| Dmitry V. Levin | d70d1c4 | 2015-03-22 22:13:55 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * PTRACE_GETREGSET was added to the kernel in v2.6.25, |
| 3 | * a PTRACE_GETREGS based fallback is provided for old kernels. |
| 4 | */ |
| 5 | static void |
| 6 | getregs_old(pid_t pid) |
| 7 | { |
| 8 | /* Use old method, with unreliable heuristical detection of 32-bitness. */ |
| 9 | get_regs_error = ptrace(PTRACE_GETREGS, pid, NULL, &x86_64_regs); |
| 10 | if (get_regs_error) |
| 11 | return; |
| 12 | |
| 13 | if (x86_64_regs.cs == 0x23) { |
| 14 | x86_io.iov_len = sizeof(i386_regs); |
| 15 | /* |
| 16 | * The order is important: i386_regs and x86_64_regs |
| 17 | * are overlaid in memory! |
| 18 | */ |
| 19 | i386_regs.ebx = x86_64_regs.rbx; |
| 20 | i386_regs.ecx = x86_64_regs.rcx; |
| 21 | i386_regs.edx = x86_64_regs.rdx; |
| 22 | i386_regs.esi = x86_64_regs.rsi; |
| 23 | i386_regs.edi = x86_64_regs.rdi; |
| 24 | i386_regs.ebp = x86_64_regs.rbp; |
| 25 | i386_regs.eax = x86_64_regs.rax; |
| 26 | /* i386_regs.xds = x86_64_regs.ds; unused by strace */ |
| 27 | /* i386_regs.xes = x86_64_regs.es; ditto... */ |
| 28 | /* i386_regs.xfs = x86_64_regs.fs; */ |
| 29 | /* i386_regs.xgs = x86_64_regs.gs; */ |
| 30 | i386_regs.orig_eax = x86_64_regs.orig_rax; |
| 31 | i386_regs.eip = x86_64_regs.rip; |
| 32 | /* i386_regs.xcs = x86_64_regs.cs; */ |
| 33 | /* i386_regs.eflags = x86_64_regs.eflags; */ |
| 34 | i386_regs.esp = x86_64_regs.rsp; |
| 35 | /* i386_regs.xss = x86_64_regs.ss; */ |
| 36 | } else { |
| 37 | x86_io.iov_len = sizeof(x86_64_regs); |
| 38 | } |
| 39 | } |