/*

 * Copyright (C) 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. 

 */

#import "config.h"

#import "ThreadCheck.h"

#import "StringHash.h"

#import <wtf/HashSet.h>

#import <wtf/StdLibExtras.h>

namespace WebCore {

static bool didReadThreadViolationBehaviorFromUserDefaults = false;

static bool threadViolationBehaviorIsDefault = true;

static ThreadViolationBehavior threadViolationBehavior[MaximumThreadViolationRound] = { RaiseExceptionOnThreadViolation, RaiseExceptionOnThreadViolation };

static void readThreadViolationBehaviorFromUserDefaults()

{

    didReadThreadViolationBehaviorFromUserDefaults = true;

    ThreadViolationBehavior newBehavior = LogOnFirstThreadViolation;

    NSString *threadCheckLevel = [[NSUserDefaults standardUserDefaults] stringForKey:@"WebCoreThreadCheck"];

    if (!threadCheckLevel)

        return;

    if ([threadCheckLevel isEqualToString:@"None"])

        newBehavior = NoThreadCheck;

    else if ([threadCheckLevel isEqualToString:@"Exception"])

        newBehavior = RaiseExceptionOnThreadViolation;

    else if ([threadCheckLevel isEqualToString:@"Log"])

        newBehavior = LogOnThreadViolation;

    else if ([threadCheckLevel isEqualToString:@"LogOnce"])

        newBehavior = LogOnFirstThreadViolation;

    else

        ASSERT_NOT_REACHED();

    threadViolationBehaviorIsDefault = false;

    for (unsigned i = 0; i < MaximumThreadViolationRound; ++i)

        threadViolationBehavior[i] = newBehavior;

}

void setDefaultThreadViolationBehavior(ThreadViolationBehavior behavior, ThreadViolationRound round)

{

    ASSERT(round < MaximumThreadViolationRound);

    if (round >= MaximumThreadViolationRound)

        return;

    if (!didReadThreadViolationBehaviorFromUserDefaults)

        readThreadViolationBehaviorFromUserDefaults();

    if (threadViolationBehaviorIsDefault)

        threadViolationBehavior[round] = behavior;

}

void reportThreadViolation(const char* function, ThreadViolationRound round)

{

    ASSERT(round < MaximumThreadViolationRound);

    if (round >= MaximumThreadViolationRound)

        return;

    if (!didReadThreadViolationBehaviorFromUserDefaults)

        readThreadViolationBehaviorFromUserDefaults();

    if (threadViolationBehavior[round] == NoThreadCheck)

        return;

    if (pthread_main_np())

        return;

    WebCoreReportThreadViolation(function, round);

}

} // namespace WebCore

// Split out the actual reporting of the thread violation to make it easier to set a breakpoint

void WebCoreReportThreadViolation(const char* function, WebCore::ThreadViolationRound round)

{

    using namespace WebCore;

    ASSERT(round < MaximumThreadViolationRound);

    if (round >= MaximumThreadViolationRound)

        return;

    DEFINE_STATIC_LOCAL(HashSet<String>, loggedFunctions, ());

    switch (threadViolationBehavior[round]) {

        case NoThreadCheck:

            break;

        case LogOnFirstThreadViolation:

            if (loggedFunctions.add(function).second) {

                NSLog(@"WebKit Threading Violation - %s called from secondary thread", function);

                NSLog(@"Additional threading violations for this function will not be logged.");

            }

            break;

        case LogOnThreadViolation:

            NSLog(@"WebKit Threading Violation - %s called from secondary thread", function);

            break;

        case RaiseExceptionOnThreadViolation:

            [NSException raise:@"WebKitThreadingException" format:@"%s was called from a secondary thread", function];

            break;

    }

}