Subversion Repositories openrisc_2011-10-31

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

//

//      dir.cxx

//

//      Fileio directory support

//

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

//####ECOSGPLCOPYRIGHTBEGIN####

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

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

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

//

// 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 directory support

// Description:         Support for directory operations.

//                      

//              

//              

//

//####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 <dirent.h>                    // struct dirent

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

#define DIROPEN_RETURN_ERR( err )               \

CYG_MACRO_START                                 \

    errno = err;                                \

    CYG_REPORT_RETVAL( NULL );                  \

    return NULL;                                \

CYG_MACRO_END

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

// Implement filesystem locking protocol. 

#define LOCK_FS( _mte_ )  {                             \

   CYG_ASSERT(_mte_ != NULL, "Bad mount table entry");  \

   cyg_fs_lock( _mte_, (_mte_)->fs->syncmode);          \

}

#define UNLOCK_FS( _mte_ ) cyg_fs_unlock( _mte_, (_mte_)->fs->syncmode)

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

// Open a directory for reading

extern DIR *opendir( const char *dirname )

{

    FILEIO_ENTRY();

    CYG_CANCELLATION_POINT;

    int ret = 0;

    int fd;

    cyg_file *file;

    cyg_mtab_entry *mte = cdir_mtab_entry;

    cyg_dir dir = cdir_dir;

    const char *name = dirname;

    fd = cyg_fd_alloc(1); // Never return fd 0

    if( fd < 0 )

        DIROPEN_RETURN_ERR(EMFILE);

    file = cyg_file_alloc();

    if( file == NULL )

    {

        cyg_fd_free(fd);

        DIROPEN_RETURN_ERR(ENFILE);

    }

    ret = cyg_mtab_lookup( &dir, &name, &mte );

    if( 0 != ret )

    {

        cyg_fd_free(fd);

        cyg_file_free(file);

        DIROPEN_RETURN_ERR(ENOENT);

    }

    LOCK_FS( mte );

    ret = mte->fs->opendir( mte, dir, name, file );

    UNLOCK_FS( mte );

    if( 0 != ret )

    {

        cyg_fd_free(fd);

        cyg_file_free(file);

        DIROPEN_RETURN_ERR(ret);

    }

    file->f_flag |= CYG_FDIR|CYG_FREAD;

    file->f_mte = mte;

    file->f_syncmode = mte->fs->syncmode;

    cyg_fd_assign( fd, file );

    DIR *dirp = (DIR *)fd;

    FILEIO_RETURN_VALUE(dirp);

}

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

// Read a directory entry.

// This is the thread-unsafe version that uses a static result buffer.

// It just calls the thread-safe version to do the work.

extern struct dirent *readdir( DIR *dirp )

{

    FILEIO_ENTRY();

    static struct dirent ent;

    struct dirent *result;

    int err;

    err = readdir_r( dirp, &ent, &result );

    if( err != 0 )

    {

        errno = err;

        FILEIO_RETURN_VALUE( NULL );

    }

    FILEIO_RETURN_VALUE( result );

}

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

extern int readdir_r( DIR *dirp, struct dirent *entry, struct dirent **result )

{

    FILEIO_ENTRY();

    int fd = (int)dirp;

    ssize_t res;

    *result = NULL;

    res = read( fd, (void *)entry, sizeof(struct dirent));

    if( res < 0 )

    {

        FILEIO_RETURN_VALUE( errno );

    }

    if( res > 0 )

        *result = entry;

    FILEIO_RETURN( ENOERR );

}

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

extern void rewinddir( DIR *dirp )

{

    FILEIO_ENTRY();

    int fd = (int)dirp;

    lseek( fd, 0, SEEK_SET );

    FILEIO_RETURN_VOID();

}

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

extern int closedir( DIR *dirp )

{

    FILEIO_ENTRY();

    int fd = (int)dirp;

    int err = close( fd );

    FILEIO_RETURN_VALUE( err );

}

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

// EOF dir.cxx