int pthread_create (pthread_t * tid,
const pthread_attr_t * attr,
void *(*start) (void *), void *arg)
/*
* ------------------------------------------------------
* DOCPUBLIC
* This function creates a thread running the start function,
* passing it the parameter value, 'arg'. The 'attr'
* argument specifies optional creation attributes.
* The identity of the new thread is returned
* via 'tid', which should not be NULL.
*
* PARAMETERS
* tid
* pointer to an instance of pthread_t
*
* attr
* optional pointer to an instance of pthread_attr_t
*
* start
* pointer to the starting routine for the new thread
*
* arg
* optional parameter passed to 'start'
*
*
* DESCRIPTION
* This function creates a thread running the start function,
* passing it the parameter value, 'arg'. The 'attr'
* argument specifies optional creation attributes.
* The identity of the new thread is returned
* via 'tid', which should not be the NULL pointer.
*
* RESULTS
* 0 successfully created thread,
* EINVAL attr invalid,
* EAGAIN insufficient resources.
*
* ------------------------------------------------------
*/
{
pthread_t thread;
pte_thread_t * tp;
int result = EAGAIN;
int run = PTE_TRUE;
ThreadParms *parms = NULL;
long stackSize;
int priority = 0;
pthread_t self;
pte_osResult osResult;
register pthread_attr_t a = NULL;
/*
* Before doing anything, check that tid can be stored through
* without invoking a memory protection error (segfault).
* Make sure that the assignment below can't be optimised out by the compiler.
* This is assured by conditionally assigning *tid again at the end.
*/
if (attr != NULL)
a = *attr;
if ((thread = pte_new ()) == NULL)
goto FAIL0;
tp = (pte_thread_t *) thread;
priority = tp->sched_priority;
if ((parms = (ThreadParms *) malloc (sizeof (*parms))) == NULL)
goto FAIL0;
parms->tid = thread;
parms->start = start;
parms->arg = arg;
if (a != NULL)
{
stackSize = a->stacksize;
tp->detachState = a->detachstate;
priority = a->param.sched_priority;
if ( (priority > pte_osThreadGetMaxPriority()) ||
(priority < pte_osThreadGetMinPriority()) )
{
result = EINVAL;
goto FAIL0;
}
/* Everything else */
/*
* Thread priority must be set to a valid system level
* without altering the value set by pthread_attr_setschedparam().
*/
if (PTHREAD_INHERIT_SCHED == a->inheritsched)
{
/*
* If the thread that called pthread_create() is an OS thread
* then the inherited priority could be the result of a temporary
* system adjustment. This is not the case for POSIX threads.
*/
self = pthread_self ();
priority = ((pte_thread_t *) self)->sched_priority;
}
}
else
{
/*
* Default stackSize
*/
stackSize = PTHREAD_STACK_MIN;
}
tp->state = run ? PThreadStateInitial : PThreadStateSuspended;
tp->keys = NULL;
/*
* Threads must be started in suspended mode and resumed if necessary
* after _beginthreadex returns us the handle. Otherwise we set up a
* race condition between the creating and the created threads.
* Note that we also retain a local copy of the handle for use
* by us in case thread.p->threadH gets NULLed later but before we've
* finished with it here.
*/
result = pthread_mutex_lock (&tp->threadLock);
if (result == 0)
{
/*
* Must record the thread's sched_priority as given,
* not as finally adjusted.
*/
tp->sched_priority = priority;
(void) pthread_mutex_unlock (&tp->threadLock);
}
osResult = pte_osThreadCreate(pte_threadStart,
stackSize,
priority,
parms,
&(tp->threadId));
if (osResult == PTE_OS_OK)
{
pte_osThreadStart(tp->threadId);
result = 0;
}
else
{
tp->threadId = 0;
result = EAGAIN;
goto FAIL0;
}
/*
* Fall Through Intentionally
*/
/*
* ------------
* Failure Code
* ------------
*/
FAIL0:
if (result != 0)
{
pte_threadDestroy (thread);
tp = NULL;
if (parms != NULL)
free (parms);
}
else
{
if (tid != NULL)
*tid = thread;
}
return (result);
}
int
pthread_detach (pthread_t thread)
/*
* ------------------------------------------------------
* DOCPUBLIC
* This function detaches the given thread.
*
* PARAMETERS
* thread
* an instance of a pthread_t
*
*
* DESCRIPTION
* This function detaches the given thread. You may use it to
* detach the main thread or to detach a joinable thread.
* NOTE: detached threads cannot be joined;
* storage is freed immediately on termination.
*
* RESULTS
* 0 successfully detached the thread,
* EINVAL thread is not a joinable thread,
* ENOSPC a required resource has been exhausted,
* ESRCH no thread could be found for 'thread',
*
* ------------------------------------------------------
*/
{
int result;
unsigned char destroyIt = PTE_FALSE;
pte_thread_t * tp = (pte_thread_t *) thread.p;
pte_osMutexLock (pte_thread_reuse_lock);
if (NULL == tp
|| thread.x != tp->ptHandle.x)
{
result = ESRCH;
}
else if (PTHREAD_CREATE_DETACHED == tp->detachState)
{
result = EINVAL;
}
else
{
/*
* Joinable pte_thread_t structs are not scavenged until
* a join or detach is done. The thread may have exited already,
* but all of the state and locks etc are still there.
*/
result = 0;
if (pthread_mutex_lock (&tp->cancelLock) == 0)
{
if (tp->state != PThreadStateLast)
{
tp->detachState = PTHREAD_CREATE_DETACHED;
}
else if (tp->detachState != PTHREAD_CREATE_DETACHED)
{
/*
* Thread is joinable and has exited or is exiting.
*/
destroyIt = PTE_TRUE;
}
(void) pthread_mutex_unlock (&tp->cancelLock);
}
else
{
/* cancelLock shouldn't fail, but if it does ... */
result = ESRCH;
}
}
pte_osMutexUnlock(pte_thread_reuse_lock);
if (result == 0)
{
/* Thread is joinable */
if (destroyIt)
{
/* The thread has exited or is exiting but has not been joined or
* detached. Need to wait in case it's still exiting.
*/
pte_osThreadWaitForEnd(tp->threadId);
pte_threadDestroy (thread);
}
}
return (result);
} /* pthread_detach */
