SDL  2.0
SDL_rwops.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2019 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  */
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  */
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 
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  {
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  {
127  FILE *fp;
128  } stdio;
129 #endif
130  struct
131  {
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 
153 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFile(const char *file,
154  const char *mode);
155 
156 #ifdef HAVE_STDIO_H
157 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(FILE * fp,
159 #else
160 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromFP(void * fp,
162 #endif
163 
164 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromMem(void *mem, int size);
165 extern DECLSPEC SDL_RWops *SDLCALL SDL_RWFromConstMem(const void *mem,
166  int size);
167 
168 /* @} *//* RWFrom functions */
169 
170 
171 extern DECLSPEC SDL_RWops *SDLCALL SDL_AllocRW(void);
172 extern 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  * Return the size of the file in this rwops, or -1 if unknown
180  */
182 
183 /**
184  * Seek to \c offset relative to \c whence, one of stdio's whence values:
185  * RW_SEEK_SET, RW_SEEK_CUR, RW_SEEK_END
186  *
187  * \return the final offset in the data stream, or -1 on error.
188  */
190  Sint64 offset, int whence);
191 
192 /**
193  * Return the current offset in the data stream, or -1 on error.
194  */
196 
197 /**
198  * Read up to \c maxnum objects each of size \c size from the data
199  * stream to the area pointed at by \c ptr.
200  *
201  * \return the number of objects read, or 0 at error or end of file.
202  */
204  void *ptr, size_t size, size_t maxnum);
205 
206 /**
207  * Write exactly \c num objects each of size \c size from the area
208  * pointed at by \c ptr to data stream.
209  *
210  * \return the number of objects written, or 0 at error or end of file.
211  */
213  const void *ptr, size_t size, size_t num);
214 
215 /**
216  * Close and free an allocated SDL_RWops structure.
217  *
218  * \return 0 if successful or -1 on write error when flushing data.
219  */
221 
222 /**
223  * Load all the data from an SDL data stream.
224  *
225  * The data is allocated with a zero byte at the end (null terminated)
226  *
227  * If \c datasize is not NULL, it is filled with the size of the data read.
228  *
229  * If \c freesrc is non-zero, the stream will be closed after being read.
230  *
231  * The data should be freed with SDL_free().
232  *
233  * \return the data, or NULL if there was an error.
234  */
235 extern DECLSPEC void *SDLCALL SDL_LoadFile_RW(SDL_RWops * src, size_t *datasize,
236  int freesrc);
237 
238 /**
239  * Load an entire file.
240  *
241  * The data is allocated with a zero byte at the end (null terminated)
242  *
243  * If \c datasize is not NULL, it is filled with the size of the data read.
244  *
245  * If \c freesrc is non-zero, the stream will be closed after being read.
246  *
247  * The data should be freed with SDL_free().
248  *
249  * \return the data, or NULL if there was an error.
250  */
251 extern DECLSPEC void *SDLCALL SDL_LoadFile(const char *file, size_t *datasize);
252 
253 /**
254  * \name Read endian functions
255  *
256  * Read an item of the specified endianness and return in native format.
257  */
258 /* @{ */
266 /* @} *//* Read endian functions */
267 
268 /**
269  * \name Write endian functions
270  *
271  * Write an item of native format to the specified endianness.
272  */
273 /* @{ */
281 /* @} *//* Write endian functions */
282 
283 /* Ends C function definitions when using C++ */
284 #ifdef __cplusplus
285 }
286 #endif
287 #include "close_code.h"
288 
289 #endif /* SDL_rwops_h_ */
290 
291 /* vi: set ts=4 sw=4 expandtab: */
DECLSPEC
#define DECLSPEC
Definition: SDL_internal.h:48
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_RWops::data
void * data
Definition: SDL_rwops.h:116
SDL_RWops::size
Sint64(* size)(struct SDL_RWops *context)
Definition: SDL_rwops.h:57
SDL_RWops::here
Uint8 * here
Definition: SDL_rwops.h:133
SDL_RWops::append
SDL_bool append
Definition: SDL_rwops.h:112
offset
GLintptr offset
Definition: SDL_opengl_glext.h:538
SDL_ReadBE32
Uint32 SDL_ReadBE32(SDL_RWops *src)
Definition: SDL_rwops.c:836
Sint64
int64_t Sint64
Definition: SDL_stdinc.h:210
SDL_RWops::mem
struct SDL_RWops::@9::@12 mem
SDL_RWops::stop
Uint8 * stop
Definition: SDL_rwops.h:134
mode
GLenum mode
Definition: SDL_opengl_glext.h:1122
SDL_error.h
SDL_RWops::read
size_t(* read)(struct SDL_RWops *context, void *ptr, size_t size, size_t maxnum)
Definition: SDL_rwops.h:74
SDLCALL
#define SDLCALL
Definition: SDL_internal.h:49
SDL_RWops::windowsio
struct SDL_RWops::@9::@10 windowsio
SDL_RWops::h
void * h
Definition: SDL_rwops.h:113
SDL_WriteLE32
size_t SDL_WriteLE32(SDL_RWops *dst, Uint32 value)
Definition: SDL_rwops.c:883
SDL_RWops::hidden
union SDL_RWops::@9 hidden
num
GLuint num
Definition: SDL_opengl_glext.h:4956
SDL_RWFromFP
SDL_RWops * SDL_RWFromFP(FILE *fp, SDL_bool autoclose)
SDL_WriteBE32
size_t SDL_WriteBE32(SDL_RWops *dst, Uint32 value)
Definition: SDL_rwops.c:890
SDL_RWops::write
size_t(* write)(struct SDL_RWops *context, const void *ptr, size_t size, size_t num)
Definition: SDL_rwops.h:83
SDL_FreeRW
void SDL_FreeRW(SDL_RWops *area)
Definition: SDL_rwops.c:697
SDL_ReadBE16
Uint16 SDL_ReadBE16(SDL_RWops *src)
Definition: SDL_rwops.c:818
SDL_RWops::base
Uint8 * base
Definition: SDL_rwops.h:132
SDL_RWops::left
size_t left
Definition: SDL_rwops.h:118
SDL_RWFromConstMem
SDL_RWops * SDL_RWFromConstMem(const void *mem, int size)
Definition: SDL_rwops.c:655
close_code.h
SDL_RWops::buffer
struct SDL_RWops::@9::@10::@14 buffer
begin_code.h
SDL_RWops::seek
Sint64(* seek)(struct SDL_RWops *context, Sint64 offset, int whence)
Definition: SDL_rwops.h:65
dst
GLenum GLenum dst
Definition: SDL_opengl_glext.h:1737
SDL_WriteU8
size_t SDL_WriteU8(SDL_RWops *dst, Uint8 value)
Definition: SDL_rwops.c:863
SDL_LoadFile_RW
void * SDL_LoadFile_RW(SDL_RWops *src, size_t *datasize, int freesrc)
Definition: SDL_rwops.c:704
context
static screen_context_t context
Definition: video.c:25
SDL_AllocRW
SDL_RWops * SDL_AllocRW(void)
Definition: SDL_dynapi_procs.h:385
SDL_RWwrite
size_t SDL_RWwrite(SDL_RWops *context, const void *ptr, size_t size, size_t num)
Definition: SDL_rwops.c:786
SDL_RWops::close
int(* close)(struct SDL_RWops *context)
Definition: SDL_rwops.h:91
SDL_RWops::type
Uint32 type
Definition: SDL_rwops.h:93
SDL_RWclose
int SDL_RWclose(SDL_RWops *context)
Definition: SDL_rwops.c:792
SDL_ReadLE16
Uint16 SDL_ReadLE16(SDL_RWops *src)
Definition: SDL_rwops.c:809
SDL_RWsize
Sint64 SDL_RWsize(SDL_RWops *context)
Definition: SDL_rwops.c:762
SDL_WriteBE16
size_t SDL_WriteBE16(SDL_RWops *dst, Uint16 value)
Definition: SDL_rwops.c:876
Uint16
uint16_t Uint16
Definition: SDL_stdinc.h:191
SDL_RWtell
Sint64 SDL_RWtell(SDL_RWops *context)
Definition: SDL_rwops.c:774
SDL_ReadLE32
Uint32 SDL_ReadLE32(SDL_RWops *src)
Definition: SDL_rwops.c:827
SDL_RWops::autoclose
SDL_bool autoclose
Definition: SDL_rwops.h:126
SDL_RWops::unknown
struct SDL_RWops::@9::@13 unknown
SDL_ReadU8
Uint8 SDL_ReadU8(SDL_RWops *src)
Definition: SDL_rwops.c:800
size
GLsizeiptr size
Definition: SDL_opengl_glext.h:537
src
GLenum src
Definition: SDL_opengl_glext.h:1737
SDL_WriteBE64
size_t SDL_WriteBE64(SDL_RWops *dst, Uint64 value)
Definition: SDL_rwops.c:904
value
GLsizei const GLfloat * value
Definition: SDL_opengl_glext.h:698
SDL_RWops::stdio
struct SDL_RWops::@9::@11 stdio
Uint64
uint64_t Uint64
Definition: SDL_stdinc.h:216
SDL_WriteLE64
size_t SDL_WriteLE64(SDL_RWops *dst, Uint64 value)
Definition: SDL_rwops.c:897
SDL_RWops::fp
FILE * fp
Definition: SDL_rwops.h:127
SDL_stdinc.h
SDL_RWseek
Sint64 SDL_RWseek(SDL_RWops *context, Sint64 offset, int whence)
Definition: SDL_rwops.c:768
SDL_RWFromFile
SDL_RWops * SDL_RWFromFile(const char *file, const char *mode)
Definition: SDL_rwops.c:511
size_t
unsigned int size_t
Definition: SDL_config_windows.h:68
SDL_ReadBE64
Uint64 SDL_ReadBE64(SDL_RWops *src)
Definition: SDL_rwops.c:854
SDL_ReadLE64
Uint64 SDL_ReadLE64(SDL_RWops *src)
Definition: SDL_rwops.c:845
SDL_WriteLE16
size_t SDL_WriteLE16(SDL_RWops *dst, Uint16 value)
Definition: SDL_rwops.c:869
SDL_RWread
size_t SDL_RWread(SDL_RWops *context, void *ptr, size_t size, size_t maxnum)
Definition: SDL_rwops.c:780
fd
GLuint64 GLenum GLint fd
Definition: gl2ext.h:1508
SDL_RWops
Definition: SDL_rwops.h:52
SDL_RWops::data1
void * data1
Definition: SDL_rwops.h:138
SDL_RWops::size
size_t size
Definition: SDL_rwops.h:117
SDL_RWFromMem
SDL_RWops * SDL_RWFromMem(void *mem, int size)
Definition: SDL_rwops.c:627
SDL_LoadFile
void * SDL_LoadFile(const char *file, size_t *datasize)
Definition: SDL_rwops.c:756
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:161
SDL_RWops::data2
void * data2
Definition: SDL_rwops.h:139
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179