forked from Imagelibrary/rtems
73f6236bc0
IO handlers scheme that was implemented originally just to support sockets. The file system IO switch is more general and works fine.
68 lines
1.3 KiB
C
68 lines
1.3 KiB
C
/*
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* read() - POSIX 1003.1b 6.4.1 - Read From a File
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*
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* COPYRIGHT (c) 1989-1998.
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* On-Line Applications Research Corporation (OAR).
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* Copyright assigned to U.S. Government, 1994.
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*
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* The license and distribution terms for this file may be
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* found in the file LICENSE in this distribution or at
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* http://www.OARcorp.com/rtems/license.html.
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*
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* $Id$
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*/
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#include "libio_.h"
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ssize_t read(
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int fd,
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void *buffer,
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size_t count
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)
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{
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int rc; /* XXX change to a size_t when prototype is fixed */
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rtems_libio_t *iop;
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rtems_libio_check_fd( fd );
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iop = rtems_libio_iop( fd );
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rtems_libio_check_is_open(iop);
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rtems_libio_check_buffer( buffer );
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rtems_libio_check_count( count );
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rtems_libio_check_permissions( iop, LIBIO_FLAGS_READ );
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/*
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* Now process the read().
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*/
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if ( !iop->handlers->read )
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set_errno_and_return_minus_one( ENOTSUP );
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rc = (*iop->handlers->read)( iop, buffer, count );
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if ( rc > 0 )
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iop->offset += rc;
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return rc;
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}
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/*
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* _read_r
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*
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* This is the Newlib dependent reentrant version of read().
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*/
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#if defined(RTEMS_NEWLIB)
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#include <reent.h>
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_ssize_t _read_r(
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struct _reent *ptr,
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int fd,
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void *buf,
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size_t nbytes
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)
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{
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return read( fd, buf, nbytes );
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}
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#endif
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