1 /*

     2  * Copyright (C) 2009 Google Inc. All rights reserved.

     3  *

     4  * Redistribution and use in source and binary forms, with or without

     5  * modification, are permitted provided that the following conditions are

     6  * met:

     7  *

     8  *     * Redistributions of source code must retain the above copyright

     9  * notice, this list of conditions and the following disclaimer.

    10  *     * Redistributions in binary form must reproduce the above

    11  * copyright notice, this list of conditions and the following disclaimer

    12  * in the documentation and/or other materials provided with the

    13  * distribution.

    14  *     * Neither the name of Google Inc. nor the names of its

    15  * contributors may be used to endorse or promote products derived from

    16  * this software without specific prior written permission.

    17  *

    18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

    19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

    20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

    21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

    22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

    23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

    24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

    25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

    26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    29  */

    30 

    31 #include "config.h"

    32 

    33 #if USE(PTHREADS)

    34 

    35 #include "ThreadIdentifierDataPthreads.h"

    36 

    37 #include "Threading.h"

    38 

    39 namespace WTF {

    40 

    41 pthread_key_t ThreadIdentifierData::m_key;

    42 

    43 void clearPthreadHandleForIdentifier(ThreadIdentifier);

    44 

    45 ThreadIdentifierData::~ThreadIdentifierData()

    46 {

    47     clearPthreadHandleForIdentifier(m_identifier);

    48 }

    49 

    50 ThreadIdentifier ThreadIdentifierData::identifier()

    51 {

    52     initializeKeyOnce();

    53     ThreadIdentifierData* threadIdentifierData = static_cast<ThreadIdentifierData*>(pthread_getspecific(m_key));

    54 

    55     return threadIdentifierData ? threadIdentifierData->m_identifier : 0;

    56 }

    57 

    58 void ThreadIdentifierData::initialize(ThreadIdentifier id)

    59 {

    60     ASSERT(!identifier());

    61 

    62     initializeKeyOnce();

    63     pthread_setspecific(m_key, new ThreadIdentifierData(id));

    64 }

    65 

    66 void ThreadIdentifierData::destruct(void* data)

    67 {

    68     ThreadIdentifierData* threadIdentifierData = static_cast<ThreadIdentifierData*>(data);

    69     ASSERT(threadIdentifierData);

    70 

    71     if (threadIdentifierData->m_isDestroyedOnce) {

    72         delete threadIdentifierData;

    73         return;

    74     }

    75 

    76     threadIdentifierData->m_isDestroyedOnce = true;

    77     // Re-setting the value for key causes another destruct() call after all other thread-specific destructors were called.

    78     pthread_setspecific(m_key, threadIdentifierData);

    79 }

    80 

    81 void ThreadIdentifierData::initializeKeyOnceHelper()

    82 {

    83     if (pthread_key_create(&m_key, destruct))

    84         CRASH();

    85 }

    86 

    87 void ThreadIdentifierData::initializeKeyOnce()

    88 {

    89     static pthread_once_t onceControl = PTHREAD_ONCE_INIT;

    90     if (pthread_once(&onceControl, initializeKeyOnceHelper))

    91         CRASH();

    92 }

    93 

    94 } // namespace WTF

    95 

    96 #endif // USE(PTHREADS)

    97