/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/

/*	  All Rights Reserved  	*/

/*

 * University Copyright- Copyright (c) 1982, 1986, 1988

 * The Regents of the University of California

 * All Rights Reserved

 *

 * University Acknowledgment- Portions of this document are derived from

 * software developed by the University of California, Berkeley, and its

 * contributors.

 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

/*

 * Based on usr/src/ucblib/libucb/port/gen/scandir.c

 */

/*

 * 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 direct (through namelist). Returns -1 if there were any errors.

 */

#include <sys/feature_tests.h>

#pragma weak _scandir = scandir

#pragma weak _alphasort = alphasort

#if !defined(_LP64)

#pragma weak _scandir64 = scandir64

#pragma weak _alphasort64 = alphasort64

#endif

#include "lint.h"

#include <dirent.h>

#include <errno.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <stdlib.h>

#include <string.h>

#include <limits.h>

#if !defined(_LP64)

int

scandir64(const char *dirname, struct dirent64 *(*namelist[]),

    int (*select)(const struct dirent64 *),

    int (*dcomp)(const struct dirent64 **, const struct dirent64 **))

{

	struct dirent64	*d, *p, **names = NULL;

	size_t	nitems = 0;

	size_t	arraysz, entlen;

	struct stat64	stb;

	DIR	*dirp;

	u_longlong_t	tmp_arraysz;

	if ((dirp = opendir(dirname)) == NULL)

		return (-1);

	if (fstat64(dirp->dd_fd, &stb) < 0)

		goto fail;

	/*

	 * estimate the array size by taking the size of the directory file

	 * and dividing it by a multiple of the minimum size entry.

	 */

	tmp_arraysz = stb.st_size / 24;	/* 24 bytes on a 64-bit system */

	if (tmp_arraysz > INT_MAX)

		arraysz = INT_MAX;

	else

		arraysz = (size_t)tmp_arraysz;

	names = malloc(arraysz * sizeof (struct dirent64 *));

	if (names == NULL)

		goto fail;

	while ((d = readdir64(dirp)) != NULL) {

		if (select != NULL && !(*select)(d))

			continue;	/* just selected names */

		entlen = d->d_reclen;

		/*

		 * Make a minimum size copy of the data

		 */

		p = malloc(entlen);

		if (p == NULL)

			goto fail;

		(void) memcpy(p, d, entlen);

		/*

		 * Check to make sure the array has space left and

		 * realloc the maximum size.

		 */

		if (nitems >= arraysz) {

			struct dirent64	**tmp;

			if (nitems == INT_MAX) {

				/* overflow */

				free(p);

				errno = EOVERFLOW;

				goto fail;

			}

			arraysz += 512;		/* no science here */

			tmp = realloc(names,

			    arraysz * sizeof (struct dirent64 *));

			if (tmp == NULL) {

				free(p);

				goto fail;

			}

			names = tmp;

		}

		names[nitems++] = p;

	}

	(void) closedir(dirp);

	if (nitems && dcomp != NULL)

		qsort(names, nitems, sizeof (struct dirent64 *),

		    (int(*)(const void *, const void *))dcomp);

	*namelist = names;

	return ((int)nitems);

fail:

	while (nitems != 0) {

		free(names[--nitems]);

	}

	if (names)

		free(names);

	(void) closedir(dirp);

	return (-1);

}

#endif

int

scandir(const char *dirname, struct dirent *(*namelist[]),

    int (*select)(const struct dirent *),

    int (*dcomp)(const struct dirent **, const struct dirent **))

{

	struct dirent	*d, *p, **names = NULL;

	size_t	nitems = 0;

	size_t	arraysz, entlen;

	struct stat64	stb;

	DIR	*dirp;

	u_longlong_t	tmp_arraysz;

	if ((dirp = opendir(dirname)) == NULL)

		return (-1);

	if (fstat64(dirp->dd_fd, &stb) < 0)

		goto fail;

	/*

	 * estimate the array size by taking the size of the directory file

	 * and dividing it by a multiple of the minimum size entry.

	 */

	tmp_arraysz = stb.st_size / 24;	/* 24 bytes on a 64-bit system */

	if (tmp_arraysz > INT_MAX)

		arraysz = INT_MAX;

	else

		arraysz = (size_t)tmp_arraysz;

	names = malloc(arraysz * sizeof (struct dirent *));

	if (names == NULL)

		goto fail;

	while ((d = readdir(dirp)) != NULL) {

		if (select != NULL && !(*select)(d))

			continue;	/* just selected names */

		entlen = d->d_reclen;

		/*

		 * Make a minimum size copy of the data

		 */

		p = malloc(entlen);

		if (p == NULL)

			goto fail;

		(void) memcpy(p, d, entlen);

		/*

		 * Check to make sure the array has space left and

		 * realloc the maximum size.

		 */

		if (nitems >= arraysz) {

			struct dirent **tmp;

			if (nitems == INT_MAX) {

				/* overflow */

				free(p);

				errno = EOVERFLOW;

				goto fail;

			}

			arraysz += 512;		/* no science here */

			tmp = realloc(names,

			    arraysz * sizeof (struct dirent *));

			if (tmp == NULL) {

				free(p);

				goto fail;

			}

			names = tmp;

		}

		names[nitems++] = p;

	}

	(void) closedir(dirp);

	if (nitems && dcomp != NULL)

		qsort(names, nitems, sizeof (struct dirent *),

		    (int(*)(const void *, const void *))dcomp);

	*namelist = names;

	return ((int)nitems);

fail:

	while (nitems != 0) {

		free(names[--nitems]);

	}

	if (names)

		free(names);

	(void) closedir(dirp);

	return (-1);

}

/*

 * Alphabetic order comparison routine for those who want it.

 */

int

alphasort(const struct dirent **d1, const struct dirent **d2)

{

	return (strcoll((*d1)->d_name,

	    (*d2)->d_name));

}

#if !defined(_LP64)

int

alphasort64(const struct dirent64 **d1, const struct dirent64 **d2)

{

	return (strcoll((*d1)->d_name,

	    (*d2)->d_name));

}

#endif