src: add multi-context support

This commit makes it possible to use multiple V8 execution contexts
within a single event loop.  Put another way, handle and request wrap
objects now "remember" the context they belong to and switch back to
that context when the time comes to call into JS land.

This could have been done in a quick and hacky way by calling
v8::Object::GetCreationContext() on the wrap object right before
making a callback but that leaves a fairly wide margin for bugs.

Instead, we make the context explicit through a new Environment class
that encapsulates everything (or almost everything) that belongs to
the context.  Variables that used to be a static or a global are now
members of the aforementioned class.  An additional benefit is that
this approach should make it relatively straightforward to add full
isolate support in due course.

There is no JavaScript API yet but that will be added in the near
future.

This work was graciously sponsored by GitHub, Inc.

1 files changed, 7 insertions, 7 deletions

diff --git a/src/stream_wrap.h b/src/stream_wrap.h
index 6731fdbf75..26fb5d5ef6 100644
--- a/src/stream_wrap.h
+++ b/src/stream_wrap.h
@@ -22,11 +22,11 @@
 #ifndef SRC_STREAM_WRAP_H_
 #define SRC_STREAM_WRAP_H_
 
-#include "v8.h"
-#include "node.h"
+#include "env.h"
 #include "handle_wrap.h"
 #include "req_wrap.h"
 #include "string_bytes.h"
+#include "v8.h"
 
 namespace node {
 
@@ -37,8 +37,8 @@ typedef class ReqWrap<uv_shutdown_t> ShutdownWrap;
 
 class WriteWrap: public ReqWrap<uv_write_t> {
  public:
-  WriteWrap(v8::Local<v8::Object> obj, StreamWrap* wrap)
-      : ReqWrap<uv_write_t>(obj)
+  WriteWrap(Environment* env, v8::Local<v8::Object> obj, StreamWrap* wrap)
+      : ReqWrap<uv_write_t>(env, obj)
       , wrap_(wrap) {
   }
 
@@ -108,8 +108,6 @@ class StreamWrap : public HandleWrap {
       delete old;
   }
 
-  static void Initialize(v8::Handle<v8::Object> target);
-
   static void GetFD(v8::Local<v8::String>,
                     const v8::PropertyCallbackInfo<v8::Value>&);
 
@@ -148,7 +146,9 @@ class StreamWrap : public HandleWrap {
  protected:
   static size_t WriteBuffer(v8::Handle<v8::Value> val, uv_buf_t* buf);
 
-  StreamWrap(v8::Handle<v8::Object> object, uv_stream_t* stream);
+  StreamWrap(Environment* env,
+             v8::Local<v8::Object> object,
+             uv_stream_t* stream);
 
   ~StreamWrap() {
     if (callbacks_ != &default_callbacks_) {