binding-c/runtime/c/src/support/etch_queue_apr.c - etch - Git at Google

 /* $Id$
  *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements. See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to you under the Apache License, Version
  * 2.0 (the "License"); you may not use this file except in compliance
  * with the License. You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 /*
  * etch_queue_apr.c
  * based on apr_queue, modified by Cisco as follows:
  * timeouts were added on the push and pop waits, and functions were modified
  * to release their lock at a single exit point.
  */

 #include "apr.h"
 #include <stdio.h>
 #include <stdlib.h>

 #include "apu.h"
 #include "apr_portable.h"
 #include "apr_thread_mutex.h"
 #include "apr_thread_cond.h"
 #include "apr_errno.h"

 #include "etch_queue_apr.h"  /* Cisco */

 /* #define QUEUE_DEBUG */

 #ifdef QUEUE_DEBUG
 static void Q_DBG(char*msg, etch_apr_queue_t *q) {
     fprintf(stderr, "%ld\t#%d in %d out %d\t%s\n",
                     (size_t) apr_os_thread_current(), /* cast - Cisco */
                     q->nelts, q->in, q->out,
                     msg
                     );
     fflush(stdout);  /* Cisco */
 }
 #else
 #define Q_DBG(x,y)
 #endif


 /**
  * Detects when the etch_apr_queue_t is full. This utility function is expected
  * to be called from within critical sections, and is not threadsafe.
  */
 #define etch_apr_queue_full(queue) ((queue)->nelts == (queue)->bounds)


 /**
  * Detects when the etch_apr_queue_t is empty. This utility function is expected
  * to be called from within critical sections, and is not threadsafe.
  */
 #define etch_apr_queue_empty(queue) ((queue)->nelts == 0)


 /**
  * Callback routine that is called to destroy this
  * etch_apr_queue_t when its pool is destroyed.
  */
 static apr_status_t etch_apr_queue_destroy(void *data)
 {
     etch_apr_queue_t *queue = data;

     apr_thread_cond_destroy(queue->not_empty);
     apr_thread_cond_destroy(queue->not_full);
     apr_thread_mutex_destroy(queue->one_big_mutex);

     return APR_SUCCESS;
 }


 /**
  * Initialize the etch_apr_queue_t.
  */
 apr_status_t etch_apr_queue_create(etch_apr_queue_t **q,
                                    unsigned int queue_capacity,
                                    apr_pool_t *a)
 {
     apr_status_t rv;
     etch_apr_queue_t *queue;
     queue = apr_palloc(a, sizeof(etch_apr_queue_t));
     *q = queue;

     /* nested doesn't work ;( */
     rv = apr_thread_mutex_create(&queue->one_big_mutex,
                                  APR_THREAD_MUTEX_UNNESTED,
                                  a);
     if (rv != APR_SUCCESS)
         return rv;

     rv = apr_thread_cond_create(&queue->not_empty, a);
     if (rv != APR_SUCCESS)
         return rv;

     rv = apr_thread_cond_create(&queue->not_full, a);
     if (rv != APR_SUCCESS)
         return rv;

     /* Set all the data in the queue to NULL */
     queue->data = apr_pcalloc(a, queue_capacity * sizeof(void*));
     queue->bounds = queue_capacity;
     queue->nelts = 0;
     queue->in = 0;
     queue->out = 0;
     queue->terminated = 0;
     queue->full_waiters = 0;
     queue->empty_waiters = 0;

     apr_pool_cleanup_register(a, queue, etch_apr_queue_destroy, apr_pool_cleanup_null);

     return APR_SUCCESS;
 }


 /**
  * Push new data onto the queue. Blocks if the queue is full. Once
  * the push operation has completed, it signals other threads waiting
  * in apr_queue_pop() that they may continue consuming sockets.
  * @param timeout added by Cisco. now uses apr_thread_cond_timewait().
  * interval of time to wait. zero means forever, negative indicates no wait,
  * otherwise wait time in *microseconds*.
  * @return APR_SUCCESS, APR_EAGAIN, APR_EOF, APR_EINTR, APR_TIMEUP,
  * or some APR error
  */
 apr_status_t etch_apr_queue_push(etch_apr_queue_t *queue,
                                  apr_interval_time_t timeout,
                                  void *data)
 {
     apr_status_t rv;

     if (queue->terminated)
         rv = APR_EOF; /* no more elements ever again */
     else
     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         do
         {   if (etch_apr_queue_full(queue))
             {
                 if (!queue->terminated)
                 {
                     if (-1 == timeout)
                     {   rv = APR_EAGAIN; /* asked to not wait */
                         break;
                     }

                     queue->full_waiters++;

                     if (0 == timeout)
                         rv = apr_thread_cond_wait(queue->not_full, queue->one_big_mutex);
                     else
                         rv = apr_thread_cond_timedwait(queue->not_full, queue->one_big_mutex, timeout);

                     queue->full_waiters--;
                     if (rv != APR_SUCCESS)
                         break;
                 }

                 /* If we wake up and it's still empty, then we were interrupted */
                 if (etch_apr_queue_full(queue))
                 {
                     Q_DBG("queue full (intr)", queue);
                     rv = queue->terminated? APR_EOF: APR_EINTR;
                     break;
                 }
             }

             queue->data[queue->in] = data;
             queue->in = (queue->in + 1) % queue->bounds;
             queue->nelts++;

             if (queue->empty_waiters)
             {
                 Q_DBG("sig !empty", queue);
                 rv = apr_thread_cond_signal(queue->not_empty);
             }

         } while(0);

         apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return rv;
 }


 /**
  * Push new data onto the queue. Blocks if the queue is full. Once
  * the push operation has completed, it signals other threads waiting
  * in apr_queue_pop() that they may continue consuming sockets.
  */
 apr_status_t etch_apr_queue_trypush(etch_apr_queue_t *queue, void *data)
 {
     apr_status_t rv;

     if (queue->terminated)
         rv = APR_EOF;
     else
     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         if (etch_apr_queue_full(queue))
             rv = APR_EAGAIN;
         else
         {   queue->data[queue->in] = data;
             queue->in = (queue->in + 1) % queue->bounds;
             queue->nelts++;

             if (queue->empty_waiters)
             {
                 Q_DBG("sig !empty", queue);
                 rv  = apr_thread_cond_signal(queue->not_empty);
             }
        }

        apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return rv;
 }


 /**
  * not thread safe
  */
 unsigned int etch_apr_queue_size(etch_apr_queue_t *queue) {
     return queue->nelts;
 }


 /**
  * Retrieves the next item from the queue. If there are no
  * items available, it will block until one becomes available.
  * Once retrieved, the item is placed into the address specified by
  * 'data'.
  * @param timeout added by Cisco. now uses apr_thread_cond_timewait().
  * interval of time to wait. zero means forever, -1 means no wait,
  * -2 means don't wait and ignore queue closed indicator,
  * otherwise timeout is blocking time in microseconds.
  * @return APR_SUCCESS, APR_EAGAIN, APR_EOF, APR_EINTR, APR_TIMEUP,
  * or some APR error
  */
 apr_status_t etch_apr_queue_pop(etch_apr_queue_t *queue,
                                 apr_interval_time_t timeout,
                                 void **data)
 {
     apr_status_t rv;

     if (queue->terminated)  /* Cisco back door to clear closed queue */
     {   if (timeout != ETCHQUEUE_CLEARING_CLOSED_QUEUE)
             return APR_EOF; /* no more elements ever again */
     }

     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         do
         {   /* Keep waiting until we wake up and find that the queue is not empty. */
             if (etch_apr_queue_empty(queue))
             {
                 if (-1 == timeout)
                 {   rv = APR_EAGAIN; /* asked to not wait */
                     break;
                 }

                 if (!queue->terminated)
                 {
                     queue->empty_waiters++;

                     if (0 == timeout)
                         rv = apr_thread_cond_wait(queue->not_empty, queue->one_big_mutex);
                     else
                         rv = apr_thread_cond_timedwait(queue->not_empty, queue->one_big_mutex, timeout);

                     queue->empty_waiters--;

                     if (rv != APR_SUCCESS) /* rv will be APR_TIMEUP if timed out */
                         break;
                 }

                 /* If we wake up and it's still empty, then we were interrupted */
                 if (etch_apr_queue_empty(queue))
                 {
                     Q_DBG("queue empty (intr)", queue);
                     rv = queue->terminated? APR_EOF: APR_EINTR;
                     break;
                 }
             }

             *data = queue->data[queue->out];
             queue->nelts--;

             queue->out = (queue->out + 1) % queue->bounds;

             if (queue->full_waiters)
             {
                 Q_DBG("signal !full", queue);
                 rv = apr_thread_cond_signal(queue->not_full);
             }

         } while(0);

         apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return rv;
 }


 /**
  * Retrieves the next item from the queue. If there are no
  * items available, return APR_EAGAIN.  Once retrieved,
  * the item is placed into the address specified by 'data'.
  */
 apr_status_t etch_apr_queue_trypop(etch_apr_queue_t *queue, void **data)
 {
     apr_status_t rv;

     if (queue->terminated)
         rv = APR_EOF; /* no more elements ever again */
     else
     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         if (etch_apr_queue_empty(queue))
             rv = APR_EAGAIN;
         else
         {   *data = queue->data[queue->out];
             queue->nelts--;

             queue->out = (queue->out + 1) % queue->bounds;

             if (queue->full_waiters)
             {
                 Q_DBG("signal !full", queue);
                 rv = apr_thread_cond_signal(queue->not_full);
             }
        }

        apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return rv;
 }


 apr_status_t etch_apr_queue_interrupt_all(etch_apr_queue_t *queue)
 {
     apr_status_t rv;
     Q_DBG("intr all", queue);

     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         apr_thread_cond_broadcast(queue->not_empty);
         apr_thread_cond_broadcast(queue->not_full);

         apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return rv;
 }


 /**
  * etch_apr_queue_unsafe_interrupt_all()
  * added by Cisco to opeate when lock already held since queue lock is not nestable.
  */
 apr_status_t etch_apr_queue_unsafe_interrupt_all(etch_apr_queue_t *queue)
 {
     Q_DBG("intr all", queue);

     apr_thread_cond_broadcast(queue->not_empty);
     apr_thread_cond_broadcast(queue->not_full);

     return APR_SUCCESS;
 }


 apr_status_t etch_apr_queue_term(etch_apr_queue_t *queue)
 {
     apr_status_t rv;

     if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
     {
         /* we must hold one_big_mutex when setting this... otherwise,
          * we could end up setting it and waking everybody up just after a
          * would-be popper checks it but right before they block
          */
         queue->terminated = 1;

         apr_thread_mutex_unlock(queue->one_big_mutex);
     }

     return etch_apr_queue_interrupt_all(queue);
 }


 /**
  * added by Cisco to close queue when lock already held
  */
 apr_status_t etch_apr_queue_unsafeclose(etch_apr_queue_t *queue)
 {
     queue->terminated = 1;
     return etch_apr_queue_unsafe_interrupt_all(queue);
 }


 /**
  * added by Cisco to access lock externally
  */
 apr_status_t etch_apr_queue_lock(etch_apr_queue_t *queue)
 {
     return apr_thread_mutex_lock(queue->one_big_mutex);
 }


 /**
  * added by Cisco to access lock externally
  */
 apr_status_t etch_apr_queue_unlock(etch_apr_queue_t *queue)
 {
     return apr_thread_mutex_unlock(queue->one_big_mutex);
 }


 /**
  * etch_apr_queue_trylock()
  * added by Cisco to access lock externally
  */
 int etch_apr_queue_trylock(etch_apr_queue_t *queue)
 {
     return apr_thread_mutex_trylock(queue->one_big_mutex);
 }
	/* $Id$
	*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to you under the Apache License, Version
	* 2.0 (the "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/*
	* etch_queue_apr.c
	* based on apr_queue, modified by Cisco as follows:
	* timeouts were added on the push and pop waits, and functions were modified
	* to release their lock at a single exit point.
	*/

	#include "apr.h"
	#include <stdio.h>
	#include <stdlib.h>

	#include "apu.h"
	#include "apr_portable.h"
	#include "apr_thread_mutex.h"
	#include "apr_thread_cond.h"
	#include "apr_errno.h"

	#include "etch_queue_apr.h" /* Cisco */

	/* #define QUEUE_DEBUG */

	#ifdef QUEUE_DEBUG
	static void Q_DBG(charmsg, etch_apr_queue_t q) {
	fprintf(stderr, "%ld\t#%d in %d out %d\t%s\n",
	(size_t) apr_os_thread_current(), /* cast - Cisco */
	q->nelts, q->in, q->out,
	msg
	);
	fflush(stdout); /* Cisco */
	}
	#else
	#define Q_DBG(x,y)
	#endif


	/**
	* Detects when the etch_apr_queue_t is full. This utility function is expected
	* to be called from within critical sections, and is not threadsafe.
	*/
	#define etch_apr_queue_full(queue) ((queue)->nelts == (queue)->bounds)


	/**
	* Detects when the etch_apr_queue_t is empty. This utility function is expected
	* to be called from within critical sections, and is not threadsafe.
	*/
	#define etch_apr_queue_empty(queue) ((queue)->nelts == 0)


	/**
	* Callback routine that is called to destroy this
	* etch_apr_queue_t when its pool is destroyed.
	*/
	static apr_status_t etch_apr_queue_destroy(void *data)
	{
	etch_apr_queue_t *queue = data;

	apr_thread_cond_destroy(queue->not_empty);
	apr_thread_cond_destroy(queue->not_full);
	apr_thread_mutex_destroy(queue->one_big_mutex);

	return APR_SUCCESS;
	}


	/**
	* Initialize the etch_apr_queue_t.
	*/
	apr_status_t etch_apr_queue_create(etch_apr_queue_t **q,
	unsigned int queue_capacity,
	apr_pool_t *a)
	{
	apr_status_t rv;
	etch_apr_queue_t *queue;
	queue = apr_palloc(a, sizeof(etch_apr_queue_t));
	*q = queue;

	/* nested doesn't work ;( */
	rv = apr_thread_mutex_create(&queue->one_big_mutex,
	APR_THREAD_MUTEX_UNNESTED,
	a);
	if (rv != APR_SUCCESS)
	return rv;

	rv = apr_thread_cond_create(&queue->not_empty, a);
	if (rv != APR_SUCCESS)
	return rv;

	rv = apr_thread_cond_create(&queue->not_full, a);
	if (rv != APR_SUCCESS)
	return rv;

	/* Set all the data in the queue to NULL */
	queue->data = apr_pcalloc(a, queue_capacity * sizeof(void*));
	queue->bounds = queue_capacity;
	queue->nelts = 0;
	queue->in = 0;
	queue->out = 0;
	queue->terminated = 0;
	queue->full_waiters = 0;
	queue->empty_waiters = 0;

	apr_pool_cleanup_register(a, queue, etch_apr_queue_destroy, apr_pool_cleanup_null);

	return APR_SUCCESS;
	}


	/**
	* Push new data onto the queue. Blocks if the queue is full. Once
	* the push operation has completed, it signals other threads waiting
	* in apr_queue_pop() that they may continue consuming sockets.
	* @param timeout added by Cisco. now uses apr_thread_cond_timewait().
	* interval of time to wait. zero means forever, negative indicates no wait,
	* otherwise wait time in microseconds.
	* @return APR_SUCCESS, APR_EAGAIN, APR_EOF, APR_EINTR, APR_TIMEUP,
	* or some APR error
	*/
	apr_status_t etch_apr_queue_push(etch_apr_queue_t *queue,
	apr_interval_time_t timeout,
	void *data)
	{
	apr_status_t rv;

	if (queue->terminated)
	rv = APR_EOF; /* no more elements ever again */
	else
	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	do
	{ if (etch_apr_queue_full(queue))
	{
	if (!queue->terminated)
	{
	if (-1 == timeout)
	{ rv = APR_EAGAIN; /* asked to not wait */
	break;
	}

	queue->full_waiters++;

	if (0 == timeout)
	rv = apr_thread_cond_wait(queue->not_full, queue->one_big_mutex);
	else
	rv = apr_thread_cond_timedwait(queue->not_full, queue->one_big_mutex, timeout);

	queue->full_waiters--;
	if (rv != APR_SUCCESS)
	break;
	}

	/* If we wake up and it's still empty, then we were interrupted */
	if (etch_apr_queue_full(queue))
	{
	Q_DBG("queue full (intr)", queue);
	rv = queue->terminated? APR_EOF: APR_EINTR;
	break;
	}
	}

	queue->data[queue->in] = data;
	queue->in = (queue->in + 1) % queue->bounds;
	queue->nelts++;

	if (queue->empty_waiters)
	{
	Q_DBG("sig !empty", queue);
	rv = apr_thread_cond_signal(queue->not_empty);
	}

	} while(0);

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return rv;
	}


	/**
	* Push new data onto the queue. Blocks if the queue is full. Once
	* the push operation has completed, it signals other threads waiting
	* in apr_queue_pop() that they may continue consuming sockets.
	*/
	apr_status_t etch_apr_queue_trypush(etch_apr_queue_t queue, void data)
	{
	apr_status_t rv;

	if (queue->terminated)
	rv = APR_EOF;
	else
	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	if (etch_apr_queue_full(queue))
	rv = APR_EAGAIN;
	else
	{ queue->data[queue->in] = data;
	queue->in = (queue->in + 1) % queue->bounds;
	queue->nelts++;

	if (queue->empty_waiters)
	{
	Q_DBG("sig !empty", queue);
	rv = apr_thread_cond_signal(queue->not_empty);
	}
	}

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return rv;
	}


	/**
	* not thread safe
	*/
	unsigned int etch_apr_queue_size(etch_apr_queue_t *queue) {
	return queue->nelts;
	}


	/**
	* Retrieves the next item from the queue. If there are no
	* items available, it will block until one becomes available.
	* Once retrieved, the item is placed into the address specified by
	* 'data'.
	* @param timeout added by Cisco. now uses apr_thread_cond_timewait().
	* interval of time to wait. zero means forever, -1 means no wait,
	* -2 means don't wait and ignore queue closed indicator,
	* otherwise timeout is blocking time in microseconds.
	* @return APR_SUCCESS, APR_EAGAIN, APR_EOF, APR_EINTR, APR_TIMEUP,
	* or some APR error
	*/
	apr_status_t etch_apr_queue_pop(etch_apr_queue_t *queue,
	apr_interval_time_t timeout,
	void **data)
	{
	apr_status_t rv;

	if (queue->terminated) /* Cisco back door to clear closed queue */
	{ if (timeout != ETCHQUEUE_CLEARING_CLOSED_QUEUE)
	return APR_EOF; /* no more elements ever again */
	}

	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	do
	{ /* Keep waiting until we wake up and find that the queue is not empty. */
	if (etch_apr_queue_empty(queue))
	{
	if (-1 == timeout)
	{ rv = APR_EAGAIN; /* asked to not wait */
	break;
	}

	if (!queue->terminated)
	{
	queue->empty_waiters++;

	if (0 == timeout)
	rv = apr_thread_cond_wait(queue->not_empty, queue->one_big_mutex);
	else
	rv = apr_thread_cond_timedwait(queue->not_empty, queue->one_big_mutex, timeout);

	queue->empty_waiters--;

	if (rv != APR_SUCCESS) /* rv will be APR_TIMEUP if timed out */
	break;
	}

	/* If we wake up and it's still empty, then we were interrupted */
	if (etch_apr_queue_empty(queue))
	{
	Q_DBG("queue empty (intr)", queue);
	rv = queue->terminated? APR_EOF: APR_EINTR;
	break;
	}
	}

	*data = queue->data[queue->out];
	queue->nelts--;

	queue->out = (queue->out + 1) % queue->bounds;

	if (queue->full_waiters)
	{
	Q_DBG("signal !full", queue);
	rv = apr_thread_cond_signal(queue->not_full);
	}

	} while(0);

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return rv;
	}


	/**
	* Retrieves the next item from the queue. If there are no
	* items available, return APR_EAGAIN. Once retrieved,
	* the item is placed into the address specified by 'data'.
	*/
	apr_status_t etch_apr_queue_trypop(etch_apr_queue_t queue, void *data)
	{
	apr_status_t rv;

	if (queue->terminated)
	rv = APR_EOF; /* no more elements ever again */
	else
	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	if (etch_apr_queue_empty(queue))
	rv = APR_EAGAIN;
	else
	{ *data = queue->data[queue->out];
	queue->nelts--;

	queue->out = (queue->out + 1) % queue->bounds;

	if (queue->full_waiters)
	{
	Q_DBG("signal !full", queue);
	rv = apr_thread_cond_signal(queue->not_full);
	}
	}

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return rv;
	}


	apr_status_t etch_apr_queue_interrupt_all(etch_apr_queue_t *queue)
	{
	apr_status_t rv;
	Q_DBG("intr all", queue);

	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	apr_thread_cond_broadcast(queue->not_empty);
	apr_thread_cond_broadcast(queue->not_full);

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return rv;
	}


	/**
	* etch_apr_queue_unsafe_interrupt_all()
	* added by Cisco to opeate when lock already held since queue lock is not nestable.
	*/
	apr_status_t etch_apr_queue_unsafe_interrupt_all(etch_apr_queue_t *queue)
	{
	Q_DBG("intr all", queue);

	apr_thread_cond_broadcast(queue->not_empty);
	apr_thread_cond_broadcast(queue->not_full);

	return APR_SUCCESS;
	}


	apr_status_t etch_apr_queue_term(etch_apr_queue_t *queue)
	{
	apr_status_t rv;

	if (APR_SUCCESS == (rv = apr_thread_mutex_lock(queue->one_big_mutex)))
	{
	/* we must hold one_big_mutex when setting this... otherwise,
	* we could end up setting it and waking everybody up just after a
	* would-be popper checks it but right before they block
	*/
	queue->terminated = 1;

	apr_thread_mutex_unlock(queue->one_big_mutex);
	}

	return etch_apr_queue_interrupt_all(queue);
	}


	/**
	* added by Cisco to close queue when lock already held
	*/
	apr_status_t etch_apr_queue_unsafeclose(etch_apr_queue_t *queue)
	{
	queue->terminated = 1;
	return etch_apr_queue_unsafe_interrupt_all(queue);
	}


	/**
	* added by Cisco to access lock externally
	*/
	apr_status_t etch_apr_queue_lock(etch_apr_queue_t *queue)
	{
	return apr_thread_mutex_lock(queue->one_big_mutex);
	}


	/**
	* added by Cisco to access lock externally
	*/
	apr_status_t etch_apr_queue_unlock(etch_apr_queue_t *queue)
	{
	return apr_thread_mutex_unlock(queue->one_big_mutex);
	}


	/**
	* etch_apr_queue_trylock()
	* added by Cisco to access lock externally
	*/
	int etch_apr_queue_trylock(etch_apr_queue_t *queue)
	{
	return apr_thread_mutex_trylock(queue->one_big_mutex);
	}