Line data    Source code

       1              : /* Fetch live process registers from TID.
       2              :    Copyright (C) 2026 Matt Turner
       3              :    This file is part of elfutils.
       4              : 
       5              :    This file is free software; you can redistribute it and/or modify
       6              :    it under the terms of either
       7              : 
       8              :      * the GNU Lesser General Public License as published by the Free
       9              :        Software Foundation; either version 3 of the License, or (at
      10              :        your option) any later version
      11              : 
      12              :    or
      13              : 
      14              :      * the GNU General Public License as published by the Free
      15              :        Software Foundation; either version 2 of the License, or (at
      16              :        your option) any later version
      17              : 
      18              :    or both in parallel, as here.
      19              : 
      20              :    elfutils is distributed in the hope that it will be useful, but
      21              :    WITHOUT ANY WARRANTY; without even the implied warranty of
      22              :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      23              :    General Public License for more details.
      24              : 
      25              :    You should have received copies of the GNU General Public License and
      26              :    the GNU Lesser General Public License along with this program.  If
      27              :    not, see <http://www.gnu.org/licenses/>.  */
      28              : 
      29              : 
      30              : #ifdef HAVE_CONFIG_H
      31              : # include <config.h>
      32              : #endif
      33              : 
      34              : #if defined __alpha__ && defined __linux__
      35              : # include <errno.h>
      36              : # include <stdint.h>
      37              : # include <sys/ptrace.h>
      38              : #endif
      39              : 
      40              : #define BACKEND alpha_
      41              : #include "libebl_CPU.h"
      42              : 
      43              : bool
      44            0 : alpha_set_initial_registers_tid (pid_t tid __attribute__ ((unused)),
      45              :                                  ebl_tid_registers_t *setfunc __attribute__ ((unused)),
      46              :                                  void *arg __attribute__ ((unused)))
      47              : {
      48              : #if !defined __alpha__ || !defined __linux__
      49            0 :   return false;
      50              : #else /* __alpha__ */
      51              :   /* PTRACE_PEEKUSER takes a register number: 0-31 for the integer
      52              :      registers, 32-62 for $f0-$f30, 63 for the FPCR and 64 for the PC.
      53              :      The value is the return value, so check errno rather than for -1.  */
      54              :   Dwarf_Word regs[65];
      55              :   for (int i = 0; i < 65; i++)
      56              :     {
      57              :       /* $31 and $f31 always read as zero.  */
      58              :       if (i == 31 || i == 63)
      59              :         {
      60              :           regs[i] = 0;
      61              :           continue;
      62              :         }
      63              :       errno = 0;
      64              :       regs[i] = ptrace (PTRACE_PEEKUSER, tid, (void *) (uintptr_t) i, NULL);
      65              :       if (errno != 0)
      66              :         return false;
      67              :     }
      68              : 
      69              :   /* $0-$31 and $f0-$f31, then the PC.  */
      70              :   return setfunc (0, 64, regs, arg) && setfunc (-1, 1, &regs[64], arg);
      71              : #endif /* __alpha__ */
      72              : }