SDL standard library
Diff: SDL_rwops.h
- Revision:
- 0:dda4f4550403
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SDL_rwops.h Wed Sep 07 18:46:53 2016 +0000 @@ -0,0 +1,232 @@ +/* + Simple DirectMedia Layer + Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org> + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ + +/** + * \file SDL_rwops.h + * + * This file provides a general interface for SDL to read and write + * data streams. It can easily be extended to files, memory, etc. + */ + +#ifndef _SDL_rwops_h +#define _SDL_rwops_h + +#include "SDL_stdinc.h" +#include "SDL_error.h" + +#include "begin_code.h" +/* Set up for C function definitions, even when using C++ */ +#ifdef __cplusplus +extern "C" { +#endif + +/* RWops Types */ +#define SDL_RWOPS_UNKNOWN 0 /* Unknown stream type */ +#define SDL_RWOPS_WINFILE 1 /* Win32 file */ +#define SDL_RWOPS_STDFILE 2 /* Stdio file */ +#define SDL_RWOPS_JNIFILE 3 /* Android asset */ +#define SDL_RWOPS_MEMORY 4 /* Memory stream */ +#define SDL_RWOPS_MEMORY_RO 5 /* Read-Only memory stream */ + +/** + * This is the read/write operation structure -- very basic. + */ +typedef struct SDL_RWops +{ + /** + * Return the size of the file in this rwops, or -1 if unknown + */ + Sint64 (SDLCALL * size) (struct SDL_RWops * context); + + /** + * Seek to \c offset relative to \c whence, one of stdio's whence values: + * RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END + * + * \return the final offset in the data stream, or -1 on error. + */ + Sint64 (SDLCALL * seek) (struct SDL_RWops * context, Sint64 offset, + int whence); + + /** + * Read up to \c maxnum objects each of size \c size from the data + * stream to the area pointed at by \c ptr. + * + * \return the number of objects read, or 0 at error or end of file. + */ + size_t (SDLCALL * read) (struct SDL_RWops * context, void *ptr, + size_t size, size_t maxnum); + + /** + * Write exactly \c num objects each of size \c size from the area + * pointed at by \c ptr to data stream. + * + * \return the number of objects written, or 0 at error or end of file. + */ + size_t (SDLCALL * write) (struct SDL_RWops * context, const void *ptr, + size_t size, size_t num); + + /** + * Close and free an allocated SDL_RWops structure. + * + * \return 0 if successful or -1 on write error when flushing data. + */ + int (SDLCALL * close) (struct SDL_RWops * context); + + Uint32 type; + union + { +#if defined(ANDROID) + struct + { + void *fileNameRef; + void *inputStreamRef; + void *readableByteChannelRef; + void *readMethod; + void *assetFileDescriptorRef; + long position; + long size; + long offset; + int fd; + } androidio; +#elif defined(__WIN32__) + struct + { + SDL_bool append; + void *h; + struct + { + void *data; + size_t size; + size_t left; + } buffer; + } windowsio; +#endif + +#ifdef HAVE_STDIO_H + struct + { + SDL_bool autoclose; + FILE *fp; + } stdio; +#endif + struct + { + Uint8 *base; + Uint8 *here; + Uint8 *stop; + } mem; + struct + { + void *data1; + void *data2; + } unknown; + } hidden; + +} SDL_RWops; + + +/** + * \name RWFrom functions + * + * Functions to create SDL_RWops structures from various data streams. + */ +/* @{ */ + +extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file, + const char *mode); + +#ifdef HAVE_STDIO_H +extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp, + SDL_bool autoclose); +#else +extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp, + SDL_bool autoclose); +#endif + +extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size); +extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem, + int size); + +/* @} *//* RWFrom functions */ + + +extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void); +extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area); + +#define RW_SEEK_SET 0 /**< Seek from the beginning of data */ +#define RW_SEEK_CUR 1 /**< Seek relative to current read point */ +#define RW_SEEK_END 2 /**< Seek relative to the end of data */ + +/** + * \name Read/write macros + * + * Macros to easily read and write from an SDL_RWops structure. + */ +/* @{ */ +#define SDL_RWsize(ctx) (ctx)->size(ctx) +#define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence) +#define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, RW_SEEK_CUR) +#define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n) +#define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n) +#define SDL_RWclose(ctx) (ctx)->close(ctx) +/* @} *//* Read/write macros */ + + +/** + * \name Read endian functions + * + * Read an item of the specified endianness and return in native format. + */ +/* @{ */ +extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src); +extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src); +extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src); +extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src); +extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src); +extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src); +extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src); +/* @} *//* Read endian functions */ + +/** + * \name Write endian functions + * + * Write an item of native format to the specified endianness. + */ +/* @{ */ +extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value); +extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value); +extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value); +extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value); +extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value); +extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value); +extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value); +/* @} *//* Write endian functions */ + + +/* Ends C function definitions when using C++ */ +#ifdef __cplusplus +} +#endif +#include "close_code.h" + +#endif /* _SDL_rwops_h */ + +/* vi: set ts=4 sw=4 expandtab: */