/*----------------------------------------------------*/
/* qpencode.c --   QuotedPrintable-Encoding Filter    */
/*----------------------------------------------------*/
/*  Usage:                                            */
/*    qpencode [infile] > <file>                      */
/*        infile: filename of the file to be encoded  */
/*                (if omitted, input from stdin)      */
/*     result(stdout) should be redirected to <file>  */
/*----------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>

int main(int argc, char *argv[])
{ int c, b='\0', n=0;
  FILE *fp;
# ifdef O_BINARY
  setmode(1,O_BINARY);
# endif
  if (argc == 1) {
    fp = stdin;
# ifdef O_BINARY
    setmode(0,O_BINARY);
# endif
  } else if ((fp=fopen(argv[1],"rb")) == NULL) {
    fprintf(stderr, "file %s not found\n", argv[1]); exit(1);
  }
  while ((c=getc(fp)) != EOF) {
    if (c == 0x0D) {
      if ((c=getc(fp)) == EOF) { printf("=0D"); b = '\r'; n += 3; break; }
      if (c == 0x0A) {
        if (b == ' ') printf("=\r\n");
        printf("\r\n"); b = '\0'; n = 0;
      } else {
        ungetc(c, fp); printf("=0D"); b = '\r'; n += 3;
        if (n > 72) { printf("=\r\n"); b = '\0'; n = 0; }
      }
    } else if (c == 0x0A) {
      if (b == ' ') printf("=\r\n");
      printf("\r\n"); b = '\0'; n = 0;
    } else if ((c < 0x20) || (c == '=') || (c > 0x7E)) {
      printf("=%02X", c); n += 3; b = c;
      if (n > 72) { printf("=\r\n"); b = '\0'; n = 0; }
    } else {
      printf("%c", c); n++; b = c;
      if (n > 72) { printf("=\r\n"); b = '\0'; n = 0; }
    }
  }
  if (n != 0) printf("\r\n");
  fclose(fp); fclose(stdout);
  return(0);
}