libcw/cwThread.cpp

333 lines
7.4 KiB
C++

#include "cwCommon.h"
#include "cwLog.h"
#include "cwCommonImpl.h"
#include "cwMem.h"
#include "cwThread.h"
#include <pthread.h>
namespace cw
{
namespace thread
{
enum
{
kDoExitThFl = 0x01,
kDoPauseThFl = 0x02,
kDoRunThFl = 0x04
};
typedef struct thread_str
{
pthread_t pThreadH;
std::atomic<stateId_t> stateId;
std::atomic<unsigned> doFlags;
cbFunc_t func;
void* funcArg;
unsigned stateMicros;
unsigned pauseMicros;
unsigned sleepMicros;
pthread_attr_t attr;
} thread_t;
inline thread_t* _handleToPtr(handle_t h) { return handleToPtr<handle_t,thread_t>(h); }
// Called from client thread to wait for the internal thread to transition to a specified state.
rc_t _waitForState( thread_t* p, unsigned stateId )
{
unsigned waitTimeMicroSecs = 0;
stateId_t curStateId;
do
{
curStateId = p->stateId.load(std::memory_order_acquire);
if(curStateId == stateId )
break;
sleepUs( p->sleepMicros );
waitTimeMicroSecs += p->sleepMicros;
}while( waitTimeMicroSecs < p->stateMicros );
return curStateId==stateId ? kOkRC : kTimeOutRC;
}
void _threadCleanUpCallback(void* p)
{
((thread_t*)p)->stateId.store(kExitedThId,std::memory_order_release);
}
void* _threadCallback(void* param)
{
thread_t* p = (thread_t*)param;
// set a clean up handler - this will be called when the
// thread terminates unexpectedly or pthread_cleanup_pop() is called.
pthread_cleanup_push(_threadCleanUpCallback,p);
unsigned curDoFlags = 0;
do
{
// get the current thread state (running or paused)
stateId_t curStateId = p->stateId.load(std::memory_order_relaxed);
// if we are in the pause state
if( curStateId == kPausedThId )
{
sleepUs( p->pauseMicros );
curDoFlags = p->doFlags.load(std::memory_order_acquire);
// check if we have been requested to leave the pause state
if( cwIsFlag(curDoFlags,kDoRunThFl) )
{
p->stateId.store(kRunningThId,std::memory_order_release);
}
}
else // ... we are in running state
{
// call the user-defined function
if( p->func(p->funcArg)==false )
break;
curDoFlags = p->doFlags.load(std::memory_order_acquire);
// check if we have been requested to enter the pause state
if( cwIsFlag(curDoFlags,kDoPauseThFl) )
{
p->stateId.store(kPausedThId,std::memory_order_release);
}
}
}while( cwIsFlag(curDoFlags,kDoExitThFl) == false );
pthread_cleanup_pop(1);
pthread_exit(NULL);
return p;
}
}
}
cw::rc_t cw::thread::create( handle_t& hRef, cbFunc_t func, void* funcArg, int stateMicros, int pauseMicros )
{
rc_t rc;
int sysRC;
if((rc = destroy(hRef)) != kOkRC )
return rc;
thread_t* p = mem::allocZ<thread_t>();
p->func = func;
p->funcArg = funcArg;
p->stateMicros = stateMicros;
p->pauseMicros = pauseMicros;
p->stateId = kPausedThId;
p->sleepMicros = 15000;
if((sysRC = pthread_attr_init(&p->attr)) != 0)
{
p->stateId = kNotInitThId;
rc = cwLogSysError(kOpFailRC,sysRC,"Thread attribute init failed.");
}
else
/*
// Creating the thread in a detached state should prevent it from leaking memory when
// the thread is closed and pthread_join() is not called but it doesn't seem to work anymore ????
if ((sysRC = pthread_attr_setdetachstate(&p->attr, PTHREAD_CREATE_DETACHED)) != 0)
{
p->stateId = kNotInitThId;
rc = cwLogSysError(kOpFailRC,sysRC,"Thread set detach attribute failed.");
}
else
*/
if((sysRC = pthread_create(&p->pThreadH, &p->attr, _threadCallback, (void*)p )) != 0 )
{
p->stateId = kNotInitThId;
rc = cwLogSysError(kOpFailRC,sysRC,"Thread create failed.");
}
hRef.set(p);
return rc;
}
cw::rc_t cw::thread::destroy( handle_t& hRef )
{
rc_t rc = kOkRC;
int sysRC;
if( !hRef.isValid() )
return rc;
thread_t* p = _handleToPtr(hRef);
// tell the thread to exit
p->doFlags.store(kDoExitThFl,std::memory_order_release);
// wait for the thread to exit and then deallocate the thread object
if((rc = _waitForState(p,kExitedThId)) != kOkRC )
return cwLogError(rc,"Thread timed out waiting for destroy.");
// Block until the thread is actually fully cleaned up
if((sysRC = pthread_join(p->pThreadH,NULL)) != 0)
rc = cwLogSysError(kOpFailRC,sysRC,"Thread join failed.");
//if( pthread_attr_destroy(&p->attr) != 0 )
// rc = cwLogError(kOpFailRC,"Thread attribute destroy failed.");
mem::release(p);
hRef.clear();
return rc;
}
cw::rc_t cw::thread::pause( handle_t h, unsigned cmdFlags )
{
rc_t rc = kOkRC;
bool pauseFl = cwIsFlag(cmdFlags,kPauseFl);
bool waitFl = cwIsFlag(cmdFlags,kWaitFl);
thread_t* p = _handleToPtr(h);
stateId_t curStateId = p->stateId.load(std::memory_order_acquire);
bool isPausedFl = curStateId == kPausedThId;
unsigned waitId;
if( isPausedFl == pauseFl )
return kOkRC;
if( pauseFl )
{
p->doFlags.store(kDoPauseThFl,std::memory_order_release);
waitId = kPausedThId;
}
else
{
p->doFlags.store(kDoRunThFl,std::memory_order_release);
waitId = kRunningThId;
}
if( waitFl )
rc = _waitForState(p,waitId);
if( rc != kOkRC )
cwLogError(rc,"Thread timed out waiting for '%s'.", pauseFl ? "pause" : "un-pause");
return rc;
}
cw::rc_t cw::thread::unpause( handle_t h )
{ return pause( h, kWaitFl); }
cw::thread::stateId_t cw::thread::state( handle_t h )
{
thread_t* p = _handleToPtr(h);
return p->stateId.load(std::memory_order_acquire);
}
cw::thread::thread_id_t cw::thread::id()
{
typedef struct
{
union
{
thread_id_t id;
pthread_t pthread_id;
} u;
} id_t;
id_t id;
id.u.pthread_id = pthread_self();
return id.u.id;
}
namespace cw
{
bool _threadTestCb( void* p )
{
unsigned* ip = (unsigned*)p;
ip[0]++;
return true;
}
}
cw::rc_t cw::threadTest()
{
thread::handle_t h;
unsigned val = 0;
rc_t rc;
char c = 0;
if((rc = thread::create(h,_threadTestCb,&val)) != kOkRC )
return rc;
if((rc = thread::pause(h,0)) != kOkRC )
goto errLabel;
cwLogInfo("o=print p=pause s=state q=quit\n");
while( c != 'q' )
{
c = (char)fgetc(stdin);
fflush(stdin);
switch(c)
{
case 'o':
cwLogInfo("val: 0x%x\n",val);
break;
case 's':
cwLogInfo("state=%i\n",thread::state(h));
break;
case 'p':
{
if( thread::state(h) == thread::kPausedThId )
rc = thread::pause(h,thread::kWaitFl);
else
rc = thread::pause(h,thread::kPauseFl|thread::kWaitFl);
if( rc == kOkRC )
cwLogInfo("new state:%i\n", thread::state(h));
else
{
cwLogError(rc,"threadPause() test failed.");
goto errLabel;
}
}
break;
case 'q':
break;
//default:
//cwLogInfo("Unknown:%c\n",c);
}
}
errLabel:
rc_t rc0 = rc = thread::destroy(h);
return rc == kOkRC ? rc0 : rc;
}