1/*
2
3Copyright 1990, 1994, 1998  The Open Group
4
5Permission to use, copy, modify, distribute, and sell this software and its
6documentation for any purpose is hereby granted without fee, provided that
7the above copyright notice appear in all copies and that both that
8copyright notice and this permission notice appear in supporting
9documentation.
10
11The above copyright notice and this permission notice shall be included in
12all copies or substantial portions of the Software.
13
14THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
17OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
18AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
19CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20
21Except as contained in this notice, the name of The Open Group shall not be
22used in advertising or otherwise to promote the sale, use or other dealings
23in this Software without prior written authorization from The Open Group.
24
25*/
26
27/*
28 * Author:  Keith Packard, MIT X Consortium
29 */
30
31#ifdef HAVE_CONFIG_H
32#include <config.h>
33#endif
34#include "fontmisc.h"
35
36/* Utility functions for reformatting font bitmaps */
37
38static const unsigned char _reverse_byte[0x100] = {
39    0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
40    0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
41    0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
42    0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
43    0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
44    0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
45    0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
46    0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
47    0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
48    0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
49    0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
50    0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
51    0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
52    0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
53    0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
54    0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
55    0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
56    0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
57    0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
58    0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
59    0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
60    0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
61    0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
62    0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
63    0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
64    0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
65    0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
66    0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
67    0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
68    0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
69    0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
70    0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff
71};
72
73/*
74 *	Invert bit order within each BYTE of an array.
75 */
76void
77BitOrderInvert(unsigned char *buf, int nbytes)
78{
79    const unsigned char *rev = _reverse_byte;
80
81    for (; --nbytes >= 0; buf++)
82        *buf = rev[*buf];
83}
84
85/*
86 *	Invert byte order within each 16-bits of an array.
87 */
88void
89TwoByteSwap(unsigned char *buf, int nbytes)
90{
91    for (; nbytes > 0; nbytes -= 2, buf += 2) {
92        unsigned char c;
93
94        c = buf[0];
95        buf[0] = buf[1];
96        buf[1] = c;
97    }
98}
99
100/*
101 *	Invert byte order within each 32-bits of an array.
102 */
103void
104FourByteSwap(unsigned char *buf, int nbytes)
105{
106    for (; nbytes > 0; nbytes -= 4, buf += 4) {
107        unsigned char c;
108
109        c = buf[0];
110        buf[0] = buf[3];
111        buf[3] = c;
112
113        c = buf[1];
114        buf[1] = buf[2];
115        buf[2] = c;
116    }
117}
118