gdb/vax-bsd-nat.c

   1 /* Native-dependent code for modern VAX BSD's.
   2
   3    Copyright (C) 2004-2020 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 #include "target.h"
  26
  27 #include <sys/types.h>
  28 #include <sys/ptrace.h>
  29 #include <machine/reg.h>
  30
  31 #include "vax-tdep.h"
  32 #include "inf-ptrace.h"
  33 #include "nbsd-nat.h"
  34
  35 struct vax_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 vax_bsd_nat_target the_vax_bsd_nat_target;
  42
  43 /* Supply the general-purpose registers stored in GREGS to REGCACHE.  */
  44
  45 static void
  46 vaxbsd_supply_gregset (struct regcache *regcache, const void *gregs)
  47 {
  48   const gdb_byte *regs = (const gdb_byte *)gregs;
  49   int regnum;
  50
  51   for (regnum = 0; regnum < VAX_NUM_REGS; regnum++)
  52     regcache->raw_supply (regnum, regs + regnum * 4);
  53 }
  54
  55 /* Collect the general-purpose registers from REGCACHE and store them
  56    in GREGS.  */
  57
  58 static void
  59 vaxbsd_collect_gregset (const struct regcache *regcache,
  60                         void *gregs, int regnum)
  61 {
  62   gdb_byte *regs = (void *)gregs;
  63   int i;
  64
  65   for (i = 0; i <= VAX_NUM_REGS; i++)
  66     {
  67       if (regnum == -1 || regnum == i)
  68         regcache->raw_collect (i, regs + i * 4);
  69     }
  70 }
  71 \f
  72
  73 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
  74    for all registers.  */
  75
  76 void
  77 vax_bsd_nat_target::fetch_registers (struct regcache *regcache, int regnum)
  78 {
  79   struct reg regs;
  80   pid_t pid = regcache->ptid ().pid ();
  81   int lwp = regcache->ptid ().lwp ();
  82
  83   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
  84     perror_with_name (_("Couldn't get registers"));
  85
  86   vaxbsd_supply_gregset (regcache, &regs);
  87 }
  88
  89 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
  90    this for all registers.  */
  91
  92 void
  93 vax_bsd_nat_target::store_registers (struct regcache *regcache, int regnum)
  94 {
  95   struct reg regs;
  96   pid_t pid = regcache->ptid ().pid ();
  97   int lwp = regcache->ptid ().lwp ();
  98
  99   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
 100     perror_with_name (_("Couldn't get registers"));
 101
 102   vaxbsd_collect_gregset (regcache, &regs, regnum);
 103
 104   if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, lwp) == -1)
 105     perror_with_name (_("Couldn't write registers"));
 106 }
 107 \f
 108
 109 /* Support for debugging kernel virtual memory images.  */
 110
 111 #include <machine/pcb.h>
 112
 113 #include "bsd-kvm.h"
 114
 115 static int
 116 vaxbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 117 {
 118   int regnum;
 119
 120   /* The following is true for OpenBSD 3.5:
 121
 122      The pcb contains the register state at the context switch inside
 123      cpu_switch().  */
 124
 125   /* The stack pointer shouldn't be zero.  */
 126   if (pcb->KSP == 0)
 127     return 0;
 128
 129   for (regnum = VAX_R0_REGNUM; regnum < VAX_AP_REGNUM; regnum++)
 130     regcache->raw_supply (regnum, &pcb->R[regnum - VAX_R0_REGNUM]);
 131   regcache->raw_supply (VAX_AP_REGNUM, &pcb->AP);
 132   regcache->raw_supply (VAX_FP_REGNUM, &pcb->FP);
 133   regcache->raw_supply (VAX_SP_REGNUM, &pcb->KSP);
 134   regcache->raw_supply (VAX_PC_REGNUM, &pcb->PC);
 135   regcache->raw_supply (VAX_PS_REGNUM, &pcb->PSL);
 136
 137   return 1;
 138 }
 139
 140 void _initialize_vaxbsd_nat ();
 141 void
 142 _initialize_vaxbsd_nat ()
 143 {
 144   add_inf_child_target (&the_vax_bsd_nat_target);
 145
 146   /* Support debugging kernel virtual memory images.  */
 147   bsd_kvm_add_target (vaxbsd_supply_pcb);
 148 }