| /* |
| * Copyright (c) 2013 Denys Vlasenko <vda.linux@googlemail.com> |
| * Copyright (c) 2013-2015 Dmitry V. Levin <ldv@altlinux.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. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. |
| */ |
| |
| /* |
| * PTRACE_GETREGSET was added to the kernel in v2.6.25, |
| * a PTRACE_GETREGS based fallback is provided for old kernels. |
| */ |
| static int |
| getregs_old(pid_t pid) |
| { |
| /* Use old method, with unreliable heuristical detection of 32-bitness. */ |
| long r = ptrace(PTRACE_GETREGS, pid, NULL, &x86_64_regs); |
| if (r) |
| return r; |
| |
| if (x86_64_regs.cs == 0x23) { |
| x86_io.iov_len = sizeof(i386_regs); |
| /* |
| * The order is important: i386_regs and x86_64_regs |
| * are overlaid in memory! |
| */ |
| i386_regs.ebx = x86_64_regs.rbx; |
| i386_regs.ecx = x86_64_regs.rcx; |
| i386_regs.edx = x86_64_regs.rdx; |
| i386_regs.esi = x86_64_regs.rsi; |
| i386_regs.edi = x86_64_regs.rdi; |
| i386_regs.ebp = x86_64_regs.rbp; |
| i386_regs.eax = x86_64_regs.rax; |
| /* i386_regs.xds = x86_64_regs.ds; unused by strace */ |
| /* i386_regs.xes = x86_64_regs.es; ditto... */ |
| /* i386_regs.xfs = x86_64_regs.fs; */ |
| /* i386_regs.xgs = x86_64_regs.gs; */ |
| i386_regs.orig_eax = x86_64_regs.orig_rax; |
| i386_regs.eip = x86_64_regs.rip; |
| /* i386_regs.xcs = x86_64_regs.cs; */ |
| /* i386_regs.eflags = x86_64_regs.eflags; */ |
| i386_regs.esp = x86_64_regs.rsp; |
| /* i386_regs.xss = x86_64_regs.ss; */ |
| } else { |
| x86_io.iov_len = sizeof(x86_64_regs); |
| } |
| return 0; |
| } |