usr/src/lib/libc/port/gen/fdopendir.c

   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
  39 #include "lint.h"
  40 #include <mtlib.h>
  41 #include <dirent.h>
  42 #include <sys/stat.h>
  43 #include <fcntl.h>
  44 #include <stdlib.h>
  45 #include <unistd.h>
  46 #include <errno.h>
  47 #include "libc.h"
  48
  49 DIR *
  50 fdopendir(int fd)
  51 {
  52         private_DIR *pdirp = lmalloc(sizeof (*pdirp));
  53         DIR *dirp = (DIR *)pdirp;
  54         void *buf = lmalloc(DIRBUF);
  55         int error = 0;
  56         struct stat64 sbuf;
  57
  58         if (pdirp == NULL || buf == NULL)
  59                 goto fail;
  60         /*
  61          * POSIX mandated behavior
  62          * close on exec if using file descriptor
  63          */
  64         if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0)
  65                 goto fail;
  66         if (fstat64(fd, &sbuf) < 0)
  67                 goto fail;
  68         if ((sbuf.st_mode & S_IFMT) != S_IFDIR) {
  69                 error = ENOTDIR;
  70                 goto fail;
  71         }
  72         dirp->dd_buf = buf;
  73         dirp->dd_fd = fd;
  74         dirp->dd_loc = 0;
  75         dirp->dd_size = 0;
  76         (void) mutex_init(&pdirp->dd_lock, USYNC_THREAD, NULL);
  77         return (dirp);
  78
  79 fail:
  80         if (pdirp != NULL)
  81                 lfree(pdirp, sizeof (*pdirp));
  82         if (buf != NULL)
  83                 lfree(buf, DIRBUF);
  84         if (error)
  85                 errno = error;
  86         return (NULL);
  87 }
  88
  89 int
  90 dirfd(DIR *dirp)
  91 {
  92         return (dirp->dd_fd);
  93 }