gdb/alpha-bsd-nat.c

   1 /* Native-dependent code for Alpha BSD's.
   2
   3    Copyright (C) 2000-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 /* We define this to get types like register_t.  */
  21 #define _KERNTYPES
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "regcache.h"
  25
  26 #include "alpha-tdep.h"
  27 #include "alpha-bsd-tdep.h"
  28 #include "inf-ptrace.h"
  29 #include "nbsd-nat.h"
  30
  31 #include <sys/types.h>
  32 #include <sys/ptrace.h>
  33 #include <machine/reg.h>
  34
  35 struct alpha_bsd_nat_target final : public nbsd_nat_target
  36 {
  37   void fetch_registers (struct regcache *, int) override;
  38   void store_registers (struct regcache *, int) override;
  39 };
  40
  41 static alpha_bsd_nat_target the_alpha_bsd_nat_target;
  42
  43 /* Determine if PT_GETREGS fetches this register.  */
  44
  45 static int
  46 getregs_supplies (int regno)
  47 {
  48   return ((regno >= ALPHA_V0_REGNUM && regno <= ALPHA_ZERO_REGNUM)
  49           || regno >= ALPHA_PC_REGNUM);
  50 }
  51
  52 /* Fetch register REGNO from the inferior.  If REGNO is -1, do this
  53    for all registers (including the floating point registers).  */
  54
  55 void
  56 alpha_bsd_nat_target::fetch_registers (struct regcache *regcache, int regno)
  57 {
  58   if (regno == -1 || getregs_supplies (regno))
  59     {
  60       struct reg gregs;
  61
  62       if (ptrace (PT_GETREGS, regcache->ptid ().pid (),
  63                   (PTRACE_TYPE_ARG3) &gregs, 0) == -1)
  64         perror_with_name (_("Couldn't get registers"));
  65
  66       alphabsd_supply_reg (regcache, (char *) &gregs, regno);
  67       if (regno != -1)
  68         return;
  69     }
  70
  71   if (regno == -1
  72       || regno >= gdbarch_fp0_regnum (regcache->arch ()))
  73     {
  74       struct fpreg fpregs;
  75
  76       if (ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
  77                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
  78         perror_with_name (_("Couldn't get floating point status"));
  79
  80       alphabsd_supply_fpreg (regcache, (char *) &fpregs, regno);
  81     }
  82 }
  83
  84 /* Store register REGNO back into the inferior.  If REGNO is -1, do
  85    this for all registers (including the floating point registers).  */
  86
  87 void
  88 alpha_bsd_nat_target::store_registers (struct regcache *regcache, int regno)
  89 {
  90   if (regno == -1 || getregs_supplies (regno))
  91     {
  92       struct reg gregs;
  93       if (ptrace (PT_GETREGS, regcache->ptid ().pid (),
  94                   (PTRACE_TYPE_ARG3) &gregs, 0) == -1)
  95         perror_with_name (_("Couldn't get registers"));
  96
  97       alphabsd_fill_reg (regcache, (char *) &gregs, regno);
  98
  99       if (ptrace (PT_SETREGS, regcache->ptid ().pid (),
 100                   (PTRACE_TYPE_ARG3) &gregs, 0) == -1)
 101         perror_with_name (_("Couldn't write registers"));
 102
 103       if (regno != -1)
 104         return;
 105     }
 106
 107   if (regno == -1
 108       || regno >= gdbarch_fp0_regnum (regcache->arch ()))
 109     {
 110       struct fpreg fpregs;
 111
 112       if (ptrace (PT_GETFPREGS, regcache->ptid ().pid (),
 113                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 114         perror_with_name (_("Couldn't get floating point status"));
 115
 116       alphabsd_fill_fpreg (regcache, (char *) &fpregs, regno);
 117
 118       if (ptrace (PT_SETFPREGS, regcache->ptid ().pid (),
 119                   (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
 120         perror_with_name (_("Couldn't write floating point status"));
 121     }
 122 }
 123 \f
 124
 125 /* Support for debugging kernel virtual memory images.  */
 126
 127 #include <sys/signal.h>
 128 #include <machine/pcb.h>
 129
 130 #include "bsd-kvm.h"
 131
 132 static int
 133 alphabsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 134 {
 135   int regnum;
 136
 137   /* The following is true for OpenBSD 3.9:
 138
 139      The pcb contains the register state at the context switch inside
 140      cpu_switch().  */
 141
 142   /* The stack pointer shouldn't be zero.  */
 143   if (pcb->pcb_hw.apcb_ksp == 0)
 144     return 0;
 145
 146   regcache->raw_supply (ALPHA_SP_REGNUM, &pcb->pcb_hw.apcb_ksp);
 147
 148   for (regnum = ALPHA_S0_REGNUM; regnum < ALPHA_A0_REGNUM; regnum++)
 149     regcache->raw_supply (regnum, &pcb->pcb_context[regnum - ALPHA_S0_REGNUM]);
 150   regcache->raw_supply (ALPHA_RA_REGNUM, &pcb->pcb_context[7]);
 151
 152   return 1;
 153 }
 154 \f
 155
 156 void _initialize_alphabsd_nat ();
 157 void
 158 _initialize_alphabsd_nat ()
 159 {
 160   add_inf_child_target (&the_alpha_bsd_nat_target);
 161
 162   /* Support debugging kernel virtual memory images.  */
 163   bsd_kvm_add_target (alphabsd_supply_pcb);
 164 }