/**
* This routine processes the read() system call.
*
* @param iop
* @param buffer
* @param count
* @return int
*/
static ssize_t
rtems_rfs_rtems_file_read (rtems_libio_t* iop,
void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
uint8_t* data = buffer;
ssize_t read = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_READ))
printf("rtems-rfs: file-read: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
if (pos < rtems_rfs_file_size (file))
{
while (count)
{
size_t size;
rc = rtems_rfs_file_io_start (file, &size, true);
if (rc > 0)
{
read = rtems_rfs_rtems_error ("file-read: read: io-start", rc);
break;
}
if (size == 0)
break;
if (size > count)
size = count;
memcpy (data, rtems_rfs_file_data (file), size);
data += size;
count -= size;
read += size;
rc = rtems_rfs_file_io_end (file, size, true);
if (rc > 0)
{
read = rtems_rfs_rtems_error ("file-read: read: io-end", rc);
break;
}
}
}
if (read >= 0)
iop->offset = pos + read;
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return read;
}
/**
* This routine processes the write() system call.
*
* @param iop
* @param buffer
* @param count
* @return ssize_t
*/
static ssize_t
rtems_rfs_rtems_file_write (rtems_libio_t* iop,
const void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
rtems_rfs_pos file_size;
const uint8_t* data = buffer;
ssize_t write = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_WRITE))
printf("rtems-rfs: file-write: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
file_size = rtems_rfs_file_size (file);
if (pos > file_size)
{
/*
* If the iop position is past the physical end of the file we need to set
* the file size to the new length before writing. The
* rtems_rfs_file_io_end() will grow the file subsequently.
*/
rc = rtems_rfs_file_set_size (file, pos);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write extend", rc);
}
rtems_rfs_file_set_bpos (file, pos);
}
else if (pos < file_size && rtems_libio_iop_is_append(iop))
{
pos = file_size;
rc = rtems_rfs_file_seek (file, pos, &pos);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write append seek", rc);
}
}
while (count)
{
size_t size = count;
rc = rtems_rfs_file_io_start (file, &size, false);
if (rc)
{
/*
* If we have run out of space and have written some data return that
* amount first as the inode will have accounted for it. This means
* there was no error and the return code from can be ignored.
*/
if (!write)
write = rtems_rfs_rtems_error ("file-write: write open", rc);
break;
}
if (size > count)
size = count;
memcpy (rtems_rfs_file_data (file), data, size);
data += size;
count -= size;
write += size;
rc = rtems_rfs_file_io_end (file, size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write close", rc);
break;
}
}
if (write >= 0)
iop->offset = pos + write;
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return write;
}
/**
* This routine processes the write() system call.
*
* @param iop
* @param buffer
* @param count
* @return ssize_t
*/
static ssize_t
rtems_rfs_rtems_file_write (rtems_libio_t* iop,
const void* buffer,
size_t count)
{
rtems_rfs_file_handle* file = rtems_rfs_rtems_get_iop_file_handle (iop);
rtems_rfs_pos pos;
const uint8_t* data = buffer;
ssize_t write = 0;
int rc;
if (rtems_rfs_rtems_trace (RTEMS_RFS_RTEMS_DEBUG_FILE_WRITE))
printf("rtems-rfs: file-write: handle:%p count:%zd\n", file, count);
rtems_rfs_rtems_lock (rtems_rfs_file_fs (file));
pos = iop->offset;
/*
* If the iop position is past the physical end of the file we need to set
* the file size to the new length before writing. If the position equals the
* size of file we are still past the end of the file as positions number
* from 0. For a specific position we need a file that has a length of one
* more.
*/
if (pos >= rtems_rfs_file_size (file))
{
rc = rtems_rfs_file_set_size (file, pos + 1);
if (rc)
{
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return rtems_rfs_rtems_error ("file-write: write extend", rc);
}
}
rtems_rfs_file_set_bpos (file, pos);
while (count)
{
size_t size = count;
rc = rtems_rfs_file_io_start (file, &size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write open", rc);
break;
}
if (size > count)
size = count;
memcpy (rtems_rfs_file_data (file), data, size);
data += size;
count -= size;
write += size;
rc = rtems_rfs_file_io_end (file, size, false);
if (rc)
{
write = rtems_rfs_rtems_error ("file-write: write close", rc);
break;
}
}
iop->size = rtems_rfs_file_size (file);
rtems_rfs_rtems_unlock (rtems_rfs_file_fs (file));
return write;
}
