gdb/hppab-nat.c

   1 /* Machine-dependent hooks for the unix child process stratum.  This
   2    code is for the HP PA-RISC cpu.
   3
   4    Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
   5
   6    Contributed by the Center for Software Science at the
   7    University of Utah (pa-gdb-bugs@cs.utah.edu).
   8
   9 This file is part of GDB.
  10
  11 This program is free software; you can redistribute it and/or modify
  12 it under the terms of the GNU General Public License as published by
  13 the Free Software Foundation; either version 2 of the License, or
  14 (at your option) any later version.
  15
  16 This program is distributed in the hope that it will be useful,
  17 but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 GNU General Public License for more details.
  20
  21 You should have received a copy of the GNU General Public License
  22 along with this program; if not, write to the Free Software
  23 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  24
  25 #include "defs.h"
  26 #include "inferior.h"
  27 #include "target.h"
  28 #include <sys/ptrace.h>
  29
  30 /* Use an extra level of indirection for ptrace calls.
  31    This lets us breakpoint usefully on call_ptrace.   It also
  32    allows us to pass an extra argument to ptrace without
  33    using an ANSI-C specific macro.  */
  34
  35 #define ptrace call_ptrace
  36
  37 #if !defined (offsetof)
  38 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
  39 #endif
  40
  41 /* U_REGS_OFFSET is the offset of the registers within the u area.  */
  42 #if !defined (U_REGS_OFFSET)
  43 #define U_REGS_OFFSET \
  44   ptrace (PT_READ_U, inferior_pid, \
  45           (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
  46     - KERNEL_U_ADDR
  47 #endif
  48
  49 /* Fetch one register.  */
  50
  51 static void
  52 fetch_register (regno)
  53      int regno;
  54 {
  55   register unsigned int regaddr;
  56   char buf[MAX_REGISTER_RAW_SIZE];
  57   register int i;
  58
  59   /* Offset of registers within the u area.  */
  60   unsigned int offset;
  61
  62   offset = U_REGS_OFFSET;
  63
  64   regaddr = register_addr (regno, offset);
  65   for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
  66     {
  67       errno = 0;
  68       *(int *) &buf[i] = ptrace (PT_RUREGS, inferior_pid,
  69                                  (PTRACE_ARG3_TYPE) regaddr, 0);
  70       regaddr += sizeof (int);
  71       if (errno != 0)
  72         {
  73           /* Warning, not error, in case we are attached; sometimes the
  74              kernel doesn't let us at the registers.  */
  75           char *err = safe_strerror (errno);
  76           char *msg = alloca (strlen (err) + 128);
  77           sprintf (msg, "reading register %s: %s", reg_names[regno], err);
  78           warning (msg);
  79           goto error_exit;
  80         }
  81     }
  82   supply_register (regno, buf);
  83  error_exit:;
  84 }
  85
  86 /* Fetch all registers, or just one, from the child process.  */
  87
  88 void
  89 fetch_inferior_registers (regno)
  90      int regno;
  91 {
  92   if (regno == -1)
  93     for (regno = 0; regno < NUM_REGS; regno++)
  94       fetch_register (regno);
  95   else
  96     fetch_register (regno);
  97 }
  98
  99 /* Store our register values back into the inferior.
 100    If REGNO is -1, do this for all registers.
 101    Otherwise, REGNO specifies which register (so we can save time).  */
 102
 103 void
 104 store_inferior_registers (regno)
 105      int regno;
 106 {
 107   register unsigned int regaddr;
 108   extern char registers[];
 109   register int i;
 110
 111   unsigned int offset = U_REGS_OFFSET;
 112
 113   if (regno >= 0)
 114     {
 115       regaddr = register_addr (regno, offset);
 116       for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
 117         {
 118           errno = 0;
 119           ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 120                   *(int *) &registers[REGISTER_BYTE (regno) + i]);
 121           if (errno != 0)
 122             {
 123               char *err = safe_strerror (errno);
 124               char *msg = alloca (strlen (err) + 128);
 125               sprintf (msg, "writing register %s: %s", reg_names[regno], err);
 126               warning (msg);
 127             }
 128           regaddr += sizeof(int);
 129         }
 130     }
 131   else
 132     {
 133       for (regno = 0; regno < NUM_REGS; regno++)
 134         {
 135           if (CANNOT_STORE_REGISTER (regno))
 136             continue;
 137           store_inferior_registers (regno);
 138         }
 139     }
 140   return;
 141 }
 142