Mercurial > sdl-ios-xcode
annotate include/SDL_endian.h @ 537:77b05010bb33
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author | Sam Lantinga <slouken@libsdl.org> |
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date | Sat, 09 Nov 2002 05:51:13 +0000 |
parents | 9154ec9ca3d2 |
children | b8d311d90021 |
rev | line source |
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0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
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Updated copyright information for 2002
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3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga |
0 | 4 |
5 This library is free software; you can redistribute it and/or | |
6 modify it under the terms of the GNU Library General Public | |
7 License as published by the Free Software Foundation; either | |
8 version 2 of the License, or (at your option) any later version. | |
9 | |
10 This library is distributed in the hope that it will be useful, | |
11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
13 Library General Public License for more details. | |
14 | |
15 You should have received a copy of the GNU Library General Public | |
16 License along with this library; if not, write to the Free | |
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | |
19 Sam Lantinga | |
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Updated the headers with the correct e-mail address
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20 slouken@libsdl.org |
0 | 21 */ |
22 | |
23 #ifdef SAVE_RCSID | |
24 static char rcsid = | |
25 "@(#) $Id$"; | |
26 #endif | |
27 | |
28 /* Functions for reading and writing endian-specific values */ | |
29 | |
30 #ifndef _SDL_endian_h | |
31 #define _SDL_endian_h | |
32 | |
33 /* These functions read and write data of the specified endianness, | |
34 dynamically translating to the host machine endianness. | |
35 | |
36 e.g.: If you want to read a 16 bit value on big-endian machine from | |
37 an open file containing little endian values, you would use: | |
38 value = SDL_ReadLE16(rp); | |
39 Note that the read/write functions use SDL_RWops pointers | |
40 instead of FILE pointers. This allows you to read and write | |
41 endian values from large chunks of memory as well as files | |
42 and other data sources. | |
43 */ | |
44 | |
45 #include <stdio.h> | |
46 | |
47 #include "SDL_types.h" | |
48 #include "SDL_rwops.h" | |
49 #include "SDL_byteorder.h" | |
50 | |
51 #include "begin_code.h" | |
52 /* Set up for C function definitions, even when using C++ */ | |
53 #ifdef __cplusplus | |
54 extern "C" { | |
55 #endif | |
56 | |
57 /* The macros used to swap values */ | |
58 /* Try to use superfast macros on systems that support them */ | |
59 #ifdef linux | |
60 #include <asm/byteorder.h> | |
61 #ifdef __arch__swab16 | |
62 #define SDL_Swap16 __arch__swab16 | |
63 #endif | |
64 #ifdef __arch__swab32 | |
65 #define SDL_Swap32 __arch__swab32 | |
66 #endif | |
67 #endif /* linux */ | |
68 /* Use inline functions for compilers that support them, and static | |
69 functions for those that do not. Because these functions become | |
70 static for compilers that do not support inline functions, this | |
71 header should only be included in files that actually use them. | |
72 */ | |
73 #ifndef SDL_Swap16 | |
74 static __inline__ Uint16 SDL_Swap16(Uint16 D) { | |
75 return((D<<8)|(D>>8)); | |
76 } | |
77 #endif | |
78 #ifndef SDL_Swap32 | |
79 static __inline__ Uint32 SDL_Swap32(Uint32 D) { | |
80 return((D<<24)|((D<<8)&0x00FF0000)|((D>>8)&0x0000FF00)|(D>>24)); | |
81 } | |
82 #endif | |
83 #ifdef SDL_HAS_64BIT_TYPE | |
84 #ifndef SDL_Swap64 | |
85 static __inline__ Uint64 SDL_Swap64(Uint64 val) { | |
86 Uint32 hi, lo; | |
87 | |
88 /* Separate into high and low 32-bit values and swap them */ | |
89 lo = (Uint32)(val&0xFFFFFFFF); | |
90 val >>= 32; | |
91 hi = (Uint32)(val&0xFFFFFFFF); | |
92 val = SDL_Swap32(lo); | |
93 val <<= 32; | |
94 val |= SDL_Swap32(hi); | |
95 return(val); | |
96 } | |
97 #endif | |
98 #else | |
99 #ifndef SDL_Swap64 | |
100 /* This is mainly to keep compilers from complaining in SDL code. | |
101 If there is no real 64-bit datatype, then compilers will complain about | |
102 the fake 64-bit datatype that SDL provides when it compiles user code. | |
103 */ | |
104 #define SDL_Swap64(X) (X) | |
105 #endif | |
106 #endif /* SDL_HAS_64BIT_TYPE */ | |
107 | |
108 | |
109 /* Byteswap item from the specified endianness to the native endianness */ | |
110 #if SDL_BYTEORDER == SDL_LIL_ENDIAN | |
111 #define SDL_SwapLE16(X) (X) | |
112 #define SDL_SwapLE32(X) (X) | |
113 #define SDL_SwapLE64(X) (X) | |
114 #define SDL_SwapBE16(X) SDL_Swap16(X) | |
115 #define SDL_SwapBE32(X) SDL_Swap32(X) | |
116 #define SDL_SwapBE64(X) SDL_Swap64(X) | |
117 #else | |
118 #define SDL_SwapLE16(X) SDL_Swap16(X) | |
119 #define SDL_SwapLE32(X) SDL_Swap32(X) | |
120 #define SDL_SwapLE64(X) SDL_Swap64(X) | |
121 #define SDL_SwapBE16(X) (X) | |
122 #define SDL_SwapBE32(X) (X) | |
123 #define SDL_SwapBE64(X) (X) | |
124 #endif | |
125 | |
126 /* Read an item of the specified endianness and return in native format */ | |
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127 extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops *src); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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128 extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops *src); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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129 extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops *src); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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130 extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops *src); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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131 extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops *src); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
132 extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops *src); |
0 | 133 |
134 /* Write an item of native format to the specified endianness */ | |
337
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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135 extern DECLSPEC int SDLCALL SDL_WriteLE16(SDL_RWops *dst, Uint16 value); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
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136 extern DECLSPEC int SDLCALL SDL_WriteBE16(SDL_RWops *dst, Uint16 value); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
137 extern DECLSPEC int SDLCALL SDL_WriteLE32(SDL_RWops *dst, Uint32 value); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
138 extern DECLSPEC int SDLCALL SDL_WriteBE32(SDL_RWops *dst, Uint32 value); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
139 extern DECLSPEC int SDLCALL SDL_WriteLE64(SDL_RWops *dst, Uint64 value); |
9154ec9ca3d2
Explicitly specify the SDL API calling convention (C by default)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
140 extern DECLSPEC int SDLCALL SDL_WriteBE64(SDL_RWops *dst, Uint64 value); |
0 | 141 |
142 | |
143 /* Ends C function definitions when using C++ */ | |
144 #ifdef __cplusplus | |
145 } | |
146 #endif | |
147 #include "close_code.h" | |
148 | |
149 #endif /* _SDL_endian_h */ |