glue-scandir.c

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef HAVE_OPENDIR

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)scandir.c   5.10 (Berkeley) 2/23/91";
#endif /* LIBC_SCCS and not lint */

/*
 * Scan the directory dirname calling select to make a list of selected
 * directory entries then sort using qsort and compare routine dcomp.
 * Returns the number of entries and a pointer to a list of pointers to
 * struct dirent (through namelist). Returns -1 if there were any errors.
 */

#include <newlib.h>

#include <dirent.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>

/*
 * The DIRSIZ macro gives the minimum record length which will hold
 * the directory entry.  This requires the amount of space in struct dirent
 * without the d_name field, plus enough space for the name with a terminating
 * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary.
 */
#undef DIRSIZ
#ifdef _DIRENT_HAVE_D_NAMLEN
#define DIRSIZ(dp)                               \
    ((sizeof(struct dirent) - (MAXNAMLEN + 1)) + \
     (((dp)->d_namlen + 1 + 3) & ~3))
#else
#define DIRSIZ(dp)                               \
    ((sizeof(struct dirent) - (MAXNAMLEN + 1)) + \
     ((strlen((dp)->d_name) + 1 + 3) & ~3))
#endif

#ifndef __P
#define __P(args) ()
#endif

int scandir(dirname, namelist, select, dcomp) const char *dirname;
struct dirent ***namelist;
int(*select) __P((struct dirent *) );
int(*dcomp) __P((const void *, const void *) );
{
    register struct dirent *d, *p, **names;
    register size_t nitems;
    struct stat stb;
    size_t arraysz;
    DIR *dirp;

    if ((dirp = opendir(dirname)) == NULL)
        return (-1);
    if (fstat(dirp->fd, &stb) < 0)
        return (-1);

    /*
     * estimate the array size by taking the size of the directory file
     * and dividing it by a multiple of the minimum size entry.
     */
    arraysz = (stb.st_size / 24);
    names = (struct dirent **) malloc(arraysz * sizeof(struct dirent *));
    if (names == NULL)
        return (-1);

    nitems = 0;
    while ((d = readdir(dirp)) != NULL)
    {
        if (select != NULL && !(*select)(d))
            continue; /* just selected names */
        /*
         * Make a minimum size copy of the data
         */
        p = (struct dirent *) malloc(DIRSIZ(d));
        if (p == NULL)
            return (-1);
        p->d_ino = d->d_ino;
// p->d_reclen = d->d_reclen;
#ifdef _DIRENT_HAVE_D_NAMLEN
        p->d_namlen = d->d_namlen;
        bcopy(d->d_name, p->d_name, p->d_namlen + 1);
#else
        strcpy(p->d_name, d->d_name);
#endif
        /*
         * Check to make sure the array has space left and
         * realloc the maximum size.
         */
        if (++nitems >= arraysz)
        {
            if (fstat(dirp->fd, &stb) < 0)
                return (-1); /* just might have grown */
            arraysz = stb.st_size / 12;
            names = (struct dirent **) realloc(
                (char *) names, arraysz * sizeof(struct dirent *));
            if (names == NULL)
                return (-1);
        }
        names[nitems - 1] = p;
    }
    closedir(dirp);
    if (nitems && dcomp != NULL)
        qsort(names, nitems, sizeof(struct dirent *), dcomp);
    *namelist = names;
    return (nitems);
}

/*
 * Alphabetic order comparison routine for those who want it.
 */
int alphasort(d1, d2) const struct dirent **d1;
const struct dirent **d2;
{
    return (strcmp((*d1)->d_name, (*d2)->d_name));
}

#endif /* ! HAVE_OPENDIR */