SDL  2.0
SDL_rwops.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 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  * \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  * Load all the data from an SDL data stream.
195  *
196  * The data is allocated with a zero byte at the end (null terminated)
197  *
198  * If \c datasize is not NULL, it is filled with the size of the data read.
199  *
200  * If \c freesrc is non-zero, the stream will be closed after being read.
201  *
202  * The data should be freed with SDL_free().
203  *
204  * \return the data, or NULL if there was an error.
205  */
206 extern DECLSPEC void *SDLCALL SDL_LoadFile_RW(SDL_RWops * src, size_t *datasize,
207  int freesrc);
208 
209 /**
210  * Load an entire file.
211  *
212  * Convenience macro.
213  */
214 #define SDL_LoadFile(file, datasize) SDL_LoadFile_RW(SDL_RWFromFile(file, "rb"), datasize, 1)
215 
216 /**
217  * \name Read endian functions
218  *
219  * Read an item of the specified endianness and return in native format.
220  */
221 /* @{ */
229 /* @} *//* Read endian functions */
230 
231 /**
232  * \name Write endian functions
233  *
234  * Write an item of native format to the specified endianness.
235  */
236 /* @{ */
244 /* @} *//* Write endian functions */
245 
246 /* Ends C function definitions when using C++ */
247 #ifdef __cplusplus
248 }
249 #endif
250 #include "close_code.h"
251 
252 #endif /* SDL_rwops_h_ */
253 
254 /* vi: set ts=4 sw=4 expandtab: */
Uint32 SDL_ReadBE32(SDL_RWops *src)
Definition: SDL_rwops.c:793
FILE * fp
Definition: SDL_rwops.h:127
GLuint num
void * data
Definition: SDL_rwops.h:116
SDL_bool append
Definition: SDL_rwops.h:112
GLenum GLenum dst
size_t left
Definition: SDL_rwops.h:118
size_t size
Definition: SDL_rwops.h:117
SDL_RWops * SDL_RWFromFP(FILE *fp, SDL_bool autoclose)
static screen_context_t context
Definition: video.c:25
size_t(* write)(struct SDL_RWops *context, const void *ptr, size_t size, size_t num)
Definition: SDL_rwops.h:83
Uint16 SDL_ReadBE16(SDL_RWops *src)
Definition: SDL_rwops.c:775
GLintptr offset
SDL_RWops * SDL_RWFromConstMem(const void *mem, int size)
Definition: SDL_rwops.c:654
Uint8 * stop
Definition: SDL_rwops.h:134
size_t SDL_WriteLE32(SDL_RWops *dst, Uint32 value)
Definition: SDL_rwops.c:840
uint32_t Uint32
Definition: SDL_stdinc.h:181
void * h
Definition: SDL_rwops.h:113
void * data2
Definition: SDL_rwops.h:139
GLenum src
void SDL_FreeRW(SDL_RWops *area)
Definition: SDL_rwops.c:696
uint64_t Uint64
Definition: SDL_stdinc.h:194
size_t SDL_WriteBE32(SDL_RWops *dst, Uint32 value)
Definition: SDL_rwops.c:847
SDL_bool autoclose
Definition: SDL_rwops.h:126
Uint32 type
Definition: SDL_rwops.h:93
struct SDL_RWops::@10::@11 windowsio
struct SDL_RWops::@10::@13 mem
size_t SDL_WriteU8(SDL_RWops *dst, Uint8 value)
Definition: SDL_rwops.c:820
struct SDL_RWops::@10::@12 stdio
Sint64(* seek)(struct SDL_RWops *context, Sint64 offset, int whence)
Definition: SDL_rwops.h:65
struct SDL_RWops::@10::@11::@15 buffer
unsigned int size_t
#define DECLSPEC
Definition: SDL_internal.h:44
size_t SDL_WriteBE16(SDL_RWops *dst, Uint16 value)
Definition: SDL_rwops.c:833
void * SDL_LoadFile_RW(SDL_RWops *src, size_t *datasize, int freesrc)
Definition: SDL_rwops.c:703
uint8_t Uint8
Definition: SDL_stdinc.h:157
Uint8 * base
Definition: SDL_rwops.h:132
SDL_RWops * SDL_AllocRW(void)
Definition: SDL_rwops.c:682
int(* close)(struct SDL_RWops *context)
Definition: SDL_rwops.h:91
Uint16 SDL_ReadLE16(SDL_RWops *src)
Definition: SDL_rwops.c:766
GLenum mode
GLsizei const GLfloat * value
Uint32 SDL_ReadLE32(SDL_RWops *src)
Definition: SDL_rwops.c:784
GLsizeiptr size
size_t SDL_WriteBE64(SDL_RWops *dst, Uint64 value)
Definition: SDL_rwops.c:861
Sint64(* size)(struct SDL_RWops *context)
Definition: SDL_rwops.h:57
SDL_bool
Definition: SDL_stdinc.h:139
Uint8 SDL_ReadU8(SDL_RWops *src)
Definition: SDL_rwops.c:757
union SDL_RWops::@10 hidden
size_t(* read)(struct SDL_RWops *context, void *ptr, size_t size, size_t maxnum)
Definition: SDL_rwops.h:74
uint16_t Uint16
Definition: SDL_stdinc.h:169
Uint64 SDL_ReadBE64(SDL_RWops *src)
Definition: SDL_rwops.c:811
struct SDL_RWops::@10::@14 unknown
size_t SDL_WriteLE64(SDL_RWops *dst, Uint64 value)
Definition: SDL_rwops.c:854
size_t SDL_WriteLE16(SDL_RWops *dst, Uint16 value)
Definition: SDL_rwops.c:826
SDL_RWops * SDL_RWFromFile(const char *file, const char *mode)
Definition: SDL_rwops.c:511
int64_t Sint64
Definition: SDL_stdinc.h:188
void * data1
Definition: SDL_rwops.h:138
Uint8 * here
Definition: SDL_rwops.h:133
SDL_RWops * SDL_RWFromMem(void *mem, int size)
Definition: SDL_rwops.c:626
#define SDLCALL
Definition: SDL_internal.h:45
Uint64 SDL_ReadLE64(SDL_RWops *src)
Definition: SDL_rwops.c:802
GLuint64 GLenum GLint fd
Definition: gl2ext.h:1508