[sdl_omap.git] / include / SDL_rwops.h

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/

/** @file SDL_rwops.h
 *  This file provides a general interface for SDL to read and write
 *  data sources.  It can easily be extended to files, memory, etc.
 */

#ifndef _SDL_rwops_h
#define _SDL_rwops_h

#include "SDL_stdinc.h"
#include "SDL_error.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/** This is the read/write operation structure -- very basic */

typedef struct SDL_RWops {
	/** Seek to 'offset' relative to whence, one of stdio's whence values:
	 *	SEEK_SET, SEEK_CUR, SEEK_END
	 *  Returns the final offset in the data source.
	 */
	int (SDLCALL *seek)(struct SDL_RWops *context, int offset, int whence);

	/** Read up to 'maxnum' objects each of size 'size' from the data
	 *  source to the area pointed at by 'ptr'.
	 *  Returns the number of objects read, or -1 if the read failed.
	 */
	int (SDLCALL *read)(struct SDL_RWops *context, void *ptr, int size, int maxnum);

	/** Write exactly 'num' objects each of size 'objsize' from the area
	 *  pointed at by 'ptr' to data source.
	 *  Returns 'num', or -1 if the write failed.
	 */
	int (SDLCALL *write)(struct SDL_RWops *context, const void *ptr, int size, int num);

	/** Close and free an allocated SDL_FSops structure */
	int (SDLCALL *close)(struct SDL_RWops *context);

	Uint32 type;
	union {
#if defined(__WIN32__) && !defined(__SYMBIAN32__)
	    struct {
		int   append;
		void *h;
		struct {
		    void *data;
		    int size;
		    int left;
		} buffer;
	    } win32io;
#endif
#ifdef HAVE_STDIO_H 
	    struct {
		int autoclose;
	 	FILE *fp;
	    } stdio;
#endif
	    struct {
		Uint8 *base;
	 	Uint8 *here;
		Uint8 *stop;
	    } mem;
	    struct {
		void *data1;
	    } unknown;
	} hidden;

} SDL_RWops;


/** @name Functions to create SDL_RWops structures from various data sources */
/*@{*/

extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFile(const char *file, const char *mode);

#ifdef HAVE_STDIO_H
extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFP(FILE *fp, int autoclose);
#endif

extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromMem(void *mem, int size);
extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromConstMem(const void *mem, int size);

extern DECLSPEC SDL_RWops * SDLCALL SDL_AllocRW(void);
extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops *area);

/*@}*/

/** @name Seek Reference Points */
/*@{*/
#define RW_SEEK_SET	0	/**< Seek from the beginning of data */
#define RW_SEEK_CUR	1	/**< Seek relative to current read point */
#define RW_SEEK_END	2	/**< Seek relative to the end of data */
/*@}*/

/** @name Macros to easily read and write from an SDL_RWops structure */
/*@{*/
#define SDL_RWseek(ctx, offset, whence)	(ctx)->seek(ctx, offset, whence)
#define SDL_RWtell(ctx)			(ctx)->seek(ctx, 0, RW_SEEK_CUR)
#define SDL_RWread(ctx, ptr, size, n)	(ctx)->read(ctx, ptr, size, n)
#define SDL_RWwrite(ctx, ptr, size, n)	(ctx)->write(ctx, ptr, size, n)
#define SDL_RWclose(ctx)		(ctx)->close(ctx)
/*@}*/

/** @name Read an item of the specified endianness and return in native format */
/*@{*/
extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops *src);
extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops *src);
extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops *src);
extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops *src);
extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops *src);
extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops *src);
/*@}*/

/** @name Write an item of native format to the specified endianness */
/*@{*/
extern DECLSPEC int SDLCALL SDL_WriteLE16(SDL_RWops *dst, Uint16 value);
extern DECLSPEC int SDLCALL SDL_WriteBE16(SDL_RWops *dst, Uint16 value);
extern DECLSPEC int SDLCALL SDL_WriteLE32(SDL_RWops *dst, Uint32 value);
extern DECLSPEC int SDLCALL SDL_WriteBE32(SDL_RWops *dst, Uint32 value);
extern DECLSPEC int SDLCALL SDL_WriteLE64(SDL_RWops *dst, Uint64 value);
extern DECLSPEC int SDLCALL SDL_WriteBE64(SDL_RWops *dst, Uint64 value);
/*@}*/

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"

#endif /* _SDL_rwops_h */
Commit	Line	Data
e14743d1	1	/*
	2	SDL - Simple DirectMedia Layer
	3	Copyright (C) 1997-2009 Sam Lantinga
	4
	5	This library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
	9
	10	This library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Lesser General Public License for more details.
	14
	15	You should have received a copy of the GNU Lesser General Public
	16	License along with this library; if not, write to the Free Software
	17	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	18
	19	Sam Lantinga
	20	slouken@libsdl.org
	21	*/
	22
	23	/** @file SDL_rwops.h
	24	* This file provides a general interface for SDL to read and write
	25	* data sources. It can easily be extended to files, memory, etc.
	26	*/
	27
	28	#ifndef _SDL_rwops_h
	29	#define _SDL_rwops_h
	30
	31	#include "SDL_stdinc.h"
	32	#include "SDL_error.h"
	33
	34	#include "begin_code.h"
	35	/* Set up for C function definitions, even when using C++ */
	36	#ifdef __cplusplus
	37	extern "C" {
	38	#endif
	39
	40	/** This is the read/write operation structure -- very basic */
	41
	42	typedef struct SDL_RWops {
	43	/** Seek to 'offset' relative to whence, one of stdio's whence values:
	44	* SEEK_SET, SEEK_CUR, SEEK_END
	45	* Returns the final offset in the data source.
	46	*/
	47	int (SDLCALL seek)(struct SDL_RWops context, int offset, int whence);
	48
	49	/** Read up to 'maxnum' objects each of size 'size' from the data
	50	* source to the area pointed at by 'ptr'.
	51	* Returns the number of objects read, or -1 if the read failed.
	52	*/
	53	int (SDLCALL read)(struct SDL_RWops context, void *ptr, int size, int maxnum);
	54
	55	/** Write exactly 'num' objects each of size 'objsize' from the area
	56	* pointed at by 'ptr' to data source.
	57	* Returns 'num', or -1 if the write failed.
	58	*/
	59	int (SDLCALL write)(struct SDL_RWops context, const void *ptr, int size, int num);
	60
	61	/** Close and free an allocated SDL_FSops structure */
	62	int (SDLCALL close)(struct SDL_RWops context);
	63
	64	Uint32 type;
65	union {
66	#if defined(__WIN32__) && !defined(__SYMBIAN32__)
67	struct {
68	int append;
69	void *h;
70	struct {
71	void *data;
72	int size;
73	int left;
74	} buffer;
75	} win32io;
76	#endif
77	#ifdef HAVE_STDIO_H
78	struct {
79	int autoclose;
80	FILE *fp;
81	} stdio;
82	#endif
83	struct {
84	Uint8 *base;
85	Uint8 *here;
86	Uint8 *stop;
87	} mem;
88	struct {
89	void *data1;
90	} unknown;
91	} hidden;
92
93	} SDL_RWops;
94
95
96	/** @name Functions to create SDL_RWops structures from various data sources */
97	/@{/
98
99	extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFile(const char file, const char mode);
100
101	#ifdef HAVE_STDIO_H
102	extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromFP(FILE *fp, int autoclose);
103	#endif
104
105	extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromMem(void *mem, int size);
106	extern DECLSPEC SDL_RWops * SDLCALL SDL_RWFromConstMem(const void *mem, int size);
107
108	extern DECLSPEC SDL_RWops * SDLCALL SDL_AllocRW(void);
109	extern DECLSPEC void SDLCALL SDL_FreeRW(SDL_RWops *area);
110
111	/@}/
112
113	/** @name Seek Reference Points */
114	/@{/
115	#define RW_SEEK_SET 0 /*< Seek from the beginning of data /
116	#define RW_SEEK_CUR 1 /*< Seek relative to current read point /
117	#define RW_SEEK_END 2 /*< Seek relative to the end of data /
118	/@}/
119
120	/** @name Macros to easily read and write from an SDL_RWops structure */
121	/@{/
122	#define SDL_RWseek(ctx, offset, whence) (ctx)->seek(ctx, offset, whence)
123	#define SDL_RWtell(ctx) (ctx)->seek(ctx, 0, RW_SEEK_CUR)
124	#define SDL_RWread(ctx, ptr, size, n) (ctx)->read(ctx, ptr, size, n)
125	#define SDL_RWwrite(ctx, ptr, size, n) (ctx)->write(ctx, ptr, size, n)
126	#define SDL_RWclose(ctx) (ctx)->close(ctx)
127	/@}/
128
129	/** @name Read an item of the specified endianness and return in native format */
130	/@{/
131	extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops *src);
132	extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops *src);
133	extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops *src);
134	extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops *src);
135	extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops *src);
136	extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops *src);
137	/@}/
138
139	/** @name Write an item of native format to the specified endianness */
140	/@{/
141	extern DECLSPEC int SDLCALL SDL_WriteLE16(SDL_RWops *dst, Uint16 value);
142	extern DECLSPEC int SDLCALL SDL_WriteBE16(SDL_RWops *dst, Uint16 value);
143	extern DECLSPEC int SDLCALL SDL_WriteLE32(SDL_RWops *dst, Uint32 value);
144	extern DECLSPEC int SDLCALL SDL_WriteBE32(SDL_RWops *dst, Uint32 value);
145	extern DECLSPEC int SDLCALL SDL_WriteLE64(SDL_RWops *dst, Uint64 value);
146	extern DECLSPEC int SDLCALL SDL_WriteBE64(SDL_RWops *dst, Uint64 value);
147	/@}/
148
149	/* Ends C function definitions when using C++ */
150	#ifdef __cplusplus
151	}
152	#endif
153	#include "close_code.h"
154
155	#endif /* _SDL_rwops_h */