console.h

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#ifndef CONSOLE_H
#define CONSOLE_H

#include "copyright.h"
#include "utility.h"


class Console {
  public:
    Console(char *readFile, char *writeFile, VoidFunctionPtr readAvail, 
    VoidFunctionPtr writeDone, int callArg);
                // initialize the hardware console device
    ~Console();         // clean up console emulation

// external interface -- Nachos kernel code can call these
    void PutChar(char ch);  // Write "ch" to the console display, 
                // and return immediately.  "writeHandler" 
                // is called when the I/O completes. 

    char GetChar();     // Poll the console input.  If a char is 
                // available, return it.  Otherwise, return EOF.
                    // "readHandler" is called whenever there is 
                // a char to be gotten

// internal emulation routines -- DO NOT call these. 
    void WriteDone();       // internal routines to signal I/O completion
    void CheckCharAvail();
     // Retrurn true if EndOfFile(nothing to read there)
    bool Feof();

  private:
    int readFileNo;         // UNIX file emulating the keyboard 
    int writeFileNo;            // UNIX file emulating the display
    VoidFunctionPtr writeHandler;   // Interrupt handler to call when 
                    // the PutChar I/O completes
    VoidFunctionPtr readHandler;    // Interrupt handler to call when 
                    // a character arrives from the keyboard
    int handlerArg;         // argument to be passed to the 
                    // interrupt handlers
    bool putBusy;               // Is a PutChar operation in progress?
                    // If so, you can't do another one!
    char incoming;              // Contains the character to be read,
                    // if there is one available. 
                    // Otherwise contains EOF.

   
};

#endif // CONSOLE_H