1 #ifndef SRC_JS_NATIVE_API_V8_H_
2 #define SRC_JS_NATIVE_API_V8_H_
3
4 // This file needs to be compatible with C compilers.
5 #include <string.h> // NOLINT(modernize-deprecated-headers)
6 #include "js_native_api_types.h"
7 #include "js_native_api_v8_internals.h"
8
9 static napi_status napi_clear_last_error(napi_env env);
10
11 namespace v8impl {
12
13 class RefTracker {
14 public:
RefTracker()15 RefTracker() {}
~RefTracker()16 virtual ~RefTracker() {}
Finalize(bool isEnvTeardown)17 virtual void Finalize(bool isEnvTeardown) {}
18
19 typedef RefTracker RefList;
20
Link(RefList * list)21 inline void Link(RefList* list) {
22 prev_ = list;
23 next_ = list->next_;
24 if (next_ != nullptr) {
25 next_->prev_ = this;
26 }
27 list->next_ = this;
28 }
29
Unlink()30 inline void Unlink() {
31 if (prev_ != nullptr) {
32 prev_->next_ = next_;
33 }
34 if (next_ != nullptr) {
35 next_->prev_ = prev_;
36 }
37 prev_ = nullptr;
38 next_ = nullptr;
39 }
40
FinalizeAll(RefList * list)41 static void FinalizeAll(RefList* list) {
42 while (list->next_ != nullptr) {
43 list->next_->Finalize(true);
44 }
45 }
46
47 private:
48 RefList* next_ = nullptr;
49 RefList* prev_ = nullptr;
50 };
51
52 } // end of namespace v8impl
53
54 struct napi_env__ {
napi_env__napi_env__55 explicit napi_env__(v8::Local<v8::Context> context)
56 : isolate(context->GetIsolate()),
57 context_persistent(isolate, context) {
58 CHECK_EQ(isolate, context->GetIsolate());
59 }
~napi_env__napi_env__60 virtual ~napi_env__() {
61 // First we must finalize those references that have `napi_finalizer`
62 // callbacks. The reason is that addons might store other references which
63 // they delete during their `napi_finalizer` callbacks. If we deleted such
64 // references here first, they would be doubly deleted when the
65 // `napi_finalizer` deleted them subsequently.
66 v8impl::RefTracker::FinalizeAll(&finalizing_reflist);
67 v8impl::RefTracker::FinalizeAll(&reflist);
68 }
69 v8::Isolate* const isolate; // Shortcut for context()->GetIsolate()
70 v8impl::Persistent<v8::Context> context_persistent;
71
contextnapi_env__72 inline v8::Local<v8::Context> context() const {
73 return v8impl::PersistentToLocal::Strong(context_persistent);
74 }
75
Refnapi_env__76 inline void Ref() { refs++; }
Unrefnapi_env__77 inline void Unref() { if ( --refs == 0) delete this; }
78
can_call_into_jsnapi_env__79 virtual bool can_call_into_js() const { return true; }
mark_arraybuffer_as_untransferablenapi_env__80 virtual v8::Maybe<bool> mark_arraybuffer_as_untransferable(
81 v8::Local<v8::ArrayBuffer> ab) const {
82 return v8::Just(true);
83 }
84
85 static inline void
HandleThrownapi_env__86 HandleThrow(napi_env env, v8::Local<v8::Value> value) {
87 env->isolate->ThrowException(value);
88 }
89
90 template <typename T, typename U = decltype(HandleThrow)>
91 inline void CallIntoModule(T&& call, U&& handle_exception = HandleThrow) {
92 int open_handle_scopes_before = open_handle_scopes;
93 int open_callback_scopes_before = open_callback_scopes;
94 napi_clear_last_error(this);
95 call(this);
96 CHECK_EQ(open_handle_scopes, open_handle_scopes_before);
97 CHECK_EQ(open_callback_scopes, open_callback_scopes_before);
98 if (!last_exception.IsEmpty()) {
99 handle_exception(this, last_exception.Get(this->isolate));
100 last_exception.Reset();
101 }
102 }
103
CallFinalizernapi_env__104 virtual void CallFinalizer(napi_finalize cb, void* data, void* hint) {
105 v8::HandleScope handle_scope(isolate);
106 CallIntoModule([&](napi_env env) {
107 cb(env, data, hint);
108 });
109 }
110
111 v8impl::Persistent<v8::Value> last_exception;
112
113 // We store references in two different lists, depending on whether they have
114 // `napi_finalizer` callbacks, because we must first finalize the ones that
115 // have such a callback. See `~napi_env__()` above for details.
116 v8impl::RefTracker::RefList reflist;
117 v8impl::RefTracker::RefList finalizing_reflist;
118 napi_extended_error_info last_error;
119 int open_handle_scopes = 0;
120 int open_callback_scopes = 0;
121 int refs = 1;
122 void* instance_data = nullptr;
123 };
124
napi_clear_last_error(napi_env env)125 static inline napi_status napi_clear_last_error(napi_env env) {
126 env->last_error.error_code = napi_ok;
127
128 // TODO(boingoing): Should this be a callback?
129 env->last_error.engine_error_code = 0;
130 env->last_error.engine_reserved = nullptr;
131 return napi_ok;
132 }
133
134 static inline
135 napi_status napi_set_last_error(napi_env env, napi_status error_code,
136 uint32_t engine_error_code = 0,
137 void* engine_reserved = nullptr) {
138 env->last_error.error_code = error_code;
139 env->last_error.engine_error_code = engine_error_code;
140 env->last_error.engine_reserved = engine_reserved;
141 return error_code;
142 }
143
144 #define RETURN_STATUS_IF_FALSE(env, condition, status) \
145 do { \
146 if (!(condition)) { \
147 return napi_set_last_error((env), (status)); \
148 } \
149 } while (0)
150
151 #define RETURN_STATUS_IF_FALSE_WITH_PREAMBLE(env, condition, status) \
152 do { \
153 if (!(condition)) { \
154 return napi_set_last_error( \
155 (env), try_catch.HasCaught() ? napi_pending_exception : (status)); \
156 } \
157 } while (0)
158
159 #define CHECK_ENV(env) \
160 do { \
161 if ((env) == nullptr) { \
162 return napi_invalid_arg; \
163 } \
164 } while (0)
165
166 #define CHECK_ARG(env, arg) \
167 RETURN_STATUS_IF_FALSE((env), ((arg) != nullptr), napi_invalid_arg)
168
169 #define CHECK_ARG_WITH_PREAMBLE(env, arg) \
170 RETURN_STATUS_IF_FALSE_WITH_PREAMBLE((env), \
171 ((arg) != nullptr), \
172 napi_invalid_arg)
173
174 #define CHECK_MAYBE_EMPTY(env, maybe, status) \
175 RETURN_STATUS_IF_FALSE((env), !((maybe).IsEmpty()), (status))
176
177 #define CHECK_MAYBE_EMPTY_WITH_PREAMBLE(env, maybe, status) \
178 RETURN_STATUS_IF_FALSE_WITH_PREAMBLE((env), !((maybe).IsEmpty()), (status))
179
180 // NAPI_PREAMBLE is not wrapped in do..while: try_catch must have function scope
181 #define NAPI_PREAMBLE(env) \
182 CHECK_ENV((env)); \
183 RETURN_STATUS_IF_FALSE((env), \
184 (env)->last_exception.IsEmpty() && (env)->can_call_into_js(), \
185 napi_pending_exception); \
186 napi_clear_last_error((env)); \
187 v8impl::TryCatch try_catch((env))
188
189 #define CHECK_TO_TYPE(env, type, context, result, src, status) \
190 do { \
191 CHECK_ARG((env), (src)); \
192 auto maybe = v8impl::V8LocalValueFromJsValue((src))->To##type((context)); \
193 CHECK_MAYBE_EMPTY((env), maybe, (status)); \
194 (result) = maybe.ToLocalChecked(); \
195 } while (0)
196
197 #define CHECK_TO_TYPE_WITH_PREAMBLE(env, type, context, result, src, status) \
198 do { \
199 CHECK_ARG_WITH_PREAMBLE((env), (src)); \
200 auto maybe = v8impl::V8LocalValueFromJsValue((src))->To##type((context)); \
201 CHECK_MAYBE_EMPTY_WITH_PREAMBLE((env), maybe, (status)); \
202 (result) = maybe.ToLocalChecked(); \
203 } while (0)
204
205 #define CHECK_TO_FUNCTION(env, result, src) \
206 do { \
207 CHECK_ARG((env), (src)); \
208 v8::Local<v8::Value> v8value = v8impl::V8LocalValueFromJsValue((src)); \
209 RETURN_STATUS_IF_FALSE((env), v8value->IsFunction(), napi_invalid_arg); \
210 (result) = v8value.As<v8::Function>(); \
211 } while (0)
212
213 #define CHECK_TO_OBJECT(env, context, result, src) \
214 CHECK_TO_TYPE((env), Object, (context), (result), (src), napi_object_expected)
215
216 #define CHECK_TO_OBJECT_WITH_PREAMBLE(env, context, result, src) \
217 CHECK_TO_TYPE_WITH_PREAMBLE((env), \
218 Object, \
219 (context), \
220 (result), \
221 (src), \
222 napi_object_expected)
223
224 #define CHECK_TO_STRING(env, context, result, src) \
225 CHECK_TO_TYPE((env), String, (context), (result), (src), napi_string_expected)
226
227 #define GET_RETURN_STATUS(env) \
228 (!try_catch.HasCaught() ? napi_ok \
229 : napi_set_last_error((env), napi_pending_exception))
230
231 #define THROW_RANGE_ERROR_IF_FALSE(env, condition, error, message) \
232 do { \
233 if (!(condition)) { \
234 napi_throw_range_error((env), (error), (message)); \
235 return napi_set_last_error((env), napi_generic_failure); \
236 } \
237 } while (0)
238
239 #define RETURN_STATUS_IF_FALSE_WITH_PREAMBLE(env, condition, status) \
240 do { \
241 if (!(condition)) { \
242 return napi_set_last_error( \
243 (env), try_catch.HasCaught() ? napi_pending_exception : (status)); \
244 } \
245 } while (0)
246
247 #define CHECK_MAYBE_EMPTY_WITH_PREAMBLE(env, maybe, status) \
248 RETURN_STATUS_IF_FALSE_WITH_PREAMBLE((env), !((maybe).IsEmpty()), (status))
249
250 namespace v8impl {
251
252 //=== Conversion between V8 Handles and napi_value ========================
253
254 // This asserts v8::Local<> will always be implemented with a single
255 // pointer field so that we can pass it around as a void*.
256 static_assert(sizeof(v8::Local<v8::Value>) == sizeof(napi_value),
257 "Cannot convert between v8::Local<v8::Value> and napi_value");
258
JsValueFromV8LocalValue(v8::Local<v8::Value> local)259 inline napi_value JsValueFromV8LocalValue(v8::Local<v8::Value> local) {
260 return reinterpret_cast<napi_value>(*local);
261 }
262
V8LocalValueFromJsValue(napi_value v)263 inline v8::Local<v8::Value> V8LocalValueFromJsValue(napi_value v) {
264 v8::Local<v8::Value> local;
265 memcpy(static_cast<void*>(&local), &v, sizeof(v));
266 return local;
267 }
268
269 // Adapter for napi_finalize callbacks.
270 class Finalizer {
271 public:
272 // Some Finalizers are run during shutdown when the napi_env is destroyed,
273 // and some need to keep an explicit reference to the napi_env because they
274 // are run independently.
275 enum EnvReferenceMode {
276 kNoEnvReference,
277 kKeepEnvReference
278 };
279
280 protected:
281 Finalizer(napi_env env,
282 napi_finalize finalize_callback,
283 void* finalize_data,
284 void* finalize_hint,
285 EnvReferenceMode refmode = kNoEnvReference)
_env(env)286 : _env(env),
287 _finalize_callback(finalize_callback),
288 _finalize_data(finalize_data),
289 _finalize_hint(finalize_hint),
290 _has_env_reference(refmode == kKeepEnvReference) {
291 if (_has_env_reference)
292 _env->Ref();
293 }
294
~Finalizer()295 ~Finalizer() {
296 if (_has_env_reference)
297 _env->Unref();
298 }
299
300 public:
301 static Finalizer* New(napi_env env,
302 napi_finalize finalize_callback = nullptr,
303 void* finalize_data = nullptr,
304 void* finalize_hint = nullptr,
305 EnvReferenceMode refmode = kNoEnvReference) {
306 return new Finalizer(
307 env, finalize_callback, finalize_data, finalize_hint, refmode);
308 }
309
Delete(Finalizer * finalizer)310 static void Delete(Finalizer* finalizer) {
311 delete finalizer;
312 }
313
314 protected:
315 napi_env _env;
316 napi_finalize _finalize_callback;
317 void* _finalize_data;
318 void* _finalize_hint;
319 bool _finalize_ran = false;
320 bool _has_env_reference = false;
321 };
322
323 class TryCatch : public v8::TryCatch {
324 public:
TryCatch(napi_env env)325 explicit TryCatch(napi_env env)
326 : v8::TryCatch(env->isolate), _env(env) {}
327
~TryCatch()328 ~TryCatch() {
329 if (HasCaught()) {
330 _env->last_exception.Reset(_env->isolate, Exception());
331 }
332 }
333
334 private:
335 napi_env _env;
336 };
337
338 } // end of namespace v8impl
339
340 #endif // SRC_JS_NATIVE_API_V8_H_
341