cosmopolitan/libc/calls/sigenter.S

55 lines
2.6 KiB
ArmAsm

/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
vi: set et ft=asm ts=8 tw=8 fenc=utf-8 :vi
Copyright 2020 Justine Alexandra Roberts Tunney
This program is free software; you can redistribute it and/or modify │
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License. │
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of │
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software │
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
#include "libc/calls/internal.h"
#include "libc/macros.h"
.source __FILE__
/ System Five signal handler.
/
/ This is needed because (1) a signal is allowed to trigger at
/ just about any time, and leaf functions (e.g. memcpy) aren't
/ required to leave Cosmopolitan's image base register alone.
/
/ @param %edi is the signal number
/ @param %rsi will be passed for sigactions
/ @param %rdx will be passed for sigactions
/ @return true if handler was invoked
__sigenter:
push %rbp
mov %rsp,%rbp
push %rbx
push %rbx
ezlea _base,bx
.profilable
ezlea g_sighandrvas,ax
and $NSIG-1,%edi
mov (%rax,%rdi,4),%eax
cmp $kSigactionMinRva,%eax
jl 2f
add %rbx,%rax
call *%rax
mov $1,%eax
1: pop %rbx
leave
ret
2: xor %eax,%eax
jmp 1b
.endfn __sigenter,globl,hidden