Files
pcas/src/libCom/osi/epicsThread.cpp
Andrew Johnson 14ea2740d1 Oops.
2008-08-28 15:42:09 +00:00

325 lines
9.3 KiB
C++

/*************************************************************************\
* Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
* National Laboratory.
* Copyright (c) 2002 The Regents of the University of California, as
* Operator of Los Alamos National Laboratory.
* EPICS BASE is distributed subject to a Software License Agreement found
* in file LICENSE that is included with this distribution.
\*************************************************************************/
//
// $Id$
//
// Author: Jeff Hill
//
#include <exception>
#include <typeinfo>
#include <stdio.h>
#include <stddef.h>
#include <float.h>
#define epicsExportSharedSymbols
#include "epicsTime.h"
#include "epicsThread.h"
#include "epicsAssert.h"
#include "epicsGuard.h"
#include "errlog.h"
epicsThreadRunable::~epicsThreadRunable () {}
void epicsThreadRunable::run () {}
void epicsThreadRunable::show ( unsigned int ) const {}
// vxWorks 5.4 gcc fails during compile when I use std::exception
using namespace std;
// exception payload
class epicsThread::unableToCreateThread : public exception {
const char * what () const throw () {
return "epicsThread class was unable to create a new thread";
}
};
// exception payload
class epicsThread::exitException : public exception {
const char * what () const throw () {
return "epicsThread class's private exit exception";
}
};
extern "C" void epicsThreadCallEntryPoint ( void * pPvt )
{
epicsThread * pThread =
static_cast <epicsThread *> ( pPvt );
bool waitRelease = false;
try {
pThread->pWaitReleaseFlag = & waitRelease;
if ( pThread->beginWait () ) {
pThread->runable.run ();
// current thread may have run the destructor
// so must not touch the this pointer from
// here on down if waitRelease is true
}
}
catch ( const epicsThread::exitException & ) {
}
catch ( std::exception & except ) {
if ( ! waitRelease ) {
epicsTime cur = epicsTime::getCurrent ();
char date[64];
cur.strftime ( date, sizeof ( date ), "%a %b %d %Y %H:%M:%S.%f");
char name [128];
epicsThreadGetName ( pThread->id, name, sizeof ( name ) );
errlogPrintf (
"epicsThread: Unexpected C++ exception \"%s\" with type \"%s\" in thread \"%s\" at %s\n",
except.what (), typeid ( except ).name (), name, date );
// this should behave as the C++ implementation intends when an
// exception isnt handled. If users dont like this behavior, they
// can install an application specific unexpected handler.
unexpected ();
}
}
catch ( ... ) {
if ( ! waitRelease ) {
epicsTime cur = epicsTime::getCurrent ();
char date[64];
cur.strftime ( date, sizeof ( date ), "%a %b %d %Y %H:%M:%S.%f");
char name [128];
epicsThreadGetName ( pThread->id, name, sizeof ( name ) );
errlogPrintf (
"epicsThread: Unknown C++ exception in thread \"%s\" at %s\n",
name, date );
// this should behave as the C++ implementation intends when an
// exception isnt handled. If users dont like this behavior, they
// can install an application specific unexpected handler.
unexpected ();
}
}
if ( ! waitRelease ) {
epicsGuard < epicsMutex > guard ( pThread->mutex );
pThread->terminated = true;
pThread->exitEvent.signal ();
// once the terminated flag is set and we release the lock
// then the "this" pointer must not be touched again
}
}
bool epicsThread::beginWait () throw ()
{
epicsGuard < epicsMutex > guard ( this->mutex );
while ( ! this->begin && ! this->cancel ) {
epicsGuardRelease < epicsMutex > unguard ( guard );
this->event.wait ();
}
return this->begin && ! this->cancel;
}
void epicsThread::exit ()
{
throw exitException ();
}
void epicsThread::exitWait () throw ()
{
assert ( this->exitWait ( DBL_MAX ) );
}
bool epicsThread::exitWait ( const double delay ) throw ()
{
// if destructor is running in managed thread then of
// course we will not wait for the managed thread to
// exit
if ( this->isCurrentThread() ) {
if ( this->pWaitReleaseFlag ) {
*this->pWaitReleaseFlag = true;
}
return true;
}
epicsTime exitWaitBegin = epicsTime::getCurrent ();
double exitWaitElapsed = 0.0;
epicsGuard < epicsMutex > guard ( this->mutex );
this->cancel = true;
while ( ! this->terminated ) {
epicsGuardRelease < epicsMutex > unguard ( guard );
this->event.signal ();
this->exitEvent.wait ( delay - exitWaitElapsed );
epicsTime current = epicsTime::getCurrent ();
exitWaitElapsed = current - exitWaitBegin;
if ( exitWaitElapsed >= delay ) {
break;
}
}
return this->terminated;
}
epicsThread::epicsThread (
epicsThreadRunable & runableIn, const char * pName,
unsigned stackSize, unsigned priority ) :
runable ( runableIn ), id ( 0 ), pWaitReleaseFlag ( 0 ),
begin ( false ), cancel ( false ), terminated ( false )
{
this->id = epicsThreadCreate (
pName, priority, stackSize, epicsThreadCallEntryPoint,
static_cast < void * > ( this ) );
if ( ! this->id ) {
throw unableToCreateThread ();
}
}
epicsThread::~epicsThread () throw ()
{
while ( ! this->exitWait ( 10.0 ) ) {
char nameBuf [256];
this->getName ( nameBuf, sizeof ( nameBuf ) );
fprintf ( stderr,
"epicsThread::~epicsThread(): "
"blocking for thread \"%s\" to exit\n",
nameBuf );
fprintf ( stderr,
"was epicsThread object destroyed before thread exit ?\n");
}
}
void epicsThread::start () throw ()
{
{
epicsGuard < epicsMutex > guard ( this->mutex );
this->begin = true;
}
this->event.signal ();
}
bool epicsThread::isCurrentThread () const throw ()
{
return ( epicsThreadGetIdSelf () == this->id );
}
void epicsThread::resume () throw ()
{
epicsThreadResume ( this->id );
}
void epicsThread::getName ( char *name, size_t size ) const throw ()
{
epicsThreadGetName ( this->id, name, size );
}
epicsThreadId epicsThread::getId () const throw ()
{
return this->id;
}
unsigned int epicsThread::getPriority () const throw ()
{
return epicsThreadGetPriority (this->id);
}
void epicsThread::setPriority (unsigned int priority) throw ()
{
epicsThreadSetPriority (this->id, priority);
}
bool epicsThread::priorityIsEqual (const epicsThread &otherThread) const throw ()
{
if ( epicsThreadIsEqual (this->id, otherThread.id) ) {
return true;
}
return false;
}
bool epicsThread::isSuspended () const throw ()
{
if ( epicsThreadIsSuspended (this->id) ) {
return true;
}
return false;
}
bool epicsThread::operator == (const epicsThread &rhs) const throw ()
{
return (this->id == rhs.id);
}
void epicsThread::suspendSelf () throw ()
{
epicsThreadSuspendSelf ();
}
void epicsThread::sleep (double seconds) throw ()
{
epicsThreadSleep (seconds);
}
//epicsThread & epicsThread::getSelf ()
//{
// return * static_cast<epicsThread *> ( epicsThreadGetIdSelf () );
//}
const char *epicsThread::getNameSelf () throw ()
{
return epicsThreadGetNameSelf ();
}
bool epicsThread::isOkToBlock () throw ()
{
return epicsThreadIsOkToBlock() != 0;
}
void epicsThread::setOkToBlock(bool isOkToBlock) throw ()
{
epicsThreadSetOkToBlock(static_cast<int>(isOkToBlock));
}
class epicsThreadPrivateBase::unableToCreateThreadPrivate : public exception {
const char * what () const throw ()
{
return "epicsThreadPrivate:: unable to create thread private variable";
}
};
void epicsThreadPrivateBase::throwUnableToCreateThreadPrivate ()
{
throw epicsThreadPrivateBase::unableToCreateThreadPrivate ();
}
extern "C" {
static epicsThreadOnceId okToBlockOnce = EPICS_THREAD_ONCE_INIT;
epicsThreadPrivateId okToBlockPrivate;
static const int okToBlockNo = 0;
static const int okToBlockYes = 1;
static void epicsThreadOnceIdInit(void *)
{
okToBlockPrivate = epicsThreadPrivateCreate();
}
int epicsShareAPI epicsThreadIsOkToBlock(void)
{
const int *pokToBlock;
epicsThreadOnce(&okToBlockOnce, epicsThreadOnceIdInit, NULL);
pokToBlock = (int *) epicsThreadPrivateGet(okToBlockPrivate);
return (pokToBlock ? *pokToBlock : 0);
}
void epicsShareAPI epicsThreadSetOkToBlock(int isOkToBlock)
{
const int *pokToBlock;
epicsThreadOnce(&okToBlockOnce, epicsThreadOnceIdInit, NULL);
pokToBlock = (isOkToBlock) ? &okToBlockYes : &okToBlockNo;
epicsThreadPrivateSet(okToBlockPrivate, (void *)pokToBlock);
}
epicsThreadId epicsShareAPI epicsThreadMustCreate (
const char *name, unsigned int priority, unsigned int stackSize,
EPICSTHREADFUNC funptr,void *parm)
{
epicsThreadId id = epicsThreadCreate (
name, priority, stackSize, funptr, parm );
assert ( id );
return id;
}
} // extern "C"
// Ensure the main thread gets a unique ID
static epicsThreadId epicsThreadMainId = epicsThreadGetIdSelf();