/*
 * Copyright (C) 2008 Collin Jackson  <collinj@webkit.org>
 * Copyright (C) 2009 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 AND ITS CONTRIBUTORS "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 "DNS.h"

#include "PlatformString.h"
#include <wtf/RetainPtr.h>

#if PLATFORM(WIN)
#include "ResourceHandle.h" // for loaderRunLoop()
#endif

#ifdef BUILDING_ON_TIGER
// This function is available on Tiger, but not declared in the CFRunLoop.h header on Tiger.
extern "C" CFRunLoopRef CFRunLoopGetMain();
#endif

namespace WebCore {

static void clientCallback(CFHostRef theHost, CFHostInfoType, const CFStreamError*, void*)
{
    CFRelease(theHost);
}

void prefetchDNS(const String& hostname)
{
    RetainPtr<CFStringRef> hostnameCF(AdoptCF, hostname.createCFString());
    RetainPtr<CFHostRef> host(AdoptCF, CFHostCreateWithName(0, hostnameCF.get()));
    if (!host)
        return;
    CFHostClientContext context = { 0, 0, 0, 0, 0 };
    Boolean result = CFHostSetClient(host.get(), clientCallback, &context);
    ASSERT_UNUSED(result, result);
#if !PLATFORM(WIN)
    CFHostScheduleWithRunLoop(host.get(), CFRunLoopGetMain(), kCFRunLoopCommonModes);
#else
    // On Windows, we run a separate thread with CFRunLoop, which is where clientCallback will be called.
    CFHostScheduleWithRunLoop(host.get(), ResourceHandle::loaderRunLoop(), kCFRunLoopDefaultMode);
#endif
    CFHostStartInfoResolution(host.get(), kCFHostAddresses, 0);
    host.releaseRef(); // The host will be released from clientCallback().
}

}