added process scheduling algorithms

process-scheduling/algorithms/rr.typ

@@ -0,0 +1,81 @@
+#import "utils.typ": *
+
+#let RR(tasks, quantum: 2, ctx-switch: 1) = {
+  let (processes, tasks) = _prepare-tasks(tasks)
+
+  let n-tasks = tasks.len()
+  let cur-time = 0
+  let current = none
+  let finished = 0
+  let running = 0
+  let last-running = none
+  let logs = ()
+  let failsafe = 0
+
+  while (failsafe < 160 and finished < n-tasks) {
+    failsafe += 1
+    for (i, p) in tasks.enumerate() {
+      if p.state == TERMINATED {
+        continue
+      }
+      logs.push("Current time: " + str(cur-time) + ", pid: " + str(p.pid))
+
+      if p.state == UNBORN {
+        if p.arrival <= cur-time {
+          p.state = READY
+          if running == 0 {
+            processes.at(p.id).events.push((RUNNING, p.arrival))
+          } else {
+            processes.at(p.id).events.push((READY, p.arrival))
+          }
+          running += 1
+          if last-running != none {
+            logs.push("Preempting last running process (current time: " + str(cur-time) + ", pid: " + str(last-running.pid) + ")")
+            processes.at(last-running.id).events.push((READY, cur-time))
+            cur-time += ctx-switch
+          }
+          logs.push("Process " + str(p.pid) + " is now ready")
+          logs.push("Running processes: " + str(running))
+        }
+      }
+
+      if p.state == READY {
+        //if running > 1 {
+        if last-running == none or last-running.pid != p.pid {
+          processes.at(p.id).events.push((RUNNING, cur-time))
+        }
+        p.remaining -= quantum
+        cur-time += quantum
+        last-running = p
+        logs.push("Executing quantum for process " + str(p.pid) + ", remaining time " + str(p.remaining))
+
+        if p.remaining <= 0 {
+          logs.push("  Process has finished")
+          processes.at(p.id).events.push((TERMINATED, cur-time + p.remaining))
+          p.remaining = 0
+          p.state = TERMINATED
+          last-running = none
+          finished += 1
+          running -= 1
+        
+        } else if running > 1 {
+          logs.push("  Preempting process (current time: " + str(cur-time) + ", pid: " + str(p.pid) + ")")
+          last-running = none
+          processes.at(p.id).events.push((READY, cur-time))
+          cur-time += ctx-switch
+        }
+      }
+
+      tasks.at(i) = p
+    }
+    if finished < n-tasks and running == 0 {
+      cur-time += 1
+    }
+  }
+
+  let f = failsafe
+
+  //let logs2 = logs.slice(-60)
+
+  return _prepare-output(processes)
+}