1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2022 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 * \file SDL_rwops.h
24 *
25 * This file provides a general interface for SDL to read and write
26 * data streams. It can easily be extended to files, memory, etc.
27 */
28
29#ifndef SDL_rwops_h_
30#define SDL_rwops_h_
31
32#include "SDL_stdinc.h"
33#include "SDL_error.h"
34
35#include "begin_code.h"
36/* Set up for C function definitions, even when using C++ */
37#ifdef __cplusplus
38extern "C" {
39#endif
40
41/* RWops Types */
42#define SDL_RWOPS_UNKNOWN 0U /**< Unknown stream type */
43#define SDL_RWOPS_WINFILE 1U /**< Win32 file */
44#define SDL_RWOPS_STDFILE 2U /**< Stdio file */
45#define SDL_RWOPS_JNIFILE 3U /**< Android asset */
46#define SDL_RWOPS_MEMORY 4U /**< Memory stream */
47#define SDL_RWOPS_MEMORY_RO 5U /**< Read-Only memory stream */
48#if defined(__VITA__)
49#define SDL_RWOPS_VITAFILE 6U /**< Vita file */
50#endif
51
52/**
53 * This is the read/write operation structure -- very basic.
54 */
55typedef struct SDL_RWops
56{
57 /**
58 * Return the size of the file in this rwops, or -1 if unknown
59 */
60 Sint64 (SDLCALL * size) (struct SDL_RWops * context);
61
62 /**
63 * Seek to \c offset relative to \c whence, one of stdio's whence values:
64 * RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END
65 *
66 * \return the final offset in the data stream, or -1 on error.
67 */
68 Sint64 (SDLCALL * seek) (struct SDL_RWops * context, Sint64 offset,
69 int whence);
70
71 /**
72 * Read up to \c maxnum objects each of size \c size from the data
73 * stream to the area pointed at by \c ptr.
74 *
75 * \return the number of objects read, or 0 at error or end of file.
76 */
77 size_t (SDLCALL * read) (struct SDL_RWops * context, void *ptr,
78 size_t size, size_t maxnum);
79
80 /**
81 * Write exactly \c num objects each of size \c size from the area
82 * pointed at by \c ptr to data stream.
83 *
84 * \return the number of objects written, or 0 at error or end of file.
85 */
86 size_t (SDLCALL * write) (struct SDL_RWops * context, const void *ptr,
87 size_t size, size_t num);
88
89 /**
90 * Close and free an allocated SDL_RWops structure.
91 *
92 * \return 0 if successful or -1 on write error when flushing data.
93 */
94 int (SDLCALL * close) (struct SDL_RWops * context);
95
96 Uint32 type;
97 union
98 {
99#if defined(__ANDROID__)
100 struct
101 {
102 void *asset;
103 } androidio;
104#elif defined(__WIN32__)
105 struct
106 {
107 SDL_bool append;
108 void *h;
109 struct
110 {
111 void *data;
112 size_t size;
113 size_t left;
114 } buffer;
115 } windowsio;
116#elif defined(__VITA__)
117 struct
118 {
119 int h;
120 struct
121 {
122 void *data;
123 size_t size;
124 size_t left;
125 } buffer;
126 } vitaio;
127#endif
128
129#ifdef HAVE_STDIO_H
130 struct
131 {
132 SDL_bool autoclose;
133 FILE *fp;
134 } stdio;
135#endif
136 struct
137 {
138 Uint8 *base;
139 Uint8 *here;
140 Uint8 *stop;
141 } mem;
142 struct
143 {
144 void *data1;
145 void *data2;
146 } unknown;
147 } hidden;
148
149} SDL_RWops;
150
151
152/**
153 * \name RWFrom functions
154 *
155 * Functions to create SDL_RWops structures from various data streams.
156 */
157/* @{ */
158
159/**
160 * Use this function to create a new SDL_RWops structure for reading from
161 * and/or writing to a named file.
162 *
163 * The `mode` string is treated roughly the same as in a call to the C
164 * library's fopen(), even if SDL doesn't happen to use fopen() behind the
165 * scenes.
166 *
167 * Available `mode` strings:
168 *
169 * - "r": Open a file for reading. The file must exist.
170 * - "w": Create an empty file for writing. If a file with the same name
171 * already exists its content is erased and the file is treated as a new
172 * empty file.
173 * - "a": Append to a file. Writing operations append data at the end of the
174 * file. The file is created if it does not exist.
175 * - "r+": Open a file for update both reading and writing. The file must
176 * exist.
177 * - "w+": Create an empty file for both reading and writing. If a file with
178 * the same name already exists its content is erased and the file is
179 * treated as a new empty file.
180 * - "a+": Open a file for reading and appending. All writing operations are
181 * performed at the end of the file, protecting the previous content to be
182 * overwritten. You can reposition (fseek, rewind) the internal pointer to
183 * anywhere in the file for reading, but writing operations will move it
184 * back to the end of file. The file is created if it does not exist.
185 *
186 * **NOTE**: In order to open a file as a binary file, a "b" character has to
187 * be included in the `mode` string. This additional "b" character can either
188 * be appended at the end of the string (thus making the following compound
189 * modes: "rb", "wb", "ab", "r+b", "w+b", "a+b") or be inserted between the
190 * letter and the "+" sign for the mixed modes ("rb+", "wb+", "ab+").
191 * Additional characters may follow the sequence, although they should have no
192 * effect. For example, "t" is sometimes appended to make explicit the file is
193 * a text file.
194 *
195 * This function supports Unicode filenames, but they must be encoded in UTF-8
196 * format, regardless of the underlying operating system.
197 *
198 * As a fallback, SDL_RWFromFile() will transparently open a matching filename
199 * in an Android app's `assets`.
200 *
201 * Closing the SDL_RWops will close the file handle SDL is holding internally.
202 *
203 * \param file a UTF-8 string representing the filename to open
204 * \param mode an ASCII string representing the mode to be used for opening
205 * the file.
206 * \returns a pointer to the SDL_RWops structure that is created, or NULL on
207 * failure; call SDL_GetError() for more information.
208 *
209 * \since This function is available since SDL 2.0.0.
210 *
211 * \sa SDL_RWclose
212 * \sa SDL_RWFromConstMem
213 * \sa SDL_RWFromFP
214 * \sa SDL_RWFromMem
215 * \sa SDL_RWread
216 * \sa SDL_RWseek
217 * \sa SDL_RWtell
218 * \sa SDL_RWwrite
219 */
220extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file,
221 const char *mode);
222
223#ifdef HAVE_STDIO_H
224
225extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp, SDL_bool autoclose);
226
227#else
228
229/**
230 * Use this function to create an SDL_RWops structure from a standard I/O file
231 * pointer (stdio.h's `FILE*`).
232 *
233 * This function is not available on Windows, since files opened in an
234 * application on that platform cannot be used by a dynamically linked
235 * library.
236 *
237 * On some platforms, the first parameter is a `void*`, on others, it's a
238 * `FILE*`, depending on what system headers are available to SDL. It is
239 * always intended to be the `FILE*` type from the C runtime's stdio.h.
240 *
241 * \param fp the `FILE*` that feeds the SDL_RWops stream
242 * \param autoclose SDL_TRUE to close the `FILE*` when closing the SDL_RWops,
243 * SDL_FALSE to leave the `FILE*` open when the RWops is
244 * closed
245 * \returns a pointer to the SDL_RWops structure that is created, or NULL on
246 * failure; call SDL_GetError() for more information.
247 *
248 * \since This function is available since SDL 2.0.0.
249 *
250 * \sa SDL_RWclose
251 * \sa SDL_RWFromConstMem
252 * \sa SDL_RWFromFile
253 * \sa SDL_RWFromMem
254 * \sa SDL_RWread
255 * \sa SDL_RWseek
256 * \sa SDL_RWtell
257 * \sa SDL_RWwrite
258 */
259extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp,
260 SDL_bool autoclose);
261#endif
262
263/**
264 * Use this function to prepare a read-write memory buffer for use with
265 * SDL_RWops.
266 *
267 * This function sets up an SDL_RWops struct based on a memory area of a
268 * certain size, for both read and write access.
269 *
270 * This memory buffer is not copied by the RWops; the pointer you provide must
271 * remain valid until you close the stream. Closing the stream will not free
272 * the original buffer.
273 *
274 * If you need to make sure the RWops never writes to the memory buffer, you
275 * should use SDL_RWFromConstMem() with a read-only buffer of memory instead.
276 *
277 * \param mem a pointer to a buffer to feed an SDL_RWops stream
278 * \param size the buffer size, in bytes
279 * \returns a pointer to a new SDL_RWops structure, or NULL if it fails; call
280 * SDL_GetError() for more information.
281 *
282 * \since This function is available since SDL 2.0.0.
283 *
284 * \sa SDL_RWclose
285 * \sa SDL_RWFromConstMem
286 * \sa SDL_RWFromFile
287 * \sa SDL_RWFromFP
288 * \sa SDL_RWFromMem
289 * \sa SDL_RWread
290 * \sa SDL_RWseek
291 * \sa SDL_RWtell
292 * \sa SDL_RWwrite
293 */
294extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size);
295
296/**
297 * Use this function to prepare a read-only memory buffer for use with RWops.
298 *
299 * This function sets up an SDL_RWops struct based on a memory area of a
300 * certain size. It assumes the memory area is not writable.
301 *
302 * Attempting to write to this RWops stream will report an error without
303 * writing to the memory buffer.
304 *
305 * This memory buffer is not copied by the RWops; the pointer you provide must
306 * remain valid until you close the stream. Closing the stream will not free
307 * the original buffer.
308 *
309 * If you need to write to a memory buffer, you should use SDL_RWFromMem()
310 * with a writable buffer of memory instead.
311 *
312 * \param mem a pointer to a read-only buffer to feed an SDL_RWops stream
313 * \param size the buffer size, in bytes
314 * \returns a pointer to a new SDL_RWops structure, or NULL if it fails; call
315 * SDL_GetError() for more information.
316 *
317 * \since This function is available since SDL 2.0.0.
318 *
319 * \sa SDL_RWclose
320 * \sa SDL_RWFromConstMem
321 * \sa SDL_RWFromFile
322 * \sa SDL_RWFromFP
323 * \sa SDL_RWFromMem
324 * \sa SDL_RWread
325 * \sa SDL_RWseek
326 * \sa SDL_RWtell
327 */
328extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem,
329 int size);
330
331/* @} *//* RWFrom functions */
332
333
334/**
335 * Use this function to allocate an empty, unpopulated SDL_RWops structure.
336 *
337 * Applications do not need to use this function unless they are providing
338 * their own SDL_RWops implementation. If you just need a SDL_RWops to
339 * read/write a common data source, you should use the built-in
340 * implementations in SDL, like SDL_RWFromFile() or SDL_RWFromMem(), etc.
341 *
342 * You must free the returned pointer with SDL_FreeRW(). Depending on your
343 * operating system and compiler, there may be a difference between the
344 * malloc() and free() your program uses and the versions SDL calls
345 * internally. Trying to mix the two can cause crashing such as segmentation
346 * faults. Since all SDL_RWops must free themselves when their **close**
347 * method is called, all SDL_RWops must be allocated through this function, so
348 * they can all be freed correctly with SDL_FreeRW().
349 *
350 * \returns a pointer to the allocated memory on success, or NULL on failure;
351 * call SDL_GetError() for more information.
352 *
353 * \since This function is available since SDL 2.0.0.
354 *
355 * \sa SDL_FreeRW
356 */
357extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void);
358
359/**
360 * Use this function to free an SDL_RWops structure allocated by
361 * SDL_AllocRW().
362 *
363 * Applications do not need to use this function unless they are providing
364 * their own SDL_RWops implementation. If you just need a SDL_RWops to
365 * read/write a common data source, you should use the built-in
366 * implementations in SDL, like SDL_RWFromFile() or SDL_RWFromMem(), etc, and
367 * call the **close** method on those SDL_RWops pointers when you are done
368 * with them.
369 *
370 * Only use SDL_FreeRW() on pointers returned by SDL_AllocRW(). The pointer is
371 * invalid as soon as this function returns. Any extra memory allocated during
372 * creation of the SDL_RWops is not freed by SDL_FreeRW(); the programmer must
373 * be responsible for managing that memory in their **close** method.
374 *
375 * \param area the SDL_RWops structure to be freed
376 *
377 * \since This function is available since SDL 2.0.0.
378 *
379 * \sa SDL_AllocRW
380 */
381extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area);
382
383#define RW_SEEK_SET 0 /**< Seek from the beginning of data */
384#define RW_SEEK_CUR 1 /**< Seek relative to current read point */
385#define RW_SEEK_END 2 /**< Seek relative to the end of data */
386
387/**
388 * Use this function to get the size of the data stream in an SDL_RWops.
389 *
390 * Prior to SDL 2.0.10, this function was a macro.
391 *
392 * \param context the SDL_RWops to get the size of the data stream from
393 * \returns the size of the data stream in the SDL_RWops on success, -1 if
394 * unknown or a negative error code on failure; call SDL_GetError()
395 * for more information.
396 *
397 * \since This function is available since SDL 2.0.10.
398 */
399extern DECLSPEC Sint64 SDLCALL SDL_RWsize(SDL_RWops *context);
400
401/**
402 * Seek within an SDL_RWops data stream.
403 *
404 * This function seeks to byte `offset`, relative to `whence`.
405 *
406 * `whence` may be any of the following values:
407 *
408 * - `RW_SEEK_SET`: seek from the beginning of data
409 * - `RW_SEEK_CUR`: seek relative to current read point
410 * - `RW_SEEK_END`: seek relative to the end of data
411 *
412 * If this stream can not seek, it will return -1.
413 *
414 * SDL_RWseek() is actually a wrapper function that calls the SDL_RWops's
415 * `seek` method appropriately, to simplify application development.
416 *
417 * Prior to SDL 2.0.10, this function was a macro.
418 *
419 * \param context a pointer to an SDL_RWops structure
420 * \param offset an offset in bytes, relative to **whence** location; can be
421 * negative
422 * \param whence any of `RW_SEEK_SET`, `RW_SEEK_CUR`, `RW_SEEK_END`
423 * \returns the final offset in the data stream after the seek or -1 on error.
424 *
425 * \since This function is available since SDL 2.0.10.
426 *
427 * \sa SDL_RWclose
428 * \sa SDL_RWFromConstMem
429 * \sa SDL_RWFromFile
430 * \sa SDL_RWFromFP
431 * \sa SDL_RWFromMem
432 * \sa SDL_RWread
433 * \sa SDL_RWtell
434 * \sa SDL_RWwrite
435 */
436extern DECLSPEC Sint64 SDLCALL SDL_RWseek(SDL_RWops *context,
437 Sint64 offset, int whence);
438
439/**
440 * Determine the current read/write offset in an SDL_RWops data stream.
441 *
442 * SDL_RWtell is actually a wrapper function that calls the SDL_RWops's `seek`
443 * method, with an offset of 0 bytes from `RW_SEEK_CUR`, to simplify
444 * application development.
445 *
446 * Prior to SDL 2.0.10, this function was a macro.
447 *
448 * \param context a SDL_RWops data stream object from which to get the current
449 * offset
450 * \returns the current offset in the stream, or -1 if the information can not
451 * be determined.
452 *
453 * \since This function is available since SDL 2.0.10.
454 *
455 * \sa SDL_RWclose
456 * \sa SDL_RWFromConstMem
457 * \sa SDL_RWFromFile
458 * \sa SDL_RWFromFP
459 * \sa SDL_RWFromMem
460 * \sa SDL_RWread
461 * \sa SDL_RWseek
462 * \sa SDL_RWwrite
463 */
464extern DECLSPEC Sint64 SDLCALL SDL_RWtell(SDL_RWops *context);
465
466/**
467 * Read from a data source.
468 *
469 * This function reads up to `maxnum` objects each of size `size` from the
470 * data source to the area pointed at by `ptr`. This function may read less
471 * objects than requested. It will return zero when there has been an error or
472 * the data stream is completely read.
473 *
474 * SDL_RWread() is actually a function wrapper that calls the SDL_RWops's
475 * `read` method appropriately, to simplify application development.
476 *
477 * Prior to SDL 2.0.10, this function was a macro.
478 *
479 * \param context a pointer to an SDL_RWops structure
480 * \param ptr a pointer to a buffer to read data into
481 * \param size the size of each object to read, in bytes
482 * \param maxnum the maximum number of objects to be read
483 * \returns the number of objects read, or 0 at error or end of file; call
484 * SDL_GetError() for more information.
485 *
486 * \since This function is available since SDL 2.0.10.
487 *
488 * \sa SDL_RWclose
489 * \sa SDL_RWFromConstMem
490 * \sa SDL_RWFromFile
491 * \sa SDL_RWFromFP
492 * \sa SDL_RWFromMem
493 * \sa SDL_RWseek
494 * \sa SDL_RWwrite
495 */
496extern DECLSPEC size_t SDLCALL SDL_RWread(SDL_RWops *context,
497 void *ptr, size_t size,
498 size_t maxnum);
499
500/**
501 * Write to an SDL_RWops data stream.
502 *
503 * This function writes exactly `num` objects each of size `size` from the
504 * area pointed at by `ptr` to the stream. If this fails for any reason, it'll
505 * return less than `num` to demonstrate how far the write progressed. On
506 * success, it returns `num`.
507 *
508 * SDL_RWwrite is actually a function wrapper that calls the SDL_RWops's
509 * `write` method appropriately, to simplify application development.
510 *
511 * Prior to SDL 2.0.10, this function was a macro.
512 *
513 * \param context a pointer to an SDL_RWops structure
514 * \param ptr a pointer to a buffer containing data to write
515 * \param size the size of an object to write, in bytes
516 * \param num the number of objects to write
517 * \returns the number of objects written, which will be less than **num** on
518 * error; call SDL_GetError() for more information.
519 *
520 * \since This function is available since SDL 2.0.10.
521 *
522 * \sa SDL_RWclose
523 * \sa SDL_RWFromConstMem
524 * \sa SDL_RWFromFile
525 * \sa SDL_RWFromFP
526 * \sa SDL_RWFromMem
527 * \sa SDL_RWread
528 * \sa SDL_RWseek
529 */
530extern DECLSPEC size_t SDLCALL SDL_RWwrite(SDL_RWops *context,
531 const void *ptr, size_t size,
532 size_t num);
533
534/**
535 * Close and free an allocated SDL_RWops structure.
536 *
537 * SDL_RWclose() closes and cleans up the SDL_RWops stream. It releases any
538 * resources used by the stream and frees the SDL_RWops itself with
539 * SDL_FreeRW(). This returns 0 on success, or -1 if the stream failed to
540 * flush to its output (e.g. to disk).
541 *
542 * Note that if this fails to flush the stream to disk, this function reports
543 * an error, but the SDL_RWops is still invalid once this function returns.
544 *
545 * Prior to SDL 2.0.10, this function was a macro.
546 *
547 * \param context SDL_RWops structure to close
548 * \returns 0 on success or a negative error code on failure; call
549 * SDL_GetError() for more information.
550 *
551 * \since This function is available since SDL 2.0.10.
552 *
553 * \sa SDL_RWFromConstMem
554 * \sa SDL_RWFromFile
555 * \sa SDL_RWFromFP
556 * \sa SDL_RWFromMem
557 * \sa SDL_RWread
558 * \sa SDL_RWseek
559 * \sa SDL_RWwrite
560 */
561extern DECLSPEC int SDLCALL SDL_RWclose(SDL_RWops *context);
562
563/**
564 * Load all the data from an SDL data stream.
565 *
566 * The data is allocated with a zero byte at the end (null terminated) for
567 * convenience. This extra byte is not included in the value reported via
568 * `datasize`.
569 *
570 * The data should be freed with SDL_free().
571 *
572 * \param src the SDL_RWops to read all available data from
573 * \param datasize if not NULL, will store the number of bytes read
574 * \param freesrc if non-zero, calls SDL_RWclose() on `src` before returning
575 * \returns the data, or NULL if there was an error.
576 *
577 * \since This function is available since SDL 2.0.6.
578 */
579extern DECLSPEC void *SDLCALL SDL_LoadFile_RW(SDL_RWops *src,
580 size_t *datasize,
581 int freesrc);
582
583/**
584 * Load all the data from a file path.
585 *
586 * The data is allocated with a zero byte at the end (null terminated) for
587 * convenience. This extra byte is not included in the value reported via
588 * `datasize`.
589 *
590 * The data should be freed with SDL_free().
591 *
592 * Prior to SDL 2.0.10, this function was a macro wrapping around
593 * SDL_LoadFile_RW.
594 *
595 * \param file the path to read all available data from
596 * \param datasize if not NULL, will store the number of bytes read
597 * \returns the data, or NULL if there was an error.
598 *
599 * \since This function is available since SDL 2.0.10.
600 */
601extern DECLSPEC void *SDLCALL SDL_LoadFile(const char *file, size_t *datasize);
602
603/**
604 * \name Read endian functions
605 *
606 * Read an item of the specified endianness and return in native format.
607 */
608/* @{ */
609
610/**
611 * Use this function to read a byte from an SDL_RWops.
612 *
613 * \param src the SDL_RWops to read from
614 * \returns the read byte on success or 0 on failure; call SDL_GetError() for
615 * more information.
616 *
617 * \since This function is available since SDL 2.0.0.
618 *
619 * \sa SDL_WriteU8
620 */
621extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src);
622
623/**
624 * Use this function to read 16 bits of little-endian data from an SDL_RWops
625 * and return in native format.
626 *
627 * SDL byteswaps the data only if necessary, so the data returned will be in
628 * the native byte order.
629 *
630 * \param src the stream from which to read data
631 * \returns 16 bits of data in the native byte order of the platform.
632 *
633 * \since This function is available since SDL 2.0.0.
634 *
635 * \sa SDL_ReadBE16
636 */
637extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src);
638
639/**
640 * Use this function to read 16 bits of big-endian data from an SDL_RWops and
641 * return in native format.
642 *
643 * SDL byteswaps the data only if necessary, so the data returned will be in
644 * the native byte order.
645 *
646 * \param src the stream from which to read data
647 * \returns 16 bits of data in the native byte order of the platform.
648 *
649 * \since This function is available since SDL 2.0.0.
650 *
651 * \sa SDL_ReadLE16
652 */
653extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src);
654
655/**
656 * Use this function to read 32 bits of little-endian data from an SDL_RWops
657 * and return in native format.
658 *
659 * SDL byteswaps the data only if necessary, so the data returned will be in
660 * the native byte order.
661 *
662 * \param src the stream from which to read data
663 * \returns 32 bits of data in the native byte order of the platform.
664 *
665 * \since This function is available since SDL 2.0.0.
666 *
667 * \sa SDL_ReadBE32
668 */
669extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src);
670
671/**
672 * Use this function to read 32 bits of big-endian data from an SDL_RWops and
673 * return in native format.
674 *
675 * SDL byteswaps the data only if necessary, so the data returned will be in
676 * the native byte order.
677 *
678 * \param src the stream from which to read data
679 * \returns 32 bits of data in the native byte order of the platform.
680 *
681 * \since This function is available since SDL 2.0.0.
682 *
683 * \sa SDL_ReadLE32
684 */
685extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src);
686
687/**
688 * Use this function to read 64 bits of little-endian data from an SDL_RWops
689 * and return in native format.
690 *
691 * SDL byteswaps the data only if necessary, so the data returned will be in
692 * the native byte order.
693 *
694 * \param src the stream from which to read data
695 * \returns 64 bits of data in the native byte order of the platform.
696 *
697 * \since This function is available since SDL 2.0.0.
698 *
699 * \sa SDL_ReadBE64
700 */
701extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src);
702
703/**
704 * Use this function to read 64 bits of big-endian data from an SDL_RWops and
705 * return in native format.
706 *
707 * SDL byteswaps the data only if necessary, so the data returned will be in
708 * the native byte order.
709 *
710 * \param src the stream from which to read data
711 * \returns 64 bits of data in the native byte order of the platform.
712 *
713 * \since This function is available since SDL 2.0.0.
714 *
715 * \sa SDL_ReadLE64
716 */
717extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src);
718/* @} *//* Read endian functions */
719
720/**
721 * \name Write endian functions
722 *
723 * Write an item of native format to the specified endianness.
724 */
725/* @{ */
726
727/**
728 * Use this function to write a byte to an SDL_RWops.
729 *
730 * \param dst the SDL_RWops to write to
731 * \param value the byte value to write
732 * \returns 1 on success or 0 on failure; call SDL_GetError() for more
733 * information.
734 *
735 * \since This function is available since SDL 2.0.0.
736 *
737 * \sa SDL_ReadU8
738 */
739extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value);
740
741/**
742 * Use this function to write 16 bits in native format to a SDL_RWops as
743 * little-endian data.
744 *
745 * SDL byteswaps the data only if necessary, so the application always
746 * specifies native format, and the data written will be in little-endian
747 * format.
748 *
749 * \param dst the stream to which data will be written
750 * \param value the data to be written, in native format
751 * \returns 1 on successful write, 0 on error.
752 *
753 * \since This function is available since SDL 2.0.0.
754 *
755 * \sa SDL_WriteBE16
756 */
757extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value);
758
759/**
760 * Use this function to write 16 bits in native format to a SDL_RWops as
761 * big-endian data.
762 *
763 * SDL byteswaps the data only if necessary, so the application always
764 * specifies native format, and the data written will be in big-endian format.
765 *
766 * \param dst the stream to which data will be written
767 * \param value the data to be written, in native format
768 * \returns 1 on successful write, 0 on error.
769 *
770 * \since This function is available since SDL 2.0.0.
771 *
772 * \sa SDL_WriteLE16
773 */
774extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value);
775
776/**
777 * Use this function to write 32 bits in native format to a SDL_RWops as
778 * little-endian data.
779 *
780 * SDL byteswaps the data only if necessary, so the application always
781 * specifies native format, and the data written will be in little-endian
782 * format.
783 *
784 * \param dst the stream to which data will be written
785 * \param value the data to be written, in native format
786 * \returns 1 on successful write, 0 on error.
787 *
788 * \since This function is available since SDL 2.0.0.
789 *
790 * \sa SDL_WriteBE32
791 */
792extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value);
793
794/**
795 * Use this function to write 32 bits in native format to a SDL_RWops as
796 * big-endian data.
797 *
798 * SDL byteswaps the data only if necessary, so the application always
799 * specifies native format, and the data written will be in big-endian format.
800 *
801 * \param dst the stream to which data will be written
802 * \param value the data to be written, in native format
803 * \returns 1 on successful write, 0 on error.
804 *
805 * \since This function is available since SDL 2.0.0.
806 *
807 * \sa SDL_WriteLE32
808 */
809extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value);
810
811/**
812 * Use this function to write 64 bits in native format to a SDL_RWops as
813 * little-endian data.
814 *
815 * SDL byteswaps the data only if necessary, so the application always
816 * specifies native format, and the data written will be in little-endian
817 * format.
818 *
819 * \param dst the stream to which data will be written
820 * \param value the data to be written, in native format
821 * \returns 1 on successful write, 0 on error.
822 *
823 * \since This function is available since SDL 2.0.0.
824 *
825 * \sa SDL_WriteBE64
826 */
827extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value);
828
829/**
830 * Use this function to write 64 bits in native format to a SDL_RWops as
831 * big-endian data.
832 *
833 * SDL byteswaps the data only if necessary, so the application always
834 * specifies native format, and the data written will be in big-endian format.
835 *
836 * \param dst the stream to which data will be written
837 * \param value the data to be written, in native format
838 * \returns 1 on successful write, 0 on error.
839 *
840 * \since This function is available since SDL 2.0.0.
841 *
842 * \sa SDL_WriteLE64
843 */
844extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value);
845/* @} *//* Write endian functions */
846
847/* Ends C function definitions when using C++ */
848#ifdef __cplusplus
849}
850#endif
851#include "close_code.h"
852
853#endif /* SDL_rwops_h_ */
854
855/* vi: set ts=4 sw=4 expandtab: */
856

source code of include/SDL2/SDL_rwops.h