glibc/sysdeps/unix/sysv/linux/tst-mount-compile.py
Adhemerval Zanella 774058d729 linux: Fix sys/mount.h usage with kernel headers
Now that kernel exports linux/mount.h and includes it on linux/fs.h,
its definitions might clash with glibc exports sys/mount.h.  To avoid
the need to rearrange the Linux header to be always after glibc one,
the glibc sys/mount.h is changed to:

  1. Undefine the macros also used as enum constants.  This covers prior
     inclusion of <linux/mount.h> (for instance MS_RDONLY).

  2. Include <linux/mount.h> based on the usual __has_include check
     (needs to use __has_include ("linux/mount.h") to paper over GCC
     bugs.

  3. Define enum fsconfig_command only if FSOPEN_CLOEXEC is not defined.
     (FSOPEN_CLOEXEC should be a very close proxy.)

  4. Define struct mount_attr if MOUNT_ATTR_SIZE_VER0 is not defined.
     (Added in the same commit on the Linux side.)

This patch also adds some tests to check if including linux/fs.h and
linux/mount.h after and before sys/mount.h does work.

Checked on x86_64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-08-12 09:15:28 -03:00

67 lines
2.3 KiB
Python
Executable File

#!/usr/bin/python3
# Check if glibc provided sys/mount.h can be used along related kernel
# headers.
# Copyright (C) 2022 Free Software Foundation, Inc.
# This file is part of the GNU C Library.
#
# The GNU C Library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# The GNU C Library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with the GNU C Library; if not, see
# <https://www.gnu.org/licenses/>.
import argparse
import sys
import glibcextract
def main():
"""The main entry point."""
parser = argparse.ArgumentParser(
description='Check if glibc provided sys/mount.h can be '
' used along related kernel headers.')
parser.add_argument('--cc', metavar='CC',
help='C compiler (including options) to use')
args = parser.parse_args()
if glibcextract.compile_c_snippet(
'#include <linux/mount.h>',
args.cc).returncode != 0:
sys.exit (77)
def check(testname, snippet):
# Add -Werror to catch macro redefinitions and _ISOMAC to avoid
# internal glibc definitions.
r = glibcextract.compile_c_snippet(snippet, args.cc,
'-Werror -D_ISOMAC')
if r.returncode != 0:
print('error: test {}:\n{}'.format(testname, r.output.decode()))
return r.returncode
status = max(
check("sys/mount.h + linux/mount.h",
"#include <sys/mount.h>\n"
"#include <linux/mount.h>"),
check("sys/mount.h + linux/fs.h",
"#include <sys/mount.h>\n"
"#include <linux/fs.h>"),
check("linux/mount.h + sys/mount.h",
"#include <linux/mount.h>\n"
"#include <sys/mount.h>"),
check("linux/fs.h + sys/mount.h",
"#include <linux/fs.h>\n"
"#include <sys/mount.h>"))
sys.exit(status)
if __name__ == '__main__':
main()