[PATCH] Revive OpenBSD/i386.

[Mark Kettenis <kettenis@chello.nl>]

This patch revives OpenBSD/i386 after it was broken by some changes to
NetBSD/i386.  There is some code duplication now, but I didn't find an
easy way to avoid it.  Since OpenBSD/i386 is indistingushable from
NetBSD/i386, it is probably not possible to build a GDB that supports
both these targets.  Fortunately we don't try to do that yet.

I'll check this in on the branch too.

Mark

Index: ChangeLog
from  Mark Kettenis  <kettenis@gnu.org>

	* configure.tgt (i[3456]86-*-openbsd*): Set gdb_target to obds.
	* config/i386/obsd.mt: New file.
	* i386bsd-nat.c (_initialize_i386bsd_nat): Introduce
	i386obsd_sc_pc_offset and i386obsd_sc_sp_offset;
	* i386obsd-nat.c (_initialize_i386obsd_nat): Set
	i386obsd_sigtramp_start and i386obsd_sigtramp_end instead of
	i386nbsd_sigtramp_start and i386nbsd_sigtramp_end.
	* i386obsd-tdep.c: New file.

Index: configure.tgt
===================================================================
RCS file: /cvs/src/src/gdb/configure.tgt,v
retrieving revision 1.86
diff -u -p -r1.86 configure.tgt
--- configure.tgt 20 Oct 2002 05:37:33 -0000 1.86
+++ configure.tgt 20 Oct 2002 11:48:54 -0000
@@ -94,7 +94,7 @@ i[3456]86-ncr-*)	gdb_target=ncr3000 ;;
 # OBSOLETE i[3456]86-*-aix*)	gdb_target=i386aix ;;
 i[3456]86-*-bsd*)	gdb_target=i386bsd ;;
 i[3456]86-*-netbsd*)	gdb_target=nbsd ;;
-i[3456]86-*-openbsd*)	gdb_target=nbsd ;;	# FIXME: needs its own target
+i[3456]86-*-openbsd*)	gdb_target=obsd ;;
 # OBSOLETE i[3456]86-*-os9k)	gdb_target=i386os9k ;;
 i[3456]86-*-go32*)	gdb_target=i386aout ;;
 i[3456]86-*-msdosdjgpp*) gdb_target=go32 ;;
Index: i386bsd-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/i386bsd-nat.c,v
retrieving revision 1.16
diff -u -p -r1.16 i386bsd-nat.c
--- i386bsd-nat.c 2 Jul 2002 09:12:37 -0000 1.16
+++ i386bsd-nat.c 20 Oct 2002 11:48:54 -0000
@@ -400,11 +400,16 @@ _initialize_i386bsd_nat (void)
   extern int i386fbsd4_sc_sp_offset;
 #define SC_PC_OFFSET i386fbsd4_sc_pc_offset
 #define SC_SP_OFFSET i386fbsd4_sc_sp_offset
-#elif defined (NetBSD) || defined (__NetBSD_Version__) || defined (OpenBSD)
+#elif defined (NetBSD) || defined (__NetBSD_Version__)
   extern int i386nbsd_sc_pc_offset;
   extern int i386nbsd_sc_sp_offset;
 #define SC_PC_OFFSET i386nbsd_sc_pc_offset
 #define SC_SP_OFFSET i386nbsd_sc_sp_offset
+#elif defined (OpenBSD)
+  extern int i386obsd_sc_pc_offset;
+  extern int i386obsd_sc_sp_offset;
+#define SC_PC_OFFSET i386obsd_sc_pc_offset
+#define SC_SP_OFFSET i386obsd_sc_sp_offset
 #else
   extern int i386bsd_sc_pc_offset;
   extern int i386bsd_sc_sp_offset;
Index: i386obsd-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/i386obsd-nat.c,v
retrieving revision 1.2
diff -u -p -r1.2 i386obsd-nat.c
--- i386obsd-nat.c 4 Jul 2002 15:17:43 -0000 1.2
+++ i386obsd-nat.c 20 Oct 2002 11:48:54 -0000
@@ -44,16 +44,16 @@ _initialize_i386obsd_nat (void)
     int mib[2];
     size_t len;
 
-    extern CORE_ADDR i386nbsd_sigtramp_start;
-    extern CORE_ADDR i386nbsd_sigtramp_end;
+    extern CORE_ADDR i386obsd_sigtramp_start;
+    extern CORE_ADDR i386obsd_sigtramp_end;
 
     mib[0] = CTL_VM;
     mib[1] = VM_PSSTRINGS;
     len = sizeof (_ps);
     if (sysctl (mib, 2, &_ps, &len, NULL, 0) == 0)
       {
-	i386nbsd_sigtramp_start = (CORE_ADDR)_ps.val - 128;
-	i386nbsd_sigtramp_end = (CORE_ADDR)_ps.val;
+	i386obsd_sigtramp_start = (CORE_ADDR)_ps.val - 128;
+	i386obsd_sigtramp_end = (CORE_ADDR)_ps.val;
       }
   }
 #endif
--- /dev/null	Sun Oct 20 13:50:02 2002
+++ config/i386/obsd.mt	Sat Oct 19 18:59:02 2002
@@ -0,0 +1,3 @@
+# Target: Intel 386 running OpenBSD
+TDEPFILES= i386-tdep.o i387-tdep.o i386bsd-tdep.o i386obsd-tdep.o corelow.o
+TM_FILE= tm-i386.h
--- /dev/null	Sun Oct 20 13:50:02 2002
+++ i386obsd-tdep.c	Sun Oct 20 13:48:37 2002
@@ -0,0 +1,122 @@
+/* Target-dependent code for OpenBSD/i386.
+   Copyright 1988, 1989, 1991, 1992, 1994, 1996, 2000, 2001, 2002
+   Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "arch-utils.h"
+#include "gdbcore.h"
+#include "regcache.h"
+
+#include "i386-tdep.h"
+#include "i387-tdep.h"
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_i386obsd_tdep (void);
+
+#define SIZEOF_STRUCT_REG	(16 * 4)
+
+static void
+i386obsd_supply_reg (char *regs, int regno)
+{
+  int i;
+
+  for (i = 0; i <= 15; i++)
+    if (regno == i || regno == -1)
+      supply_register (i, regs + i * 4);
+}
+
+static void
+fetch_core_registers (char *core_reg_sect, unsigned core_reg_size, int which,
+                      CORE_ADDR ignore)
+{
+  char *regs, *fsave;
+
+  /* We get everything from one section.  */
+  if (which != 0)
+    return;
+
+  if (core_reg_size < (SIZEOF_STRUCT_REG + 108))
+    {
+      warning ("Wrong size register set in core file.");
+      return;
+    }
+
+  regs = core_reg_sect;
+  fsave = core_reg_sect + SIZEOF_STRUCT_REG;
+
+  /* Integer registers.  */
+  i386obsd_supply_reg (regs, -1);
+
+  /* Floating point registers.  */
+  i387_supply_fsave (fsave);
+}
+
+static struct core_fns i386obsd_core_fns =
+{
+  bfd_target_unknown_flavour,		/* core_flavour */
+  default_check_format,			/* check_format */
+  default_core_sniffer,			/* core_sniffer */
+  fetch_core_registers,			/* core_read_registers */
+  NULL					/* next */
+};
+\f
+
+CORE_ADDR i386obsd_sigtramp_start = 0xbfbfdf20;
+CORE_ADDR i386obsd_sigtramp_end = 0xbfbfdff0;
+
+/* From <machine/signal.h>.  */
+int i386obsd_sc_pc_offset = 44;
+int i386obsd_sc_sp_offset = 56;
+
+static void 
+i386obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+  /* Obviously OpenBSD is BSD-based.  */
+  i386bsd_init_abi (info, gdbarch);
+
+  /* OpenBSD uses -freg-struct-return by default.  */
+  tdep->struct_return = reg_struct_return;
+
+  /* OpenBSD uses a different memory layout.  */
+  tdep->sigtramp_start = i386obsd_sigtramp_start;
+  tdep->sigtramp_end = i386obsd_sigtramp_end;
+
+  /* OpenBSD has a `struct sigcontext' that's different from the
+     origional 4.3 BSD.  */
+  tdep->sc_pc_offset = i386obsd_sc_pc_offset;
+  tdep->sc_sp_offset = i386obsd_sc_sp_offset;
+}
+
+void
+_initialize_i386obsd_tdep (void)
+{
+  add_core_fns (&i386obsd_core_fns);
+
+  /* FIXME: kettenis/20021020: Since OpenBSD/i386 binaries are
+     indistingushable from NetBSD/i386 a.out binaries, building a GDB
+     that should support both these targets will probably not work as
+     expected.  */
+#define GDB_OSABI_OPENBSD_AOUT GDB_OSABI_NETBSD_AOUT
+
+  gdbarch_register_osabi (bfd_arch_i386, GDB_OSABI_OPENBSD_AOUT,
+			  i386obsd_init_abi);
+}