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// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef V8_API_H_
#define V8_API_H_
#include "v8.h"
#include "../include/v8-testing.h"
#include "apiutils.h"
#include "contexts.h"
#include "factory.h"
#include "isolate.h"
#include "list-inl.h"
namespace v8 {
// Constants used in the implementation of the API. The most natural thing
// would usually be to place these with the classes that use them, but
// we want to keep them out of v8.h because it is an externally
// visible file.
class Consts {
public:
enum TemplateType {
FUNCTION_TEMPLATE = 0,
OBJECT_TEMPLATE = 1
};
};
// Utilities for working with neander-objects, primitive
// env-independent JSObjects used by the api.
class NeanderObject {
public:
explicit NeanderObject(int size);
explicit inline NeanderObject(v8::internal::Handle<v8::internal::Object> obj);
explicit inline NeanderObject(v8::internal::Object* obj);
inline v8::internal::Object* get(int index);
inline void set(int index, v8::internal::Object* value);
inline v8::internal::Handle<v8::internal::JSObject> value() { return value_; }
int size();
private:
v8::internal::Handle<v8::internal::JSObject> value_;
};
// Utilities for working with neander-arrays, a simple extensible
// array abstraction built on neander-objects.
class NeanderArray {
public:
NeanderArray();
explicit inline NeanderArray(v8::internal::Handle<v8::internal::Object> obj);
inline v8::internal::Handle<v8::internal::JSObject> value() {
return obj_.value();
}
void add(v8::internal::Handle<v8::internal::Object> value);
int length();
v8::internal::Object* get(int index);
// Change the value at an index to undefined value. If the index is
// out of bounds, the request is ignored. Returns the old value.
void set(int index, v8::internal::Object* value);
private:
NeanderObject obj_;
};
NeanderObject::NeanderObject(v8::internal::Handle<v8::internal::Object> obj)
: value_(v8::internal::Handle<v8::internal::JSObject>::cast(obj)) { }
NeanderObject::NeanderObject(v8::internal::Object* obj)
: value_(v8::internal::Handle<v8::internal::JSObject>(
v8::internal::JSObject::cast(obj))) { }
NeanderArray::NeanderArray(v8::internal::Handle<v8::internal::Object> obj)
: obj_(obj) { }
v8::internal::Object* NeanderObject::get(int offset) {
ASSERT(value()->HasFastObjectElements());
return v8::internal::FixedArray::cast(value()->elements())->get(offset);
}
void NeanderObject::set(int offset, v8::internal::Object* value) {
ASSERT(value_->HasFastObjectElements());
v8::internal::FixedArray::cast(value_->elements())->set(offset, value);
}
template <typename T> inline T ToCData(v8::internal::Object* obj) {
STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
return reinterpret_cast<T>(
reinterpret_cast<intptr_t>(
v8::internal::Foreign::cast(obj)->foreign_address()));
}
template <typename T>
inline v8::internal::Handle<v8::internal::Object> FromCData(T obj) {
STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
return FACTORY->NewForeign(
reinterpret_cast<v8::internal::Address>(reinterpret_cast<intptr_t>(obj)));
}
class ApiFunction {
public:
explicit ApiFunction(v8::internal::Address addr) : addr_(addr) { }
v8::internal::Address address() { return addr_; }
private:
v8::internal::Address addr_;
};
class RegisteredExtension {
public:
explicit RegisteredExtension(Extension* extension);
static void Register(RegisteredExtension* that);
static void UnregisterAll();
Extension* extension() { return extension_; }
RegisteredExtension* next() { return next_; }
RegisteredExtension* next_auto() { return next_auto_; }
static RegisteredExtension* first_extension() { return first_extension_; }
private:
Extension* extension_;
RegisteredExtension* next_;
RegisteredExtension* next_auto_;
static RegisteredExtension* first_extension_;
};
class Utils {
public:
static bool ReportApiFailure(const char* location, const char* message);
static Local<FunctionTemplate> ToFunctionTemplate(NeanderObject obj);
static Local<ObjectTemplate> ToObjectTemplate(NeanderObject obj);
static inline Local<Context> ToLocal(
v8::internal::Handle<v8::internal::Context> obj);
static inline Local<Value> ToLocal(
v8::internal::Handle<v8::internal::Object> obj);
static inline Local<Function> ToLocal(
v8::internal::Handle<v8::internal::JSFunction> obj);
static inline Local<String> ToLocal(
v8::internal::Handle<v8::internal::String> obj);
static inline Local<RegExp> ToLocal(
v8::internal::Handle<v8::internal::JSRegExp> obj);
static inline Local<Object> ToLocal(
v8::internal::Handle<v8::internal::JSObject> obj);
static inline Local<Array> ToLocal(
v8::internal::Handle<v8::internal::JSArray> obj);
static inline Local<External> ToLocal(
v8::internal::Handle<v8::internal::Foreign> obj);
static inline Local<Message> MessageToLocal(
v8::internal::Handle<v8::internal::Object> obj);
static inline Local<StackTrace> StackTraceToLocal(
v8::internal::Handle<v8::internal::JSArray> obj);
static inline Local<StackFrame> StackFrameToLocal(
v8::internal::Handle<v8::internal::JSObject> obj);
static inline Local<Number> NumberToLocal(
v8::internal::Handle<v8::internal::Object> obj);
static inline Local<Integer> IntegerToLocal(
v8::internal::Handle<v8::internal::Object> obj);
static inline Local<Uint32> Uint32ToLocal(
v8::internal::Handle<v8::internal::Object> obj);
static inline Local<FunctionTemplate> ToLocal(
v8::internal::Handle<v8::internal::FunctionTemplateInfo> obj);
static inline Local<ObjectTemplate> ToLocal(
v8::internal::Handle<v8::internal::ObjectTemplateInfo> obj);
static inline Local<Signature> ToLocal(
v8::internal::Handle<v8::internal::SignatureInfo> obj);
static inline Local<AccessorSignature> AccessorSignatureToLocal(
v8::internal::Handle<v8::internal::FunctionTemplateInfo> obj);
static inline Local<TypeSwitch> ToLocal(
v8::internal::Handle<v8::internal::TypeSwitchInfo> obj);
static inline v8::internal::Handle<v8::internal::TemplateInfo>
OpenHandle(const Template* that);
static inline v8::internal::Handle<v8::internal::FunctionTemplateInfo>
OpenHandle(const FunctionTemplate* that);
static inline v8::internal::Handle<v8::internal::ObjectTemplateInfo>
OpenHandle(const ObjectTemplate* that);
static inline v8::internal::Handle<v8::internal::Object>
OpenHandle(const Data* data);
static inline v8::internal::Handle<v8::internal::JSRegExp>
OpenHandle(const RegExp* data);
static inline v8::internal::Handle<v8::internal::JSObject>
OpenHandle(const v8::Object* data);
static inline v8::internal::Handle<v8::internal::JSArray>
OpenHandle(const v8::Array* data);
static inline v8::internal::Handle<v8::internal::String>
OpenHandle(const String* data);
static inline v8::internal::Handle<v8::internal::Object>
OpenHandle(const Script* data);
static inline v8::internal::Handle<v8::internal::JSFunction>
OpenHandle(const Function* data);
static inline v8::internal::Handle<v8::internal::JSObject>
OpenHandle(const Message* message);
static inline v8::internal::Handle<v8::internal::JSArray>
OpenHandle(const StackTrace* stack_trace);
static inline v8::internal::Handle<v8::internal::JSObject>
OpenHandle(const StackFrame* stack_frame);
static inline v8::internal::Handle<v8::internal::Context>
OpenHandle(const v8::Context* context);
static inline v8::internal::Handle<v8::internal::SignatureInfo>
OpenHandle(const v8::Signature* sig);
static inline v8::internal::Handle<v8::internal::FunctionTemplateInfo>
OpenHandle(const v8::AccessorSignature* sig);
static inline v8::internal::Handle<v8::internal::TypeSwitchInfo>
OpenHandle(const v8::TypeSwitch* that);
static inline v8::internal::Handle<v8::internal::Foreign>
OpenHandle(const v8::External* that);
};
template <class T>
inline T* ToApi(v8::internal::Handle<v8::internal::Object> obj) {
return reinterpret_cast<T*>(obj.location());
}
template <class T>
v8::internal::Handle<T> v8::internal::Handle<T>::EscapeFrom(
v8::HandleScope* scope) {
v8::internal::Handle<T> handle;
if (!is_null()) {
handle = *this;
}
return Utils::OpenHandle(*scope->Close(Utils::ToLocal(handle)));
}
// Implementations of ToLocal
#define MAKE_TO_LOCAL(Name, From, To) \
Local<v8::To> Utils::Name(v8::internal::Handle<v8::internal::From> obj) { \
ASSERT(obj.is_null() || !obj->IsTheHole()); \
return Local<To>(reinterpret_cast<To*>(obj.location())); \
}
MAKE_TO_LOCAL(ToLocal, Context, Context)
MAKE_TO_LOCAL(ToLocal, Object, Value)
MAKE_TO_LOCAL(ToLocal, JSFunction, Function)
MAKE_TO_LOCAL(ToLocal, String, String)
MAKE_TO_LOCAL(ToLocal, JSRegExp, RegExp)
MAKE_TO_LOCAL(ToLocal, JSObject, Object)
MAKE_TO_LOCAL(ToLocal, JSArray, Array)
MAKE_TO_LOCAL(ToLocal, Foreign, External)
MAKE_TO_LOCAL(ToLocal, FunctionTemplateInfo, FunctionTemplate)
MAKE_TO_LOCAL(ToLocal, ObjectTemplateInfo, ObjectTemplate)
MAKE_TO_LOCAL(ToLocal, SignatureInfo, Signature)
MAKE_TO_LOCAL(AccessorSignatureToLocal, FunctionTemplateInfo, AccessorSignature)
MAKE_TO_LOCAL(ToLocal, TypeSwitchInfo, TypeSwitch)
MAKE_TO_LOCAL(MessageToLocal, Object, Message)
MAKE_TO_LOCAL(StackTraceToLocal, JSArray, StackTrace)
MAKE_TO_LOCAL(StackFrameToLocal, JSObject, StackFrame)
MAKE_TO_LOCAL(NumberToLocal, Object, Number)
MAKE_TO_LOCAL(IntegerToLocal, Object, Integer)
MAKE_TO_LOCAL(Uint32ToLocal, Object, Uint32)
#undef MAKE_TO_LOCAL
// Implementations of OpenHandle
#define MAKE_OPEN_HANDLE(From, To) \
v8::internal::Handle<v8::internal::To> Utils::OpenHandle(\
const v8::From* that) { \
return v8::internal::Handle<v8::internal::To>( \
reinterpret_cast<v8::internal::To**>(const_cast<v8::From*>(that))); \
}
MAKE_OPEN_HANDLE(Template, TemplateInfo)
MAKE_OPEN_HANDLE(FunctionTemplate, FunctionTemplateInfo)
MAKE_OPEN_HANDLE(ObjectTemplate, ObjectTemplateInfo)
MAKE_OPEN_HANDLE(Signature, SignatureInfo)
MAKE_OPEN_HANDLE(AccessorSignature, FunctionTemplateInfo)
MAKE_OPEN_HANDLE(TypeSwitch, TypeSwitchInfo)
MAKE_OPEN_HANDLE(Data, Object)
MAKE_OPEN_HANDLE(RegExp, JSRegExp)
MAKE_OPEN_HANDLE(Object, JSObject)
MAKE_OPEN_HANDLE(Array, JSArray)
MAKE_OPEN_HANDLE(String, String)
MAKE_OPEN_HANDLE(Script, Object)
MAKE_OPEN_HANDLE(Function, JSFunction)
MAKE_OPEN_HANDLE(Message, JSObject)
MAKE_OPEN_HANDLE(Context, Context)
MAKE_OPEN_HANDLE(External, Foreign)
MAKE_OPEN_HANDLE(StackTrace, JSArray)
MAKE_OPEN_HANDLE(StackFrame, JSObject)
#undef MAKE_OPEN_HANDLE
namespace internal {
// Tracks string usage to help make better decisions when
// externalizing strings.
//
// Implementation note: internally this class only tracks fresh
// strings and keeps a single use counter for them.
class StringTracker {
public:
// Records that the given string's characters were copied to some
// external buffer. If this happens often we should honor
// externalization requests for the string.
void RecordWrite(Handle<String> string) {
Address address = reinterpret_cast<Address>(*string);
Address top = isolate_->heap()->NewSpaceTop();
if (IsFreshString(address, top)) {
IncrementUseCount(top);
}
}
// Estimates freshness and use frequency of the given string based
// on how close it is to the new space top and the recorded usage
// history.
inline bool IsFreshUnusedString(Handle<String> string) {
Address address = reinterpret_cast<Address>(*string);
Address top = isolate_->heap()->NewSpaceTop();
return IsFreshString(address, top) && IsUseCountLow(top);
}
private:
StringTracker() : use_count_(0), last_top_(NULL), isolate_(NULL) { }
static inline bool IsFreshString(Address string, Address top) {
return top - kFreshnessLimit <= string && string <= top;
}
inline bool IsUseCountLow(Address top) {
if (last_top_ != top) return true;
return use_count_ < kUseLimit;
}
inline void IncrementUseCount(Address top) {
if (last_top_ != top) {
use_count_ = 0;
last_top_ = top;
}
++use_count_;
}
// Single use counter shared by all fresh strings.
int use_count_;
// Last new space top when the use count above was valid.
Address last_top_;
Isolate* isolate_;
// How close to the new space top a fresh string has to be.
static const int kFreshnessLimit = 1024;
// The number of uses required to consider a string useful.
static const int kUseLimit = 32;
friend class Isolate;
DISALLOW_COPY_AND_ASSIGN(StringTracker);
};
class DeferredHandles {
public:
~DeferredHandles();
private:
DeferredHandles(DeferredHandles* next, Object** first_block_limit,
HandleScopeImplementer* impl)
: next_(next),
previous_(NULL),
first_block_limit_(first_block_limit),
impl_(impl) {
if (next != NULL) next->previous_ = this;
}
void Iterate(ObjectVisitor* v);
List<Object**> blocks_;
DeferredHandles* next_;
DeferredHandles* previous_;
Object** first_block_limit_;
HandleScopeImplementer* impl_;
friend class HandleScopeImplementer;
};
// This class is here in order to be able to declare it a friend of
// HandleScope. Moving these methods to be members of HandleScope would be
// neat in some ways, but it would expose internal implementation details in
// our public header file, which is undesirable.
//
// An isolate has a single instance of this class to hold the current thread's
// data. In multithreaded V8 programs this data is copied in and out of storage
// so that the currently executing thread always has its own copy of this
// data.
class HandleScopeImplementer {
public:
explicit HandleScopeImplementer(Isolate* isolate)
: isolate_(isolate),
blocks_(0),
entered_contexts_(0),
saved_contexts_(0),
spare_(NULL),
call_depth_(0),
last_handle_before_deferred_block_(NULL),
deferred_handles_head_(NULL) { }
~HandleScopeImplementer() {
DeleteArray(spare_);
}
// Threading support for handle data.
static int ArchiveSpacePerThread();
char* RestoreThread(char* from);
char* ArchiveThread(char* to);
void FreeThreadResources();
// Garbage collection support.
void Iterate(v8::internal::ObjectVisitor* v);
static char* Iterate(v8::internal::ObjectVisitor* v, char* data);
inline internal::Object** GetSpareOrNewBlock();
inline void DeleteExtensions(internal::Object** prev_limit);
inline void IncrementCallDepth() {call_depth_++;}
inline void DecrementCallDepth() {call_depth_--;}
inline bool CallDepthIsZero() { return call_depth_ == 0; }
inline void EnterContext(Handle<Object> context);
inline bool LeaveLastContext();
// Returns the last entered context or an empty handle if no
// contexts have been entered.
inline Handle<Object> LastEnteredContext();
inline void SaveContext(Context* context);
inline Context* RestoreContext();
inline bool HasSavedContexts();
inline List<internal::Object**>* blocks() { return &blocks_; }
Isolate* isolate() const { return isolate_; }
private:
void ResetAfterArchive() {
blocks_.Initialize(0);
entered_contexts_.Initialize(0);
saved_contexts_.Initialize(0);
spare_ = NULL;
deferred_handles_head_ = NULL;
last_handle_before_deferred_block_ = NULL;
call_depth_ = 0;
}
void Free() {
ASSERT(blocks_.length() == 0);
ASSERT(entered_contexts_.length() == 0);
ASSERT(saved_contexts_.length() == 0);
ASSERT(deferred_handles_head_ == NULL);
blocks_.Free();
entered_contexts_.Free();
saved_contexts_.Free();
if (spare_ != NULL) {
DeleteArray(spare_);
spare_ = NULL;
}
ASSERT(call_depth_ == 0);
}
void BeginDeferredScope();
DeferredHandles* Detach(Object** prev_limit);
void DestroyDeferredHandles(DeferredHandles* handles);
Isolate* isolate_;
List<internal::Object**> blocks_;
// Used as a stack to keep track of entered contexts.
List<Handle<Object> > entered_contexts_;
// Used as a stack to keep track of saved contexts.
List<Context*> saved_contexts_;
Object** spare_;
int call_depth_;
Object** last_handle_before_deferred_block_;
DeferredHandles* deferred_handles_head_;
// This is only used for threading support.
v8::ImplementationUtilities::HandleScopeData handle_scope_data_;
void IterateThis(ObjectVisitor* v);
char* RestoreThreadHelper(char* from);
char* ArchiveThreadHelper(char* to);
friend class DeferredHandles;
friend class DeferredHandleScope;
DISALLOW_COPY_AND_ASSIGN(HandleScopeImplementer);
};
const int kHandleBlockSize = v8::internal::KB - 2; // fit in one page
void HandleScopeImplementer::SaveContext(Context* context) {
saved_contexts_.Add(context);
}
Context* HandleScopeImplementer::RestoreContext() {
return saved_contexts_.RemoveLast();
}
bool HandleScopeImplementer::HasSavedContexts() {
return !saved_contexts_.is_empty();
}
void HandleScopeImplementer::EnterContext(Handle<Object> context) {
entered_contexts_.Add(context);
}
bool HandleScopeImplementer::LeaveLastContext() {
if (entered_contexts_.is_empty()) return false;
entered_contexts_.RemoveLast();
return true;
}
Handle<Object> HandleScopeImplementer::LastEnteredContext() {
if (entered_contexts_.is_empty()) return Handle<Object>::null();
return entered_contexts_.last();
}
// If there's a spare block, use it for growing the current scope.
internal::Object** HandleScopeImplementer::GetSpareOrNewBlock() {
internal::Object** block = (spare_ != NULL) ?
spare_ :
NewArray<internal::Object*>(kHandleBlockSize);
spare_ = NULL;
return block;
}
void HandleScopeImplementer::DeleteExtensions(internal::Object** prev_limit) {
while (!blocks_.is_empty()) {
internal::Object** block_start = blocks_.last();
internal::Object** block_limit = block_start + kHandleBlockSize;
#ifdef DEBUG
// NoHandleAllocation may make the prev_limit to point inside the block.
if (block_start <= prev_limit && prev_limit <= block_limit) break;
#else
if (prev_limit == block_limit) break;
#endif
blocks_.RemoveLast();
#ifdef DEBUG
v8::ImplementationUtilities::ZapHandleRange(block_start, block_limit);
#endif
if (spare_ != NULL) {
DeleteArray(spare_);
}
spare_ = block_start;
}
ASSERT((blocks_.is_empty() && prev_limit == NULL) ||
(!blocks_.is_empty() && prev_limit != NULL));
}
class Testing {
public:
static v8::Testing::StressType stress_type() { return stress_type_; }
static void set_stress_type(v8::Testing::StressType stress_type) {
stress_type_ = stress_type;
}
private:
static v8::Testing::StressType stress_type_;
};
} } // namespace v8::internal
#endif // V8_API_H_