Sam Landsman

src/Process.js

@@ -16,11 +16,14 @@ class Process {
     }
 
     setParentQueue(queue) {
-
+        this.queue = queue
     }
 
     isFinished() {
-
+        if (this.cpuTimeNeeded <= 0 && this.blockingTimeNeeded <= 0) {
+            return true
+        }
+        return false;
     }
 
     // If no blocking time is needed by this process, decrement the amount of 
@@ -29,7 +32,15 @@ class Process {
     // by emitting the appropriate interrupt
     // Make sure the `stateChanged` flag is toggled appropriately
     executeProcess(time) {
-
+        if (this.blockingTimeNeeded == 0) {
+            if (time > this.cpuTimeNeeded) {
+                time = this.cpuTimeNeeded;
+            }
+            this.cpuTimeNeeded -= time;
+        } else {
+            this.queue.emitInterrupt(this, SchedulerInterrupt.PROCESS_BLOCKED);
+            this.stateChanged = !this.stateChanged;
+        }
    }
 
    // If this process requires blocking time, decrement the amount of blocking
@@ -38,16 +49,32 @@ class Process {
    // top running queue by emitting the appropriate interrupt
    // Make sure the `stateChanged` flag is toggled appropriately
     executeBlockingProcess(time) {
-
+        this.blockingTimeNeeded -= time;
+        if (this.blockingTimeNeeded < 0) {
+            this.blockingTimeNeeded = 0;
+        }
+        if (this.blockingTimeNeeded === 0) {
+            this.queue.emitInterrupt(this, SchedulerInterrupt.PROCESS_READY);
+            this.stateChanged = !this.stateChanged
+        }
+        // if (time > this.blockingTimeNeeded) {
+        //     time = this.blockingTimeNeeded;
+        // }
+        // if (this.blockingTimeNeeded > 0) {
+        //     this.blockingTimeNeeded -= time;
+        // } else {
+        //     this.queue.emitInterrupt(this, SchedulerInterrupt.PROCESS_READY);
+        //     this.stateChanged = !this.stateChanged;
+        // }
     }
 
     // Returns this process's stateChanged property
     isStateChanged() {
-
+        return this.stateChanged;
     }
 
     get pid() {
-
+        return this._pid;
     }
 
     // Private function used for testing; DO NOT MODIFY

src/Queue.js

@@ -19,56 +19,80 @@ class Queue {
 
     // Enqueues the given process. Return the enqueue'd process
     enqueue(process) {
-
+        this.processes.push(process);
+        process.setParentQueue(this);
+        return process;
     }
 
     // Dequeues the next process in the queue. Return the dequeue'd process
     dequeue() {
-
+        return this.processes.shift();
     }
 
     // Return the least-recently added process without removing it from the list of processes
     peek() {
-
+        return this.processes[0];
     }
 
     isEmpty() {
-
+        if (this.processes.length <= 0) {
+            return true;
+        } else {
+            return false;
+        }
     }
 
     getPriorityLevel() {
-
+        return this.priorityLevel;
     }
 
     getQueueType() {
-
+        return this.queueType;
     }
 
     // Manages a process's execution for the given amount of time
     // Processes that have had their states changed should not be affected
     // Once a process has received the alloted time, it needs to be dequeue'd and 
     // then handled accordingly, depending on whether it has finished executing or not
     manageTimeSlice(currentProcess, time) {
-
+        if (currentProcess.stateChanged == true) {
+            this.quantumClock = 0;
+            return;
+        } else {
+            this.quantumClock += time;
+            if (this.quantumClock >= this.quantum) {
+                this.quantumClock = 0;
+                this.dequeue();
+                if (!currentProcess.isFinished()) {
+                    this.scheduler.handleInterrupt(this, currentProcess, SchedulerInterrupt.LOWER_PRIORITY);
+                }
+            }
+        }
     }
 
     // Execute the next non-blocking process (assuming this is a CPU queue)
     // This method should call `manageTimeSlice` as well as execute the next running process
     doCPUWork(time) {
-
+        const process = this.peek();
+        process.executeProcess(time);
+        this.manageTimeSlice(process, time);
     }
 
     // Execute the next blocking process (assuming this is the blocking queue)
     // This method should call `manageTimeSlice` as well as execute the next blocking process
     doBlockingWork(time) {
-
+        const process = this.peek();
+        process.executeBlockingProcess(time);
+        this.manageTimeSlice(process, time);
     }
 
     // The queue's interrupt handler for notifying when a process needs to be moved to a different queue
     // Should handle PROCESS_BLOCKED and PROCESS_READY interrupts
     // The process also needs to be removed from the queue
     emitInterrupt(source, interrupt) {
-
+        const sourceIndex = this.processes.indexOf(source);
+        this.processes.splice(sourceIndex, 1);
+        this.scheduler.handleInterrupt(this, source, interrupt);
     }
 }
 

src/Scheduler.js

@@ -24,21 +24,68 @@ class Scheduler {
     // On every iteration of the scheduler, if the blocking queue is not empty, blocking work
     // should be done. Once the blocking work has been done, perform some CPU work in the same iteration.
     run() {
-
+        while (this.allQueuesEmpty() === false) {
+            const time = Date.now()
+            const forTimeSlice = time - this.clock;
+            if (this.blockingQueue.isEmpty() === false) {
+                this.blockingQueue.doBlockingWork(forTimeSlice);
+            } else {
+                this.runningQueues.forEach(cpuQ =>{
+                    if (!cpuQ.isEmpty()) {
+                        cpuQ.doCPUWork(forTimeSlice);
+                    }
+                })
+            }
+            this.clock = time;
+        }
+        // while (this.blockingQueue) {
+        //     this.blockingQueue.doBlockingWork(this.clock - Date.now());
+        //     this.clock = Date.now();
+        // }
+        // while (this.runningQueues) {
+        //     for (let i = 0; i < PRIORITY_LEVELS; i++) {
+        //         this.runningQueues[i].doCPUWork(this.clock - Date.now());
+        //         this.clock = Date.now();
+        //     }
+        // }
     }
 
     allQueuesEmpty() {
-
+        let empty = true;
+        for (let i = 0; i < PRIORITY_LEVELS; i++) {
+            if (this.runningQueues[i].isEmpty() === false) {
+                empty = false;
+            }
+        }
+        if (this.blockingQueue.isEmpty() === false) {
+            empty = false;
+        }
+        return empty;
     }
 
     addNewProcess(process) {
-
+        this.runningQueues[0].enqueue(process);
     }
 
     // The scheduler's interrupt handler that receives a queue, a process, and an interrupt string constant
     // Should handle PROCESS_BLOCKED, PROCESS_READY, and LOWER_PRIORITY interrupts.
     handleInterrupt(queue, process, interrupt) {
-
+        switch(interrupt) {
+            case "PROCESS_BLOCKED":
+                this.blockingQueue.enqueue(process);
+                break;
+            case "PROCESS_READY":
+                this.addNewProcess(process);
+                break;
+            case "LOWER_PRIORITY":
+                const currentQueue = this.runningQueues.indexOf(queue);
+                if (this.runningQueues[currentQueue + 1] && queue.getQueueType() === 'CPU_QUEUE') {
+                    this.runningQueues[currentQueue + 1].enqueue(process);
+                } else {
+                    queue.enqueue(process);
+                }
+                break;
+        }
     }
 
     // Private function used for testing; DO NOT MODIFY