gdb/coredep.c

   1 /* Extract registers from a "standard" core file, for GDB.
   2    Copyright (C) 1988-1991  Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /* core.c is supposed to be the more machine-independent aspects of this;
  21    this file is more machine-specific.  */
  22
  23 #include "defs.h"
  24 #include <sys/types.h>
  25 #include <sys/param.h>
  26 #include "gdbcore.h"
  27
  28 /* These are needed on various systems to expand REGISTER_U_ADDR.  */
  29 #ifndef USG
  30 #include <sys/dir.h>
  31 #include <sys/file.h>
  32 #include <sys/stat.h>
  33 #include <sys/user.h>
  34 #include <sys/ptrace.h>
  35 #endif
  36
  37 /* Extract the register values out of the core file and store
  38    them where `read_register' will find them.
  39
  40    CORE_REG_SECT points to the register values themselves, read into memory.
  41    CORE_REG_SIZE is the size of that area.
  42    WHICH says which set of registers we are handling (0 = int, 2 = float
  43          on machines where they are discontiguous).
  44    REG_ADDR is the offset from u.u_ar0 to the register values relative to
  45             core_reg_sect.  This is used with old-fashioned core files to
  46             locate the registers in a large upage-plus-stack ".reg" section.
  47             Original upage address X is at location core_reg_sect+x+reg_addr.
  48  */
  49
  50 void
  51 fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
  52      char *core_reg_sect;
  53      unsigned core_reg_size;
  54      int which;
  55      unsigned reg_addr;
  56 {
  57   register int regno;
  58   register unsigned int addr;
  59   int bad_reg = -1;
  60   register reg_ptr = -reg_addr;         /* Original u.u_ar0 is -reg_addr. */
  61
  62   /* If u.u_ar0 was an absolute address in the core file, relativize it now,
  63      so we can use it as an offset into core_reg_sect.  When we're done,
  64      "register 0" will be at core_reg_sect+reg_ptr, and we can use
  65      register_addr to offset to the other registers.  If this is a modern
  66      core file without a upage, reg_ptr will be zero and this is all a big
  67      NOP.  */
  68   if (reg_ptr > core_reg_size)
  69     reg_ptr -= KERNEL_U_ADDR;
  70
  71   for (regno = 0; regno < NUM_REGS; regno++)
  72     {
  73       addr = register_addr (regno, reg_ptr);
  74       if (addr >= core_reg_size) {
  75         if (bad_reg < 0)
  76           bad_reg = regno;
  77       } else {
  78         supply_register (regno, core_reg_sect + addr);
  79       }
  80     }
  81   if (bad_reg >= 0)
  82     {
  83       error ("Register %s not found in core file.", reg_names[bad_reg]);
  84     }
  85 }
  86
  87
  88 #ifdef REGISTER_U_ADDR
  89
  90 /* Return the address in the core dump or inferior of register REGNO.
  91    BLOCKEND is the address of the end of the user structure.  */
  92
  93 unsigned int
  94 register_addr (regno, blockend)
  95      int regno;
  96      int blockend;
  97 {
  98   int addr;
  99
 100   if (regno < 0 || regno >= NUM_REGS)
 101     error ("Invalid register number %d.", regno);
 102
 103   REGISTER_U_ADDR (addr, blockend, regno);
 104
 105   return addr;
 106 }
 107
 108 #endif /* REGISTER_U_ADDR */