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-NetBSD
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  * $FreeBSD: head/usr.sbin/makefs/cd9660/cd9660_conversion.c 326276 2017-11-27 15:37:16Z pfg $
37  */
38 #include "cd9660.h"
39 
40 static char cd9660_compute_gm_offset(time_t);
41 
42 #if 0
43 static inline int
44 cd9660_pad_even(length)
45 int length;
46 {
47 	return length + (length & 0x01);
48 }
49 #endif
50 
51 /*
52 * These can probably be implemented using a macro
53 */
54 
55 /* Little endian */
56 void
57 cd9660_721(uint16_t w, unsigned char *twochar)
58 {
59 #if BYTE_ORDER == BIG_ENDIAN
60 	w = bswap16(w);
61 #endif
62 	memcpy(twochar,&w,2);
63 }
64 
65 void
66 cd9660_731(uint32_t w, unsigned char *fourchar)
67 {
68 #if BYTE_ORDER == BIG_ENDIAN
69 	w = bswap32(w);
70 #endif
71 	memcpy(fourchar,&w,4);
72 }
73 
74 /* Big endian */
75 void
76 cd9660_722(uint16_t w, unsigned char *twochar)
77 {
78 #if BYTE_ORDER == LITTLE_ENDIAN
79 	w = bswap16(w);
80 #endif
81 	memcpy(twochar,&w,2);
82 }
83 
84 void
85 cd9660_732(uint32_t w, unsigned char *fourchar)
86 {
87 #if BYTE_ORDER == LITTLE_ENDIAN
88 	w = bswap32(w);
89 #endif
90 	memcpy(fourchar,&w,4);
91 }
92 
93 /**
94 * Convert a dword into a double endian string of eight characters
95 * @param int The double word to convert
96 * @param char* The string to write the both endian double word to - It is assumed this is allocated and at least
97 *		eight characters long
98 */
99 void
100 cd9660_bothendian_dword(uint32_t dw, unsigned char *eightchar)
101 {
102 	uint32_t le, be;
103 #if BYTE_ORDER == LITTLE_ENDIAN
104 	le = dw;
105 	be = bswap32(dw);
106 #endif
107 #if BYTE_ORDER == BIG_ENDIAN
108 	be = dw;
109 	le = bswap32(dw);
110 #endif
111 	memcpy(eightchar, &le, 4);
112 	memcpy((eightchar+4), &be, 4);
113 }
114 
115 /**
116 * Convert a word into a double endian string of four characters
117 * @param int The word to convert
118 * @param char* The string to write the both endian word to - It is assumed this is allocated and at least
119 *		four characters long
120 */
121 void
122 cd9660_bothendian_word(uint16_t dw, unsigned char *fourchar)
123 {
124 	uint16_t le, be;
125 #if BYTE_ORDER == LITTLE_ENDIAN
126 	le = dw;
127 	be = bswap16(dw);
128 #endif
129 #if BYTE_ORDER == BIG_ENDIAN
130 	be = dw;
131 	le = bswap16(dw);
132 #endif
133 	memcpy(fourchar, &le, 2);
134 	memcpy((fourchar+2), &be, 2);
135 }
136 
137 void
138 cd9660_pad_string_spaces(char *str, int len)
139 {
140 	int i;
141 
142 	for (i = 0; i < len; i ++) {
143 		if (str[i] == '\0')
144 			str[i] = 0x20;
145 	}
146 }
147 
148 static char
149 cd9660_compute_gm_offset(time_t tim)
150 {
151 	struct tm t, gm;
152 
153 	(void)localtime_r(&tim, &t);
154 	(void)gmtime_r(&tim, &gm);
155 	gm.tm_year -= t.tm_year;
156 	gm.tm_yday -= t.tm_yday;
157 	gm.tm_hour -= t.tm_hour;
158 	gm.tm_min  -= t.tm_min;
159 	if (gm.tm_year < 0)
160 		gm.tm_yday = -1;
161 	else if (gm.tm_year > 0)
162 		gm.tm_yday = 1;
163 
164 	return (char)(-(gm.tm_min + 60* (24 * gm.tm_yday + gm.tm_hour)) / 15);
165 }
166 
167 /* Long dates: 17 characters */
168 void
169 cd9660_time_8426(unsigned char *buf, time_t tim)
170 {
171 	struct tm t;
172 	char temp[18];
173 
174 	(void)localtime_r(&tim, &t);
175 	(void)snprintf(temp, sizeof(temp), "%04i%02i%02i%02i%02i%02i%02i",
176 		1900+(int)t.tm_year,
177 		(int)t.tm_mon+1,
178 		(int)t.tm_mday,
179 		(int)t.tm_hour,
180 		(int)t.tm_min,
181 		(int)t.tm_sec,
182 		0);
183 	(void)memcpy(buf, temp, 16);
184 	buf[16] = cd9660_compute_gm_offset(tim);
185 }
186 
187 /* Short dates: 7 characters */
188 void
189 cd9660_time_915(unsigned char *buf, time_t tim)
190 {
191 	struct tm t;
192 
193 	(void)localtime_r(&tim, &t);
194 	buf[0] = t.tm_year;
195 	buf[1] = t.tm_mon+1;
196 	buf[2] = t.tm_mday;
197 	buf[3] = t.tm_hour;
198 	buf[4] = t.tm_min;
199 	buf[5] = t.tm_sec;
200 	buf[6] = cd9660_compute_gm_offset(tim);
201 }
202