1 /*
2 * Copyright (c) 2009-2021, Google LLC
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 are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of Google LLC nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND 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 Google LLC BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #ifndef UPB_WIRE_SWAP_INTERNAL_H_
29 #define UPB_WIRE_SWAP_INTERNAL_H_
30
31 // Must be last.
32 #include "upb/port/def.inc"
33
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37
_upb_IsLittleEndian(void)38 UPB_INLINE bool _upb_IsLittleEndian(void) {
39 int x = 1;
40 return *(char*)&x == 1;
41 }
42
_upb_BigEndian_Swap32(uint32_t val)43 UPB_INLINE uint32_t _upb_BigEndian_Swap32(uint32_t val) {
44 if (_upb_IsLittleEndian()) return val;
45
46 return ((val & 0xff) << 24) | ((val & 0xff00) << 8) |
47 ((val & 0xff0000) >> 8) | ((val & 0xff000000) >> 24);
48 }
49
_upb_BigEndian_Swap64(uint64_t val)50 UPB_INLINE uint64_t _upb_BigEndian_Swap64(uint64_t val) {
51 if (_upb_IsLittleEndian()) return val;
52
53 return ((uint64_t)_upb_BigEndian_Swap32((uint32_t)val) << 32) |
54 _upb_BigEndian_Swap32((uint32_t)(val >> 32));
55 }
56
57 #ifdef __cplusplus
58 } /* extern "C" */
59 #endif
60
61 #include "upb/port/undef.inc"
62
63 #endif /* UPB_WIRE_SWAP_INTERNAL_H_ */
64