xref: /freebsd/sys/geom/virstor/binstream.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005 Ivan Voras <ivoras@gmail.com>
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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 // $Id: binstream.c,v 1.1 2006/07/05 10:47:54 ivoras Exp $
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/endian.h>
35 #include <sys/param.h>
36 
37 #include <geom/virstor/binstream.h>
38 
39 
40 /* "Open" a binary stream for reading */
41 void
42 bs_open(bin_stream_t * bs, void *data)
43 {
44 	bs->data = (char *)data;
45 	bs->pos = 0;
46 }
47 
48 
49 /* "Reset" position in binary stream to zero */
50 void
51 bs_reset(bin_stream_t * bs)
52 {
53 	bs->pos = 0;
54 }
55 
56 /* Write a zero-terminated string; return next position */
57 unsigned
58 bs_write_str(bin_stream_t * bs, char *data)
59 {
60 	int		len = 0;
61 	do {
62 		*(bs->data + bs->pos + len) = *data;
63 		len++;
64 	} while (*(data++) != '\0');
65 	bs->pos += len;
66 	return bs->pos;
67 }
68 
69 
70 /* Write an arbitrary buffer; return next position */
71 unsigned
72 bs_write_buf(bin_stream_t * bs, char *data, unsigned data_size)
73 {
74 	unsigned	i;
75 	for (i = 0; i < data_size; i++)
76 		*(bs->data + bs->pos + i) = *(data + i);
77 	bs->pos += data_size;
78 	return bs->pos;
79 }
80 
81 
82 /* Write a 8bit uint; return next position. */
83 unsigned
84 bs_write_u8(bin_stream_t * bs, uint8_t data)
85 {
86 	*((uint8_t *) (bs->data + bs->pos)) = data;
87 	return ++(bs->pos);
88 }
89 
90 
91 /* Write a 16bit uint; return next position. */
92 unsigned
93 bs_write_u16(bin_stream_t * bs, uint16_t data)
94 {
95 	le16enc(bs->data + bs->pos, data);
96 	return (bs->pos += 2);
97 }
98 
99 
100 /* Write a 32bit uint; return next position. */
101 unsigned
102 bs_write_u32(bin_stream_t * bs, uint32_t data)
103 {
104 	le32enc(bs->data + bs->pos, data);
105 	return (bs->pos += 4);
106 }
107 
108 
109 /* Write a 64bit uint; return next position. */
110 unsigned
111 bs_write_u64(bin_stream_t * bs, uint64_t data)
112 {
113 	le64enc(bs->data + bs->pos, data);
114 	return (bs->pos += 8);
115 }
116 
117 
118 /* Read a 8bit uint & return it */
119 uint8_t
120 bs_read_u8(bin_stream_t * bs)
121 {
122 	uint8_t		data = *((uint8_t *) (bs->data + bs->pos));
123 	bs->pos++;
124 	return data;
125 }
126 
127 
128 /*
129  * Read a null-terminated string from stream into a buffer; buf_size is size
130  * of the buffer, including the final \0. Returns buf pointer or NULL if
131  * garbage input.
132  */
133 char*
134 bs_read_str(bin_stream_t * bs, char *buf, unsigned buf_size)
135 {
136 	unsigned	len = 0;
137 	char           *work_buf = buf;
138 	if (buf == NULL || buf_size < 1)
139 		return NULL;
140 	do {
141 		*work_buf = *(bs->data + bs->pos + len);
142 	} while (len++ < buf_size - 1 && *(work_buf++) != '\0');
143 	*(buf + buf_size - 1) = '\0';
144 	bs->pos += len;
145 	return buf;
146 }
147 
148 
149 /* Read an arbitrary buffer. */
150 void
151 bs_read_buf(bin_stream_t * bs, char *buf, unsigned buf_size)
152 {
153 	unsigned	i;
154 	for (i = 0; i < buf_size; i++)
155 		*(buf + i) = *(bs->data + bs->pos + i);
156 	bs->pos += buf_size;
157 }
158 
159 
160 /* Read a 16bit uint & return it */
161 uint16_t
162 bs_read_u16(bin_stream_t * bs)
163 {
164 	uint16_t	data = le16dec(bs->data + bs->pos);
165 	bs->pos += 2;
166 	return data;
167 }
168 
169 
170 /* Read a 32bit uint & return it */
171 uint32_t
172 bs_read_u32(bin_stream_t * bs)
173 {
174 	uint32_t	data = le32dec(bs->data + bs->pos);
175 	bs->pos += 4;
176 	return data;
177 }
178 
179 
180 /* Read a 64bit uint & return it */
181 uint64_t
182 bs_read_u64(bin_stream_t * bs)
183 {
184 	uint64_t	data = le64dec(bs->data + bs->pos);
185 	bs->pos += 8;
186 	return data;
187 }
188