string.h is ANSI C include file

[unix-history] / usr / src / usr.bin / uudecode / uudecode.c

/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
static char sccsid[] = "@(#)uudecode.c  5.9 (Berkeley) %G%";
#endif /* not lint */

/*
* uudecode [file ...]
*
* create the specified file, decoding as you go.
* used with uuencode.
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>

char *filename;

/* ARGSUSED */
main(argc, argv)
       int argc;
       char **argv;
{
       extern int errno;
       int rval;

       if (*++argv) {
               rval = 0;
               do {
                       if (!freopen(filename = *argv, "r", stdin)) {
                               (void)fprintf(stderr, "uudecode: %s: %s\n",
                                   *argv, strerror(errno));
                               rval = 1;
                               continue;
                       }
                       rval |= decode();
               } while (*++argv);
       } else {
               filename = "stdin";
               rval = decode();
       }
       exit(rval);
}

decode()
{
       extern int errno;
       struct passwd *pw;
       register int n;
       register char ch, *p;
       int mode, n1;
       char buf[MAXPATHLEN];

       /* search for header line */
       do {
               if (!fgets(buf, sizeof(buf), stdin)) {
                       (void)fprintf(stderr,
                           "uudecode: %s: no \"begin\" line\n", filename);
                       return(1);
               }
       } while (strncmp(buf, "begin ", 6));
       (void)sscanf(buf, "begin %o %s", &mode, buf);

       /* handle ~user/file format */
       if (buf[0] == '~') {
               if (!(p = index(buf, '/'))) {
                       (void)fprintf(stderr, "uudecode: %s: illegal ~user.\n",
                           filename);
                       return(1);
               }
               *p++ = NULL;
               if (!(pw = getpwnam(buf + 1))) {
                       (void)fprintf(stderr, "uudecode: %s: no user %s.\n",
                           filename, buf);
                       return(1);
               }
               n = strlen(pw->pw_dir);
               n1 = strlen(p);
               if (n + n1 + 2 > MAXPATHLEN) {
                       (void)fprintf(stderr, "uudecode: %s: path too long.\n",
                           filename);
                       return(1);
               }
               bcopy(p, buf + n + 1, n1 + 1);
               bcopy(pw->pw_dir, buf, n);
               buf[n] = '/';
       }

       /* create output file, set mode */
       if (!freopen(buf, "w", stdout) ||
           fchmod(fileno(stdout), mode&0666)) {
               (void)fprintf(stderr, "uudecode: %s: %s: %s\n", buf,
                   filename, strerror(errno));
               return(1);
       }

       /* for each input line */
       for (;;) {
               if (!fgets(p = buf, sizeof(buf), stdin)) {
                       (void)fprintf(stderr, "uudecode: %s: short file.\n",
                           filename);
                       return(1);
               }
#define DEC(c)  (((c) - ' ') & 077)             /* single character decode */
               /*
                * `n' is used to avoid writing out all the characters
                * at the end of the file.
                */
               if ((n = DEC(*p)) <= 0)
                       break;
               for (++p; n > 0; p += 4, n -= 3)
                       if (n >= 3) {
                               ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
                               putchar(ch);
                               ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
                               putchar(ch);
                               ch = DEC(p[2]) << 6 | DEC(p[3]);
                               putchar(ch);
                       }
                       else {
                               if (n >= 1) {
                                       ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
                                       putchar(ch);
                               }
                               if (n >= 2) {
                                       ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
                                       putchar(ch);
                               }
                               if (n >= 3) {
                                       ch = DEC(p[2]) << 6 | DEC(p[3]);
                                       putchar(ch);
                               }
                       }
       }
       if (!fgets(buf, sizeof(buf), stdin) || strcmp(buf, "end\n")) {
               (void)fprintf(stderr, "uudecode: %s: no \"end\" line.\n",
                   filename);
               return(1);
       }
       return(0);
}

usage()
{
       (void)fprintf(stderr, "usage: uudecode [file ...]\n");
       exit(1);
}