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SDL - Simple DirectMedia Layer
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Copyright (C) 1997-2006 Sam Lantinga
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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/* This file provides a general interface for SDL to read and write
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data sources. It can easily be extended to files, memory, etc.
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#include "SDL_stdinc.h"
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#include "SDL_error.h"
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#include "begin_code.h"
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/* Set up for C function definitions, even when using C++ */
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/* This is the read/write operation structure -- very basic */
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typedef struct SDL_RWops {
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/* Seek to 'offset' relative to whence, one of stdio's whence values:
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SEEK_SET, SEEK_CUR, SEEK_END
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Returns the final offset in the data source.
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int (SDLCALL *seek)(struct SDL_RWops *context, int offset, int whence);
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/* Read up to 'num' objects each of size 'objsize' from the data
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source to the area pointed at by 'ptr'.
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Returns the number of objects read, or -1 if the read failed.
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int (SDLCALL *read)(struct SDL_RWops *context, void *ptr, int size, int maxnum);
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/* Write exactly 'num' objects each of size 'objsize' from the area
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pointed at by 'ptr' to data source.
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Returns 'num', or -1 if the write failed.
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int (SDLCALL *write)(struct SDL_RWops *context, const void *ptr, int size, int num);
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/* Close and free an allocated SDL_FSops structure */
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int (SDLCALL *close)(struct SDL_RWops *context);
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#if defined(__WIN32__) && !defined(__SYMBIAN32__)
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/* Functions to create SDL_RWops structures from various data sources */
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extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFile(const char *file, const char *mode);
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extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFP(FILE *fp, int autoclose);
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extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromMem(void *mem, int size);
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extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromConstMem(const void *mem, int size);
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extern DECLSPEC SDL_RWops * SDLCALL SDL_AllocRW(void);
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extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops *area);
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#define RW_SEEK_SET 0 /* Seek from the beginning of data */
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#define RW_SEEK_CUR 1 /* Seek relative to current read point */
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#define RW_SEEK_END 2 /* Seek relative to the end of data */
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/* Macros to easily read and write from an SDL_RWops structure */
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#define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence)
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#define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, RW_SEEK_CUR)
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#define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n)
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#define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n)
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#define SDL_RWclose(ctx) (ctx)->close(ctx)
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/* Read an item of the specified endianness and return in native format */
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extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops *src);
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extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops *src);
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extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops *src);
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extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops *src);
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extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops *src);
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extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops *src);
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/* Write an item of native format to the specified endianness */
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extern DECLSPEC int SDLCALL SDL_WriteLE16(SDL_RWops *dst, Uint16 value);
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extern DECLSPEC int SDLCALL SDL_WriteBE16(SDL_RWops *dst, Uint16 value);
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extern DECLSPEC int SDLCALL SDL_WriteLE32(SDL_RWops *dst, Uint32 value);
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extern DECLSPEC int SDLCALL SDL_WriteBE32(SDL_RWops *dst, Uint32 value);
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extern DECLSPEC int SDLCALL SDL_WriteLE64(SDL_RWops *dst, Uint64 value);
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extern DECLSPEC int SDLCALL SDL_WriteBE64(SDL_RWops *dst, Uint64 value);
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/* Ends C function definitions when using C++ */
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#include "close_code.h"
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#endif /* _SDL_rwops_h */