Add Syscall: Exit, PutChar, GetCar, PutString, GetString

code/threads/main.cc

@@ -18,7 +18,6 @@
 
 #include "utility.h"
 #include "system.h"
-
 #ifdef USER_PROGRAM
 #include "progtest.h"
 #endif
@@ -118,6 +117,7 @@ main (int argc, char **argv)
 	  if (!strcmp (*argv, "-x"))
 	    {			// run a user program
 		ASSERT (argc > 1);
+        consoledriver = new ConsoleDriver(NULL,NULL);
 		StartProcess (*(argv + 1));
 		argCount = 2;
 	    }
@@ -132,6 +132,19 @@ main (int argc, char **argv)
 		      argCount = 3;
 		  }
 	    }
+#ifdef CHANGED
+      else if (!strcmp (*argv, "-sc"))
+        {           // test the consoledriver
+    	if (argc == 1)
+	      ConsoleDriverTest (NULL, NULL);
+	    else
+	     {
+           ASSERT (argc > 2);
+	       ConsoleDriverTest (*(argv + 1), *(argv + 2));
+	       argCount = 3;
+	     }
+	   }
+#endif // CHANGE
 #endif // USER_PROGRAM
 #ifdef FILESYS
 	  if (!strcmp (*argv, "-cp"))

code/threads/system.cc

@@ -33,7 +33,12 @@ SynchDisk *synchDisk;
 
 #ifdef USER_PROGRAM		// requires either FILESYS or FILESYS_STUB
 Machine *machine;		// user program memory and registers
-#endif
+
+#ifdef CHANGED // Define our consoledriver Object
+ConsoleDriver *consoledriver;
+#endif // CHANGED
+
+#endif // USER_PROGRAM
 
 #ifdef NETWORK
 PostOffice *postOffice;
@@ -230,6 +235,12 @@ Cleanup ()
 	delete machine;
 	machine = NULL;
     }
+#ifdef CHANGED
+    if (consoledriver) {
+        delete consoledriver;
+        consoledriver = NULL;
+    }
+#endif
 #endif
 
 #ifdef FILESYS_NEEDED

code/threads/system.h

@@ -32,6 +32,13 @@ extern Timer *timer;		// the hardware alarm clock
 #ifdef USER_PROGRAM
 #include "machine.h"
 extern Machine *machine;	// user program memory and registers
+
+#ifdef CHANGED
+#define MAX_STRING_SIZE 8
+#include "consoledriver.h"
+extern ConsoleDriver *consoledriver; // add console driver
+#endif
+
 #endif
 
 #ifdef FILESYS_NEEDED		// FILESYS or FILESYS_STUB