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

code/userprog/consoledriver.cc

@@ -0,0 +1,66 @@
+#ifdef CHANGED
+#include "copyright.h"
+#include "system.h"
+#include "consoledriver.h"
+#include "synch.h"
+
+#define STRINGBUFFER 8 
+
+static Semaphore *readAvail;
+static Semaphore *writeDone;
+
+static void ReadAvailHandler(void *arg) { (void) arg; readAvail->V(); }
+static void WriteDoneHandler(void *arg) { (void) arg; writeDone->V(); }
+
+ConsoleDriver::ConsoleDriver(const char *in, const char *out)
+{
+  readAvail = new Semaphore("read avail", 0);
+  writeDone = new Semaphore("write done", 0);
+  console = new Console (in, out, ReadAvailHandler, WriteDoneHandler, NULL);
+}
+
+ConsoleDriver::~ConsoleDriver()
+{
+  delete console;
+  delete writeDone;
+  delete readAvail;
+}
+
+void ConsoleDriver::PutChar( int ch)
+{
+    console->TX(ch);
+	writeDone->P();	
+}
+
+int ConsoleDriver::GetChar()
+{
+	readAvail->P();
+	int ch = console->RX();
+	return ch;
+}
+
+void ConsoleDriver::PutString(const char s[MAX_STRING_SIZE])
+{
+  int i;
+  for (i = 0; i < MAX_STRING_SIZE; i++){
+    if (*(s+i) =='\0'){
+      return;
+    }
+    PutChar(*(s+i));
+  }
+}
+
+void ConsoleDriver::GetString(char * s, int n)
+{
+  int i;
+  for ( i = 0; i < n - 1; i++){
+    char c = GetChar();
+    if ( c == '\0' || c == '\n' || c == EOF) {
+      break;
+    }
+    *(s+i) =  c;
+  }
+  *(s+i) = '\0'; 
+}
+
+#endif // CHANGED