JavaScriptCore/API/JSContextRef.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/JavaScriptCore/API/JSContextRef.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "JSContextRef.h"
+#include "JSContextRefPrivate.h"
+
+#include "APICast.h"
+#include "InitializeThreading.h"
+#include "JSCallbackObject.h"
+#include "JSClassRef.h"
+#include "JSGlobalObject.h"
+#include "JSObject.h"
+#include <wtf/text/StringHash.h>
+
+#if OS(DARWIN)
+#include <mach-o/dyld.h>
+
+static const int32_t webkitFirstVersionWithConcurrentGlobalContexts = 0x2100500; // 528.5.0
+#endif
+
+using namespace JSC;
+
+JSContextGroupRef JSContextGroupCreate()
+{
+    initializeThreading();
+    return toRef(JSGlobalData::createContextGroup(ThreadStackTypeSmall).releaseRef());
+}
+
+JSContextGroupRef JSContextGroupRetain(JSContextGroupRef group)
+{
+    toJS(group)->ref();
+    return group;
+}
+
+void JSContextGroupRelease(JSContextGroupRef group)
+{
+    toJS(group)->deref();
+}
+
+JSGlobalContextRef JSGlobalContextCreate(JSClassRef globalObjectClass)
+{
+    initializeThreading();
+#if OS(DARWIN)
+    // When running on Tiger or Leopard, or if the application was linked before JSGlobalContextCreate was changed
+    // to use a unique JSGlobalData, we use a shared one for compatibility.
+#if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD)
+    if (NSVersionOfLinkTimeLibrary("JavaScriptCore") <= webkitFirstVersionWithConcurrentGlobalContexts) {
+#else
+    {
+#endif
+        JSLock lock(LockForReal);
+        return JSGlobalContextCreateInGroup(toRef(&JSGlobalData::sharedInstance()), globalObjectClass);
+    }
+#endif // OS(DARWIN)
+
+    return JSGlobalContextCreateInGroup(0, globalObjectClass);
+}
+
+JSGlobalContextRef JSGlobalContextCreateInGroup(JSContextGroupRef group, JSClassRef globalObjectClass)
+{
+    initializeThreading();
+
+    JSLock lock(LockForReal);
+    RefPtr<JSGlobalData> globalData = group ? PassRefPtr<JSGlobalData>(toJS(group)) : JSGlobalData::createContextGroup(ThreadStackTypeSmall);
+
+    APIEntryShim entryShim(globalData.get(), false);
+
+#if ENABLE(JSC_MULTIPLE_THREADS)
+    globalData->makeUsableFromMultipleThreads();
+#endif
+
+    if (!globalObjectClass) {
+        JSGlobalObject* globalObject = new (globalData.get()) JSGlobalObject;
+        return JSGlobalContextRetain(toGlobalRef(globalObject->globalExec()));
+    }
+
+    JSGlobalObject* globalObject = new (globalData.get()) JSCallbackObject<JSGlobalObject>(globalObjectClass, JSCallbackObject<JSGlobalObject>::createStructure(jsNull()));
+    ExecState* exec = globalObject->globalExec();
+    JSValue prototype = globalObjectClass->prototype(exec);
+    if (!prototype)
+        prototype = jsNull();
+    globalObject->resetPrototype(prototype);
+    return JSGlobalContextRetain(toGlobalRef(exec));
+}
+
+JSGlobalContextRef JSGlobalContextRetain(JSGlobalContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    APIEntryShim entryShim(exec);
+
+    JSGlobalData& globalData = exec->globalData();
+    gcProtect(exec->dynamicGlobalObject());
+    globalData.ref();
+    return ctx;
+}
+
+void JSGlobalContextRelease(JSGlobalContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    JSLock lock(exec);
+
+    JSGlobalData& globalData = exec->globalData();
+    JSGlobalObject* dgo = exec->dynamicGlobalObject();
+    IdentifierTable* savedIdentifierTable = wtfThreadData().setCurrentIdentifierTable(globalData.identifierTable);
+
+    // One reference is held by JSGlobalObject, another added by JSGlobalContextRetain().
+    bool releasingContextGroup = globalData.refCount() == 2;
+    bool releasingGlobalObject = Heap::heap(dgo)->unprotect(dgo);
+    // If this is the last reference to a global data, it should also
+    // be the only remaining reference to the global object too!
+    ASSERT(!releasingContextGroup || releasingGlobalObject);
+
+    // An API 'JSGlobalContextRef' retains two things - a global object and a
+    // global data (or context group, in API terminology).
+    // * If this is the last reference to any contexts in the given context group,
+    //   call destroy on the heap (the global data is being  freed).
+    // * If this was the last reference to the global object, then unprotecting
+    //   it may  release a lot of GC memory - run the garbage collector now.
+    // * If there are more references remaining the the global object, then do nothing
+    //   (specifically that is more protects, which we assume come from other JSGlobalContextRefs).
+    if (releasingContextGroup)
+        globalData.heap.destroy();
+    else if (releasingGlobalObject)
+        globalData.heap.collectAllGarbage();
+
+    globalData.deref();
+
+    wtfThreadData().setCurrentIdentifierTable(savedIdentifierTable);
+}
+
+JSObjectRef JSContextGetGlobalObject(JSContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    APIEntryShim entryShim(exec);
+
+    // It is necessary to call toThisObject to get the wrapper object when used with WebCore.
+    return toRef(exec->lexicalGlobalObject()->toThisObject(exec));
+}
+
+JSContextGroupRef JSContextGetGroup(JSContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    return toRef(&exec->globalData());
+}
+
+JSGlobalContextRef JSContextGetGlobalContext(JSContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    APIEntryShim entryShim(exec);
+
+    return toGlobalRef(exec->lexicalGlobalObject()->globalExec());
+}