public void run() {
Lib.debug('t', "### Try to listen from " + KThread.currentThread().toString());
int res = comm.listen();
Lib.debug('t', "### listened " + res + " from " + KThread.currentThread().toString());
}
/**
* The exception handler. This handler is called by the processor whenever
* a user instruction causes a processor exception.
*
* <p>
* When the exception handler is invoked, interrupts are enabled, and the
* processor's cause register contains an integer identifying the cause of
* the exception (see the <tt>exceptionZZZ</tt> constants in the
* <tt>Processor</tt> class). If the exception involves a bad virtual
* address (e.g. page fault, TLB miss, read-only, bus error, or address
* error), the processor's BadVAddr register identifies the virtual address
* that caused the exception.
*/
public void exceptionHandler() {
Lib.assert(KThread.currentThread() instanceof UThread);
UserProcess process = ((UThread) KThread.currentThread()).process;
int cause = Machine.processor().readRegister(Processor.regCause);
process.handleException(cause);
}
public void run() {
lock.acquire();
System.out.print(KThread.currentThread().getName() + " acquired lock\n");
condition.sleep();
System.out.print(KThread.currentThread().getName() + " acquired lock again\n");
lock.release();
System.out.print(KThread.currentThread().getName() + " released lock \n");
}
/**
* Put the current thread to sleep for at least <i>x</i> ticks, waking it up in the timer
* interrupt handler. The thread must be woken up (placed in the scheduler ready set) during the
* first timer interrupt where
*
* <p>
*
* <blockquote>
*
* (current time) >= (WaitUntil called time)+(x)
*
* </blockquote>
*
* @param x the minimum number of clock ticks to wait.
* @see nachos.machine.Timer#getTime()
*/
public void waitUntil(long x) {
// disable interrupts
Machine.interrupt().disable(); // let's see if this works? DAC DEBUG
// calculate wakeTime
long wakeTime = Machine.timer().getTime() + x;
// create AlarmBucket
AlarmBucket Abuck = new AlarmBucket(wakeTime, KThread.currentThread());
// add current thread (alarm bucket) to waitQueue
waitQueue.add(Abuck);
// put current thread to sleep
KThread.currentThread().sleep();
return;
}
/**
* Start running user programs, by creating a process and running a shell
* program in it. The name of the shell program it must run is returned by
* <tt>Machine.getShellProgramName()</tt>.
*
* @see nachos.machine.Machine#getShellProgramName
*/
public void run() {
super.run();
UserProcess process = UserProcess.newUserProcess();
String shellProgram = Machine.getShellProgramName();
Lib.assert(process.execute(shellProgram, new String[] { }));
KThread.currentThread().finish();
}
/**
* Atomically release the associated lock and go to sleep on this condition variable until another
* thread wakes it using <tt>wake()</tt>. The current thread must hold the associated lock. The
* thread will automatically reacquire the lock before <tt>sleep()</tt> returns.
*/
public void sleep() {
Lib.assertTrue(conditionLock.isHeldByCurrentThread());
boolean intStatus = Machine.interrupt().disable();
conditionLock.release();
waitQueue.waitForAccess(KThread.currentThread());
KThread.sleep();
conditionLock.acquire();
Machine.interrupt().restore(intStatus);
}
/**
* The timer interrupt handler. This is called by the machine's timer periodically (approximately
* every 500 clock ticks). Causes the current thread to yield, forcing a context switch if there
* is another thread that should be run.
*/
public void timerInterrupt() {
// disable interrupts (maybe not necessary)
Machine.interrupt().disable(); // let's see if this works?
// get current time
long currentTime = Machine.timer().getTime();
// go through waitQueue and put each thread that is "less than" current wait time on ready queue
AlarmBucket placeholder = null;
int count = waitQueue.size();
while (count > 0) {
placeholder = waitQueue.peek();
if (placeholder.getTime() <= currentTime) {
placeholder = waitQueue.poll();
placeholder.getKThread().ready();
count = waitQueue.size();
} else {
count = 0;
}
}
// yield current thread
KThread.currentThread().yield();
// Machine.interrupt().enable(); //let's see if this works? DAC DEBUG
}
public void run() {
Lib.debug('t', "### Speak " + word + " from " + KThread.currentThread().toString());
comm.speak(word);
}
/**
* Returns the current process.
*
* @return the current process, or <tt>null</tt> if no process is current.
*/
public static UserProcess currentProcess() {
if (!(KThread.currentThread() instanceof UThread))
return null;
return ((UThread) KThread.currentThread()).process;
}
