The Tor Browser: nsprpub/pr/src/pthreads/ptthread.c@6474c204b198 (annotated)

nsprpub/pr/src/pthreads/ptthread.c@6474c204b198 (annotated)

nsprpub/pr/src/pthreads/ptthread.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 /*
 ** File:            ptthread.c
 ** Descritpion:        Implemenation for threds using pthreds
 ** Exports:            ptthread.h
 */
 #if defined(_PR_PTHREADS) || defined(_PR_DCETHREADS)
 #include "prlog.h"
 #include "primpl.h"
 #include "prpdce.h"
 #include <pthread.h>
 #include <unistd.h>
 #include <string.h>
 #include <signal.h>
 #include <dlfcn.h>
 #ifdef SYMBIAN
 /* In Open C sched_get_priority_min/max do not work properly, so we undefine
  * _POSIX_THREAD_PRIORITY_SCHEDULING here.
  */
 #undef _POSIX_THREAD_PRIORITY_SCHEDULING
 #endif
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
 #undef _POSIX_THREAD_PRIORITY_SCHEDULING
 #include <sys/resource.h>
 #ifndef HAVE_GETTID
 #define gettid() (syscall(SYS_gettid))
 #endif
 #endif
 /*
  * Record whether or not we have the privilege to set the scheduling
  * policy and priority of threads.  0 means that privilege is available.
  * EPERM means that privilege is not available.
  */
 static PRIntn pt_schedpriv = 0;
 extern PRLock *_pr_sleeplock;
 static struct _PT_Bookeeping
 {
     PRLock *ml;                 /* a lock to protect ourselves */
     PRCondVar *cv;              /* used to signal global things */
     PRInt32 system, user;       /* a count of the two different types */
     PRUintn this_many;          /* number of threads allowed for exit */
     pthread_key_t key;          /* thread private data key */
     PRBool keyCreated;          /* whether 'key' should be deleted */
     PRThread *first, *last;     /* list of threads we know about */
 #if defined(_PR_DCETHREADS) || defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
     PRInt32 minPrio, maxPrio;   /* range of scheduling priorities */
 #endif
 } pt_book = {0};
 static void _pt_thread_death(void *arg);
 static void _pt_thread_death_internal(void *arg, PRBool callDestructors);
 static void init_pthread_gc_support(void);
 #if defined(_PR_DCETHREADS) || defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
 static PRIntn pt_PriorityMap(PRThreadPriority pri)
 {
 #ifdef NTO
     /* This priority algorithm causes lots of problems on Neutrino
      * for now I have just hard coded everything to run at priority 10
      * until I can come up with a new algorithm.
      *     Jerry.Kirk@Nexwarecorp.com
      */
     return 10;
 #else
     return pt_book.minPrio +
 	    pri * (pt_book.maxPrio - pt_book.minPrio) / PR_PRIORITY_LAST;
 #endif
 }
 #elif defined(_PR_NICE_PRIORITY_SCHEDULING)
 /*
  * This functions maps higher priorities to lower nice values relative to the
  * nice value specified in the |nice| parameter. The corresponding relative
  * adjustments are:
  *
  * PR_PRIORITY_LOW    +1
  * PR_PRIORITY_NORMAL  0
  * PR_PRIORITY_HIGH   -1
  * PR_PRIORITY_URGENT -2
  */
 static int pt_RelativePriority(int nice, PRThreadPriority pri)
 {
     return nice + (1 - pri);
 }
 #endif
 /*
 ** Initialize a stack for a native pthread thread
 */
 static void _PR_InitializeStack(PRThreadStack *ts)
 {
     if( ts && (ts->stackTop == 0) ) {
         ts->allocBase = (char *) &ts;
         ts->allocSize = ts->stackSize;
         /*
         ** Setup stackTop and stackBottom values.
         */
 #ifdef HAVE_STACK_GROWING_UP
         ts->stackBottom = ts->allocBase + ts->stackSize;
         ts->stackTop = ts->allocBase;
 #else
         ts->stackTop    = ts->allocBase;
         ts->stackBottom = ts->allocBase - ts->stackSize;
 #endif
     }
 }
 static void *_pt_root(void *arg)
 {
     PRIntn rv;
     PRThread *thred = (PRThread*)arg;
     PRBool detached = (thred->state & PT_THREAD_DETACHED) ? PR_TRUE : PR_FALSE;
     pthread_t id = pthread_self();
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
     pid_t tid;
 #endif
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
     /*
      * We need to know the kernel thread ID of each thread in order to
      * set its nice value hence we do it here instead of at creation time.
      */
     tid = gettid();
     errno = 0;
     rv = getpriority(PRIO_PROCESS, 0);
     /* If we cannot read the main thread's nice value don't try to change the
      * new thread's nice value. */
     if (errno == 0) {
         setpriority(PRIO_PROCESS, tid,
                     pt_RelativePriority(rv, thred->priority));
     }
 #endif
     /*
     ** DCE Threads can't detach during creation, so do it late.
     ** I would like to do it only here, but that doesn't seem
     ** to work.
     */
 #if defined(_PR_DCETHREADS)
     if (detached)
     {
         /* pthread_detach() modifies its argument, so we must pass a copy */
         pthread_t self = id;
         rv = pthread_detach(&self);
         PR_ASSERT(0 == rv);
     }
 #endif /* defined(_PR_DCETHREADS) */
     /* Set up the thread stack information */
     _PR_InitializeStack(thred->stack);
     /*
      * Set within the current thread the pointer to our object.
      * This object will be deleted when the thread termintates,
      * whether in a join or detached (see _PR_InitThreads()).
      */
     rv = pthread_setspecific(pt_book.key, thred);
     PR_ASSERT(0 == rv);
     /* make the thread visible to the rest of the runtime */
     PR_Lock(pt_book.ml);
     /*
      * Both the parent thread and this new thread set thred->id.
      * The new thread must ensure that thred->id is set before
      * it executes its startFunc.  The parent thread must ensure
      * that thred->id is set before PR_CreateThread() returns.
      * Both threads set thred->id while holding pt_book.ml and
      * use thred->idSet to ensure thred->id is written only once.
      */
     if (!thred->idSet)
     {
         thred->id = id;
         thred->idSet = PR_TRUE;
     }
     else
     {
         PR_ASSERT(pthread_equal(thred->id, id));
     }
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
     thred->tid = tid;
     PR_NotifyAllCondVar(pt_book.cv);
 #endif
     /* If this is a GCABLE thread, set its state appropriately */
     if (thred->suspend & PT_THREAD_SETGCABLE)
 	    thred->state |= PT_THREAD_GCABLE;
     thred->suspend = 0;
     thred->prev = pt_book.last;
     if (pt_book.last)
         pt_book.last->next = thred;
     else
         pt_book.first = thred;
     thred->next = NULL;
     pt_book.last = thred;
     PR_Unlock(pt_book.ml);
     thred->startFunc(thred->arg);  /* make visible to the client */
     /* unhook the thread from the runtime */
     PR_Lock(pt_book.ml);
     /*
      * At this moment, PR_CreateThread() may not have set thred->id yet.
      * It is safe for a detached thread to free thred only after
      * PR_CreateThread() has accessed thred->id and thred->idSet.
      */
     if (detached)
     {
         while (!thred->okToDelete)
             PR_WaitCondVar(pt_book.cv, PR_INTERVAL_NO_TIMEOUT);
     }
     if (thred->state & PT_THREAD_SYSTEM)
         pt_book.system -= 1;
     else if (--pt_book.user == pt_book.this_many)
         PR_NotifyAllCondVar(pt_book.cv);
     if (NULL == thred->prev)
         pt_book.first = thred->next;
     else
         thred->prev->next = thred->next;
     if (NULL == thred->next)
         pt_book.last = thred->prev;
     else
         thred->next->prev = thred->prev;
     PR_Unlock(pt_book.ml);
     /*
     * Here we set the pthread's backpointer to the PRThread to NULL.
     * Otherwise the destructor would get called eagerly as the thread
     * returns to the pthread runtime. The joining thread would them be
     * the proud possessor of a dangling reference. However, this is the
     * last chance to delete the object if the thread is detached, so
     * just let the destructor do the work.
     */
     if (PR_FALSE == detached)
     {
         /* Call TPD destructors on this thread. */
         _PR_DestroyThreadPrivate(thred);
         rv = pthread_setspecific(pt_book.key, NULL);
         PR_ASSERT(0 == rv);
     }
     return NULL;
 }  /* _pt_root */
 static PRThread* pt_AttachThread(void)
 {
     PRThread *thred = NULL;
     /*
      * NSPR must have been initialized when PR_AttachThread is called.
      * We cannot have PR_AttachThread call implicit initialization
      * because if multiple threads call PR_AttachThread simultaneously,
      * NSPR may be initialized more than once.
      * We can't call any function that calls PR_GetCurrentThread()
      * either (e.g., PR_SetError()) as that will result in infinite
      * recursion.
      */
     if (!_pr_initialized) return NULL;
     /* PR_NEWZAP must not call PR_GetCurrentThread() */
     thred = PR_NEWZAP(PRThread);
     if (NULL != thred)
     {
         int rv;
         thred->priority = PR_PRIORITY_NORMAL;
         thred->id = pthread_self();
         thred->idSet = PR_TRUE;
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
         thred->tid = gettid();
 #endif
         rv = pthread_setspecific(pt_book.key, thred);
         PR_ASSERT(0 == rv);
         thred->state = PT_THREAD_GLOBAL | PT_THREAD_FOREIGN;
         PR_Lock(pt_book.ml);
         /* then put it into the list */
         thred->prev = pt_book.last;
         if (pt_book.last)
             pt_book.last->next = thred;
         else
             pt_book.first = thred;
         thred->next = NULL;
         pt_book.last = thred;
         PR_Unlock(pt_book.ml);
     }
     return thred;  /* may be NULL */
 }  /* pt_AttachThread */
 static PRThread* _PR_CreateThread(
     PRThreadType type, void (*start)(void *arg),
     void *arg, PRThreadPriority priority, PRThreadScope scope,
     PRThreadState state, PRUint32 stackSize, PRBool isGCAble)
 {
     int rv;
     PRThread *thred;
     pthread_attr_t tattr;
     if (!_pr_initialized) _PR_ImplicitInitialization();
     if ((PRIntn)PR_PRIORITY_FIRST > (PRIntn)priority)
         priority = PR_PRIORITY_FIRST;
     else if ((PRIntn)PR_PRIORITY_LAST < (PRIntn)priority)
         priority = PR_PRIORITY_LAST;
     rv = _PT_PTHREAD_ATTR_INIT(&tattr);
     PR_ASSERT(0 == rv);
     if (EPERM != pt_schedpriv)
     {
 #if !defined(_PR_DCETHREADS) && defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
         struct sched_param schedule;
 #endif
 #if defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
         rv = pthread_attr_setinheritsched(&tattr, PTHREAD_EXPLICIT_SCHED);
         PR_ASSERT(0 == rv);
 #endif
         /* Use the default scheduling policy */
 #if defined(_PR_DCETHREADS)
         rv = pthread_attr_setprio(&tattr, pt_PriorityMap(priority));
         PR_ASSERT(0 == rv);
 #elif defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
         rv = pthread_attr_getschedparam(&tattr, &schedule);
         PR_ASSERT(0 == rv);
         schedule.sched_priority = pt_PriorityMap(priority);
         rv = pthread_attr_setschedparam(&tattr, &schedule);
         PR_ASSERT(0 == rv);
 #ifdef NTO
         rv = pthread_attr_setschedpolicy(&tattr, SCHED_RR); /* Round Robin */
         PR_ASSERT(0 == rv);
 #endif
 #endif /* !defined(_PR_DCETHREADS) */
     }
     /*
      * DCE threads can't set detach state before creating the thread.
      * AIX can't set detach late. Why can't we all just get along?
      */
 #if !defined(_PR_DCETHREADS)
     rv = pthread_attr_setdetachstate(&tattr,
         ((PR_JOINABLE_THREAD == state) ?
             PTHREAD_CREATE_JOINABLE : PTHREAD_CREATE_DETACHED));
     PR_ASSERT(0 == rv);
 #endif /* !defined(_PR_DCETHREADS) */
     /*
      * If stackSize is 0, we use the default pthread stack size.
      */
     if (stackSize)
     {
 #ifdef _MD_MINIMUM_STACK_SIZE
         if (stackSize < _MD_MINIMUM_STACK_SIZE)
             stackSize = _MD_MINIMUM_STACK_SIZE;
 #endif
         rv = pthread_attr_setstacksize(&tattr, stackSize);
         PR_ASSERT(0 == rv);
     }
     thred = PR_NEWZAP(PRThread);
     if (NULL == thred)
     {
         PR_SetError(PR_OUT_OF_MEMORY_ERROR, errno);
         goto done;
     }
     else
     {
         pthread_t id;
         thred->arg = arg;
         thred->startFunc = start;
         thred->priority = priority;
         if (PR_UNJOINABLE_THREAD == state)
             thred->state |= PT_THREAD_DETACHED;
         if (PR_LOCAL_THREAD == scope)
         	scope = PR_GLOBAL_THREAD;
         if (PR_GLOBAL_BOUND_THREAD == scope) {
 #if defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
     		rv = pthread_attr_setscope(&tattr, PTHREAD_SCOPE_SYSTEM);
 			if (rv) {
 				/*
 				 * system scope not supported
 				 */
         		scope = PR_GLOBAL_THREAD;
 				/*
 				 * reset scope
 				 */
     			rv = pthread_attr_setscope(&tattr, PTHREAD_SCOPE_PROCESS);
     			PR_ASSERT(0 == rv);
 			}
 #endif
 		}
         if (PR_GLOBAL_THREAD == scope)
             thred->state |= PT_THREAD_GLOBAL;
         else if (PR_GLOBAL_BOUND_THREAD == scope)
             thred->state |= (PT_THREAD_GLOBAL | PT_THREAD_BOUND);
 		else	/* force it global */
             thred->state |= PT_THREAD_GLOBAL;
         if (PR_SYSTEM_THREAD == type)
             thred->state |= PT_THREAD_SYSTEM;
         thred->suspend =(isGCAble) ? PT_THREAD_SETGCABLE : 0;
         thred->stack = PR_NEWZAP(PRThreadStack);
         if (thred->stack == NULL) {
             PRIntn oserr = errno;
             PR_Free(thred);  /* all that work ... poof! */
             PR_SetError(PR_OUT_OF_MEMORY_ERROR, oserr);
             thred = NULL;  /* and for what? */
             goto done;
         }
         thred->stack->stackSize = stackSize;
         thred->stack->thr = thred;
 #ifdef PT_NO_SIGTIMEDWAIT
         pthread_mutex_init(&thred->suspendResumeMutex,NULL);
         pthread_cond_init(&thred->suspendResumeCV,NULL);
 #endif
         /* make the thread counted to the rest of the runtime */
         PR_Lock(pt_book.ml);
         if (PR_SYSTEM_THREAD == type)
             pt_book.system += 1;
         else pt_book.user += 1;
         PR_Unlock(pt_book.ml);
         /*
          * We pass a pointer to a local copy (instead of thred->id)
          * to pthread_create() because who knows what wacky things
          * pthread_create() may be doing to its argument.
          */
         rv = _PT_PTHREAD_CREATE(&id, tattr, _pt_root, thred);
 #if !defined(_PR_DCETHREADS)
         if (EPERM == rv)
         {
 #if defined(IRIX)
         	if (PR_GLOBAL_BOUND_THREAD == scope) {
 				/*
 				 * SCOPE_SYSTEM requires appropriate privilege
 				 * reset to process scope and try again
 				 */
     			rv = pthread_attr_setscope(&tattr, PTHREAD_SCOPE_PROCESS);
     			PR_ASSERT(0 == rv);
             	thred->state &= ~PT_THREAD_BOUND;
 			}
 #else
             /* Remember that we don't have thread scheduling privilege. */
             pt_schedpriv = EPERM;
             PR_LOG(_pr_thread_lm, PR_LOG_MIN,
                 ("_PR_CreateThread: no thread scheduling privilege"));
             /* Try creating the thread again without setting priority. */
 #if defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
             rv = pthread_attr_setinheritsched(&tattr, PTHREAD_INHERIT_SCHED);
             PR_ASSERT(0 == rv);
 #endif
 #endif	/* IRIX */
             rv = _PT_PTHREAD_CREATE(&id, tattr, _pt_root, thred);
         }
 #endif
         if (0 != rv)
         {
 #if defined(_PR_DCETHREADS)
             PRIntn oserr = errno;
 #else
             PRIntn oserr = rv;
 #endif
             PR_Lock(pt_book.ml);
             if (thred->state & PT_THREAD_SYSTEM)
                 pt_book.system -= 1;
             else if (--pt_book.user == pt_book.this_many)
                 PR_NotifyAllCondVar(pt_book.cv);
             PR_Unlock(pt_book.ml);
             PR_Free(thred->stack);
             PR_Free(thred);  /* all that work ... poof! */
             PR_SetError(PR_INSUFFICIENT_RESOURCES_ERROR, oserr);
             thred = NULL;  /* and for what? */
             goto done;
         }
         PR_Lock(pt_book.ml);
         /*
          * Both the parent thread and this new thread set thred->id.
          * The parent thread must ensure that thred->id is set before
          * PR_CreateThread() returns.  (See comments in _pt_root().)
          */
         if (!thred->idSet)
         {
             thred->id = id;
             thred->idSet = PR_TRUE;
         }
         else
         {
             PR_ASSERT(pthread_equal(thred->id, id));
         }
         /*
          * If the new thread is detached, tell it that PR_CreateThread() has
          * accessed thred->id and thred->idSet so it's ok to delete thred.
          */
         if (PR_UNJOINABLE_THREAD == state)
         {
             thred->okToDelete = PR_TRUE;
             PR_NotifyAllCondVar(pt_book.cv);
         }
         PR_Unlock(pt_book.ml);
     }
 done:
     rv = _PT_PTHREAD_ATTR_DESTROY(&tattr);
     PR_ASSERT(0 == rv);
     return thred;
 }  /* _PR_CreateThread */
 PR_IMPLEMENT(PRThread*) PR_CreateThread(
     PRThreadType type, void (*start)(void *arg), void *arg,
     PRThreadPriority priority, PRThreadScope scope,
     PRThreadState state, PRUint32 stackSize)
 {
     return _PR_CreateThread(
         type, start, arg, priority, scope, state, stackSize, PR_FALSE);
 } /* PR_CreateThread */
 PR_IMPLEMENT(PRThread*) PR_CreateThreadGCAble(
     PRThreadType type, void (*start)(void *arg), void *arg,
     PRThreadPriority priority, PRThreadScope scope,
     PRThreadState state, PRUint32 stackSize)
 {
     return _PR_CreateThread(
         type, start, arg, priority, scope, state, stackSize, PR_TRUE);
 }  /* PR_CreateThreadGCAble */
 PR_IMPLEMENT(void*) GetExecutionEnvironment(PRThread *thred)
 {
     return thred->environment;
 }  /* GetExecutionEnvironment */
 PR_IMPLEMENT(void) SetExecutionEnvironment(PRThread *thred, void *env)
 {
     thred->environment = env;
 }  /* SetExecutionEnvironment */
 PR_IMPLEMENT(PRThread*) PR_AttachThread(
     PRThreadType type, PRThreadPriority priority, PRThreadStack *stack)
 {
     return PR_GetCurrentThread();
 }  /* PR_AttachThread */
 PR_IMPLEMENT(PRStatus) PR_JoinThread(PRThread *thred)
 {
     int rv = -1;
     void *result = NULL;
     PR_ASSERT(thred != NULL);
     if ((0xafafafaf == thred->state)
     || (PT_THREAD_DETACHED == (PT_THREAD_DETACHED & thred->state))
     || (PT_THREAD_FOREIGN == (PT_THREAD_FOREIGN & thred->state)))
     {
         /*
          * This might be a bad address, but if it isn't, the state should
          * either be an unjoinable thread or it's already had the object
          * deleted. However, the client that called join on a detached
          * thread deserves all the rath I can muster....
          */
         PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
         PR_LogPrint(
             "PR_JoinThread: %p not joinable | already smashed\n", thred);
     }
     else
     {
         pthread_t id = thred->id;
         rv = pthread_join(id, &result);
         PR_ASSERT(rv == 0 && result == NULL);
         if (0 == rv)
         {
 #ifdef _PR_DCETHREADS
             rv = pthread_detach(&id);
             PR_ASSERT(0 == rv);
 #endif
             /*
              * PR_FALSE, because the thread already called the TPD
              * destructors before exiting _pt_root.
              */
             _pt_thread_death_internal(thred, PR_FALSE);
         }
         else
         {
             PRErrorCode prerror;
             switch (rv)
             {
                 case EINVAL:  /* not a joinable thread */
                 case ESRCH:   /* no thread with given ID */
                     prerror = PR_INVALID_ARGUMENT_ERROR;
                     break;
                 case EDEADLK: /* a thread joining with itself */
                     prerror = PR_DEADLOCK_ERROR;
                     break;
                 default:
                     prerror = PR_UNKNOWN_ERROR;
                     break;
             }
             PR_SetError(prerror, rv);
         }
     }
     return (0 == rv) ? PR_SUCCESS : PR_FAILURE;
 }  /* PR_JoinThread */
 PR_IMPLEMENT(void) PR_DetachThread(void)
 {
     void *thred;
     int rv;
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL == thred) return;
     _pt_thread_death(thred);
     rv = pthread_setspecific(pt_book.key, NULL);
     PR_ASSERT(0 == rv);
 }  /* PR_DetachThread */
 PR_IMPLEMENT(PRThread*) PR_GetCurrentThread(void)
 {
     void *thred;
     if (!_pr_initialized) _PR_ImplicitInitialization();
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL == thred) thred = pt_AttachThread();
     PR_ASSERT(NULL != thred);
     return (PRThread*)thred;
 }  /* PR_GetCurrentThread */
 PR_IMPLEMENT(PRThreadScope) PR_GetThreadScope(const PRThread *thred)
 {
     return (thred->state & PT_THREAD_BOUND) ?
         PR_GLOBAL_BOUND_THREAD : PR_GLOBAL_THREAD;
 }  /* PR_GetThreadScope() */
 PR_IMPLEMENT(PRThreadType) PR_GetThreadType(const PRThread *thred)
 {
     return (thred->state & PT_THREAD_SYSTEM) ?
         PR_SYSTEM_THREAD : PR_USER_THREAD;
 }
 PR_IMPLEMENT(PRThreadState) PR_GetThreadState(const PRThread *thred)
 {
     return (thred->state & PT_THREAD_DETACHED) ?
         PR_UNJOINABLE_THREAD : PR_JOINABLE_THREAD;
 }  /* PR_GetThreadState */
 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)
 {
     PRIntn rv = -1;
     PR_ASSERT(NULL != thred);
     if ((PRIntn)PR_PRIORITY_FIRST > (PRIntn)newPri)
         newPri = PR_PRIORITY_FIRST;
     else if ((PRIntn)PR_PRIORITY_LAST < (PRIntn)newPri)
         newPri = PR_PRIORITY_LAST;
 #if defined(_PR_DCETHREADS)
     rv = pthread_setprio(thred->id, pt_PriorityMap(newPri));
     /* pthread_setprio returns the old priority */
 #elif defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
     if (EPERM != pt_schedpriv)
     {
         int policy;
         struct sched_param schedule;
         rv = pthread_getschedparam(thred->id, &policy, &schedule);
         if(0 == rv) {
 			schedule.sched_priority = pt_PriorityMap(newPri);
 			rv = pthread_setschedparam(thred->id, policy, &schedule);
 			if (EPERM == rv)
 			{
 				pt_schedpriv = EPERM;
 				PR_LOG(_pr_thread_lm, PR_LOG_MIN,
 					("PR_SetThreadPriority: no thread scheduling privilege"));
 			}
 		}
 		if (rv != 0)
 			rv = -1;
     }
 #elif defined(_PR_NICE_PRIORITY_SCHEDULING)
     PR_Lock(pt_book.ml);
     while (thred->tid == 0)
         PR_WaitCondVar(pt_book.cv, PR_INTERVAL_NO_TIMEOUT);
     PR_Unlock(pt_book.ml);
     errno = 0;
     rv = getpriority(PRIO_PROCESS, 0);
     /* Do not proceed unless we know the main thread's nice value. */
     if (errno == 0) {
         rv = setpriority(PRIO_PROCESS, thred->tid,
                          pt_RelativePriority(rv, newPri));
         if (rv == -1)
         {
             /* We don't set pt_schedpriv to EPERM in case errno == EPERM
              * because adjusting the nice value might be permitted for certain
              * ranges but not for others. */
             PR_LOG(_pr_thread_lm, PR_LOG_MIN,
                 ("PR_SetThreadPriority: setpriority failed with error %d",
                  errno));
         }
     }
 #endif
     thred->priority = newPri;
 }  /* PR_SetThreadPriority */
 PR_IMPLEMENT(PRStatus) PR_Interrupt(PRThread *thred)
 {
     /*
     ** If the target thread indicates that it's waiting,
     ** find the condition and broadcast to it. Broadcast
     ** since we don't know which thread (if there are more
     ** than one). This sounds risky, but clients must
     ** test their invariants when resumed from a wait and
     ** I don't expect very many threads to be waiting on
     ** a single condition and I don't expect interrupt to
     ** be used very often.
     **
     ** I don't know why I thought this would work. Must have
     ** been one of those weaker momements after I'd been
     ** smelling the vapors.
     **
     ** Even with the followng changes it is possible that
     ** the pointer to the condition variable is pointing
     ** at a bogus value. Will the unerlying code detect
     ** that?
     */
     PRCondVar *cv;
     PR_ASSERT(NULL != thred);
     if (NULL == thred) return PR_FAILURE;
     thred->state |= PT_THREAD_ABORTED;
     cv = thred->waiting;
     if ((NULL != cv) && !thred->interrupt_blocked)
     {
         PRIntn rv;
         (void)PR_ATOMIC_INCREMENT(&cv->notify_pending);
         rv = pthread_cond_broadcast(&cv->cv);
         PR_ASSERT(0 == rv);
         if (0 > PR_ATOMIC_DECREMENT(&cv->notify_pending))
             PR_DestroyCondVar(cv);
     }
     return PR_SUCCESS;
 }  /* PR_Interrupt */
 PR_IMPLEMENT(void) PR_ClearInterrupt(void)
 {
     PRThread *me = PR_GetCurrentThread();
     me->state &= ~PT_THREAD_ABORTED;
 }  /* PR_ClearInterrupt */
 PR_IMPLEMENT(void) PR_BlockInterrupt(void)
 {
     PRThread *me = PR_GetCurrentThread();
     _PT_THREAD_BLOCK_INTERRUPT(me);
 }  /* PR_BlockInterrupt */
 PR_IMPLEMENT(void) PR_UnblockInterrupt(void)
 {
     PRThread *me = PR_GetCurrentThread();
     _PT_THREAD_UNBLOCK_INTERRUPT(me);
 }  /* PR_UnblockInterrupt */
 PR_IMPLEMENT(PRStatus) PR_Yield(void)
 {
     static PRBool warning = PR_TRUE;
     if (warning) warning = _PR_Obsolete(
         "PR_Yield()", "PR_Sleep(PR_INTERVAL_NO_WAIT)");
     return PR_Sleep(PR_INTERVAL_NO_WAIT);
 }
 PR_IMPLEMENT(PRStatus) PR_Sleep(PRIntervalTime ticks)
 {
     PRStatus rv = PR_SUCCESS;
     if (!_pr_initialized) _PR_ImplicitInitialization();
     if (PR_INTERVAL_NO_WAIT == ticks)
     {
         _PT_PTHREAD_YIELD();
     }
     else
     {
         PRCondVar *cv;
         PRIntervalTime timein;
         timein = PR_IntervalNow();
         cv = PR_NewCondVar(_pr_sleeplock);
         PR_ASSERT(cv != NULL);
         PR_Lock(_pr_sleeplock);
         do
         {
             PRIntervalTime now = PR_IntervalNow();
             PRIntervalTime delta = now - timein;
             if (delta > ticks) break;
             rv = PR_WaitCondVar(cv, ticks - delta);
         } while (PR_SUCCESS == rv);
         PR_Unlock(_pr_sleeplock);
         PR_DestroyCondVar(cv);
     }
     return rv;
 }  /* PR_Sleep */
 static void _pt_thread_death(void *arg)
 {
     void *thred;
     int rv;
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL == thred)
     {
         /*
          * Have PR_GetCurrentThread return the expected value to the
          * destructors.
          */
         rv = pthread_setspecific(pt_book.key, arg);
         PR_ASSERT(0 == rv);
     }
     /* PR_TRUE for: call destructors */
     _pt_thread_death_internal(arg, PR_TRUE);
     if (NULL == thred)
     {
         rv = pthread_setspecific(pt_book.key, NULL);
         PR_ASSERT(0 == rv);
     }
 }
 static void _pt_thread_death_internal(void *arg, PRBool callDestructors)
 {
     PRThread *thred = (PRThread*)arg;
     if (thred->state & (PT_THREAD_FOREIGN|PT_THREAD_PRIMORD))
     {
         PR_Lock(pt_book.ml);
         if (NULL == thred->prev)
             pt_book.first = thred->next;
         else
             thred->prev->next = thred->next;
         if (NULL == thred->next)
             pt_book.last = thred->prev;
         else
             thred->next->prev = thred->prev;
         PR_Unlock(pt_book.ml);
     }
     if (callDestructors)
         _PR_DestroyThreadPrivate(thred);
     PR_Free(thred->privateData);
     if (NULL != thred->errorString)
         PR_Free(thred->errorString);
     if (NULL != thred->name)
         PR_Free(thred->name);
     PR_Free(thred->stack);
     if (NULL != thred->syspoll_list)
         PR_Free(thred->syspoll_list);
 #if defined(_PR_POLL_WITH_SELECT)
     if (NULL != thred->selectfd_list)
         PR_Free(thred->selectfd_list);
 #endif
 #if defined(DEBUG)
     memset(thred, 0xaf, sizeof(PRThread));
 #endif /* defined(DEBUG) */
     PR_Free(thred);
 }  /* _pt_thread_death */
 void _PR_InitThreads(
     PRThreadType type, PRThreadPriority priority, PRUintn maxPTDs)
 {
     int rv;
     PRThread *thred;
     PR_ASSERT(priority == PR_PRIORITY_NORMAL);
 #ifdef _PR_NEED_PTHREAD_INIT
     /*
      * On BSD/OS (3.1 and 4.0), the pthread subsystem is lazily
      * initialized, but pthread_self() fails to initialize
      * pthreads and hence returns a null thread ID if invoked
      * by the primordial thread before any other pthread call.
      * So we explicitly initialize pthreads here.
      */
     pthread_init();
 #endif
 #if defined(_PR_DCETHREADS) || defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
 #if defined(FREEBSD)
     {
     pthread_attr_t attr;
     int policy;
     /* get the min and max priorities of the default policy */
     pthread_attr_init(&attr);
     pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED);
     pthread_attr_getschedpolicy(&attr, &policy);
     pt_book.minPrio = sched_get_priority_min(policy);
     PR_ASSERT(-1 != pt_book.minPrio);
     pt_book.maxPrio = sched_get_priority_max(policy);
     PR_ASSERT(-1 != pt_book.maxPrio);
     pthread_attr_destroy(&attr);
     }
 #else
     /*
     ** These might be function evaluations
     */
     pt_book.minPrio = PT_PRIO_MIN;
     pt_book.maxPrio = PT_PRIO_MAX;
 #endif
 #endif
     PR_ASSERT(NULL == pt_book.ml);
     pt_book.ml = PR_NewLock();
     PR_ASSERT(NULL != pt_book.ml);
     pt_book.cv = PR_NewCondVar(pt_book.ml);
     PR_ASSERT(NULL != pt_book.cv);
     thred = PR_NEWZAP(PRThread);
     PR_ASSERT(NULL != thred);
     thred->arg = NULL;
     thred->startFunc = NULL;
     thred->priority = priority;
     thred->id = pthread_self();
     thred->idSet = PR_TRUE;
 #ifdef _PR_NICE_PRIORITY_SCHEDULING
     thred->tid = gettid();
 #endif
     thred->state = (PT_THREAD_DETACHED | PT_THREAD_PRIMORD);
     if (PR_SYSTEM_THREAD == type)
     {
         thred->state |= PT_THREAD_SYSTEM;
         pt_book.system += 1;
 	    pt_book.this_many = 0;
     }
     else
     {
 	    pt_book.user += 1;
 	    pt_book.this_many = 1;
     }
     thred->next = thred->prev = NULL;
     pt_book.first = pt_book.last = thred;
     thred->stack = PR_NEWZAP(PRThreadStack);
     PR_ASSERT(thred->stack != NULL);
     thred->stack->stackSize = 0;
     thred->stack->thr = thred;
 	_PR_InitializeStack(thred->stack);
     /*
      * Create a key for our use to store a backpointer in the pthread
      * to our PRThread object. This object gets deleted when the thread
      * returns from its root in the case of a detached thread. Other
      * threads delete the objects in Join.
      *
      * NB: The destructor logic seems to have a bug so it isn't used.
      * NBB: Oh really? I'm going to give it a spin - AOF 19 June 1998.
      * More info - the problem is that pthreads calls the destructor
      * eagerly as the thread returns from its root, rather than lazily
      * after the thread is joined. Therefore, threads that are joining
      * and holding PRThread references are actually holding pointers to
      * nothing.
      */
     rv = _PT_PTHREAD_KEY_CREATE(&pt_book.key, _pt_thread_death);
     if (0 != rv)
         PR_Assert("0 == rv", __FILE__, __LINE__);
     pt_book.keyCreated = PR_TRUE;
     rv = pthread_setspecific(pt_book.key, thred);
     PR_ASSERT(0 == rv);
 }  /* _PR_InitThreads */
 #ifdef __GNUC__
 /*
  * GCC supports the constructor and destructor attributes as of
  * version 2.5.
  */
 static void _PR_Fini(void) __attribute__ ((destructor));
 #elif defined(__SUNPRO_C)
 /*
  * Sun Studio compiler
  */
 #pragma fini(_PR_Fini)
 static void _PR_Fini(void);
 #elif defined(HPUX)
 /*
  * Current versions of HP C compiler define __HP_cc.
  * HP C compiler A.11.01.20 doesn't define __HP_cc.
  */
 #if defined(__ia64) || defined(_LP64)
 #pragma FINI "_PR_Fini"
 static void _PR_Fini(void);
 #else
 /*
  * Only HP-UX 10.x style initializers are supported in 32-bit links.
  * Need to use the +I PR_HPUX10xInit linker option.
  */
 #include <dl.h>
 static void _PR_Fini(void);
 void PR_HPUX10xInit(shl_t handle, int loading)
 {
     /*
      * This function is called when a shared library is loaded as well
      * as when the shared library is unloaded.  Note that it may not
      * be called when the user's program terminates.
      *
      * handle is the shl_load API handle for the shared library being
      * initialized.
      *
      * loading is non-zero at startup and zero at termination.
      */
     if (loading) {
 	/* ... do some initializations ... */
     } else {
 	_PR_Fini();
     }
 }
 #endif
 #elif defined(AIX)
 /* Need to use the -binitfini::_PR_Fini linker option. */
 #endif
 void _PR_Fini(void)
 {
     void *thred;
     int rv;
     if (!_pr_initialized) {
         /* Either NSPR was never successfully initialized or
          * PR_Cleanup has been called already. */
         if (pt_book.keyCreated)
         {
             rv = pthread_key_delete(pt_book.key);
             PR_ASSERT(0 == rv);
             pt_book.keyCreated = PR_FALSE;
         }
         return;
     }
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL != thred)
     {
         /*
          * PR_FALSE, because it is unsafe to call back to the
          * thread private data destructors at final cleanup.
          */
         _pt_thread_death_internal(thred, PR_FALSE);
         rv = pthread_setspecific(pt_book.key, NULL);
         PR_ASSERT(0 == rv);
     }
     rv = pthread_key_delete(pt_book.key);
     PR_ASSERT(0 == rv);
     pt_book.keyCreated = PR_FALSE;
     /* TODO: free other resources used by NSPR */
     /* _pr_initialized = PR_FALSE; */
 }  /* _PR_Fini */
 PR_IMPLEMENT(PRStatus) PR_Cleanup(void)
 {
     PRThread *me = PR_GetCurrentThread();
     int rv;
     PR_LOG(_pr_thread_lm, PR_LOG_MIN, ("PR_Cleanup: shutting down NSPR"));
     PR_ASSERT(me->state & PT_THREAD_PRIMORD);
     if (me->state & PT_THREAD_PRIMORD)
     {
         PR_Lock(pt_book.ml);
         while (pt_book.user > pt_book.this_many)
             PR_WaitCondVar(pt_book.cv, PR_INTERVAL_NO_TIMEOUT);
         if (me->state & PT_THREAD_SYSTEM)
             pt_book.system -= 1;
         else
             pt_book.user -= 1;
         PR_Unlock(pt_book.ml);
         _PR_MD_EARLY_CLEANUP();
         _PR_CleanupMW();
         _PR_CleanupTime();
         _PR_CleanupDtoa();
         _PR_CleanupCallOnce();
         _PR_ShutdownLinker();
         _PR_LogCleanup();
         _PR_CleanupNet();
         /* Close all the fd's before calling _PR_CleanupIO */
         _PR_CleanupIO();
         _PR_CleanupCMon();
         _pt_thread_death(me);
         rv = pthread_setspecific(pt_book.key, NULL);
         PR_ASSERT(0 == rv);
         /*
          * I am not sure if it's safe to delete the cv and lock here,
          * since there may still be "system" threads around. If this
          * call isn't immediately prior to exiting, then there's a
          * problem.
          */
         if (0 == pt_book.system)
         {
             PR_DestroyCondVar(pt_book.cv); pt_book.cv = NULL;
             PR_DestroyLock(pt_book.ml); pt_book.ml = NULL;
         }
         PR_DestroyLock(_pr_sleeplock);
         _pr_sleeplock = NULL;
         _PR_CleanupLayerCache();
         _PR_CleanupEnv();
 #ifdef _PR_ZONE_ALLOCATOR
         _PR_DestroyZones();
 #endif
         _pr_initialized = PR_FALSE;
         return PR_SUCCESS;
     }
     return PR_FAILURE;
 }  /* PR_Cleanup */
 PR_IMPLEMENT(void) PR_ProcessExit(PRIntn status)
 {
     _exit(status);
 }
 PR_IMPLEMENT(PRUint32) PR_GetThreadID(PRThread *thred)
 {
 #if defined(_PR_DCETHREADS)
     return (PRUint32)&thred->id;  /* this is really a sham! */
 #else
     return (PRUint32)thred->id;  /* and I don't know what they will do with it */
 #endif
 }
 /*
  * $$$
  * The following two thread-to-processor affinity functions are not
  * yet implemented for pthreads.  By the way, these functions should return
  * PRStatus rather than PRInt32 to indicate the success/failure status.
  * $$$
  */
 PR_IMPLEMENT(PRInt32) PR_GetThreadAffinityMask(PRThread *thread, PRUint32 *mask)
 {
     return 0;  /* not implemented */
 }
 PR_IMPLEMENT(PRInt32) PR_SetThreadAffinityMask(PRThread *thread, PRUint32 mask )
 {
     return 0;  /* not implemented */
 }
 PR_IMPLEMENT(void)
 PR_SetThreadDumpProc(PRThread* thread, PRThreadDumpProc dump, void *arg)
 {
     thread->dump = dump;
     thread->dumpArg = arg;
 }
 /*
  * Garbage collection support follows.
  */
 #if defined(_PR_DCETHREADS)
 /*
  * statics for Garbage Collection support.  We don't need to protect these
  * signal masks since the garbage collector itself is protected by a lock
  * and multiple threads will not be garbage collecting at the same time.
  */
 static sigset_t javagc_vtalarm_sigmask;
 static sigset_t javagc_intsoff_sigmask;
 #else /* defined(_PR_DCETHREADS) */
 /* a bogus signal mask for forcing a timed wait */
 /* Not so bogus in AIX as we really do a sigwait */
 static sigset_t sigwait_set;
 static struct timespec onemillisec = {0, 1000000L};
 #ifndef PT_NO_SIGTIMEDWAIT
 static struct timespec hundredmillisec = {0, 100000000L};
 #endif
 static void suspend_signal_handler(PRIntn sig);
 #ifdef PT_NO_SIGTIMEDWAIT
 static void null_signal_handler(PRIntn sig);
 #endif
 #endif /* defined(_PR_DCETHREADS) */
 /*
  * Linux pthreads use SIGUSR1 and SIGUSR2 internally, which
  * conflict with the use of these two signals in our GC support.
  * So we don't know how to support GC on Linux pthreads.
  */
 static void init_pthread_gc_support(void)
 {
 #ifndef SYMBIAN
     PRIntn rv;
 #if defined(_PR_DCETHREADS)
 	rv = sigemptyset(&javagc_vtalarm_sigmask);
     PR_ASSERT(0 == rv);
 	rv = sigaddset(&javagc_vtalarm_sigmask, SIGVTALRM);
     PR_ASSERT(0 == rv);
 #else  /* defined(_PR_DCETHREADS) */
 	{
 	    struct sigaction sigact_usr2;
 	    sigact_usr2.sa_handler = suspend_signal_handler;
 	    sigact_usr2.sa_flags = SA_RESTART;
 	    sigemptyset (&sigact_usr2.sa_mask);
         rv = sigaction (SIGUSR2, &sigact_usr2, NULL);
         PR_ASSERT(0 == rv);
         sigemptyset (&sigwait_set);
 #if defined(PT_NO_SIGTIMEDWAIT)
         sigaddset (&sigwait_set, SIGUSR1);
 #else
         sigaddset (&sigwait_set, SIGUSR2);
 #endif  /* defined(PT_NO_SIGTIMEDWAIT) */
 	}
 #if defined(PT_NO_SIGTIMEDWAIT)
 	{
 	    struct sigaction sigact_null;
 	    sigact_null.sa_handler = null_signal_handler;
 	    sigact_null.sa_flags = SA_RESTART;
 	    sigemptyset (&sigact_null.sa_mask);
         rv = sigaction (SIGUSR1, &sigact_null, NULL);
 	    PR_ASSERT(0 ==rv);
     }
 #endif  /* defined(PT_NO_SIGTIMEDWAIT) */
 #endif /* defined(_PR_DCETHREADS) */
 #endif /* SYMBIAN */
 }
 PR_IMPLEMENT(void) PR_SetThreadGCAble(void)
 {
     PR_Lock(pt_book.ml);
 	PR_GetCurrentThread()->state |= PT_THREAD_GCABLE;
     PR_Unlock(pt_book.ml);
 }
 PR_IMPLEMENT(void) PR_ClearThreadGCAble(void)
 {
     PR_Lock(pt_book.ml);
 	PR_GetCurrentThread()->state &= (~PT_THREAD_GCABLE);
     PR_Unlock(pt_book.ml);
 }
 #if defined(DEBUG)
 static PRBool suspendAllOn = PR_FALSE;
 #endif
 static PRBool suspendAllSuspended = PR_FALSE;
 PR_IMPLEMENT(PRStatus) PR_EnumerateThreads(PREnumerator func, void *arg)
 {
     PRIntn count = 0;
     PRStatus rv = PR_SUCCESS;
     PRThread* thred = pt_book.first;
 #if defined(DEBUG) || defined(FORCE_PR_ASSERT)
 #if !defined(_PR_DCETHREADS)
     PRThread *me = PR_GetCurrentThread();
 #endif
 #endif
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_EnumerateThreads\n"));
     /*
      * $$$
      * Need to suspend all threads other than me before doing this.
      * This is really a gross and disgusting thing to do. The only
      * good thing is that since all other threads are suspended, holding
      * the lock during a callback seems like child's play.
      * $$$
      */
     PR_ASSERT(suspendAllOn);
     while (thred != NULL)
     {
         /* Steve Morse, 4-23-97: Note that we can't walk a queue by taking
          * qp->next after applying the function "func".  In particular, "func"
          * might remove the thread from the queue and put it into another one in
          * which case qp->next no longer points to the next entry in the original
          * queue.
          *
          * To get around this problem, we save qp->next in qp_next before applying
          * "func" and use that saved value as the next value after applying "func".
          */
         PRThread* next = thred->next;
         if (_PT_IS_GCABLE_THREAD(thred))
         {
 #if !defined(_PR_DCETHREADS)
             PR_ASSERT((thred == me) || (thred->suspend & PT_THREAD_SUSPENDED));
 #endif
             PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
                    ("In PR_EnumerateThreads callback thread %p thid = %X\n",
                     thred, thred->id));
             rv = func(thred, count++, arg);
             if (rv != PR_SUCCESS)
                 return rv;
         }
         thred = next;
     }
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("End PR_EnumerateThreads count = %d \n", count));
     return rv;
 }  /* PR_EnumerateThreads */
 /*
  * PR_SuspendAll and PR_ResumeAll are called during garbage collection.  The strategy
  * we use is to send a SIGUSR2 signal to every gc able thread that we intend to suspend.
  * The signal handler will record the stack pointer and will block until resumed by
  * the resume call.  Since the signal handler is the last routine called for the
  * suspended thread, the stack pointer will also serve as a place where all the
  * registers have been saved on the stack for the previously executing routines.
  *
  * Through global variables, we also make sure that PR_Suspend and PR_Resume does not
  * proceed until the thread is suspended or resumed.
  */
 #if !defined(_PR_DCETHREADS)
 /*
  * In the signal handler, we can not use condition variable notify or wait.
  * This does not work consistently across all pthread platforms.  We also can not
  * use locking since that does not seem to work reliably across platforms.
  * Only thing we can do is yielding while testing for a global condition
  * to change.  This does work on pthread supported platforms.  We may have
  * to play with priortities if there are any problems detected.
  */
  /*
   * In AIX, you cannot use ANY pthread calls in the signal handler except perhaps
   * pthread_yield. But that is horribly inefficient. Hence we use only sigwait, no
   * sigtimedwait is available. We need to use another user signal, SIGUSR1. Actually
   * SIGUSR1 is also used by exec in Java. So our usage here breaks the exec in Java,
   * for AIX. You cannot use pthread_cond_wait or pthread_delay_np in the signal
   * handler as all synchronization mechanisms just break down.
   */
 #if defined(PT_NO_SIGTIMEDWAIT)
 static void null_signal_handler(PRIntn sig)
 {
 	return;
 }
 #endif
 static void suspend_signal_handler(PRIntn sig)
 {
 	PRThread *me = PR_GetCurrentThread();
 	PR_ASSERT(me != NULL);
 	PR_ASSERT(_PT_IS_GCABLE_THREAD(me));
 	PR_ASSERT((me->suspend & PT_THREAD_SUSPENDED) == 0);
 	PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
         ("Begin suspend_signal_handler thred %p thread id = %X\n",
 		me, me->id));
 	/*
 	 * save stack pointer
 	 */
 	me->sp = &me;
 	/*
 	   At this point, the thread's stack pointer has been saved,
 	   And it is going to enter a wait loop until it is resumed.
 	   So it is _really_ suspended
 	*/
 	me->suspend |= PT_THREAD_SUSPENDED;
 	/*
 	 * now, block current thread
 	 */
 #if defined(PT_NO_SIGTIMEDWAIT)
 	pthread_cond_signal(&me->suspendResumeCV);
 	while (me->suspend & PT_THREAD_SUSPENDED)
 	{
 #if !defined(FREEBSD) && !defined(NETBSD) && !defined(OPENBSD) \
     && !defined(BSDI) && !defined(UNIXWARE) \
     && !defined(DARWIN) && !defined(RISCOS) \
     && !defined(SYMBIAN) /*XXX*/
         PRIntn rv;
 	    sigwait(&sigwait_set, &rv);
 #endif
 	}
 	me->suspend |= PT_THREAD_RESUMED;
 	pthread_cond_signal(&me->suspendResumeCV);
 #else /* defined(PT_NO_SIGTIMEDWAIT) */
 	while (me->suspend & PT_THREAD_SUSPENDED)
 	{
 		PRIntn rv = sigtimedwait(&sigwait_set, NULL, &hundredmillisec);
     	PR_ASSERT(-1 == rv);
 	}
 	me->suspend |= PT_THREAD_RESUMED;
 #endif
     /*
      * At this point, thread has been resumed, so set a global condition.
      * The ResumeAll needs to know that this has really been resumed.
      * So the signal handler sets a flag which PR_ResumeAll will reset.
      * The PR_ResumeAll must reset this flag ...
      */
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
         ("End suspend_signal_handler thred = %p tid = %X\n", me, me->id));
 }  /* suspend_signal_handler */
 static void pt_SuspendSet(PRThread *thred)
 {
     PRIntn rv;
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("pt_SuspendSet thred %p thread id = %X\n", thred, thred->id));
     /*
      * Check the thread state and signal the thread to suspend
      */
     PR_ASSERT((thred->suspend & PT_THREAD_SUSPENDED) == 0);
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("doing pthread_kill in pt_SuspendSet thred %p tid = %X\n",
 	   thred, thred->id));
 #if defined(SYMBIAN)
     /* All signal group functions are not implemented in Symbian OS */
     rv = 0;
 #else
     rv = pthread_kill (thred->id, SIGUSR2);
 #endif
     PR_ASSERT(0 == rv);
 }
 static void pt_SuspendTest(PRThread *thred)
 {
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("Begin pt_SuspendTest thred %p thread id = %X\n", thred, thred->id));
     /*
      * Wait for the thread to be really suspended. This happens when the
      * suspend signal handler stores the stack pointer and sets the state
      * to suspended.
      */
 #if defined(PT_NO_SIGTIMEDWAIT)
     pthread_mutex_lock(&thred->suspendResumeMutex);
     while ((thred->suspend & PT_THREAD_SUSPENDED) == 0)
     {
 	    pthread_cond_timedwait(
 	        &thred->suspendResumeCV, &thred->suspendResumeMutex, &onemillisec);
 	}
 	pthread_mutex_unlock(&thred->suspendResumeMutex);
 #else
     while ((thred->suspend & PT_THREAD_SUSPENDED) == 0)
     {
 		PRIntn rv = sigtimedwait(&sigwait_set, NULL, &onemillisec);
     	PR_ASSERT(-1 == rv);
 	}
 #endif
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
         ("End pt_SuspendTest thred %p tid %X\n", thred, thred->id));
 }  /* pt_SuspendTest */
 static void pt_ResumeSet(PRThread *thred)
 {
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("pt_ResumeSet thred %p thread id = %X\n", thred, thred->id));
     /*
      * Clear the global state and set the thread state so that it will
      * continue past yield loop in the suspend signal handler
      */
     PR_ASSERT(thred->suspend & PT_THREAD_SUSPENDED);
     thred->suspend &= ~PT_THREAD_SUSPENDED;
 #if defined(PT_NO_SIGTIMEDWAIT)
 #if defined(SYMBIAN)
 	/* All signal group functions are not implemented in Symbian OS */
 #else
 	pthread_kill(thred->id, SIGUSR1);
 #endif
 #endif
 }  /* pt_ResumeSet */
 static void pt_ResumeTest(PRThread *thred)
 {
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	   ("Begin pt_ResumeTest thred %p thread id = %X\n", thred, thred->id));
     /*
      * Wait for the threads resume state to change
      * to indicate it is really resumed
      */
 #if defined(PT_NO_SIGTIMEDWAIT)
     pthread_mutex_lock(&thred->suspendResumeMutex);
     while ((thred->suspend & PT_THREAD_RESUMED) == 0)
     {
 	    pthread_cond_timedwait(
 	        &thred->suspendResumeCV, &thred->suspendResumeMutex, &onemillisec);
     }
     pthread_mutex_unlock(&thred->suspendResumeMutex);
 #else
     while ((thred->suspend & PT_THREAD_RESUMED) == 0) {
 		PRIntn rv = sigtimedwait(&sigwait_set, NULL, &onemillisec);
     	PR_ASSERT(-1 == rv);
 	}
 #endif
     thred->suspend &= ~PT_THREAD_RESUMED;
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, (
         "End pt_ResumeTest thred %p tid %X\n", thred, thred->id));
 }  /* pt_ResumeTest */
 static pthread_once_t pt_gc_support_control = PTHREAD_ONCE_INIT;
 PR_IMPLEMENT(void) PR_SuspendAll(void)
 {
 #ifdef DEBUG
     PRIntervalTime stime, etime;
 #endif
     PRThread* thred = pt_book.first;
     PRThread *me = PR_GetCurrentThread();
     int rv;
     rv = pthread_once(&pt_gc_support_control, init_pthread_gc_support);
     PR_ASSERT(0 == rv);
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_SuspendAll\n"));
     /*
      * Stop all threads which are marked GC able.
      */
     PR_Lock(pt_book.ml);
 #ifdef DEBUG
     suspendAllOn = PR_TRUE;
     stime = PR_IntervalNow();
 #endif
     while (thred != NULL)
     {
 	    if ((thred != me) && _PT_IS_GCABLE_THREAD(thred))
     		pt_SuspendSet(thred);
         thred = thred->next;
     }
     /* Wait till they are really suspended */
     thred = pt_book.first;
     while (thred != NULL)
     {
 	    if ((thred != me) && _PT_IS_GCABLE_THREAD(thred))
             pt_SuspendTest(thred);
         thred = thred->next;
     }
     suspendAllSuspended = PR_TRUE;
 #ifdef DEBUG
     etime = PR_IntervalNow();
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,\
         ("End PR_SuspendAll (time %dms)\n",
         PR_IntervalToMilliseconds(etime - stime)));
 #endif
 }  /* PR_SuspendAll */
 PR_IMPLEMENT(void) PR_ResumeAll(void)
 {
 #ifdef DEBUG
     PRIntervalTime stime, etime;
 #endif
     PRThread* thred = pt_book.first;
     PRThread *me = PR_GetCurrentThread();
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_ResumeAll\n"));
     /*
      * Resume all previously suspended GC able threads.
      */
     suspendAllSuspended = PR_FALSE;
 #ifdef DEBUG
     stime = PR_IntervalNow();
 #endif
     while (thred != NULL)
     {
 	    if ((thred != me) && _PT_IS_GCABLE_THREAD(thred))
     	    pt_ResumeSet(thred);
         thred = thred->next;
     }
     thred = pt_book.first;
     while (thred != NULL)
     {
 	    if ((thred != me) && _PT_IS_GCABLE_THREAD(thred))
     	    pt_ResumeTest(thred);
         thred = thred->next;
     }
     PR_Unlock(pt_book.ml);
 #ifdef DEBUG
     suspendAllOn = PR_FALSE;
     etime = PR_IntervalNow();
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
         ("End PR_ResumeAll (time %dms)\n",
         PR_IntervalToMilliseconds(etime - stime)));
 #endif
 }  /* PR_ResumeAll */
 /* Return the stack pointer for the given thread- used by the GC */
 PR_IMPLEMENT(void *)PR_GetSP(PRThread *thred)
 {
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS,
 	    ("in PR_GetSP thred %p thid = %X, sp = %p\n",
 	    thred, thred->id, thred->sp));
     return thred->sp;
 }  /* PR_GetSP */
 #else /* !defined(_PR_DCETHREADS) */
 static pthread_once_t pt_gc_support_control = pthread_once_init;
 /*
  * For DCE threads, there is no pthread_kill or a way of suspending or resuming a
  * particular thread.  We will just disable the preemption (virtual timer alarm) and
  * let the executing thread finish the garbage collection.  This stops all other threads
  * (GC able or not) and is very inefficient but there is no other choice.
  */
 PR_IMPLEMENT(void) PR_SuspendAll()
 {
     PRIntn rv;
     rv = pthread_once(&pt_gc_support_control, init_pthread_gc_support);
     PR_ASSERT(0 == rv);  /* returns -1 on failure */
 #ifdef DEBUG
     suspendAllOn = PR_TRUE;
 #endif
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_SuspendAll\n"));
     /*
      * turn off preemption - i.e add virtual alarm signal to the set of
      * blocking signals
      */
     rv = sigprocmask(
         SIG_BLOCK, &javagc_vtalarm_sigmask, &javagc_intsoff_sigmask);
     PR_ASSERT(0 == rv);
     suspendAllSuspended = PR_TRUE;
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("End PR_SuspendAll\n"));
 }  /* PR_SuspendAll */
 PR_IMPLEMENT(void) PR_ResumeAll()
 {
     PRIntn rv;
     suspendAllSuspended = PR_FALSE;
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_ResumeAll\n"));
     /* turn on preemption - i.e re-enable virtual alarm signal */
     rv = sigprocmask(SIG_SETMASK, &javagc_intsoff_sigmask, (sigset_t *)NULL);
     PR_ASSERT(0 == rv);
 #ifdef DEBUG
     suspendAllOn = PR_FALSE;
 #endif
     PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("End PR_ResumeAll\n"));
 }  /* PR_ResumeAll */
 /* Return the stack pointer for the given thread- used by the GC */
 PR_IMPLEMENT(void*)PR_GetSP(PRThread *thred)
 {
 	pthread_t tid = thred->id;
 	char *thread_tcb, *top_sp;
 	/*
 	 * For HPUX DCE threads, pthread_t is a struct with the
 	 * following three fields (see pthread.h, dce/cma.h):
 	 *     cma_t_address       field1;
 	 *     short int           field2;
 	 *     short int           field3;
 	 * where cma_t_address is typedef'd to be either void*
 	 * or char*.
 	 */
 	PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("Begin PR_GetSP\n"));
 	thread_tcb = (char*)tid.field1;
 	top_sp = *(char**)(thread_tcb + 128);
 	PR_LOG(_pr_gc_lm, PR_LOG_ALWAYS, ("End PR_GetSP %p \n", top_sp));
 	return top_sp;
 }  /* PR_GetSP */
 #endif /* !defined(_PR_DCETHREADS) */
 PR_IMPLEMENT(PRStatus) PR_SetCurrentThreadName(const char *name)
 {
     PRThread *thread;
     size_t nameLen;
     int result;
     if (!name) {
         PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
         return PR_FAILURE;
     }
     thread = PR_GetCurrentThread();
     if (!thread)
         return PR_FAILURE;
     PR_Free(thread->name);
     nameLen = strlen(name);
     thread->name = (char *)PR_Malloc(nameLen + 1);
     if (!thread->name)
         return PR_FAILURE;
     memcpy(thread->name, name, nameLen + 1);
 #if defined(OPENBSD) || defined(FREEBSD)
     result = pthread_set_name_np(thread->id, name);
 #else /* not BSD */
     /*
      * On OSX, pthread_setname_np is only available in 10.6 or later, so test
      * for it at runtime.  It also may not be available on all linux distros.
      */
 #if defined(DARWIN)
     int (*dynamic_pthread_setname_np)(const char*);
 #else
     int (*dynamic_pthread_setname_np)(pthread_t, const char*);
 #endif
     *(void**)(&dynamic_pthread_setname_np) =
         dlsym(RTLD_DEFAULT, "pthread_setname_np");
     if (!dynamic_pthread_setname_np)
         return PR_SUCCESS;
     /*
      * The 15-character name length limit is an experimentally determined
      * length of a null-terminated string that most linux distros and OS X
      * accept as an argument to pthread_setname_np.  Otherwise the E2BIG
      * error is returned by the function.
      */
 #define SETNAME_LENGTH_CONSTRAINT 15
 #define SETNAME_FRAGMENT1_LENGTH (SETNAME_LENGTH_CONSTRAINT >> 1)
 #define SETNAME_FRAGMENT2_LENGTH \
     (SETNAME_LENGTH_CONSTRAINT - SETNAME_FRAGMENT1_LENGTH - 1)
     char name_dup[SETNAME_LENGTH_CONSTRAINT + 1];
     if (nameLen > SETNAME_LENGTH_CONSTRAINT) {
         memcpy(name_dup, name, SETNAME_FRAGMENT1_LENGTH);
         name_dup[SETNAME_FRAGMENT1_LENGTH] = '~';
         /* Note that this also copies the null terminator. */
         memcpy(name_dup + SETNAME_FRAGMENT1_LENGTH + 1,
                name + nameLen - SETNAME_FRAGMENT2_LENGTH,
                SETNAME_FRAGMENT2_LENGTH + 1);
         name = name_dup;
     }
 #if defined(DARWIN)
     result = dynamic_pthread_setname_np(name);
 #else
     result = dynamic_pthread_setname_np(thread->id, name);
 #endif
 #endif /* not BSD */
     if (result) {
         PR_SetError(PR_UNKNOWN_ERROR, result);
         return PR_FAILURE;
     }
     return PR_SUCCESS;
 }
 PR_IMPLEMENT(const char *) PR_GetThreadName(const PRThread *thread)
 {
     if (!thread)
         return NULL;
     return thread->name;
 }
 #endif  /* defined(_PR_PTHREADS) || defined(_PR_DCETHREADS) */
 /* ptthread.c */

The Tor Browser / annotate

nsprpub/pr/src/pthreads/ptthread.c@6474c204b198 (annotated)

nsprpub/pr/src/pthreads/ptthread.c