xref: /freebsd/usr.sbin/makefs/cd9660/cd9660_conversion.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1 /*	$NetBSD: cd9660_conversion.c,v 1.4 2007/03/14 14:11:17 christos Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause
5  *
6  * Copyright (c) 2005 Daniel Watt, Walter Deignan, Ryan Gabrys, Alan
7  * Perez-Rathke and Ram Vedam.  All rights reserved.
8  *
9  * This code was written by Daniel Watt, Walter Deignan, Ryan Gabrys,
10  * Alan Perez-Rathke and Ram Vedam.
11  *
12  * Redistribution and use in source and binary forms, with or
13  * without modification, are permitted provided that the following
14  * conditions are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above
18  *    copyright notice, this list of conditions and the following
19  *    disclaimer in the documentation and/or other materials provided
20  *    with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY DANIEL WATT, WALTER DEIGNAN, RYAN
23  * GABRYS, ALAN PEREZ-RATHKE AND RAM VEDAM ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  * DISCLAIMED.  IN NO EVENT SHALL DANIEL WATT, WALTER DEIGNAN, RYAN
27  * GABRYS, ALAN PEREZ-RATHKE AND RAM VEDAM BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
30  * USE,DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
31  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
34  * OF SUCH DAMAGE.
35  */
36 #include "cd9660.h"
37 
38 #include <sys/cdefs.h>
39 static char cd9660_compute_gm_offset(time_t);
40 
41 #if 0
42 static inline int
43 cd9660_pad_even(length)
44 int length;
45 {
46 	return length + (length & 0x01);
47 }
48 #endif
49 
50 /*
51 * These can probably be implemented using a macro
52 */
53 
54 /* Little endian */
55 void
56 cd9660_721(uint16_t w, unsigned char *twochar)
57 {
58 #if BYTE_ORDER == BIG_ENDIAN
59 	w = bswap16(w);
60 #endif
61 	memcpy(twochar,&w,2);
62 }
63 
64 void
65 cd9660_731(uint32_t w, unsigned char *fourchar)
66 {
67 #if BYTE_ORDER == BIG_ENDIAN
68 	w = bswap32(w);
69 #endif
70 	memcpy(fourchar,&w,4);
71 }
72 
73 /* Big endian */
74 void
75 cd9660_722(uint16_t w, unsigned char *twochar)
76 {
77 #if BYTE_ORDER == LITTLE_ENDIAN
78 	w = bswap16(w);
79 #endif
80 	memcpy(twochar,&w,2);
81 }
82 
83 void
84 cd9660_732(uint32_t w, unsigned char *fourchar)
85 {
86 #if BYTE_ORDER == LITTLE_ENDIAN
87 	w = bswap32(w);
88 #endif
89 	memcpy(fourchar,&w,4);
90 }
91 
92 /**
93 * Convert a dword into a double endian string of eight characters
94 * @param int The double word to convert
95 * @param char* The string to write the both endian double word to - It is assumed this is allocated and at least
96 *		eight characters long
97 */
98 void
99 cd9660_bothendian_dword(uint32_t dw, unsigned char *eightchar)
100 {
101 	uint32_t le, be;
102 #if BYTE_ORDER == LITTLE_ENDIAN
103 	le = dw;
104 	be = bswap32(dw);
105 #endif
106 #if BYTE_ORDER == BIG_ENDIAN
107 	be = dw;
108 	le = bswap32(dw);
109 #endif
110 	memcpy(eightchar, &le, 4);
111 	memcpy((eightchar+4), &be, 4);
112 }
113 
114 /**
115 * Convert a word into a double endian string of four characters
116 * @param int The word to convert
117 * @param char* The string to write the both endian word to - It is assumed this is allocated and at least
118 *		four characters long
119 */
120 void
121 cd9660_bothendian_word(uint16_t dw, unsigned char *fourchar)
122 {
123 	uint16_t le, be;
124 #if BYTE_ORDER == LITTLE_ENDIAN
125 	le = dw;
126 	be = bswap16(dw);
127 #endif
128 #if BYTE_ORDER == BIG_ENDIAN
129 	be = dw;
130 	le = bswap16(dw);
131 #endif
132 	memcpy(fourchar, &le, 2);
133 	memcpy((fourchar+2), &be, 2);
134 }
135 
136 void
137 cd9660_pad_string_spaces(char *str, int len)
138 {
139 	int i;
140 
141 	for (i = 0; i < len; i ++) {
142 		if (str[i] == '\0')
143 			str[i] = 0x20;
144 	}
145 }
146 
147 static char
148 cd9660_compute_gm_offset(time_t tim)
149 {
150 	struct tm t, gm;
151 
152 	(void)localtime_r(&tim, &t);
153 	(void)gmtime_r(&tim, &gm);
154 	gm.tm_year -= t.tm_year;
155 	gm.tm_yday -= t.tm_yday;
156 	gm.tm_hour -= t.tm_hour;
157 	gm.tm_min  -= t.tm_min;
158 	if (gm.tm_year < 0)
159 		gm.tm_yday = -1;
160 	else if (gm.tm_year > 0)
161 		gm.tm_yday = 1;
162 
163 	return (char)(-(gm.tm_min + 60* (24 * gm.tm_yday + gm.tm_hour)) / 15);
164 }
165 
166 /* Long dates: 17 characters */
167 void
168 cd9660_time_8426(unsigned char *buf, time_t tim)
169 {
170 	struct tm t;
171 	char temp[18];
172 
173 	(void)localtime_r(&tim, &t);
174 	(void)snprintf(temp, sizeof(temp), "%04i%02i%02i%02i%02i%02i%02i",
175 		1900+(int)t.tm_year,
176 		(int)t.tm_mon+1,
177 		(int)t.tm_mday,
178 		(int)t.tm_hour,
179 		(int)t.tm_min,
180 		(int)t.tm_sec,
181 		0);
182 	(void)memcpy(buf, temp, 16);
183 	buf[16] = cd9660_compute_gm_offset(tim);
184 }
185 
186 /* Short dates: 7 characters */
187 void
188 cd9660_time_915(unsigned char *buf, time_t tim)
189 {
190 	struct tm t;
191 
192 	(void)localtime_r(&tim, &t);
193 	buf[0] = t.tm_year;
194 	buf[1] = t.tm_mon+1;
195 	buf[2] = t.tm_mday;
196 	buf[3] = t.tm_hour;
197 	buf[4] = t.tm_min;
198 	buf[5] = t.tm_sec;
199 	buf[6] = cd9660_compute_gm_offset(tim);
200 }
201