xref: /illumos-gate/usr/src/lib/libc/port/gen/fdopendir.c (revision b6c3f786)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * fdopendir, dirfd -- C library extension routines
31  *
32  * We use lmalloc()/lfree() rather than malloc()/free() in
33  * order to allow opendir()/readdir()/closedir() to be called
34  * while holding internal libc locks.
35  */
36 
37 #pragma weak fdopendir = _fdopendir
38 #pragma weak dirfd = _dirfd
39 
40 #include "synonyms.h"
41 #include <mtlib.h>
42 #include <dirent.h>
43 #include <sys/stat.h>
44 #include <fcntl.h>
45 #include <stdlib.h>
46 #include <unistd.h>
47 #include <errno.h>
48 #include "libc.h"
49 
50 DIR *
51 fdopendir(int fd)
52 {
53 	private_DIR *pdirp = lmalloc(sizeof (*pdirp));
54 	DIR *dirp = (DIR *)pdirp;
55 	void *buf = lmalloc(DIRBUF);
56 	int error = 0;
57 	struct stat64 sbuf;
58 
59 	if (pdirp == NULL || buf == NULL)
60 		goto fail;
61 	/*
62 	 * POSIX mandated behavior
63 	 * close on exec if using file descriptor
64 	 */
65 	if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0)
66 		goto fail;
67 	if (fstat64(fd, &sbuf) < 0)
68 		goto fail;
69 	if ((sbuf.st_mode & S_IFMT) != S_IFDIR) {
70 		error = ENOTDIR;
71 		goto fail;
72 	}
73 	dirp->dd_buf = buf;
74 	dirp->dd_fd = fd;
75 	dirp->dd_loc = 0;
76 	dirp->dd_size = 0;
77 	(void) mutex_init(&pdirp->dd_lock, USYNC_THREAD, NULL);
78 	return (dirp);
79 
80 fail:
81 	if (pdirp != NULL)
82 		lfree(pdirp, sizeof (*pdirp));
83 	if (buf != NULL)
84 		lfree(buf, DIRBUF);
85 	if (error)
86 		errno = error;
87 	return (NULL);
88 }
89 
90 int
91 dirfd(DIR *dirp)
92 {
93 	return (dirp->dd_fd);
94 }
95