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 #include "defs.h"
  21 #include "inferior.h"
  22 #include "regcache.h"
  23 #include "target.h"
  24
  25 #include <sys/types.h>
  26 #include <sys/ptrace.h>
  27 #include <machine/reg.h>
  28
  29 #include "vax-tdep.h"
  30 #include "inf-ptrace.h"
  31
  32 struct vax_bsd_nat_target final : public inf_ptrace_target
  33 {
  34   void fetch_registers (struct regcache *, int) override;
  35   void store_registers (struct regcache *, int) override;
  36 };
  37
  38 static vax_bsd_nat_target the_vax_bsd_nat_target;
  39
  40 /* Supply the general-purpose registers stored in GREGS to REGCACHE.  */
  41
  42 static void
  43 vaxbsd_supply_gregset (struct regcache *regcache, const void *gregs)
  44 {
  45   const gdb_byte *regs = gregs;
  46   int regnum;
  47
  48   for (regnum = 0; regnum < VAX_NUM_REGS; regnum++)
  49     regcache->raw_supply (regnum, regs + regnum * 4);
  50 }
  51
  52 /* Collect the general-purpose registers from REGCACHE and store them
  53    in GREGS.  */
  54
  55 static void
  56 vaxbsd_collect_gregset (const struct regcache *regcache,
  57                         void *gregs, int regnum)
  58 {
  59   gdb_byte *regs = gregs;
  60   int i;
  61
  62   for (i = 0; i <= VAX_NUM_REGS; i++)
  63     {
  64       if (regnum == -1 || regnum == i)
  65         regcache->raw_collect (i, regs + i * 4);
  66     }
  67 }
  68 \f
  69
  70 /* Fetch register REGNUM from the inferior.  If REGNUM is -1, do this
  71    for all registers.  */
  72
  73 void
  74 vax_bsd_nat_target::fetch_registers (struct regcache *regcache, int regnum)
  75 {
  76   struct reg regs;
  77   pid_t pid = regcache->ptid ().pid ();
  78
  79   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  80     perror_with_name (_("Couldn't get registers"));
  81
  82   vaxbsd_supply_gregset (regcache, &regs);
  83 }
  84
  85 /* Store register REGNUM back into the inferior.  If REGNUM is -1, do
  86    this for all registers.  */
  87
  88 void
  89 vax_bsd_nat_target::store_registers (struct regcache *regcache, int regnum)
  90 {
  91   struct reg regs;
  92   pid_t pid = regcache->ptid ().pid ();
  93
  94   if (ptrace (PT_GETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
  95     perror_with_name (_("Couldn't get registers"));
  96
  97   vaxbsd_collect_gregset (regcache, &regs, regnum);
  98
  99   if (ptrace (PT_SETREGS, pid, (PTRACE_TYPE_ARG3) &regs, 0) == -1)
 100     perror_with_name (_("Couldn't write registers"));
 101 }
 102 \f
 103
 104 /* Support for debugging kernel virtual memory images.  */
 105
 106 #include <machine/pcb.h>
 107
 108 #include "bsd-kvm.h"
 109
 110 static int
 111 vaxbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
 112 {
 113   int regnum;
 114
 115   /* The following is true for OpenBSD 3.5:
 116
 117      The pcb contains the register state at the context switch inside
 118      cpu_switch().  */
 119
 120   /* The stack pointer shouldn't be zero.  */
 121   if (pcb->KSP == 0)
 122     return 0;
 123
 124   for (regnum = VAX_R0_REGNUM; regnum < VAX_AP_REGNUM; regnum++)
 125     regcache->raw_supply (regnum, &pcb->R[regnum - VAX_R0_REGNUM]);
 126   regcache->raw_supply (VAX_AP_REGNUM, &pcb->AP);
 127   regcache->raw_supply (VAX_FP_REGNUM, &pcb->FP);
 128   regcache->raw_supply (VAX_SP_REGNUM, &pcb->KSP);
 129   regcache->raw_supply (VAX_PC_REGNUM, &pcb->PC);
 130   regcache->raw_supply (VAX_PS_REGNUM, &pcb->PSL);
 131
 132   return 1;
 133 }
 134
 135 void
 136 _initialize_vaxbsd_nat (void)
 137 {
 138   add_inf_child_target (&the_vax_bsd_nat_target);
 139
 140   /* Support debugging kernel virtual memory images.  */
 141   bsd_kvm_add_target (vaxbsd_supply_pcb);
 142 }