src/defaults/default_readv.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @brief Default Read IO Vector Handler
0007  *
0008  * @ingroup LibIOFSHandler
0009  */
0010
0011 /*
0012  * COPYRIGHT (c) 1989-2011.
0013  * On-Line Applications Research Corporation (OAR).
0014  *
0015  * Copyright (c) 2013 embedded brains GmbH & Co. KG
0016  *
0017  * Redistribution and use in source and binary forms, with or without
0018  * modification, are permitted provided that the following conditions
0019  * are met:
0020  * 1. Redistributions of source code must retain the above copyright
0021  *    notice, this list of conditions and the following disclaimer.
0022  * 2. Redistributions in binary form must reproduce the above copyright
0023  *    notice, this list of conditions and the following disclaimer in the
0024  *    documentation and/or other materials provided with the distribution.
0025  *
0026  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0027  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0028  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0029  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0030  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0031  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0032  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0033  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0034  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0035  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0036  * POSSIBILITY OF SUCH DAMAGE.
0037  */
0038
0039 #ifdef HAVE_CONFIG_H
0040 #include "config.h"
0041 #endif
0042
0043 #include <rtems/libio_.h>
0044
0045 ssize_t rtems_filesystem_default_readv(
0046   rtems_libio_t      *iop,
0047   const struct iovec *iov,
0048   int                 iovcnt,
0049   ssize_t             total
0050 )
0051 {
0052   int v;
0053
0054   total = 0;
0055
0056   for ( v = 0 ; v < iovcnt ; ++v ) {
0057     size_t len = iov[ v ].iov_len;
0058
0059     if ( len > 0 ) {
0060       ssize_t bytes = ( *iop->pathinfo.handlers->read_h )(
0061         iop,
0062         iov[ v ].iov_base,
0063         len
0064       );
0065
0066       if ( bytes < 0 )
0067         return -1;
0068
0069       total += bytes;
0070
0071       if ( bytes != ( ssize_t ) len )
0072         break;
0073     }
0074   }
0075
0076   return total;
0077 }