| /* | |
| * Copyright (C) 1999-2001 Harri Porten (porten@kde.org) | |
| * Copyright (C) 2001 Peter Kelly (pmk@post.com) | |
| * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved. | |
| * | |
| * This library is free software; you can redistribute it and/or | |
| * modify it under the terms of the GNU Library General Public | |
| * License as published by the Free Software Foundation; either | |
| * version 2 of the License, or (at your option) any later version. | |
| * | |
| * This library is distributed in the hope that it will be useful, | |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| * Library General Public License for more details. | |
| * | |
| * You should have received a copy of the GNU Library General Public License | |
| * along with this library; see the file COPYING.LIB. If not, write to | |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | |
| * Boston, MA 02110-1301, USA. | |
| * | |
| */ | |
| #ifndef JSString_h | |
| #define JSString_h | |
| #include "CallFrame.h" | |
| #include "CommonIdentifiers.h" | |
| #include "Identifier.h" | |
| #include "JSNumberCell.h" | |
| #include "PropertyDescriptor.h" | |
| #include "PropertySlot.h" | |
| namespace JSC { | |
| class JSString; | |
| JSString* jsEmptyString(JSGlobalData*); | |
| JSString* jsEmptyString(ExecState*); | |
| JSString* jsString(JSGlobalData*, const UString&); // returns empty string if passed null string | |
| JSString* jsString(ExecState*, const UString&); // returns empty string if passed null string | |
| JSString* jsSingleCharacterString(JSGlobalData*, UChar); | |
| JSString* jsSingleCharacterString(ExecState*, UChar); | |
| JSString* jsSingleCharacterSubstring(ExecState*, const UString&, unsigned offset); | |
| JSString* jsSubstring(JSGlobalData*, const UString&, unsigned offset, unsigned length); | |
| JSString* jsSubstring(ExecState*, const UString&, unsigned offset, unsigned length); | |
| // Non-trivial strings are two or more characters long. | |
| // These functions are faster than just calling jsString. | |
| JSString* jsNontrivialString(JSGlobalData*, const UString&); | |
| JSString* jsNontrivialString(ExecState*, const UString&); | |
| JSString* jsNontrivialString(JSGlobalData*, const char*); | |
| JSString* jsNontrivialString(ExecState*, const char*); | |
| // Should be used for strings that are owned by an object that will | |
| // likely outlive the JSValue this makes, such as the parse tree or a | |
| // DOM object that contains a UString | |
| JSString* jsOwnedString(JSGlobalData*, const UString&); | |
| JSString* jsOwnedString(ExecState*, const UString&); | |
| typedef void (*JSStringFinalizerCallback)(JSString*, void* context); | |
| JSString* jsStringWithFinalizer(ExecState*, const UString&, JSStringFinalizerCallback callback, void* context); | |
| class JS_EXPORTCLASS JSString : public JSCell { | |
| public: | |
| friend class JIT; | |
| friend class JSGlobalData; | |
| typedef URopeImpl Rope; | |
| class RopeBuilder { | |
| public: | |
| RopeBuilder(unsigned fiberCount) | |
| : m_index(0) | |
| , m_rope(Rope::tryCreateUninitialized(fiberCount)) | |
| { | |
| } | |
| bool isOutOfMemory() { return !m_rope; } | |
| void append(Rope::Fiber& fiber) | |
| { | |
| ASSERT(m_rope); | |
| m_rope->initializeFiber(m_index, fiber); | |
| } | |
| void append(const UString& string) | |
| { | |
| ASSERT(m_rope); | |
| m_rope->initializeFiber(m_index, string.rep()); | |
| } | |
| void append(JSString* jsString) | |
| { | |
| if (jsString->isRope()) { | |
| for (unsigned i = 0; i < jsString->m_fiberCount; ++i) | |
| append(jsString->m_other.m_fibers[i]); | |
| } else | |
| append(jsString->string()); | |
| } | |
| PassRefPtr<Rope> release() | |
| { | |
| ASSERT(m_index == m_rope->fiberCount()); | |
| return m_rope.release(); | |
| } | |
| unsigned length() { return m_rope->length(); } | |
| private: | |
| unsigned m_index; | |
| RefPtr<Rope> m_rope; | |
| }; | |
| ALWAYS_INLINE JSString(JSGlobalData* globalData, const UString& value) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(value.size()) | |
| , m_value(value) | |
| , m_fiberCount(0) | |
| { | |
| Heap::heap(this)->reportExtraMemoryCost(value.cost()); | |
| } | |
| enum HasOtherOwnerType { HasOtherOwner }; | |
| JSString(JSGlobalData* globalData, const UString& value, HasOtherOwnerType) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(value.size()) | |
| , m_value(value) | |
| , m_fiberCount(0) | |
| { | |
| } | |
| JSString(JSGlobalData* globalData, PassRefPtr<UString::Rep> value, HasOtherOwnerType) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(value->length()) | |
| , m_value(value) | |
| , m_fiberCount(0) | |
| { | |
| } | |
| JSString(JSGlobalData* globalData, PassRefPtr<Rope> rope) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(rope->length()) | |
| , m_fiberCount(1) | |
| { | |
| m_other.m_fibers[0] = rope.releaseRef(); | |
| } | |
| // This constructor constructs a new string by concatenating s1 & s2. | |
| // This should only be called with fiberCount <= 3. | |
| JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, JSString* s2) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(s1->length() + s2->length()) | |
| , m_fiberCount(fiberCount) | |
| { | |
| ASSERT(fiberCount <= s_maxInternalRopeLength); | |
| unsigned index = 0; | |
| appendStringInConstruct(index, s1); | |
| appendStringInConstruct(index, s2); | |
| ASSERT(fiberCount == index); | |
| } | |
| // This constructor constructs a new string by concatenating s1 & s2. | |
| // This should only be called with fiberCount <= 3. | |
| JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, const UString& u2) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(s1->length() + u2.size()) | |
| , m_fiberCount(fiberCount) | |
| { | |
| ASSERT(fiberCount <= s_maxInternalRopeLength); | |
| unsigned index = 0; | |
| appendStringInConstruct(index, s1); | |
| appendStringInConstruct(index, u2); | |
| ASSERT(fiberCount == index); | |
| } | |
| // This constructor constructs a new string by concatenating s1 & s2. | |
| // This should only be called with fiberCount <= 3. | |
| JSString(JSGlobalData* globalData, unsigned fiberCount, const UString& u1, JSString* s2) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(u1.size() + s2->length()) | |
| , m_fiberCount(fiberCount) | |
| { | |
| ASSERT(fiberCount <= s_maxInternalRopeLength); | |
| unsigned index = 0; | |
| appendStringInConstruct(index, u1); | |
| appendStringInConstruct(index, s2); | |
| ASSERT(fiberCount == index); | |
| } | |
| // This constructor constructs a new string by concatenating v1, v2 & v3. | |
| // This should only be called with fiberCount <= 3 ... which since every | |
| // value must require a fiberCount of at least one implies that the length | |
| // for each value must be exactly 1! | |
| JSString(ExecState* exec, JSValue v1, JSValue v2, JSValue v3) | |
| : JSCell(exec->globalData().stringStructure.get()) | |
| , m_length(0) | |
| , m_fiberCount(s_maxInternalRopeLength) | |
| { | |
| unsigned index = 0; | |
| appendValueInConstructAndIncrementLength(exec, index, v1); | |
| appendValueInConstructAndIncrementLength(exec, index, v2); | |
| appendValueInConstructAndIncrementLength(exec, index, v3); | |
| ASSERT(index == s_maxInternalRopeLength); | |
| } | |
| JSString(JSGlobalData* globalData, const UString& value, JSStringFinalizerCallback finalizer, void* context) | |
| : JSCell(globalData->stringStructure.get()) | |
| , m_length(value.size()) | |
| , m_value(value) | |
| , m_fiberCount(0) | |
| { | |
| // nasty hack because we can't union non-POD types | |
| m_other.m_finalizerCallback = finalizer; | |
| m_other.m_finalizerContext = context; | |
| Heap::heap(this)->reportExtraMemoryCost(value.cost()); | |
| } | |
| ~JSString() | |
| { | |
| ASSERT(vptr() == JSGlobalData::jsStringVPtr); | |
| for (unsigned i = 0; i < m_fiberCount; ++i) | |
| m_other.m_fibers[i]->deref(); | |
| if (!m_fiberCount && m_other.m_finalizerCallback) | |
| m_other.m_finalizerCallback(this, m_other.m_finalizerContext); | |
| } | |
| const UString& value(ExecState* exec) const | |
| { | |
| if (isRope()) | |
| resolveRope(exec); | |
| return m_value; | |
| } | |
| const UString tryGetValue() const | |
| { | |
| // If this is a rope, m_value should be null - | |
| // if this is not a rope, m_value should be non-null. | |
| ASSERT(isRope() == m_value.isNull()); | |
| return m_value; | |
| } | |
| unsigned length() { return m_length; } | |
| bool getStringPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&); | |
| bool getStringPropertySlot(ExecState*, unsigned propertyName, PropertySlot&); | |
| bool getStringPropertyDescriptor(ExecState*, const Identifier& propertyName, PropertyDescriptor&); | |
| bool canGetIndex(unsigned i) { return i < m_length; } | |
| JSString* getIndex(ExecState*, unsigned); | |
| JSString* getIndexSlowCase(ExecState*, unsigned); | |
| static PassRefPtr<Structure> createStructure(JSValue proto) { return Structure::create(proto, TypeInfo(StringType, OverridesGetOwnPropertySlot | NeedsThisConversion), AnonymousSlotCount); } | |
| private: | |
| enum VPtrStealingHackType { VPtrStealingHack }; | |
| JSString(VPtrStealingHackType) | |
| : JSCell(0) | |
| , m_fiberCount(0) | |
| { | |
| } | |
| void resolveRope(ExecState*) const; | |
| void appendStringInConstruct(unsigned& index, const UString& string) | |
| { | |
| UStringImpl* impl = string.rep(); | |
| impl->ref(); | |
| m_other.m_fibers[index++] = impl; | |
| } | |
| void appendStringInConstruct(unsigned& index, JSString* jsString) | |
| { | |
| if (jsString->isRope()) { | |
| for (unsigned i = 0; i < jsString->m_fiberCount; ++i) { | |
| Rope::Fiber fiber = jsString->m_other.m_fibers[i]; | |
| fiber->ref(); | |
| m_other.m_fibers[index++] = fiber; | |
| } | |
| } else | |
| appendStringInConstruct(index, jsString->string()); | |
| } | |
| void appendValueInConstructAndIncrementLength(ExecState* exec, unsigned& index, JSValue v) | |
| { | |
| if (v.isString()) { | |
| ASSERT(asCell(v)->isString()); | |
| JSString* s = static_cast<JSString*>(asCell(v)); | |
| ASSERT(s->fiberCount() == 1); | |
| appendStringInConstruct(index, s); | |
| m_length += s->length(); | |
| } else { | |
| UString u(v.toString(exec)); | |
| UStringImpl* impl = u.rep(); | |
| impl->ref(); | |
| m_other.m_fibers[index++] = impl; | |
| m_length += u.size(); | |
| } | |
| } | |
| virtual JSValue toPrimitive(ExecState*, PreferredPrimitiveType) const; | |
| virtual bool getPrimitiveNumber(ExecState*, double& number, JSValue& value); | |
| virtual bool toBoolean(ExecState*) const; | |
| virtual double toNumber(ExecState*) const; | |
| virtual JSObject* toObject(ExecState*) const; | |
| virtual UString toString(ExecState*) const; | |
| virtual JSObject* toThisObject(ExecState*) const; | |
| virtual UString toThisString(ExecState*) const; | |
| virtual JSString* toThisJSString(ExecState*); | |
| // Actually getPropertySlot, not getOwnPropertySlot (see JSCell). | |
| virtual bool getOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&); | |
| virtual bool getOwnPropertySlot(ExecState*, unsigned propertyName, PropertySlot&); | |
| virtual bool getOwnPropertyDescriptor(ExecState*, const Identifier&, PropertyDescriptor&); | |
| static const unsigned s_maxInternalRopeLength = 3; | |
| // A string is represented either by a UString or a Rope. | |
| unsigned m_length; | |
| mutable UString m_value; | |
| mutable unsigned m_fiberCount; | |
| // This structure exists to support a temporary workaround for a GC issue. | |
| struct JSStringFinalizerStruct { | |
| JSStringFinalizerStruct() : m_finalizerCallback(0) {} | |
| union { | |
| mutable Rope::Fiber m_fibers[s_maxInternalRopeLength]; | |
| struct { | |
| JSStringFinalizerCallback m_finalizerCallback; | |
| void* m_finalizerContext; | |
| }; | |
| }; | |
| } m_other; | |
| bool isRope() const { return m_fiberCount; } | |
| UString& string() { ASSERT(!isRope()); return m_value; } | |
| unsigned fiberCount() { return m_fiberCount ? m_fiberCount : 1; } | |
| friend JSValue jsString(ExecState* exec, JSString* s1, JSString* s2); | |
| friend JSValue jsString(ExecState* exec, const UString& u1, JSString* s2); | |
| friend JSValue jsString(ExecState* exec, JSString* s1, const UString& u2); | |
| friend JSValue jsString(ExecState* exec, Register* strings, unsigned count); | |
| friend JSValue jsString(ExecState* exec, JSValue thisValue, const ArgList& args); | |
| friend JSString* jsStringWithFinalizer(ExecState*, const UString&, JSStringFinalizerCallback callback, void* context); | |
| }; | |
| JSString* asString(JSValue); | |
| // When an object is created from a different DLL, MSVC changes vptr to a "local" one right after invoking a constructor, | |
| // see <http://groups.google.com/group/microsoft.public.vc.language/msg/55cdcefeaf770212>. | |
| // This breaks isJSString(), and we don't need that hack anyway, so we change vptr back to primary one. | |
| // The below function must be called by any inline function that invokes a JSString constructor. | |
| #if COMPILER(MSVC) && !defined(BUILDING_JavaScriptCore) | |
| inline JSString* fixupVPtr(JSGlobalData* globalData, JSString* string) { string->setVPtr(globalData->jsStringVPtr); return string; } | |
| #else | |
| inline JSString* fixupVPtr(JSGlobalData*, JSString* string) { return string; } | |
| #endif | |
| inline JSString* asString(JSValue value) | |
| { | |
| ASSERT(asCell(value)->isString()); | |
| return static_cast<JSString*>(asCell(value)); | |
| } | |
| inline JSString* jsEmptyString(JSGlobalData* globalData) | |
| { | |
| return globalData->smallStrings.emptyString(globalData); | |
| } | |
| inline JSString* jsSingleCharacterString(JSGlobalData* globalData, UChar c) | |
| { | |
| if (c <= 0xFF) | |
| return globalData->smallStrings.singleCharacterString(globalData, c); | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(&c, 1))); | |
| } | |
| inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset) | |
| { | |
| JSGlobalData* globalData = &exec->globalData(); | |
| ASSERT(offset < static_cast<unsigned>(s.size())); | |
| UChar c = s.data()[offset]; | |
| if (c <= 0xFF) | |
| return globalData->smallStrings.singleCharacterString(globalData, c); | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(UString::Rep::create(s.rep(), offset, 1)))); | |
| } | |
| inline JSString* jsNontrivialString(JSGlobalData* globalData, const char* s) | |
| { | |
| ASSERT(s); | |
| ASSERT(s[0]); | |
| ASSERT(s[1]); | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, s)); | |
| } | |
| inline JSString* jsNontrivialString(JSGlobalData* globalData, const UString& s) | |
| { | |
| ASSERT(s.size() > 1); | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, s)); | |
| } | |
| inline JSString* JSString::getIndex(ExecState* exec, unsigned i) | |
| { | |
| ASSERT(canGetIndex(i)); | |
| if (isRope()) | |
| return getIndexSlowCase(exec, i); | |
| ASSERT(i < m_value.size()); | |
| return jsSingleCharacterSubstring(exec, value(exec), i); | |
| } | |
| inline JSString* jsString(JSGlobalData* globalData, const UString& s) | |
| { | |
| int size = s.size(); | |
| if (!size) | |
| return globalData->smallStrings.emptyString(globalData); | |
| if (size == 1) { | |
| UChar c = s.data()[0]; | |
| if (c <= 0xFF) | |
| return globalData->smallStrings.singleCharacterString(globalData, c); | |
| } | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, s)); | |
| } | |
| inline JSString* jsStringWithFinalizer(ExecState* exec, const UString& s, JSStringFinalizerCallback callback, void* context) | |
| { | |
| ASSERT(s.size() && (s.size() > 1 || s.data()[0] > 0xFF)); | |
| JSGlobalData* globalData = &exec->globalData(); | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, s, callback, context)); | |
| } | |
| inline JSString* jsSubstring(JSGlobalData* globalData, const UString& s, unsigned offset, unsigned length) | |
| { | |
| ASSERT(offset <= static_cast<unsigned>(s.size())); | |
| ASSERT(length <= static_cast<unsigned>(s.size())); | |
| ASSERT(offset + length <= static_cast<unsigned>(s.size())); | |
| if (!length) | |
| return globalData->smallStrings.emptyString(globalData); | |
| if (length == 1) { | |
| UChar c = s.data()[offset]; | |
| if (c <= 0xFF) | |
| return globalData->smallStrings.singleCharacterString(globalData, c); | |
| } | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(UString::Rep::create(s.rep(), offset, length)), JSString::HasOtherOwner)); | |
| } | |
| inline JSString* jsOwnedString(JSGlobalData* globalData, const UString& s) | |
| { | |
| int size = s.size(); | |
| if (!size) | |
| return globalData->smallStrings.emptyString(globalData); | |
| if (size == 1) { | |
| UChar c = s.data()[0]; | |
| if (c <= 0xFF) | |
| return globalData->smallStrings.singleCharacterString(globalData, c); | |
| } | |
| return fixupVPtr(globalData, new (globalData) JSString(globalData, s, JSString::HasOtherOwner)); | |
| } | |
| inline JSString* jsEmptyString(ExecState* exec) { return jsEmptyString(&exec->globalData()); } | |
| inline JSString* jsString(ExecState* exec, const UString& s) { return jsString(&exec->globalData(), s); } | |
| inline JSString* jsSingleCharacterString(ExecState* exec, UChar c) { return jsSingleCharacterString(&exec->globalData(), c); } | |
| inline JSString* jsSubstring(ExecState* exec, const UString& s, unsigned offset, unsigned length) { return jsSubstring(&exec->globalData(), s, offset, length); } | |
| inline JSString* jsNontrivialString(ExecState* exec, const UString& s) { return jsNontrivialString(&exec->globalData(), s); } | |
| inline JSString* jsNontrivialString(ExecState* exec, const char* s) { return jsNontrivialString(&exec->globalData(), s); } | |
| inline JSString* jsOwnedString(ExecState* exec, const UString& s) { return jsOwnedString(&exec->globalData(), s); } | |
| ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot) | |
| { | |
| if (propertyName == exec->propertyNames().length) { | |
| slot.setValue(jsNumber(exec, m_length)); | |
| return true; | |
| } | |
| bool isStrictUInt32; | |
| unsigned i = propertyName.toStrictUInt32(&isStrictUInt32); | |
| if (isStrictUInt32 && i < m_length) { | |
| slot.setValue(getIndex(exec, i)); | |
| return true; | |
| } | |
| return false; | |
| } | |
| ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot) | |
| { | |
| if (propertyName < m_length) { | |
| slot.setValue(getIndex(exec, propertyName)); | |
| return true; | |
| } | |
| return false; | |
| } | |
| inline bool isJSString(JSGlobalData* globalData, JSValue v) { return v.isCell() && v.asCell()->vptr() == globalData->jsStringVPtr; } | |
| // --- JSValue inlines ---------------------------- | |
| inline JSString* JSValue::toThisJSString(ExecState* exec) | |
| { | |
| return isCell() ? asCell()->toThisJSString(exec) : jsString(exec, toString(exec)); | |
| } | |
| inline UString JSValue::toString(ExecState* exec) const | |
| { | |
| if (isString()) | |
| return static_cast<JSString*>(asCell())->value(exec); | |
| if (isInt32()) | |
| return exec->globalData().numericStrings.add(asInt32()); | |
| if (isDouble()) | |
| return exec->globalData().numericStrings.add(asDouble()); | |
| if (isTrue()) | |
| return "true"; | |
| if (isFalse()) | |
| return "false"; | |
| if (isNull()) | |
| return "null"; | |
| if (isUndefined()) | |
| return "undefined"; | |
| ASSERT(isCell()); | |
| return asCell()->toString(exec); | |
| } | |
| inline UString JSValue::toPrimitiveString(ExecState* exec) const | |
| { | |
| if (isString()) | |
| return static_cast<JSString*>(asCell())->value(exec); | |
| if (isInt32()) | |
| return exec->globalData().numericStrings.add(asInt32()); | |
| if (isDouble()) | |
| return exec->globalData().numericStrings.add(asDouble()); | |
| if (isTrue()) | |
| return "true"; | |
| if (isFalse()) | |
| return "false"; | |
| if (isNull()) | |
| return "null"; | |
| if (isUndefined()) | |
| return "undefined"; | |
| ASSERT(isCell()); | |
| return asCell()->toPrimitive(exec, NoPreference).toString(exec); | |
| } | |
| } // namespace JSC | |
| #endif // JSString_h |