| 1 | /* Native-dependent code for NetBSD/i386. |
| 2 | |
| 3 | Copyright (C) 2004-2017 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 "gdbcore.h" |
| 22 | #include "regcache.h" |
| 23 | #include "target.h" |
| 24 | |
| 25 | #include "i386-tdep.h" |
| 26 | #include "i386-bsd-nat.h" |
| 27 | |
| 28 | /* Support for debugging kernel virtual memory images. */ |
| 29 | |
| 30 | #include <sys/types.h> |
| 31 | #include <machine/frame.h> |
| 32 | #include <machine/pcb.h> |
| 33 | |
| 34 | #include "nbsd-nat.h" |
| 35 | #include "bsd-kvm.h" |
| 36 | |
| 37 | static int |
| 38 | i386nbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) |
| 39 | { |
| 40 | struct switchframe sf; |
| 41 | |
| 42 | /* The following is true for NetBSD 1.6.2: |
| 43 | |
| 44 | The pcb contains %esp and %ebp at the point of the context switch |
| 45 | in cpu_switch(). At that point we have a stack frame as |
| 46 | described by `struct switchframe', which for NetBSD 1.6.2 has the |
| 47 | following layout: |
| 48 | |
| 49 | interrupt level |
| 50 | %edi |
| 51 | %esi |
| 52 | %ebx |
| 53 | %eip |
| 54 | |
| 55 | we reconstruct the register state as it would look when we just |
| 56 | returned from cpu_switch(). */ |
| 57 | |
| 58 | /* The stack pointer shouldn't be zero. */ |
| 59 | if (pcb->pcb_esp == 0) |
| 60 | return 0; |
| 61 | |
| 62 | read_memory (pcb->pcb_esp, (gdb_byte *)&sf, sizeof sf); |
| 63 | pcb->pcb_esp += sizeof (struct switchframe); |
| 64 | regcache_raw_supply (regcache, I386_EDI_REGNUM, &sf.sf_edi); |
| 65 | regcache_raw_supply (regcache, I386_ESI_REGNUM, &sf.sf_esi); |
| 66 | regcache_raw_supply (regcache, I386_EBP_REGNUM, &pcb->pcb_ebp); |
| 67 | regcache_raw_supply (regcache, I386_ESP_REGNUM, &pcb->pcb_esp); |
| 68 | regcache_raw_supply (regcache, I386_EBX_REGNUM, &sf.sf_ebx); |
| 69 | regcache_raw_supply (regcache, I386_EIP_REGNUM, &sf.sf_eip); |
| 70 | |
| 71 | return 1; |
| 72 | } |
| 73 | |
| 74 | void |
| 75 | _initialize_i386nbsd_nat (void) |
| 76 | { |
| 77 | struct target_ops *t; |
| 78 | |
| 79 | /* Add some extra features to the common *BSD/i386 target. */ |
| 80 | t = i386bsd_target (); |
| 81 | t->to_pid_to_exec_file = nbsd_pid_to_exec_file; |
| 82 | add_target (t); |
| 83 | |
| 84 | /* Support debugging kernel virtual memory images. */ |
| 85 | bsd_kvm_add_target (i386nbsd_supply_pcb); |
| 86 | } |