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|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Netscape Portable Runtime (NSPR).
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998-2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <kernel/OS.h>
#include <support/TLS.h>
#include "prlog.h"
#include "primpl.h"
#include "prcvar.h"
#include "prpdce.h"
#include <stdlib.h>
#include <string.h>
#include <signal.h>
/* values for PRThread.state */
#define BT_THREAD_PRIMORD 0x01 /* this is the primordial thread */
#define BT_THREAD_SYSTEM 0x02 /* this is a system thread */
#define BT_THREAD_JOINABLE 0x04 /* this is a joinable thread */
struct _BT_Bookeeping
{
PRLock *ml; /* a lock to protect ourselves */
sem_id cleanUpSem; /* the primoridal thread will block on this
sem while waiting for the user threads */
PRInt32 threadCount; /* user thred count */
} bt_book = { NULL, B_ERROR, 0 };
#define BT_TPD_LIMIT 128 /* number of TPD slots we'll provide (arbitrary) */
/* these will be used to map an index returned by PR_NewThreadPrivateIndex()
to the corresponding beos native TLS slot number, and to the destructor
for that slot - note that, because it is allocated globally, this data
will be automatically zeroed for us when the program begins */
static int32 tpd_beosTLSSlots[BT_TPD_LIMIT];
static PRThreadPrivateDTOR tpd_dtors[BT_TPD_LIMIT];
static vint32 tpd_slotsUsed=0; /* number of currently-allocated TPD slots */
static int32 tls_prThreadSlot; /* TLS slot in which PRThread will be stored */
/* this mutex will be used to synchronize access to every
PRThread.md.joinSem and PRThread.md.is_joining (we could
actually allocate one per thread, but that seems a bit excessive,
especially considering that there will probably be little
contention, PR_JoinThread() is allowed to block anyway, and the code
protected by the mutex is short/fast) */
static PRLock *joinSemLock;
static PRUint32 _bt_MapNSPRToNativePriority( PRThreadPriority priority );
static PRThreadPriority _bt_MapNativeToNSPRPriority( PRUint32 priority );
static void _bt_CleanupThread(void *arg);
static PRThread *_bt_AttachThread();
void
_PR_InitThreads (PRThreadType type, PRThreadPriority priority,
PRUintn maxPTDs)
{
PRThread *primordialThread;
PRUint32 beThreadPriority;
/* allocate joinSem mutex */
joinSemLock = PR_NewLock();
if (joinSemLock == NULL)
{
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
return;
}
/*
** Create and initialize NSPR structure for our primordial thread.
*/
primordialThread = PR_NEWZAP(PRThread);
if( NULL == primordialThread )
{
PR_SetError( PR_OUT_OF_MEMORY_ERROR, 0 );
return;
}
primordialThread->md.joinSem = B_ERROR;
/*
** Set the priority to the desired level.
*/
beThreadPriority = _bt_MapNSPRToNativePriority( priority );
set_thread_priority( find_thread( NULL ), beThreadPriority );
primordialThread->priority = priority;
/* set the thread's state - note that the thread is not joinable */
primordialThread->state |= BT_THREAD_PRIMORD;
if (type == PR_SYSTEM_THREAD)
primordialThread->state |= BT_THREAD_SYSTEM;
/*
** Allocate a TLS slot for the PRThread structure (just using
** native TLS, as opposed to NSPR TPD, will make PR_GetCurrentThread()
** somewhat faster, and will leave one more TPD slot for our client)
*/
tls_prThreadSlot = tls_allocate();
/*
** Stuff our new PRThread structure into our thread specific
** slot.
*/
tls_set(tls_prThreadSlot, primordialThread);
/* allocate lock for bt_book */
bt_book.ml = PR_NewLock();
if( NULL == bt_book.ml )
{
PR_SetError( PR_OUT_OF_MEMORY_ERROR, 0 );
return;
}
}
PRUint32
_bt_MapNSPRToNativePriority( PRThreadPriority priority )
{
switch( priority )
{
case PR_PRIORITY_LOW: return( B_LOW_PRIORITY );
case PR_PRIORITY_NORMAL: return( B_NORMAL_PRIORITY );
case PR_PRIORITY_HIGH: return( B_DISPLAY_PRIORITY );
case PR_PRIORITY_URGENT: return( B_URGENT_DISPLAY_PRIORITY );
default: return( B_NORMAL_PRIORITY );
}
}
PRThreadPriority
_bt_MapNativeToNSPRPriority(PRUint32 priority)
{
if (priority < B_NORMAL_PRIORITY)
return PR_PRIORITY_LOW;
if (priority < B_DISPLAY_PRIORITY)
return PR_PRIORITY_NORMAL;
if (priority < B_URGENT_DISPLAY_PRIORITY)
return PR_PRIORITY_HIGH;
return PR_PRIORITY_URGENT;
}
PRUint32
_bt_mapNativeToNSPRPriority( int32 priority )
{
switch( priority )
{
case PR_PRIORITY_LOW: return( B_LOW_PRIORITY );
case PR_PRIORITY_NORMAL: return( B_NORMAL_PRIORITY );
case PR_PRIORITY_HIGH: return( B_DISPLAY_PRIORITY );
case PR_PRIORITY_URGENT: return( B_URGENT_DISPLAY_PRIORITY );
default: return( B_NORMAL_PRIORITY );
}
}
/* This method is called by all NSPR threads as they exit */
void _bt_CleanupThread(void *arg)
{
PRThread *me = PR_GetCurrentThread();
int32 i;
/* first, clean up all thread-private data */
for (i = 0; i < tpd_slotsUsed; i++)
{
void *oldValue = tls_get(tpd_beosTLSSlots[i]);
if ( oldValue != NULL && tpd_dtors[i] != NULL )
(*tpd_dtors[i])(oldValue);
}
/* if this thread is joinable, wait for someone to join it */
if (me->state & BT_THREAD_JOINABLE)
{
/* protect access to our joinSem */
PR_Lock(joinSemLock);
if (me->md.is_joining)
{
/* someone is already waiting to join us (they've
allocated a joinSem for us) - let them know we're
ready */
delete_sem(me->md.joinSem);
PR_Unlock(joinSemLock);
}
else
{
/* noone is currently waiting for our demise - it
is our responsibility to allocate the joinSem
and block on it */
me->md.joinSem = create_sem(0, "join sem");
/* we're done accessing our joinSem */
PR_Unlock(joinSemLock);
/* wait for someone to join us */
while (acquire_sem(me->md.joinSem) == B_INTERRUPTED);
}
}
/* if this is a user thread, we must update our books */
if ((me->state & BT_THREAD_SYSTEM) == 0)
{
/* synchronize access to bt_book */
PR_Lock( bt_book.ml );
/* decrement the number of currently-alive user threads */
bt_book.threadCount--;
if (bt_book.threadCount == 0 && bt_book.cleanUpSem != B_ERROR) {
/* we are the last user thread, and the primordial thread is
blocked in PR_Cleanup() waiting for us to finish - notify
it */
delete_sem(bt_book.cleanUpSem);
}
PR_Unlock( bt_book.ml );
}
/* finally, delete this thread's PRThread */
PR_DELETE(me);
}
/**
* This is a wrapper that all threads invoke that allows us to set some
* things up prior to a thread's invocation and clean up after a thread has
* exited.
*/
static void*
_bt_root (void* arg)
{
PRThread *thred = (PRThread*)arg;
PRIntn rv;
void *privData;
status_t result;
int i;
/* save our PRThread object into our TLS */
tls_set(tls_prThreadSlot, thred);
thred->startFunc(thred->arg); /* run the dang thing */
/* clean up */
_bt_CleanupThread(NULL);
return 0;
}
PR_IMPLEMENT(PRThread*)
PR_CreateThread (PRThreadType type, void (*start)(void* arg), void* arg,
PRThreadPriority priority, PRThreadScope scope,
PRThreadState state, PRUint32 stackSize)
{
PRUint32 bePriority;
PRThread* thred;
if (!_pr_initialized) _PR_ImplicitInitialization();
thred = PR_NEWZAP(PRThread);
if (thred == NULL)
{
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
return NULL;
}
thred->md.joinSem = B_ERROR;
thred->arg = arg;
thred->startFunc = start;
thred->priority = priority;
if( state == PR_JOINABLE_THREAD )
{
thred->state |= BT_THREAD_JOINABLE;
}
/* keep some books */
PR_Lock( bt_book.ml );
if (type == PR_USER_THREAD)
{
bt_book.threadCount++;
}
PR_Unlock( bt_book.ml );
bePriority = _bt_MapNSPRToNativePriority( priority );
thred->md.tid = spawn_thread((thread_func)_bt_root, "moz-thread",
bePriority, thred);
if (thred->md.tid < B_OK) {
PR_SetError(PR_UNKNOWN_ERROR, thred->md.tid);
PR_DELETE(thred);
return NULL;
}
if (resume_thread(thred->md.tid) < B_OK) {
PR_SetError(PR_UNKNOWN_ERROR, 0);
PR_DELETE(thred);
return NULL;
}
return thred;
}
PR_IMPLEMENT(PRThread*)
PR_AttachThread(PRThreadType type, PRThreadPriority priority,
PRThreadStack *stack)
{
/* PR_GetCurrentThread() will attach a thread if necessary */
return PR_GetCurrentThread();
}
PR_IMPLEMENT(void)
PR_DetachThread()
{
/* we don't support detaching */
}
PR_IMPLEMENT(PRStatus)
PR_JoinThread (PRThread* thred)
{
status_t eval, status;
PR_ASSERT(thred != NULL);
if ((thred->state & BT_THREAD_JOINABLE) == 0)
{
PR_SetError( PR_INVALID_ARGUMENT_ERROR, 0 );
return( PR_FAILURE );
}
/* synchronize access to the thread's joinSem */
PR_Lock(joinSemLock);
if (thred->md.is_joining)
{
/* another thread is already waiting to join the specified
thread - we must fail */
PR_Unlock(joinSemLock);
return PR_FAILURE;
}
/* let others know we are waiting to join */
thred->md.is_joining = PR_TRUE;
if (thred->md.joinSem == B_ERROR)
{
/* the thread hasn't finished yet - it is our responsibility to
allocate a joinSem and wait on it */
thred->md.joinSem = create_sem(0, "join sem");
/* we're done changing the joinSem now */
PR_Unlock(joinSemLock);
/* wait for the thread to finish */
while (acquire_sem(thred->md.joinSem) == B_INTERRUPTED);
}
else
{
/* the thread has already finished, and has allocated the
joinSem itself - let it know it can finally die */
delete_sem(thred->md.joinSem);
PR_Unlock(joinSemLock);
}
/* make sure the thread is dead */
wait_for_thread(thred->md.tid, &eval);
return PR_SUCCESS;
}
PR_IMPLEMENT(PRThread*)
PR_GetCurrentThread ()
{
PRThread* thred;
if (!_pr_initialized) _PR_ImplicitInitialization();
thred = (PRThread *)tls_get( tls_prThreadSlot);
if (thred == NULL)
{
/* this thread doesn't have a PRThread structure (it must be
a native thread not created by the NSPR) - assimilate it */
thred = _bt_AttachThread();
}
PR_ASSERT(NULL != thred);
return thred;
}
PR_IMPLEMENT(PRThreadScope)
PR_GetThreadScope (const PRThread* thred)
{
PR_ASSERT(thred != NULL);
return PR_GLOBAL_THREAD;
}
PR_IMPLEMENT(PRThreadType)
PR_GetThreadType (const PRThread* thred)
{
PR_ASSERT(thred != NULL);
return (thred->state & BT_THREAD_SYSTEM) ?
PR_SYSTEM_THREAD : PR_USER_THREAD;
}
PR_IMPLEMENT(PRThreadState)
PR_GetThreadState (const PRThread* thred)
{
PR_ASSERT(thred != NULL);
return (thred->state & BT_THREAD_JOINABLE)?
PR_JOINABLE_THREAD: PR_UNJOINABLE_THREAD;
}
PR_IMPLEMENT(PRThreadPriority)
PR_GetThreadPriority (const PRThread* thred)
{
PR_ASSERT(thred != NULL);
return thred->priority;
} /* PR_GetThreadPriority */
PR_IMPLEMENT(void) PR_SetThreadPriority(PRThread *thred,
PRThreadPriority newPri)
{
PRUint32 bePriority;
PR_ASSERT( thred != NULL );
thred->priority = newPri;
bePriority = _bt_MapNSPRToNativePriority( newPri );
set_thread_priority( thred->md.tid, bePriority );
}
PR_IMPLEMENT(PRStatus)
PR_NewThreadPrivateIndex (PRUintn* newIndex,
PRThreadPrivateDTOR destructor)
{
int32 index;
if (!_pr_initialized) _PR_ImplicitInitialization();
/* reserve the next available tpd slot */
index = atomic_add( &tpd_slotsUsed, 1 );
if (index >= BT_TPD_LIMIT)
{
/* no slots left - decrement value, then fail */
atomic_add( &tpd_slotsUsed, -1 );
PR_SetError( PR_TPD_RANGE_ERROR, 0 );
return( PR_FAILURE );
}
/* allocate a beos-native TLS slot for this index (the new slot
automatically contains NULL) */
tpd_beosTLSSlots[index] = tls_allocate();
/* remember the destructor */
tpd_dtors[index] = destructor;
*newIndex = (PRUintn)index;
return( PR_SUCCESS );
}
PR_IMPLEMENT(PRStatus)
PR_SetThreadPrivate (PRUintn index, void* priv)
{
void *oldValue;
/*
** Sanity checking
*/
if(index < 0 || index >= tpd_slotsUsed || index >= BT_TPD_LIMIT)
{
PR_SetError( PR_TPD_RANGE_ERROR, 0 );
return( PR_FAILURE );
}
/* if the old value isn't NULL, and the dtor for this slot isn't
NULL, we must destroy the data */
oldValue = tls_get(tpd_beosTLSSlots[index]);
if (oldValue != NULL && tpd_dtors[index] != NULL)
(*tpd_dtors[index])(oldValue);
/* save new value */
tls_set(tpd_beosTLSSlots[index], priv);
return( PR_SUCCESS );
}
PR_IMPLEMENT(void*)
PR_GetThreadPrivate (PRUintn index)
{
/* make sure the index is valid */
if (index < 0 || index >= tpd_slotsUsed || index >= BT_TPD_LIMIT)
{
PR_SetError( PR_TPD_RANGE_ERROR, 0 );
return NULL;
}
/* return the value */
return tls_get( tpd_beosTLSSlots[index] );
}
PR_IMPLEMENT(PRStatus)
PR_Interrupt (PRThread* thred)
{
PRIntn rv;
PR_ASSERT(thred != NULL);
/*
** there seems to be a bug in beos R5 in which calling
** resume_thread() on a blocked thread returns B_OK instead
** of B_BAD_THREAD_STATE (beos bug #20000422-19095). as such,
** to interrupt a thread, we will simply suspend then resume it
** (no longer call resume_thread(), check for B_BAD_THREAD_STATE,
** the suspend/resume to wake up a blocked thread). this wakes
** up blocked threads properly, and doesn't hurt unblocked threads
** (they simply get stopped then re-started immediately)
*/
rv = suspend_thread( thred->md.tid );
if( rv != B_NO_ERROR )
{
/* this doesn't appear to be a valid thread_id */
PR_SetError( PR_UNKNOWN_ERROR, rv );
return PR_FAILURE;
}
rv = resume_thread( thred->md.tid );
if( rv != B_NO_ERROR )
{
PR_SetError( PR_UNKNOWN_ERROR, rv );
return PR_FAILURE;
}
return PR_SUCCESS;
}
PR_IMPLEMENT(void)
PR_ClearInterrupt ()
{
}
PR_IMPLEMENT(PRStatus)
PR_Yield ()
{
/* we just sleep for long enough to cause a reschedule (100
microseconds) */
snooze(100);
}
#define BT_MILLION 1000000UL
PR_IMPLEMENT(PRStatus)
PR_Sleep (PRIntervalTime ticks)
{
bigtime_t tps;
status_t status;
if (!_pr_initialized) _PR_ImplicitInitialization();
tps = PR_IntervalToMicroseconds( ticks );
status = snooze(tps);
if (status == B_NO_ERROR) return PR_SUCCESS;
PR_SetError(PR_NOT_IMPLEMENTED_ERROR, status);
return PR_FAILURE;
}
PR_IMPLEMENT(PRStatus)
PR_Cleanup ()
{
PRThread *me = PR_CurrentThread();
PR_ASSERT(me->state & BT_THREAD_PRIMORD);
if ((me->state & BT_THREAD_PRIMORD) == 0) {
return PR_FAILURE;
}
PR_Lock( bt_book.ml );
if (bt_book.threadCount != 0)
{
/* we'll have to wait for some threads to finish - create a
sem to block on */
bt_book.cleanUpSem = create_sem(0, "cleanup sem");
}
PR_Unlock( bt_book.ml );
/* note that, if all the user threads were already dead, we
wouldn't have created a sem above, so this acquire_sem()
will fail immediately */
while (acquire_sem(bt_book.cleanUpSem) == B_INTERRUPTED);
return PR_SUCCESS;
}
PR_IMPLEMENT(void)
PR_ProcessExit (PRIntn status)
{
exit(status);
}
PRThread *_bt_AttachThread()
{
PRThread *thread;
thread_info tInfo;
/* make sure this thread doesn't already have a PRThread structure */
PR_ASSERT(tls_get(tls_prThreadSlot) == NULL);
/* allocate a PRThread structure for this thread */
thread = PR_NEWZAP(PRThread);
if (thread == NULL)
{
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
return NULL;
}
/* get the native thread's current state */
get_thread_info(find_thread(NULL), &tInfo);
/* initialize new PRThread */
thread->md.tid = tInfo.thread;
thread->md.joinSem = B_ERROR;
thread->priority = _bt_MapNativeToNSPRPriority(tInfo.priority);
/* attached threads are always non-joinable user threads */
thread->state = 0;
/* increment user thread count */
PR_Lock(bt_book.ml);
bt_book.threadCount++;
PR_Unlock(bt_book.ml);
/* store this thread's PRThread */
tls_set(tls_prThreadSlot, thread);
/* the thread must call _bt_CleanupThread() before it dies, in order
to clean up its PRThread, synchronize with the primordial thread,
etc. */
on_exit_thread(_bt_CleanupThread, NULL);
return thread;
}
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