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/*-
* Copyright (c) 2002 Daniel M. Eischen <deischen@freebsd.org>
* 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 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 AUTHOR 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sysent.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/signalvar.h>
#include <sys/ucontext.h>
/*
* The first two fields of a ucontext_t are the signal mask and the machine
* context. The next field is uc_link; we want to avoid destroying the link
* when copying out contexts.
*/
#define UC_COPY_SIZE offsetof(ucontext_t, uc_link)
#ifndef _SYS_SYSPROTO_H_
struct getcontext_args {
struct __ucontext *ucp;
}
struct setcontext_args {
const struct __ucontext_t *ucp;
}
struct swapcontext_args {
struct __ucontext *oucp;
const struct __ucontext_t *ucp;
}
#endif
int
getcontext(struct thread *td, struct getcontext_args *uap)
{
ucontext_t uc;
int ret;
if (uap->ucp == NULL)
ret = EINVAL;
else {
get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
PROC_LOCK(td->td_proc);
uc.uc_sigmask = td->td_sigmask;
PROC_UNLOCK(td->td_proc);
ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
}
return (ret);
}
int
setcontext(struct thread *td, struct setcontext_args *uap)
{
ucontext_t uc;
int ret;
if (uap->ucp == NULL)
ret = EINVAL;
else {
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
if (ret == 0) {
ret = set_mcontext(td, &uc.uc_mcontext);
if (ret == 0) {
SIG_CANTMASK(uc.uc_sigmask);
PROC_LOCK(td->td_proc);
td->td_sigmask = uc.uc_sigmask;
PROC_UNLOCK(td->td_proc);
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
int
swapcontext(struct thread *td, struct swapcontext_args *uap)
{
ucontext_t uc;
int ret;
if (uap->oucp == NULL || uap->ucp == NULL)
ret = EINVAL;
else {
get_mcontext(td, &uc.uc_mcontext, GET_MC_CLEAR_RET);
PROC_LOCK(td->td_proc);
uc.uc_sigmask = td->td_sigmask;
PROC_UNLOCK(td->td_proc);
ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
if (ret == 0) {
ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
if (ret == 0) {
ret = set_mcontext(td, &uc.uc_mcontext);
if (ret == 0) {
SIG_CANTMASK(uc.uc_sigmask);
PROC_LOCK(td->td_proc);
td->td_sigmask = uc.uc_sigmask;
PROC_UNLOCK(td->td_proc);
}
}
}
}
return (ret == 0 ? EJUSTRETURN : ret);
}
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