src/libopts/streqvcmp.c

   1
   2 /**
   3  * \file streqvcmp.c
   4  *
   5  * Time-stamp:      "2012-03-31 13:17:39 bkorb"
   6  *
   7  *  String Equivalence Comparison
   8  *
   9  *  These routines allow any character to be mapped to any other
  10  *  character before comparison.  In processing long option names,
  11  *  the characters "-", "_" and "^" all need to be equivalent
  12  *  (because they are treated so by different development environments).
  13  *
  14  *  This file is part of AutoOpts, a companion to AutoGen.
  15  *  AutoOpts is free software.
  16  *  AutoOpts is Copyright (c) 1992-2012 by Bruce Korb - all rights reserved
  17  *
  18  *  AutoOpts is available under any one of two licenses.  The license
  19  *  in use must be one of these two and the choice is under the control
  20  *  of the user of the license.
  21  *
  22  *   The GNU Lesser General Public License, version 3 or later
  23  *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
  24  *
  25  *   The Modified Berkeley Software Distribution License
  26  *      See the file "COPYING.mbsd"
  27  *
  28  *  These files have the following md5sums:
  29  *
  30  *  43b91e8ca915626ed3818ffb1b71248b pkg/libopts/COPYING.gplv3
  31  *  06a1a2e4760c90ea5e1dad8dfaac4d39 pkg/libopts/COPYING.lgplv3
  32  *  66a5cedaf62c4b2637025f049f9b826f pkg/libopts/COPYING.mbsd
  33  *
  34  * This array is designed for mapping upper and lower case letter
  35  * together for a case independent comparison.  The mappings are
  36  * based upon ascii character sequences.
  37  */
  38 static unsigned char charmap[] = {
  39     NUL,  0x01, 0x02, 0x03,  0x04, 0x05, 0x06, '\a',
  40     '\b', '\t', NL,   '\v',  '\f', '\r', 0x0E, 0x0F,
  41     0x10, 0x11, 0x12, 0x13,  0x14, 0x15, 0x16, 0x17,
  42     0x18, 0x19, 0x1A, 0x1B,  0x1C, 0x1D, 0x1E, 0x1F,
  43
  44     ' ',  '!',  '"',  '#',   '$',  '%',  '&',  '\'',
  45     '(',  ')',  '*',  '+',   ',',  '-',  '.',  '/',
  46     '0',  '1',  '2',  '3',   '4',  '5',  '6',  '7',
  47     '8',  '9',  ':',  ';',   '<',  '=',  '>',  '?',
  48
  49     '@',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
  50     'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
  51     'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
  52     'x',  'y',  'z',  '[',   '\\', ']',  '^',  '_',
  53     '`',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
  54     'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
  55     'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
  56     'x',  'y',  'z',  '{',   '|',  '}',  '~',  0x7f,
  57
  58     0x80, 0x81, 0x82, 0x83,  0x84, 0x85, 0x86, 0x87,
  59     0x88, 0x89, 0x8A, 0x8B,  0x8C, 0x8D, 0x8E, 0x8F,
  60     0x90, 0x91, 0x92, 0x93,  0x94, 0x95, 0x96, 0x97,
  61     0x98, 0x99, 0x9A, 0x9B,  0x9C, 0x9D, 0x9E, 0x9F,
  62     0xA0, 0xA1, 0xA2, 0xA3,  0xA4, 0xA5, 0xA6, 0xA7,
  63     0xA8, 0xA9, 0xAA, 0xAB,  0xAC, 0xAD, 0xAE, 0xAF,
  64     0xB0, 0xB1, 0xB2, 0xB3,  0xB4, 0xB5, 0xB6, 0xB7,
  65     0xB8, 0xB9, 0xBA, 0xBB,  0xBC, 0xBD, 0xBE, 0xBF,
  66
  67     0xC0, 0xC1, 0xC2, 0xC3,  0xC4, 0xC5, 0xC6, 0xC7,
  68     0xC8, 0xC9, 0xCA, 0xCB,  0xCC, 0xCD, 0xCE, 0xCF,
  69     0xD0, 0xD1, 0xD2, 0xD3,  0xD4, 0xD5, 0xD6, 0xD7,
  70     0xD8, 0xD9, 0xDA, 0xDB,  0xDC, 0xDD, 0xDE, 0xDF,
  71     0xE0, 0xE1, 0xE2, 0xE3,  0xE4, 0xE5, 0xE6, 0xE7,
  72     0xE8, 0xE9, 0xEA, 0xEB,  0xEC, 0xED, 0xEE, 0xEF,
  73     0xF0, 0xF1, 0xF2, 0xF3,  0xF4, 0xF5, 0xF6, 0xF7,
  74     0xF8, 0xF9, 0xFA, 0xFB,  0xFC, 0xFD, 0xFE, 0xFF,
  75 };
  76
  77
  78 /*=export_func strneqvcmp
  79  *
  80  * what: compare two strings with an equivalence mapping
  81  *
  82  * arg:  + char const* + str1 + first string +
  83  * arg:  + char const* + str2 + second string +
  84  * arg:  + int         + ct   + compare length +
  85  *
  86  * ret_type:  int
  87  * ret_desc:  the difference between two differing characters
  88  *
  89  * doc:
  90  *
  91  * Using a character mapping, two strings are compared for "equivalence".
  92  * Each input character is mapped to a comparison character and the
  93  * mapped-to characters are compared for the two NUL terminated input strings.
  94  * The comparison is limited to @code{ct} bytes.
  95  * This function name is mapped to option_strneqvcmp so as to not conflict
  96  * with the POSIX name space.
  97  *
  98  * err:  none checked.  Caller responsible for seg faults.
  99 =*/
 100 int
 101 strneqvcmp(tCC* s1, tCC* s2, int ct)
 102 {
 103     for (; ct > 0; --ct) {
 104         unsigned char u1 = (unsigned char) *s1++;
 105         unsigned char u2 = (unsigned char) *s2++;
 106         int dif = charmap[ u1 ] - charmap[ u2 ];
 107
 108         if (dif != 0)
 109             return dif;
 110
 111         if (u1 == NUL)
 112             return 0;
 113     }
 114
 115     return 0;
 116 }
 117
 118
 119 /*=export_func streqvcmp
 120  *
 121  * what: compare two strings with an equivalence mapping
 122  *
 123  * arg:  + char const* + str1 + first string +
 124  * arg:  + char const* + str2 + second string +
 125  *
 126  * ret_type:  int
 127  * ret_desc:  the difference between two differing characters
 128  *
 129  * doc:
 130  *
 131  * Using a character mapping, two strings are compared for "equivalence".
 132  * Each input character is mapped to a comparison character and the
 133  * mapped-to characters are compared for the two NUL terminated input strings.
 134  * This function name is mapped to option_streqvcmp so as to not conflict
 135  * with the POSIX name space.
 136  *
 137  * err:  none checked.  Caller responsible for seg faults.
 138 =*/
 139 int
 140 streqvcmp(tCC* s1, tCC* s2)
 141 {
 142     for (;;) {
 143         unsigned char u1 = (unsigned char) *s1++;
 144         unsigned char u2 = (unsigned char) *s2++;
 145         int dif = charmap[ u1 ] - charmap[ u2 ];
 146
 147         if (dif != 0)
 148             return dif;
 149
 150         if (u1 == NUL)
 151             return 0;
 152     }
 153 }
 154
 155
 156 /*=export_func streqvmap
 157  *
 158  * what: Set the character mappings for the streqv functions
 159  *
 160  * arg:  + char + From + Input character +
 161  * arg:  + char + To   + Mapped-to character +
 162  * arg:  + int  + ct   + compare length +
 163  *
 164  * doc:
 165  *
 166  * Set the character mapping.  If the count (@code{ct}) is set to zero, then
 167  * the map is cleared by setting all entries in the map to their index
 168  * value.  Otherwise, the "@code{From}" character is mapped to the "@code{To}"
 169  * character.  If @code{ct} is greater than 1, then @code{From} and @code{To}
 170  * are incremented and the process repeated until @code{ct} entries have been
 171  * set. For example,
 172  * @example
 173  *    streqvmap('a', 'A', 26);
 174  * @end example
 175  * @noindent
 176  * will alter the mapping so that all English lower case letters
 177  * will map to upper case.
 178  *
 179  * This function name is mapped to option_streqvmap so as to not conflict
 180  * with the POSIX name space.
 181  *
 182  * err:  none.
 183 =*/
 184 void
 185 streqvmap(char From, char To, int ct)
 186 {
 187     if (ct == 0) {
 188         ct = sizeof(charmap) - 1;
 189         do  {
 190             charmap[ct] = (unsigned char)ct;
 191         } while (--ct >= 0);
 192     }
 193
 194     else {
 195         unsigned int chTo   = (int)To   & 0xFF;
 196         unsigned int chFrom = (int)From & 0xFF;
 197
 198         do  {
 199             charmap[chFrom] = (unsigned char)chTo;
 200             chFrom++;
 201             chTo++;
 202             if ((chFrom >= sizeof(charmap)) || (chTo >= sizeof(charmap)))
 203                 break;
 204         } while (--ct > 0);
 205     }
 206 }
 207
 208
 209 /*=export_func strequate
 210  *
 211  * what: map a list of characters to the same value
 212  *
 213  * arg:  + char const* + ch_list + characters to equivalence +
 214  *
 215  * doc:
 216  *
 217  * Each character in the input string get mapped to the first character
 218  * in the string.
 219  * This function name is mapped to option_strequate so as to not conflict
 220  * with the POSIX name space.
 221  *
 222  * err:  none.
 223 =*/
 224 void
 225 strequate(char const* s)
 226 {
 227     if ((s != NULL) && (*s != NUL)) {
 228         unsigned char equiv = (unsigned)*s;
 229         while (*s != NUL)
 230             charmap[ (unsigned)*(s++) ] = equiv;
 231     }
 232 }
 233
 234
 235 /*=export_func strtransform
 236  *
 237  * what: convert a string into its mapped-to value
 238  *
 239  * arg:  + char*       + dest + output string +
 240  * arg:  + char const* + src  + input string +
 241  *
 242  * doc:
 243  *
 244  * Each character in the input string is mapped and the mapped-to
 245  * character is put into the output.
 246  * This function name is mapped to option_strtransform so as to not conflict
 247  * with the POSIX name space.
 248  *
 249  * The source and destination may be the same.
 250  *
 251  * err:  none.
 252 =*/
 253 void
 254 strtransform(char* d, char const* s)
 255 {
 256     do  {
 257         *(d++) = (char)charmap[ (unsigned)*s ];
 258     } while (*(s++) != NUL);
 259 }
 260
 261 /*
 262  * Local Variables:
 263  * mode: C
 264  * c-file-style: "stroustrup"
 265  * indent-tabs-mode: nil
 266  * End:
 267  * end of autoopts/streqvcmp.c */