Libc-498.1.1.tar.gz

[apple/libc.git] / pthreads / pthread.c

/*
 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright 1996 1995 by Open Software Foundation, Inc. 1997 1996 1995 1994 1993 1992 1991  
 *              All Rights Reserved 
 *  
 * Permission to use, copy, modify, and distribute this software and 
 * its documentation for any purpose and without fee is hereby granted, 
 * provided that the above copyright notice appears in all copies and 
 * that both the copyright notice and this permission notice appear in 
 * supporting documentation. 
 *  
 * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
 * FOR A PARTICULAR PURPOSE. 
 *  
 * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 
 * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 
 * 
 */
/*
 * MkLinux
 */

/*
 * POSIX Pthread Library
 */

#include "pthread_internals.h"
#include "pthread_workqueue.h"

#include <assert.h>
#include <stdio.h>      /* For printf(). */
#include <stdlib.h>
#include <errno.h>      /* For __mach_errno_addr() prototype. */
#include <signal.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/queue.h>
#include <machine/vmparam.h>
#include <mach/vm_statistics.h>
#define __APPLE_API_PRIVATE
#include <machine/cpu_capabilities.h>
#include <libkern/OSAtomic.h>
#if defined(__ppc__)
#include <libkern/OSCrossEndian.h>
#endif


#ifndef BUILDING_VARIANT /* [ */

__private_extern__ struct __pthread_list __pthread_head = TAILQ_HEAD_INITIALIZER(__pthread_head);



/* Per-thread kernel support */
extern void _pthread_set_self(pthread_t);
extern void mig_init(int);
static int _pthread_create_pthread_onstack(pthread_attr_t *attrs, void **stack, pthread_t *thread);
static kern_return_t _pthread_free_pthread_onstack(pthread_t t, int freestruct, int termthread);
void _pthread_struct_init(pthread_t t, const pthread_attr_t *attrs, void * stack, size_t stacksize, int kernalloc, int nozero);
static void _pthread_tsd_reinit(pthread_t t);
static int  _new_pthread_create_suspended(pthread_t *thread, 
               const pthread_attr_t *attr,
               void *(*start_routine)(void *), 
               void *arg,
                int create_susp);

/* Get CPU capabilities from the kernel */
__private_extern__ void _init_cpu_capabilities(void);

/* Needed to tell the malloc subsystem we're going multithreaded */
extern void set_malloc_singlethreaded(int);

/* Used when we need to call into the kernel with no reply port */
extern pthread_lock_t reply_port_lock;
int _pthread_find_thread(pthread_t thread);

/* Mach message used to notify that a thread needs to be reaped */

typedef struct _pthread_reap_msg_t {
        mach_msg_header_t header;
        pthread_t thread;
        mach_msg_trailer_t trailer;
} pthread_reap_msg_t;

/* We'll implement this when the main thread is a pthread */
/* Use the local _pthread struct to avoid malloc before our MiG reply port is set */
static struct _pthread _thread = {0};

/* This global should be used (carefully) by anyone needing to know if a 
** pthread has been created.
*/
int __is_threaded = 0;
/* _pthread_count is protected by _pthread_list_lock */
static int _pthread_count = 1;
int __unix_conforming = 0;
__private_extern__ size_t pthreadsize = 0;

/* under rosetta we will use old style creation of threads */
static int __oldstyle = 0;

__private_extern__ pthread_lock_t _pthread_list_lock = LOCK_INITIALIZER;

/* Same implementation as LOCK, but without the __is_threaded check */
int _spin_tries = 0;
__private_extern__ void _spin_lock_retry(pthread_lock_t *lock)
{ 
        int tries = _spin_tries;
        do {
                if (tries-- > 0)
                        continue;
                syscall_thread_switch(THREAD_NULL, SWITCH_OPTION_DEPRESS, 1);
                tries = _spin_tries;
        } while(!_spin_lock_try(lock));
}

extern mach_port_t thread_recycle_port;

/* These are used to keep track of a semaphore pool shared by mutexes and condition
** variables.
*/

static semaphore_t *sem_pool = NULL;
static int sem_pool_count = 0;
static int sem_pool_current = 0;
static pthread_lock_t sem_pool_lock = LOCK_INITIALIZER;

static int default_priority;
static int max_priority;
static int min_priority;
static int pthread_concurrency;

static OSSpinLock __workqueue_list_lock = OS_SPINLOCK_INIT;

static void _pthread_exit(pthread_t self, void *value_ptr);
int _pthread_setcancelstate_internal(int state, int *oldstate, int conforming);
static void _pthread_setcancelstate_exit(pthread_t self, void  *value_ptr, int conforming);
static pthread_attr_t _pthread_attr_default = {0};
static void _pthread_workq_init(pthread_workqueue_t wq, const pthread_workqueue_attr_t * attr);
static int handle_removeitem(pthread_workqueue_t workq, pthread_workitem_t item);
static int kernel_workq_setup = 0;
static volatile int32_t kernel_workq_count = 0;
static volatile unsigned int user_workq_count = 0; 
#define KERNEL_WORKQ_ELEM_MAX   64              /* Max number of elements in the kerrel */
static int wqreadyprio = 0;     /* current highest prio queue ready with items */

__private_extern__ struct __pthread_workitem_pool __pthread_workitem_pool_head = TAILQ_HEAD_INITIALIZER(__pthread_workitem_pool_head);
__private_extern__ struct __pthread_workqueue_pool __pthread_workqueue_pool_head = TAILQ_HEAD_INITIALIZER(__pthread_workqueue_pool_head);

struct _pthread_workqueue_head __pthread_workq0_head;
struct _pthread_workqueue_head __pthread_workq1_head;
struct _pthread_workqueue_head __pthread_workq2_head;
struct _pthread_workqueue_head __pthread_workq3_head;
struct _pthread_workqueue_head __pthread_workq4_head;
pthread_workqueue_head_t __pthread_wq_head_tbl[WQ_NUM_PRIO_QS] = {&__pthread_workq0_head, &__pthread_workq1_head, &__pthread_workq2_head, &__pthread_workq3_head, &__pthread_workq4_head};

static void workqueue_list_lock(void);
static void workqueue_list_unlock(void);
static int valid_workq(pthread_workqueue_t);
static void pick_nextworkqueue_droplock(void);
static int post_nextworkitem(pthread_workqueue_t workq);
static void _pthread_workq_return(pthread_t self);
static pthread_workqueue_attr_t _pthread_wq_attr_default = {0};
void _pthread_wqthread(pthread_t self, mach_port_t kport, void * stackaddr, pthread_workitem_t item, int reuse);
extern void start_wqthread(pthread_t self, mach_port_t kport, void * stackaddr, pthread_workitem_t item, int reuse);
extern void thread_start(pthread_t self, mach_port_t kport, void *(*fun)(void *), void * funarg, size_t stacksize, int flags);
static pthread_workitem_t alloc_workitem(void);
static void free_workitem(pthread_workitem_t);
static pthread_workqueue_t alloc_workqueue(void);
static void free_workqueue(pthread_workqueue_t);
static int _pthread_work_internal_init(void);
static void workqueue_exit(pthread_t self, pthread_workqueue_t workq, pthread_workitem_t item);

/* workq_ops commands */
#define WQOPS_QUEUE_ADD 1
#define WQOPS_QUEUE_REMOVE 2
#define WQOPS_THREAD_RETURN 4

/*
 * Flags filed passed to bsdthread_create and back in pthread_start 
31  <---------------------------------> 0
_________________________________________
| flags(8) | policy(8) | importance(16) |
-----------------------------------------
*/
void _pthread_start(pthread_t self, mach_port_t kport, void *(*fun)(void *), void * funarg, size_t stacksize, unsigned int flags);

#define PTHREAD_START_CUSTOM    0x01000000
#define PTHREAD_START_SETSCHED  0x02000000
#define PTHREAD_START_DETACHED  0x04000000
#define PTHREAD_START_POLICY_BITSHIFT 16
#define PTHREAD_START_POLICY_MASK 0xff
#define PTHREAD_START_IMPORTANCE_MASK 0xffff

extern pthread_t __bsdthread_create(void (*func)(void *), void * func_arg, void * stack, pthread_t  thread, unsigned int flags);
extern int __bsdthread_terminate(void * freeaddr, size_t freesize, mach_port_t kport, mach_port_t joinsem);

#if defined(__ppc__) || defined(__ppc64__)
static const vm_address_t PTHREAD_STACK_HINT = 0xF0000000;
#elif defined(__i386__) || defined(__x86_64__)
static const vm_address_t PTHREAD_STACK_HINT = 0xB0000000;
#else
#error Need to define a stack address hint for this architecture
#endif

/* Set the base address to use as the stack pointer, before adjusting due to the ABI
 * The guardpages for stackoverflow protection is also allocated here
 * If the stack was already allocated(stackaddr in attr)  then there are no guardpages 
 * set up for the thread
 */

static int
_pthread_allocate_stack(pthread_attr_t *attrs, void **stack)
{
    kern_return_t kr;
    vm_address_t stackaddr;
    size_t guardsize;

    assert(attrs->stacksize >= PTHREAD_STACK_MIN);
    if (attrs->stackaddr != NULL) {
        /* No guard pages setup in this case */
        assert(((uintptr_t)attrs->stackaddr % vm_page_size) == 0);
        *stack = attrs->stackaddr;
         return 0;
    }

    guardsize = attrs->guardsize;
    stackaddr = PTHREAD_STACK_HINT;
    kr = vm_map(mach_task_self(), &stackaddr,
                        attrs->stacksize + guardsize,
                        vm_page_size-1,
                        VM_MAKE_TAG(VM_MEMORY_STACK)| VM_FLAGS_ANYWHERE , MEMORY_OBJECT_NULL,
                        0, FALSE, VM_PROT_DEFAULT, VM_PROT_ALL,
                        VM_INHERIT_DEFAULT);
    if (kr != KERN_SUCCESS)
        kr = vm_allocate(mach_task_self(),
                                        &stackaddr, attrs->stacksize + guardsize,
                                        VM_MAKE_TAG(VM_MEMORY_STACK)| VM_FLAGS_ANYWHERE);
    if (kr != KERN_SUCCESS) {
        return EAGAIN;
    }
     /* The guard page is at the lowest address */
     /* The stack base is the highest address */
    if (guardsize)
        kr = vm_protect(mach_task_self(), stackaddr, guardsize, FALSE, VM_PROT_NONE);
    *stack = (void *)(stackaddr + attrs->stacksize + guardsize);
        return 0;
}

static int
_pthread_create_pthread_onstack(pthread_attr_t *attrs, void **stack, pthread_t *thread)
{
    kern_return_t kr;
        pthread_t t;
    vm_address_t stackaddr;
    size_t guardsize, allocsize;

        assert(attrs->stacksize >= PTHREAD_STACK_MIN);

    if (attrs->stackaddr != NULL) {
        /* No guard pages setup in this case */
                assert(((uintptr_t)attrs->stackaddr % vm_page_size) == 0);
                *stack = attrs->stackaddr;
                t = (pthread_t)malloc(pthreadsize);
                _pthread_struct_init(t, attrs, attrs->stackaddr, 0, 0, 0);
                t->freeStackOnExit = 0;
                t->freeaddr = 0;
                t->freesize = 0;
                *thread = t;
                return 0;
        }

    guardsize = attrs->guardsize;
        allocsize = attrs->stacksize + guardsize + pthreadsize;
    stackaddr = PTHREAD_STACK_HINT;
    kr = vm_map(mach_task_self(), &stackaddr,
                        allocsize,
                        vm_page_size-1,
                        VM_MAKE_TAG(VM_MEMORY_STACK)| VM_FLAGS_ANYWHERE , MEMORY_OBJECT_NULL,
                        0, FALSE, VM_PROT_DEFAULT, VM_PROT_ALL,
                        VM_INHERIT_DEFAULT);
    if (kr != KERN_SUCCESS)
        kr = vm_allocate(mach_task_self(),
                                        &stackaddr, allocsize,
                                        VM_MAKE_TAG(VM_MEMORY_STACK)| VM_FLAGS_ANYWHERE);
    if (kr != KERN_SUCCESS) {
        return EAGAIN;
    }
     /* The guard page is at the lowest address */
     /* The stack base is the highest address */
    if (guardsize)
        kr = vm_protect(mach_task_self(), stackaddr, guardsize, FALSE, VM_PROT_NONE);


        *stack = (void *)(stackaddr + attrs->stacksize + guardsize);

        t = (pthread_t)(stackaddr + attrs->stacksize + guardsize);
        _pthread_struct_init(t, attrs, *stack, 0, 0, 1);
        t->kernalloc = 0;
        t->freesize = allocsize;
        t->freeaddr = (void *)stackaddr;
        t->freeStackOnExit = 1;
        *thread = t;

    return 0;
}

static kern_return_t
_pthread_free_pthread_onstack(pthread_t t, int freestruct, int termthread)
{
        kern_return_t res = 0;
        vm_address_t freeaddr;
        size_t freesize;
        task_t self = mach_task_self();
        int thread_count;
        mach_port_t kport;
        semaphore_t joinsem = SEMAPHORE_NULL;

#if WQ_TRACE
        __kdebug_trace(0x900001c, freestruct, termthread, 0, 0, 0);
#endif
        kport = t->kernel_thread;
        joinsem = t->joiner_notify;

        if (t->freeStackOnExit) {
                freeaddr = (vm_address_t)t->freeaddr;
                if (freestruct)
                        freesize = t->stacksize + t->guardsize + pthreadsize;
                else
                        freesize = t->stacksize + t->guardsize;
                if (termthread) {
                        mig_dealloc_reply_port(MACH_PORT_NULL);
                        LOCK(_pthread_list_lock);
                        if (freestruct != 0) {
                                TAILQ_REMOVE(&__pthread_head, t, plist);
                                /* if parent has not returned from create yet keep pthread_t */
#if WQ_TRACE
                                __kdebug_trace(0x9000010, t, 0, 0, 1, 0);
#endif
                                if (t->parentcheck == 0)
                                        freesize -= pthreadsize;
                        }
                        t->childexit = 1;
                        thread_count = --_pthread_count;
                        UNLOCK(_pthread_list_lock);

#if WQ_TRACE
                __kdebug_trace(0x9000020, freeaddr, freesize, kport, 1, 0);
#endif
                        if (thread_count <=0)
                                exit(0);
                        else
                                __bsdthread_terminate(freeaddr, freesize, kport, joinsem);
                        abort();
                } else  {
#if WQ_TRACE
                        __kdebug_trace(0x9000024, freeaddr, freesize, 0, 1, 0);
#endif
                        res = vm_deallocate(mach_task_self(), freeaddr, freesize);
                }
        } else {
                if (termthread) {
                        mig_dealloc_reply_port(MACH_PORT_NULL);
                        LOCK(_pthread_list_lock);
                        if (freestruct != 0) {
                                TAILQ_REMOVE(&__pthread_head, t, plist);
#if WQ_TRACE
                                __kdebug_trace(0x9000010, t, 0, 0, 2, 0);
#endif
                        }
                        thread_count = --_pthread_count;
                        t->childexit = 1;
                        UNLOCK(_pthread_list_lock);

                        if (freestruct)  {
#if WQ_TRACE
                __kdebug_trace(0x9000008, t, 0, 0, 2, 0);
#endif
                                free(t);
                        }

                        freeaddr = 0;
                        freesize = 0;
#if WQ_TRACE
                __kdebug_trace(0x9000020, 0, 0, kport, 2, 0);
#endif

                        if (thread_count <=0)
                                exit(0);
                        else
                                __bsdthread_terminate(NULL, 0, kport, joinsem);
                        abort();
                } else if (freestruct) {
                       t->sig = _PTHREAD_NO_SIG;
#if WQ_TRACE
                        __kdebug_trace(0x9000024, t, 0, 0, 2, 0);
#endif
                        free(t);
                }
        }
        return(res);
} 



/*
 * Destroy a thread attribute structure
 */
int       
pthread_attr_destroy(pthread_attr_t *attr)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                attr->sig = 0;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Get the 'detach' state from a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_getdetachstate(const pthread_attr_t *attr, 
                            int *detachstate)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                *detachstate = attr->detached;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Get the 'inherit scheduling' info from a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_getinheritsched(const pthread_attr_t *attr, 
                             int *inheritsched)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                *inheritsched = attr->inherit;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Get the scheduling parameters from a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_getschedparam(const pthread_attr_t *attr, 
                           struct sched_param *param)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                *param = attr->param;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Get the scheduling policy from a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_getschedpolicy(const pthread_attr_t *attr, 
                            int *policy)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                *policy = attr->policy;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/* Retain the existing stack size of 512K and not depend on Main thread default stack size */
static const size_t DEFAULT_STACK_SIZE = (512*1024);
/*
 * Initialize a thread attribute structure to default values.
 */
int       
pthread_attr_init(pthread_attr_t *attr)
{
        attr->stacksize = DEFAULT_STACK_SIZE;
        attr->stackaddr = NULL;
        attr->sig = _PTHREAD_ATTR_SIG;
        attr->param.sched_priority = default_priority;
        attr->param.quantum = 10; /* quantum isn't public yet */
        attr->detached = PTHREAD_CREATE_JOINABLE;
        attr->inherit = _PTHREAD_DEFAULT_INHERITSCHED;
        attr->policy = _PTHREAD_DEFAULT_POLICY;
        attr->freeStackOnExit = 1;
        attr->fastpath = 1;
        attr->schedset = 0;
        attr->guardsize = vm_page_size;
        return (0);
}

/*
 * Set the 'detach' state in a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_setdetachstate(pthread_attr_t *attr, 
                            int detachstate)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                if ((detachstate == PTHREAD_CREATE_JOINABLE) ||
                    (detachstate == PTHREAD_CREATE_DETACHED))
                {
                        attr->detached = detachstate;
                        return (0);
                } else
                {
                        return (EINVAL);
                }
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Set the 'inherit scheduling' state in a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_setinheritsched(pthread_attr_t *attr, 
                             int inheritsched)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                if ((inheritsched == PTHREAD_INHERIT_SCHED) ||
                    (inheritsched == PTHREAD_EXPLICIT_SCHED))
                {
                        attr->inherit = inheritsched;
                        return (0);
                } else
                {
                        return (EINVAL);
                }
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Set the scheduling paramters in a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_setschedparam(pthread_attr_t *attr, 
                           const struct sched_param *param)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                /* TODO: Validate sched_param fields */
                attr->param = *param;
                attr->schedset = 1;
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Set the scheduling policy in a thread attribute structure.
 * Note: written as a helper function for info hiding
 */
int       
pthread_attr_setschedpolicy(pthread_attr_t *attr, 
                            int policy)
{
        if (attr->sig == _PTHREAD_ATTR_SIG)
        {
                if ((policy == SCHED_OTHER) ||
                    (policy == SCHED_RR) ||
                    (policy == SCHED_FIFO))
                {
                        attr->policy = policy;
                        attr->schedset = 1;
                        return (0);
                } else
                {
                        return (EINVAL);
                }
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

/*
 * Set the scope for the thread.
 * We currently only provide PTHREAD_SCOPE_SYSTEM
 */
int
pthread_attr_setscope(pthread_attr_t *attr,
                            int scope)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        if (scope == PTHREAD_SCOPE_SYSTEM) {
            /* No attribute yet for the scope */
            return (0);
        } else if (scope == PTHREAD_SCOPE_PROCESS) {
            return (ENOTSUP);
        }
    }
    return (EINVAL); /* Not an attribute structure! */
}

/*
 * Get the scope for the thread.
 * We currently only provide PTHREAD_SCOPE_SYSTEM
 */
int
pthread_attr_getscope(const pthread_attr_t *attr,
                            int *scope)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        *scope = PTHREAD_SCOPE_SYSTEM;
        return (0);
    }
    return (EINVAL); /* Not an attribute structure! */
}

/* Get the base stack address of the given thread */
int
pthread_attr_getstackaddr(const pthread_attr_t *attr, void **stackaddr)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        *stackaddr = attr->stackaddr;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int
pthread_attr_setstackaddr(pthread_attr_t *attr, void *stackaddr)
{
    if ((attr->sig == _PTHREAD_ATTR_SIG) && (((uintptr_t)stackaddr % vm_page_size) == 0)) {
        attr->stackaddr = stackaddr;
        attr->freeStackOnExit = 0;
        attr->fastpath = 0;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int
pthread_attr_getstacksize(const pthread_attr_t *attr, size_t *stacksize)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        *stacksize = attr->stacksize;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int
pthread_attr_setstacksize(pthread_attr_t *attr, size_t stacksize)
{
    if ((attr->sig == _PTHREAD_ATTR_SIG) && ((stacksize % vm_page_size) == 0) && (stacksize >= PTHREAD_STACK_MIN)) {
        attr->stacksize = stacksize;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int
pthread_attr_getstack(const pthread_attr_t *attr, void **stackaddr, size_t * stacksize)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        *stackaddr = (void *)((uintptr_t)attr->stackaddr - attr->stacksize);
        *stacksize = attr->stacksize;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

/* By SUSV spec, the stackaddr is the base address, the lowest addressable 
 * byte address. This is not the same as in pthread_attr_setstackaddr.
 */
int
pthread_attr_setstack(pthread_attr_t *attr, void *stackaddr, size_t stacksize)
{
    if ((attr->sig == _PTHREAD_ATTR_SIG) && 
        (((uintptr_t)stackaddr % vm_page_size) == 0) && 
         ((stacksize % vm_page_size) == 0) && (stacksize >= PTHREAD_STACK_MIN)) {
                attr->stackaddr = (void *)((uintptr_t)stackaddr + stacksize);
                attr->stacksize = stacksize;
                attr->freeStackOnExit = 0;
                attr->fastpath = 0;
                return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}


/*
 * Set the guardsize attribute in the attr.
 */
int
pthread_attr_setguardsize(pthread_attr_t *attr,
                            size_t guardsize)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        /* Guardsize of 0 is valid, ot means no guard */
        if ((guardsize % vm_page_size) == 0) {
                attr->guardsize = guardsize;
                attr->fastpath = 0;
            return (0);
        } else
                return(EINVAL);
    }
    return (EINVAL); /* Not an attribute structure! */
}

/*
 * Get the guardsize attribute in the attr.
 */
int
pthread_attr_getguardsize(const pthread_attr_t *attr,
                            size_t *guardsize)
{
    if (attr->sig == _PTHREAD_ATTR_SIG) {
        *guardsize = attr->guardsize;
        return (0);
    }
    return (EINVAL); /* Not an attribute structure! */
}


/*
 * Create and start execution of a new thread.
 */

static void
_pthread_body(pthread_t self)
{
    _pthread_set_self(self);
    _pthread_exit(self, (self->fun)(self->arg));
}

void
_pthread_start(pthread_t self, mach_port_t kport, void *(*fun)(void *), void * funarg, size_t stacksize, unsigned int pflags)
{
        int ret;
#if WQ_DEBUG
        pthread_t pself;
#endif
        pthread_attr_t *attrs = &_pthread_attr_default;
        char * stackaddr;

        if ((pflags & PTHREAD_START_CUSTOM) == 0) {
                stackaddr = self;
                _pthread_struct_init(self, attrs, stackaddr,  stacksize, 1, 1);
                LOCK(_pthread_list_lock);
                if (pflags & PTHREAD_START_SETSCHED) {
                        self->policy = ((pflags >> PTHREAD_START_POLICY_BITSHIFT) & PTHREAD_START_POLICY_MASK);
                        self->param.sched_priority = (pflags & PTHREAD_START_IMPORTANCE_MASK);
                }
                /* These are not joinable threads */
                if ((pflags & PTHREAD_START_DETACHED) == PTHREAD_START_DETACHED)  {
                        self->detached &= ~PTHREAD_CREATE_JOINABLE;
                        self->detached |= PTHREAD_CREATE_DETACHED;
                }
        }  else 
                LOCK(_pthread_list_lock);
        self->kernel_thread = kport;
        self->fun = fun;
        self->arg = funarg;
        
        /* Add to the pthread list */
        if (self->parentcheck == 0) {
                TAILQ_INSERT_TAIL(&__pthread_head, self, plist);
#if WQ_TRACE
                __kdebug_trace(0x900000c, self, 0, 0, 3, 0);
#endif
                _pthread_count++;
        }
        self->childrun = 1;
        UNLOCK(_pthread_list_lock);
#if defined(__i386__) || defined(__x86_64__)
        _pthread_set_self(self);
#endif

#if WQ_DEBUG
        pself = pthread_self();
        if (self != pself)
                abort();
#endif
#if WQ_TRACE
        __kdebug_trace(0x9000030, self, pflags, 0, 0, 0);
#endif

        _pthread_exit(self, (self->fun)(self->arg));
}

int
_pthread_create(pthread_t t,
                const pthread_attr_t *attrs,
                void *stack,
                const mach_port_t kernel_thread)
{
        int res;
        res = 0;
        
        do
        {
                memset(t, 0, sizeof(*t));
                t->newstyle = 0;
                t->schedset = 0;
                t->kernalloc = 0;
                t->tsd[0] = t;
                t->max_tsd_key = 0;
                t->wqthread = 0;
                t->cur_workq = 0;
                t->cur_workitem = 0;
                t->stacksize = attrs->stacksize;
                t->stackaddr = (void *)stack;
                t->guardsize = attrs->guardsize;
                t->kernel_thread = kernel_thread;
                t->detached = attrs->detached;
                t->inherit = attrs->inherit;
                t->policy = attrs->policy;
                t->param = attrs->param;
                t->freeStackOnExit = attrs->freeStackOnExit;
                t->mutexes = (struct _pthread_mutex *)NULL;
                t->sig = _PTHREAD_SIG;
                t->reply_port = MACH_PORT_NULL;
                t->cthread_self = NULL;
                LOCK_INIT(t->lock);
                t->plist.tqe_next = (struct _pthread *)0;
                t->plist.tqe_prev = (struct _pthread **)0;
                t->cancel_state = PTHREAD_CANCEL_ENABLE | PTHREAD_CANCEL_DEFERRED;
                t->__cleanup_stack = (struct __darwin_pthread_handler_rec *)NULL;
                t->death = SEMAPHORE_NULL;

                if (kernel_thread != MACH_PORT_NULL)
                        pthread_setschedparam(t, t->policy, &t->param);
        } while (0);
        return (res);
}

void
_pthread_struct_init(pthread_t t, const pthread_attr_t *attrs, void * stack, size_t stacksize, int kernalloc, int nozero)
{
        mach_vm_offset_t stackaddr = (mach_vm_offset_t)stack;

                if (nozero == 0) {
                        memset(t, 0, sizeof(*t));
                        t->plist.tqe_next = (struct _pthread *)0;
                        t->plist.tqe_prev = (struct _pthread **)0;
                }
                t->schedset = attrs->schedset;
                t->tsd[0] = t;
                if (kernalloc != 0) {
                        stackaddr = (mach_vm_offset_t)t;

                        /* if allocated from kernel set values appropriately */
                        t->stacksize = stacksize;
                        t->stackaddr = stackaddr;
                        t->freeStackOnExit = 1;
                        t->freeaddr = stackaddr - stacksize - vm_page_size;
                        t->freesize = pthreadsize + stacksize + vm_page_size;
                } else {
                        t->stacksize = attrs->stacksize;
                        t->stackaddr = (void *)stack;
                }
                t->guardsize = attrs->guardsize;
                t->detached = attrs->detached;
                t->inherit = attrs->inherit;
                t->policy = attrs->policy;
                t->param = attrs->param;
                t->mutexes = (struct _pthread_mutex *)NULL;
                t->sig = _PTHREAD_SIG;
                t->reply_port = MACH_PORT_NULL;
                t->cthread_self = NULL;
                LOCK_INIT(t->lock);
                t->cancel_state = PTHREAD_CANCEL_ENABLE | PTHREAD_CANCEL_DEFERRED;
                t->__cleanup_stack = (struct __darwin_pthread_handler_rec *)NULL;
                t->death = SEMAPHORE_NULL;
                t->newstyle = 1;
                t->kernalloc = kernalloc;
                t->wqthread = 0;
                t->cur_workq = 0;
                t->cur_workitem = 0;
                t->max_tsd_key = 0;
}

static void
_pthread_tsd_reinit(pthread_t t)
{
        bzero(&t->tsd[1], (_INTERNAL_POSIX_THREAD_KEYS_END-1) * sizeof(void *));
}


/* Need to deprecate this in future */
int
_pthread_is_threaded(void)
{
    return __is_threaded;
}

/* Non portable public api to know whether this process has(had) atleast one thread 
 * apart from main thread. There could be race if there is a thread in the process of
 * creation at the time of call . It does not tell whether there are more than one thread
 * at this point of time.
 */
int
pthread_is_threaded_np(void)
{
    return (__is_threaded);
}

mach_port_t
pthread_mach_thread_np(pthread_t t)
{
        mach_port_t kport = MACH_PORT_NULL;

        if (_pthread_lookup_thread(t, &kport, 0) != 0)
                return(NULL);

        return(kport);
}

pthread_t pthread_from_mach_thread_np(mach_port_t kernel_thread) 
{
    struct _pthread * p = NULL;

        /* No need to wait as mach port is already known */
    LOCK(_pthread_list_lock);
    TAILQ_FOREACH(p, &__pthread_head, plist) {
        if (p->kernel_thread == kernel_thread) 
                        break;
    }
    UNLOCK(_pthread_list_lock);     
    return p;
}

size_t
pthread_get_stacksize_np(pthread_t t)
{
        int ret;
        size_t size = 0;

        if (t == NULL)
                return(ESRCH);
        
        LOCK(_pthread_list_lock);

        if ((ret = _pthread_find_thread(t)) != 0) {
                UNLOCK(_pthread_list_lock);
                return(ret);
        }
        size = t->stacksize;
        UNLOCK(_pthread_list_lock);
        return(size);
}

void *
pthread_get_stackaddr_np(pthread_t t)
{
        int ret;
        void * addr = NULL;

        if (t == NULL)
                return(ESRCH);
        
        LOCK(_pthread_list_lock);

        if ((ret = _pthread_find_thread(t)) != 0) {
                UNLOCK(_pthread_list_lock);
                return(ret);
        }
        addr = t->stackaddr;
        UNLOCK(_pthread_list_lock);

        return(addr);
}

mach_port_t
_pthread_reply_port(pthread_t t)
{
    return t->reply_port;
}


/* returns non-zero if the current thread is the main thread */
int
pthread_main_np(void)
{
        pthread_t self = pthread_self();

        return ((self->detached & _PTHREAD_CREATE_PARENT) == _PTHREAD_CREATE_PARENT);
}

static int       
_new_pthread_create_suspended(pthread_t *thread, 
               const pthread_attr_t *attr,
               void *(*start_routine)(void *), 
               void *arg,
                int create_susp)
{
        pthread_attr_t *attrs;
        void *stack;
        int error;
        unsigned int flags;
        pthread_t t;
        kern_return_t kern_res;
        mach_port_t kernel_thread = MACH_PORT_NULL;
        int needresume;
        task_t self = mach_task_self();
        int kernalloc = 0;
        int susp = create_susp;

        if ((attrs = (pthread_attr_t *)attr) == (pthread_attr_t *)NULL)
        {                       /* Set up default paramters */
                attrs = &_pthread_attr_default;
        } else if (attrs->sig != _PTHREAD_ATTR_SIG) {
            return EINVAL;
        }
        error = 0;

        if (((attrs->policy != _PTHREAD_DEFAULT_POLICY)  || 
                (attrs->param.sched_priority != default_priority)) && (create_susp == 0)) {
                needresume = 1; 
                susp = 1;       
        } else 
                needresume = 0;

        /* In default policy (ie SCHED_OTHER) only sched_priority is used. Check for
         * any change in priority or policy is needed here.
         */
        if ((__oldstyle == 1) || (create_susp != 0)) {
                /* Rosetta or pthread_create_suspended() */
                /* running under rosetta */
                /* Allocate a stack for the thread */
#if WQ_TRACE
                __kdebug_trace(0x9000000, create_susp, 0, 0, 0, 0);
#endif
                if ((error = _pthread_allocate_stack(attrs, &stack)) != 0) {
                        return(error);
                }
                t = (pthread_t)malloc(sizeof(struct _pthread));
                *thread = t;
                if (susp) {
                        /* Create the Mach thread for this thread */
                        PTHREAD_MACH_CALL(thread_create(self, &kernel_thread), kern_res);
                        if (kern_res != KERN_SUCCESS)
                        {
                                printf("Can't create thread: %d\n", kern_res);
                                return(EINVAL);
                        }
                }
                if ((error = _pthread_create(t, attrs, stack, kernel_thread)) != 0)
                {
                        return(error);
                }
                set_malloc_singlethreaded(0);
                __is_threaded = 1;

                /* Send it on it's way */
                t->arg = arg;
                t->fun = start_routine;
                t->newstyle = 0;
                /* Now set it up to execute */
                LOCK(_pthread_list_lock);
                TAILQ_INSERT_TAIL(&__pthread_head, t, plist);
#if WQ_TRACE
                __kdebug_trace(0x900000c, t, 0, 0, 4, 0);
#endif
                _pthread_count++;
                UNLOCK(_pthread_list_lock);
                _pthread_setup(t, _pthread_body, stack, susp, needresume);
                return(0);
        } else {

                flags = 0;
                if (attrs->fastpath == 1)
                        kernalloc = 1;

                if (attrs->detached == PTHREAD_CREATE_DETACHED)
                                flags |= PTHREAD_START_DETACHED;
                if (attrs->schedset != 0) {
                        flags |= PTHREAD_START_SETSCHED;
                        flags |= ((attrs->policy & PTHREAD_START_POLICY_MASK) << PTHREAD_START_POLICY_BITSHIFT);
                        flags |= (attrs->param.sched_priority & PTHREAD_START_IMPORTANCE_MASK);
                } 

                set_malloc_singlethreaded(0);
                __is_threaded = 1;

                if (kernalloc == 0) {
                        /* Allocate a stack for the thread */
                        flags |= PTHREAD_START_CUSTOM;
                        if ((error = _pthread_create_pthread_onstack(attrs, &stack, &t)) != 0) {
                                return(error);
                        }
                        /* Send it on it's way */
                        t->arg = arg;
                        t->fun = start_routine;
                        t->newstyle = 1;

#if WQ_TRACE
                __kdebug_trace(0x9000004, t, flags, 0, 0, 0);
#endif
                        
                        if ((t = __bsdthread_create(start_routine, arg, stack, t, flags)) == -1) {
                                _pthread_free_pthread_onstack(t, 1, 0);
                                return (EAGAIN);
                        }
                        LOCK(_pthread_list_lock);
                        t->parentcheck = 1;
                        if ((t->childexit != 0) && ((t->detached & PTHREAD_CREATE_DETACHED) == PTHREAD_CREATE_DETACHED)) {
                                /* detached child exited, mop up */
                                UNLOCK(_pthread_list_lock);
#if WQ_TRACE
                        __kdebug_trace(0x9000008, t, 0, 0, 1, 0);
#endif
                                free(t);
                        } else if (t->childrun == 0) {
                                TAILQ_INSERT_TAIL(&__pthread_head, t, plist);
                                _pthread_count++;
#if WQ_TRACE
                                __kdebug_trace(0x900000c, t, 0, 0, 1, 0);
#endif
                                UNLOCK(_pthread_list_lock);
                        } else 
                                UNLOCK(_pthread_list_lock);

                        *thread = t;

#if WQ_TRACE
                __kdebug_trace(0x9000014, t, 0, 0, 1, 0);
#endif
                        return (0);

                } else {
                        /* kernel allocation */
#if WQ_TRACE
                __kdebug_trace(0x9000018, flags, 0, 0, 0, 0);
#endif
                        if ((t = __bsdthread_create(start_routine, arg, attrs->stacksize, NULL, flags)) == -1)
                                return (EAGAIN);
                        /* Now set it up to execute */
                        LOCK(_pthread_list_lock);
                        t->parentcheck = 1;
                        if ((t->childexit != 0) && ((t->detached & PTHREAD_CREATE_DETACHED) == PTHREAD_CREATE_DETACHED)) {
                                /* detached child exited, mop up */
                                UNLOCK(_pthread_list_lock);
#if WQ_TRACE
                        __kdebug_trace(0x9000008, t, pthreadsize, 0, 2, 0);
#endif
                                vm_deallocate(self, t, pthreadsize);
                        } else if (t->childrun == 0) {
                                TAILQ_INSERT_TAIL(&__pthread_head, t, plist);
                                _pthread_count++;
#if WQ_TRACE
                                __kdebug_trace(0x900000c, t, 0, 0, 2, 0);
#endif
                                UNLOCK(_pthread_list_lock);
                        } else 
                                UNLOCK(_pthread_list_lock);

                        *thread = t;

#if WQ_TRACE
                        __kdebug_trace(0x9000014, t, 0, 0, 2, 0);
#endif
                        return(0);
                }
        }
}

static int       
_pthread_create_suspended(pthread_t *thread, 
               const pthread_attr_t *attr,
               void *(*start_routine)(void *), 
               void *arg,
           int suspended)
{
        pthread_attr_t *attrs;
        void *stack;
        int res;
        pthread_t t;
        kern_return_t kern_res;
        mach_port_t kernel_thread = MACH_PORT_NULL;
        int needresume;

        if ((attrs = (pthread_attr_t *)attr) == (pthread_attr_t *)NULL)
        {                       /* Set up default paramters */
                attrs = &_pthread_attr_default;
        } else if (attrs->sig != _PTHREAD_ATTR_SIG) {
            return EINVAL;
        }
        res = 0;

        /* In default policy (ie SCHED_OTHER) only sched_priority is used. Check for
         * any change in priority or policy is needed here.
         */
        if (((attrs->policy != _PTHREAD_DEFAULT_POLICY)  || 
                (attrs->param.sched_priority != default_priority)) && (suspended == 0)) {
                needresume = 1; 
                suspended = 1;  
        } else 
                needresume = 0;

        do
        {
                /* Allocate a stack for the thread */
                if ((res = _pthread_allocate_stack(attrs, &stack)) != 0) {
                    break;
                }
                t = (pthread_t)malloc(sizeof(struct _pthread));
                *thread = t;
                if (suspended) {
                        /* Create the Mach thread for this thread */
                        PTHREAD_MACH_CALL(thread_create(mach_task_self(), &kernel_thread), kern_res);
                        if (kern_res != KERN_SUCCESS)
                        {
                                printf("Can't create thread: %d\n", kern_res);
                                res = EINVAL; /* Need better error here? */
                                break;
                        }
                }
                if ((res = _pthread_create(t, attrs, stack, kernel_thread)) != 0)
                {
                        break;
                }
                set_malloc_singlethreaded(0);
                __is_threaded = 1;

                /* Send it on it's way */
                t->arg = arg;
                t->fun = start_routine;
                /* Now set it up to execute */
                LOCK(_pthread_list_lock);
                TAILQ_INSERT_TAIL(&__pthread_head, t, plist);
#if WQ_TRACE
                __kdebug_trace(0x900000c, t, 0, 0, 5, 0);
#endif
                _pthread_count++;
                UNLOCK(_pthread_list_lock);
                _pthread_setup(t, _pthread_body, stack, suspended, needresume);
        } while (0);
        return (res);
}

int
pthread_create(pthread_t *thread,
           const pthread_attr_t *attr,
           void *(*start_routine)(void *),
           void *arg)
{
    return _new_pthread_create_suspended(thread, attr, start_routine, arg, 0);
}

int
pthread_create_suspended_np(pthread_t *thread,
           const pthread_attr_t *attr,
           void *(*start_routine)(void *),
           void *arg)
{
    return _pthread_create_suspended(thread, attr, start_routine, arg, 1);
}

/*
 * Make a thread 'undetached' - no longer 'joinable' with other threads.
 */
int       
pthread_detach(pthread_t thread)
{
        int newstyle = 0;
        int ret;

        if ((ret = _pthread_lookup_thread(thread, NULL, 1)) != 0)
                return (ret); /* Not a valid thread */
                
        LOCK(thread->lock);
        newstyle = thread->newstyle;
        if (thread->detached & PTHREAD_CREATE_JOINABLE)
        {
                if (thread->detached & _PTHREAD_EXITED) {
                        UNLOCK(thread->lock);
                        pthread_join(thread, NULL);
                        return 0;
                } else {
                        if (newstyle == 0) {
                                semaphore_t death = thread->death;

                                thread->detached &= ~PTHREAD_CREATE_JOINABLE;
                                thread->detached |= PTHREAD_CREATE_DETACHED;
                                UNLOCK(thread->lock);
                                if (death)
                                        (void) semaphore_signal(death);
                        } else {
                                mach_port_t joinport = thread->joiner_notify;
        
                                thread->detached &= ~PTHREAD_CREATE_JOINABLE;
                                thread->detached |= PTHREAD_CREATE_DETACHED;
                                
                                UNLOCK(thread->lock);
                                if (joinport) {
                                        semaphore_signal(joinport);
                                }
                        }
                        return(0);
                }
        } else {
                UNLOCK(thread->lock);
                return (EINVAL);
        }
}


/* 
 * pthread_kill call to system call
 */

extern int __pthread_kill(mach_port_t, int);

int   
pthread_kill (
        pthread_t th,
        int sig)
{
        int error = 0;
        mach_port_t kport = MACH_PORT_NULL;
        
        if ((sig < 0) || (sig > NSIG))
                return(EINVAL);

        if (_pthread_lookup_thread(th, &kport, 0) != 0)
                return (ESRCH); /* Not a valid thread */

        error = __pthread_kill(kport, sig);

        if (error == -1)
                error = errno;
        return(error);
}

/* Announce that there are pthread resources ready to be reclaimed in a */
/* subsequent pthread_exit or reaped by pthread_join. In either case, the Mach */
/* thread underneath is terminated right away. */
static
void _pthread_become_available(pthread_t thread, mach_port_t kernel_thread) {
        pthread_reap_msg_t msg;
        kern_return_t ret;

        msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_MAKE_SEND,
                                              MACH_MSG_TYPE_MOVE_SEND);
        msg.header.msgh_size = sizeof msg - sizeof msg.trailer;
        msg.header.msgh_remote_port = thread_recycle_port;
        msg.header.msgh_local_port = kernel_thread; 
        msg.header.msgh_id = 0x44454144; /* 'DEAD' */
        msg.thread = thread;
        ret = mach_msg_send(&msg.header);
        assert(ret == MACH_MSG_SUCCESS);
}

/* Reap the resources for available threads */
__private_extern__
int _pthread_reap_thread(pthread_t th, mach_port_t kernel_thread, void **value_ptr, int conforming) {
        mach_port_type_t ptype;
        kern_return_t ret;
        task_t self;

        self = mach_task_self();
        if (kernel_thread != MACH_PORT_DEAD) {
                ret = mach_port_type(self, kernel_thread, &ptype);
                if (ret == KERN_SUCCESS && ptype != MACH_PORT_TYPE_DEAD_NAME) {
                        /* not quite dead yet... */
                        return EAGAIN;
                }
                ret = mach_port_deallocate(self, kernel_thread);
                if (ret != KERN_SUCCESS) {
                        fprintf(stderr,
                                  "mach_port_deallocate(kernel_thread) failed: %s\n",
                                  mach_error_string(ret));
                }
        }

        if (th->reply_port != MACH_PORT_NULL) {
                ret = mach_port_mod_refs(self, th->reply_port,
                                                 MACH_PORT_RIGHT_RECEIVE, -1);
                if (ret != KERN_SUCCESS) {
                        fprintf(stderr,
                                  "mach_port_mod_refs(reply_port) failed: %s\n",
                                  mach_error_string(ret));
                }
        }

        if (th->freeStackOnExit) {
                vm_address_t addr = (vm_address_t)th->stackaddr;
                vm_size_t size;

                size = (vm_size_t)th->stacksize + th->guardsize;
                
                addr -= size;
                ret = vm_deallocate(self, addr, size);
                if (ret != KERN_SUCCESS) {
                  fprintf(stderr,
                                    "vm_deallocate(stack) failed: %s\n",
                                    mach_error_string(ret));
                }
        }


        if (value_ptr) 
                *value_ptr = th->exit_value;
        if (conforming) {
                if ((th->cancel_state & (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING)) ==
            (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING)) 
                        *value_ptr = PTHREAD_CANCELED;
                th->sig = _PTHREAD_NO_SIG;
        }


        if (th != &_thread)
                free(th);

        return 0;
}

static
void _pthread_reap_threads(void)
{
        pthread_reap_msg_t msg;
        kern_return_t ret;

        ret = mach_msg(&msg.header, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0,
                        sizeof msg, thread_recycle_port, 
                        MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
        while (ret == MACH_MSG_SUCCESS) {
                mach_port_t kernel_thread = msg.header.msgh_remote_port;
                pthread_t thread = msg.thread;

                if (_pthread_reap_thread(thread, kernel_thread, (void **)0, 0) == EAGAIN)
                {
                        /* not dead yet, put it back for someone else to reap, stop here */
                        _pthread_become_available(thread, kernel_thread);
                        return;
                }
                ret = mach_msg(&msg.header, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0,
                                sizeof msg, thread_recycle_port, 
                                MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
        }
}

/* For compatibility... */

pthread_t
_pthread_self() {
        return pthread_self();
}

/*
 * Terminate a thread.
 */
int __disable_threadsignal(int);

static void 
_pthread_exit(pthread_t self, void *value_ptr)
{
        struct __darwin_pthread_handler_rec *handler;
        kern_return_t kern_res;
        int thread_count;
        int newstyle = self->newstyle;

        /* Make this thread not to receive any signals */
        __disable_threadsignal(1);

#if WQ_TRACE
        __kdebug_trace(0x900001c, self, newstyle, 0, 0, 0);
#endif

        /* set cancel state to disable and type to deferred */
        _pthread_setcancelstate_exit(self, value_ptr, __unix_conforming);

        while ((handler = self->__cleanup_stack) != 0)
        {
                (handler->__routine)(handler->__arg);
                self->__cleanup_stack = handler->__next;
        }
        _pthread_tsd_cleanup(self);

        if (newstyle == 0) {
                _pthread_reap_threads();

                LOCK(self->lock);
                self->detached |= _PTHREAD_EXITED;

                if (self->detached & PTHREAD_CREATE_JOINABLE) {
                        mach_port_t death = self->death;
                        self->exit_value = value_ptr;
                        UNLOCK(self->lock);
                        /* the joiner will need a kernel thread reference, leave ours for it */
                        if (death) {
                                PTHREAD_MACH_CALL(semaphore_signal(death), kern_res);
                                if (kern_res != KERN_SUCCESS)
                                        fprintf(stderr,
                                                "semaphore_signal(death) failed: %s\n",
                                                mach_error_string(kern_res));
                        }
                        LOCK(_pthread_list_lock);
                        thread_count = --_pthread_count;
                        UNLOCK(_pthread_list_lock);
                } else {
                        UNLOCK(self->lock);
                        LOCK(_pthread_list_lock);
                        TAILQ_REMOVE(&__pthread_head, self, plist);
#if WQ_TRACE
                        __kdebug_trace(0x9000010, self, 0, 0, 5, 0);
#endif
                        thread_count = --_pthread_count;
                        UNLOCK(_pthread_list_lock);
                        /* with no joiner, we let become available consume our cached ref */
                        _pthread_become_available(self, self->kernel_thread);
                }

                if (thread_count <= 0)
                        exit(0);

                /* Use a new reference to terminate ourselves. Should never return. */
                PTHREAD_MACH_CALL(thread_terminate(mach_thread_self()), kern_res);
                fprintf(stderr, "thread_terminate(mach_thread_self()) failed: %s\n",
                                mach_error_string(kern_res));
        } else {
                semaphore_t joinsem = SEMAPHORE_NULL;

                if ((self->joiner_notify == NULL) && (self->detached & PTHREAD_CREATE_JOINABLE))
                        joinsem = new_sem_from_pool();
                LOCK(self->lock);
                self->detached |= _PTHREAD_EXITED;

                self->exit_value = value_ptr;
                if (self->detached & PTHREAD_CREATE_JOINABLE) {
                        if (self->joiner_notify == NULL) {
                                self->joiner_notify = joinsem;
                                joinsem = SEMAPHORE_NULL;
                        }
                        UNLOCK(self->lock);
                        if (joinsem != SEMAPHORE_NULL)
                                restore_sem_to_pool(joinsem);
                        _pthread_free_pthread_onstack(self, 0, 1);
                } else {
                        UNLOCK(self->lock);
                        /* with no joiner, we let become available consume our cached ref */
                        if (joinsem != SEMAPHORE_NULL)
                                restore_sem_to_pool(joinsem);
                        _pthread_free_pthread_onstack(self, 1, 1);
                }
        }
        abort();
}

void
pthread_exit(void *value_ptr)
{
        pthread_t self = pthread_self();
        if (self->wqthread != 0)
                workqueue_exit(self, self->cur_workq, self->cur_workitem);
        else
                _pthread_exit(self, value_ptr);
}

/*
 * Get the scheduling policy and scheduling paramters for a thread.
 */
int       
pthread_getschedparam(pthread_t thread, 
                      int *policy,
                      struct sched_param *param)
{
        int ret;

        if (thread == NULL)
                return(ESRCH);
        
        LOCK(_pthread_list_lock);

        if ((ret = _pthread_find_thread(thread)) != 0) {
                UNLOCK(_pthread_list_lock);
                return(ret);
        }
        if (policy != 0)
                *policy = thread->policy;
        if (param != 0)
                *param = thread->param;
        UNLOCK(_pthread_list_lock);

        return(0);
}

/*
 * Set the scheduling policy and scheduling paramters for a thread.
 */
int       
pthread_setschedparam(pthread_t thread, 
                      int policy,
                      const struct sched_param *param)
{
        policy_base_data_t bases;
        policy_base_t base;
        mach_msg_type_number_t count;
        kern_return_t ret;

        switch (policy)
        {
                case SCHED_OTHER:
                        bases.ts.base_priority = param->sched_priority;
                        base = (policy_base_t)&bases.ts;
                        count = POLICY_TIMESHARE_BASE_COUNT;
                        break;
                case SCHED_FIFO:
                        bases.fifo.base_priority = param->sched_priority;
                        base = (policy_base_t)&bases.fifo;
                        count = POLICY_FIFO_BASE_COUNT;
                        break;
                case SCHED_RR:
                        bases.rr.base_priority = param->sched_priority;
                        /* quantum isn't public yet */
                        bases.rr.quantum = param->quantum;
                        base = (policy_base_t)&bases.rr;
                        count = POLICY_RR_BASE_COUNT;
                        break;
                default:
                        return (EINVAL);
        }
        ret = thread_policy(pthread_mach_thread_np(thread), policy, base, count, TRUE);
        if (ret != KERN_SUCCESS)
                        return (EINVAL);
        thread->policy = policy;
        thread->param = *param;
        return (0);
}

/*
 * Get the minimum priority for the given policy
 */
int
sched_get_priority_min(int policy)
{
    return default_priority - 16;
}

/*
 * Get the maximum priority for the given policy
 */
int
sched_get_priority_max(int policy)
{
    return default_priority + 16;
}

/*
 * Determine if two thread identifiers represent the same thread.
 */
int       
pthread_equal(pthread_t t1, 
              pthread_t t2)
{
        return (t1 == t2);
}

__private_extern__ void
_pthread_set_self(pthread_t p)
{
        extern void __pthread_set_self(pthread_t);
        if (p == 0) {
                bzero(&_thread, sizeof(struct _pthread));
                p = &_thread;
        }
        p->tsd[0] = p;
        __pthread_set_self(p);
}

void 
cthread_set_self(void *cself)
{
    pthread_t self = pthread_self();
    if ((self == (pthread_t)NULL) || (self->sig != _PTHREAD_SIG)) {
        _pthread_set_self(cself);
        return;
    }
    self->cthread_self = cself;
}

void *
ur_cthread_self(void) {
    pthread_t self = pthread_self();
    if ((self == (pthread_t)NULL) || (self->sig != _PTHREAD_SIG)) {
        return (void *)self;
    }
    return self->cthread_self;
}

/*
 * cancellation handler for pthread once as the init routine can have a
 * cancellation point. In that case we need to restore the spin unlock 
 */
void
__pthread_once_cancel_handler(pthread_once_t *once_control)
{
                _spin_unlock(&once_control->lock);
}


/*
 * Execute a function exactly one time in a thread-safe fashion.
 */
int       
pthread_once(pthread_once_t *once_control, 
             void (*init_routine)(void))
{
        _spin_lock(&once_control->lock);
        if (once_control->sig == _PTHREAD_ONCE_SIG_init)
        {
                pthread_cleanup_push(__pthread_once_cancel_handler, once_control);
                (*init_routine)();
                pthread_cleanup_pop(0);
                once_control->sig = _PTHREAD_ONCE_SIG;
        }
        _spin_unlock(&once_control->lock);
        return (0);  /* Spec defines no possible errors! */
}

/*
 * Insert a cancellation point in a thread.
 */
__private_extern__ void
_pthread_testcancel(pthread_t thread, int isconforming)
{
        LOCK(thread->lock);
        if ((thread->cancel_state & (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING)) == 
            (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING))
        {
                UNLOCK(thread->lock);
                if (isconforming)
                        pthread_exit(PTHREAD_CANCELED);
                else
                        pthread_exit(0);
        }
        UNLOCK(thread->lock);
}



int
pthread_getconcurrency(void)
{
        return(pthread_concurrency);
}

int
pthread_setconcurrency(int new_level)
{
        if (new_level < 0)
                return EINVAL;
        pthread_concurrency = new_level;
        return(0);
}

/*
 * Perform package initialization - called automatically when application starts
 */

__private_extern__ int
pthread_init(void)
{
        pthread_attr_t *attrs;
        pthread_t thread;
        kern_return_t kr;
        host_priority_info_data_t priority_info;
        host_info_t info;
        host_flavor_t flavor;
        host_t host;
        mach_msg_type_number_t count;
        int mib[2];
        size_t len;
        void *stackaddr;

        pthreadsize = round_page(sizeof (struct _pthread));
        count = HOST_PRIORITY_INFO_COUNT;
        info = (host_info_t)&priority_info;
        flavor = HOST_PRIORITY_INFO;
        host = mach_host_self();
        kr = host_info(host, flavor, info, &count);
        if (kr != KERN_SUCCESS)
                printf("host_info failed (%d); probably need privilege.\n", kr);
        else {
                default_priority = priority_info.user_priority;
                min_priority = priority_info.minimum_priority;
                max_priority = priority_info.maximum_priority;
        }
        attrs = &_pthread_attr_default;
        pthread_attr_init(attrs);

        TAILQ_INIT(&__pthread_head);
        LOCK_INIT(_pthread_list_lock);
        thread = &_thread;
        TAILQ_INSERT_HEAD(&__pthread_head, thread, plist);
        _pthread_set_self(thread);

        /* In case of dyld reset the tsd keys from 1 - 10 */
        _pthread_keys_init();

        mib[0] = CTL_KERN;
        mib[1] = KERN_USRSTACK;
        len = sizeof (stackaddr);
        if (sysctl (mib, 2, &stackaddr, &len, NULL, 0) != 0)
                stackaddr = (void *)USRSTACK;
        _pthread_create(thread, attrs, stackaddr, mach_thread_self());
        thread->detached = PTHREAD_CREATE_JOINABLE|_PTHREAD_CREATE_PARENT;

        _init_cpu_capabilities();
        if (_NumCPUs() > 1)
                _spin_tries = MP_SPIN_TRIES;

        mach_port_deallocate(mach_task_self(), host);
    
#if defined(__ppc__)
        IF_ROSETTA() {
                __oldstyle = 1;
        }
#endif
#if defined(__arm__)
        __oldstyle = 1;
#endif

#if defined(_OBJC_PAGE_BASE_ADDRESS)
{
        vm_address_t objcRTPage = (vm_address_t)_OBJC_PAGE_BASE_ADDRESS;
        kr = vm_map(mach_task_self(),
                 &objcRTPage, vm_page_size * 4, vm_page_size - 1,
                 VM_FLAGS_FIXED | VM_MAKE_TAG(0), // Which tag to use?
                 MACH_PORT_NULL,
                 (vm_address_t)0, FALSE,
                 (vm_prot_t)0, VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE,
                 VM_INHERIT_DEFAULT);
                /* We ignore the return result here. The ObjC runtime will just have to deal. */
}
#endif

        mig_init(1);            /* enable multi-threaded mig interfaces */
        if (__oldstyle == 0) {
#if defined(__i386__) || defined(__x86_64__)
                __bsdthread_register(thread_start, start_wqthread, round_page(sizeof(struct _pthread)));
#else
                __bsdthread_register(_pthread_start, _pthread_wqthread, round_page(sizeof(struct _pthread)));
#endif
        }
        return 0;
}

int sched_yield(void)
{
    swtch_pri(0);
    return 0;
}

/* This used to be the "magic" that gets the initialization routine called when the application starts */
static int _do_nothing(void) { return 0; }
int (*_cthread_init_routine)(void) = _do_nothing;

/* Get a semaphore from the pool, growing it if necessary */

__private_extern__ semaphore_t new_sem_from_pool(void) {
        kern_return_t res;
        semaphore_t sem;
        int i;
        
        LOCK(sem_pool_lock);
        if (sem_pool_current == sem_pool_count) {
                sem_pool_count += 16;
                sem_pool = realloc(sem_pool, sem_pool_count * sizeof(semaphore_t));
                for (i = sem_pool_current; i < sem_pool_count; i++) {
                        PTHREAD_MACH_CALL(semaphore_create(mach_task_self(), &sem_pool[i], SYNC_POLICY_FIFO, 0), res);
                }
        }
        sem = sem_pool[sem_pool_current++];
        UNLOCK(sem_pool_lock);
        return sem;
}

/* Put a semaphore back into the pool */
__private_extern__ void restore_sem_to_pool(semaphore_t sem) {
        LOCK(sem_pool_lock);
        sem_pool[--sem_pool_current] = sem;
        UNLOCK(sem_pool_lock);
}

static void sem_pool_reset(void) {
        LOCK(sem_pool_lock);
        sem_pool_count = 0;
        sem_pool_current = 0;
        sem_pool = NULL; 
        UNLOCK(sem_pool_lock);
}

__private_extern__ void _pthread_fork_child(pthread_t p) {
        /* Just in case somebody had it locked... */
        UNLOCK(sem_pool_lock);
        sem_pool_reset();
        /* No need to hold the pthread_list_lock as no one other than this 
         * thread is present at this time
         */
        TAILQ_INIT(&__pthread_head);
        LOCK_INIT(_pthread_list_lock);
        TAILQ_INSERT_HEAD(&__pthread_head, p, plist);
        _pthread_count = 1;
}

/*
 * Query/update the cancelability 'state' of a thread
 */
int
_pthread_setcancelstate_internal(int state, int *oldstate, int conforming)
{
        pthread_t self = pthread_self();


        switch (state) {
                case PTHREAD_CANCEL_ENABLE:
                if (conforming)
                        __pthread_canceled(1);
                        break;
                case PTHREAD_CANCEL_DISABLE:
                if (conforming)
                        __pthread_canceled(2);
                        break;
                default:
                        return EINVAL;
        }

        self = pthread_self();
        LOCK(self->lock);
        if (oldstate)
                *oldstate = self->cancel_state & _PTHREAD_CANCEL_STATE_MASK;
        self->cancel_state &= ~_PTHREAD_CANCEL_STATE_MASK;
        self->cancel_state |= state;
        UNLOCK(self->lock);
        if (!conforming)
                _pthread_testcancel(self, 0);  /* See if we need to 'die' now... */
        return (0);
}

/* When a thread exits set the cancellation state to DISABLE and DEFERRED */
static void
_pthread_setcancelstate_exit(pthread_t self, void * value_ptr, int conforming)
{
        LOCK(self->lock);
        self->cancel_state &= ~(_PTHREAD_CANCEL_STATE_MASK | _PTHREAD_CANCEL_TYPE_MASK);
        self->cancel_state |= (PTHREAD_CANCEL_DISABLE | PTHREAD_CANCEL_DEFERRED);
        if ((value_ptr == PTHREAD_CANCELED)) {
// 4597450: begin
                self->detached |= _PTHREAD_WASCANCEL;
// 4597450: end
        }
        UNLOCK(self->lock);
}

int
_pthread_join_cleanup(pthread_t thread, void ** value_ptr, int conforming)
{
        kern_return_t res;
        int detached = 0, ret;

#if WQ_TRACE
        __kdebug_trace(0x9000028, thread, 0, 0, 1, 0);
#endif
        /* The scenario where the joiner was waiting for the thread and
         * the pthread detach happened on that thread. Then the semaphore
         * will trigger but by the time joiner runs, the target thread could be
         * freed. So we need to make sure that the thread is still in the list 
         * and is joinable  before we continue with the join.
         */
        LOCK(_pthread_list_lock);
        if ((ret = _pthread_find_thread(thread)) != 0) {
                UNLOCK(_pthread_list_lock);
                /* returns ESRCH */
                return(ret);
        }
        if ((thread->detached & PTHREAD_CREATE_JOINABLE) == 0) {
                /* the thread might be a detached thread */
                UNLOCK(_pthread_list_lock);
                return(ESRCH);

        }
        /* It is still a joinable thread and needs to be reaped */
        TAILQ_REMOVE(&__pthread_head, thread, plist);
#if WQ_TRACE
        __kdebug_trace(0x9000010, thread, 0, 0, 3, 0);
#endif
        UNLOCK(_pthread_list_lock);

        if (value_ptr)
                *value_ptr = thread->exit_value;
        if (conforming) {
                if ((thread->cancel_state & (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING)) ==
                        (PTHREAD_CANCEL_ENABLE|_PTHREAD_CANCEL_PENDING)) {
                        *value_ptr = PTHREAD_CANCELED;
                }
        }
        if (thread->reply_port != MACH_PORT_NULL) {
                res = mach_port_mod_refs(mach_task_self(), thread->reply_port, MACH_PORT_RIGHT_RECEIVE, -1);
                if (res != KERN_SUCCESS) 
                        fprintf(stderr,"mach_port_mod_refs(reply_port) failed: %s\n",mach_error_string(res));
                thread->reply_port = MACH_PORT_NULL;
        }
        if (thread->freeStackOnExit) {
                thread->sig = _PTHREAD_NO_SIG;
#if WQ_TRACE
        __kdebug_trace(0x9000028, thread, 0, 0, 2, 0);
#endif
                vm_deallocate(mach_task_self(), thread, pthreadsize);
        } else {
                thread->sig = _PTHREAD_NO_SIG;
#if WQ_TRACE
        __kdebug_trace(0x9000028, thread, 0, 0, 3, 0);
#endif
                free(thread);
        }
        return(0);
}

/* ALWAYS called with list lock and return with list lock */
int
_pthread_find_thread(pthread_t thread)
{
        pthread_t p;

loop:
        TAILQ_FOREACH(p, &__pthread_head, plist) {
                if (p == thread) {
                        if (thread->kernel_thread == MACH_PORT_NULL) {
                                UNLOCK(_pthread_list_lock);
                                sched_yield();
                                LOCK(_pthread_list_lock);
                                goto loop;
                        } 
                        return(0);
                }
        }
        return(ESRCH);
}

int
_pthread_lookup_thread(pthread_t thread, mach_port_t * portp, int only_joinable)
{
        mach_port_t kport;
        int ret = 0;

        if (thread == NULL)
                return(ESRCH);
        
        LOCK(_pthread_list_lock);

        if ((ret = _pthread_find_thread(thread)) != 0) {
                UNLOCK(_pthread_list_lock);
                return(ret);
        }
        if ((only_joinable != 0) && ((thread->detached & PTHREAD_CREATE_DETACHED) != 0)) {
                UNLOCK(_pthread_list_lock);
                return(EINVAL);
        } 
        kport = thread->kernel_thread;
        UNLOCK(_pthread_list_lock);
        if (portp != NULL)
                *portp = kport;
        return(0);
}

/* XXXXXXXXXXXXX Pthread Workqueue Attributes XXXXXXXXXXXXXXXXXX */
int 
pthread_workqueue_attr_init_np(pthread_workqueue_attr_t * attrp)
{
        attrp->stacksize = DEFAULT_STACK_SIZE;
        attrp->istimeshare = 1;
        attrp->importance = 0;
        attrp->affinity = 0;
        attrp->queueprio = WORK_QUEUE_NORMALIZER;
        attrp->sig = PTHEAD_WRKQUEUE_ATTR_SIG;
        return(0);
}

int 
pthread_workqueue_attr_destroy_np(pthread_workqueue_attr_t * attr)
{
        if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG)
        {
                return (0);
        } else
        {
                return (EINVAL); /* Not an attribute structure! */
        }
}

#ifdef NOTYET /* [ */
int 
pthread_workqueue_attr_getstacksize_np(const pthread_workqueue_attr_t * attr, size_t * stacksizep)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        *stacksizep = attr->stacksize;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_setstacksize_np(pthread_workqueue_attr_t * attr, size_t stacksize)
{
    if ((attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) && ((stacksize % vm_page_size) == 0) && (stacksize >= PTHREAD_STACK_MIN)) {
        attr->stacksize = stacksize;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}


int 
pthread_workqueue_attr_getthreadtimeshare_np(const pthread_workqueue_attr_t * attr, int * istimesahrep)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        *istimesahrep = attr->istimeshare;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_settthreadtimeshare_np(pthread_workqueue_attr_t * attr, int istimeshare)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        if (istimeshare != 0)
                attr->istimeshare = istimeshare;
        else
                attr->istimeshare = 0;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_getthreadimportance_np(const pthread_workqueue_attr_t * attr, int * importancep)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        *importancep = attr->importance;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_settthreadimportance_np(pthread_workqueue_attr_t * attr, int importance)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG){
        attr->importance = importance;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_getthreadaffinity_np(const pthread_workqueue_attr_t * attr, int * affinityp)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        *affinityp = attr->affinity;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_settthreadaffinity_np(pthread_workqueue_attr_t * attr, int affinity)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG){
        attr->affinity = affinity;
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

#endif /* NOTYET  ] */

int 
pthread_workqueue_attr_getqueuepriority_np(const pthread_workqueue_attr_t * attr, int * qpriop)
{
    if (attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) {
        *qpriop = (attr->queueprio - WORK_QUEUE_NORMALIZER);
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

int 
pthread_workqueue_attr_setqueuepriority_np(pthread_workqueue_attr_t * attr, int qprio)
{
        /* only -2 to +2 is valid */
    if ((attr->sig == PTHEAD_WRKQUEUE_ATTR_SIG) && (qprio <= 2) && (qprio >= -2)) {
        attr->queueprio = (qprio + WORK_QUEUE_NORMALIZER);
        return (0);
    } else {
        return (EINVAL); /* Not an attribute structure! */
    }
}

/* XXXXXXXXXXXXX Pthread Workqueue support routines XXXXXXXXXXXXXXXXXX */

static void
workqueue_list_lock()
{
        OSSpinLockLock(&__workqueue_list_lock);
}

static void
workqueue_list_unlock()
{
        OSSpinLockUnlock(&__workqueue_list_lock);
}

int
pthread_workqueue_init_np()
{
        int ret;

        workqueue_list_lock();
        ret =_pthread_work_internal_init();
        workqueue_list_unlock();

        return(ret);
}

static int
_pthread_work_internal_init(void)
{
        int i, error;
        pthread_workqueue_head_t headp;
        pthread_workitem_t witemp;
        pthread_workqueue_t wq;

        if (kernel_workq_setup == 0) {
#if defined(__i386__) || defined(__x86_64__)
                __bsdthread_register(thread_start, start_wqthread, round_page(sizeof(struct _pthread)));
#else
                __bsdthread_register(_pthread_start, _pthread_wqthread, round_page(sizeof(struct _pthread)));
#endif

                _pthread_wq_attr_default.stacksize = DEFAULT_STACK_SIZE;
                _pthread_wq_attr_default.istimeshare = 1;
                _pthread_wq_attr_default.importance = 0;
                _pthread_wq_attr_default.affinity = 0;
                _pthread_wq_attr_default.queueprio = WORK_QUEUE_NORMALIZER;
                _pthread_wq_attr_default.sig = PTHEAD_WRKQUEUE_ATTR_SIG;

                for( i = 0; i< WQ_NUM_PRIO_QS; i++) {
                        headp = __pthread_wq_head_tbl[i];
                        TAILQ_INIT(&headp->wqhead);
                        headp->next_workq = 0;
                }

                /* create work item and workqueue pools */
                witemp = (struct _pthread_workitem *)malloc(sizeof(struct _pthread_workitem) * WORKITEM_POOL_SIZE);
                bzero(witemp, (sizeof(struct _pthread_workitem) * WORKITEM_POOL_SIZE));
                for (i = 0; i < WORKITEM_POOL_SIZE; i++) {
                        TAILQ_INSERT_TAIL(&__pthread_workitem_pool_head, &witemp[i], item_entry);
                }
                wq = (struct _pthread_workqueue *)malloc(sizeof(struct _pthread_workqueue) * WORKQUEUE_POOL_SIZE);
                bzero(wq, (sizeof(struct _pthread_workqueue) * WORKQUEUE_POOL_SIZE));
                for (i = 0; i < WORKQUEUE_POOL_SIZE; i++) {
                        TAILQ_INSERT_TAIL(&__pthread_workqueue_pool_head, &wq[i], wq_list);
                }

                if (error = __workq_open()) {
                        TAILQ_INIT(&__pthread_workitem_pool_head);
                        TAILQ_INIT(&__pthread_workqueue_pool_head);
                        free(witemp);
                        free(wq);
                        return(ENOMEM);
                }
                kernel_workq_setup = 1;
        }
        return(0);
}


/* This routine is called with list lock held */
static pthread_workitem_t
alloc_workitem(void)
{
        pthread_workitem_t witem;

        if (TAILQ_EMPTY(&__pthread_workitem_pool_head)) {
                workqueue_list_unlock();
                witem = malloc(sizeof(struct _pthread_workitem));
                workqueue_list_lock();
        } else {
                witem = TAILQ_FIRST(&__pthread_workitem_pool_head);
                TAILQ_REMOVE(&__pthread_workitem_pool_head, witem, item_entry);
        }
        return(witem);
}

/* This routine is called with list lock held */
static void
free_workitem(pthread_workitem_t witem) 
{
        TAILQ_INSERT_TAIL(&__pthread_workitem_pool_head, witem, item_entry);
}

/* This routine is called with list lock held */
static pthread_workqueue_t
alloc_workqueue(void)
{
        pthread_workqueue_t wq;

        if (TAILQ_EMPTY(&__pthread_workqueue_pool_head)) {
                workqueue_list_unlock();
                wq = malloc(sizeof(struct _pthread_workqueue));
                workqueue_list_lock();
        } else {
                wq = TAILQ_FIRST(&__pthread_workqueue_pool_head);
                TAILQ_REMOVE(&__pthread_workqueue_pool_head, wq, wq_list);
        }
        user_workq_count++;
        return(wq);
}

/* This routine is called with list lock held */
static void
free_workqueue(pthread_workqueue_t wq) 
{
        user_workq_count--;
        TAILQ_INSERT_TAIL(&__pthread_workqueue_pool_head, wq, wq_list);
}

static void
_pthread_workq_init(pthread_workqueue_t wq, const pthread_workqueue_attr_t * attr)
{
        bzero(wq, sizeof(struct _pthread_workqueue));
        if (attr != NULL) {
                wq->stacksize = attr->stacksize;
                wq->istimeshare = attr->istimeshare;
                wq->importance = attr->importance;
                wq->affinity = attr->affinity;
                wq->queueprio = attr->queueprio;
         } else {
                wq->stacksize = DEFAULT_STACK_SIZE;
                wq->istimeshare = 1;
                wq->importance = 0;
                wq->affinity = 0;
                wq->queueprio = WORK_QUEUE_NORMALIZER;
        }
        LOCK_INIT(wq->lock);
        wq->flags = 0;
        TAILQ_INIT(&wq->item_listhead);
        TAILQ_INIT(&wq->item_kernhead);
        wq->wq_list.tqe_next = 0;
        wq->wq_list.tqe_prev = 0;
        wq->sig = PTHEAD_WRKQUEUE_SIG;
        wq->headp = __pthread_wq_head_tbl[wq->queueprio];
}

int 
valid_workq(pthread_workqueue_t workq)
{
        if (workq->sig == PTHEAD_WRKQUEUE_SIG) 
                return(1);
        else
                return(0);
}


/* called with list lock */
static void
pick_nextworkqueue_droplock()
{
        int i, curwqprio, val, found;
        pthread_workqueue_head_t headp;
        pthread_workqueue_t workq;
        pthread_workqueue_t nworkq = NULL;

loop:
        while (kernel_workq_count < KERNEL_WORKQ_ELEM_MAX) {
                found = 0;
                for (i = 0; i < WQ_NUM_PRIO_QS; i++)  {
                        wqreadyprio = i;        /* because there is nothing else higher to run */
                        headp = __pthread_wq_head_tbl[i];

                        if (TAILQ_EMPTY(&headp->wqhead))
                                continue;
                        workq = headp->next_workq;
                        if (workq == NULL)
                                workq = TAILQ_FIRST(&headp->wqhead);
                        curwqprio = workq->queueprio;
                        nworkq = workq; /* starting pt */
                        while (kernel_workq_count < KERNEL_WORKQ_ELEM_MAX) {
                                headp->next_workq = TAILQ_NEXT(workq, wq_list);
                                if (headp->next_workq == NULL)
                                        headp->next_workq = TAILQ_FIRST(&headp->wqhead);
                                val = post_nextworkitem(workq);

                                if (val != 0) {
                                        /* things could have changed so reasses */
                                        /* If kernel queue is full , skip */
                                        if (kernel_workq_count >= KERNEL_WORKQ_ELEM_MAX)
                                                break;
                                        /* If anything with higher prio arrived, then reevaluate */
                                        if (wqreadyprio < curwqprio)
                                                goto loop;      /* we need re evaluate again */
                                        /* we can post some more work items */
                                        found = 1;
                                }

                                /* cannot use workq here as it could be freed */
                                if (TAILQ_EMPTY(&headp->wqhead))
                                        break;
                                /* if we found nothing to run and only one workqueue in the list, skip */
                                if ((val == 0) && (workq == headp->next_workq))
                                        break;
                                workq = headp->next_workq;
                                if (workq == NULL)
                                        workq = TAILQ_FIRST(&headp->wqhead);
                                if (val != 0)
                                        nworkq = workq;
                                /* if we found nothing to run and back to workq where we started */
                                if ((val == 0) && (workq == nworkq))
                                        break;
                        }
                        if (kernel_workq_count >= KERNEL_WORKQ_ELEM_MAX)
                                break;
                }
                /* nothing found to run?  */
                if (found == 0)
                        break;
        }
        workqueue_list_unlock();
}

static int
post_nextworkitem(pthread_workqueue_t workq)
{
        int error;
        pthread_workitem_t witem;
        pthread_workqueue_head_t headp;
        void (*func)(pthread_workqueue_t, void *);

                if ((workq->flags & PTHREAD_WORKQ_SUSPEND) == PTHREAD_WORKQ_SUSPEND) {
                        return(0);
                }
                if (TAILQ_EMPTY(&workq->item_listhead)) {
                        return(0);
                }
                witem = TAILQ_FIRST(&workq->item_listhead);
                headp = workq->headp;
                if ((witem->flags & PTH_WQITEM_BARRIER) == PTH_WQITEM_BARRIER) {
                        
                        if ((witem->flags & PTH_WQITEM_APPLIED) != 0) {
                                return(0);
                        }
                        /* Also barrier when nothing is there needs to be handled */
                        /* Nothing to wait for */
                        if (workq->kq_count != 0) {
                                witem->flags |= PTH_WQITEM_APPLIED;
                                workq->flags |= PTHREAD_WORKQ_BARRIER_ON;
                                workq->barrier_count = workq->kq_count;
#if WQ_TRACE
                        __kdebug_trace(0x9000064, 1, workq->barrier_count, 0, 0, 0);
#endif
                                return(1);
                        } else {
#if WQ_TRACE
                        __kdebug_trace(0x9000064, 2, workq->barrier_count, 0, 0, 0);
#endif
                                if (witem->func != NULL) {
                                        workqueue_list_unlock();
                                        func = witem->func;
                                        (*func)(workq, witem->func_arg);
                                        workqueue_list_lock();
                                }
                                TAILQ_REMOVE(&workq->item_listhead, witem, item_entry);
                                witem->flags = 0;
                                free_workitem(witem);
                                return(1);
                        }
                } else if ((witem->flags & PTH_WQITEM_DESTROY) == PTH_WQITEM_DESTROY) {
#if WQ_TRACE
                        __kdebug_trace(0x9000068, 1, workq->kq_count, 0, 0, 0);
#endif
                        if ((witem->flags & PTH_WQITEM_APPLIED) != 0) {
                                return(0);
                        }
                        witem->flags |= PTH_WQITEM_APPLIED;
                        workq->flags |= (PTHREAD_WORKQ_BARRIER_ON | PTHREAD_WORKQ_TERM_ON);
                        workq->barrier_count = workq->kq_count;
                        workq->term_callback = witem->func;
                        workq->term_callarg = witem->func_arg;
                        TAILQ_REMOVE(&workq->item_listhead, witem, item_entry);
                        if ((TAILQ_EMPTY(&workq->item_listhead)) && (workq->kq_count == 0)) {
                                if (!(TAILQ_EMPTY(&workq->item_kernhead))) {
#if WQ_TRACE
                                __kdebug_trace(0x900006c, workq, workq->kq_count, 0, 0xff, 0);
#endif
                                }
                                witem->flags = 0;
                                free_workitem(witem);
                                workq->flags |= PTHREAD_WORKQ_DESTROYED;
#if WQ_TRACE
                        __kdebug_trace(0x900006c, workq, workq->kq_count, 0, 1, 0);
#endif
                                headp = __pthread_wq_head_tbl[workq->queueprio];
                                if (headp->next_workq == workq) {
                                        headp->next_workq = TAILQ_NEXT(workq, wq_list);
                                        if (headp->next_workq == NULL) {
                                                headp->next_workq = TAILQ_FIRST(&headp->wqhead);
                                                if (headp->next_workq == workq)
                                                        headp->next_workq = NULL;
                                        }
                                }
                                workq->sig = 0;
                                TAILQ_REMOVE(&headp->wqhead, workq, wq_list);
                                if (workq->term_callback != NULL) {
                                        workqueue_list_unlock();
                                        (*workq->term_callback)(workq, workq->term_callarg);
                                        workqueue_list_lock();
                                }
                                free_workqueue(workq);
                                return(1);
                        } else 
                                TAILQ_INSERT_HEAD(&workq->item_listhead, witem, item_entry);
#if WQ_TRACE
                        __kdebug_trace(0x9000068, 2, workq->barrier_count, 0, 0, 0);
#endif
                        return(1);
                }  else {
#if WQ_TRACE
                        __kdebug_trace(0x9000060, witem, workq, witem->func_arg, 0xfff, 0);
#endif
                        TAILQ_REMOVE(&workq->item_listhead, witem, item_entry);
                        TAILQ_INSERT_TAIL(&workq->item_kernhead, witem, item_entry);
                        if ((witem->flags & PTH_WQITEM_KERN_COUNT) == 0) {
                                workq->kq_count++;
                                witem->flags |= PTH_WQITEM_KERN_COUNT;
                        }
                        OSAtomicIncrement32(&kernel_workq_count);
                        workqueue_list_unlock();
                        if (( error =__workq_ops(WQOPS_QUEUE_ADD, witem, 0)) == -1) {
                                OSAtomicDecrement32(&kernel_workq_count);
                                workqueue_list_lock();
#if WQ_TRACE
                        __kdebug_trace(0x900007c, witem, workq, witem->func_arg, workq->kq_count, 0);
#endif
                                TAILQ_REMOVE(&workq->item_kernhead, witem, item_entry);
                                TAILQ_INSERT_HEAD(&workq->item_listhead, witem, item_entry);
                                if ((workq->flags & (PTHREAD_WORKQ_BARRIER_ON | PTHREAD_WORKQ_TERM_ON)) != 0)
                                        workq->flags |= PTHREAD_WORKQ_REQUEUED;
                        } else
                                workqueue_list_lock();
#if WQ_TRACE
                        __kdebug_trace(0x9000060, witem, workq, witem->func_arg, workq->kq_count, 0);
#endif
                        return(1);
                }
                /* noone should come here */
#if 1
                printf("error in logic for next workitem\n");
                abort();
#endif
                return(0);
}

void
_pthread_wqthread(pthread_t self, mach_port_t kport, void * stackaddr, pthread_workitem_t item, int reuse)
{
        int ret;
        pthread_attr_t *attrs = &_pthread_attr_default;
        pthread_workqueue_t workq;
        pthread_t pself;


        workq = item->workq;
        if (reuse == 0) {
                /* reuse is set to 0, when a thread is newly created to run a workitem */
                _pthread_struct_init(self, attrs, stackaddr,  DEFAULT_STACK_SIZE, 1, 1);
                self->wqthread = 1;
                self->parentcheck = 1;

                /* These are not joinable threads */
                self->detached &= ~PTHREAD_CREATE_JOINABLE;
                self->detached |= PTHREAD_CREATE_DETACHED;
#if defined(__i386__) || defined(__x86_64__)
                _pthread_set_self(self);
#endif
#if WQ_TRACE
                __kdebug_trace(0x9000050, self, item, item->func_arg, 0, 0);
#endif
                self->kernel_thread = kport;
                self->fun = item->func;
                self->arg = item->func_arg;
                /* Add to the pthread list */
                LOCK(_pthread_list_lock);
                TAILQ_INSERT_TAIL(&__pthread_head, self, plist);
#if WQ_TRACE
                __kdebug_trace(0x900000c, self, 0, 0, 10, 0);
#endif
                _pthread_count++;
                UNLOCK(_pthread_list_lock);
        } else  {
                /* reuse is set to 1, when a thread is resued to run another work item */
#if WQ_TRACE
                __kdebug_trace(0x9000054, self, item, item->func_arg, 0, 0);
#endif
                /* reset all tsd from 1 to KEYS_MAX */
                 _pthread_tsd_reinit(self);

                self->fun = item->func;
                self->arg = item->func_arg;
        }

#if WQ_DEBUG
        if (reuse == 0) {
                pself = pthread_self();
                if (self != pself) {
#if WQ_TRACE
                __kdebug_trace(0x9000078, self, pself, item->func_arg, 0, 0);
#endif
                        printf("pthread_self not set: pself %p, passed in %p\n", pself, self);
                        _pthread_set_self(self);
                        pself = pthread_self();
                        if (self != pself)
                                printf("(2)pthread_self not set: pself %p, passed in %p\n", pself, self);
                        pself = self;
                }
        } else {
                pself = pthread_self();
                if (self != pself) {
                        printf("(3)pthread_self not set in reuse: pself %p, passed in %p\n", pself, self);
                        abort();
                }
        }
#endif /* WQ_DEBUG */

        self->cur_workq = workq;
        self->cur_workitem = item;
        OSAtomicDecrement32(&kernel_workq_count);

        ret = (*self->fun)(self->arg);

        workqueue_exit(self, workq, item);

}

static void
workqueue_exit(pthread_t self, pthread_workqueue_t workq, pthread_workitem_t item)
{
        pthread_attr_t *attrs = &_pthread_attr_default;
        pthread_workitem_t baritem;
        pthread_workqueue_head_t headp;
        void (*func)(pthread_workqueue_t, void *);
        
        workqueue_list_lock();

        TAILQ_REMOVE(&workq->item_kernhead, item, item_entry);
        workq->kq_count--;
#if WQ_TRACE
        __kdebug_trace(0x9000070, self, 1, item->func_arg, workq->kq_count, 0);
#endif
        item->flags = 0;
        free_workitem(item);

        if ((workq->flags & PTHREAD_WORKQ_BARRIER_ON) == PTHREAD_WORKQ_BARRIER_ON) {
                workq->barrier_count--;
#if WQ_TRACE
                __kdebug_trace(0x9000084, self, workq->barrier_count, workq->kq_count, 1, 0);
#endif
                if (workq->barrier_count <= 0 ) {
                        /* Need to remove barrier item from the list */
                        baritem = TAILQ_FIRST(&workq->item_listhead);
#if WQ_DEBUG
                        if ((baritem->flags & (PTH_WQITEM_BARRIER | PTH_WQITEM_DESTROY| PTH_WQITEM_APPLIED)) == 0)
                                printf("Incorect bar item being removed in barrier processing\n");
#endif /* WQ_DEBUG */
                        /* if the front item is a barrier and call back is registered, run that */
                         if (((baritem->flags & PTH_WQITEM_BARRIER) == PTH_WQITEM_BARRIER) && (baritem->func != NULL)) {
                                workqueue_list_unlock();
                                func = baritem->func;
                                (*func)(workq, baritem->func_arg);
                                workqueue_list_lock();
                        }
                        TAILQ_REMOVE(&workq->item_listhead, baritem, item_entry);
                        baritem->flags = 0;
                        free_workitem(baritem);
                        workq->flags &= ~PTHREAD_WORKQ_BARRIER_ON;
#if WQ_TRACE
                        __kdebug_trace(0x9000058, self, item, item->func_arg, 0, 0);
#endif
                        if ((workq->flags & PTHREAD_WORKQ_TERM_ON) != 0) {
                                headp = __pthread_wq_head_tbl[workq->queueprio];
                                workq->flags |= PTHREAD_WORKQ_DESTROYED;
#if WQ_TRACE
                        __kdebug_trace(0x900006c, workq, workq->kq_count, 0, 2, 0);
#endif
                                if (headp->next_workq == workq) {
                                        headp->next_workq = TAILQ_NEXT(workq, wq_list);
                                        if (headp->next_workq == NULL) {
                                                headp->next_workq = TAILQ_FIRST(&headp->wqhead);
                                                if (headp->next_workq == workq)
                                                        headp->next_workq = NULL;
                                        }
                                }
                                TAILQ_REMOVE(&headp->wqhead, workq, wq_list);
                                workq->sig = 0;
                                if (workq->term_callback != NULL) {
                                        workqueue_list_unlock();
                                        (*workq->term_callback)(workq, workq->term_callarg);
                                        workqueue_list_lock();
                                }
                                free_workqueue(workq);
                        } else {
                        /* if there are higher prio schedulabel item reset to wqreadyprio */
                                if ((workq->queueprio < wqreadyprio) && (!(TAILQ_EMPTY(&workq->item_listhead))))
                                                wqreadyprio = workq->queueprio;
                        }
                }
        } 
#if WQ_TRACE
        else {
                __kdebug_trace(0x9000070, self, 2, item->func_arg, workq->barrier_count, 0);
        }
        
        __kdebug_trace(0x900005c, self, item, 0, 0, 0);
#endif
        pick_nextworkqueue_droplock();
        _pthread_workq_return(self);
}

static void 
_pthread_workq_return(pthread_t self)
{
        struct __darwin_pthread_handler_rec *handler;
        int value = 0;
        int * value_ptr=&value;

        /* set cancel state to disable and type to deferred */
        _pthread_setcancelstate_exit(self, value_ptr, __unix_conforming);

        /* Make this thread not to receive any signals */
        __disable_threadsignal(1);

        while ((handler = self->__cleanup_stack) != 0)
        {
                (handler->__routine)(handler->__arg);
                self->__cleanup_stack = handler->__next;
        }
        _pthread_tsd_cleanup(self);

        __workq_ops(WQOPS_THREAD_RETURN, NULL, 0);

        /* This is the way to terminate the thread */
        _pthread_exit(self, NULL);
}


/* returns 0 if it handles it, otherwise 1 */
static int
handle_removeitem(pthread_workqueue_t workq, pthread_workitem_t item)
{
        pthread_workitem_t baritem;
        pthread_workqueue_head_t headp;
        void (*func)(pthread_workqueue_t, void *);

        if ((workq->flags & PTHREAD_WORKQ_BARRIER_ON) == PTHREAD_WORKQ_BARRIER_ON) {
                workq->barrier_count--;
                if (workq->barrier_count <= 0 ) {
                        /* Need to remove barrier item from the list */
                        baritem = TAILQ_FIRST(&workq->item_listhead);
#if WQ_DEBUG
                        if ((baritem->flags & (PTH_WQITEM_BARRIER | PTH_WQITEM_DESTROY| PTH_WQITEM_APPLIED)) == 0)
                                printf("Incorect bar item being removed in barrier processing\n");
#endif /* WQ_DEBUG */
                        /* if the front item is a barrier and call back is registered, run that */
                        if (((baritem->flags & PTH_WQITEM_BARRIER) == PTH_WQITEM_BARRIER) 
                                && (baritem->func != NULL)) {
                                workqueue_list_unlock();
                                func = baritem->func;
                                (*func)(workq, baritem->func_arg);
                                workqueue_list_lock();
                        }
                        TAILQ_REMOVE(&workq->item_listhead, baritem, item_entry);
                        baritem->flags = 0;
                        free_workitem(baritem);
                        item->flags = 0;
                        free_workitem(item);
                        workq->flags &= ~PTHREAD_WORKQ_BARRIER_ON;
#if WQ_TRACE
                        __kdebug_trace(0x9000058, pthread_self(), item, item->func_arg, 0, 0);
#endif
                        if ((workq->flags & PTHREAD_WORKQ_TERM_ON) != 0) {
                                headp = __pthread_wq_head_tbl[workq->queueprio];
                                workq->flags |= PTHREAD_WORKQ_DESTROYED;
#if WQ_TRACE
                                __kdebug_trace(0x900006c, workq, workq->kq_count, 0, 2, 0);
#endif
                                if (headp->next_workq == workq) {
                                        headp->next_workq = TAILQ_NEXT(workq, wq_list);
                                        if (headp->next_workq == NULL) {
                                                headp->next_workq = TAILQ_FIRST(&headp->wqhead);
                                                if (headp->next_workq == workq)
                                                        headp->next_workq = NULL;
                                        }
                                }
                                TAILQ_REMOVE(&headp->wqhead, workq, wq_list);
                                workq->sig = 0;
                                if (workq->term_callback != NULL) {
                                        workqueue_list_unlock();
                                        (*workq->term_callback)(workq, workq->term_callarg);
                                        workqueue_list_lock();
                                }
                                free_workqueue(workq);
                                pick_nextworkqueue_droplock();
                                return(0);
                        } else {
                        /* if there are higher prio schedulabel item reset to wqreadyprio */
                                if ((workq->queueprio < wqreadyprio) && (!(TAILQ_EMPTY(&workq->item_listhead))))
                                                wqreadyprio = workq->queueprio;
                                free_workitem(item);
                                pick_nextworkqueue_droplock();  
                                return(0);
                        }
                }
        }
        return(1);
}
/* XXXXXXXXXXXXX Pthread Workqueue functions XXXXXXXXXXXXXXXXXX */

int 
pthread_workqueue_create_np(pthread_workqueue_t * workqp, const pthread_workqueue_attr_t * attr)
{
        pthread_workqueue_t wq;
        pthread_workqueue_head_t headp;

        if ((attr != NULL) && (attr->sig != PTHEAD_WRKQUEUE_ATTR_SIG)) {
                return(EINVAL);
        }

        if (__is_threaded == 0)
                __is_threaded = 1;

        workqueue_list_lock();
        if (kernel_workq_setup == 0) {
                int ret = _pthread_work_internal_init();
                if (ret != 0) {
                        workqueue_list_unlock();
                        return(ret);
                }
        }
        
        wq = alloc_workqueue();
        
        _pthread_workq_init(wq, attr);

        headp = __pthread_wq_head_tbl[wq->queueprio];
        TAILQ_INSERT_TAIL(&headp->wqhead, wq, wq_list);
        if (headp->next_workq == NULL) {
                headp->next_workq = TAILQ_FIRST(&headp->wqhead);
        }

        workqueue_list_unlock();
        
        *workqp = wq;

        return(0);
}

int 
pthread_workqueue_destroy_np(pthread_workqueue_t workq, void (* callback_func)(pthread_workqueue_t, void *), void * callback_arg)
{
        pthread_workitem_t witem;
        pthread_workqueue_head_t headp;

        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }

        workqueue_list_lock();

        /*
         * Allocate the workitem here as it can drop the lock.
         * Also we can evaluate the workqueue state only once.
         */
        witem = alloc_workitem();
        witem->item_entry.tqe_next = 0;
        witem->item_entry.tqe_prev = 0;
        witem->func = callback_func;
        witem->func_arg = callback_arg;
        witem->flags = PTH_WQITEM_DESTROY;

        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_TERM_ON | PTHREAD_WORKQ_DESTROYED)) == 0) {
                workq->flags |= PTHREAD_WORKQ_IN_TERMINATE;
                /* If nothing queued or running, destroy now */
                if ((TAILQ_EMPTY(&workq->item_listhead)) && (TAILQ_EMPTY(&workq->item_kernhead))) {
                        workq->flags |= (PTHREAD_WORKQ_TERM_ON | PTHREAD_WORKQ_DESTROYED);
                        headp = __pthread_wq_head_tbl[workq->queueprio];
                        workq->term_callback = callback_func;
                        workq->term_callarg = callback_arg;
                        if (headp->next_workq == workq) {
                                headp->next_workq = TAILQ_NEXT(workq, wq_list);
                                if (headp->next_workq == NULL) {
                                        headp->next_workq = TAILQ_FIRST(&headp->wqhead);
                                        if (headp->next_workq == workq)
                                                headp->next_workq = NULL;
                                }
                        }
                        TAILQ_REMOVE(&headp->wqhead, workq, wq_list);
                        workq->sig = 0;
                        free_workitem(witem);
                        if (workq->term_callback != NULL) {
                                workqueue_list_unlock();
                                (*workq->term_callback)(workq, workq->term_callarg);
                                workqueue_list_lock();
                        }
#if WQ_TRACE
                        __kdebug_trace(0x900006c, workq, workq->kq_count, 0, 3, 0);
#endif
                        free_workqueue(workq);
                        workqueue_list_unlock();
                        return(0);
                }
                TAILQ_INSERT_TAIL(&workq->item_listhead, witem, item_entry);
        } else {
                free_workitem(witem);
                workqueue_list_unlock();
                return(EINPROGRESS);
        }
        workqueue_list_unlock();
        return(0);
}


int 
pthread_workqueue_additem_np(pthread_workqueue_t workq, void ( *workitem_func)(void *), void * workitem_arg, pthread_workitem_handle_t * itemhandlep)
{
        pthread_workitem_t witem;

        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }

        workqueue_list_lock();

        /*
         * Allocate the workitem here as it can drop the lock.
         * Also we can evaluate the workqueue state only once.
         */
        witem = alloc_workitem();
        witem->func = workitem_func;
        witem->func_arg = workitem_arg;
        witem->flags = 0;
        witem->workq = workq;
        witem->item_entry.tqe_next = 0;
        witem->item_entry.tqe_prev = 0;

        /* alloc workitem can drop the lock, check the state  */
        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_DESTROYED)) != 0) {
                free_workitem(witem);
                workqueue_list_unlock();
                *itemhandlep = 0;
                return(ESRCH);
        }

        if (itemhandlep != NULL)
                *itemhandlep = (pthread_workitem_handle_t *)witem;
        TAILQ_INSERT_TAIL(&workq->item_listhead, witem, item_entry);
        if (((workq->flags & PTHREAD_WORKQ_BARRIER_ON) == 0) && (workq->queueprio < wqreadyprio))
                        wqreadyprio = workq->queueprio;

        pick_nextworkqueue_droplock();

        return(0);
}

int 
pthread_workqueue_removeitem_np(pthread_workqueue_t workq, pthread_workitem_handle_t itemhandle)
{
        pthread_workitem_t item, baritem;
        pthread_workqueue_head_t headp;
        int error;
        
        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }

        workqueue_list_lock();
        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_DESTROYED)) != 0) {
                workqueue_list_unlock();
                return(ESRCH);
        }

        TAILQ_FOREACH(item, &workq->item_listhead, item_entry) {
                if (item == (pthread_workitem_t)itemhandle) {
                        TAILQ_REMOVE(&workq->item_listhead, item, item_entry);
                        if ((item->flags & (PTH_WQITEM_BARRIER | PTH_WQITEM_APPLIED)) == (PTH_WQITEM_BARRIER | PTH_WQITEM_APPLIED)) {
                                workq->flags &= ~PTHREAD_WORKQ_BARRIER_ON;
                                workq->barrier_count = 0;
                                if ((workq->queueprio < wqreadyprio) && (!(TAILQ_EMPTY(&workq->item_listhead)))) {
                                                wqreadyprio = workq->queueprio;
                                }
                        } else if ((item->flags & PTH_WQITEM_KERN_COUNT) == PTH_WQITEM_KERN_COUNT) {
                                workq->kq_count--;
                                item->flags |= PTH_WQITEM_REMOVED;      
                                if (handle_removeitem(workq, item) == 0)
                                        return(0);
                        }
                        item->flags |= PTH_WQITEM_NOTINLIST;
                        free_workitem(item);
                        workqueue_list_unlock();
                        return(0);
                }
        }
                        
        TAILQ_FOREACH(item, &workq->item_kernhead, item_entry) {
                if (item == (pthread_workitem_t)itemhandle) {
                                workqueue_list_unlock();
                                if ((error = __workq_ops(WQOPS_QUEUE_REMOVE, item, 0)) == 0) {
                                        workqueue_list_lock();
                                        TAILQ_REMOVE(&workq->item_kernhead, item, item_entry);
                                        OSAtomicDecrement32(&kernel_workq_count);
                                        workq->kq_count--; 
                                        item->flags |= PTH_WQITEM_REMOVED;      
                                        if (handle_removeitem(workq, item) != 0) {
                                                free_workitem(item);
                                                pick_nextworkqueue_droplock();
                                        }
                                        return(0);
                                } else {
                                        workqueue_list_unlock();
                                        return(EBUSY);
                                }
                } 
        }
        workqueue_list_unlock();
        return(EINVAL);
}


int 
pthread_workqueue_addbarrier_np(pthread_workqueue_t workq, void (* callback_func)(pthread_workqueue_t, void *), void * callback_arg, __unused int waitforcallback, pthread_workitem_handle_t *itemhandlep)
{
        pthread_workitem_t witem;

        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }

        workqueue_list_lock();

        /*
         * Allocate the workitem here as it can drop the lock.
         * Also we can evaluate the workqueue state only once.
         */
        witem = alloc_workitem();
        witem->item_entry.tqe_next = 0;
        witem->item_entry.tqe_prev = 0;
        witem->func = callback_func;
        witem->func_arg = callback_arg;
        witem->flags = PTH_WQITEM_BARRIER;

        /* alloc workitem can drop the lock, check the state  */
        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_DESTROYED)) != 0) {
                free_workitem(witem);
                workqueue_list_unlock();
                return(ESRCH);
        }

        if (itemhandlep != NULL)
                *itemhandlep = (pthread_workitem_handle_t *)witem;

        TAILQ_INSERT_TAIL(&workq->item_listhead, witem, item_entry);
        if (((workq->flags & PTHREAD_WORKQ_BARRIER_ON) == 0) && (workq->queueprio < wqreadyprio))
                        wqreadyprio = workq->queueprio;

        pick_nextworkqueue_droplock();

        return(0);
}

int 
pthread_workqueue_suspend_np(pthread_workqueue_t workq)
{
        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }
        workqueue_list_lock();
        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_DESTROYED)) != 0) {
                workqueue_list_unlock();
                return(ESRCH);
        }

        workq->flags |= PTHREAD_WORKQ_SUSPEND;
        workq->suspend_count++;
        workqueue_list_unlock();
        return(0);
}

int 
pthread_workqueue_resume_np(pthread_workqueue_t workq)
{
        if (valid_workq(workq) == 0) {
                return(EINVAL);
        }
        workqueue_list_lock();
        if ((workq->flags & (PTHREAD_WORKQ_IN_TERMINATE | PTHREAD_WORKQ_DESTROYED)) != 0) {
                workqueue_list_unlock();
                return(ESRCH);
        }

        workq->suspend_count--;
        if (workq->suspend_count <= 0) {
                workq->flags &= ~PTHREAD_WORKQ_SUSPEND;
                if (((workq->flags & PTHREAD_WORKQ_BARRIER_ON) == 0) && (workq->queueprio < wqreadyprio))
                                wqreadyprio = workq->queueprio;

                        pick_nextworkqueue_droplock();
        } else
                workqueue_list_unlock();


        return(0);
}

#else /* !BUILDING_VARIANT ] [ */
extern int __unix_conforming;
extern int _pthread_count;
extern pthread_lock_t _pthread_list_lock;
extern void _pthread_testcancel(pthread_t thread, int isconforming);
extern int _pthread_reap_thread(pthread_t th, mach_port_t kernel_thread, void **value_ptr, int conforming);

#endif /* !BUILDING_VARIANT ] */

#if __DARWIN_UNIX03

__private_extern__ void 
__posix_join_cleanup(void *arg)
{
        pthread_t thread = (pthread_t)arg;
        int already_exited, res;
        void * dummy;
        semaphore_t death;
        mach_port_t joinport;
        int newstyle = 0;

        LOCK(thread->lock);
        already_exited = (thread->detached & _PTHREAD_EXITED);

        newstyle = thread->newstyle;
        
#if WQ_TRACE
        __kdebug_trace(0x900002c, thread, newstyle, 0, 0, 0);
#endif
        if (newstyle = 0) {
                death = thread->death;
                if (!already_exited){
                        thread->joiner = (struct _pthread *)NULL;
                        UNLOCK(thread->lock);
                        restore_sem_to_pool(death);
                } else {
                        UNLOCK(thread->lock);
                        while ((res = _pthread_reap_thread(thread,
                                        thread->kernel_thread,
                                        &dummy, 1)) == EAGAIN)
                                {
                                        sched_yield();
                                }
                        restore_sem_to_pool(death);

                }

        } else {
                /* leave another thread to join */
                thread->joiner = (struct _pthread *)NULL;
                UNLOCK(thread->lock);
        }
}

#endif /* __DARWIN_UNIX03 */


/*
 * Wait for a thread to terminate and obtain its exit value.
 */
/*
int       
pthread_join(pthread_t thread, 
             void **value_ptr)

moved to pthread_cancelable.c */

/*
 * Cancel a thread
 */
int
pthread_cancel(pthread_t thread)
{
#if __DARWIN_UNIX03
        if (__unix_conforming == 0)
                __unix_conforming = 1;
#endif /* __DARWIN_UNIX03 */

        if (_pthread_lookup_thread(thread, NULL, 0) != 0)
                return(ESRCH);

#if __DARWIN_UNIX03
        int state;

        LOCK(thread->lock);
        state = thread->cancel_state |= _PTHREAD_CANCEL_PENDING;
        UNLOCK(thread->lock);
        if (state & PTHREAD_CANCEL_ENABLE)
                __pthread_markcancel(thread->kernel_thread);
#else /* __DARWIN_UNIX03 */
        thread->cancel_state |= _PTHREAD_CANCEL_PENDING;
#endif /* __DARWIN_UNIX03 */
        return (0);
}

void
pthread_testcancel(void)
{
        pthread_t self = pthread_self();

#if __DARWIN_UNIX03
        if (__unix_conforming == 0)
                __unix_conforming = 1;
        _pthread_testcancel(self, 1);
#else /* __DARWIN_UNIX03 */
        _pthread_testcancel(self, 0);
#endif /* __DARWIN_UNIX03 */

}


/*
 * Query/update the cancelability 'state' of a thread
 */
int
pthread_setcancelstate(int state, int *oldstate)
{
#if __DARWIN_UNIX03
        if (__unix_conforming == 0) {
                __unix_conforming = 1;
        }
        return (_pthread_setcancelstate_internal(state, oldstate, 1));
#else /* __DARWIN_UNIX03 */
        return (_pthread_setcancelstate_internal(state, oldstate, 0));
#endif /* __DARWIN_UNIX03 */

}



/*
 * Query/update the cancelability 'type' of a thread
 */
int
pthread_setcanceltype(int type, int *oldtype)
{
        pthread_t self = pthread_self();
        
#if __DARWIN_UNIX03
        if (__unix_conforming == 0)
                __unix_conforming = 1;
#endif /* __DARWIN_UNIX03 */

        if ((type != PTHREAD_CANCEL_DEFERRED) && 
            (type != PTHREAD_CANCEL_ASYNCHRONOUS))
                return EINVAL;
        self = pthread_self();
        LOCK(self->lock);
        if (oldtype)
                *oldtype = self->cancel_state & _PTHREAD_CANCEL_TYPE_MASK;
        self->cancel_state &= ~_PTHREAD_CANCEL_TYPE_MASK;
        self->cancel_state |= type;
        UNLOCK(self->lock);
#if !__DARWIN_UNIX03
        _pthread_testcancel(self, 0);  /* See if we need to 'die' now... */
#endif /* __DARWIN_UNIX03 */
        return (0);
}

int 
pthread_sigmask(int how, const sigset_t * set, sigset_t * oset)
{
#if __DARWIN_UNIX03
        int err = 0;

        if (__pthread_sigmask(how, set, oset) == -1) {
                err = errno;
        } 
        return(err);
#else /* __DARWIN_UNIX03 */
        return(__pthread_sigmask(how, set, oset));
#endif /* __DARWIN_UNIX03 */
}

/*
int
sigwait(const sigset_t * set, int * sig)

moved to pthread_cancelable.c */