xref: /freebsd/sys/geom/virstor/binstream.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/endian.h>
33 #include <sys/param.h>
34 
35 #include <geom/virstor/binstream.h>
36 
37 /* "Open" a binary stream for reading */
38 void
39 bs_open(bin_stream_t * bs, void *data)
40 {
41 	bs->data = (char *)data;
42 	bs->pos = 0;
43 }
44 
45 /* "Reset" position in binary stream to zero */
46 void
47 bs_reset(bin_stream_t * bs)
48 {
49 	bs->pos = 0;
50 }
51 
52 /* Write a zero-terminated string; return next position */
53 unsigned
54 bs_write_str(bin_stream_t * bs, char *data)
55 {
56 	int		len = 0;
57 	do {
58 		*(bs->data + bs->pos + len) = *data;
59 		len++;
60 	} while (*(data++) != '\0');
61 	bs->pos += len;
62 	return bs->pos;
63 }
64 
65 /* Write an arbitrary buffer; return next position */
66 unsigned
67 bs_write_buf(bin_stream_t * bs, char *data, unsigned data_size)
68 {
69 	unsigned	i;
70 	for (i = 0; i < data_size; i++)
71 		*(bs->data + bs->pos + i) = *(data + i);
72 	bs->pos += data_size;
73 	return bs->pos;
74 }
75 
76 /* Write a 8bit uint; return next position. */
77 unsigned
78 bs_write_u8(bin_stream_t * bs, uint8_t data)
79 {
80 	*((uint8_t *) (bs->data + bs->pos)) = data;
81 	return ++(bs->pos);
82 }
83 
84 /* Write a 16bit uint; return next position. */
85 unsigned
86 bs_write_u16(bin_stream_t * bs, uint16_t data)
87 {
88 	le16enc(bs->data + bs->pos, data);
89 	return (bs->pos += 2);
90 }
91 
92 /* Write a 32bit uint; return next position. */
93 unsigned
94 bs_write_u32(bin_stream_t * bs, uint32_t data)
95 {
96 	le32enc(bs->data + bs->pos, data);
97 	return (bs->pos += 4);
98 }
99 
100 /* Write a 64bit uint; return next position. */
101 unsigned
102 bs_write_u64(bin_stream_t * bs, uint64_t data)
103 {
104 	le64enc(bs->data + bs->pos, data);
105 	return (bs->pos += 8);
106 }
107 
108 /* Read a 8bit uint & return it */
109 uint8_t
110 bs_read_u8(bin_stream_t * bs)
111 {
112 	uint8_t		data = *((uint8_t *) (bs->data + bs->pos));
113 	bs->pos++;
114 	return data;
115 }
116 
117 /*
118  * Read a null-terminated string from stream into a buffer; buf_size is size
119  * of the buffer, including the final \0. Returns buf pointer or NULL if
120  * garbage input.
121  */
122 char*
123 bs_read_str(bin_stream_t * bs, char *buf, unsigned buf_size)
124 {
125 	unsigned	len = 0;
126 	char           *work_buf = buf;
127 	if (buf == NULL || buf_size < 1)
128 		return NULL;
129 	do {
130 		*work_buf = *(bs->data + bs->pos + len);
131 	} while (len++ < buf_size - 1 && *(work_buf++) != '\0');
132 	*(buf + buf_size - 1) = '\0';
133 	bs->pos += len;
134 	return buf;
135 }
136 
137 /* Read an arbitrary buffer. */
138 void
139 bs_read_buf(bin_stream_t * bs, char *buf, unsigned buf_size)
140 {
141 	unsigned	i;
142 	for (i = 0; i < buf_size; i++)
143 		*(buf + i) = *(bs->data + bs->pos + i);
144 	bs->pos += buf_size;
145 }
146 
147 /* Read a 16bit uint & return it */
148 uint16_t
149 bs_read_u16(bin_stream_t * bs)
150 {
151 	uint16_t	data = le16dec(bs->data + bs->pos);
152 	bs->pos += 2;
153 	return data;
154 }
155 
156 /* Read a 32bit uint & return it */
157 uint32_t
158 bs_read_u32(bin_stream_t * bs)
159 {
160 	uint32_t	data = le32dec(bs->data + bs->pos);
161 	bs->pos += 4;
162 	return data;
163 }
164 
165 /* Read a 64bit uint & return it */
166 uint64_t
167 bs_read_u64(bin_stream_t * bs)
168 {
169 	uint64_t	data = le64dec(bs->data + bs->pos);
170 	bs->pos += 8;
171 	return data;
172 }
173