include/SDL_rwops.h
author Manuel Alfayate Corchete
Sat, 23 Jan 2021 22:47:06 +0100
changeset 14788 592afde63bb7
parent 14640 b2b3343a310d
permissions -rw-r--r--
[KMS/DRM] Bugfix for #5489: Non-FULLSCREEN windows incorrecty use videomode changing to look fullscreen.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2021 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
    38 extern "C" {
    39 #endif
    40 
    41 /* RWops Types */
    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 */
    48 
    49 /**
    50  * This is the read/write operation structure -- very basic.
    51  */
    52 typedef 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 *asset;
   100         } androidio;
   101 #elif defined(__WIN32__)
   102         struct
   103         {
   104             SDL_bool append;
   105             void *h;
   106             struct
   107             {
   108                 void *data;
   109                 size_t size;
   110                 size_t left;
   111             } buffer;
   112         } windowsio;
   113 #endif
   114 
   115 #ifdef HAVE_STDIO_H
   116         struct
   117         {
   118             SDL_bool autoclose;
   119             FILE *fp;
   120         } stdio;
   121 #endif
   122         struct
   123         {
   124             Uint8 *base;
   125             Uint8 *here;
   126             Uint8 *stop;
   127         } mem;
   128         struct
   129         {
   130             void *data1;
   131             void *data2;
   132         } unknown;
   133     } hidden;
   134 
   135 } SDL_RWops;
   136 
   137 
   138 /**
   139  *  \name RWFrom functions
   140  *
   141  *  Functions to create SDL_RWops structures from various data streams.
   142  */
   143 /* @{ */
   144 
   145 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file,
   146                                                   const char *mode);
   147 
   148 #ifdef HAVE_STDIO_H
   149 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp,
   150                                                 SDL_bool autoclose);
   151 #else
   152 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp,
   153                                                 SDL_bool autoclose);
   154 #endif
   155 
   156 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size);
   157 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem,
   158                                                       int size);
   159 
   160 /* @} *//* RWFrom functions */
   161 
   162 
   163 extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void);
   164 extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops * area);
   165 
   166 #define RW_SEEK_SET 0       /**< Seek from the beginning of data */
   167 #define RW_SEEK_CUR 1       /**< Seek relative to current read point */
   168 #define RW_SEEK_END 2       /**< Seek relative to the end of data */
   169 
   170 /**
   171  *  Return the size of the file in this rwops, or -1 if unknown
   172  */
   173 extern DECLSPEC Sint64 SDLCALL SDL_RWsize(SDL_RWops *context);
   174 
   175 /**
   176  *  Seek to \c offset relative to \c whence, one of stdio's whence values:
   177  *  RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END
   178  *
   179  *  \return the final offset in the data stream, or -1 on error.
   180  */
   181 extern DECLSPEC Sint64 SDLCALL SDL_RWseek(SDL_RWops *context,
   182                                           Sint64 offset, int whence);
   183 
   184 /**
   185  *  Return the current offset in the data stream, or -1 on error.
   186  */
   187 extern DECLSPEC Sint64 SDLCALL SDL_RWtell(SDL_RWops *context);
   188 
   189 /**
   190  *  Read up to \c maxnum objects each of size \c size from the data
   191  *  stream to the area pointed at by \c ptr.
   192  *
   193  *  \return the number of objects read, or 0 at error or end of file.
   194  */
   195 extern DECLSPEC size_t SDLCALL SDL_RWread(SDL_RWops *context,
   196                                           void *ptr, size_t size, size_t maxnum);
   197 
   198 /**
   199  *  Write exactly \c num objects each of size \c size from the area
   200  *  pointed at by \c ptr to data stream.
   201  *
   202  *  \return the number of objects written, or 0 at error or end of file.
   203  */
   204 extern DECLSPEC size_t SDLCALL SDL_RWwrite(SDL_RWops *context,
   205                                            const void *ptr, size_t size, size_t num);
   206 
   207 /**
   208  *  Close and free an allocated SDL_RWops structure.
   209  *
   210  *  \return 0 if successful or -1 on write error when flushing data.
   211  */
   212 extern DECLSPEC int SDLCALL SDL_RWclose(SDL_RWops *context);
   213 
   214 /**
   215  *  Load all the data from an SDL data stream.
   216  *
   217  *  The data is allocated with a zero byte at the end (null terminated)
   218  *
   219  *  If \c datasize is not NULL, it is filled with the size of the data read.
   220  *
   221  *  If \c freesrc is non-zero, the stream will be closed after being read.
   222  *
   223  *  The data should be freed with SDL_free().
   224  *
   225  *  \return the data, or NULL if there was an error.
   226  */
   227 extern DECLSPEC void *SDLCALL SDL_LoadFile_RW(SDL_RWops * src, size_t *datasize,
   228                                                     int freesrc);
   229 
   230 /**
   231  *  Load an entire file.
   232  *
   233  *  The data is allocated with a zero byte at the end (null terminated)
   234  *
   235  *  If \c datasize is not NULL, it is filled with the size of the data read.
   236  *
   237  *  If \c freesrc is non-zero, the stream will be closed after being read.
   238  *
   239  *  The data should be freed with SDL_free().
   240  *
   241  *  \return the data, or NULL if there was an error.
   242  */
   243 extern DECLSPEC void *SDLCALL SDL_LoadFile(const char *file, size_t *datasize);
   244 
   245 /**
   246  *  \name Read endian functions
   247  *
   248  *  Read an item of the specified endianness and return in native format.
   249  */
   250 /* @{ */
   251 extern DECLSPEC Uint8 SDLCALL SDL_ReadU8(SDL_RWops * src);
   252 extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops * src);
   253 extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops * src);
   254 extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops * src);
   255 extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops * src);
   256 extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops * src);
   257 extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops * src);
   258 /* @} *//* Read endian functions */
   259 
   260 /**
   261  *  \name Write endian functions
   262  *
   263  *  Write an item of native format to the specified endianness.
   264  */
   265 /* @{ */
   266 extern DECLSPEC size_t SDLCALL SDL_WriteU8(SDL_RWops * dst, Uint8 value);
   267 extern DECLSPEC size_t SDLCALL SDL_WriteLE16(SDL_RWops * dst, Uint16 value);
   268 extern DECLSPEC size_t SDLCALL SDL_WriteBE16(SDL_RWops * dst, Uint16 value);
   269 extern DECLSPEC size_t SDLCALL SDL_WriteLE32(SDL_RWops * dst, Uint32 value);
   270 extern DECLSPEC size_t SDLCALL SDL_WriteBE32(SDL_RWops * dst, Uint32 value);
   271 extern DECLSPEC size_t SDLCALL SDL_WriteLE64(SDL_RWops * dst, Uint64 value);
   272 extern DECLSPEC size_t SDLCALL SDL_WriteBE64(SDL_RWops * dst, Uint64 value);
   273 /* @} *//* Write endian functions */
   274 
   275 /* Ends C function definitions when using C++ */
   276 #ifdef __cplusplus
   277 }
   278 #endif
   279 #include "close_code.h"
   280 
   281 #endif /* SDL_rwops_h_ */
   282 
   283 /* vi: set ts=4 sw=4 expandtab: */