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nasb.cpp

#include <ctype.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>

#ifndef __GNUC__
#include <io.h>
#else
#include <unistd.h>
#endif

#include <swcomprs.h>

class FileCompress: public SWCompress {
        int ifd;
        int ofd;
        int ufd;
        int zfd;
public:
        FileCompress(char *);
        ~FileCompress();
        int GetChars(char *, int len);
        int SendChars(char *, int len);
        void Encode();
        void Decode();
};


FileCompress::FileCompress(char *fname) 
{
        char buf[256];

#ifndef O_BINARY
#define O_BINARY 0
#endif

        ufd  = open(fname, O_RDWR|O_CREAT|O_BINARY);

        sprintf(buf, "%s.zzz", fname);
        zfd = open(buf, O_RDWR|O_CREAT|O_BINARY);
}

        
FileCompress::~FileCompress(char *fname) 
{
        close(ufd);
        close(zfd);
}


int FileCompress::GetChars(char *buf, int len) 
{
        return read(ifd, buf, len);
}


int FileCompress::SendChars(char *buf, int len) 
{
        return write(ofd, buf, len);
}


void FileCompress::Encode() 
{
        ifd = ufd;
        ofd = zfd;

        SWCompress::Encode();
}


void FileCompress::Decode() 
{
        ifd = zfd;
        ofd = ufd;

        SWCompress::Decode();
}


main(int argc, char **argv)
{
        int decomp = 0;
        SWCompress *fobj;
        
        if (argc != 2) {
                fprintf(stderr, "usage: %s <filename|filename.zzz>\n", argv[0]);
                exit(1);
        }

        if (strlen(argv[1]) > 4) {
                if (!strcmp(&argv[1][strlen(argv[1])-4], ".zzz")) {
                        argv[1][strlen(argv[1])-4] = 0;
                        decomp = 1;
                }
        }
                        
        fobj = new FileCompress(argv[1]);
        
        if (decomp)
                fobj->Decode();
        else fobj->Encode();

        delete fobj;
}

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