SDL_rwops.h (7242B)
1/* 2 Simple DirectMedia Layer 3 Copyright (C) 1997-2014 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 0 /* Unknown stream type */ 43#define SDL_RWOPS_WINFILE 1 /* Win32 file */ 44#define SDL_RWOPS_STDFILE 2 /* Stdio file */ 45#define SDL_RWOPS_JNIFILE 3 /* Android asset */ 46#define SDL_RWOPS_MEMORY 4 /* Memory stream */ 47#define SDL_RWOPS_MEMORY_RO 5 /* Read-Only memory stream */ 48 49/** 50 * This is the read/write operation structure -- very basic. 51 */ 52typedef struct SDL_RWops 53{ 54 /** 55 * Return the size of the file in this rwops, or -1 if unknown 56 */ 57 Sint64 (SDLCALL * size) (struct SDL_RWops * context); 58 59 /** 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 62 * 63 * \return the final offset in the data stream, or -1 on error. 64 */ 65 Sint64 (SDLCALL * seek) (struct SDL_RWops * context, Sint64 offset, 66 int whence); 67 68 /** 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. 71 * 72 * \return the number of objects read, or 0 at error or end of file. 73 */ 74 size_t (SDLCALL * read) (struct SDL_RWops * context, void *ptr, 75 size_t size, size_t maxnum); 76 77 /** 78 * Write exactly \c num objects each of size \c size from the area 79 * pointed at by \c ptr to data stream. 80 * 81 * \return the number of objects written, or 0 at error or end of file. 82 */ 83 size_t (SDLCALL * write) (struct SDL_RWops * context, const void *ptr, 84 size_t size, size_t num); 85 86 /** 87 * Close and free an allocated SDL_RWops structure. 88 * 89 * \return 0 if successful or -1 on write error when flushing data. 90 */ 91 int (SDLCALL * close) (struct SDL_RWops * context); 92 93 Uint32 type; 94 union 95 { 96#if defined(__ANDROID__) 97 struct 98 { 99 void *fileNameRef; 100 void *inputStreamRef; 101 void *readableByteChannelRef; 102 void *readMethod; 103 void *assetFileDescriptorRef; 104 long position; 105 long size; 106 long offset; 107 int fd; 108 } androidio; 109#elif defined(__WIN32__) 110 struct 111 { 112 SDL_bool append; 113 void *h; 114 struct 115 { 116 void *data; 117 size_t size; 118 size_t left; 119 } buffer; 120 } windowsio; 121#endif 122 123#ifdef HAVE_STDIO_H 124 struct 125 { 126 SDL_bool autoclose; 127 FILE *fp; 128 } stdio; 129#endif 130 struct 131 { 132 Uint8 *base; 133 Uint8 *here; 134 Uint8 *stop; 135 } mem; 136 struct 137 { 138 void *data1; 139 void *data2; 140 } unknown; 141 } hidden; 142 143} SDL_RWops; 144 145 146/** 147 * \name RWFrom functions 148 * 149 * Functions to create SDL_RWops structures from various data streams. 150 */ 151/* @{ */ 152 153extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file, 154 const char *mode); 155 156#ifdef HAVE_STDIO_H 157extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp, 158 SDL_bool autoclose); 159#else 160extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp, 161 SDL_bool autoclose); 162#endif 163 164extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size); 165extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem, 166 int size); 167 168/* @} *//* RWFrom functions */ 169 170 171extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void); 172extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area); 173 174#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 */ 177 178/** 179 * \name Read/write macros 180 * 181 * Macros to easily read and write from an SDL_RWops structure. 182 */ 183/* @{ */ 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 */ 191 192 193/** 194 * \name Read endian functions 195 * 196 * Read an item of the specified endianness and return in native format. 197 */ 198/* @{ */ 199extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src); 200extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src); 201extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src); 202extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src); 203extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src); 204extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src); 205extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src); 206/* @} *//* Read endian functions */ 207 208/** 209 * \name Write endian functions 210 * 211 * Write an item of native format to the specified endianness. 212 */ 213/* @{ */ 214extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value); 215extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value); 216extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value); 217extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value); 218extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value); 219extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value); 220extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value); 221/* @} *//* Write endian functions */ 222 223/* Ends C function definitions when using C++ */ 224#ifdef __cplusplus 225} 226#endif 227#include "close_code.h" 228 229#endif /* _SDL_rwops_h */ 230 231/* vi: set ts=4 sw=4 expandtab: */