1 // Copyright 2011 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/v8.h"
6
7 #include "src/api.h"
8 #include "src/execution.h"
9 #include "src/heap/spaces-inl.h"
10 #include "src/messages.h"
11
12 namespace v8 {
13 namespace internal {
14
15
16 // If no message listeners have been registered this one is called
17 // by default.
DefaultMessageReport(Isolate * isolate,const MessageLocation * loc,Handle<Object> message_obj)18 void MessageHandler::DefaultMessageReport(Isolate* isolate,
19 const MessageLocation* loc,
20 Handle<Object> message_obj) {
21 SmartArrayPointer<char> str = GetLocalizedMessage(isolate, message_obj);
22 if (loc == NULL) {
23 PrintF("%s\n", str.get());
24 } else {
25 HandleScope scope(isolate);
26 Handle<Object> data(loc->script()->name(), isolate);
27 SmartArrayPointer<char> data_str;
28 if (data->IsString())
29 data_str = Handle<String>::cast(data)->ToCString(DISALLOW_NULLS);
30 PrintF("%s:%i: %s\n", data_str.get() ? data_str.get() : "<unknown>",
31 loc->start_pos(), str.get());
32 }
33 }
34
35
MakeMessageObject(Isolate * isolate,const char * type,MessageLocation * loc,Vector<Handle<Object>> args,Handle<JSArray> stack_frames)36 Handle<JSMessageObject> MessageHandler::MakeMessageObject(
37 Isolate* isolate,
38 const char* type,
39 MessageLocation* loc,
40 Vector< Handle<Object> > args,
41 Handle<JSArray> stack_frames) {
42 Factory* factory = isolate->factory();
43 Handle<String> type_handle = factory->InternalizeUtf8String(type);
44 Handle<FixedArray> arguments_elements =
45 factory->NewFixedArray(args.length());
46 for (int i = 0; i < args.length(); i++) {
47 arguments_elements->set(i, *args[i]);
48 }
49 Handle<JSArray> arguments_handle =
50 factory->NewJSArrayWithElements(arguments_elements);
51
52 int start = 0;
53 int end = 0;
54 Handle<Object> script_handle = factory->undefined_value();
55 if (loc) {
56 start = loc->start_pos();
57 end = loc->end_pos();
58 script_handle = Script::GetWrapper(loc->script());
59 }
60
61 Handle<Object> stack_frames_handle = stack_frames.is_null()
62 ? Handle<Object>::cast(factory->undefined_value())
63 : Handle<Object>::cast(stack_frames);
64
65 Handle<JSMessageObject> message =
66 factory->NewJSMessageObject(type_handle,
67 arguments_handle,
68 start,
69 end,
70 script_handle,
71 stack_frames_handle);
72
73 return message;
74 }
75
76
ReportMessage(Isolate * isolate,MessageLocation * loc,Handle<Object> message)77 void MessageHandler::ReportMessage(Isolate* isolate,
78 MessageLocation* loc,
79 Handle<Object> message) {
80 // We are calling into embedder's code which can throw exceptions.
81 // Thus we need to save current exception state, reset it to the clean one
82 // and ignore scheduled exceptions callbacks can throw.
83
84 // We pass the exception object into the message handler callback though.
85 Object* exception_object = isolate->heap()->undefined_value();
86 if (isolate->has_pending_exception()) {
87 exception_object = isolate->pending_exception();
88 }
89 Handle<Object> exception_handle(exception_object, isolate);
90
91 Isolate::ExceptionScope exception_scope(isolate);
92 isolate->clear_pending_exception();
93 isolate->set_external_caught_exception(false);
94
95 v8::Local<v8::Message> api_message_obj = v8::Utils::MessageToLocal(message);
96 v8::Local<v8::Value> api_exception_obj = v8::Utils::ToLocal(exception_handle);
97
98 v8::NeanderArray global_listeners(isolate->factory()->message_listeners());
99 int global_length = global_listeners.length();
100 if (global_length == 0) {
101 DefaultMessageReport(isolate, loc, message);
102 if (isolate->has_scheduled_exception()) {
103 isolate->clear_scheduled_exception();
104 }
105 } else {
106 for (int i = 0; i < global_length; i++) {
107 HandleScope scope(isolate);
108 if (global_listeners.get(i)->IsUndefined()) continue;
109 v8::NeanderObject listener(JSObject::cast(global_listeners.get(i)));
110 Handle<Foreign> callback_obj(Foreign::cast(listener.get(0)));
111 v8::MessageCallback callback =
112 FUNCTION_CAST<v8::MessageCallback>(callback_obj->foreign_address());
113 Handle<Object> callback_data(listener.get(1), isolate);
114 {
115 // Do not allow exceptions to propagate.
116 v8::TryCatch try_catch;
117 callback(api_message_obj, callback_data->IsUndefined()
118 ? api_exception_obj
119 : v8::Utils::ToLocal(callback_data));
120 }
121 if (isolate->has_scheduled_exception()) {
122 isolate->clear_scheduled_exception();
123 }
124 }
125 }
126 }
127
128
GetMessage(Isolate * isolate,Handle<Object> data)129 Handle<String> MessageHandler::GetMessage(Isolate* isolate,
130 Handle<Object> data) {
131 Factory* factory = isolate->factory();
132 Handle<String> fmt_str =
133 factory->InternalizeOneByteString(STATIC_CHAR_VECTOR("FormatMessage"));
134 Handle<JSFunction> fun = Handle<JSFunction>::cast(Object::GetProperty(
135 isolate->js_builtins_object(), fmt_str).ToHandleChecked());
136 Handle<JSMessageObject> message = Handle<JSMessageObject>::cast(data);
137 Handle<Object> argv[] = { Handle<Object>(message->type(), isolate),
138 Handle<Object>(message->arguments(), isolate) };
139
140 MaybeHandle<Object> maybe_result = Execution::TryCall(
141 fun, isolate->js_builtins_object(), arraysize(argv), argv);
142 Handle<Object> result;
143 if (!maybe_result.ToHandle(&result) || !result->IsString()) {
144 return factory->InternalizeOneByteString(STATIC_CHAR_VECTOR("<error>"));
145 }
146 Handle<String> result_string = Handle<String>::cast(result);
147 // A string that has been obtained from JS code in this way is
148 // likely to be a complicated ConsString of some sort. We flatten it
149 // here to improve the efficiency of converting it to a C string and
150 // other operations that are likely to take place (see GetLocalizedMessage
151 // for example).
152 result_string = String::Flatten(result_string);
153 return result_string;
154 }
155
156
GetLocalizedMessage(Isolate * isolate,Handle<Object> data)157 SmartArrayPointer<char> MessageHandler::GetLocalizedMessage(
158 Isolate* isolate,
159 Handle<Object> data) {
160 HandleScope scope(isolate);
161 return GetMessage(isolate, data)->ToCString(DISALLOW_NULLS);
162 }
163
164
165 } } // namespace v8::internal
166