api.h revision 5913587db4c6bab03d97bfe44b06289fd6d7270d 
1// Copyright 2008 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28#ifndef V8_API_H_
29#define V8_API_H_
30
31#include "apiutils.h"
32#include "factory.h"
33
34namespace v8 {
35
36// Constants used in the implementation of the API.  The most natural thing
37// would usually be to place these with the classes that use them, but
38// we want to keep them out of v8.h because it is an externally
39// visible file.
40class Consts {
41 public:
42  enum TemplateType {
43    FUNCTION_TEMPLATE = 0,
44    OBJECT_TEMPLATE = 1
45  };
46};
47
48
49// Utilities for working with neander-objects, primitive
50// env-independent JSObjects used by the api.
51class NeanderObject {
52 public:
53  explicit NeanderObject(int size);
54  inline NeanderObject(v8::internal::Handle<v8::internal::Object> obj);
55  inline NeanderObject(v8::internal::Object* obj);
56  inline v8::internal::Object* get(int index);
57  inline void set(int index, v8::internal::Object* value);
58  inline v8::internal::Handle<v8::internal::JSObject> value() { return value_; }
59  int size();
60 private:
61  v8::internal::Handle<v8::internal::JSObject> value_;
62};
63
64
65// Utilities for working with neander-arrays, a simple extensible
66// array abstraction built on neander-objects.
67class NeanderArray {
68 public:
69  NeanderArray();
70  inline NeanderArray(v8::internal::Handle<v8::internal::Object> obj);
71  inline v8::internal::Handle<v8::internal::JSObject> value() {
72    return obj_.value();
73  }
74
75  void add(v8::internal::Handle<v8::internal::Object> value);
76
77  int length();
78
79  v8::internal::Object* get(int index);
80  // Change the value at an index to undefined value. If the index is
81  // out of bounds, the request is ignored. Returns the old value.
82  void set(int index, v8::internal::Object* value);
83 private:
84  NeanderObject obj_;
85};
86
87
88NeanderObject::NeanderObject(v8::internal::Handle<v8::internal::Object> obj)
89    : value_(v8::internal::Handle<v8::internal::JSObject>::cast(obj)) { }
90
91
92NeanderObject::NeanderObject(v8::internal::Object* obj)
93    : value_(v8::internal::Handle<v8::internal::JSObject>(
94        v8::internal::JSObject::cast(obj))) { }
95
96
97NeanderArray::NeanderArray(v8::internal::Handle<v8::internal::Object> obj)
98    : obj_(obj) { }
99
100
101v8::internal::Object* NeanderObject::get(int offset) {
102  ASSERT(value()->HasFastElements());
103  return v8::internal::FixedArray::cast(value()->elements())->get(offset);
104}
105
106
107void NeanderObject::set(int offset, v8::internal::Object* value) {
108  ASSERT(value_->HasFastElements());
109  v8::internal::FixedArray::cast(value_->elements())->set(offset, value);
110}
111
112
113template <typename T> static inline T ToCData(v8::internal::Object* obj) {
114  STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
115  return reinterpret_cast<T>(
116      reinterpret_cast<intptr_t>(v8::internal::Proxy::cast(obj)->proxy()));
117}
118
119
120template <typename T>
121static inline v8::internal::Handle<v8::internal::Object> FromCData(T obj) {
122  STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
123  return v8::internal::Factory::NewProxy(
124      reinterpret_cast<v8::internal::Address>(reinterpret_cast<intptr_t>(obj)));
125}
126
127
128class ApiFunction {
129 public:
130  explicit ApiFunction(v8::internal::Address addr) : addr_(addr) { }
131  v8::internal::Address address() { return addr_; }
132 private:
133  v8::internal::Address addr_;
134};
135
136
137enum ExtensionTraversalState {
138  UNVISITED, VISITED, INSTALLED
139};
140
141
142class RegisteredExtension {
143 public:
144  explicit RegisteredExtension(Extension* extension);
145  static void Register(RegisteredExtension* that);
146  Extension* extension() { return extension_; }
147  RegisteredExtension* next() { return next_; }
148  RegisteredExtension* next_auto() { return next_auto_; }
149  ExtensionTraversalState state() { return state_; }
150  void set_state(ExtensionTraversalState value) { state_ = value; }
151  static RegisteredExtension* first_extension() { return first_extension_; }
152 private:
153  Extension* extension_;
154  RegisteredExtension* next_;
155  RegisteredExtension* next_auto_;
156  ExtensionTraversalState state_;
157  static RegisteredExtension* first_extension_;
158  static RegisteredExtension* first_auto_extension_;
159};
160
161
162class Utils {
163 public:
164  static bool ReportApiFailure(const char* location, const char* message);
165
166  static Local<FunctionTemplate> ToFunctionTemplate(NeanderObject obj);
167  static Local<ObjectTemplate> ToObjectTemplate(NeanderObject obj);
168
169  static inline Local<Context> ToLocal(
170      v8::internal::Handle<v8::internal::Context> obj);
171  static inline Local<Value> ToLocal(
172      v8::internal::Handle<v8::internal::Object> obj);
173  static inline Local<Function> ToLocal(
174      v8::internal::Handle<v8::internal::JSFunction> obj);
175  static inline Local<String> ToLocal(
176      v8::internal::Handle<v8::internal::String> obj);
177  static inline Local<RegExp> ToLocal(
178      v8::internal::Handle<v8::internal::JSRegExp> obj);
179  static inline Local<Object> ToLocal(
180      v8::internal::Handle<v8::internal::JSObject> obj);
181  static inline Local<Array> ToLocal(
182      v8::internal::Handle<v8::internal::JSArray> obj);
183  static inline Local<External> ToLocal(
184      v8::internal::Handle<v8::internal::Proxy> obj);
185  static inline Local<Message> MessageToLocal(
186      v8::internal::Handle<v8::internal::Object> obj);
187  static inline Local<StackTrace> StackTraceToLocal(
188      v8::internal::Handle<v8::internal::JSArray> obj);
189  static inline Local<StackFrame> StackFrameToLocal(
190      v8::internal::Handle<v8::internal::JSObject> obj);
191  static inline Local<Number> NumberToLocal(
192      v8::internal::Handle<v8::internal::Object> obj);
193  static inline Local<Integer> IntegerToLocal(
194      v8::internal::Handle<v8::internal::Object> obj);
195  static inline Local<Uint32> Uint32ToLocal(
196      v8::internal::Handle<v8::internal::Object> obj);
197  static inline Local<FunctionTemplate> ToLocal(
198      v8::internal::Handle<v8::internal::FunctionTemplateInfo> obj);
199  static inline Local<ObjectTemplate> ToLocal(
200      v8::internal::Handle<v8::internal::ObjectTemplateInfo> obj);
201  static inline Local<Signature> ToLocal(
202      v8::internal::Handle<v8::internal::SignatureInfo> obj);
203  static inline Local<TypeSwitch> ToLocal(
204      v8::internal::Handle<v8::internal::TypeSwitchInfo> obj);
205
206  static inline v8::internal::Handle<v8::internal::TemplateInfo>
207      OpenHandle(const Template* that);
208  static inline v8::internal::Handle<v8::internal::FunctionTemplateInfo>
209      OpenHandle(const FunctionTemplate* that);
210  static inline v8::internal::Handle<v8::internal::ObjectTemplateInfo>
211      OpenHandle(const ObjectTemplate* that);
212  static inline v8::internal::Handle<v8::internal::Object>
213      OpenHandle(const Data* data);
214  static inline v8::internal::Handle<v8::internal::JSRegExp>
215      OpenHandle(const RegExp* data);
216  static inline v8::internal::Handle<v8::internal::JSObject>
217      OpenHandle(const v8::Object* data);
218  static inline v8::internal::Handle<v8::internal::JSArray>
219      OpenHandle(const v8::Array* data);
220  static inline v8::internal::Handle<v8::internal::String>
221      OpenHandle(const String* data);
222  static inline v8::internal::Handle<v8::internal::Object>
223      OpenHandle(const Script* data);
224  static inline v8::internal::Handle<v8::internal::JSFunction>
225      OpenHandle(const Function* data);
226  static inline v8::internal::Handle<v8::internal::JSObject>
227      OpenHandle(const Message* message);
228  static inline v8::internal::Handle<v8::internal::JSArray>
229      OpenHandle(const StackTrace* stack_trace);
230  static inline v8::internal::Handle<v8::internal::JSObject>
231      OpenHandle(const StackFrame* stack_frame);
232  static inline v8::internal::Handle<v8::internal::Context>
233      OpenHandle(const v8::Context* context);
234  static inline v8::internal::Handle<v8::internal::SignatureInfo>
235      OpenHandle(const v8::Signature* sig);
236  static inline v8::internal::Handle<v8::internal::TypeSwitchInfo>
237      OpenHandle(const v8::TypeSwitch* that);
238  static inline v8::internal::Handle<v8::internal::Proxy>
239      OpenHandle(const v8::External* that);
240};
241
242
243template <class T>
244static inline T* ToApi(v8::internal::Handle<v8::internal::Object> obj) {
245  return reinterpret_cast<T*>(obj.location());
246}
247
248
249template <class T>
250v8::internal::Handle<T> v8::internal::Handle<T>::EscapeFrom(
251    v8::HandleScope* scope) {
252  v8::internal::Handle<T> handle;
253  if (!is_null()) {
254    handle = *this;
255  }
256  return Utils::OpenHandle(*scope->Close(Utils::ToLocal(handle)));
257}
258
259
260// Implementations of ToLocal
261
262#define MAKE_TO_LOCAL(Name, From, To)                                       \
263  Local<v8::To> Utils::Name(v8::internal::Handle<v8::internal::From> obj) { \
264    ASSERT(obj.is_null() || !obj->IsTheHole());                             \
265    return Local<To>(reinterpret_cast<To*>(obj.location()));                \
266  }
267
268MAKE_TO_LOCAL(ToLocal, Context, Context)
269MAKE_TO_LOCAL(ToLocal, Object, Value)
270MAKE_TO_LOCAL(ToLocal, JSFunction, Function)
271MAKE_TO_LOCAL(ToLocal, String, String)
272MAKE_TO_LOCAL(ToLocal, JSRegExp, RegExp)
273MAKE_TO_LOCAL(ToLocal, JSObject, Object)
274MAKE_TO_LOCAL(ToLocal, JSArray, Array)
275MAKE_TO_LOCAL(ToLocal, Proxy, External)
276MAKE_TO_LOCAL(ToLocal, FunctionTemplateInfo, FunctionTemplate)
277MAKE_TO_LOCAL(ToLocal, ObjectTemplateInfo, ObjectTemplate)
278MAKE_TO_LOCAL(ToLocal, SignatureInfo, Signature)
279MAKE_TO_LOCAL(ToLocal, TypeSwitchInfo, TypeSwitch)
280MAKE_TO_LOCAL(MessageToLocal, Object, Message)
281MAKE_TO_LOCAL(StackTraceToLocal, JSArray, StackTrace)
282MAKE_TO_LOCAL(StackFrameToLocal, JSObject, StackFrame)
283MAKE_TO_LOCAL(NumberToLocal, Object, Number)
284MAKE_TO_LOCAL(IntegerToLocal, Object, Integer)
285MAKE_TO_LOCAL(Uint32ToLocal, Object, Uint32)
286
287#undef MAKE_TO_LOCAL
288
289
290// Implementations of OpenHandle
291
292#define MAKE_OPEN_HANDLE(From, To) \
293  v8::internal::Handle<v8::internal::To> Utils::OpenHandle(\
294    const v8::From* that) { \
295    return v8::internal::Handle<v8::internal::To>( \
296        reinterpret_cast<v8::internal::To**>(const_cast<v8::From*>(that))); \
297  }
298
299MAKE_OPEN_HANDLE(Template, TemplateInfo)
300MAKE_OPEN_HANDLE(FunctionTemplate, FunctionTemplateInfo)
301MAKE_OPEN_HANDLE(ObjectTemplate, ObjectTemplateInfo)
302MAKE_OPEN_HANDLE(Signature, SignatureInfo)
303MAKE_OPEN_HANDLE(TypeSwitch, TypeSwitchInfo)
304MAKE_OPEN_HANDLE(Data, Object)
305MAKE_OPEN_HANDLE(RegExp, JSRegExp)
306MAKE_OPEN_HANDLE(Object, JSObject)
307MAKE_OPEN_HANDLE(Array, JSArray)
308MAKE_OPEN_HANDLE(String, String)
309MAKE_OPEN_HANDLE(Script, Object)
310MAKE_OPEN_HANDLE(Function, JSFunction)
311MAKE_OPEN_HANDLE(Message, JSObject)
312MAKE_OPEN_HANDLE(Context, Context)
313MAKE_OPEN_HANDLE(External, Proxy)
314MAKE_OPEN_HANDLE(StackTrace, JSArray)
315MAKE_OPEN_HANDLE(StackFrame, JSObject)
316
317#undef MAKE_OPEN_HANDLE
318
319
320namespace internal {
321
322// This class is here in order to be able to declare it a friend of
323// HandleScope.  Moving these methods to be members of HandleScope would be
324// neat in some ways, but it would expose external implementation details in
325// our public header file, which is undesirable.
326//
327// There is a singleton instance of this class to hold the per-thread data.
328// For multithreaded V8 programs this data is copied in and out of storage
329// so that the currently executing thread always has its own copy of this
330// data.
331class HandleScopeImplementer {
332 public:
333
334  HandleScopeImplementer()
335      : blocks_(0),
336        entered_contexts_(0),
337        saved_contexts_(0),
338        spare_(NULL),
339        ignore_out_of_memory_(false),
340        call_depth_(0) { }
341
342  static HandleScopeImplementer* instance();
343
344  // Threading support for handle data.
345  static int ArchiveSpacePerThread();
346  static char* RestoreThread(char* from);
347  static char* ArchiveThread(char* to);
348  static void FreeThreadResources();
349
350  // Garbage collection support.
351  static void Iterate(v8::internal::ObjectVisitor* v);
352  static char* Iterate(v8::internal::ObjectVisitor* v, char* data);
353
354
355  inline internal::Object** GetSpareOrNewBlock();
356  inline void DeleteExtensions(internal::Object** prev_limit);
357
358  inline void IncrementCallDepth() {call_depth_++;}
359  inline void DecrementCallDepth() {call_depth_--;}
360  inline bool CallDepthIsZero() { return call_depth_ == 0; }
361
362  inline void EnterContext(Handle<Object> context);
363  inline bool LeaveLastContext();
364
365  // Returns the last entered context or an empty handle if no
366  // contexts have been entered.
367  inline Handle<Object> LastEnteredContext();
368
369  inline void SaveContext(Context* context);
370  inline Context* RestoreContext();
371  inline bool HasSavedContexts();
372
373  inline List<internal::Object**>* blocks() { return &blocks_; }
374  inline bool ignore_out_of_memory() { return ignore_out_of_memory_; }
375  inline void set_ignore_out_of_memory(bool value) {
376    ignore_out_of_memory_ = value;
377  }
378
379 private:
380  void ResetAfterArchive() {
381    blocks_.Initialize(0);
382    entered_contexts_.Initialize(0);
383    saved_contexts_.Initialize(0);
384    spare_ = NULL;
385    ignore_out_of_memory_ = false;
386    call_depth_ = 0;
387  }
388
389  void Free() {
390    ASSERT(blocks_.length() == 0);
391    ASSERT(entered_contexts_.length() == 0);
392    ASSERT(saved_contexts_.length() == 0);
393    blocks_.Free();
394    entered_contexts_.Free();
395    saved_contexts_.Free();
396    if (spare_ != NULL) {
397      DeleteArray(spare_);
398      spare_ = NULL;
399    }
400    ASSERT(call_depth_ == 0);
401  }
402
403  List<internal::Object**> blocks_;
404  // Used as a stack to keep track of entered contexts.
405  List<Handle<Object> > entered_contexts_;
406  // Used as a stack to keep track of saved contexts.
407  List<Context*> saved_contexts_;
408  Object** spare_;
409  bool ignore_out_of_memory_;
410  int call_depth_;
411  // This is only used for threading support.
412  v8::ImplementationUtilities::HandleScopeData handle_scope_data_;
413
414  void IterateThis(ObjectVisitor* v);
415  char* RestoreThreadHelper(char* from);
416  char* ArchiveThreadHelper(char* to);
417
418  DISALLOW_COPY_AND_ASSIGN(HandleScopeImplementer);
419};
420
421
422static const int kHandleBlockSize = v8::internal::KB - 2;  // fit in one page
423
424
425void HandleScopeImplementer::SaveContext(Context* context) {
426  saved_contexts_.Add(context);
427}
428
429
430Context* HandleScopeImplementer::RestoreContext() {
431  return saved_contexts_.RemoveLast();
432}
433
434
435bool HandleScopeImplementer::HasSavedContexts() {
436  return !saved_contexts_.is_empty();
437}
438
439
440void HandleScopeImplementer::EnterContext(Handle<Object> context) {
441  entered_contexts_.Add(context);
442}
443
444
445bool HandleScopeImplementer::LeaveLastContext() {
446  if (entered_contexts_.is_empty()) return false;
447  entered_contexts_.RemoveLast();
448  return true;
449}
450
451
452Handle<Object> HandleScopeImplementer::LastEnteredContext() {
453  if (entered_contexts_.is_empty()) return Handle<Object>::null();
454  return entered_contexts_.last();
455}
456
457
458// If there's a spare block, use it for growing the current scope.
459internal::Object** HandleScopeImplementer::GetSpareOrNewBlock() {
460  internal::Object** block = (spare_ != NULL) ?
461      spare_ :
462      NewArray<internal::Object*>(kHandleBlockSize);
463  spare_ = NULL;
464  return block;
465}
466
467
468void HandleScopeImplementer::DeleteExtensions(internal::Object** prev_limit) {
469  while (!blocks_.is_empty()) {
470    internal::Object** block_start = blocks_.last();
471    internal::Object** block_limit = block_start + kHandleBlockSize;
472#ifdef DEBUG
473    // NoHandleAllocation may make the prev_limit to point inside the block.
474    if (block_start <= prev_limit && prev_limit <= block_limit) break;
475#else
476    if (prev_limit == block_limit) break;
477#endif
478
479    blocks_.RemoveLast();
480#ifdef DEBUG
481    v8::ImplementationUtilities::ZapHandleRange(block_start, block_limit);
482#endif
483    if (spare_ != NULL) {
484      DeleteArray(spare_);
485    }
486    spare_ = block_start;
487  }
488  ASSERT((blocks_.is_empty() && prev_limit == NULL) ||
489         (!blocks_.is_empty() && prev_limit != NULL));
490}
491
492} }  // namespace v8::internal
493
494#endif  // V8_API_H_
495