archive_endian.h revision 358088 
1/*-
2 * Copyright (c) 2002 Thomas Moestl <tmm@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/11/contrib/libarchive/libarchive/archive_endian.h 358088 2020-02-19 01:50:47Z mm $
27 *
28 * Borrowed from FreeBSD's <sys/endian.h>
29 */
30
31#ifndef ARCHIVE_ENDIAN_H_INCLUDED
32#define ARCHIVE_ENDIAN_H_INCLUDED
33
34/* Note:  This is a purely internal header! */
35/* Do not use this outside of libarchive internal code! */
36
37#ifndef __LIBARCHIVE_BUILD
38#error This header is only to be used internally to libarchive.
39#endif
40
41/*
42 * Disabling inline keyword for compilers known to choke on it:
43 * - Watcom C++ in C code.  (For any version?)
44 * - SGI MIPSpro
45 * - Microsoft Visual C++ 6.0 (supposedly newer versions too)
46 * - IBM VisualAge 6 (XL v6)
47 * - Sun WorkShop C (SunPro) before 5.9
48 */
49#if defined(__WATCOMC__) || defined(__sgi) || defined(__hpux) || defined(__BORLANDC__)
50#define	inline
51#elif defined(__IBMC__) && __IBMC__ < 700
52#define	inline
53#elif defined(__SUNPRO_C) && __SUNPRO_C < 0x590
54#define inline
55#elif defined(_MSC_VER) || defined(__osf__)
56#define inline __inline
57#endif
58
59/* Alignment-agnostic encode/decode bytestream to/from little/big endian. */
60
61static inline uint16_t
62archive_be16dec(const void *pp)
63{
64	unsigned char const *p = (unsigned char const *)pp;
65
66	/* Store into unsigned temporaries before left shifting, to avoid
67	promotion to signed int and then left shifting into the sign bit,
68	which is undefined behaviour. */
69	unsigned int p1 = p[1];
70	unsigned int p0 = p[0];
71
72	return ((p0 << 8) | p1);
73}
74
75static inline uint32_t
76archive_be32dec(const void *pp)
77{
78	unsigned char const *p = (unsigned char const *)pp;
79
80	/* Store into unsigned temporaries before left shifting, to avoid
81	promotion to signed int and then left shifting into the sign bit,
82	which is undefined behaviour. */
83	unsigned int p3 = p[3];
84	unsigned int p2 = p[2];
85	unsigned int p1 = p[1];
86	unsigned int p0 = p[0];
87
88	return ((p0 << 24) | (p1 << 16) | (p2 << 8) | p3);
89}
90
91static inline uint64_t
92archive_be64dec(const void *pp)
93{
94	unsigned char const *p = (unsigned char const *)pp;
95
96	return (((uint64_t)archive_be32dec(p) << 32) | archive_be32dec(p + 4));
97}
98
99static inline uint16_t
100archive_le16dec(const void *pp)
101{
102	unsigned char const *p = (unsigned char const *)pp;
103
104	/* Store into unsigned temporaries before left shifting, to avoid
105	promotion to signed int and then left shifting into the sign bit,
106	which is undefined behaviour. */
107	unsigned int p1 = p[1];
108	unsigned int p0 = p[0];
109
110	return ((p1 << 8) | p0);
111}
112
113static inline uint32_t
114archive_le32dec(const void *pp)
115{
116	unsigned char const *p = (unsigned char const *)pp;
117
118	/* Store into unsigned temporaries before left shifting, to avoid
119	promotion to signed int and then left shifting into the sign bit,
120	which is undefined behaviour. */
121	unsigned int p3 = p[3];
122	unsigned int p2 = p[2];
123	unsigned int p1 = p[1];
124	unsigned int p0 = p[0];
125
126	return ((p3 << 24) | (p2 << 16) | (p1 << 8) | p0);
127}
128
129static inline uint64_t
130archive_le64dec(const void *pp)
131{
132	unsigned char const *p = (unsigned char const *)pp;
133
134	return (((uint64_t)archive_le32dec(p + 4) << 32) | archive_le32dec(p));
135}
136
137static inline void
138archive_be16enc(void *pp, uint16_t u)
139{
140	unsigned char *p = (unsigned char *)pp;
141
142	p[0] = (u >> 8) & 0xff;
143	p[1] = u & 0xff;
144}
145
146static inline void
147archive_be32enc(void *pp, uint32_t u)
148{
149	unsigned char *p = (unsigned char *)pp;
150
151	p[0] = (u >> 24) & 0xff;
152	p[1] = (u >> 16) & 0xff;
153	p[2] = (u >> 8) & 0xff;
154	p[3] = u & 0xff;
155}
156
157static inline void
158archive_be64enc(void *pp, uint64_t u)
159{
160	unsigned char *p = (unsigned char *)pp;
161
162	archive_be32enc(p, (uint32_t)(u >> 32));
163	archive_be32enc(p + 4, (uint32_t)(u & 0xffffffff));
164}
165
166static inline void
167archive_le16enc(void *pp, uint16_t u)
168{
169	unsigned char *p = (unsigned char *)pp;
170
171	p[0] = u & 0xff;
172	p[1] = (u >> 8) & 0xff;
173}
174
175static inline void
176archive_le32enc(void *pp, uint32_t u)
177{
178	unsigned char *p = (unsigned char *)pp;
179
180	p[0] = u & 0xff;
181	p[1] = (u >> 8) & 0xff;
182	p[2] = (u >> 16) & 0xff;
183	p[3] = (u >> 24) & 0xff;
184}
185
186static inline void
187archive_le64enc(void *pp, uint64_t u)
188{
189	unsigned char *p = (unsigned char *)pp;
190
191	archive_le32enc(p, (uint32_t)(u & 0xffffffff));
192	archive_le32enc(p + 4, (uint32_t)(u >> 32));
193}
194
195#endif
196