/*
* Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
* Copyright (C) 2003, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifndef Lookup_h
#define Lookup_h
#include "CallFrame.h"
#include "Identifier.h"
#include "JSGlobalObject.h"
#include "JSObject.h"
#include "PropertySlot.h"
#include <stdio.h>
#include <wtf/Assertions.h>
// Bug #26843: Work around Metrowerks compiler bug
#if COMPILER(WINSCW)
#define JSC_CONST_HASHTABLE
#else
#define JSC_CONST_HASHTABLE const
#endif
namespace JSC {
// Hash table generated by the create_hash_table script.
struct HashTableValue {
const char* key; // property name
unsigned char attributes; // JSObject attributes
intptr_t value1;
intptr_t value2;
};
// FIXME: There is no reason this get function can't be simpler.
// ie. typedef JSValue (*GetFunction)(ExecState*, JSObject* baseObject)
typedef PropertySlot::GetValueFunc GetFunction;
typedef void (*PutFunction)(ExecState*, JSObject* baseObject, JSValue value);
class HashEntry : public FastAllocBase {
public:
void initialize(UString::Rep* key, unsigned char attributes, intptr_t v1, intptr_t v2)
{
m_key = key;
m_attributes = attributes;
m_u.store.value1 = v1;
m_u.store.value2 = v2;
m_next = 0;
}
void setKey(UString::Rep* key) { m_key = key; }
UString::Rep* key() const { return m_key; }
unsigned char attributes() const { return m_attributes; }
NativeFunction function() const { ASSERT(m_attributes & Function); return m_u.function.functionValue; }
unsigned char functionLength() const { ASSERT(m_attributes & Function); return static_cast<unsigned char>(m_u.function.length); }
GetFunction propertyGetter() const { ASSERT(!(m_attributes & Function)); return m_u.property.get; }
PutFunction propertyPutter() const { ASSERT(!(m_attributes & Function)); return m_u.property.put; }
intptr_t lexerValue() const { ASSERT(!m_attributes); return m_u.lexer.value; }
void setNext(HashEntry *next) { m_next = next; }
HashEntry* next() const { return m_next; }
private:
UString::Rep* m_key;
unsigned char m_attributes; // JSObject attributes
union {
struct {
intptr_t value1;
intptr_t value2;
} store;
struct {
NativeFunction functionValue;
intptr_t length; // number of arguments for function
} function;
struct {
GetFunction get;
PutFunction put;
} property;
struct {
intptr_t value;
intptr_t unused;
} lexer;
} m_u;
HashEntry* m_next;
};
struct HashTable {
int compactSize;
int compactHashSizeMask;
const HashTableValue* values; // Fixed values generated by script.
mutable const HashEntry* table; // Table allocated at runtime.
ALWAYS_INLINE void initializeIfNeeded(JSGlobalData* globalData) const
{
if (!table)
createTable(globalData);
}
ALWAYS_INLINE void initializeIfNeeded(ExecState* exec) const
{
if (!table)
createTable(&exec->globalData());
}
void deleteTable() const;
// Find an entry in the table, and return the entry.
ALWAYS_INLINE const HashEntry* entry(JSGlobalData* globalData, const Identifier& identifier) const
{
initializeIfNeeded(globalData);
return entry(identifier);
}
ALWAYS_INLINE const HashEntry* entry(ExecState* exec, const Identifier& identifier) const
{
initializeIfNeeded(exec);
return entry(identifier);
}
private:
ALWAYS_INLINE const HashEntry* entry(const Identifier& identifier) const
{
ASSERT(table);
const HashEntry* entry = &table[identifier.ustring().rep()->existingHash() & compactHashSizeMask];
if (!entry->key())
return 0;
do {
if (entry->key() == identifier.ustring().rep())
return entry;
entry = entry->next();
} while (entry);
return 0;
}
// Convert the hash table keys to identifiers.
void createTable(JSGlobalData*) const;
};
void setUpStaticFunctionSlot(ExecState*, const HashEntry*, JSObject* thisObject, const Identifier& propertyName, PropertySlot&);
/**
* This method does it all (looking in the hashtable, checking for function
* overrides, creating the function or retrieving from cache, calling
* getValueProperty in case of a non-function property, forwarding to parent if
* unknown property).
*/
template <class ThisImp, class ParentImp>
inline bool getStaticPropertySlot(ExecState* exec, const HashTable* table, ThisImp* thisObj, const Identifier& propertyName, PropertySlot& slot)
{
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry) // not found, forward to parent
return thisObj->ParentImp::getOwnPropertySlot(exec, propertyName, slot);
if (entry->attributes() & Function)
setUpStaticFunctionSlot(exec, entry, thisObj, propertyName, slot);
else
slot.setCustom(thisObj, entry->propertyGetter());
return true;
}
template <class ThisImp, class ParentImp>
inline bool getStaticPropertyDescriptor(ExecState* exec, const HashTable* table, ThisImp* thisObj, const Identifier& propertyName, PropertyDescriptor& descriptor)
{
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry) // not found, forward to parent
return thisObj->ParentImp::getOwnPropertyDescriptor(exec, propertyName, descriptor);
PropertySlot slot;
if (entry->attributes() & Function)
setUpStaticFunctionSlot(exec, entry, thisObj, propertyName, slot);
else
slot.setCustom(thisObj, entry->propertyGetter());
descriptor.setDescriptor(slot.getValue(exec, propertyName), entry->attributes());
return true;
}
/**
* Simplified version of getStaticPropertySlot in case there are only functions.
* Using this instead of getStaticPropertySlot allows 'this' to avoid implementing
* a dummy getValueProperty.
*/
template <class ParentImp>
inline bool getStaticFunctionSlot(ExecState* exec, const HashTable* table, JSObject* thisObj, const Identifier& propertyName, PropertySlot& slot)
{
if (static_cast<ParentImp*>(thisObj)->ParentImp::getOwnPropertySlot(exec, propertyName, slot))
return true;
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry)
return false;
setUpStaticFunctionSlot(exec, entry, thisObj, propertyName, slot);
return true;
}
/**
* Simplified version of getStaticPropertyDescriptor in case there are only functions.
* Using this instead of getStaticPropertyDescriptor allows 'this' to avoid implementing
* a dummy getValueProperty.
*/
template <class ParentImp>
inline bool getStaticFunctionDescriptor(ExecState* exec, const HashTable* table, JSObject* thisObj, const Identifier& propertyName, PropertyDescriptor& descriptor)
{
if (static_cast<ParentImp*>(thisObj)->ParentImp::getOwnPropertyDescriptor(exec, propertyName, descriptor))
return true;
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry)
return false;
PropertySlot slot;
setUpStaticFunctionSlot(exec, entry, thisObj, propertyName, slot);
descriptor.setDescriptor(slot.getValue(exec, propertyName), entry->attributes());
return true;
}
/**
* Simplified version of getStaticPropertySlot in case there are no functions, only "values".
* Using this instead of getStaticPropertySlot removes the need for a FuncImp class.
*/
template <class ThisImp, class ParentImp>
inline bool getStaticValueSlot(ExecState* exec, const HashTable* table, ThisImp* thisObj, const Identifier& propertyName, PropertySlot& slot)
{
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry) // not found, forward to parent
return thisObj->ParentImp::getOwnPropertySlot(exec, propertyName, slot);
ASSERT(!(entry->attributes() & Function));
slot.setCustom(thisObj, entry->propertyGetter());
return true;
}
/**
* Simplified version of getStaticPropertyDescriptor in case there are no functions, only "values".
* Using this instead of getStaticPropertyDescriptor removes the need for a FuncImp class.
*/
template <class ThisImp, class ParentImp>
inline bool getStaticValueDescriptor(ExecState* exec, const HashTable* table, ThisImp* thisObj, const Identifier& propertyName, PropertyDescriptor& descriptor)
{
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry) // not found, forward to parent
return thisObj->ParentImp::getOwnPropertyDescriptor(exec, propertyName, descriptor);
ASSERT(!(entry->attributes() & Function));
PropertySlot slot;
slot.setCustom(thisObj, entry->propertyGetter());
descriptor.setDescriptor(slot.getValue(exec, propertyName), entry->attributes());
return true;
}
/**
* This one is for "put".
* It looks up a hash entry for the property to be set. If an entry
* is found it sets the value and returns true, else it returns false.
*/
template <class ThisImp>
inline bool lookupPut(ExecState* exec, const Identifier& propertyName, JSValue value, const HashTable* table, ThisImp* thisObj)
{
const HashEntry* entry = table->entry(exec, propertyName);
if (!entry)
return false;
if (entry->attributes() & Function) { // function: put as override property
if (LIKELY(value.isCell()))
thisObj->putDirectFunction(propertyName, value.asCell());
else
thisObj->putDirect(propertyName, value);
} else if (!(entry->attributes() & ReadOnly))
entry->propertyPutter()(exec, thisObj, value);
return true;
}
/**
* This one is for "put".
* It calls lookupPut<ThisImp>() to set the value. If that call
* returns false (meaning no entry in the hash table was found),
* then it calls put() on the ParentImp class.
*/
template <class ThisImp, class ParentImp>
inline void lookupPut(ExecState* exec, const Identifier& propertyName, JSValue value, const HashTable* table, ThisImp* thisObj, PutPropertySlot& slot)
{
if (!lookupPut<ThisImp>(exec, propertyName, value, table, thisObj))
thisObj->ParentImp::put(exec, propertyName, value, slot); // not found: forward to parent
}
} // namespace JSC
#endif // Lookup_h