diff options
| -rw-r--r-- | lib/libc/amd64/sys/Makefile.inc | 4 | ||||
| -rw-r--r-- | lib/libc/amd64/sys/getcontext.S | 54 |
2 files changed, 56 insertions, 2 deletions
diff --git a/lib/libc/amd64/sys/Makefile.inc b/lib/libc/amd64/sys/Makefile.inc index 897ed4f7fc62..43c6c11a09f6 100644 --- a/lib/libc/amd64/sys/Makefile.inc +++ b/lib/libc/amd64/sys/Makefile.inc @@ -1,8 +1,8 @@ # from: Makefile.inc,v 1.1 1993/09/03 19:04:23 jtc Exp # $FreeBSD$ -MDASM= vfork.S brk.S cerror.S exect.S pipe.S ptrace.S reboot.S sbrk.S \ - setlogin.S sigreturn.S +MDASM= vfork.S brk.S cerror.S exect.S getcontext.S pipe.S ptrace.S \ + reboot.S sbrk.S setlogin.S sigreturn.S # Don't generate default code for these syscalls: NOASM= break.o exit.o ftruncate.o getdomainname.o getlogin.o \ diff --git a/lib/libc/amd64/sys/getcontext.S b/lib/libc/amd64/sys/getcontext.S new file mode 100644 index 000000000000..a0a77c0e4a1e --- /dev/null +++ b/lib/libc/amd64/sys/getcontext.S @@ -0,0 +1,54 @@ +/*- + * Copyright (c) 2003 Peter Wemm <peter@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 <machine/asm.h> +__FBSDID("$FreeBSD$"); + +#include <SYS.h> + +/* + * This has to be magic to handle the multiple returns. + * Otherwise, the setcontext() syscall will return here and we'll + * pop off the return address and go to the *setcontext* call. + */ + .weak _getcontext + .set _getcontext,__sys_getcontext + .weak getcontext + .set getcontext,__sys_getcontext +ENTRY(__sys_getcontext) + movq (%rsp),%rsi /* save getcontext return address */ + mov $SYS_getcontext,%rax + KERNCALL + jb 1f + addl $8,%rsp /* remove stale (setcontext) return address */ + jmp *%rsi /* restore return address */ +1: +#ifdef PIC + movq PIC_GOT(HIDENAME(cerror)),%rdx + jmp *%rdx +#else + jmp HIDENAME(cerror) +#endif |