uuencode.c

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/* uuencode.c */

/*
uudecode and uuencode are easily implemented under MSDOS as well.  Here
are the sources for Microsoft C v3.0, but if you have another kind of C
compiler, there should be perhaps only 1 change -- the output file of
uudecode and the input file of uuencode must be in binary format.
(ie.  binary files, like .EXE files may have byte patterns that are the
same as ^Z, which signals end-of-file in non-binary (text) mode).

    Don Kneller
UUCP:   ...ucbvax!ucsfcgl!kneller
ARPA:   [e-mail]
BITNET: [e-mail]

   patched up for BC++ 3.1 by Alan Eldridge 10/12/92
       (UUCP: [e-mail], FIDO: 1:272/38.473)

*/

#ifndef lint
 #if !defined(MSDOS) && !defined(__MSDOS__)
 static char sccsid[] = "@(#)uuencode.c  5.1 (Berkeley) 7/2/83";
 #endif
#endif

#if defined(MSDOS) || defined(__MSDOS__)
 #define READ_BINARY "rb"
#else
 #define READ_BINARY "r"
#endif

/*
 * uuencode [input] output
 *
 * Encode a file so it can be mailed to a remote system.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>

/* ENC is the basic 1 character encoding function to make a char printing */

#define ENC(c) (((c) & 077) + ' ')

void encode(FILE *in, FILE *out);
void outdec(char *p, FILE *f);
int fr(FILE *fd, char *buf, int cnt);

main(int argc, char *argv[])
{
      FILE *in;
      struct stat sbuf;
      int mode;

      /* optional 1st argument */

      if (argc > 2)
      {
            /* Use binary mode */
            if ((in = fopen(argv[1], READ_BINARY)) == NULL)
            {
                  perror(argv[1]);
                  exit(1);
            }
            argv++; argc--;
      }
      else  in = stdin;

      if (argc != 2)
      {
            printf("Usage: uuencode [infile] remotefile\n");
            exit(2);
      }

      /* figure out the input file mode */

      fstat(fileno(in), &sbuf);
      mode = sbuf.st_mode & 0777;
      printf("begin %o %s\n", mode, argv[1]);

      encode(in, stdout);

      printf("end\n");
      return 0;
}

/*
 * copy from in to out, encoding as you go along.
 */

void encode(FILE *in, FILE *out)
{
      char buf[80];
      int i, n;

      for (;;)
      {
            /* 1 (up to) 45 character line */

            n = fr(in, buf, 45);
            putc(ENC(n), out);

            for (i = 0; i < n; i += 3)
                  outdec(&buf[i], out);

            putc('\n', out);
            if (n <= 0)
                  break;
      }
}

/*
 * output one group of 3 bytes, pointed at by p, on file f.
 */

void outdec(char *p, FILE *f)
{
      int c1, c2, c3, c4;

      c1 = *p >> 2;
      c2 = ((p[0] << 4) & 060) | ((p[1] >> 4) & 017);
      c3 = ((p[1] << 2) & 074) | ((p[2] >> 6) & 03);
      c4 = p[2] & 077;
      putc(ENC(c1), f);
      putc(ENC(c2), f);
      putc(ENC(c3), f);
      putc(ENC(c4), f);
}

/* fr: like read but stdio */

int fr(FILE *fd, char *buf, int cnt)
{
      int c, i;

      for (i = 0; i < cnt; i++)
      {
            c = getc(fd);
            if (c == EOF)
                  return(i);
            buf[i] = (char)c;
      }
      return (cnt);
}