dirent.c

/****************************************************************************
*
*   Copyright (c) 2010 Dave Hylands     <dhylands@gmail.com>
*
*   This program is free software; you can redistribute it and/or modify
*   it under the terms of the GNU General Public License version 2 as
*   published by the Free Software Foundation.
*
*   Alternatively, this software may be distributed under the terms of BSD
*   license.
*
*   See README and COPYING for more details.
*
****************************************************************************/
/**
*
*   @file   dirent.c
*
*   @brief  This file contains an implementation on readdir and friends
*           which works under Win32.
*
*****************************************************************************/

/* ---- Include Files ----------------------------------------------------- */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include "dirent2.h"

#include <windows.h>

/* ---- Public Variables -------------------------------------------------- */

/* ---- Private Constants and Types --------------------------------------- */

/* ---- Private Variables ------------------------------------------------- */

/* ---- Private Function Prototypes --------------------------------------- */

/* ---- Functions --------------------------------------------------------- */

/**
 * @addtogroup XXX
 * @{
 */

//***************************************************************************
/**
*   The opendir() function opens a directory stream corresponding to 
*   the directory name, and returns a pointer to the directory stream. 
*   The stream is positioned at the first entry in the directory. 
*
*   On error, NULL is returned and errno is set appropriately.
*/

DIR2 *opendir2( const char *dirName )
{
    DIR2    *dir;
    DWORD   fileAttr;

    // Validate parameters

    if ( dirName == NULL )
    {
        errno = EFAULT;
        return NULL;
    }
    if ( dirName[0] == '\0' )
    {
        errno = ENOENT;
        return NULL;
    }

    // Make sure that dirName is really a directory

    if (( fileAttr = GetFileAttributes( dirName )) == INVALID_FILE_ATTRIBUTES )
    {
        errno = ENOTDIR;
        return NULL;
    }

    if (( dir = calloc( 1, sizeof( *dir ))) == NULL )
    {
        errno = ENOMEM;
        return NULL;
    }
    if (( dir->dd_finddata = malloc( sizeof( WIN32_FIND_DATA ))) == NULL )
    {
        errno = ENOMEM;
        free( dir );
        return NULL;
    }

    // We need to pass in a pattern to FindFirstFile, so we allocate
    // memory to contain the directory passed in followed by /*

    if (( dir->dd_dirpattern = malloc( strlen( dirName ) + 3 )) == NULL )
    {
        errno = ENOMEM;
        free( dir->dd_finddata );
        free( dir );
        return NULL;
    }
    strcpy( dir->dd_dirpattern, dirName );
    strcat( dir->dd_dirpattern, "/*" );

    dir->dd_handle = 0;

    return dir;
}

//***************************************************************************
/**
*   The readdir() function returns a pointer to a dirent structure 
*   representing the next directory entry in the directory stream 
*   pointed to by dir. It returns NULL on reaching the end-of-file 
*   or if an error occurred. 
*/

struct dirent2 *readdir2( DIR2 *dir )
{
    WIN32_FIND_DATA    *fd;

    if ( dir->dd_handle == INVALID_HANDLE_VALUE )
    {
        errno = EBADF;
        return NULL;
    }

    if ( dir->dd_handle == 0 )
    {
        dir->dd_handle = FindFirstFile( dir->dd_dirpattern, dir->dd_finddata );
        if ( dir->dd_handle == INVALID_HANDLE_VALUE )
        {
            errno = 0;
            return NULL;
        }
    }
    else
    {
        if ( !FindNextFile( dir->dd_handle, dir->dd_finddata ))
        {
            if ( GetLastError() == ERROR_NO_MORE_FILES )
            {
                errno = 0;
                return NULL;
            }
        }
    }

    fd = dir->dd_finddata;

    strncpy( dir->dd_dirent.d_name, fd->cFileName, sizeof( dir->dd_dirent.d_name ));
    dir->dd_dirent.d_name[ sizeof( dir->dd_dirent.d_name ) - 1 ] = '\0';

    dir->dd_dirent.d_type = 0;

    if ( fd->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
    {
        dir->dd_dirent.d_type |= DT_DIR;
    }
    else
    {
        dir->dd_dirent.d_type |= DT_REG;
    }

    return &dir->dd_dirent;
}

//***************************************************************************
/**
*   The closedir() function closes the directory stream associated with dir. 
*   The directory stream descriptor dir is not available after this call. 
*/

int closedir2( DIR2 *dir )
{
    int     rc = 0;

    if (( dir->dd_handle == 0 ) || ( dir->dd_handle != INVALID_HANDLE_VALUE ))
    {
        if ( !FindClose( dir->dd_handle ))
        {
            errno = EBADF;
            rc = -1;
        }
        dir->dd_handle = 0;
    }

    free( dir->dd_dirpattern );
    free( dir->dd_finddata );
    free( dir );

    return rc;
}

/** @} */