE(thr->heap));
	DUK_DDD(DUK_DDDPRINT("-> finalizer found, calling finalizer"));
	duk_call(ctx, 2);  /* [ ... obj finalizer obj heapDestruct ]  -> [ ... obj retval ] */
	DUK_DDD(DUK_DDDPRINT("finalizer finished successfully"));
	return 0;

	/* Note: we rely on duk_safe_call() to fix up the stack for the caller,
	 * so we don't need to pop stuff here.  There is no return value;
	 * caller determines rescued status based on object refcount.
	 */
}

DUK_INTERNAL void duk_hobject_run_finalizer(duk_hthread *thr, duk_hobject *obj) {
	duk_context *ctx = (duk_context *) thr;
	duk_ret_t rc;
#if defined(DUK_USE_ASSERTIONS)
	duk_idx_t entry_top;
#endif

	DUK_DDD(DUK_DDDPRINT("running object finalizer for object: %p", (void *) obj));

	DUK_ASSERT(thr != NULL);
	DUK_ASSERT(ctx != NULL);
	DUK_ASSERT(obj != NULL);
	DUK_ASSERT_VALSTACK_SPACE(thr, 1);

#if defined(DUK_USE_ASSERTIONS)
	entry_top = duk_get_top(ctx);
#endif
	/*
	 *  Get and call the finalizer.  All of this must be wrapped
	 *  in a protected call, because even getting the finalizer
	 *  may trigger an error (getter may throw one, for instance).
	 */

	DUK_ASSERT(!DUK_HEAPHDR_HAS_READONLY((duk_heaphdr *) obj));
	if (DUK_HEAPHDR_HAS_FINALIZED((duk_heaphdr *) obj)) {
		DUK_D(DUK_DPRINT("object already finalized, avoid running finalizer twice: %!O", obj));
		return;
	}
	DUK_HEAPHDR_SET_FINALIZED((duk_heaphdr *) obj);  /* ensure never re-entered until rescue cycle complete */
	if (DUK_HOBJECT_HAS_EXOTIC_PROXYOBJ(obj)) {
		/* This shouldn't happen; call sites should avoid looking up
		 * _Finalizer "through" a Proxy, but ignore if we come here
		 * with a Proxy to avoid finalizer re-entry.
		 */
		DUK_D(DUK_DPRINT("object is a proxy, skip finalizer call"));
		return;
	}

	/* XXX: use a NULL error handler for the finalizer call? */

	DUK_DDD(DUK_DDDPRINT("-> finalizer found, calling wrapped finalize helper"));
	duk_push_hobject(ctx, obj);  /* this also increases refcount by one */
	rc = duk_safe_call(ctx, duk__finalize_helper, NULL /*udata*/, 0 /*nargs*/, 1 /*nrets*/);  /* -> [... obj retval/error] */
	DUK_ASSERT_TOP(ctx, entry_top + 2);  /* duk_safe_call discipline */

	if (rc != DUK_EXEC_SUCCESS) {
		/* Note: we ask for one return value from duk_safe_call to get this
		 * error debugging here.
		 */
		DUK_D(DUK_DPRINT("wrapped finalizer call failed for object %p (ignored); error: %!T",
		                 (void *) obj, (duk_tval *) duk_get_tval(ctx, -1)));
	}
	duk_pop_2(ctx);  /* -> [...] */

	DUK_ASSERT_TOP(ctx, entry_top);
}

DUK_INTERNAL void duk_err_augment_error_create(duk_hthread *thr, duk_hthread *thr_callstack, const char *c_filename, duk_int_t c_line, duk_bool_t noblame_fileline) {
	duk_context *ctx = (duk_context *) thr;
	duk_hobject *obj;

	DUK_ASSERT(thr != NULL);
	DUK_ASSERT(thr_callstack != NULL);
	DUK_ASSERT(ctx != NULL);

	/* [ ... error ] */

	/*
	 *  Criteria for augmenting:
	 *
	 *   - augmentation enabled in build (naturally)
	 *   - error value internal prototype chain contains the built-in
	 *     Error prototype object (i.e. 'val instanceof Error')
	 *
	 *  Additional criteria for built-in augmenting:
	 *
	 *   - error value is an extensible object
	 */

	obj = duk_get_hobject(ctx, -1);
	if (!obj) {
		DUK_DDD(DUK_DDDPRINT("value is not an object, skip both built-in and user augment"));
		return;
	}
	if (!duk_hobject_prototype_chain_contains(thr, obj, thr->builtins[DUK_BIDX_ERROR_PROTOTYPE], 1 /*ignore_loop*/)) {
		/* If the value has a prototype loop, it's critical not to
		 * throw here.  Instead, assume the value is not to be
		 * augmented.
		 */
		DUK_DDD(DUK_DDDPRINT("value is not an error instance, skip both built-in and user augment"));
		return;
	}
	if (DUK_HOBJECT_HAS_EXTENSIBLE(obj)) {
		DUK_DDD(DUK_DDDPRINT("error meets criteria, built-in augment"));
		duk__err_augment_builtin_create(thr, thr_callstack, c_filename, c_line, noblame_fileline, obj);
	} else {
		DUK_DDD(DUK_DDDPRINT("error does not meet criteria, no built-in augment"));
	}

	/* [ ... error ] */

#if defined(DUK_USE_ERRCREATE)
	duk__err_augment_user(thr, DUK_STRIDX_ERR_CREATE);
#endif
}

/* Debug print which visualizes the qsort partitioning process. */
DUK_LOCAL void duk__debuglog_qsort_state(duk_context *ctx, duk_int_t lo, duk_int_t hi, duk_int_t pivot) {
	char buf[4096];
	char *ptr = buf;
	duk_int_t i, n;
	n = (duk_int_t) duk_get_length(ctx, 1);
	if (n > 4000) {
		n = 4000;
	}
	*ptr++ = '[';
	for (i = 0; i < n; i++) {
		if (i == pivot) {
			*ptr++ = '|';
		} else if (i == lo) {
			*ptr++ = '<';
		} else if (i == hi) {
			*ptr++ = '>';
		} else if (i >= lo && i <= hi) {
			*ptr++ = '-';
		} else {
			*ptr++ = ' ';
		}
	}
	*ptr++ = ']';
	*ptr++ = '\0';

	DUK_DDD(DUK_DDDPRINT("%s   (lo=%ld, hi=%ld, pivot=%ld)",
	                     (const char *) buf, (long) lo, (long) hi, (long) pivot));
}

DUK_INTERNAL duk_ret_t duk_bi_function_prototype_call(duk_context *ctx) {
	duk_idx_t nargs;

	/* Step 1 is not necessary because duk_call_method() will take
	 * care of it.
	 */

	/* vararg function, thisArg needs special handling */
	nargs = duk_get_top(ctx);  /* = 1 + arg count */
	if (nargs == 0) {
		duk_push_undefined(ctx);
		nargs++;
	}
	DUK_ASSERT(nargs >= 1);

	/* [ thisArg arg1 ... argN ] */

	duk_push_this(ctx);  /* 'func' in the algorithm */
	duk_insert(ctx, 0);

	/* [ func thisArg arg1 ... argN ] */

	DUK_DDD(DUK_DDDPRINT("func=%!iT, thisArg=%!iT, argcount=%ld, top=%ld",
	                     (duk_tval *) duk_get_tval(ctx, 0),
	                     (duk_tval *) duk_get_tval(ctx, 1),
	                     (long) (nargs - 1),
	                     (long) duk_get_top(ctx)));
	duk_call_method(ctx, nargs - 1);
	return 1;
}

/* Debug print which visualizes the qsort partitioning process. */
static void duk__debuglog_qsort_state(duk_context *ctx, int lo, int hi, int pivot) {
	char buf[4096];
	char *ptr = buf;
	int i, n;
	n = duk_get_length(ctx, 1);
	if (n > 4000) {
		n = 4000;
	}
	*ptr++ = '[';
	for (i = 0; i < n; i++) {
		if (i == pivot) {
			*ptr++ = '|';
		} else if (i == lo) {
			*ptr++ = '<';
		} else if (i == hi) {
			*ptr++ = '>';
		} else if (i >= lo && i <= hi) {
			*ptr++ = '-';
		} else {
			*ptr++ = ' ';
		}
	}
	*ptr++ = ']';
	*ptr++ = '\0';

	DUK_DDD(DUK_DDDPRINT("%s   (lo=%d, hi=%d, pivot=%d)", buf, lo, hi, pivot));
}