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author Paper <paper@tflc.us>
date Mon, 05 Jan 2026 02:15:46 -0500
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0:e9bb126753e7 1:20d02a178406
1 /*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20 */
21
22 /**
23 * # CategoryEndian
24 *
25 * Functions converting endian-specific values to different byte orders.
26 *
27 * These functions either unconditionally swap byte order (SDL_Swap16,
28 * SDL_Swap32, SDL_Swap64, SDL_SwapFloat), or they swap to/from the system's
29 * native byte order (SDL_Swap16LE, SDL_Swap16BE, SDL_Swap32LE, SDL_Swap32BE,
30 * SDL_Swap32LE, SDL_Swap32BE, SDL_SwapFloatLE, SDL_SwapFloatBE). In the
31 * latter case, the functionality is provided by macros that become no-ops if
32 * a swap isn't necessary: on an x86 (littleendian) processor, SDL_Swap32LE
33 * does nothing, but SDL_Swap32BE reverses the bytes of the data. On a PowerPC
34 * processor (bigendian), the macros behavior is reversed.
35 *
36 * The swap routines are inline functions, and attempt to use compiler
37 * intrinsics, inline assembly, and other magic to make byteswapping
38 * efficient.
39 */
40
41 #ifndef SDL_endian_h_
42 #define SDL_endian_h_
43
44 #include <SDL3/SDL_stdinc.h>
45
46 #if defined(_MSC_VER) && (_MSC_VER >= 1400)
47 /* As of Clang 11, '_m_prefetchw' is conflicting with the winnt.h's version,
48 so we define the needed '_m_prefetch' here as a pseudo-header, until the issue is fixed. */
49 #if defined(__clang__) && !SDL_HAS_BUILTIN(_m_prefetch)
50 #ifndef __PRFCHWINTRIN_H
51 #define __PRFCHWINTRIN_H
52 static __inline__ void __attribute__((__always_inline__, __nodebug__))
53 _m_prefetch(void *__P)
54 {
55 __builtin_prefetch(__P, 0, 3 /* _MM_HINT_T0 */);
56 }
57 #endif /* __PRFCHWINTRIN_H */
58 #endif /* __clang__ */
59
60 #include <intrin.h>
61 #endif
62
63 /**
64 * \name The two types of endianness
65 */
66 /* @{ */
67
68
69 /**
70 * A value to represent littleendian byteorder.
71 *
72 * This is used with the preprocessor macro SDL_BYTEORDER, to determine a
73 * platform's byte ordering:
74 *
75 * ```c
76 * #if SDL_BYTEORDER == SDL_LIL_ENDIAN
77 * SDL_Log("This system is littleendian.");
78 * #endif
79 * ```
80 *
81 * \since This macro is available since SDL 3.2.0.
82 *
83 * \sa SDL_BYTEORDER
84 * \sa SDL_BIG_ENDIAN
85 */
86 #define SDL_LIL_ENDIAN 1234
87
88 /**
89 * A value to represent bigendian byteorder.
90 *
91 * This is used with the preprocessor macro SDL_BYTEORDER, to determine a
92 * platform's byte ordering:
93 *
94 * ```c
95 * #if SDL_BYTEORDER == SDL_BIG_ENDIAN
96 * SDL_Log("This system is bigendian.");
97 * #endif
98 * ```
99 *
100 * \since This macro is available since SDL 3.2.0.
101 *
102 * \sa SDL_BYTEORDER
103 * \sa SDL_LIL_ENDIAN
104 */
105 #define SDL_BIG_ENDIAN 4321
106
107 /* @} */
108
109 #ifndef SDL_BYTEORDER
110 #ifdef SDL_WIKI_DOCUMENTATION_SECTION
111
112 /**
113 * A macro that reports the target system's byte order.
114 *
115 * This is set to either SDL_LIL_ENDIAN or SDL_BIG_ENDIAN (and maybe other
116 * values in the future, if something else becomes popular). This can be
117 * tested with the preprocessor, so decisions can be made at compile time.
118 *
119 * ```c
120 * #if SDL_BYTEORDER == SDL_BIG_ENDIAN
121 * SDL_Log("This system is bigendian.");
122 * #endif
123 * ```
124 *
125 * \since This macro is available since SDL 3.2.0.
126 *
127 * \sa SDL_LIL_ENDIAN
128 * \sa SDL_BIG_ENDIAN
129 */
130 #define SDL_BYTEORDER SDL_LIL_ENDIAN___or_maybe___SDL_BIG_ENDIAN
131 #elif defined(SDL_PLATFORM_LINUX) || defined(__GLIBC__)
132 #include <endian.h>
133 #define SDL_BYTEORDER __BYTE_ORDER
134 #elif defined(SDL_PLATFORM_SOLARIS)
135 #include <sys/byteorder.h>
136 #if defined(_LITTLE_ENDIAN)
137 #define SDL_BYTEORDER SDL_LIL_ENDIAN
138 #elif defined(_BIG_ENDIAN)
139 #define SDL_BYTEORDER SDL_BIG_ENDIAN
140 #else
141 #error Unsupported endianness
142 #endif
143 #elif defined(SDL_PLATFORM_OPENBSD) || defined(__DragonFly__)
144 #include <endian.h>
145 #define SDL_BYTEORDER BYTE_ORDER
146 #elif defined(SDL_PLATFORM_FREEBSD) || defined(SDL_PLATFORM_NETBSD)
147 #include <sys/endian.h>
148 #define SDL_BYTEORDER BYTE_ORDER
149 /* predefs from newer gcc and clang versions: */
150 #elif defined(__ORDER_LITTLE_ENDIAN__) && defined(__ORDER_BIG_ENDIAN__) && defined(__BYTE_ORDER__)
151 #if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
152 #define SDL_BYTEORDER SDL_LIL_ENDIAN
153 #elif (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
154 #define SDL_BYTEORDER SDL_BIG_ENDIAN
155 #else
156 #error Unsupported endianness
157 #endif /**/
158 #else
159 #if defined(__hppa__) || \
160 defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \
161 (defined(__MIPS__) && defined(__MIPSEB__)) || \
162 defined(__ppc__) || defined(__POWERPC__) || defined(__powerpc__) || defined(__PPC__) || \
163 defined(__sparc__) || defined(__sparc)
164 #define SDL_BYTEORDER SDL_BIG_ENDIAN
165 #else
166 #define SDL_BYTEORDER SDL_LIL_ENDIAN
167 #endif
168 #endif /* SDL_PLATFORM_LINUX */
169 #endif /* !SDL_BYTEORDER */
170
171 #ifndef SDL_FLOATWORDORDER
172 #ifdef SDL_WIKI_DOCUMENTATION_SECTION
173
174 /**
175 * A macro that reports the target system's floating point word order.
176 *
177 * This is set to either SDL_LIL_ENDIAN or SDL_BIG_ENDIAN (and maybe other
178 * values in the future, if something else becomes popular). This can be
179 * tested with the preprocessor, so decisions can be made at compile time.
180 *
181 * ```c
182 * #if SDL_FLOATWORDORDER == SDL_BIG_ENDIAN
183 * SDL_Log("This system's floats are bigendian.");
184 * #endif
185 * ```
186 *
187 * \since This macro is available since SDL 3.2.0.
188 *
189 * \sa SDL_LIL_ENDIAN
190 * \sa SDL_BIG_ENDIAN
191 */
192 #define SDL_FLOATWORDORDER SDL_LIL_ENDIAN___or_maybe___SDL_BIG_ENDIAN
193 /* predefs from newer gcc versions: */
194 #elif defined(__ORDER_LITTLE_ENDIAN__) && defined(__ORDER_BIG_ENDIAN__) && defined(__FLOAT_WORD_ORDER__)
195 #if (__FLOAT_WORD_ORDER__ == __ORDER_LITTLE_ENDIAN__)
196 #define SDL_FLOATWORDORDER SDL_LIL_ENDIAN
197 #elif (__FLOAT_WORD_ORDER__ == __ORDER_BIG_ENDIAN__)
198 #define SDL_FLOATWORDORDER SDL_BIG_ENDIAN
199 #else
200 #error Unsupported endianness
201 #endif /**/
202 #elif defined(__MAVERICK__)
203 /* For Maverick, float words are always little-endian. */
204 #define SDL_FLOATWORDORDER SDL_LIL_ENDIAN
205 #elif (defined(__arm__) || defined(__thumb__)) && !defined(__VFP_FP__) && !defined(__ARM_EABI__)
206 /* For FPA, float words are always big-endian. */
207 #define SDL_FLOATWORDORDER SDL_BIG_ENDIAN
208 #else
209 /* By default, assume that floats words follow the memory system mode. */
210 #define SDL_FLOATWORDORDER SDL_BYTEORDER
211 #endif /* __FLOAT_WORD_ORDER__ */
212 #endif /* !SDL_FLOATWORDORDER */
213
214
215 #include <SDL3/SDL_begin_code.h>
216 /* Set up for C function definitions, even when using C++ */
217 #ifdef __cplusplus
218 extern "C" {
219 #endif
220
221 /* various modern compilers may have builtin swap */
222 #if defined(__GNUC__) || defined(__clang__)
223 # define HAS_BUILTIN_BSWAP16 (SDL_HAS_BUILTIN(__builtin_bswap16)) || \
224 (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))
225 # define HAS_BUILTIN_BSWAP32 (SDL_HAS_BUILTIN(__builtin_bswap32)) || \
226 (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
227 # define HAS_BUILTIN_BSWAP64 (SDL_HAS_BUILTIN(__builtin_bswap64)) || \
228 (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
229
230 /* this one is broken */
231 # define HAS_BROKEN_BSWAP (__GNUC__ == 2 && __GNUC_MINOR__ <= 95)
232 #else
233 # define HAS_BUILTIN_BSWAP16 0
234 # define HAS_BUILTIN_BSWAP32 0
235 # define HAS_BUILTIN_BSWAP64 0
236 # define HAS_BROKEN_BSWAP 0
237 #endif
238
239 /* Byte swap 16-bit integer. */
240 #ifndef SDL_WIKI_DOCUMENTATION_SECTION
241 #if HAS_BUILTIN_BSWAP16
242 #define SDL_Swap16(x) __builtin_bswap16(x)
243 #elif (defined(_MSC_VER) && (_MSC_VER >= 1400)) && !defined(__ICL)
244 #pragma intrinsic(_byteswap_ushort)
245 #define SDL_Swap16(x) _byteswap_ushort(x)
246 #elif defined(__i386__) && !HAS_BROKEN_BSWAP
247 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
248 {
249 __asm__("xchgb %b0,%h0": "=q"(x):"0"(x));
250 return x;
251 }
252 #elif defined(__x86_64__)
253 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
254 {
255 __asm__("xchgb %b0,%h0": "=abcd"(x):"0"(x));
256 return x;
257 }
258 #elif (defined(__powerpc__) || defined(__ppc__))
259 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
260 {
261 int result;
262
263 __asm__("rlwimi %0,%2,8,16,23": "=&r"(result):"0"(x >> 8), "r"(x));
264 return (Uint16)result;
265 }
266 #elif (defined(__m68k__) && !defined(__mcoldfire__))
267 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
268 {
269 __asm__("rorw #8,%0": "=d"(x): "0"(x):"cc");
270 return x;
271 }
272 #elif defined(__WATCOMC__) && defined(__386__)
273 extern __inline Uint16 SDL_Swap16(Uint16);
274 #pragma aux SDL_Swap16 = \
275 "xchg al, ah" \
276 parm [ax] \
277 modify [ax];
278 #else
279 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
280 {
281 return SDL_static_cast(Uint16, ((x << 8) | (x >> 8)));
282 }
283 #endif
284 #endif
285
286 /* Byte swap 32-bit integer. */
287 #ifndef SDL_WIKI_DOCUMENTATION_SECTION
288 #if HAS_BUILTIN_BSWAP32
289 #define SDL_Swap32(x) __builtin_bswap32(x)
290 #elif (defined(_MSC_VER) && (_MSC_VER >= 1400)) && !defined(__ICL)
291 #pragma intrinsic(_byteswap_ulong)
292 #define SDL_Swap32(x) _byteswap_ulong(x)
293 #elif defined(__i386__) && !HAS_BROKEN_BSWAP
294 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
295 {
296 __asm__("bswap %0": "=r"(x):"0"(x));
297 return x;
298 }
299 #elif defined(__x86_64__)
300 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
301 {
302 __asm__("bswapl %0": "=r"(x):"0"(x));
303 return x;
304 }
305 #elif (defined(__powerpc__) || defined(__ppc__))
306 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
307 {
308 Uint32 result;
309
310 __asm__("rlwimi %0,%2,24,16,23": "=&r"(result): "0" (x>>24), "r"(x));
311 __asm__("rlwimi %0,%2,8,8,15" : "=&r"(result): "0" (result), "r"(x));
312 __asm__("rlwimi %0,%2,24,0,7" : "=&r"(result): "0" (result), "r"(x));
313 return result;
314 }
315 #elif (defined(__m68k__) && !defined(__mcoldfire__))
316 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
317 {
318 __asm__("rorw #8,%0\n\tswap %0\n\trorw #8,%0": "=d"(x): "0"(x):"cc");
319 return x;
320 }
321 #elif defined(__WATCOMC__) && defined(__386__)
322 extern __inline Uint32 SDL_Swap32(Uint32);
323 #pragma aux SDL_Swap32 = \
324 "bswap eax" \
325 parm [eax] \
326 modify [eax];
327 #else
328 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
329 {
330 return SDL_static_cast(Uint32, ((x << 24) | ((x << 8) & 0x00FF0000) |
331 ((x >> 8) & 0x0000FF00) | (x >> 24)));
332 }
333 #endif
334 #endif
335
336 /* Byte swap 64-bit integer. */
337 #ifndef SDL_WIKI_DOCUMENTATION_SECTION
338 #if HAS_BUILTIN_BSWAP64
339 #define SDL_Swap64(x) __builtin_bswap64(x)
340 #elif (defined(_MSC_VER) && (_MSC_VER >= 1400)) && !defined(__ICL)
341 #pragma intrinsic(_byteswap_uint64)
342 #define SDL_Swap64(x) _byteswap_uint64(x)
343 #elif defined(__i386__) && !HAS_BROKEN_BSWAP
344 SDL_FORCE_INLINE Uint64 SDL_Swap64(Uint64 x)
345 {
346 union {
347 struct {
348 Uint32 a, b;
349 } s;
350 Uint64 u;
351 } v;
352 v.u = x;
353 __asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
354 : "=r"(v.s.a), "=r"(v.s.b)
355 : "0" (v.s.a), "1"(v.s.b));
356 return v.u;
357 }
358 #elif defined(__x86_64__)
359 SDL_FORCE_INLINE Uint64 SDL_Swap64(Uint64 x)
360 {
361 __asm__("bswapq %0": "=r"(x):"0"(x));
362 return x;
363 }
364 #elif defined(__WATCOMC__) && defined(__386__)
365 extern __inline Uint64 SDL_Swap64(Uint64);
366 #pragma aux SDL_Swap64 = \
367 "bswap eax" \
368 "bswap edx" \
369 "xchg eax,edx" \
370 parm [eax edx] \
371 modify [eax edx];
372 #else
373 SDL_FORCE_INLINE Uint64 SDL_Swap64(Uint64 x)
374 {
375 Uint32 hi, lo;
376
377 /* Separate into high and low 32-bit values and swap them */
378 lo = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
379 x >>= 32;
380 hi = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
381 x = SDL_Swap32(lo);
382 x <<= 32;
383 x |= SDL_Swap32(hi);
384 return (x);
385 }
386 #endif
387 #endif
388
389 /**
390 * Byte-swap a floating point number.
391 *
392 * This will always byte-swap the value, whether it's currently in the native
393 * byteorder of the system or not. You should use SDL_SwapFloatLE or
394 * SDL_SwapFloatBE instead, in most cases.
395 *
396 * Note that this is a forced-inline function in a header, and not a public
397 * API function available in the SDL library (which is to say, the code is
398 * embedded in the calling program and the linker and dynamic loader will not
399 * be able to find this function inside SDL itself).
400 *
401 * \param x the value to byte-swap.
402 * \returns x, with its bytes in the opposite endian order.
403 *
404 * \threadsafety It is safe to call this function from any thread.
405 *
406 * \since This function is available since SDL 3.2.0.
407 */
408 SDL_FORCE_INLINE float SDL_SwapFloat(float x)
409 {
410 union {
411 float f;
412 Uint32 ui32;
413 } swapper;
414 swapper.f = x;
415 swapper.ui32 = SDL_Swap32(swapper.ui32);
416 return swapper.f;
417 }
418
419 /* remove extra macros */
420 #undef HAS_BROKEN_BSWAP
421 #undef HAS_BUILTIN_BSWAP16
422 #undef HAS_BUILTIN_BSWAP32
423 #undef HAS_BUILTIN_BSWAP64
424
425
426 #ifdef SDL_WIKI_DOCUMENTATION_SECTION
427
428 /**
429 * Byte-swap an unsigned 16-bit number.
430 *
431 * This will always byte-swap the value, whether it's currently in the native
432 * byteorder of the system or not. You should use SDL_Swap16LE or SDL_Swap16BE
433 * instead, in most cases.
434 *
435 * Note that this is a forced-inline function in a header, and not a public
436 * API function available in the SDL library (which is to say, the code is
437 * embedded in the calling program and the linker and dynamic loader will not
438 * be able to find this function inside SDL itself).
439 *
440 * \param x the value to byte-swap.
441 * \returns `x`, with its bytes in the opposite endian order.
442 *
443 * \threadsafety It is safe to call this function from any thread.
444 *
445 * \since This function is available since SDL 3.2.0.
446 */
447 SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x) { return x_but_byteswapped; }
448
449 /**
450 * Byte-swap an unsigned 32-bit number.
451 *
452 * This will always byte-swap the value, whether it's currently in the native
453 * byteorder of the system or not. You should use SDL_Swap32LE or SDL_Swap32BE
454 * instead, in most cases.
455 *
456 * Note that this is a forced-inline function in a header, and not a public
457 * API function available in the SDL library (which is to say, the code is
458 * embedded in the calling program and the linker and dynamic loader will not
459 * be able to find this function inside SDL itself).
460 *
461 * \param x the value to byte-swap.
462 * \returns `x`, with its bytes in the opposite endian order.
463 *
464 * \threadsafety It is safe to call this function from any thread.
465 *
466 * \since This function is available since SDL 3.2.0.
467 */
468 SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x) { return x_but_byteswapped; }
469
470 /**
471 * Byte-swap an unsigned 64-bit number.
472 *
473 * This will always byte-swap the value, whether it's currently in the native
474 * byteorder of the system or not. You should use SDL_Swap64LE or SDL_Swap64BE
475 * instead, in most cases.
476 *
477 * Note that this is a forced-inline function in a header, and not a public
478 * API function available in the SDL library (which is to say, the code is
479 * embedded in the calling program and the linker and dynamic loader will not
480 * be able to find this function inside SDL itself).
481 *
482 * \param x the value to byte-swap.
483 * \returns `x`, with its bytes in the opposite endian order.
484 *
485 * \threadsafety It is safe to call this function from any thread.
486 *
487 * \since This function is available since SDL 3.2.0.
488 */
489 SDL_FORCE_INLINE Uint64 SDL_Swap64(Uint64 x) { return x_but_byteswapped; }
490
491 /**
492 * Swap a 16-bit value from littleendian to native byte order.
493 *
494 * If this is running on a littleendian system, `x` is returned unchanged.
495 *
496 * This macro never references `x` more than once, avoiding side effects.
497 *
498 * \param x the value to swap, in littleendian byte order.
499 * \returns `x` in native byte order.
500 *
501 * \threadsafety It is safe to call this macro from any thread.
502 *
503 * \since This macro is available since SDL 3.2.0.
504 */
505 #define SDL_Swap16LE(x) SwapOnlyIfNecessary(x)
506
507 /**
508 * Swap a 32-bit value from littleendian to native byte order.
509 *
510 * If this is running on a littleendian system, `x` is returned unchanged.
511 *
512 * This macro never references `x` more than once, avoiding side effects.
513 *
514 * \param x the value to swap, in littleendian byte order.
515 * \returns `x` in native byte order.
516 *
517 * \threadsafety It is safe to call this macro from any thread.
518 *
519 * \since This macro is available since SDL 3.2.0.
520 */
521 #define SDL_Swap32LE(x) SwapOnlyIfNecessary(x)
522
523 /**
524 * Swap a 64-bit value from littleendian to native byte order.
525 *
526 * If this is running on a littleendian system, `x` is returned unchanged.
527 *
528 * This macro never references `x` more than once, avoiding side effects.
529 *
530 * \param x the value to swap, in littleendian byte order.
531 * \returns `x` in native byte order.
532 *
533 * \threadsafety It is safe to call this macro from any thread.
534 *
535 * \since This macro is available since SDL 3.2.0.
536 */
537 #define SDL_Swap64LE(x) SwapOnlyIfNecessary(x)
538
539 /**
540 * Swap a floating point value from littleendian to native byte order.
541 *
542 * If this is running on a littleendian system, `x` is returned unchanged.
543 *
544 * This macro never references `x` more than once, avoiding side effects.
545 *
546 * \param x the value to swap, in littleendian byte order.
547 * \returns `x` in native byte order.
548 *
549 * \threadsafety It is safe to call this macro from any thread.
550 *
551 * \since This macro is available since SDL 3.2.0.
552 */
553 #define SDL_SwapFloatLE(x) SwapOnlyIfNecessary(x)
554
555 /**
556 * Swap a 16-bit value from bigendian to native byte order.
557 *
558 * If this is running on a bigendian system, `x` is returned unchanged.
559 *
560 * This macro never references `x` more than once, avoiding side effects.
561 *
562 * \param x the value to swap, in bigendian byte order.
563 * \returns `x` in native byte order.
564 *
565 * \threadsafety It is safe to call this macro from any thread.
566 *
567 * \since This macro is available since SDL 3.2.0.
568 */
569 #define SDL_Swap16BE(x) SwapOnlyIfNecessary(x)
570
571 /**
572 * Swap a 32-bit value from bigendian to native byte order.
573 *
574 * If this is running on a bigendian system, `x` is returned unchanged.
575 *
576 * This macro never references `x` more than once, avoiding side effects.
577 *
578 * \param x the value to swap, in bigendian byte order.
579 * \returns `x` in native byte order.
580 *
581 * \threadsafety It is safe to call this macro from any thread.
582 *
583 * \since This macro is available since SDL 3.2.0.
584 */
585 #define SDL_Swap32BE(x) SwapOnlyIfNecessary(x)
586
587 /**
588 * Swap a 64-bit value from bigendian to native byte order.
589 *
590 * If this is running on a bigendian system, `x` is returned unchanged.
591 *
592 * This macro never references `x` more than once, avoiding side effects.
593 *
594 * \param x the value to swap, in bigendian byte order.
595 * \returns `x` in native byte order.
596 *
597 * \threadsafety It is safe to call this macro from any thread.
598 *
599 * \since This macro is available since SDL 3.2.0.
600 */
601 #define SDL_Swap64BE(x) SwapOnlyIfNecessary(x)
602
603 /**
604 * Swap a floating point value from bigendian to native byte order.
605 *
606 * If this is running on a bigendian system, `x` is returned unchanged.
607 *
608 * This macro never references `x` more than once, avoiding side effects.
609 *
610 * \param x the value to swap, in bigendian byte order.
611 * \returns `x` in native byte order.
612 *
613 * \threadsafety It is safe to call this macro from any thread.
614 *
615 * \since This macro is available since SDL 3.2.0.
616 */
617 #define SDL_SwapFloatBE(x) SwapOnlyIfNecessary(x)
618
619 #elif SDL_BYTEORDER == SDL_LIL_ENDIAN
620 #define SDL_Swap16LE(x) (x)
621 #define SDL_Swap32LE(x) (x)
622 #define SDL_Swap64LE(x) (x)
623 #define SDL_SwapFloatLE(x) (x)
624 #define SDL_Swap16BE(x) SDL_Swap16(x)
625 #define SDL_Swap32BE(x) SDL_Swap32(x)
626 #define SDL_Swap64BE(x) SDL_Swap64(x)
627 #define SDL_SwapFloatBE(x) SDL_SwapFloat(x)
628 #else
629 #define SDL_Swap16LE(x) SDL_Swap16(x)
630 #define SDL_Swap32LE(x) SDL_Swap32(x)
631 #define SDL_Swap64LE(x) SDL_Swap64(x)
632 #define SDL_SwapFloatLE(x) SDL_SwapFloat(x)
633 #define SDL_Swap16BE(x) (x)
634 #define SDL_Swap32BE(x) (x)
635 #define SDL_Swap64BE(x) (x)
636 #define SDL_SwapFloatBE(x) (x)
637 #endif
638
639 /* Ends C function definitions when using C++ */
640 #ifdef __cplusplus
641 }
642 #endif
643 #include <SDL3/SDL_close_code.h>
644
645 #endif /* SDL_endian_h_ */