| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * 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. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 |
| * COPYRIGHT OWNER 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. |
| */ |
| |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <errno.h> |
| |
| extern "C" int ___faccessat(int, const char*, int); |
| |
| int faccessat(int dirfd, const char* pathname, int mode, int flags) { |
| // "The mode specifies the accessibility check(s) to be performed, |
| // and is either the value F_OK, or a mask consisting of the |
| // bitwise OR of one or more of R_OK, W_OK, and X_OK." |
| if ((mode != F_OK) && ((mode & ~(R_OK | W_OK | X_OK)) != 0) && |
| ((mode & (R_OK | W_OK | X_OK)) == 0)) { |
| errno = EINVAL; |
| return -1; |
| } |
| |
| if (flags != 0) { |
| // We deliberately don't support AT_SYMLINK_NOFOLLOW, a glibc |
| // only feature which is error prone and dangerous. |
| // |
| // AT_EACCESS isn't supported either. Android doesn't have setuid |
| // programs, and never runs code with euid!=uid. It could be |
| // implemented in an expensive way, following the model at |
| // https://gitlab.com/bminor/musl/commit/0a05eace163cee9b08571d2ff9d90f5e82d9c228 |
| // but not worth it. |
| errno = EINVAL; |
| return -1; |
| } |
| |
| return ___faccessat(dirfd, pathname, mode); |
| } |