libiberty/hex.c

   1 /* Hex character manipulation support.
   2    Copyright (C) 1995, 2001 Free Software Foundation, Inc.
   3
   4 This file is part of the libiberty library.
   5 Libiberty is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public
   7 License as published by the Free Software Foundation; either
   8 version 2 of the License, or (at your option) any later version.
   9
  10 Libiberty is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with libiberty; see the file COPYING.LIB.  If
  17 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18 Boston, MA 02111-1307, USA.  */
  19
  20 #include <stdio.h>  /* for EOF */
  21 #include "libiberty.h"
  22
  23 /*
  24
  25 @deftypefn Extension void hex_init (void)
  26
  27 Initializes the array mapping the current character set to
  28 corresponding hex values.  This function must be called before any
  29 call to @code{hex_p} or @code{hex_value}.  If you fail to call it, a
  30 default ASCII-based table will normally be used on ASCII systems.
  31
  32 @end deftypefn
  33
  34 @deftypefn Extension int hex_p (int @var{c})
  35
  36 Evaluates to non-zero if the given character is a valid hex character,
  37 or zero if it is not.  Note that the value you pass will be cast to
  38 @code{unsigned char} within the macro.
  39
  40 @end deftypefn
  41
  42 @deftypefn Extension unsigned int hex_value (int @var{c})
  43
  44 Returns the numeric equivalent of the given character when interpreted
  45 as a hexidecimal digit.  The result is undefined if you pass an
  46 invalid hex digit.  Note that the value you pass will be cast to
  47 @code{unsigned char} within the macro.
  48
  49 The @code{hex_value} macro returns @code{unsigned int}, rather than
  50 signed @code{int}, to make it easier to use in parsing addresses from
  51 hex dump files: a signed @code{int} would be sign-extended when
  52 converted to a wider unsigned type --- like @code{bfd_vma}, on some
  53 systems.
  54
  55 @end deftypefn
  56
  57 @undocumented _hex_array_size
  58 @undocumented _hex_bad
  59 @undocumented _hex_value
  60
  61 */
  62
  63
  64 /* Are we ASCII? */
  65 #if '\n' == 0x0A && ' ' == 0x20 && '0' == 0x30 \
  66   && 'A' == 0x41 && 'a' == 0x61 && '!' == 0x21 \
  67   && EOF == -1
  68
  69 const unsigned char _hex_value[_hex_array_size] =
  70 {
  71   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* NUL SOH STX ETX */
  72   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* EOT ENQ ACK BEL */
  73   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* BS  HT  LF  VT  */
  74   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* FF  CR  SO  SI  */
  75   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* DLE DC1 DC2 DC3 */
  76   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* DC4 NAK SYN ETB */
  77   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* CAN EM  SUB ESC */
  78   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* FS  GS  RS  US  */
  79
  80   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* SP  !   "   #   */
  81   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* $   %   &   '   */
  82   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* (   )   *   +   */
  83   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* ,   -   .   /   */
  84   0,        1,        2,        3,          /* 0   1   2   3   */
  85   4,        5,        6,        7,          /* 4   5   6   7   */
  86   8,        9,        _hex_bad, _hex_bad,   /* 8   9   :   ;   */
  87   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* <   =   >   ?   */
  88
  89   _hex_bad, 10,       11,       12,         /* @   A   B   C   */
  90   13,       14,       15,       _hex_bad,   /* D   E   F   G   */
  91   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* H   I   J   K   */
  92   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* L   M   N   O   */
  93   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* P   Q   R   S   */
  94   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* T   U   V   W   */
  95   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* X   Y   Z   [   */
  96   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* \   ]   ^   _   */
  97
  98   _hex_bad, 10,       11,       12,         /* `   a   b   c   */
  99   13,       14,       15,       _hex_bad,   /* d   e   f   g   */
 100   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* h   i   j   k   */
 101   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* l   m   n   o   */
 102   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* p   q   r   s   */
 103   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* t   u   v   w   */
 104   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* x   y   z   {   */
 105   _hex_bad, _hex_bad, _hex_bad, _hex_bad,   /* |   }   ~   DEL */
 106
 107   /* The high half of unsigned char, all values are _hex_bad.  */
 108   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 109   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 110   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 111   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 112   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 113   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 114   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 115   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 116
 117   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 118   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 119   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 120   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 121   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 122   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 123   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 124   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 125
 126   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 127   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 128   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 129   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 130   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 131   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 132   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 133   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 134
 135   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 136   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 137   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 138   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 139   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 140   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 141   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 142   _hex_bad, _hex_bad, _hex_bad, _hex_bad,
 143 };
 144 #define HEX_TABLE_INITIALIZED
 145
 146 #else
 147
 148 unsigned char _hex_value[_hex_array_size];
 149
 150 #endif /* not ASCII */
 151
 152 void
 153 hex_init ()
 154 {
 155 #ifndef HEX_TABLE_INITIALIZED
 156   int i;
 157
 158   for (i=0; i<_hex_array_size; i++)
 159     {
 160       switch (i)
 161         {
 162         case '0': _hex_value[i] = 0; break;
 163         case '1': _hex_value[i] = 1; break;
 164         case '2': _hex_value[i] = 2; break;
 165         case '3': _hex_value[i] = 3; break;
 166         case '4': _hex_value[i] = 4; break;
 167         case '5': _hex_value[i] = 5; break;
 168         case '6': _hex_value[i] = 6; break;
 169         case '7': _hex_value[i] = 7; break;
 170         case '8': _hex_value[i] = 8; break;
 171         case '9': _hex_value[i] = 9; break;
 172
 173         case 'a': case 'A': _hex_value[i] = 10; break;
 174         case 'b': case 'B': _hex_value[i] = 11; break;
 175         case 'c': case 'C': _hex_value[i] = 12; break;
 176         case 'd': case 'D': _hex_value[i] = 13; break;
 177         case 'e': case 'E': _hex_value[i] = 14; break;
 178         case 'f': case 'F': _hex_value[i] = 15; break;
 179
 180         default:
 181           _hex_value[i] = _hex_bad;
 182           break;
 183         }
 184     }
 185 #endif
 186 }