/*      $NetBSD: subr_optstr.c,v 1.8 2023/04/20 09:04:45 skrll Exp $    */

/*-
* Copyright (c) 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Julio M. Merino Vidal.
*
* 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.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: subr_optstr.c,v 1.8 2023/04/20 09:04:45 skrll Exp $");

#include <sys/param.h>
#include <sys/optstr.h>

/* --------------------------------------------------------------------- */

/*
* Given an options string of the form 'a=b c=d ... y=z' and a key,
* looks for the given key's value in the string and returns it in buf
* with a maximum of bufsize bytes.  If the key is found, returns true;
* otherwise FALSE.
*/


static bool
optstr_get_pointer(const char *optstr, const char *key, const char **result)
{
       bool found = false;

       /* Skip any initial spaces or tabs until we find a word. */
       while (*optstr == ' ' || *optstr == '\t')
               optstr++;

       /* Search for the given key within the option string. */
       while (!found && *optstr != '\0') {
               const char *keyp;

               /* Check if the next word matches the key. */
               keyp = key;
               while (*optstr == *keyp) {
                       optstr++;
                       keyp++;
               }

               if (*optstr == '=' && *keyp == '\0')
                       found = true;
               else {
                       /* Key not found; skip until next space. */
                       while (*optstr != ' ' && *optstr != '\0')
                               optstr++;

                       /* And now skip until next word. */
                       while (*optstr == ' ')
                               optstr++;
               }
       }

       if (found) {
               optstr++; /* Skip '='. */
               *result = optstr;
       }

       return found;
}

bool
optstr_get(const char *optstr, const char *key, char *buf, size_t bufsize)
{
       const char *data;
       bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               const char *lastbuf = buf + (bufsize - 1);

               while (buf != lastbuf && *data != ' ' && *data != '\0')
                       *buf++ = *data++;
               *buf = '\0';
       }
       return found;
}


bool
optstr_get_string(const char *optstr, const char *key, const char **result)
{
       const char *data;
       const bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               *result = data;
       }
       return found;
}

bool
optstr_get_number(const char *optstr, const char *key, unsigned long *result)
{
       const char *data;
       const bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               char *ep;
               const unsigned long ulval = strtoul(data, &ep, 10);
               if (ep == data)
                       return false;
               *result = ulval;
               return true;
       }
       return false;
}

bool
optstr_get_number_hex(const char *optstr, const char *key,
   unsigned long *result)
{
       const char *data;
       const bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               char *ep;
               const unsigned long ulval = strtoul(data, &ep, 16);
               if (ep == data)
                       return false;
               *result = ulval;
               return true;
       }
       return false;
}

bool
optstr_get_number_binary(const char *optstr, const char *key,
   unsigned long *result)
{
       const char *data;
       const bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               char *ep;
               const unsigned long ulval = strtoul(data, &ep, 2);
               if (ep == data)
                       return false;
               *result = ulval;
               return true;
       }
       return false;
}


#if NETHER > 0
bool
optstr_get_macaddr(const char *optstr, const char *key,
   uint8_t result[ETHER_ADDR_LEN])
{
       const char *data;
       const bool found = optstr_get_pointer(optstr, key, &data);

       /* If the key was found; copy its value to the target buffer. */
       if (found) {
               uint8_t temp[ETHER_ADDR_LEN];
               int error = ether_aton_r(temp, sizeof(temp), data);
               if (error)
                       return false;
               memcpy(result, temp, sizeof(temp));
       }
       return found;
}
#endif