1/*	$NetBSD: streqvcmp.c,v 1.2 2010/12/04 23:08:34 christos Exp $	*/
2
3
4/*
5 *  Id: cb437d22b0c48960c9e1c23501fba6e3291fecd8
6 * Time-stamp:      "2008-12-26 10:15:46 bkorb"
7 *
8 *  String Equivalence Comparison
9 *
10 *  These routines allow any character to be mapped to any other
11 *  character before comparison.  In processing long option names,
12 *  the characters "-", "_" and "^" all need to be equivalent
13 *  (because they are treated so by different development environments).
14 *
15 *  This file is part of AutoOpts, a companion to AutoGen.
16 *  AutoOpts is free software.
17 *  AutoOpts is copyright (c) 1992-2009 by Bruce Korb - all rights reserved
18 *
19 *  AutoOpts is available under any one of two licenses.  The license
20 *  in use must be one of these two and the choice is under the control
21 *  of the user of the license.
22 *
23 *   The GNU Lesser General Public License, version 3 or later
24 *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
25 *
26 *   The Modified Berkeley Software Distribution License
27 *      See the file "COPYING.mbsd"
28 *
29 *  These files have the following md5sums:
30 *
31 *  43b91e8ca915626ed3818ffb1b71248b pkg/libopts/COPYING.gplv3
32 *  06a1a2e4760c90ea5e1dad8dfaac4d39 pkg/libopts/COPYING.lgplv3
33 *  66a5cedaf62c4b2637025f049f9b826f pkg/libopts/COPYING.mbsd
34 *
35 * This array is designed for mapping upper and lower case letter
36 * together for a case independent comparison.  The mappings are
37 * based upon ascii character sequences.
38 */
39static unsigned char charmap[] = {
40    0x00, 0x01, 0x02, 0x03,  0x04, 0x05, 0x06, '\a',
41    '\b', '\t', '\n', '\v',  '\f', '\r', 0x0E, 0x0F,
42    0x10, 0x11, 0x12, 0x13,  0x14, 0x15, 0x16, 0x17,
43    0x18, 0x19, 0x1A, 0x1B,  0x1C, 0x1D, 0x1E, 0x1F,
44
45    ' ',  '!',  '"',  '#',   '$',  '%',  '&',  '\'',
46    '(',  ')',  '*',  '+',   ',',  '-',  '.',  '/',
47    '0',  '1',  '2',  '3',   '4',  '5',  '6',  '7',
48    '8',  '9',  ':',  ';',   '<',  '=',  '>',  '?',
49
50    '@',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
51    'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
52    'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
53    'x',  'y',  'z',  '[',   '\\', ']',  '^',  '_',
54    '`',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
55    'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
56    'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
57    'x',  'y',  'z',  '{',   '|',  '}',  '~',  0x7f,
58
59    0x80, 0x81, 0x82, 0x83,  0x84, 0x85, 0x86, 0x87,
60    0x88, 0x89, 0x8A, 0x8B,  0x8C, 0x8D, 0x8E, 0x8F,
61    0x90, 0x91, 0x92, 0x93,  0x94, 0x95, 0x96, 0x97,
62    0x98, 0x99, 0x9A, 0x9B,  0x9C, 0x9D, 0x9E, 0x9F,
63    0xA0, 0xA1, 0xA2, 0xA3,  0xA4, 0xA5, 0xA6, 0xA7,
64    0xA8, 0xA9, 0xAA, 0xAB,  0xAC, 0xAD, 0xAE, 0xAF,
65    0xB0, 0xB1, 0xB2, 0xB3,  0xB4, 0xB5, 0xB6, 0xB7,
66    0xB8, 0xB9, 0xBA, 0xBB,  0xBC, 0xBD, 0xBE, 0xBF,
67
68    0xC0, 0xC1, 0xC2, 0xC3,  0xC4, 0xC5, 0xC6, 0xC7,
69    0xC8, 0xC9, 0xCA, 0xCB,  0xCC, 0xCD, 0xCE, 0xCF,
70    0xD0, 0xD1, 0xD2, 0xD3,  0xD4, 0xD5, 0xD6, 0xD7,
71    0xD8, 0xD9, 0xDA, 0xDB,  0xDC, 0xDD, 0xDE, 0xDF,
72    0xE0, 0xE1, 0xE2, 0xE3,  0xE4, 0xE5, 0xE6, 0xE7,
73    0xE8, 0xE9, 0xEA, 0xEB,  0xEC, 0xED, 0xEE, 0xEF,
74    0xF0, 0xF1, 0xF2, 0xF3,  0xF4, 0xF5, 0xF6, 0xF7,
75    0xF8, 0xF9, 0xFA, 0xFB,  0xFC, 0xFD, 0xFE, 0xFF,
76};
77
78
79/*=export_func strneqvcmp
80 *
81 * what: compare two strings with an equivalence mapping
82 *
83 * arg:  + char const* + str1 + first string +
84 * arg:  + char const* + str2 + second string +
85 * arg:  + int         + ct   + compare length +
86 *
87 * ret_type:  int
88 * ret_desc:  the difference between two differing characters
89 *
90 * doc:
91 *
92 * Using a character mapping, two strings are compared for "equivalence".
93 * Each input character is mapped to a comparison character and the
94 * mapped-to characters are compared for the two NUL terminated input strings.
95 * The comparison is limited to @code{ct} bytes.
96 * This function name is mapped to option_strneqvcmp so as to not conflict
97 * with the POSIX name space.
98 *
99 * err:  none checked.  Caller responsible for seg faults.
100=*/
101int
102strneqvcmp( tCC* s1, tCC* s2, int ct )
103{
104    for (; ct > 0; --ct) {
105        unsigned char u1 = (unsigned char) *s1++;
106        unsigned char u2 = (unsigned char) *s2++;
107        int dif = charmap[ u1 ] - charmap[ u2 ];
108
109        if (dif != 0)
110            return dif;
111
112        if (u1 == NUL)
113            return 0;
114    }
115
116    return 0;
117}
118
119
120/*=export_func streqvcmp
121 *
122 * what: compare two strings with an equivalence mapping
123 *
124 * arg:  + char const* + str1 + first string +
125 * arg:  + char const* + str2 + second string +
126 *
127 * ret_type:  int
128 * ret_desc:  the difference between two differing characters
129 *
130 * doc:
131 *
132 * Using a character mapping, two strings are compared for "equivalence".
133 * Each input character is mapped to a comparison character and the
134 * mapped-to characters are compared for the two NUL terminated input strings.
135 * This function name is mapped to option_streqvcmp so as to not conflict
136 * with the POSIX name space.
137 *
138 * err:  none checked.  Caller responsible for seg faults.
139=*/
140int
141streqvcmp( tCC* s1, tCC* s2 )
142{
143    for (;;) {
144        unsigned char u1 = (unsigned char) *s1++;
145        unsigned char u2 = (unsigned char) *s2++;
146        int dif = charmap[ u1 ] - charmap[ u2 ];
147
148        if (dif != 0)
149            return dif;
150
151        if (u1 == NUL)
152            return 0;
153    }
154}
155
156
157/*=export_func streqvmap
158 *
159 * what: Set the character mappings for the streqv functions
160 *
161 * arg:  + char + From + Input character +
162 * arg:  + char + To   + Mapped-to character +
163 * arg:  + int  + ct   + compare length +
164 *
165 * doc:
166 *
167 * Set the character mapping.  If the count (@code{ct}) is set to zero, then
168 * the map is cleared by setting all entries in the map to their index
169 * value.  Otherwise, the "@code{From}" character is mapped to the "@code{To}"
170 * character.  If @code{ct} is greater than 1, then @code{From} and @code{To}
171 * are incremented and the process repeated until @code{ct} entries have been
172 * set. For example,
173 * @example
174 *    streqvmap( 'a', 'A', 26 );
175 * @end example
176 * @noindent
177 * will alter the mapping so that all English lower case letters
178 * will map to upper case.
179 *
180 * This function name is mapped to option_streqvmap so as to not conflict
181 * with the POSIX name space.
182 *
183 * err:  none.
184=*/
185void
186streqvmap( char From, char To, int ct )
187{
188    if (ct == 0) {
189        ct = sizeof( charmap ) - 1;
190        do  {
191            charmap[ ct ] = ct;
192        } while (--ct >= 0);
193    }
194
195    else {
196        size_t  chTo   = (size_t)To   & 0xFF;
197        size_t  chFrom = (size_t)From & 0xFF;
198
199        do  {
200            charmap[ chFrom ] = (unsigned)chTo;
201            chFrom++;
202            chTo++;
203            if ((chFrom >= sizeof( charmap )) || (chTo >= sizeof( charmap )))
204                break;
205        } while (--ct > 0);
206    }
207}
208
209
210/*=export_func strequate
211 *
212 * what: map a list of characters to the same value
213 *
214 * arg:  + char const* + ch_list + characters to equivalence +
215 *
216 * doc:
217 *
218 * Each character in the input string get mapped to the first character
219 * in the string.
220 * This function name is mapped to option_strequate so as to not conflict
221 * with the POSIX name space.
222 *
223 * err:  none.
224=*/
225void
226strequate( char const* s )
227{
228    if ((s != NULL) && (*s != NUL)) {
229        unsigned char equiv = (unsigned)*s;
230        while (*s != NUL)
231            charmap[ (unsigned)*(s++) ] = equiv;
232    }
233}
234
235
236/*=export_func strtransform
237 *
238 * what: convert a string into its mapped-to value
239 *
240 * arg:  + char*       + dest + output string +
241 * arg:  + char const* + src  + input string +
242 *
243 * doc:
244 *
245 * Each character in the input string is mapped and the mapped-to
246 * character is put into the output.
247 * This function name is mapped to option_strtransform so as to not conflict
248 * with the POSIX name space.
249 *
250 * The source and destination may be the same.
251 *
252 * err:  none.
253=*/
254void
255strtransform( char* d, char const* s )
256{
257    do  {
258        *(d++) = (char)charmap[ (unsigned)*s ];
259    } while (*(s++) != NUL);
260}
261
262/*
263 * Local Variables:
264 * mode: C
265 * c-file-style: "stroustrup"
266 * indent-tabs-mode: nil
267 * End:
268 * end of autoopts/streqvcmp.c */
269