/*      $NetBSD: strnvisx.c,v 1.1 2016/05/02 19:18:29 christos Exp $    */

/*-
* Copyright (c) 1998, 1999, 2004 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum; by Jason R. Thorpe of the Numerical Aerospace
* Simulation Facility, NASA Ames Research Center.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

/*
* from scsipiconf.c...
*/
#include <lib/libkern/libkern.h>

#define STRVIS_ISWHITE(x) ((x) == ' ' || (x) == '\0' || (x) == '\377')

int
strnvisx(char *dst, size_t dlen, const char *src, size_t slen, int flags)
{
       if (dlen == 0)
               return -1;

       if (flags & VIS_TRIM) {
               /* Trim leading and trailing blanks and NULs. */
               while (slen > 0 && STRVIS_ISWHITE(src[0]))
                       ++src, --slen;
               while (slen > 0 && STRVIS_ISWHITE(src[slen - 1]))
                       --slen;
       }

       while (slen > 0) {
               if ((flags & VIS_SAFE) && (*src < 0x20 || (*src & 0x80))) {
                       /* non-printable characters */
                       if (dlen < 4)
                               goto out;
                       dlen -= 4;
                       *dst++ = '\\';
                       *dst++ = ((*src & 0300) >> 6) + '0';
                       *dst++ = ((*src & 0070) >> 3) + '0';
                       *dst++ = ((*src & 0007) >> 0) + '0';
               } else if (*src == '\\') {
                       /* quote characters */
                       if (dlen < 2)
                               goto out;
                       dlen -= 2;
                       *dst++ = '\\';
                       *dst++ = '\\';
               } else {
                       /* normal characters */
                       if (dlen < 1)
                               goto out;
                       *dst++ = *src;
               }
               ++src, --slen;
       }
out:
       if (dlen > 0) {
               *dst++ = '\0';
               return slen ? -1 : 0;
       } else {
               *--dst = '\0';
               return -1;
       }
}