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
  34 struct vax_bsd_nat_target final : public inf_ptrace_target
  35 {
  36   void fetch_registers (struct regcache *, int) override;
  37   void store_registers (struct regcache *, int) override;
  38 };
  39
  40 static vax_bsd_nat_target the_vax_bsd_nat_target;
  41
  42 /* Supply the general-purpose registers stored in GREGS to REGCACHE.  */
  43
  44 static void
  45 vaxbsd_supply_gregset (struct regcache *regcache, const void *gregs)
  46 {
  47   const gdb_byte *regs = gregs;
  48   int regnum;
  49
  50   for (regnum = 0; regnum < VAX_NUM_REGS; regnum++)
  51     regcache->raw_supply (regnum, regs + regnum * 4);
  52 }
  53
  54 /* Collect the general-purpose registers from REGCACHE and store them
  55    in GREGS.  */
  56
  57 static void
  58 vaxbsd_collect_gregset (const struct regcache *regcache,
  59                         void *gregs, int regnum)
  60 {
  61   gdb_byte *regs = gregs;
  62   int i;
  63
  64   for (i = 0; i <= VAX_NUM_REGS; i++)
  65     {
  66       if (regnum == -1 || regnum == i)
  67         regcache->raw_collect (i, regs + i * 4);
  68     }
  69 }
  70 \f
  71
  72 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
  73    for all registers.  */
  74
  75 void
  76 vax_bsd_nat_target::fetch_registers (struct regcache *regcache, int regnum)
  77 {
  78   struct reg regs;
  79   pid_t pid = regcache->ptid ().pid ();
  80
  81   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  82     perror_with_name (_("Couldn't get registers"));
  83
  84   vaxbsd_supply_gregset (regcache, &regs);
  85 }
  86
  87 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
  88    this for all registers.  */
  89
  90 void
  91 vax_bsd_nat_target::store_registers (struct regcache *regcache, int regnum)
  92 {
  93   struct reg regs;
  94   pid_t pid = regcache->ptid ().pid ();
  95
  96   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  97     perror_with_name (_("Couldn't get registers"));
  98
  99   vaxbsd_collect_gregset (regcache, &regs, regnum);
 100
 101   if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 102     perror_with_name (_("Couldn't write registers"));
 103 }
 104 \f
 105
 106 /* Support for debugging kernel virtual memory images.  */
 107
 108 #include <machine/pcb.h>
 109
 110 #include "bsd-kvm.h"
 111
 112 static int
 113 vaxbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 114 {
 115   int regnum;
 116
 117   /* The following is true for OpenBSD 3.5:
 118
 119      The pcb contains the register state at the context switch inside
 120      cpu_switch().  */
 121
 122   /* The stack pointer shouldn't be zero.  */
 123   if (pcb->KSP == 0)
 124     return 0;
 125
 126   for (regnum = VAX_R0_REGNUM; regnum < VAX_AP_REGNUM; regnum++)
 127     regcache->raw_supply (regnum, &pcb->R[regnum - VAX_R0_REGNUM]);
 128   regcache->raw_supply (VAX_AP_REGNUM, &pcb->AP);
 129   regcache->raw_supply (VAX_FP_REGNUM, &pcb->FP);
 130   regcache->raw_supply (VAX_SP_REGNUM, &pcb->KSP);
 131   regcache->raw_supply (VAX_PC_REGNUM, &pcb->PC);
 132   regcache->raw_supply (VAX_PS_REGNUM, &pcb->PSL);
 133
 134   return 1;
 135 }
 136
 137 void _initialize_vaxbsd_nat ();
 138 void
 139 _initialize_vaxbsd_nat ()
 140 {
 141   add_inf_child_target (&the_vax_bsd_nat_target);
 142
 143   /* Support debugging kernel virtual memory images.  */
 144   bsd_kvm_add_target (vaxbsd_supply_pcb);
 145 }