platform_bionic/libc/include/bits/ioctl.h
George Burgess IV de45dcbbab libc: silence unsigned->signed warnings with ioctl
This also tweaks cdefs to make __overloadable usable outside of
FORTIFY. It had to be FORTIFY-only before we had unmarked overload
support in clang+Bionic.

Bug: https://github.com/android-ndk/ndk/issues/402
Test: Internal master builds + `mma`. `mma` in Bionic fails if the
change to ioctl is undone.

Change-Id: Ib386b1786e1dca625e6d5a18682005adc734d9c1
2018-03-20 15:59:46 -07:00

62 lines
2.5 KiB
C

/*
* Copyright (C) 2016 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.
*/
#ifndef _BITS_IOCTL_H_
#define _BITS_IOCTL_H_
#include <sys/cdefs.h>
__BEGIN_DECLS
int ioctl(int __fd, int __request, ...);
/*
* Work around unsigned -> signed conversion warnings: many common ioctl
* constants are unsigned.
*
* Since this workaround introduces an overload to ioctl, it's possible that it
* will break existing code that takes the address of ioctl. If such a breakage
* occurs, you can work around it by either:
* - specifying a concrete, correct type for ioctl (whether it be through a cast
* in `(int (*)(int, int, ...))ioctl`, creating a temporary variable with the
* type of the ioctl you prefer, ...), or
* - defining BIONIC_IOCTL_NO_SIGNEDNESS_OVERLOAD, which will make the
* overloading go away.
*
* FIXME: __has_extension is more or less a clang version check. Remove it when
* we don't need to support old clang code.
*/
#if defined(__clang__) && __has_extension(overloadable_unmarked) && \
!defined(BIONIC_IOCTL_NO_SIGNEDNESS_OVERLOAD)
/* enable_if(1) just exists to break overloading ties. */
int ioctl(int __fd, unsigned __request, ...) __overloadable __enable_if(1, "") __RENAME(ioctl);
#endif
__END_DECLS
#endif