1 /*	$NetBSD: cd9660_conversion.c,v 1.4 2007/03/14 14:11:17 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Daniel Watt, Walter Deignan, Ryan Gabrys, Alan
5  * Perez-Rathke and Ram Vedam.  All rights reserved.
6  *
7  * This code was written by Daniel Watt, Walter Deignan, Ryan Gabrys,
8  * Alan Perez-Rathke and Ram Vedam.
9  *
10  * Redistribution and use in source and binary forms, with or
11  * without modification, are permitted provided that the following
12  * conditions are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above
16  *    copyright notice, this list of conditions and the following
17  *    disclaimer in the documentation and/or other materials provided
18  *    with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY DANIEL WATT, WALTER DEIGNAN, RYAN
21  * GABRYS, ALAN PEREZ-RATHKE AND RAM VEDAM ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24  * DISCLAIMED.  IN NO EVENT SHALL DANIEL WATT, WALTER DEIGNAN, RYAN
25  * GABRYS, ALAN PEREZ-RATHKE AND RAM VEDAM BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28  * USE,DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
32  * OF SUCH DAMAGE.
33  */
34 #include "cd9660.h"
35 
36 #include <sys/cdefs.h>
37 #if defined(__RCSID) && !defined(__lint)
38 __RCSID("$NetBSD: cd9660_conversion.c,v 1.4 2007/03/14 14:11:17 christos Exp $");
39 #endif  /* !__lint */
40 
41 
42 static char cd9660_compute_gm_offset(time_t);
43 
44 #if 0
45 static inline int
46 cd9660_pad_even(length)
47 int length;
48 {
49 	return length + (length & 0x01);
50 }
51 #endif
52 
53 /*
54 * These can probably be implemented using a macro
55 */
56 
57 /* Little endian */
58 void
cd9660_721(uint16_t w,unsigned char * twochar)59 cd9660_721(uint16_t w, unsigned char *twochar)
60 {
61 #if BYTE_ORDER == BIG_ENDIAN
62 	w = bswap16(w);
63 #endif
64 	memcpy(twochar,&w,2);
65 }
66 
67 void
cd9660_731(uint32_t w,unsigned char * fourchar)68 cd9660_731(uint32_t w, unsigned char *fourchar)
69 {
70 #if BYTE_ORDER == BIG_ENDIAN
71 	w = bswap32(w);
72 #endif
73 	memcpy(fourchar,&w,4);
74 }
75 
76 /* Big endian */
77 void
cd9660_722(uint16_t w,unsigned char * twochar)78 cd9660_722(uint16_t w, unsigned char *twochar)
79 {
80 #if BYTE_ORDER == LITTLE_ENDIAN
81 	w = bswap16(w);
82 #endif
83 	memcpy(twochar,&w,2);
84 }
85 
86 void
cd9660_732(uint32_t w,unsigned char * fourchar)87 cd9660_732(uint32_t w, unsigned char *fourchar)
88 {
89 #if BYTE_ORDER == LITTLE_ENDIAN
90 	w = bswap32(w);
91 #endif
92 	memcpy(fourchar,&w,4);
93 }
94 
95 /**
96 * Convert a dword into a double endian string of eight characters
97 * @param int The double word to convert
98 * @param char* The string to write the both endian double word to - It is assumed this is allocated and at least
99 *		eight characters long
100 */
101 void
cd9660_bothendian_dword(uint32_t dw,unsigned char * eightchar)102 cd9660_bothendian_dword(uint32_t dw, unsigned char *eightchar)
103 {
104 	uint32_t le, be;
105 #if BYTE_ORDER == LITTLE_ENDIAN
106 	le = dw;
107 	be = bswap32(dw);
108 #endif
109 #if BYTE_ORDER == BIG_ENDIAN
110 	be = dw;
111 	le = bswap32(dw);
112 #endif
113 	memcpy(eightchar, &le, 4);
114 	memcpy((eightchar+4), &be, 4);
115 }
116 
117 /**
118 * Convert a word into a double endian string of four characters
119 * @param int The word to convert
120 * @param char* The string to write the both endian word to - It is assumed this is allocated and at least
121 *		four characters long
122 */
123 void
cd9660_bothendian_word(uint16_t dw,unsigned char * fourchar)124 cd9660_bothendian_word(uint16_t dw, unsigned char *fourchar)
125 {
126 	uint16_t le, be;
127 #if BYTE_ORDER == LITTLE_ENDIAN
128 	le = dw;
129 	be = bswap16(dw);
130 #endif
131 #if BYTE_ORDER == BIG_ENDIAN
132 	be = dw;
133 	le = bswap16(dw);
134 #endif
135 	memcpy(fourchar, &le, 2);
136 	memcpy((fourchar+2), &be, 2);
137 }
138 
139 void
cd9660_pad_string_spaces(char * str,int len)140 cd9660_pad_string_spaces(char *str, int len)
141 {
142 	int i;
143 
144 	for (i = 0; i < len; i ++) {
145 		if (str[i] == '\0')
146 			str[i] = 0x20;
147 	}
148 }
149 
150 static char
cd9660_compute_gm_offset(time_t tim)151 cd9660_compute_gm_offset(time_t tim)
152 {
153 	struct tm t, gm;
154 
155 	(void)localtime_r(&tim, &t);
156 	(void)gmtime_r(&tim, &gm);
157 	gm.tm_year -= t.tm_year;
158 	gm.tm_yday -= t.tm_yday;
159 	gm.tm_hour -= t.tm_hour;
160 	gm.tm_min  -= t.tm_min;
161 	if (gm.tm_year < 0)
162 		gm.tm_yday = -1;
163 	else if (gm.tm_year > 0)
164 		gm.tm_yday = 1;
165 
166 	return (char)(-(gm.tm_min + 60* (24 * gm.tm_yday + gm.tm_hour)) / 15);
167 }
168 
169 /* Long dates: 17 characters */
170 void
cd9660_time_8426(unsigned char * buf,time_t tim)171 cd9660_time_8426(unsigned char *buf, time_t tim)
172 {
173 	struct tm t;
174 	char temp[18];
175 
176 	(void)localtime_r(&tim, &t);
177 	(void)snprintf(temp, sizeof(temp), "%04i%02i%02i%02i%02i%02i%02i",
178 		1900+(int)t.tm_year,
179 		(int)t.tm_mon+1,
180 		(int)t.tm_mday,
181 		(int)t.tm_hour,
182 		(int)t.tm_min,
183 		(int)t.tm_sec,
184 		0);
185 	(void)memcpy(buf, temp, 16);
186 	buf[16] = cd9660_compute_gm_offset(tim);
187 }
188 
189 /* Short dates: 7 characters */
190 void
cd9660_time_915(unsigned char * buf,time_t tim)191 cd9660_time_915(unsigned char *buf, time_t tim)
192 {
193 	struct tm t;
194 
195 	(void)localtime_r(&tim, &t);
196 	buf[0] = t.tm_year;
197 	buf[1] = t.tm_mon+1;
198 	buf[2] = t.tm_mday;
199 	buf[3] = t.tm_hour;
200 	buf[4] = t.tm_min;
201 	buf[5] = t.tm_sec;
202 	buf[6] = cd9660_compute_gm_offset(tim);
203 }
204