diff options
Diffstat (limited to 'sys/kern/kern_context.c')
| -rw-r--r-- | sys/kern/kern_context.c | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/sys/kern/kern_context.c b/sys/kern/kern_context.c new file mode 100644 index 0000000..1cc0eac --- /dev/null +++ b/sys/kern/kern_context.c @@ -0,0 +1,134 @@ +/*- + * 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. + * + */ +/* + * $FreeBSD$ + */ + +#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 (sizeof(sigset_t) + sizeof(mcontext_t)) + + +#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 + +/* + * MPSAFE + */ +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); + uc.uc_sigmask = td->td_proc->p_sigmask; + ret = copyout(&uc, uap->ucp, UC_COPY_SIZE); + } + return (ret); +} + +/* + * MPSAFE + */ +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_proc->p_sigmask = uc.uc_sigmask; + PROC_UNLOCK(td->td_proc); + } + } + } + return (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); + uc.uc_sigmask = td->td_proc->p_sigmask; + 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_proc->p_sigmask = uc.uc_sigmask; + PROC_UNLOCK(td->td_proc); + } + } + } + } + return (ret); +} |
