filehdr.h

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#include "copyright.h"

#ifndef FILEHDR_H
#define FILEHDR_H

#include "disk.h"
#include "bitmap.h"

#define NumDirect    ((SectorSize - 2 * sizeof(int)) / sizeof(int))
#define MaxFileSize    (NumDirect * SectorSize)

enum File_type {
    f, // file type
    d // directory type
};


class FileHeader {
public:
    bool Allocate(BitMap *bitMap, int fileSize);// Initialize a file header, 
    //  including allocating space
    //  on disk for the file data
    void Deallocate(BitMap *bitMap);        // De-allocate this file's
    //  data blocks

    void FetchFrom(int sectorNumber);    // Initialize file header from disk
    void WriteBack(int sectorNumber);    // Write modifications to file header
    //  back to disk

    int ByteToSector(int offset);    // Convert a byte offset into the file
    // to the disk sector containing
    // the byte

    int FileLength();            // Return the length of the file in bytes

    void Print();            // Print the contents of the file.

    File_type type;

    void test();

    int get_sector(int id_sector);

    void set_sector(int id_sector, int sector);

private:
    int numBytes;            // Number of bytes in the file
    int numSectors;            // Number of data sectors in the file
    int dataSectors[NumDirect];        // Disk sector numbers for each data block in the file

};

#endif // FILEHDR_H