Subversion Repositories openrisc_2011-10-31

//==========================================================================

//

//      io.cxx

//

//      Fileio IO operations

//

//==========================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

// Copyright (C) 2002 Gary Thomas

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later version.

//

// eCos is distributed in the hope that it will be useful, but WITHOUT ANY

// WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License along

// with eCos; if not, write to the Free Software Foundation, Inc.,

// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

//

// As a special exception, if other files instantiate templates or use macros

// or inline functions from this file, or you compile this file and link it

// with other works to produce a work based on this file, this file does not

// by itself cause the resulting work to be covered by the GNU General Public

// License. However the source code for this file must still be made available

// in accordance with section (3) of the GNU General Public License.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

// at http://sources.redhat.com/ecos/ecos-license/

// -------------------------------------------

//####ECOSGPLCOPYRIGHTEND####

//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):           nickg

// Contributors:        nickg

// Date:                2000-05-25

// Purpose:             Fileio IO operations

// Description:         These are the functions that operate on open files,

//                      such as read(), write(), fstat() etc.

//              

//              

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include <pkgconf/hal.h>

#include <pkgconf/kernel.h>

#include <pkgconf/io_fileio.h>

#include <cyg/kernel/ktypes.h>         // base kernel types

#include <cyg/infra/cyg_trac.h>        // tracing macros

#include <cyg/infra/cyg_ass.h>         // assertion macros

#include <stdarg.h>                     // for fcntl()

#include "fio.h"                       // Private header

#include <cyg/kernel/mutex.hxx>        // mutex definitions

//==========================================================================

// File object locking

#define LOCK_FILE( fp ) cyg_file_lock( fp, fp->f_syncmode )

#define UNLOCK_FILE( fp ) cyg_file_unlock( fp, fp->f_syncmode )

//==========================================================================

// Common wrapper for read/write using an iovec descriptor 

// 'direction' should be O_RDONLY for readv, O_WRONLY for writev

static ssize_t

readwritev( int fd, const cyg_iovec *_iov, int iov_len, int direction )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    ssize_t cnt, len;

    int ret, _idx;

    cyg_file *fp;

    cyg_iovec iov[CYGNUM_FILEIO_IOVEC_MAX];

    if( iov_len > CYGNUM_FILEIO_IOVEC_MAX )

        FILEIO_RETURN(EINVAL);

    // Copy 'iovec' structure since it's supposed to be "const"

    // and some lower level routines might want to change it.

    // Also accumulate the length of the total I/O request

    len = 0;

    for (_idx = 0;  _idx < iov_len;  _idx++) {

        len += _iov[_idx].iov_len;

        iov[_idx].iov_base = _iov[_idx].iov_base;

        iov[_idx].iov_len = _iov[_idx].iov_len;

    }

    if( len > SSIZE_MAX )

        FILEIO_RETURN(EINVAL);

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    if( (fp->f_flag & direction) == 0 )

    {

        cyg_fp_free( fp );

        FILEIO_RETURN(EBADF);

    }

    cyg_uio uio;

    cyg_fileop_readwrite *op;

    uio.uio_iov         = iov;

    uio.uio_iovcnt      = iov_len;

    uio.uio_resid       = len;

    uio.uio_segflg      = UIO_USERSPACE;

    cnt = len;

    if( direction == O_RDONLY )

        uio.uio_rw = UIO_READ, op = fp->f_ops->fo_read;

    else

        uio.uio_rw = UIO_WRITE, op = fp->f_ops->fo_write;

    LOCK_FILE( fp );

    ret = op( fp, &uio );

    UNLOCK_FILE( fp );

    cnt -= uio.uio_resid;

    cyg_fp_free( fp );

    CYG_CANCELLATION_POINT;

    if( ret != 0 )

        FILEIO_RETURN(ret);

    FILEIO_RETURN_VALUE(cnt);

}

//==========================================================================

// Read from file

__externC ssize_t read( int fd, void *buf, size_t len )

{

    cyg_iovec _iov;

    _iov.iov_base = buf;

    _iov.iov_len = len;

    return readwritev(fd, &_iov, 1, O_RDONLY);

}

//==========================================================================

// Write to a file

__externC ssize_t write( int fd, const void *buf, size_t len )

{

    cyg_iovec _iov;

    _iov.iov_base = (void *)buf;

    _iov.iov_len = len;

    return readwritev(fd, &_iov, 1, O_WRONLY);

}

//==========================================================================

// Read via an iovec

__externC ssize_t readv( int fd, const cyg_iovec *_iov, int iov_len )

{

    return readwritev(fd, _iov, iov_len, O_RDONLY);

}

//==========================================================================

// Write via an iovec

__externC ssize_t writev( int fd, const cyg_iovec *_iov, int iov_len )

{

    return readwritev(fd, _iov, iov_len, O_WRONLY);

}

//==========================================================================

// Close a file

__externC int close( int fd )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    cyg_fp_free( fp );

    // The file's fo_close entry may be called as a side

    // effect of this operation...

    ret = cyg_fd_free( fd );

    CYG_CANCELLATION_POINT;

    FILEIO_RETURN(ret);

}

//==========================================================================

// Seek a file

__externC off_t lseek( int fd, off_t pos, int whence )

{

    FILEIO_ENTRY();

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_lseek( fp, &pos, whence );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    if( ret != 0 )

        FILEIO_RETURN(ret);

    FILEIO_RETURN_VALUE(pos);

}

//==========================================================================

// ioctl

__externC int ioctl( int fd, CYG_ADDRWORD com, CYG_ADDRWORD data )

{

    FILEIO_ENTRY();

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_ioctl( fp, com, data );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    FILEIO_RETURN(ret);

}

//==========================================================================

// fsync

__externC int fsync( int fd )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_fsync( fp, CYG_FSYNC );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    CYG_CANCELLATION_POINT;

    FILEIO_RETURN(ret);

}

//==========================================================================

// fdatasync()

__externC int fdatasync( int fd )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_fsync( fp, CYG_FDATASYNC );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    CYG_CANCELLATION_POINT;

    FILEIO_RETURN(ret);

}

//==========================================================================

// fstat

__externC int fstat( int fd, struct stat *buf )

{

    FILEIO_ENTRY();

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_fstat( fp, buf );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    FILEIO_RETURN(ret);

}

//==========================================================================

// fpathconf

__externC long fpathconf( int fd, int name )

{

    FILEIO_ENTRY();

    int ret;

    cyg_file *fp;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    struct cyg_pathconf_info info;

    info.name = name;

    info.value = 0;

    LOCK_FILE( fp );

    ret = fp->f_ops->fo_getinfo( fp, FILE_INFO_CONF, (char *)&info, sizeof(info) );

    UNLOCK_FILE( fp );

    cyg_fp_free( fp );

    if( ret != 0 )

        FILEIO_RETURN(ret);

    FILEIO_RETURN_VALUE(info.value);

}

//==========================================================================

// fcntl

__externC int fcntl( int fd, int cmd, ... )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    int ret = 0;

    cyg_file *fp;

    va_list a;

    fp = cyg_fp_get( fd );

    if( fp == NULL )

        FILEIO_RETURN(EBADF);

    va_start( a, cmd );

    switch( cmd )

    {

    case F_DUPFD:

    {

        int fda = va_arg(a, int);

        if( fda < 0 || fda >= OPEN_MAX )

        {

            errno = EBADF;

            break;

        }

        int fd2 = cyg_fd_alloc( fda );

        if( fd2 == -1 )

        {

            ret = EMFILE;

            break;

        }

        cyg_fd_assign( fd2, fp );

        break;

    }

    default:

        ret = ENOTSUP;

        break;

    }

    va_end(a);

    cyg_fp_free( fp );

    CYG_CANCELLATION_POINT;

    FILEIO_RETURN(ret);

}

//==========================================================================

// isatty()

__externC int isatty( int fd )

{

    FILEIO_ENTRY();

    int ret = 0;

    struct stat buf;

    int err;

    err = fstat( fd, &buf );

    // Any error and we return zero. If the client wants to

    // they can always pick up the error code from errno.

    if( err < 0 )

        FILEIO_RETURN_VALUE(0);

    // For now we assume that all char devices are ttys.

    // In future we may need to have a special getinfo()

    // call to decide this more specifically.

    if( S_ISCHR( buf.st_mode ) )

        ret = 1;

    FILEIO_RETURN_VALUE(ret);

}

// -------------------------------------------------------------------------

// EOF io.cxx