libcsupport/src/access.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup libcsupport
0007  *
0008  * @brief access() - POSIX 1003.1b 5.6.3 - File Accessibility
0009  */
0010
0011 /*
0012  *  COPYRIGHT (c) 1989-1999.
0013  *  On-Line Applications Research Corporation (OAR).
0014  *
0015  * Redistribution and use in source and binary forms, with or without
0016  * modification, are permitted provided that the following conditions
0017  * are met:
0018  * 1. Redistributions of source code must retain the above copyright
0019  *    notice, this list of conditions and the following disclaimer.
0020  * 2. Redistributions in binary form must reproduce the above copyright
0021  *    notice, this list of conditions and the following disclaimer in the
0022  *    documentation and/or other materials provided with the distribution.
0023  *
0024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0027  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0028  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0029  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0030  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0031  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0032  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0033  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0034  * POSSIBILITY OF SUCH DAMAGE.
0035  */
0036
0037 #ifdef HAVE_CONFIG_H
0038 #include "config.h"
0039 #endif
0040
0041 #include <unistd.h>
0042 #include <fcntl.h>
0043 #include <sys/stat.h>
0044
0045 int access(
0046   const char *path,
0047   int         amode
0048 )
0049 {
0050   struct stat statbuf;
0051
0052   if ( stat(path, &statbuf) )
0053     return -1;
0054
0055   if ( amode & R_OK ) {
0056     if (!( statbuf.st_mode & S_IREAD ))
0057       return -1;
0058   }
0059
0060   if ( amode & W_OK ) {
0061     if ( !( statbuf.st_mode & S_IWRITE ) )
0062       return -1;
0063   }
0064
0065   if ( amode & X_OK ) {
0066     if ( !( statbuf.st_mode & S_IEXEC ) )
0067       return -1;
0068   }
0069
0070   return 0;
0071 }