jsos

shell.js

(22431B)

 /* ------------
    Shell.js
    
    The OS Shell - The "command line interface" (CLI) or interpreter for the console.
    ------------ */
 
 // TODO: Write a base class / prototype for system services and let Shell inherit from it.
 
 function Shell()
 {
     // Properties
     this.promptStr   = "$";
     this.commandList = [];
     this.curses      = "[fuvg],[cvff],[shpx],[phag],[pbpxfhpxre],[zbgureshpxre],[gvgf]";
     this.apologies   = "[sorry]";
     // Methods
     this.init        = shellInit;
     this.putPrompt   = shellPutPrompt;
     this.handleInput = shellHandleInput;
     this.execute     = shellExecute;
 }
 
 function shellInit()
 {
     var sc = null;
     //
     // Load the command list.
 
     // ver
     sc = new ShellCommand();
     sc.command = "ver";
     sc.description = "- Displays the current version data."
     sc.function = shellVer;
     this.commandList[this.commandList.length] = sc;
     
     // help
     sc = new ShellCommand();
     sc.command = "help";
     sc.description = "- This is the help command. Seek help."
     sc.function = shellHelp;
     this.commandList[this.commandList.length] = sc;
     
     // shutdown
     sc = new ShellCommand();
     sc.command = "shutdown";
     sc.description = "- Shuts down the virtual OS but leaves the underlying hardware simulation running."
     sc.function = shellShutdown;
     this.commandList[this.commandList.length] = sc;
 
     // cls
     sc = new ShellCommand();
     sc.command = "cls";
     sc.description = "- Clears the screen and resets the cursosr position."
     sc.function = shellCls;
     this.commandList[this.commandList.length] = sc;
 
     // man <topic>
     sc = new ShellCommand();
     sc.command = "man";
     sc.description = "<topic> - Displays the MANual page for <topic>.";
     sc.function = shellMan;
     this.commandList[this.commandList.length] = sc;
     
     // trace <on | off>
     sc = new ShellCommand();
     sc.command = "trace";
     sc.description = "<on | off> - Turns the OS trace on or off.";
     sc.function = shellTrace;
     this.commandList[this.commandList.length] = sc;
 
     // rot13 <string>
     sc = new ShellCommand();
     sc.command = "rot13";
     sc.description = "<string> - Does rot13 obfuscation on <string>.";
     sc.function = shellRot13;
     this.commandList[this.commandList.length] = sc;
 
     // prompt <string>
     sc = new ShellCommand();
     sc.command = "prompt";
     sc.description = "<string> - Sets the prompt.";
     sc.function = shellPrompt;
     this.commandList[this.commandList.length] = sc;
 
     // date
     sc = new ShellCommand();
     sc.command = "date";
     sc.description = "- Displays the current date and time."
     sc.function = shellDate;
     this.commandList[this.commandList.length] = sc;
 
     // whereami
     sc = new ShellCommand();
     sc.command = "whereami";
     sc.description = "- Displays where you are."
     sc.function = shellWhereami;
     this.commandList[this.commandList.length] = sc;
 
     // qwikerase
     sc = new ShellCommand();
     sc.command = "qwe";
     sc.description = "- QwikErase: Overrides all data in filesystem."
     sc.function = shellQuickerase;
     this.commandList[this.commandList.length] = sc;
 
     // status
     sc = new ShellCommand();
     sc.command = "status";
     sc.description = "- Sets the console's status.";
     sc.function = shellStatus;
     this.commandList[this.commandList.length] = sc;
 
     // load
     sc = new ShellCommand();
     sc.command = "load";
     sc.description = "- Loads an external program.";
     sc.function = shellLoad;
     this.commandList[this.commandList.length] = sc;
 
     // run
     sc = new ShellCommand();
     sc.command = "run";
     sc.description = "- Runs a process.";
     sc.function = shellRun;
     this.commandList[this.commandList.length] = sc;
 
     // runall
     sc = new ShellCommand();
     sc.command = "runall";
     sc.description = "- Runs all resident processes.";
     sc.function = shellRunAll;
     this.commandList[this.commandList.length] = sc;
 
     // reset
     sc = new ShellCommand();
     sc.command = "reset";
     sc.description = "- Resets the OS.";
     sc.function = shellReset;
     this.commandList[this.commandList.length] = sc;
 
     // rrquantum
     sc = new ShellCommand();
     sc.command = "rrquantum";
     sc.description = "- Sets the Round-Robin Quantum.";
     sc.function = shellRRQuantum;
     this.commandList[this.commandList.length] = sc;
 
     // processes
     sc = new ShellCommand();
     sc.command = "processes";
     sc.description = "- Shows all active processes' ID.";
     sc.function = shellProcesses;
     this.commandList[this.commandList.length] = sc;
 
     // kill 
     sc = new ShellCommand();
     sc.command = "kill";
     sc.description = "- Kills the specified process ID.";
     sc.function = shellKill;
     this.commandList[this.commandList.length] = sc;
 
     // change directory 
     sc = new ShellCommand();
     sc.command = "cd";
     sc.description = "- Changes the current working directory.";
     sc.function = shellCD;
     this.commandList[this.commandList.length] = sc;
 
     // create directory 
     sc = new ShellCommand();
     sc.command = "mkdir";
     sc.description = "- Creates a new directory in the current directory.";
     sc.function = shellCreateDirectory;
     this.commandList[this.commandList.length] = sc;
 
     // create text file 
     sc = new ShellCommand();
     sc.command = "create";
     sc.description = "- Creates a new text file in the current directory.";
     sc.function = shellCreateFile;
     this.commandList[this.commandList.length] = sc;
 
     // read 
     sc = new ShellCommand();
     sc.command = "read";
     sc.description = "- Reads a file in the filesystem.";
     sc.function = shellRead;
     this.commandList[this.commandList.length] = sc;
 
     // write 
     sc = new ShellCommand();
     sc.command = "write";
     sc.description = "- Writes text to file in the filesystem.";
     sc.function = shellWrite;
     this.commandList[this.commandList.length] = sc;
 
     // delete 
     sc = new ShellCommand();
     sc.command = "delete";
     sc.description = "- Deletes a file in the filesystem.";
     sc.function = shellDelete;
     this.commandList[this.commandList.length] = sc;
 
     // format 
     sc = new ShellCommand();
     sc.command = "format";
     sc.description = "- Formats entire filesystem.";
     sc.function = shellFormat;
     this.commandList[this.commandList.length] = sc;
 
     // ls 
     sc = new ShellCommand();
     sc.command = "ls";
     sc.description = "- Lists the files currently stored on disk.";
     sc.function = shellLs;
     this.commandList[this.commandList.length] = sc;
 
     // setcpu 
     sc = new ShellCommand();
     sc.command = "setcpu";
     sc.description = "- Set cpu scheduling to rr, fcfs or priority.";
     sc.function = shellSetcpu;
     this.commandList[this.commandList.length] = sc;
 
     // whatcpu 
     sc = new ShellCommand();
     sc.command = "whatcpu";
     sc.description = "- Shows the currently running cpu schedule.";
     sc.function = shellWhatcpu;
     this.commandList[this.commandList.length] = sc;
 
     //
     // Display the initial prompt.
     this.putPrompt();
 }
 
 function shellPutPrompt()
 {
     _StdIn.putText(this.promptStr);
 }
 
 function shellHandleInput(buffer)
 {
     krnTrace("Shell Command~" + buffer);
     // 
     // Parse the input...
     //
     var userCommand = new UserCommand();
     userCommand = shellParseInput(buffer);
     // ... and assign the command and args to local variables.
     var cmd = userCommand.command;
     var args = userCommand.args;
     //
     // Determine the command and execute it.
     //
     // Javascript may not support associative arrays (one of the few nice features of PHP, actually)
     // so we have to iterate over the command list in attempt to find a match.  TODO: Is there a better way?
     var index = 0;
     var found = false;
     while (!found && index < this.commandList.length)
     {
         if (this.commandList[index].command === cmd)
         {
             found = true;
             fn = this.commandList[index].function;
         }
         else
         {
             ++index;
         }
     }
     if (found)
     {
         this.execute(fn, args);
     }
     else
     {
         // It's not found, so check for curses and apologies before declaring the command invalid.
         if (this.curses.indexOf("[" + rot13(cmd) + "]") >= 0)      // Check for curses.
         {
             this.execute(shellCurse);
         }
         else if (this.apologies.indexOf("[" + cmd + "]") >= 0)      // Check for apoligies.
         {
             this.execute(shellApology);
         }
         else if(cmd == "") 
         {
            _StdIn.advanceLine();
            _StdIn.putText(this.promptStr);
         }
         else    // It's just a bad command.
         {
             this.execute(shellInvalidCommand);
         }
     }
 }
 
 
 function shellParseInput(buffer)
 {
     var retVal = new UserCommand();
     //
     // 1. Remove leading and trailing spaces.
     buffer = trim(buffer);
     // 2. Lower-case it.
     buffer = buffer.toLowerCase();
     // 3. Separate on spaces so we can determine the command and command-line args, if any.
     var tempList = buffer.split(" ");
     // 4. Take the first (zeroth) element and use that as the command.
     var cmd = tempList.shift();  // Yes, you can do that to an array in Javascript.  See the Queue class.
     // 4.1 Remove any left-over spaces.
     cmd = trim(cmd);
     // 4.2 Record it in the return value.
     retVal.command = cmd;
     //
     // 5. Now create the args array from what's left.
     for (var i in tempList)
     {
         var arg = trim(tempList[i]);
         if (arg != "")
         {
             retVal.args[retVal.args.length] = tempList[i];
         }
     }
     return retVal;
 }
 
 
 function shellExecute(fn, args)
 {
     // we just got a command, so advance the line... 
     _StdIn.advanceLine();
     // .. call the command function passing in the args...
     fn(args);
     // Check to see if we need to advance the line again
     if (_StdIn.CurrentXPosition > 0)
     {
         _StdIn.advanceLine();
     }
     // ... and finally write the prompt again.
     this.putPrompt();
 }
 
 
 //
 // The rest of these functions ARE NOT part of the Shell "class" (prototype, more accurately), 
 // as they are not denoted in the constructor.  The idea is that you cannot execute them from
 // elsewhere as shell.xxx .  In a better world, and a more perfect Javascript, we'd be 
 // able to make then private.  (Actually, we can. Someone look at Crockford's stuff and give me the details, please.)
 //
 
 //
 // An "interior" or "private" class (prototype) used only inside Shell() (we hope).
 //
 function ShellCommand()     
 {
     // Properties
     this.command = "";
     this.description = "";
     this.function = "";
 }
 
 //
 // Another "interior" or "private" class (prototype) used only inside Shell() (we hope).
 //
 function UserCommand()
 {
     // Properties
     this.command = "";
     this.args = [];
 }
 
 
 //
 // Shell Command Functions.  Again, not part of Shell() class per se', just called from there.
 //
 function shellInvalidCommand()
 {
     _StdIn.putText("Invalid Command. ");
     if (_SarcasticMode)
     {
         _StdIn.putText("Duh. Go back to your Speak & Spell.");
     }
     else
     {
         _StdIn.putText("Type 'help' for, well... help.");
     }
 }
 
 function shellCurse()
 {
     _StdIn.putText("Oh, so that's how it's going to be, eh? Fine.");
     _StdIn.advanceLine();
     _StdIn.putText("Bitch.");
     _SarcasticMode = true;
 }
 
 function shellApology()
 {
     _StdIn.putText("Okay. I forgive you. This time.");
     _SarcasticMode = false;
 }
 
 function shellVer(args)
 {
     _StdIn.putText(APP_NAME + " v." + APP_VERSION);    
 }
 
 function shellHelp(args)
 {
     _StdIn.putText("Commands:");
     for (i in _OsShell.commandList)
     {
         _StdIn.advanceLine();
         _StdIn.putText("  " + _OsShell.commandList[i].command + " " + _OsShell.commandList[i].description);
     }    
 }
 
 function shellShutdown(args)
 {
      _StdIn.putText("Shutting down...");
      // Call Kernal shutdown routine.
     krnShutdown();   
     // TODO: Stop the final prompt from being displayed.  If possible.  Not a high priority.  (Damn OCD!)
 }
 
 function shellCls(args)
 {
     _StdIn.clearScreen();
     _StdIn.resetXY();
     _StdIn.resetScroll();
 }
 
 function shellMan(args)
 {
     if (args.length > 0)
     {
         var topic = args[0];
         switch (topic)
         {
             case "help": 
                 _StdIn.putText("Help displays a list of (hopefully) valid commands.");
                 break;
             default:
                 _StdIn.putText("No manual entry for " + args[0] + ".");
         }        
     }
     else
     {
         _StdIn.putText("Usage: man <topic>  Please supply a topic.");
     }
 }
 
 function shellTrace(args)
 {
     if (args.length > 0)
     {
         var setting = args[0];
         switch (setting)
         {
             case "on": 
                 if (_Trace && _SarcasticMode)
                 {
                     _StdIn.putText("Trace is already on, dumbass.");
                 }
                 else
                 {
                     _Trace = true;
                     _StdIn.putText("Trace ON");
                 }
                 
                 break;
             case "off": 
                 _Trace = false;
                 _StdIn.putText("Trace OFF");                
                 break;                
             default:
                 _StdIn.putText("Invalid arguement.  Usage: trace <on | off>.");
         }        
     }
     else
     {
         _StdIn.putText("Usage: trace <on | off>");
     }
 }
 
 function shellRot13(args)
 {
     if (args.length > 0)
     {
         _StdIn.putText(args[0] + " = '" + rot13(args[0]) +"'");     // Requires Utils.js for rot13() function.
     }
     else
     {
         _StdIn.putText("Usage: rot13 <string>  Please supply a string.");
     }
 }
 
 function shellPrompt(args)
 {
     if (args.length > 0)
     {
         _OsShell.promptStr = args[0];
     }
     else
     {
         _StdIn.putText("Usage: prompt <string>  Please supply a string.");
     }
 }
 
 /*
  * Displays the current date and time in the format: "MM/DD/YYYY HH:MM:SS"
  */
 function shellDate(args)
 {
     _StdIn.putText(Date());   
 }
 
 /*
  * Displays where you are.
  */
 function shellWhereami(args) {
   if (navigator.geolocation) {
     navigator.geolocation.getCurrentPosition(
       function (position) {
         _StdIn.putText('lat:' + position.coords.latitude + ' lng:' + position.coords.longitude);
       }.bind(this),
       function () {}.bind(this)); //failure
   } else {
     _StdIn.putText("Geolocation not found.");
   }
   return false;
 }
 
 // TODO: Override all data in filesystem less than 2 seconds
 // (when the filesystem is implemented).
 function shellQuickerase(args) 
 { 
     _Console.gsod();
 }
 
 /* 
  * Sets the status of the status.
  */
 function shellStatus(args)
 {
     if (args.length > 0)
     {
         var status = args.join(" ");  
         _Console.taskbarSetStatus(status);
         _Console.taskbarRefresh();
     }
     else
     {
         _StdOut.putText("Usage: status <string>  Please supply a status.");
     }
 }
 
 /*
  * Loads a program into a memory so it becomes a process.
  */
 function shellLoad(args)  {
 
   function getPriority() {
     var priority = args[0];
     if(priority == undefined || 
        !isInt(priority) || 
        CPU_STATE != CPU_STATE_PRIORITY.name) { 
 
       if(CPU_STATE != CPU_STATE_PRIORITY.name &&
          priority != undefined && 
          isInt(priority)) {
         _StdOut.putText("Scheduler not set to Priority.");
         _Console.advanceLine();
       }
 
       return 5;
     } else 
       return priority;
   }
 
   var hex = trim(document.getElementById(TA_PROGRAM_INPUT).
       value.replace(/\n/g, " "));
 
   if(isValidHex(hex)) { // in utils.js
     var bytes = hex.split(" ");
     if(bytes.length > 1) {
       if (bytes.length <= MAX_MEMORY_PROGRAM) {
         // pass the hex to kernel's memory manager
         var priority = getPriority();
         var pid = _KernelMemoryManager.load(bytes, priority);
         if(pid < 0)
           _StdOut.putText("There is no memory available.");
         else 
           _StdOut.putText("Your program has been "+
               "successfully loaded with PID: " + pid);
       } else {
         _StdOut.putText("Program is too large. Must be"+
             " less than "+MAX_MEMORY_PROGRAM+" bytes.");
       }
     } else _StdOut.putText("Input Program textarea is empty."); 
   } else {
     _StdOut.putText("Invalid program. Make sure it's"+
         " properly formatted hex.");
   }
 }
 
 /*
  * Executes a loaded process given a PID. 
  */
 function shellRun(args)  {
   var pid = args[0];
   if(pid == undefined) {
     _StdIn.putText('Usage: run <pid>');
   } else {
     var process = _KernelMemoryManager.processes[pid];
     if(process == undefined) {
       _StdOut.putText("No such process.");
     } else {
       if(process.state != PCB_STATE_RESIDENT)
         _StdOut.putText("Process cannot run.");
       else {
         _KernelReadyQueue.push(process, process.priority);
         process.setState(PCB_STATE_READY);
       }
     }
   }
 }
 
 /*
  * Runs all resident processes.
  */
 function shellRunAll(args) {
   var ps = _KernelMemoryManager.processes;
   var ran = 0;
   for(var i=0; i<ps.length; i++) {
     if(ps[i].state == PCB_STATE_RESIDENT) {
       _KernelReadyQueue.push(ps[i], ps[i].priority);
       ps[i].setState(PCB_STATE_READY);
       ran++;
     }
   }
   _StdOut.putText("Running "+ran+" processes.");
 }
 
 /*
  * Resets the entire operating system.
  */
 function shellReset(args) {
   simBtnReset_click(null);
 }
 
 /*
  * Sets the Round-Robin quantum.
  */
 function shellRRQuantum(args) {
   var newQuantum = args[0];
   if(newQuantum == undefined) {
     _StdOut.putText("Usage: rrquantum <quantum number>");
     _Console.advanceLine();
     _StdOut.putText("Current Quantum: "+RR_QUANTUM);
   } else if(!isInt(newQuantum.trim()))
     _StdOut.putText("Invalid quantum value.");
   else {
     RR_QUANTUM = newQuantum.trim();
     _StdOut.putText("Round-Robin Quantum set to "+RR_QUANTUM);
   }
 }
 
 /*
  * Shows all active processes' ID.
  */
 function shellProcesses(args) {
   var ps = _KernelMemoryManager.processes;
   _StdOut.putText("Total Active PIDs: "+ps.length);
   _Console.advanceLine();
   for(var i=0; i<ps.length; i++) {
     _StdOut.putText(ps[i].PID+" - "+ps[i].state);
     _Console.advanceLine();
   }
 }
 
 /*
  * Kills an active process in ready, resident 
  * or running mode.
  */
 function shellKill(args) {
   var pid = args[0];
   if(pid == undefined) {
     _StdIn.putText('Usage: kill <pid>');
   } else {
     var process = _KernelMemoryManager.processes[pid];
     if(process == undefined) {
       _StdOut.putText("No such process.");
     } else {
       if(process.state == PCB_STATE_TERMINATED)
         _StdOut.putText("Process is already terminated.");
       else {
         process.setState(PCB_STATE_TERMINATED);
       }
     }
   }
 }
 
 /*
  * Changes the current working directory.
  */
 function shellCD(args) {
   var fn = args[0];
 
   if(fn == undefined) {
     _StdOut.putText("Usage: cd <directory name>");
     return;
   }
 
   if(!krnFilesystemDriver.changeDirectory(fn))
     _StdOut.putText(fn+" is not a directory");
 }
 
 /*
  * Creates a new directory.
  */
 function shellCreateDirectory(args) {
   var fn = args[0];
 
   if(fn == undefined) {
     _StdOut.putText("Usage: mkdir <file name>");
     return;
   }
 
   if(krnFilesystemDriver.createDirectory(fn))
     _StdOut.putText(fn+" created");
   else 
     _StdOut.putText(fn+" not created");
 }
 
 /*
  * Creates a new text file.
  */
 function shellCreateFile(args) {
   var fn = args[0];
 
   if(fn == undefined) {
     _StdOut.putText("Usage: create <file name>");
     return;
   }
 
   if(krnFilesystemDriver.createTextFile(fn))
     _StdOut.putText(fn+" created");
   else 
     _StdOut.putText(fn+" not created");
 }
 
 /*
  * Reads a file.
  */
 function shellRead(args) {
   var fn = args[0];
 
   if(fn == undefined) {
     _StdOut.putText("Usage: read <file name>");
     return;
   }
 
   var text = krnFilesystemDriver.readTextFile(fn);
   if(text == undefined) 
     _StdOut.putText(fn+" is not a text file.");
   else {
     _StdOut.putText(text);
   }
 }
 
 /*
  * Writes data to a file.
  */
 function shellWrite(args) {
   var fn = args[0];
   var data = args[1];
   for(var i=2; i<args.length; i++)
     data += " "+args[i];
 
   if(fn == undefined || data == undefined) {
     _StdOut.putText("Usage: write <file name> <data>");
     return;
   }
   
   if(krnFilesystemDriver.writeTextFile(fn,data))
     _StdOut.putText(fn+" modified");
   else 
     _StdOut.putText(fn+" not modified");
 }
 
 /*
  * Deletes a file.
  */
 function shellDelete(args) {
   var fn = args[0];
 
   if(fn == undefined) {
     _StdOut.putText("Usage: delete <file name>");
     return;
   }
 
   if(krnFilesystemDriver.deleteFile(fn))
     _StdOut.putText(fn+" deleted");
   else 
     _StdOut.putText(fn+" not deleted");
 }
 
 /*
  * Formats the entire filesystem.
  */
 function shellFormat(args) {
   if(krnFilesystemDriver.format())
     _StdOut.putText("Format succeeded");
   else 
     _StdOut.putText("Format FAILED");
 }
 
 /*
  * Lists the files currently stored on disk.
  */
 function shellLs(args) {
   var files = krnFilesystemDriver.ls();
   for(var i=0; i < files.length; i++) {
     var file = files[i];
     var name = file.name();
     var type = file.type();
     var type_dir = file.TYPE_DIR;
 
     if(type == type_dir)
       _StdOut.putText("d - "+name);
     else
       _StdOut.putText("t - "+name);
 
     _Console.advanceLine();
   }
 }
 
 /*
  * Set cpu scheduling to rr, fcfs or priority.
  */
 function shellSetcpu(args) {
   function setScheduler(schedule) {
     var running = _KernelCPUScheduler.running;
     if(!running || running.state != PCB_STATE_RUNNING) {
       CPU_STATE = schedule;
       _StdOut.putText("CPU Scheduler set to "+schedule);
     } else
       _StdOut.putText("CPU Scheduler is running.");
   }
 
   var scheduling = args[0];
 
   if(scheduling == undefined)
     _StdOut.putText("Usage: setcpu <scheduler (rr, fcfs, priority)>");
   else {
     scheduling = scheduling.trim().toLowerCase();
     if(CPU_STATE_RR.abbr == scheduling) 
       setScheduler(CPU_STATE_RR.name);
     else if(CPU_STATE_FCFS.abbr == scheduling)
       setScheduler(CPU_STATE_FCFS.name);
     else if(CPU_STATE_PRIORITY.abbr == scheduling)
       setScheduler(CPU_STATE_PRIORITY.name);
     else 
       _StdOut.putText("Invalid. Values: rr, fcfs, priority");
   }
 }
 
 /*
  * Shows the currently running cpu scheduling.
  */
 function shellWhatcpu(args) {
   _StdOut.putText("CPU Scheduler set to "+CPU_STATE);
 }