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pjs/js/js2/jstypes.cpp

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express oqr
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is the JavaScript 2 Prototype.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the
* terms of the GNU Public License (the "GPL"), in which case the
* provisions of the GPL are applicable instead of those above.
* If you wish to allow use of your version of this file only
* under the terms of the GPL and not to allow others to use your
* version of this file under the NPL, indicate your decision by
* deleting the provisions above and replace them with the notice
* and other provisions required by the GPL. If you do not delete
* the provisions above, a recipient may use your version of this
* file under either the NPL or the GPL.
*/
#include "jstypes.h"
#include "jsclasses.h"
#include "numerics.h"
#include "icodegenerator.h"
#include "interpreter.h"
namespace JavaScript {
namespace JSTypes {
using namespace JSClasses;
using namespace Interpreter;
/********** Object Object Stuff **************************/
static JSValue object_toString(Context *, const JSValues& argv)
{
if (argv.size() > 0) {
JSString *s = new JSString("[object ");
JSValue theThis = argv[0];
ASSERT(theThis.isObject());
s->append(theThis.object->getClass());
s->append("]");
return JSValue(s);
}
return kUndefinedValue;
}
static JSValue object_constructor(Context *, const JSValues& /*argv*/)
{
// argv[0] will be NULL
return JSValue(new JSObject());
}
struct ObjectFunctionEntry {
char *name;
JSNativeFunction::JSCode fn;
} ObjectFunctions[] = {
{ "toString", object_toString },
};
JSObject* JSObject::ObjectPrototypeObject = JSObject::initJSObject();
JSString* JSObject::ObjectString = new JSString("Object");
// This establishes the ur-prototype, there's a timing issue
// here - the JSObject static initializers have to run before
// any other JSObject objects are constructed.
JSObject *JSObject::initJSObject()
{
JSObject *result = new JSObject();
for (uint i = 0; i < sizeof(ObjectFunctions) / sizeof(ObjectFunctionEntry); i++)
result->setProperty(widenCString(ObjectFunctions[i].name), JSValue(new JSNativeFunction(ObjectFunctions[i].fn) ) );
return result;
}
void JSObject::initObjectObject(JSScope *)
{
// The ObjectPrototypeObject has already been constructed by static initialization.
// JSNativeFunction *objCon = new JSNativeFunction(objectConstructor);
// objCon->setProperty(widenCString("prototype"), JSValue(ObjectPrototypeObject));
// g->setProperty(*ObjectString, JSValue(objCon));
}
/********** Function Object Stuff **************************/
// An empty function that returns undefined
static JSValue functionPrototypeFunction(Context *, const JSValues &)
{
return kUndefinedValue;
}
static JSValue function_constructor(Context *cx, const JSValues& argv)
{
// build a function from the arguments
// argv[0] will be NULL
if (argv.size() >= 2) {
int32 parameterCount = argv.size() - 2;
JSString source("function (");
for (int32 i = 0; i < parameterCount; i++) {
source.append((JSValue::valueToString(argv[i + 1]).string));
if (i < (parameterCount - 1)) source.append(",");
}
source.append(") {");
source.append(JSValue::valueToString(argv[argv.size() - 1]).string);
source.append("}");
JSFunction *f = new JSFunction(cx->compileFunction(source));
f->setProperty(widenCString("length"), JSValue(parameterCount));
JSObject *obj = new JSObject();
f->setProperty(widenCString("prototype"), JSValue(obj));
f->setProperty(widenCString("constructor"), JSValue(obj));
return JSValue(f);
}
return kUndefinedValue;
}
static JSValue function_toString(Context *, const JSValues &)
{
return JSValue(new JSString("function XXX() { }" ));
}
static JSValue function_apply(Context *, const JSValues &)
{
// XXX
return kUndefinedValue;
}
static JSValue function_call(Context *, const JSValues &)
{
// XXX
return kUndefinedValue;
}
JSString* JSFunction::FunctionString = new JSString("Function");
JSObject* JSFunction::FunctionPrototypeObject = NULL; // the 'original Function prototype object'
struct FunctionFunctionEntry {
char *name;
JSNativeFunction::JSCode fn;
} FunctionFunctions[] = {
{ "constructor", function_constructor },
{ "toString", function_toString },
{ "apply", function_apply },
{ "call", function_call },
};
void JSFunction::initFunctionObject(JSScope *g)
{
// first build the Function Prototype Object
FunctionPrototypeObject = new JSNativeFunction(functionPrototypeFunction);
for (uint i = 0; i < sizeof(FunctionFunctions) / sizeof(FunctionFunctionEntry); i++)
FunctionPrototypeObject->setProperty(widenCString(FunctionFunctions[i].name), JSValue(new JSNativeFunction(FunctionFunctions[i].fn) ) );
ASSERT(g->getProperty(*FunctionString).isObject());
JSObject *functionVariable = g->getProperty(*FunctionString).object;
// there is actually no connection between the 'prototype' property of the function object
// and the prototype set for each new function - the constructor has implicit access to
// the 'original Function prototype object'
functionVariable->setProperty(widenCString("prototype"), JSValue(FunctionPrototypeObject)); // should be DontEnum, DontDelete, ReadOnly
}
/********** Boolean Object Stuff **************************/
JSString* JSBoolean::BooleanString = new JSString("Boolean");
static JSValue boolean_constructor(Context *, const JSValues& argv)
{
// argv[0] will be NULL
if (argv.size() > 1)
return JSValue(new JSBoolean(JSValue::valueToBoolean(argv[1]).boolean));
else
return JSValue(new JSBoolean(false));
}
static JSValue boolean_toString(Context *, const JSValues& argv)
{
if (argv.size() > 0) {
JSValue theThis = argv[0];
if (theThis.isObject()) {
JSBoolean *b = dynamic_cast<JSBoolean *>(theThis.object);
if (b)
return JSValue(new JSString(b->getValue() ? "true" : "false"));
else
throw new JSException("TypeError : Boolean::toString called on non boolean object");
}
else
throw new JSException("TypeError : Boolean::toString called on non object");
}
return kUndefinedValue;
}
static JSValue boolean_valueOf(Context *, const JSValues&)
{
return kUndefinedValue;
}
JSObject *JSBoolean::BooleanPrototypeObject = NULL;
struct BooleanFunctionEntry {
char *name;
JSNativeFunction::JSCode fn;
} BooleanFunctions[] = {
{ "constructor", boolean_constructor },
{ "toString", boolean_toString },
{ "valueOf", boolean_valueOf },
};
void JSBoolean::initBooleanObject(JSScope *g)
{
BooleanPrototypeObject = new JSObject();
BooleanPrototypeObject->setClass(new JSString(BooleanString));
for (uint i = 0; i < sizeof(BooleanFunctions) / sizeof(BooleanFunctionEntry); i++)
BooleanPrototypeObject->setProperty(widenCString(BooleanFunctions[i].name), JSValue(new JSNativeFunction(BooleanFunctions[i].fn) ) );
ASSERT(g->getProperty(*BooleanString).isObject());
JSObject *booleanVariable = g->getProperty(*BooleanString).object;
booleanVariable->setProperty(widenCString("prototype"), JSValue(BooleanPrototypeObject)); // should be DontEnum, DontDelete, ReadOnly
}
/********** Date Object Stuff **************************/
static JSValue date_constructor(Context *, const JSValues&)
{
// return JSValue(new JSDate());
return JSValue(new JSObject());
}
static JSValue date_invokor(Context *, const JSValues&)
{
return JSValue(new JSString("now"));
}
/**************************************************************************************/
JSType Any_Type = JSType(widenCString("any"), NULL);
JSType Integer_Type = JSType(widenCString("Integer"), &Any_Type);
JSType Number_Type = JSType(widenCString("Number"), &Integer_Type);
JSType Character_Type = JSType(widenCString("Character"), &Any_Type);
JSType String_Type = JSType(widenCString("String"), &Character_Type);
JSType Function_Type = JSType(widenCString("Function"), &Any_Type, new JSNativeFunction(function_constructor), new JSNativeFunction(function_constructor));
JSType Array_Type = JSType(widenCString("Array"), &Any_Type);
JSType Type_Type = JSType(widenCString("Type"), &Any_Type);
JSType Boolean_Type = JSType(widenCString("Boolean"), &Any_Type, new JSNativeFunction(boolean_constructor), new JSNativeFunction(boolean_constructor));
JSType Null_Type = JSType(widenCString("Null"), &Any_Type);
JSType Void_Type = JSType(widenCString("void"), &Any_Type);
JSType None_Type = JSType(widenCString("none"), &Any_Type);
JSType Object_Type = JSType(widenCString("Object"), NULL, new JSNativeFunction(object_constructor));
JSType Date_Type = JSType(widenCString("Date"), NULL, new JSNativeFunction(date_constructor), new JSNativeFunction(date_invokor));
#ifdef IS_LITTLE_ENDIAN
#define JSDOUBLE_HI32(x) (((uint32 *)&(x))[1])
#define JSDOUBLE_LO32(x) (((uint32 *)&(x))[0])
#else
#define JSDOUBLE_HI32(x) (((uint32 *)&(x))[0])
#define JSDOUBLE_LO32(x) (((uint32 *)&(x))[1])
#endif
#define JSDOUBLE_HI32_SIGNBIT 0x80000000
#define JSDOUBLE_HI32_EXPMASK 0x7ff00000
#define JSDOUBLE_HI32_MANTMASK 0x000fffff
#define JSDOUBLE_IS_NaN(x) \
((JSDOUBLE_HI32(x) & JSDOUBLE_HI32_EXPMASK) == JSDOUBLE_HI32_EXPMASK && \
(JSDOUBLE_LO32(x) || (JSDOUBLE_HI32(x) & JSDOUBLE_HI32_MANTMASK)))
#define JSDOUBLE_IS_INFINITE(x) \
((JSDOUBLE_HI32(x) & ~JSDOUBLE_HI32_SIGNBIT) == JSDOUBLE_HI32_EXPMASK && \
!JSDOUBLE_LO32(x))
#define JSDOUBLE_IS_FINITE(x) \
((JSDOUBLE_HI32(x) & JSDOUBLE_HI32_EXPMASK) != JSDOUBLE_HI32_EXPMASK)
#define JSDOUBLE_IS_NEGZERO(d) (JSDOUBLE_HI32(d) == JSDOUBLE_HI32_SIGNBIT && \
JSDOUBLE_LO32(d) == 0)
// the canonical undefined value, etc.
const JSValue kUndefinedValue;
const JSValue kNaNValue = JSValue(nan);
const JSValue kTrueValue = JSValue(true);
const JSValue kFalseValue = JSValue(false);
const JSValue kNullValue = JSValue((JSObject*)NULL);
const JSValue kNegativeZero = JSValue(-0.0);
const JSValue kPositiveZero = JSValue(0.0);
const JSValue kNegativeInfinity = JSValue(negativeInfinity);
const JSValue kPositiveInfinity = JSValue(positiveInfinity);
const JSType *JSValue::getType() const
{
switch (tag) {
case JSValue::i32_tag:
return &Integer_Type;
case JSValue::u32_tag:
return &Integer_Type;
case JSValue::integer_tag:
return &Integer_Type;
case JSValue::f64_tag:
return &Number_Type;
case JSValue::object_tag:
{
//
// XXX why isn't there a class for Object? XXX
//
JSClass *clazz = dynamic_cast<JSClass *>(object->getType());
if (clazz)
return clazz;
else
return &Any_Type;
}
case JSValue::array_tag:
return &Array_Type;
case JSValue::function_tag:
return &Function_Type;
case JSValue::string_tag:
return &String_Type;
case JSValue::boolean_tag:
return &Boolean_Type;
case JSValue::undefined_tag:
return &Void_Type;
case JSValue::type_tag:
return &Type_Type;
default:
NOT_REACHED("Bad tag");
return &None_Type;
}
}
bool JSValue::isNaN() const
{
ASSERT(isNumber());
switch (tag) {
case i32_tag:
case u32_tag:
return false;
case integer_tag:
case f64_tag:
return JSDOUBLE_IS_NaN(f64);
default:
NOT_REACHED("Broken compiler?");
return true;
}
}
bool JSValue::isNegativeInfinity() const
{
ASSERT(isNumber());
switch (tag) {
case i32_tag:
case u32_tag:
return false;
case integer_tag:
case f64_tag:
return (f64 < 0) && JSDOUBLE_IS_INFINITE(f64);
default:
NOT_REACHED("Broken compiler?");
return true;
}
}
bool JSValue::isPositiveInfinity() const
{
ASSERT(isNumber());
switch (tag) {
case i32_tag:
case u32_tag:
return false;
case integer_tag:
case f64_tag:
return (f64 > 0) && JSDOUBLE_IS_INFINITE(f64);
default:
NOT_REACHED("Broken compiler?");
return true;
}
}
bool JSValue::isNegativeZero() const
{
ASSERT(isNumber());
switch (tag) {
case i32_tag:
case u32_tag:
return false;
case integer_tag:
case f64_tag:
return JSDOUBLE_IS_NEGZERO(f64);
default:
NOT_REACHED("Broken compiler?");
return true;
}
}
bool JSValue::isPositiveZero() const
{
ASSERT(isNumber());
switch (tag) {
case i32_tag:
return (i32 == 0);
case u32_tag:
return (u32 == 0);
case integer_tag:
case f64_tag:
return (f64 == 0.0) && !JSDOUBLE_IS_NEGZERO(f64);
default:
NOT_REACHED("Broken compiler?");
return true;
}
}
int JSValue::operator==(const JSValue& value) const
{
if (this->tag == value.tag) {
#define CASE(T) case T##_tag: return (this->T == value.T)
switch (tag) {
CASE(i8); CASE(u8);
CASE(i16); CASE(u16);
CASE(i32); CASE(u32); CASE(f32);
CASE(i64); CASE(u64); CASE(f64);
CASE(object); CASE(array); CASE(function); CASE(string);
CASE(type); CASE(boolean);
#undef CASE
case integer_tag : return (this->f64 == value.f64);
// question: are all undefined values equal to one another?
case undefined_tag: return 1;
default:
NOT_REACHED("Broken compiler?");
}
}
return 0;
}
Formatter& operator<<(Formatter& f, JSObject& obj)
{
obj.printProperties(f);
return f;
}
void JSObject::printProperties(Formatter& f)
{
for (JSProperties::const_iterator i = mProperties.begin(); i != mProperties.end(); i++) {
f << (*i).first << " : " << (*i).second;
f << "\n";
}
}
String getRegisterValue(const JSValues& registerList, Register reg)
{
StringFormatter sf;
if (reg == NotARegister)
sf << "<NaR>";
else
sf << "R" << reg << '=' << registerList[reg];
return sf;
}
Formatter& operator<<(Formatter& f, const JSValue& value)
{
switch (value.tag) {
case JSValue::i32_tag:
f << float64(value.i32);
break;
case JSValue::u32_tag:
f << float64(value.u32);
break;
case JSValue::integer_tag:
case JSValue::f64_tag:
f << value.f64;
break;
case JSValue::object_tag:
printFormat(f, "Object @ 0x%08X\n", value.object);
f << *value.object;
break;
case JSValue::array_tag: {
JSArray *a = value.array;
f << "[";
for (uint32 i = 0; i < a->length(); i++) {
f << (*a)[i];
if (i < (a->length() - 1))
f << ", ";
}
f << "] {" << *(static_cast<JSObject*>(value.array)) << "}";
// printFormat(f, "Array @ 0x%08X", value.array);
}
break;
case JSValue::function_tag:
printFormat(f, "Function @ 0x%08X", value.function);
break;
case JSValue::string_tag:
f << "\"" << *value.string << "\"";
break;
case JSValue::boolean_tag:
f << ((value.boolean) ? "true" : "false");
break;
case JSValue::undefined_tag:
f << "undefined";
break;
case JSValue::type_tag:
printFormat(f, "Type @ 0x%08X\n", value.type);
f << *value.type;
break;
case JSValue::uninitialized_tag:
f << "uninitialized";
break;
default:
NOT_REACHED("Bad tag");
}
return f;
}
JSValue JSValue::toPrimitive(ECMA_type /*hint*/) const
{
JSObject *obj;
switch (tag) {
case i32_tag:
case u32_tag:
case integer_tag:
case f64_tag:
case string_tag:
case boolean_tag:
case undefined_tag:
return *this;
case object_tag:
obj = object;
break;
case array_tag:
obj = array;
break;
case function_tag:
obj = function;
break;
default:
NOT_REACHED("Bad tag");
return kUndefinedValue;
}
const JSValue &toString = obj->getProperty(widenCString("toString"));
if (toString.isObject()) {
if (toString.isFunction()) {
}
else // right? The spec doesn't say
throw new JSException("Runtime error from toPrimitive"); // XXX
}
const JSValue &valueOf = obj->getProperty(widenCString("valueOf"));
if (!valueOf.isObject())
throw new JSException("Runtime error from toPrimitive"); // XXX
return kUndefinedValue;
}
JSValue JSValue::valueToString(const JSValue& value) // can assume value is not a string
{
const char* chrp;
char buf[dtosStandardBufferSize];
switch (value.tag) {
case i32_tag:
chrp = doubleToStr(buf, dtosStandardBufferSize, value.i32, dtosStandard, 0);
break;
case u32_tag:
chrp = doubleToStr(buf, dtosStandardBufferSize, value.u32, dtosStandard, 0);
break;
case integer_tag:
case f64_tag:
chrp = doubleToStr(buf, dtosStandardBufferSize, value.f64, dtosStandard, 0);
break;
case object_tag:
chrp = "object";
break;
case array_tag:
chrp = "array";
break;
case function_tag:
chrp = "function";
break;
case string_tag:
return value;
case boolean_tag:
chrp = (value.boolean) ? "true" : "false";
break;
case undefined_tag:
chrp = "undefined";
break;
default:
NOT_REACHED("Bad tag");
}
return JSValue(new JSString(chrp));
}
JSValue JSValue::valueToNumber(const JSValue& value) // can assume value is not a number
{
switch (value.tag) {
case i32_tag:
return JSValue((float64)value.i32);
case u32_tag:
return JSValue((float64)value.u32);
case integer_tag:
case f64_tag:
return value;
case string_tag:
{
JSString* str = value.string;
const char16 *numEnd;
double d = stringToDouble(str->begin(), str->end(), numEnd);
return JSValue(d);
}
case object_tag:
case array_tag:
case function_tag:
// XXX more needed :
// toNumber(toPrimitive(hint Number))
return kUndefinedValue;
case boolean_tag:
return JSValue((value.boolean) ? 1.0 : 0.0);
case undefined_tag:
return kNaNValue;
default:
NOT_REACHED("Bad tag");
return kUndefinedValue;
}
}
JSValue JSValue::valueToInteger(const JSValue& value)
{
JSValue result = valueToNumber(value);
ASSERT(result.tag == f64_tag);
result.tag = i32_tag;
bool neg = (result.f64 < 0);
result.i32 = (int32)floor((neg) ? -result.f64 : result.f64);
result.i32 = (neg) ? -result.i32 : result.i32;
return result;
}
JSValue JSValue::valueToBoolean(const JSValue& value)
{
switch (value.tag) {
case i32_tag:
return JSValue(value.i32 != 0);
case u32_tag:
return JSValue(value.u32 != 0);
case integer_tag:
case f64_tag:
return JSValue(!(value.f64 == 0.0) || JSDOUBLE_IS_NaN(value.f64));
case string_tag:
return JSValue(value.string->length() != 0);
case boolean_tag:
return value;
case object_tag:
case array_tag:
case function_tag:
return kTrueValue;
case undefined_tag:
return kFalseValue;
default:
NOT_REACHED("Bad tag");
return kUndefinedValue;
}
}
static const double two32 = 4294967296.0;
static const double two31 = 2147483648.0;
JSValue JSValue::valueToInt32(const JSValue& value)
{
double d;
switch (value.tag) {
case i32_tag:
return value;
case u32_tag:
d = value.u32;
break;
case integer_tag:
case f64_tag:
d = value.f64;
break;
case string_tag:
{
JSString* str = value.string;
const char16 *numEnd;
d = stringToDouble(str->begin(), str->end(), numEnd);
}
break;
case boolean_tag:
return JSValue((int32)((value.boolean) ? 1 : 0));
case object_tag:
case array_tag:
case undefined_tag:
// toNumber(toPrimitive(hint Number))
return kUndefinedValue;
default:
NOT_REACHED("Bad tag");
return kUndefinedValue;
}
if ((d == 0.0) || !JSDOUBLE_IS_FINITE(d) )
return JSValue((int32)0);
d = fmod(d, two32);
d = (d >= 0) ? d : d + two32;
if (d >= two31)
return JSValue((int32)(d - two32));
else
return JSValue((int32)d);
}
JSValue JSValue::valueToUInt32(const JSValue& value)
{
double d;
switch (value.tag) {
case i32_tag:
return JSValue((uint32)value.i32);
case u32_tag:
return value;
case f64_tag:
d = value.f64;
break;
case string_tag:
{
JSString* str = value.string;
const char16 *numEnd;
d = stringToDouble(str->begin(), str->end(), numEnd);
}
break;
case boolean_tag:
return JSValue((uint32)((value.boolean) ? 1 : 0));
case object_tag:
case array_tag:
case undefined_tag:
// toNumber(toPrimitive(hint Number))
return kUndefinedValue;
default:
NOT_REACHED("Bad tag");
return kUndefinedValue;
}
if ((d == 0.0) || !JSDOUBLE_IS_FINITE(d))
return JSValue((uint32)0);
bool neg = (d < 0);
d = floor(neg ? -d : d);
d = neg ? -d : d;
d = fmod(d, two32);
d = (d >= 0) ? d : d + two32;
return JSValue((uint32)d);
}
JSValue JSValue::convert(JSType *toType)
{
if (toType == &Any_Type) // yuck, something wrong with this
// maybe the base types should be
// a family of classes, not just instances
// of JSType ???
return *this;
else if (toType == &Integer_Type)
return valueToInteger(*this);
else {
JSClass *toClass = dynamic_cast<JSClass *>(toType);
if (toClass) {
if (tag == object_tag) {
JSClass *fromClass = dynamic_cast<JSClass *>(object->getType());
if (fromClass) {
while (fromClass != toClass) {
fromClass = fromClass->getSuperClass();
if (fromClass == NULL)
throw new JSException("Can't cast to unrelated class");
}
return *this;
}
else
throw new JSException("Can't cast a generic object to a class");
}
else
throw new JSException("Can't cast a non-object to a class");
}
}
return kUndefinedValue;
}
JSFunction::~JSFunction()
{
delete mICode;
}
JSString::JSString(const String& str)
{
size_t n = str.size();
resize(n);
traits_type::copy(begin(), str.begin(), n);
}
JSString::JSString(const String* str)
{
size_t n = str->size();
resize(n);
traits_type::copy(begin(), str->begin(), n);
}
JSString::JSString(const char* str)
{
size_t n = ::strlen(str);
resize(n);
std::transform(str, str + n, begin(), JavaScript::widen);
}
void JSString::append(const char* str)
{
size_t n = ::strlen(str);
size_t oldSize = size();
resize(oldSize + n);
std::transform(str, str + n, begin() + oldSize, JavaScript::widen);
}
void JSString::append(const JSStringBase* str)
{
size_t n = str->size();
size_t oldSize = size();
resize(oldSize + n);
traits_type::copy(begin() + oldSize, str->begin(), n);
}
JSString::operator String()
{
return String(begin(), size());
}
// # of sub-type relationship between this type and the other type
// (== MAX_INT if other is not a base type)
int32 JSType::distance(const JSType *other) const
{
if (other == this)
return 0;
if (mBaseType == NULL)
return NoRelation;
int32 baseDistance = mBaseType->distance(other);
if (baseDistance != NoRelation)
++baseDistance;
return baseDistance;
}
} /* namespace JSTypes */
} /* namespace JavaScript */
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