Wibble in docs for new ForeignPtr functionsn
[packages/random.git] / cbits / fpstring.c
1 /*
2 * Copyright (c) 2003 David Roundy
3 * Copyright (c) 2005-6 Don Stewart
4 *
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the names of the authors or the names of any contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include "fpstring.h"
33
34 /* copy a string in reverse */
35 void reverse(unsigned char *dest, unsigned char *from, int len) {
36 unsigned char *p, *q;
37 p = from + len - 1;
38 q = dest;
39
40 while (p >= from)
41 *q++ = *p--;
42 }
43
44 /* duplicate a string, interspersing the character through the elements
45 of the duplicated string */
46 void intersperse(unsigned char *dest, unsigned char *from, int len, char c) {
47 unsigned char *p, *q;
48 p = from;
49 q = dest;
50 while (p < from + len - 1) {
51 *q++ = *p++;
52 *q++ = c;
53 }
54 *q = *p;
55 }
56
57 /* find maximum char in a packed string */
58 unsigned char maximum(unsigned char *p, int len) {
59 unsigned char *q, c = *p;
60 for (q = p; q < p + len; q++)
61 if (*q > c)
62 c = *q;
63 return c;
64 }
65
66 /* find minimum char in a packed string */
67 unsigned char minimum(unsigned char *p, int len) {
68 unsigned char *q, c = *p;
69 for (q = p; q < p + len; q++)
70 if (*q < c)
71 c = *q;
72 return c;
73 }
74
75 /* count the number of occurences of a char in a string */
76 int count(unsigned char *p, int len, unsigned char w) {
77 int c;
78 for (c = 0; len--; ++p)
79 if (*p == w)
80 ++c;
81 return c;
82 }