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#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <unistd.h>
#include <stdio.h>
#include <iorpg.h>
#include "cache.h"
#include "file_allocation_table.h"
#include "bit_ops.h"
#include "filetime.h"
#include "fatfile.h"
// origin fread/fwrite do not take advantage of continuous read/write function of SD/NAND,
// it looks like the third parameter to _FAT_read_r()/_FAT_write_r() is a fixed '2'
// so they are much slower than these two....
// due to behavior of _FAT_read_r()/_FAT_write_r(),
// FAT should have a at least 8192 cluster size to get better performance,
// 16K or larger cluster size can get the best performance.
int freadex( void * buffer, int _size, int _n, FILE * f )
{
if( 0 == _n )
return 0;
dbg_printf("freadx %d\n", _n );
struct _reent r;
int ret = _FAT_read_r( &r, (int)f->_file + 8, buffer, _size * _n );
errno = r._errno;
return ret;
}
int fwriteex( const void * buffer, int _size, int _n, FILE * f )
{
if( 0 == _n )
return 0;
dbg_printf("fwritex new %d\n", _n );
struct _reent r;
int ret = _FAT_write_r( &r, (int)f->_file + 8, buffer, _size * _n );
errno = r._errno;
return ret;
}
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