PortAudio  2.0
pa_endianness.h
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1 #ifndef PA_ENDIANNESS_H
2 #define PA_ENDIANNESS_H
3 /*
4  * $Id$
5  * Portable Audio I/O Library current platform endianness macros
6  *
7  * Based on the Open Source API proposed by Ross Bencina
8  * Copyright (c) 1999-2002 Phil Burk, Ross Bencina
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining
11  * a copy of this software and associated documentation files
12  * (the "Software"), to deal in the Software without restriction,
13  * including without limitation the rights to use, copy, modify, merge,
14  * publish, distribute, sublicense, and/or sell copies of the Software,
15  * and to permit persons to whom the Software is furnished to do so,
16  * subject to the following conditions:
17  *
18  * The above copyright notice and this permission notice shall be
19  * included in all copies or substantial portions of the Software.
20  *
21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
24  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
25  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
26  * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
28  */
29 
30 /*
31  * The text above constitutes the entire PortAudio license; however,
32  * the PortAudio community also makes the following non-binding requests:
33  *
34  * Any person wishing to distribute modifications to the Software is
35  * requested to send the modifications to the original developer so that
36  * they can be incorporated into the canonical version. It is also
37  * requested that these non-binding requests be included along with the
38  * license above.
39  */
40 
61 #ifdef __cplusplus
62 extern "C"
63 {
64 #endif /* __cplusplus */
65 
66 /* If this is an apple, we need to do detect endianness this way */
67 #if defined(__APPLE__)
68  /* we need to do some endian detection that is sensitive to hardware arch */
69  #if defined(__LITTLE_ENDIAN__)
70  #if !defined( PA_LITTLE_ENDIAN )
71  #define PA_LITTLE_ENDIAN
72  #endif
73  #if defined( PA_BIG_ENDIAN )
74  #undef PA_BIG_ENDIAN
75  #endif
76  #else
77  #if !defined( PA_BIG_ENDIAN )
78  #define PA_BIG_ENDIAN
79  #endif
80  #if defined( PA_LITTLE_ENDIAN )
81  #undef PA_LITTLE_ENDIAN
82  #endif
83  #endif
84 #else
85  /* this is not an apple, so first check the existing defines, and, failing that,
86  detect well-known architectures. */
87 
88  #if defined(PA_LITTLE_ENDIAN) || defined(PA_BIG_ENDIAN)
89  /* endianness define has been set externally, such as by autoconf */
90 
91  #if defined(PA_LITTLE_ENDIAN) && defined(PA_BIG_ENDIAN)
92  #error both PA_LITTLE_ENDIAN and PA_BIG_ENDIAN have been defined externally to pa_endianness.h - only one endianness at a time please
93  #endif
94 
95  #else
96  /* endianness define has not been set externally */
97 
98  /* set PA_LITTLE_ENDIAN or PA_BIG_ENDIAN by testing well known platform specific defines */
99 
100  #if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__) || defined(LITTLE_ENDIAN) || defined(__i386) || defined(_M_IX86) || defined(__x86_64__)
101  #define PA_LITTLE_ENDIAN /* win32, assume intel byte order */
102  #else
103  #define PA_BIG_ENDIAN
104  #endif
105  #endif
106 
107  #if !defined(PA_LITTLE_ENDIAN) && !defined(PA_BIG_ENDIAN)
108  /*
109  If the following error is raised, you either need to modify the code above
110  to automatically determine the endianness from other symbols defined on your
111  platform, or define either PA_LITTLE_ENDIAN or PA_BIG_ENDIAN externally.
112  */
113  #error pa_endianness.h was unable to automatically determine the endianness of the target platform
114  #endif
115 
116 #endif
117 
118 
119 /* PA_VALIDATE_ENDIANNESS compares the compile time and runtime endianness,
120  and raises an assertion if they don't match. <assert.h> must be included in
121  the context in which this macro is used.
122 */
123 #if defined(NDEBUG)
124  #define PA_VALIDATE_ENDIANNESS
125 #else
126  #if defined(PA_LITTLE_ENDIAN)
127  #define PA_VALIDATE_ENDIANNESS \
128  { \
129  const long nativeOne = 1; \
130  assert( "PortAudio: compile time and runtime endianness don't match" && (((char *)&nativeOne)[0]) == 1 ); \
131  }
132  #elif defined(PA_BIG_ENDIAN)
133  #define PA_VALIDATE_ENDIANNESS \
134  { \
135  const long nativeOne = 1; \
136  assert( "PortAudio: compile time and runtime endianness don't match" && (((char *)&nativeOne)[0]) == 0 ); \
137  }
138  #endif
139 #endif
140 
141 
142 #ifdef __cplusplus
143 }
144 #endif /* __cplusplus */
145 #endif /* PA_ENDIANNESS_H */