1/*	$NetBSD: streqvcmp.c,v 1.1.1.2 2012/01/31 21:27:54 kardel Exp $	*/
2
3
4/**
5 * \file streqvcmp.c
6 *
7 * Time-stamp:      "2010-07-17 10:16:24 bkorb"
8 *
9 *  String Equivalence Comparison
10 *
11 *  These routines allow any character to be mapped to any other
12 *  character before comparison.  In processing long option names,
13 *  the characters "-", "_" and "^" all need to be equivalent
14 *  (because they are treated so by different development environments).
15 *
16 *  This file is part of AutoOpts, a companion to AutoGen.
17 *  AutoOpts is free software.
18 *  AutoOpts is Copyright (c) 1992-2011 by Bruce Korb - all rights reserved
19 *
20 *  AutoOpts is available under any one of two licenses.  The license
21 *  in use must be one of these two and the choice is under the control
22 *  of the user of the license.
23 *
24 *   The GNU Lesser General Public License, version 3 or later
25 *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
26 *
27 *   The Modified Berkeley Software Distribution License
28 *      See the file "COPYING.mbsd"
29 *
30 *  These files have the following md5sums:
31 *
32 *  43b91e8ca915626ed3818ffb1b71248b pkg/libopts/COPYING.gplv3
33 *  06a1a2e4760c90ea5e1dad8dfaac4d39 pkg/libopts/COPYING.lgplv3
34 *  66a5cedaf62c4b2637025f049f9b826f pkg/libopts/COPYING.mbsd
35 *
36 * This array is designed for mapping upper and lower case letter
37 * together for a case independent comparison.  The mappings are
38 * based upon ascii character sequences.
39 */
40static unsigned char charmap[] = {
41    0x00, 0x01, 0x02, 0x03,  0x04, 0x05, 0x06, '\a',
42    '\b', '\t', '\n', '\v',  '\f', '\r', 0x0E, 0x0F,
43    0x10, 0x11, 0x12, 0x13,  0x14, 0x15, 0x16, 0x17,
44    0x18, 0x19, 0x1A, 0x1B,  0x1C, 0x1D, 0x1E, 0x1F,
45
46    ' ',  '!',  '"',  '#',   '$',  '%',  '&',  '\'',
47    '(',  ')',  '*',  '+',   ',',  '-',  '.',  '/',
48    '0',  '1',  '2',  '3',   '4',  '5',  '6',  '7',
49    '8',  '9',  ':',  ';',   '<',  '=',  '>',  '?',
50
51    '@',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
52    'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
53    'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
54    'x',  'y',  'z',  '[',   '\\', ']',  '^',  '_',
55    '`',  'a',  'b',  'c',   'd',  'e',  'f',  'g',
56    'h',  'i',  'j',  'k',   'l',  'm',  'n',  'o',
57    'p',  'q',  'r',  's',   't',  'u',  'v',  'w',
58    'x',  'y',  'z',  '{',   '|',  '}',  '~',  0x7f,
59
60    0x80, 0x81, 0x82, 0x83,  0x84, 0x85, 0x86, 0x87,
61    0x88, 0x89, 0x8A, 0x8B,  0x8C, 0x8D, 0x8E, 0x8F,
62    0x90, 0x91, 0x92, 0x93,  0x94, 0x95, 0x96, 0x97,
63    0x98, 0x99, 0x9A, 0x9B,  0x9C, 0x9D, 0x9E, 0x9F,
64    0xA0, 0xA1, 0xA2, 0xA3,  0xA4, 0xA5, 0xA6, 0xA7,
65    0xA8, 0xA9, 0xAA, 0xAB,  0xAC, 0xAD, 0xAE, 0xAF,
66    0xB0, 0xB1, 0xB2, 0xB3,  0xB4, 0xB5, 0xB6, 0xB7,
67    0xB8, 0xB9, 0xBA, 0xBB,  0xBC, 0xBD, 0xBE, 0xBF,
68
69    0xC0, 0xC1, 0xC2, 0xC3,  0xC4, 0xC5, 0xC6, 0xC7,
70    0xC8, 0xC9, 0xCA, 0xCB,  0xCC, 0xCD, 0xCE, 0xCF,
71    0xD0, 0xD1, 0xD2, 0xD3,  0xD4, 0xD5, 0xD6, 0xD7,
72    0xD8, 0xD9, 0xDA, 0xDB,  0xDC, 0xDD, 0xDE, 0xDF,
73    0xE0, 0xE1, 0xE2, 0xE3,  0xE4, 0xE5, 0xE6, 0xE7,
74    0xE8, 0xE9, 0xEA, 0xEB,  0xEC, 0xED, 0xEE, 0xEF,
75    0xF0, 0xF1, 0xF2, 0xF3,  0xF4, 0xF5, 0xF6, 0xF7,
76    0xF8, 0xF9, 0xFA, 0xFB,  0xFC, 0xFD, 0xFE, 0xFF,
77};
78
79
80/*=export_func strneqvcmp
81 *
82 * what: compare two strings with an equivalence mapping
83 *
84 * arg:  + char const* + str1 + first string +
85 * arg:  + char const* + str2 + second string +
86 * arg:  + int         + ct   + compare length +
87 *
88 * ret_type:  int
89 * ret_desc:  the difference between two differing characters
90 *
91 * doc:
92 *
93 * Using a character mapping, two strings are compared for "equivalence".
94 * Each input character is mapped to a comparison character and the
95 * mapped-to characters are compared for the two NUL terminated input strings.
96 * The comparison is limited to @code{ct} bytes.
97 * This function name is mapped to option_strneqvcmp so as to not conflict
98 * with the POSIX name space.
99 *
100 * err:  none checked.  Caller responsible for seg faults.
101=*/
102int
103strneqvcmp(tCC* s1, tCC* s2, int ct)
104{
105    for (; ct > 0; --ct) {
106        unsigned char u1 = (unsigned char) *s1++;
107        unsigned char u2 = (unsigned char) *s2++;
108        int dif = charmap[ u1 ] - charmap[ u2 ];
109
110        if (dif != 0)
111            return dif;
112
113        if (u1 == NUL)
114            return 0;
115    }
116
117    return 0;
118}
119
120
121/*=export_func streqvcmp
122 *
123 * what: compare two strings with an equivalence mapping
124 *
125 * arg:  + char const* + str1 + first string +
126 * arg:  + char const* + str2 + second string +
127 *
128 * ret_type:  int
129 * ret_desc:  the difference between two differing characters
130 *
131 * doc:
132 *
133 * Using a character mapping, two strings are compared for "equivalence".
134 * Each input character is mapped to a comparison character and the
135 * mapped-to characters are compared for the two NUL terminated input strings.
136 * This function name is mapped to option_streqvcmp so as to not conflict
137 * with the POSIX name space.
138 *
139 * err:  none checked.  Caller responsible for seg faults.
140=*/
141int
142streqvcmp(tCC* s1, tCC* s2)
143{
144    for (;;) {
145        unsigned char u1 = (unsigned char) *s1++;
146        unsigned char u2 = (unsigned char) *s2++;
147        int dif = charmap[ u1 ] - charmap[ u2 ];
148
149        if (dif != 0)
150            return dif;
151
152        if (u1 == NUL)
153            return 0;
154    }
155}
156
157
158/*=export_func streqvmap
159 *
160 * what: Set the character mappings for the streqv functions
161 *
162 * arg:  + char + From + Input character +
163 * arg:  + char + To   + Mapped-to character +
164 * arg:  + int  + ct   + compare length +
165 *
166 * doc:
167 *
168 * Set the character mapping.  If the count (@code{ct}) is set to zero, then
169 * the map is cleared by setting all entries in the map to their index
170 * value.  Otherwise, the "@code{From}" character is mapped to the "@code{To}"
171 * character.  If @code{ct} is greater than 1, then @code{From} and @code{To}
172 * are incremented and the process repeated until @code{ct} entries have been
173 * set. For example,
174 * @example
175 *    streqvmap('a', 'A', 26);
176 * @end example
177 * @noindent
178 * will alter the mapping so that all English lower case letters
179 * will map to upper case.
180 *
181 * This function name is mapped to option_streqvmap so as to not conflict
182 * with the POSIX name space.
183 *
184 * err:  none.
185=*/
186void
187streqvmap(char From, char To, int ct)
188{
189    if (ct == 0) {
190        ct = sizeof(charmap) - 1;
191        do  {
192            charmap[ ct ] = ct;
193        } while (--ct >= 0);
194    }
195
196    else {
197        size_t  chTo   = (int)To   & 0xFF;
198        size_t  chFrom = (int)From & 0xFF;
199
200        do  {
201            charmap[ chFrom ] = (unsigned)chTo;
202            chFrom++;
203            chTo++;
204            if ((chFrom >= sizeof(charmap)) || (chTo >= sizeof(charmap)))
205                break;
206        } while (--ct > 0);
207    }
208}
209
210
211/*=export_func strequate
212 *
213 * what: map a list of characters to the same value
214 *
215 * arg:  + char const* + ch_list + characters to equivalence +
216 *
217 * doc:
218 *
219 * Each character in the input string get mapped to the first character
220 * in the string.
221 * This function name is mapped to option_strequate so as to not conflict
222 * with the POSIX name space.
223 *
224 * err:  none.
225=*/
226void
227strequate(char const* s)
228{
229    if ((s != NULL) && (*s != NUL)) {
230        unsigned char equiv = (unsigned)*s;
231        while (*s != NUL)
232            charmap[ (unsigned)*(s++) ] = equiv;
233    }
234}
235
236
237/*=export_func strtransform
238 *
239 * what: convert a string into its mapped-to value
240 *
241 * arg:  + char*       + dest + output string +
242 * arg:  + char const* + src  + input string +
243 *
244 * doc:
245 *
246 * Each character in the input string is mapped and the mapped-to
247 * character is put into the output.
248 * This function name is mapped to option_strtransform so as to not conflict
249 * with the POSIX name space.
250 *
251 * The source and destination may be the same.
252 *
253 * err:  none.
254=*/
255void
256strtransform(char* d, char const* s)
257{
258    do  {
259        *(d++) = (char)charmap[ (unsigned)*s ];
260    } while (*(s++) != NUL);
261}
262
263/*
264 * Local Variables:
265 * mode: C
266 * c-file-style: "stroustrup"
267 * indent-tabs-mode: nil
268 * End:
269 * end of autoopts/streqvcmp.c */
270