xref: /f-stack/app/redis-5.0.5/src/endianconv.h (revision 572c4311)
1 /* See endianconv.c top comments for more information
2  *
3  * ----------------------------------------------------------------------------
4  *
5  * Copyright (c) 2011-2012, Salvatore Sanfilippo <antirez at gmail dot com>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  *   * Redistributions of source code must retain the above copyright notice,
12  *     this list of conditions and the following disclaimer.
13  *   * Redistributions in binary form must reproduce the above copyright
14  *     notice, this list of conditions and the following disclaimer in the
15  *     documentation and/or other materials provided with the distribution.
16  *   * Neither the name of Redis nor the names of its contributors may be used
17  *     to endorse or promote products derived from this software without
18  *     specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef __ENDIANCONV_H
34 #define __ENDIANCONV_H
35 
36 #include "config.h"
37 #include <stdint.h>
38 
39 void memrev16(void *p);
40 void memrev32(void *p);
41 void memrev64(void *p);
42 uint16_t intrev16(uint16_t v);
43 uint32_t intrev32(uint32_t v);
44 uint64_t intrev64(uint64_t v);
45 
46 /* variants of the function doing the actual conversion only if the target
47  * host is big endian */
48 #if (BYTE_ORDER == LITTLE_ENDIAN)
49 #define memrev16ifbe(p) ((void)(0))
50 #define memrev32ifbe(p) ((void)(0))
51 #define memrev64ifbe(p) ((void)(0))
52 #define intrev16ifbe(v) (v)
53 #define intrev32ifbe(v) (v)
54 #define intrev64ifbe(v) (v)
55 #else
56 #define memrev16ifbe(p) memrev16(p)
57 #define memrev32ifbe(p) memrev32(p)
58 #define memrev64ifbe(p) memrev64(p)
59 #define intrev16ifbe(v) intrev16(v)
60 #define intrev32ifbe(v) intrev32(v)
61 #define intrev64ifbe(v) intrev64(v)
62 #endif
63 
64 /* The functions htonu64() and ntohu64() convert the specified value to
65  * network byte ordering and back. In big endian systems they are no-ops. */
66 #if (BYTE_ORDER == BIG_ENDIAN)
67 #define htonu64(v) (v)
68 #define ntohu64(v) (v)
69 #else
70 #define htonu64(v) intrev64(v)
71 #define ntohu64(v) intrev64(v)
72 #endif
73 
74 #ifdef REDIS_TEST
75 int endianconvTest(int argc, char *argv[]);
76 #endif
77 
78 #endif
79