platform_bionic/libc/bionic/flistxattr.cpp
Elliott Hughes b82f5cfeb2 Improve <sys/xattr.h> coverage.
Also fix a comment copy & paste mistake and some formatting.

Test: treehugger
Change-Id: I0af3ab2eb4f180f86b0ab7d2af260f0f30692fdd
2021-03-08 14:09:43 -08:00

58 lines
2.1 KiB
C++

/*
* 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 <sys/stat.h>
#include <sys/types.h>
#include <sys/xattr.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include "private/FdPath.h"
extern "C" ssize_t __flistxattr(int, char*, size_t);
ssize_t flistxattr(int fd, char* list, size_t size) {
int saved_errno = errno;
ssize_t result = __flistxattr(fd, list, size);
if (result != -1 || errno != EBADF) {
return result;
}
// fd could be an O_PATH file descriptor, and the kernel
// may not directly support flistxattr() on such a file descriptor.
// Use /proc/self/fd instead to emulate this support.
int fd_flag = fcntl(fd, F_GETFL);
if (fd_flag == -1 || (fd_flag & O_PATH) == 0) {
errno = EBADF;
return -1;
}
errno = saved_errno;
return listxattr(FdPath(fd).c_str(), list, size);
}