Introduce a v8::Platform class that bundles embedder callbacks

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 736f0b00d7ac833ca3409ebd703a90f8ef49a5bc..29fc635541d76214837b51889ce929bd03360ee0 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -40,6 +40,9 @@
 #include "counters.h"
 #include "cpu-profiler.h"
 #include "debug.h"
+#ifdef V8_USE_DEFAULT_PLATFORM
+#include "default-platform.h"
+#endif
 #include "deoptimizer.h"
 #include "execution.h"
 #include "global-handles.h"
@@ -5042,11 +5045,47 @@ static void* ExternalValue(i::Object* obj) {
 // --- E n v i r o n m e n t ---
 
 
+namespace {
+
+Platform* g_platform = NULL;
+
+}  // namespace
+
+
+void Platform::Initialize(Platform* platform) {
+#ifdef V8_USE_DEFAULT_PLATFORM
+  FATAL("Can't override v8::Platform when using default implementation");
+#else
+  ASSERT(!g_platform);
+  g_platform = platform;
+#endif
+}
+
+
+void Platform::Shutdown() {
+#ifdef V8_USE_DEFAULT_PLATFORM
+  FATAL("Can't override v8::Platform when using default implementation");
+#else
+  ASSERT(g_platform);
+  g_platform = NULL;
+#endif
+}
+
+
+Platform* Platform::GetCurrent() {
+  ASSERT(g_platform);
+  return g_platform;
+}
+
+
 bool v8::V8::Initialize() {
   i::Isolate* isolate = i::Isolate::UncheckedCurrent();
   if (isolate != NULL && isolate->IsInitialized()) {
     return true;
   }
+#ifdef V8_USE_DEFAULT_PLATFORM
+  g_platform = new i::DefaultPlatform;

[Benedikt Meurer, 2013/11/18 15:34:44]

I think platform initialization should be first in V8::Initialize(). If we
really want to be able to move all the platform stuff to the Platform class at
some point, then we will need an initialized Platform to use even basic stuff
such as TLS. So, please do:

if (!g_platform) g_platform = new i::DefaultPlatform;

at the beginning.

[jochen (gone - plz use gerrit), 2013/11/18 16:27:56]

Done (except for the default magic)

+#endif
   return InitializeHelper(isolate);
 }
 
@@ -5111,6 +5150,11 @@ bool v8::V8::Dispose() {
     return false;
   }
   i::V8::TearDown();
+#ifdef V8_USE_DEFAULT_PLATFORM
+  i::DefaultPlatform* platform = static_cast<i::DefaultPlatform*>(g_platform);
+  g_platform = NULL;
+  delete platform;
+#endif
   return true;
 }