mdw@git.distorted.org.uk Git - userv-utils/blob - ipif/hex.c

   1 /*
   2  * Copyright (C) 1997,2000,2003 Ian Jackson
   3  * This file is part of ipif, part of userv-utils
   4  *
   5  * This is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with userv-utils; if not, write to the Free Software
  17  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <assert.h>
  23 #include <string.h>
  24 #include <sysexits.h>
  25
  26 #include "hex.h"
  27
  28 const char *tohex(uint8_t *data, int len, char *buf) {
  29   char *p;
  30
  31   for (p= buf;
  32        len>0;
  33        len--, data++, p+=2)
  34     sprintf(p,"%02x",*data);
  35   return buf;
  36 }
  37
  38 void unhex(const char *what, const char *txt, uint8_t *datar, int *lenr,
  39            int minlen, int maxlen) {
  40   int l, v;
  41   char buf[3], *ep;
  42
  43   l= strlen(txt);
  44   if (l%1) { fprintf(stderr,"odd number of hex digits in %s\n",what); exit(EX_DATAERR); }
  45   l>>=1;
  46   if (l<minlen) { fprintf(stderr,"too few hex digits in %s\n",what); exit(EX_DATAERR); }
  47   if (l>maxlen) { fprintf(stderr,"too many hex digits in %s\n",what); exit(EX_DATAERR); }
  48
  49   if (lenr) *lenr= l;
  50   while (l) {
  51     buf[0]= *txt++;
  52     buf[1]= *txt++;
  53     buf[2]= 0;
  54     v= strtoul(buf,&ep,16);
  55     if (*ep) { fprintf(stderr,"not hex digit in %s: %c\n",what,*ep); exit(EX_DATAERR); }
  56     *datar++= v;
  57     l--;
  58   }
  59 }