| /* |
| * Copyright (C) 1999-2002 Harri Porten (porten@kde.org) |
| * Copyright (C) 2001 Peter Kelly (pmk@post.com) |
| * Copyright (C) 2004, 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. |
| * |
| */ |
| |
| #include "config.h" |
| #include "JSString.h" |
| |
| #include "JSGlobalObject.h" |
| #include "JSGlobalObjectFunctions.h" |
| #include "JSObject.h" |
| #include "Operations.h" |
| #include "StringObject.h" |
| #include "StringPrototype.h" |
| |
| namespace JSC { |
| |
| static const unsigned substringFromRopeCutoff = 4; |
| |
| const ClassInfo JSString::s_info = { "string", 0, 0, 0, CREATE_METHOD_TABLE(JSString) }; |
| |
| const ClassInfo* JSString::s_classinfo() { return &s_info; } |
| |
| void JSRopeString::RopeBuilder::expand() |
| { |
| ASSERT(m_index == JSRopeString::s_maxInternalRopeLength); |
| JSString* jsString = m_jsString; |
| m_jsString = jsStringBuilder(&m_globalData); |
| m_index = 0; |
| append(jsString); |
| } |
| |
| void JSString::destroy(JSCell* cell) |
| { |
| JSString* thisObject = static_cast<JSString*>(cell); |
| thisObject->JSString::~JSString(); |
| } |
| |
| void JSString::visitChildren(JSCell* cell, SlotVisitor& visitor) |
| { |
| JSString* thisObject = jsCast<JSString*>(cell); |
| Base::visitChildren(thisObject, visitor); |
| |
| MARK_LOG_MESSAGE1("[%u]: ", thisObject->length()); |
| |
| #if ENABLE(OBJECT_MARK_LOGGING) |
| if (!thisObject->isRope()) { |
| WTF::StringImpl* ourImpl = thisObject->m_value.impl(); |
| if (ourImpl->is8Bit()) |
| MARK_LOG_MESSAGE1("[8 %p]", ourImpl->characters8()); |
| else |
| MARK_LOG_MESSAGE1("[16 %p]", ourImpl->characters16()); |
| } else |
| MARK_LOG_MESSAGE0("[rope]: "); |
| #endif |
| |
| if (thisObject->isRope()) |
| static_cast<JSRopeString*>(thisObject)->visitFibers(visitor); |
| } |
| |
| void JSRopeString::visitFibers(SlotVisitor& visitor) |
| { |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) |
| visitor.append(&m_fibers[i]); |
| } |
| |
| void JSRopeString::resolveRope(ExecState* exec) const |
| { |
| ASSERT(isRope()); |
| |
| if (is8Bit()) { |
| LChar* buffer; |
| if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) { |
| Heap::heap(this)->reportExtraMemoryCost(newImpl->cost()); |
| m_value = newImpl.release(); |
| } else { |
| outOfMemory(exec); |
| return; |
| } |
| |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { |
| if (m_fibers[i]->isRope()) |
| return resolveRopeSlowCase8(buffer); |
| } |
| |
| LChar* position = buffer; |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { |
| StringImpl* string = m_fibers[i]->m_value.impl(); |
| unsigned length = string->length(); |
| StringImpl::copyChars(position, string->characters8(), length); |
| position += length; |
| m_fibers[i].clear(); |
| } |
| ASSERT((buffer + m_length) == position); |
| ASSERT(!isRope()); |
| |
| return; |
| } |
| |
| UChar* buffer; |
| if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) { |
| Heap::heap(this)->reportExtraMemoryCost(newImpl->cost()); |
| m_value = newImpl.release(); |
| } else { |
| outOfMemory(exec); |
| return; |
| } |
| |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { |
| if (m_fibers[i]->isRope()) |
| return resolveRopeSlowCase(buffer); |
| } |
| |
| UChar* position = buffer; |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { |
| StringImpl* string = m_fibers[i]->m_value.impl(); |
| unsigned length = string->length(); |
| if (string->is8Bit()) |
| StringImpl::copyChars(position, string->characters8(), length); |
| else |
| StringImpl::copyChars(position, string->characters16(), length); |
| position += length; |
| m_fibers[i].clear(); |
| } |
| ASSERT((buffer + m_length) == position); |
| ASSERT(!isRope()); |
| } |
| |
| // Overview: These functions convert a JSString from holding a string in rope form |
| // down to a simple String representation. It does so by building up the string |
| // backwards, since we want to avoid recursion, we expect that the tree structure |
| // representing the rope is likely imbalanced with more nodes down the left side |
| // (since appending to the string is likely more common) - and as such resolving |
| // in this fashion should minimize work queue size. (If we built the queue forwards |
| // we would likely have to place all of the constituent StringImpls into the |
| // Vector before performing any concatenation, but by working backwards we likely |
| // only fill the queue with the number of substrings at any given level in a |
| // rope-of-ropes.) |
| void JSRopeString::resolveRopeSlowCase8(LChar* buffer) const |
| { |
| LChar* position = buffer + m_length; // We will be working backwards over the rope. |
| Vector<JSString*, 32> workQueue; // Putting strings into a Vector is only OK because there are no GC points in this method. |
| |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { |
| workQueue.append(m_fibers[i].get()); |
| // Clearing here works only because there are no GC points in this method. |
| m_fibers[i].clear(); |
| } |
| |
| while (!workQueue.isEmpty()) { |
| JSString* currentFiber = workQueue.last(); |
| workQueue.removeLast(); |
| |
| if (currentFiber->isRope()) { |
| JSRopeString* currentFiberAsRope = static_cast<JSRopeString*>(currentFiber); |
| for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->m_fibers[i]; ++i) |
| workQueue.append(currentFiberAsRope->m_fibers[i].get()); |
| continue; |
| } |
| |
| StringImpl* string = static_cast<StringImpl*>(currentFiber->m_value.impl()); |
| unsigned length = string->length(); |
| position -= length; |
| StringImpl::copyChars(position, string->characters8(), length); |
| } |
| |
| ASSERT(buffer == position); |
| ASSERT(!isRope()); |
| } |
| |
| void JSRopeString::resolveRopeSlowCase(UChar* buffer) const |
| { |
| UChar* position = buffer + m_length; // We will be working backwards over the rope. |
| Vector<JSString*, 32> workQueue; // These strings are kept alive by the parent rope, so using a Vector is OK. |
| |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) |
| workQueue.append(m_fibers[i].get()); |
| |
| while (!workQueue.isEmpty()) { |
| JSString* currentFiber = workQueue.last(); |
| workQueue.removeLast(); |
| |
| if (currentFiber->isRope()) { |
| JSRopeString* currentFiberAsRope = static_cast<JSRopeString*>(currentFiber); |
| for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->m_fibers[i]; ++i) |
| workQueue.append(currentFiberAsRope->m_fibers[i].get()); |
| continue; |
| } |
| |
| StringImpl* string = static_cast<StringImpl*>(currentFiber->m_value.impl()); |
| unsigned length = string->length(); |
| position -= length; |
| if (string->is8Bit()) |
| StringImpl::copyChars(position, string->characters8(), length); |
| else |
| StringImpl::copyChars(position, string->characters16(), length); |
| } |
| |
| ASSERT(buffer == position); |
| ASSERT(!isRope()); |
| } |
| |
| void JSRopeString::outOfMemory(ExecState* exec) const |
| { |
| for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) |
| m_fibers[i].clear(); |
| ASSERT(isRope()); |
| ASSERT(m_value.isNull()); |
| if (exec) |
| throwOutOfMemoryError(exec); |
| } |
| |
| JSString* JSRopeString::getIndexSlowCase(ExecState* exec, unsigned i) |
| { |
| ASSERT(isRope()); |
| resolveRope(exec); |
| // Return a safe no-value result, this should never be used, since the excetion will be thrown. |
| if (exec->exception()) |
| return jsEmptyString(exec); |
| ASSERT(!isRope()); |
| ASSERT(i < m_value.length()); |
| return jsSingleCharacterSubstring(exec, m_value, i); |
| } |
| |
| JSValue JSString::toPrimitive(ExecState*, PreferredPrimitiveType) const |
| { |
| return const_cast<JSString*>(this); |
| } |
| |
| bool JSString::getPrimitiveNumber(ExecState* exec, double& number, JSValue& result) const |
| { |
| result = this; |
| number = jsToNumber(value(exec)); |
| return false; |
| } |
| |
| bool JSString::toBoolean() const |
| { |
| return m_length; |
| } |
| |
| double JSString::toNumber(ExecState* exec) const |
| { |
| return jsToNumber(value(exec)); |
| } |
| |
| inline StringObject* StringObject::create(ExecState* exec, JSGlobalObject* globalObject, JSString* string) |
| { |
| StringObject* object = new (NotNull, allocateCell<StringObject>(*exec->heap())) StringObject(exec->globalData(), globalObject->stringObjectStructure()); |
| object->finishCreation(exec->globalData(), string); |
| return object; |
| } |
| |
| JSObject* JSString::toObject(ExecState* exec, JSGlobalObject* globalObject) const |
| { |
| return StringObject::create(exec, globalObject, const_cast<JSString*>(this)); |
| } |
| |
| JSObject* JSString::toThisObject(JSCell* cell, ExecState* exec) |
| { |
| return StringObject::create(exec, exec->lexicalGlobalObject(), jsCast<JSString*>(cell)); |
| } |
| |
| bool JSString::getOwnPropertySlot(JSCell* cell, ExecState* exec, PropertyName propertyName, PropertySlot& slot) |
| { |
| JSString* thisObject = jsCast<JSString*>(cell); |
| // The semantics here are really getPropertySlot, not getOwnPropertySlot. |
| // This function should only be called by JSValue::get. |
| if (thisObject->getStringPropertySlot(exec, propertyName, slot)) |
| return true; |
| slot.setBase(thisObject); |
| JSObject* object; |
| for (JSValue prototype = exec->lexicalGlobalObject()->stringPrototype(); !prototype.isNull(); prototype = object->prototype()) { |
| object = asObject(prototype); |
| if (object->methodTable()->getOwnPropertySlot(object, exec, propertyName, slot)) |
| return true; |
| } |
| slot.setUndefined(); |
| return true; |
| } |
| |
| bool JSString::getStringPropertyDescriptor(ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor) |
| { |
| if (propertyName == exec->propertyNames().length) { |
| descriptor.setDescriptor(jsNumber(m_length), DontEnum | DontDelete | ReadOnly); |
| return true; |
| } |
| |
| unsigned i = propertyName.asIndex(); |
| if (i < m_length) { |
| ASSERT(i != PropertyName::NotAnIndex); // No need for an explicit check, the above test would always fail! |
| descriptor.setDescriptor(getIndex(exec, i), DontDelete | ReadOnly); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| bool JSString::getOwnPropertySlotByIndex(JSCell* cell, ExecState* exec, unsigned propertyName, PropertySlot& slot) |
| { |
| JSString* thisObject = jsCast<JSString*>(cell); |
| // The semantics here are really getPropertySlot, not getOwnPropertySlot. |
| // This function should only be called by JSValue::get. |
| if (thisObject->getStringPropertySlot(exec, propertyName, slot)) |
| return true; |
| return JSString::getOwnPropertySlot(thisObject, exec, Identifier::from(exec, propertyName), slot); |
| } |
| |
| } // namespace JSC |