33 lines
676 B
C
33 lines
676 B
C
/*
|
|
* Copyright (C) 2020 Embecosm Limited
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
#include <machine/syscall.h>
|
|
#include <errno.h>
|
|
#include <sys/types.h>
|
|
#include "semihost_syscall.h"
|
|
#include "semihost_fdtable.h"
|
|
|
|
/* Read from a file. */
|
|
ssize_t _read (int file, void *ptr, size_t len)
|
|
{
|
|
struct fdentry *fd =__get_fdentry (file);
|
|
long data_block[3];
|
|
long res;
|
|
|
|
if (fd == NULL)
|
|
return -1;
|
|
|
|
data_block[0] = fd->handle;
|
|
data_block[1] = (long) ptr;
|
|
data_block[2] = len;
|
|
res = syscall_errno (SEMIHOST_read, data_block);
|
|
if (res >= 0)
|
|
{
|
|
ssize_t bytes_read = len - res;
|
|
fd->pos += bytes_read;
|
|
return bytes_read;
|
|
}
|
|
return -1;
|
|
}
|