1 files changed, 47 insertions, 0 deletions
diff --git a/sdk-modifications/libsrc/fs/fatfile_ex.c b/sdk-modifications/libsrc/fs/fatfile_ex.c
new file mode 100644
index 0000000..aa23fb3
--- /dev/null
+++ b/sdk-modifications/libsrc/fs/fatfile_ex.c
@@ -0,0 +1,47 @@
+#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;
+}
+