RetroArch/libretro-common/include/file/nbio.h
2020-01-31 15:43:42 +01:00

125 lines
3.6 KiB
C

/* Copyright (C) 2010-2020 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this file (nbio.h).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef __LIBRETRO_SDK_NBIO_H
#define __LIBRETRO_SDK_NBIO_H
#include <stddef.h>
#include <boolean.h>
#include <retro_common_api.h>
RETRO_BEGIN_DECLS
#ifndef NBIO_READ
#define NBIO_READ 0
#endif
#ifndef NBIO_WRITE
#define NBIO_WRITE 1
#endif
#ifndef NBIO_UPDATE
#define NBIO_UPDATE 2
#endif
/* these two are blocking; nbio_iterate always returns true, but that operation (or something earlier) may take arbitrarily long */
#ifndef BIO_READ
#define BIO_READ 3
#endif
#ifndef BIO_WRITE
#define BIO_WRITE 4
#endif
typedef struct nbio_intf
{
void *(*open)(const char * filename, unsigned mode);
void (*begin_read)(void *data);
void (*begin_write)(void *data);
bool (*iterate)(void *data);
void (*resize)(void *data, size_t len);
void *(*get_ptr)(void *data, size_t* len);
void (*cancel)(void *data);
void (*free)(void *data);
/* Human readable string. */
const char *ident;
} nbio_intf_t;
/*
* Creates an nbio structure for performing the
* given operation on the given file.
*/
void *nbio_open(const char * filename, unsigned mode);
/*
* Starts reading the given file. When done, it will be available in nbio_get_ptr.
* Can not be done if the structure was created with {N,}BIO_WRITE.
*/
void nbio_begin_read(void *data);
/*
* Starts writing to the given file. Before this, you should've copied the data to nbio_get_ptr.
* Can not be done if the structure was created with {N,}BIO_READ.
*/
void nbio_begin_write(void *data);
/*
* Performs part of the requested operation, or checks how it's going.
* When it returns true, it's done.
*/
bool nbio_iterate(void *data);
/*
* Resizes the file up to the given size; cannot shrink.
* Can not be done if the structure was created with {N,}BIO_READ.
*/
void nbio_resize(void *data, size_t len);
/*
* Returns a pointer to the file data. Writable only if structure was not created with {N,}BIO_READ.
* If any operation is in progress, the pointer will be NULL, but len will still be correct.
*/
void* nbio_get_ptr(void *data, size_t* len);
/*
* Stops any pending operation, allowing the object to be freed.
*/
void nbio_cancel(void *data);
/*
* Deletes the nbio structure and its associated pointer.
*/
void nbio_free(void *data);
RETRO_END_DECLS
#endif