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#include "threads.hh"
struct TThreadStarter {
ThreadFunction *Function;
void *Argument;
bool Detach;
};
static void *ThreadStarter(void *Pointer){
TThreadStarter *Starter = (TThreadStarter*)Pointer;
ThreadFunction *Function = Starter->Function;
void *Argument = Starter->Argument;
bool Detach = Starter->Detach;
delete Starter;
int Result = Function(Argument);
// TODO(fusion): Just store the integer as a pointer and avoid allocation?
int *ResultPointer = NULL;
if(!Detach){
ResultPointer = new int;
*ResultPointer = Result;
}
pthread_exit(ResultPointer);
return NULL; // Unreachable.
}
ThreadHandle StartThread(ThreadFunction *Function, void *Argument, bool Detach){
TThreadStarter *Starter = new TThreadStarter;
Starter->Function = Function;
Starter->Argument = Argument;
Starter->Detach = Detach;
pthread_t Handle;
int err = pthread_create(&Handle, NULL, ThreadStarter, Starter);
if(err != 0){
error("StartThread: Kann Thread nicht anlegen; Fehlercode %d.\n", err);
return INVALID_THREAD_HANDLE;
}
if(Detach){
pthread_detach(Handle);
}
return (ThreadHandle)Handle;
}
ThreadHandle StartThread(ThreadFunction *Function, void *Argument, size_t StackSize, bool Detach){
TThreadStarter *Starter = new TThreadStarter;
Starter->Function = Function;
Starter->Argument = Argument;
Starter->Detach = Detach;
pthread_t Handle;
pthread_attr_t Attr;
pthread_attr_init(&Attr);
pthread_attr_setstacksize(&Attr, StackSize);
int err = pthread_create(&Handle, &Attr, ThreadStarter, Starter);
pthread_attr_destroy(&Attr);
if(err != 0){
error("StartThread: Kann Thread nicht anlegen; Fehlercode %d.\n", err);
return INVALID_THREAD_HANDLE;
}
if(Detach){
pthread_detach(Handle);
}
return (ThreadHandle)Handle;
}
ThreadHandle StartThread(ThreadFunction *Function, void *Argument, void *Stack, size_t StackSize, bool Detach){
TThreadStarter *Starter = new TThreadStarter;
Starter->Function = Function;
Starter->Argument = Argument;
Starter->Detach = Detach;
pthread_t Handle;
pthread_attr_t Attr;
pthread_attr_init(&Attr);
pthread_attr_setstack(&Attr, Stack, StackSize);
int err = pthread_create(&Handle, &Attr, ThreadStarter, Starter);
pthread_attr_destroy(&Attr);
if(err != 0){
error("StartThread: Kann Thread nicht anlegen; Fehlercode %d.\n", err);
return INVALID_THREAD_HANDLE;
}
if(Detach){
pthread_detach(Handle);
}
return (ThreadHandle)Handle;
}
int JoinThread(ThreadHandle Handle){
int Result = 0;
int *ResultPointer;
pthread_join((pthread_t)Handle, (void**)&ResultPointer);
if(ResultPointer != NULL){
Result = *ResultPointer;
delete ResultPointer;
}
return Result;
}
void DelayThread(int Seconds, int MicroSeconds){
if(Seconds == 0 && MicroSeconds == 0){
sched_yield();
}else if(MicroSeconds == 0){
sleep(Seconds);
}else{
usleep(MicroSeconds + Seconds * 1000000);
}
}
Semaphore::Semaphore(int Value){
this->value = Value;
// TODO(fusion): These should probably be non-recoverable errors.
if(pthread_mutex_init(&this->mutex, NULL) != 0){
error("Semaphore::Semaphore: Kann Mutex nicht einrichten.\n");
}
if(pthread_cond_init(&this->condition, NULL) != 0){
error("Semaphore::Semaphore: Kann Wartebedingung nicht einrichten.\n");
}
}
Semaphore::~Semaphore(void){
// IMPORTANT(fusion): Due to how initialization is rolled out, `exit` may be
// called after threads are spawned but before `ExitAll` is registered as an
// exit handler. This means such threads may still be running or left global
// semaphores in an inconsistent state if abruptly terminated. Either way,
// they are still considered "in use".
// In this case, calling `destroy` on either mutex or condition variable is
// undefined behaviour as per the manual but the actual implementation would
// fail on `mutex_destroy` with `EBUSY` and hang on `cond_destroy`.
// The temporary solution is to check the result from `mutex_destroy` before
// attempting to call `cond_destroy` to avoid hanging at exit.
int ErrorCode;
if((ErrorCode = pthread_mutex_destroy(&this->mutex)) != 0){
error("Semaphore::~Semaphore: Kann Mutex nicht freigeben: (%d) %s.\n",
ErrorCode, strerrordesc_np(ErrorCode));
}else if((ErrorCode = pthread_cond_destroy(&this->condition)) != 0){
error("Semaphore::~Semaphore: Kann Wartebedingung nicht freigeben: (%d) %s.\n",
ErrorCode, strerrordesc_np(ErrorCode));
}
}
void Semaphore::down(void){
pthread_mutex_lock(&this->mutex);
while(this->value <= 0){ // TODO(fusion): Make sure this is always a load operation?
pthread_cond_wait(&this->condition, &this->mutex);
}
this->value -= 1;
pthread_mutex_unlock(&this->mutex);
}
void Semaphore::up(void){
pthread_mutex_lock(&this->mutex);
this->value += 1;
pthread_mutex_unlock(&this->mutex);
pthread_cond_signal(&this->condition);
}
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