xpcom/proxy/src/nsProxyEventObject.cpp
author Chris Double <chris.double@double.co.nz>
Fri, 31 Oct 2008 10:45:04 +1300
changeset 21124 2a5a08ab330498246befc0288b8e894ab2f2d38d
parent 14520 8e9e117e9c054a3583e36cc771ac4f0eb236f7b8
child 46403 db6f8068e9a5d74f6a8756cb48ef0f2a8e3eb5b8
permissions -rw-r--r--
Bug 462409 - Update liboggplay to get fixes for Solaris and EOF issues - rs=roc

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
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 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
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 *
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 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Pierre Phaneuf <pp@ludusdesign.com>
 *   Benjamin Smedberg <benjamin@smedbergs.us>
 *
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#include "prprf.h"
#include "prmem.h"

#include "nscore.h"
#include "nsProxyEventPrivate.h"
#include "nsIThreadInternal.h"

#include "nsServiceManagerUtils.h"

#include "nsHashtable.h"

#include "nsIInterfaceInfoManager.h"
#include "xptcall.h"

#include "nsAutoLock.h"

nsProxyEventObject::nsProxyEventObject(nsProxyObject *aParent,
                            nsProxyEventClass* aClass,
                            already_AddRefed<nsISomeInterface> aRealInterface,
                            nsresult *rv)
    : mClass(aClass),
      mProxyObject(aParent),
      mRealInterface(aRealInterface),
      mNext(nsnull)
{
    *rv = InitStub(aClass->GetProxiedIID());
}

nsProxyEventObject::~nsProxyEventObject()
{
    // This destructor must *not* be called within the POM lock
    // XXX assert this!

    // mRealInterface must be released before mProxyObject so that the last
    // release of the proxied object is proxied to the correct thread.
    // See bug 337492.
    mRealInterface = nsnull;
}

//
// nsISupports implementation...
//

NS_IMETHODIMP_(nsrefcnt)
nsProxyEventObject::AddRef()
{
    nsAutoLock lock(nsProxyObjectManager::GetInstance()->GetLock());
    return LockedAddRef();
}

nsrefcnt
nsProxyEventObject::LockedAddRef()
{
    ++mRefCnt;
    NS_LOG_ADDREF(this, mRefCnt, "nsProxyEventObject", sizeof(nsProxyEventObject));
    return mRefCnt;
}

NS_IMETHODIMP_(nsrefcnt)
nsProxyEventObject::Release(void)
{
    {
        nsAutoLock lock(nsProxyObjectManager::GetInstance()->GetLock());
        NS_PRECONDITION(0 != mRefCnt, "dup release");

        --mRefCnt;
        NS_LOG_RELEASE(this, mRefCnt, "nsProxyEventObject");

        if (mRefCnt)
            return mRefCnt;

        mProxyObject->LockedRemove(this);
    }

    // call the destructor outside of the lock so that we aren't holding the
    // lock when we release the object
    NS_DELETEXPCOM(this);
    return 0;
}

NS_IMETHODIMP
nsProxyEventObject::QueryInterface(REFNSIID aIID, void** aInstancePtr)
{
    if( aIID.Equals(GetClass()->GetProxiedIID()) )
    {
        *aInstancePtr = static_cast<nsISupports*>(mXPTCStub);
        NS_ADDREF_THIS();
        return NS_OK;
    }
        
    return mProxyObject->QueryInterface(aIID, aInstancePtr);
}

//
// nsXPTCStubBase implementation...
//

nsresult
nsProxyEventObject::convertMiniVariantToVariant(const XPTMethodDescriptor *methodInfo, 
                                                nsXPTCMiniVariant * params, 
                                                nsXPTCVariant **fullParam, 
                                                uint8 *outParamCount)
{
    uint8 paramCount = methodInfo->num_args;
    *outParamCount = paramCount;
    *fullParam = nsnull;

    if (!paramCount) return NS_OK;
        
    *fullParam = (nsXPTCVariant*)malloc(sizeof(nsXPTCVariant) * paramCount);
    
    if (*fullParam == nsnull)
        return NS_ERROR_OUT_OF_MEMORY;
    
    for (int i = 0; i < paramCount; i++)
    {
        const nsXPTParamInfo& paramInfo = methodInfo->params[i];
        if ((GetProxyType() & NS_PROXY_ASYNC) &&
            (paramInfo.IsOut() || paramInfo.IsDipper()))
        {
            NS_WARNING("Async proxying of out parameters is not supported"); 
            free(*fullParam);
            return NS_ERROR_PROXY_INVALID_OUT_PARAMETER;
        }
        uint8 flags = paramInfo.IsOut() ? nsXPTCVariant::PTR_IS_DATA : 0;
        (*fullParam)[i].Init(params[i], paramInfo.GetType(), flags);
    }
    
    return NS_OK;
}

class nsProxyThreadFilter : public nsIThreadEventFilter
{
public:
    NS_DECL_ISUPPORTS
    NS_DECL_NSITHREADEVENTFILTER
};

NS_IMPL_THREADSAFE_ISUPPORTS1(nsProxyThreadFilter, nsIThreadEventFilter)

NS_DEFINE_IID(kFilterIID, NS_PROXYEVENT_FILTER_IID);

NS_IMETHODIMP_(PRBool)
nsProxyThreadFilter::AcceptEvent(nsIRunnable *event)
{
    PROXY_LOG(("PROXY(%p): filter event [%p]\n", this, event));

    // If we encounter one of our proxy events that is for a synchronous method
    // call, then we want to put it in our event queue for processing.  Else,
    // we want to allow the event to be dispatched to the thread's event queue
    // for processing later once we complete the current sync method call.
    
    nsRefPtr<nsProxyObjectCallInfo> poci;
    event->QueryInterface(kFilterIID, getter_AddRefs(poci));
    return poci && poci->IsSync();
}

NS_IMETHODIMP
nsProxyEventObject::CallMethod(PRUint16 methodIndex,
                               const XPTMethodDescriptor* methodInfo,
                               nsXPTCMiniVariant * params)
{
    NS_ASSERTION(methodIndex > 2,
                 "Calling QI/AddRef/Release through CallMethod");
    nsresult rv;

    if (XPT_MD_IS_NOTXPCOM(methodInfo->flags))
        return NS_ERROR_PROXY_INVALID_IN_PARAMETER;

    nsXPTCVariant *fullParam;
    uint8 paramCount;
    rv = convertMiniVariantToVariant(methodInfo, params,
                                     &fullParam, &paramCount);
    if (NS_FAILED(rv))
        return rv;

    PRBool callDirectly = PR_FALSE;
    if (GetProxyType() & NS_PROXY_SYNC &&
        NS_SUCCEEDED(GetTarget()->IsOnCurrentThread(&callDirectly)) &&
        callDirectly) {

        // invoke directly using xptc
        rv = NS_InvokeByIndex(mRealInterface, methodIndex,
                              paramCount, fullParam);

        if (fullParam)
            free(fullParam);

        return rv;
    }

    nsRefPtr<nsProxyObjectCallInfo> proxyInfo =
        new nsProxyObjectCallInfo(this, methodInfo, methodIndex,
                                  fullParam, paramCount);
    if (!proxyInfo)
        return NS_ERROR_OUT_OF_MEMORY;

    if (! (GetProxyType() & NS_PROXY_SYNC)) {
        return GetTarget()->Dispatch(proxyInfo, NS_DISPATCH_NORMAL);
    }

    // Post synchronously

    nsIThread *thread = NS_GetCurrentThread();
    nsCOMPtr<nsIThreadInternal> threadInt = do_QueryInterface(thread);
    NS_ENSURE_STATE(threadInt);

    // Install  thread filter to limit event processing only to 
    // nsProxyObjectCallInfo instances.  XXX Add support for sequencing?
    nsRefPtr<nsProxyThreadFilter> filter = new nsProxyThreadFilter();
    if (!filter)
        return NS_ERROR_OUT_OF_MEMORY;
    threadInt->PushEventQueue(filter);

    proxyInfo->SetCallersTarget(thread);
    
    // Dispatch can fail if the thread is shutting down
    rv = GetTarget()->Dispatch(proxyInfo, NS_DISPATCH_NORMAL);
    if (NS_SUCCEEDED(rv)) {
        while (!proxyInfo->GetCompleted()) {
            if (!NS_ProcessNextEvent(thread)) {
                rv = NS_ERROR_UNEXPECTED;
                break;
            }
        }
        rv = proxyInfo->GetResult();
    } else {
        NS_WARNING("Failed to dispatch nsProxyCallEvent");
    }

    threadInt->PopEventQueue();

    PROXY_LOG(("PROXY(%p): PostAndWait exit [%p %x]\n", this, proxyInfo.get(), rv));
    return rv;
}