freebsd-dev/libexec/rtld-elf/rtld_lock.h
Konstantin Belousov 08bfbd4359 rtld: workaround for broken ABI
Right now, libthr does not initialize RtldLockInfo.rtli_version when calling
_rtld_thread_init(), which makes versioning the interface troublesome.

Add a workaround: if the calling object of _rtld_thread_init() exports
the "_pli_rtli_version" symbol, then consider rtli_version initialized.
Otherwise, forcibly set it to RTLI_VERSION_ONE, currently defined as
RTLI_VERSION.

Export "_pli_rtli_version" from libthr and properly initialize rtli_version.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29633
2021-04-10 17:33:33 +03:00

86 lines
2.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright 2003 Alexander Kabaev.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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 AUTHOR ``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 AUTHOR 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.
*
* $FreeBSD$
*/
#ifndef _RTLD_LOCK_H_
#define _RTLD_LOCK_H_
#define RTLI_VERSION_ONE 0x01
#define RTLI_VERSION 0x01
#define MAX_RTLD_LOCKS 8
struct RtldLockInfo
{
unsigned int rtli_version;
void *(*lock_create)(void);
void (*lock_destroy)(void *);
void (*rlock_acquire)(void *);
void (*wlock_acquire)(void *);
void (*lock_release)(void *);
int (*thread_set_flag)(int);
int (*thread_clr_flag)(int);
void (*at_fork)(void);
};
#if defined(IN_RTLD) || defined(PTHREAD_KERNEL)
void _rtld_thread_init(struct RtldLockInfo *) __exported;
void _rtld_atfork_pre(int *) __exported;
void _rtld_atfork_post(int *) __exported;
#endif /* IN_RTLD || PTHREAD_KERNEL */
#ifdef IN_RTLD
struct rtld_lock;
typedef struct rtld_lock *rtld_lock_t;
extern rtld_lock_t rtld_bind_lock;
extern rtld_lock_t rtld_libc_lock;
extern rtld_lock_t rtld_phdr_lock;
extern struct RtldLockInfo lockinfo;
#define RTLD_LOCK_UNLOCKED 0
#define RTLD_LOCK_RLOCKED 1
#define RTLD_LOCK_WLOCKED 2
struct Struct_RtldLockState;
typedef struct Struct_RtldLockState RtldLockState;
void rlock_acquire(rtld_lock_t, RtldLockState *);
void wlock_acquire(rtld_lock_t, RtldLockState *);
void lock_release(rtld_lock_t, RtldLockState *);
void lock_upgrade(rtld_lock_t, RtldLockState *);
void lock_restart_for_upgrade(RtldLockState *);
#endif /* IN_RTLD */
#endif