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SDL_rwops.h
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00001 /* 00002 Simple DirectMedia Layer 00003 Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org> 00004 00005 This software is provided 'as-is', without any express or implied 00006 warranty. In no event will the authors be held liable for any damages 00007 arising from the use of this software. 00008 00009 Permission is granted to anyone to use this software for any purpose, 00010 including commercial applications, and to alter it and redistribute it 00011 freely, subject to the following restrictions: 00012 00013 1. The origin of this software must not be misrepresented; you must not 00014 claim that you wrote the original software. If you use this software 00015 in a product, an acknowledgment in the product documentation would be 00016 appreciated but is not required. 00017 2. Altered source versions must be plainly marked as such, and must not be 00018 misrepresented as being the original software. 00019 3. This notice may not be removed or altered from any source distribution. 00020 */ 00021 00022 /** 00023 * \file SDL_rwops.h 00024 * 00025 * This file provides a general interface for SDL to read and write 00026 * data streams. It can easily be extended to files, memory, etc. 00027 */ 00028 00029 #ifndef _SDL_rwops_h 00030 #define _SDL_rwops_h 00031 00032 #include "SDL_stdinc.h" 00033 #include "SDL_error.h" 00034 00035 #include "begin_code.h" 00036 /* Set up for C function definitions, even when using C++ */ 00037 #ifdef __cplusplus 00038 extern "C" { 00039 #endif 00040 00041 /* RWops Types */ 00042 #define SDL_RWOPS_UNKNOWN 0 /* Unknown stream type */ 00043 #define SDL_RWOPS_WINFILE 1 /* Win32 file */ 00044 #define SDL_RWOPS_STDFILE 2 /* Stdio file */ 00045 #define SDL_RWOPS_JNIFILE 3 /* Android asset */ 00046 #define SDL_RWOPS_MEMORY 4 /* Memory stream */ 00047 #define SDL_RWOPS_MEMORY_RO 5 /* Read-Only memory stream */ 00048 00049 /** 00050 * This is the read/write operation structure -- very basic. 00051 */ 00052 typedef struct SDL_RWops 00053 { 00054 /** 00055 * Return the size of the file in this rwops, or -1 if unknown 00056 */ 00057 Sint64 (SDLCALL * size) (struct SDL_RWops * context); 00058 00059 /** 00060 * Seek to \c offset relative to \c whence, one of stdio's whence values: 00061 * RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END 00062 * 00063 * \return the final offset in the data stream, or -1 on error. 00064 */ 00065 Sint64 (SDLCALL * seek) (struct SDL_RWops * context, Sint64 offset, 00066 int whence); 00067 00068 /** 00069 * Read up to \c maxnum objects each of size \c size from the data 00070 * stream to the area pointed at by \c ptr. 00071 * 00072 * \return the number of objects read, or 0 at error or end of file. 00073 */ 00074 size_t (SDLCALL * read) (struct SDL_RWops * context, void *ptr, 00075 size_t size, size_t maxnum); 00076 00077 /** 00078 * Write exactly \c num objects each of size \c size from the area 00079 * pointed at by \c ptr to data stream. 00080 * 00081 * \return the number of objects written, or 0 at error or end of file. 00082 */ 00083 size_t (SDLCALL * write) (struct SDL_RWops * context, const void *ptr, 00084 size_t size, size_t num); 00085 00086 /** 00087 * Close and free an allocated SDL_RWops structure. 00088 * 00089 * \return 0 if successful or -1 on write error when flushing data. 00090 */ 00091 int (SDLCALL * close) (struct SDL_RWops * context); 00092 00093 Uint32 type; 00094 union 00095 { 00096 #if defined(ANDROID) 00097 struct 00098 { 00099 void *fileNameRef; 00100 void *inputStreamRef; 00101 void *readableByteChannelRef; 00102 void *readMethod; 00103 void *assetFileDescriptorRef; 00104 long position; 00105 long size; 00106 long offset; 00107 int fd; 00108 } androidio; 00109 #elif defined(__WIN32__) 00110 struct 00111 { 00112 SDL_bool append; 00113 void *h; 00114 struct 00115 { 00116 void *data; 00117 size_t size; 00118 size_t left; 00119 } buffer; 00120 } windowsio; 00121 #endif 00122 00123 #ifdef HAVE_STDIO_H 00124 struct 00125 { 00126 SDL_bool autoclose; 00127 FILE *fp; 00128 } stdio; 00129 #endif 00130 struct 00131 { 00132 Uint8 *base; 00133 Uint8 *here; 00134 Uint8 *stop; 00135 } mem; 00136 struct 00137 { 00138 void *data1; 00139 void *data2; 00140 } unknown; 00141 } hidden; 00142 00143 } SDL_RWops; 00144 00145 00146 /** 00147 * \name RWFrom functions 00148 * 00149 * Functions to create SDL_RWops structures from various data streams. 00150 */ 00151 /* @{ */ 00152 00153 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file, 00154 const char *mode); 00155 00156 #ifdef HAVE_STDIO_H 00157 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp, 00158 SDL_bool autoclose); 00159 #else 00160 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp, 00161 SDL_bool autoclose); 00162 #endif 00163 00164 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size); 00165 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem, 00166 int size); 00167 00168 /* @} *//* RWFrom functions */ 00169 00170 00171 extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void); 00172 extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area); 00173 00174 #define RW_SEEK_SET 0 /**< Seek from the beginning of data */ 00175 #define RW_SEEK_CUR 1 /**< Seek relative to current read point */ 00176 #define RW_SEEK_END 2 /**< Seek relative to the end of data */ 00177 00178 /** 00179 * \name Read/write macros 00180 * 00181 * Macros to easily read and write from an SDL_RWops structure. 00182 */ 00183 /* @{ */ 00184 #define SDL_RWsize(ctx) (ctx)->size(ctx) 00185 #define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence) 00186 #define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, RW_SEEK_CUR) 00187 #define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n) 00188 #define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n) 00189 #define SDL_RWclose(ctx) (ctx)->close(ctx) 00190 /* @} *//* Read/write macros */ 00191 00192 00193 /** 00194 * \name Read endian functions 00195 * 00196 * Read an item of the specified endianness and return in native format. 00197 */ 00198 /* @{ */ 00199 extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src); 00200 extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src); 00201 extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src); 00202 extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src); 00203 extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src); 00204 extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src); 00205 extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src); 00206 /* @} *//* Read endian functions */ 00207 00208 /** 00209 * \name Write endian functions 00210 * 00211 * Write an item of native format to the specified endianness. 00212 */ 00213 /* @{ */ 00214 extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value); 00215 extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value); 00216 extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value); 00217 extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value); 00218 extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value); 00219 extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value); 00220 extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value); 00221 /* @} *//* Write endian functions */ 00222 00223 00224 /* Ends C function definitions when using C++ */ 00225 #ifdef __cplusplus 00226 } 00227 #endif 00228 #include "close_code.h" 00229 00230 #endif /* _SDL_rwops_h */ 00231 00232 /* vi: set ts=4 sw=4 expandtab: */
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