11.7Skamil/* $NetBSD: __sigtramp2.S,v 1.7 2020/10/19 11:31:01 kamil Exp $ */ 21.1Schristos 31.1Schristos/*- 41.1Schristos * Copyright (c) 2002 The NetBSD Foundation, Inc. 51.1Schristos * All rights reserved. 61.1Schristos * 71.1Schristos * This code is derived from software contributed to The NetBSD Foundation 81.1Schristos * by Christos Zoulas. 91.1Schristos * 101.1Schristos * Redistribution and use in source and binary forms, with or without 111.1Schristos * modification, are permitted provided that the following conditions 121.1Schristos * are met: 131.1Schristos * 1. Redistributions of source code must retain the above copyright 141.1Schristos * notice, this list of conditions and the following disclaimer. 151.1Schristos * 2. Redistributions in binary form must reproduce the above copyright 161.1Schristos * notice, this list of conditions and the following disclaimer in the 171.1Schristos * documentation and/or other materials provided with the distribution. 181.1Schristos * 191.1Schristos * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 201.1Schristos * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 211.1Schristos * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 221.1Schristos * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 231.1Schristos * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 241.1Schristos * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 251.1Schristos * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 261.1Schristos * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 271.1Schristos * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 281.1Schristos * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 291.1Schristos * POSSIBILITY OF SUCH DAMAGE. 301.1Schristos */ 311.1Schristos 321.1Schristos#include "SYS.h" 331.6Skamil#include "assym.h" 341.1Schristos 351.1Schristos/* 361.1Schristos * The i386 signal trampoline is invoked only to return from 371.1Schristos * the signal; the kernel calls the signal handler directly. 381.1Schristos * 391.1Schristos * On entry, stack looks like: 401.1Schristos * 411.1Schristos * ucontext structure [12+sizeof(siginfo_t)] 421.1Schristos * siginfo structure [12] 431.1Schristos * pointer to ucontext structure [8] 441.1Schristos * pointer to siginfo structure [4] 451.1Schristos * sp-> signal number [0] 461.6Skamil * 471.6Skamil * The unwind entry includes the one byte prior to the trampoline 481.6Skamil * because the unwinder will look up (return PC - 1) while unwinding. 491.6Skamil * Normally (return PC - 1) computes an address inside the call 501.6Skamil * instruction that created the child frame, but here there is no call 511.6Skamil * instruction so we have to manually add padding. 521.1Schristos */ 531.6Skamil .cfi_startproc simple 541.6Skamil .cfi_signal_frame 551.6Skamil .cfi_def_cfa esp, 140 561.6Skamil .cfi_offset eax, UC_GREGS_EAX 571.6Skamil .cfi_offset ecx, UC_GREGS_ECX 581.6Skamil .cfi_offset edx, UC_GREGS_EDX 591.6Skamil .cfi_offset ebx, UC_GREGS_EBX 601.7Skamil .cfi_offset esp, UC_GREGS_ESP 611.6Skamil .cfi_offset ebp, UC_GREGS_EBP 621.6Skamil .cfi_offset esi, UC_GREGS_ESI 631.6Skamil .cfi_offset edi, UC_GREGS_EDI 641.6Skamil .cfi_offset eip, UC_GREGS_EIP 651.6Skamil nop 661.1SchristosNENTRY(__sigtramp_siginfo_2) 671.3Sdrochner leal 12+128(%esp),%eax /* get address of ucontext */ 681.1Schristos movl %eax,4(%esp) /* put it in the argument slot */ 691.1Schristos /* fake return address already there */ 701.1Schristos SYSTRAP(setcontext) /* do setcontext */ 711.3Sdrochner movl $-1,4(%esp) /* if we return here, something is wrong */ 721.1Schristos SYSTRAP(exit) /* exit */ 731.6Skamil .cfi_endproc 741.5SuebayasiEND(__sigtramp_siginfo_2) 75