2 Simple DirectMedia Layer
3 Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
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.
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:
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.
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.
32 #include "SDL_stdinc.h"
33 #include "SDL_error.h"
35 #include "begin_code.h"
36 /* Set up for C function definitions, even when using C++ */
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 */
50 * This is the read/write operation structure -- very basic.
52 typedef struct SDL_RWops
55 * Return the size of the file in this rwops, or -1 if unknown
57 Sint64 (SDLCALL * size) (struct SDL_RWops * context);
60 * Seek to \c offset relative to \c whence, one of stdio's whence values:
61 * RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END
63 * \return the final offset in the data stream, or -1 on error.
65 Sint64 (SDLCALL * seek) (struct SDL_RWops * context, Sint64 offset,
69 * Read up to \c maxnum objects each of size \c size from the data
70 * stream to the area pointed at by \c ptr.
72 * \return the number of objects read, or 0 at error or end of file.
74 size_t (SDLCALL * read) (struct SDL_RWops * context, void *ptr,
75 size_t size, size_t maxnum);
78 * Write exactly \c num objects each of size \c size from the area
79 * pointed at by \c ptr to data stream.
81 * \return the number of objects written, or 0 at error or end of file.
83 size_t (SDLCALL * write) (struct SDL_RWops * context, const void *ptr,
84 size_t size, size_t num);
87 * Close and free an allocated SDL_RWops structure.
89 * \return 0 if successful or -1 on write error when flushing data.
91 int (SDLCALL * close) (struct SDL_RWops * context);
96 #if defined(__ANDROID__)
100 void *inputStreamRef;
101 void *readableByteChannelRef;
103 void *assetFileDescriptorRef;
109 #elif defined(__WIN32__)
147 * \name RWFrom functions
149 * Functions to create SDL_RWops structures from various data streams.
153 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file,
157 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp,
160 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp,
164 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size);
165 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem,
168 /* @} *//* RWFrom functions */
171 extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void);
172 extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area);
174 #define RW_SEEK_SET 0 /**< Seek from the beginning of data */
175 #define RW_SEEK_CUR 1 /**< Seek relative to current read point */
176 #define RW_SEEK_END 2 /**< Seek relative to the end of data */
179 * \name Read/write macros
181 * Macros to easily read and write from an SDL_RWops structure.
184 #define SDL_RWsize(ctx) (ctx)->size(ctx)
185 #define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence)
186 #define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, RW_SEEK_CUR)
187 #define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n)
188 #define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n)
189 #define SDL_RWclose(ctx) (ctx)->close(ctx)
190 /* @} *//* Read/write macros */
194 * Load all the data from an SDL data stream.
196 * The data is allocated with a zero byte at the end (null terminated)
198 * If \c datasize is not NULL, it is filled with the size of the data read.
200 * If \c freesrc is non-zero, the stream will be closed after being read.
202 * The data should be freed with SDL_free().
204 * \return the data, or NULL if there was an error.
206 extern DECLSPEC void *SDLCALL SDL_LoadFile_RW(SDL_RWops * src, size_t *datasize,
210 * Load an entire file.
214 #define SDL_LoadFile(file, datasize) SDL_LoadFile_RW(SDL_RWFromFile(file, "rb"), datasize, 1)
217 * \name Read endian functions
219 * Read an item of the specified endianness and return in native format.
222 extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src);
223 extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src);
224 extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src);
225 extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src);
226 extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src);
227 extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src);
228 extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src);
229 /* @} *//* Read endian functions */
232 * \name Write endian functions
234 * Write an item of native format to the specified endianness.
237 extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value);
238 extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value);
239 extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value);
240 extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value);
241 extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value);
242 extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value);
243 extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value);
244 /* @} *//* Write endian functions */
246 /* Ends C function definitions when using C++ */
250 #include "close_code.h"
252 #endif /* SDL_rwops_h_ */
254 /* vi: set ts=4 sw=4 expandtab: */