Initial revision

1 files changed, 837 insertions, 0 deletions

diff --git a/gdb/lynx-nat.c b/gdb/lynx-nat.c
new file mode 100644
index 00000000000..f006aa46c9c
--- /dev/null
+++ b/gdb/lynx-nat.c
@@ -0,0 +1,837 @@
+/* Native-dependent code for LynxOS.
+   Copyright 1993, 1994 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 "frame.h"
+#include "inferior.h"
+#include "target.h"
+#include "gdbcore.h"
+
+#include <sys/ptrace.h>
+#include <sys/wait.h>
+#include <sys/fpp.h>
+
+static unsigned long registers_addr PARAMS ((int pid));
+static void fetch_core_registers PARAMS ((char *, unsigned, int, CORE_ADDR);
+
+#define X(ENTRY)(offsetof(struct econtext, ENTRY))
+
+#ifdef I386
+/* Mappings from tm-i386v.h */
+
+static int regmap[] =
+{
+  X(eax),
+  X(ecx),
+  X(edx),
+  X(ebx),
+  X(esp),			/* sp */
+  X(ebp),			/* fp */
+  X(esi),
+  X(edi),
+  X(eip),			/* pc */
+  X(flags),			/* ps */
+  X(cs),
+  X(ss),
+  X(ds),
+  X(es),
+  X(ecode),			/* Lynx doesn't give us either fs or gs, so */
+  X(fault),			/* we just substitute these two in the hopes
+				   that they are useful. */
+};
+#endif /* I386 */
+
+#ifdef M68K
+/* Mappings from tm-m68k.h */
+
+static int regmap[] =
+{
+  X(regs[0]),			/* d0 */
+  X(regs[1]),			/* d1 */
+  X(regs[2]),			/* d2 */
+  X(regs[3]),			/* d3 */
+  X(regs[4]),			/* d4 */
+  X(regs[5]),			/* d5 */
+  X(regs[6]),			/* d6 */
+  X(regs[7]),			/* d7 */
+  X(regs[8]),			/* a0 */
+  X(regs[9]),			/* a1 */
+  X(regs[10]),			/* a2 */
+  X(regs[11]),			/* a3 */
+  X(regs[12]),			/* a4 */
+  X(regs[13]),			/* a5 */
+  X(regs[14]),			/* fp */
+  offsetof (st_t, usp) - offsetof (st_t, ec), /* sp */
+  X(status),			/* ps */
+  X(pc),
+
+  X(fregs[0*3]),		/* fp0 */
+  X(fregs[1*3]),		/* fp1 */
+  X(fregs[2*3]),		/* fp2 */
+  X(fregs[3*3]),		/* fp3 */
+  X(fregs[4*3]),		/* fp4 */
+  X(fregs[5*3]),		/* fp5 */
+  X(fregs[6*3]),		/* fp6 */
+  X(fregs[7*3]),		/* fp7 */
+
+  X(fcregs[0]),			/* fpcontrol */
+  X(fcregs[1]),			/* fpstatus */
+  X(fcregs[2]),			/* fpiaddr */
+  X(ssw),			/* fpcode */
+  X(fault),			/* fpflags */
+};
+#endif /* M68K */
+
+#ifdef SPARC
+/* Mappings from tm-sparc.h */
+
+#define FX(ENTRY)(offsetof(struct fcontext, ENTRY))
+
+static int regmap[] =
+{
+  -1,				/* g0 */
+  X(g1),
+  X(g2),
+  X(g3),
+  X(g4),
+  -1,				/* g5->g7 aren't saved by Lynx */
+  -1,
+  -1,
+
+  X(o[0]),
+  X(o[1]),
+  X(o[2]),
+  X(o[3]),
+  X(o[4]),
+  X(o[5]),
+  X(o[6]),			/* sp */
+  X(o[7]),			/* ra */
+
+  -1,-1,-1,-1,-1,-1,-1,-1,	/* l0 -> l7 */
+
+  -1,-1,-1,-1,-1,-1,-1,-1,	/* i0 -> i7 */
+
+  FX(f.fregs[0]),		/* f0 */
+  FX(f.fregs[1]),
+  FX(f.fregs[2]),
+  FX(f.fregs[3]),
+  FX(f.fregs[4]),
+  FX(f.fregs[5]),
+  FX(f.fregs[6]),
+  FX(f.fregs[7]),
+  FX(f.fregs[8]),
+  FX(f.fregs[9]),
+  FX(f.fregs[10]),
+  FX(f.fregs[11]),
+  FX(f.fregs[12]),
+  FX(f.fregs[13]),
+  FX(f.fregs[14]),
+  FX(f.fregs[15]),
+  FX(f.fregs[16]),
+  FX(f.fregs[17]),
+  FX(f.fregs[18]),
+  FX(f.fregs[19]),
+  FX(f.fregs[20]),
+  FX(f.fregs[21]),
+  FX(f.fregs[22]),
+  FX(f.fregs[23]),
+  FX(f.fregs[24]),
+  FX(f.fregs[25]),
+  FX(f.fregs[26]),
+  FX(f.fregs[27]),
+  FX(f.fregs[28]),
+  FX(f.fregs[29]),
+  FX(f.fregs[30]),
+  FX(f.fregs[31]),
+
+  X(y),
+  X(psr),
+  X(wim),
+  X(tbr),
+  X(pc),
+  X(npc),
+  FX(fsr),			/* fpsr */
+  -1,				/* cpsr */
+};
+#endif /* SPARC */
+
+#ifdef rs6000
+
+static int regmap[] =
+{
+  X(iregs[0]),			/* r0 */
+  X(iregs[1]),
+  X(iregs[2]),
+  X(iregs[3]),
+  X(iregs[4]),
+  X(iregs[5]),
+  X(iregs[6]),
+  X(iregs[7]),
+  X(iregs[8]),
+  X(iregs[9]),
+  X(iregs[10]),
+  X(iregs[11]),
+  X(iregs[12]),
+  X(iregs[13]),
+  X(iregs[14]),
+  X(iregs[15]),
+  X(iregs[16]),
+  X(iregs[17]),
+  X(iregs[18]),
+  X(iregs[19]),
+  X(iregs[20]),
+  X(iregs[21]),
+  X(iregs[22]),
+  X(iregs[23]),
+  X(iregs[24]),
+  X(iregs[25]),
+  X(iregs[26]),
+  X(iregs[27]),
+  X(iregs[28]),
+  X(iregs[29]),
+  X(iregs[30]),
+  X(iregs[31]),
+
+  X(fregs[0]),			/* f0 */
+  X(fregs[1]),
+  X(fregs[2]),
+  X(fregs[3]),
+  X(fregs[4]),
+  X(fregs[5]),
+  X(fregs[6]),
+  X(fregs[7]),
+  X(fregs[8]),
+  X(fregs[9]),
+  X(fregs[10]),
+  X(fregs[11]),
+  X(fregs[12]),
+  X(fregs[13]),
+  X(fregs[14]),
+  X(fregs[15]),
+  X(fregs[16]),
+  X(fregs[17]),
+  X(fregs[18]),
+  X(fregs[19]),
+  X(fregs[20]),
+  X(fregs[21]),
+  X(fregs[22]),
+  X(fregs[23]),
+  X(fregs[24]),
+  X(fregs[25]),
+  X(fregs[26]),
+  X(fregs[27]),
+  X(fregs[28]),
+  X(fregs[29]),
+  X(fregs[30]),
+  X(fregs[31]),
+
+  X(srr0),			/* IAR (PC) */
+  X(srr1),			/* MSR (PS) */
+  X(cr),			/* CR */
+  X(lr),			/* LR */
+  X(ctr),			/* CTR */
+  X(xer),			/* XER */
+  X(mq)				/* MQ */
+};
+
+#endif /* rs6000 */
+
+#ifdef SPARC
+
+/* This routine handles some oddball cases for Sparc registers and LynxOS.
+   In partucular, it causes refs to G0, g5->7, and all fp regs to return zero.
+   It also handles knows where to find the I & L regs on the stack.  */
+
+void
+fetch_inferior_registers (regno)
+     int regno;
+{
+  int whatregs = 0;
+
+#define WHATREGS_FLOAT 1
+#define WHATREGS_GEN 2
+#define WHATREGS_STACK 4
+
+  if (regno == -1)
+    whatregs = WHATREGS_FLOAT | WHATREGS_GEN | WHATREGS_STACK;
+  else if (regno >= L0_REGNUM && regno <= I7_REGNUM)
+    whatregs = WHATREGS_STACK;
+  else if (regno >= FP0_REGNUM && regno < FP0_REGNUM + 32)
+    whatregs = WHATREGS_FLOAT;
+  else
+    whatregs = WHATREGS_GEN;
+
+  if (whatregs & WHATREGS_GEN)
+    {
+      struct econtext ec;		/* general regs */
+      char buf[MAX_REGISTER_RAW_SIZE];
+      int retval;
+      int i;
+
+      errno = 0;
+      retval = ptrace (PTRACE_GETREGS, inferior_pid, (PTRACE_ARG3_TYPE) &ec,
+		       0);
+      if (errno)
+	perror_with_name ("ptrace(PTRACE_GETREGS)");
+  
+      memset (buf, 0, REGISTER_RAW_SIZE (G0_REGNUM));
+      supply_register (G0_REGNUM, buf);
+      supply_register (TBR_REGNUM, (char *)&ec.tbr);
+
+      memcpy (&registers[REGISTER_BYTE (G1_REGNUM)], &ec.g1,
+	      4 * REGISTER_RAW_SIZE (G1_REGNUM));
+      for (i = G1_REGNUM; i <= G1_REGNUM + 3; i++)
+	register_valid[i] = 1;
+
+      supply_register (PS_REGNUM, (char *)&ec.psr);
+      supply_register (Y_REGNUM, (char *)&ec.y);
+      supply_register (PC_REGNUM, (char *)&ec.pc);
+      supply_register (NPC_REGNUM, (char *)&ec.npc);
+      supply_register (WIM_REGNUM, (char *)&ec.wim);
+
+      memcpy (&registers[REGISTER_BYTE (O0_REGNUM)], ec.o,
+	      8 * REGISTER_RAW_SIZE (O0_REGNUM));
+      for (i = O0_REGNUM; i <= O0_REGNUM + 7; i++)
+	register_valid[i] = 1;
+    }
+
+  if (whatregs & WHATREGS_STACK)
+    {
+      CORE_ADDR sp;
+      int i;
+
+      sp = read_register (SP_REGNUM);
+
+      target_xfer_memory (sp + FRAME_SAVED_I0,
+			  &registers[REGISTER_BYTE(I0_REGNUM)],
+			  8 * REGISTER_RAW_SIZE (I0_REGNUM), 0);
+      for (i = I0_REGNUM; i <= I7_REGNUM; i++)
+	register_valid[i] = 1;
+
+      target_xfer_memory (sp + FRAME_SAVED_L0,
+			  &registers[REGISTER_BYTE(L0_REGNUM)],
+			  8 * REGISTER_RAW_SIZE (L0_REGNUM), 0);
+      for (i = L0_REGNUM; i <= L0_REGNUM + 7; i++)
+	register_valid[i] = 1;
+    }
+
+  if (whatregs & WHATREGS_FLOAT)
+    {
+      struct fcontext fc;		/* fp regs */
+      int retval;
+      int i;
+
+      errno = 0;
+      retval = ptrace (PTRACE_GETFPREGS, inferior_pid, (PTRACE_ARG3_TYPE) &fc,
+		       0);
+      if (errno)
+	perror_with_name ("ptrace(PTRACE_GETFPREGS)");
+  
+      memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], fc.f.fregs,
+	      32 * REGISTER_RAW_SIZE (FP0_REGNUM));
+      for (i = FP0_REGNUM; i <= FP0_REGNUM + 31; i++)
+	register_valid[i] = 1;
+
+      supply_register (FPS_REGNUM, (char *)&fc.fsr);
+    }
+}
+
+/* This routine handles storing of the I & L regs for the Sparc.  The trick
+   here is that they actually live on the stack.  The really tricky part is
+   that when changing the stack pointer, the I & L regs must be written to
+   where the new SP points, otherwise the regs will be incorrect when the
+   process is started up again.   We assume that the I & L regs are valid at
+   this point.  */
+
+void
+store_inferior_registers (regno)
+     int regno;
+{
+  int whatregs = 0;
+
+  if (regno == -1)
+    whatregs = WHATREGS_FLOAT | WHATREGS_GEN | WHATREGS_STACK;
+  else if (regno >= L0_REGNUM && regno <= I7_REGNUM)
+    whatregs = WHATREGS_STACK;
+  else if (regno >= FP0_REGNUM && regno < FP0_REGNUM + 32)
+    whatregs = WHATREGS_FLOAT;
+  else if (regno == SP_REGNUM)
+    whatregs = WHATREGS_STACK | WHATREGS_GEN;
+  else
+    whatregs = WHATREGS_GEN;
+
+  if (whatregs & WHATREGS_GEN)
+    {
+      struct econtext ec;		/* general regs */
+      int retval;
+
+      ec.tbr = read_register (TBR_REGNUM);
+      memcpy (&ec.g1, &registers[REGISTER_BYTE (G1_REGNUM)],
+	      4 * REGISTER_RAW_SIZE (G1_REGNUM));
+
+      ec.psr = read_register (PS_REGNUM);
+      ec.y = read_register (Y_REGNUM);
+      ec.pc = read_register (PC_REGNUM);
+      ec.npc = read_register (NPC_REGNUM);
+      ec.wim = read_register (WIM_REGNUM);
+
+      memcpy (ec.o, &registers[REGISTER_BYTE (O0_REGNUM)],
+	      8 * REGISTER_RAW_SIZE (O0_REGNUM));
+
+      errno = 0;
+      retval = ptrace (PTRACE_SETREGS, inferior_pid, (PTRACE_ARG3_TYPE) &ec,
+		       0);
+      if (errno)
+	perror_with_name ("ptrace(PTRACE_SETREGS)");
+    }
+
+  if (whatregs & WHATREGS_STACK)
+    {
+      int regoffset;
+      CORE_ADDR sp;
+
+      sp = read_register (SP_REGNUM);
+
+      if (regno == -1 || regno == SP_REGNUM)
+	{
+	  if (!register_valid[L0_REGNUM+5])
+	    abort();
+	  target_xfer_memory (sp + FRAME_SAVED_I0,
+			      &registers[REGISTER_BYTE (I0_REGNUM)],
+			      8 * REGISTER_RAW_SIZE (I0_REGNUM), 1);
+
+	  target_xfer_memory (sp + FRAME_SAVED_L0,
+			      &registers[REGISTER_BYTE (L0_REGNUM)],
+			      8 * REGISTER_RAW_SIZE (L0_REGNUM), 1);
+	}
+      else if (regno >= L0_REGNUM && regno <= I7_REGNUM)
+	{
+	  if (!register_valid[regno])
+	    abort();
+	  if (regno >= L0_REGNUM && regno <= L0_REGNUM + 7)
+	    regoffset = REGISTER_BYTE (regno) - REGISTER_BYTE (L0_REGNUM)
+	      + FRAME_SAVED_L0;
+	  else
+	    regoffset = REGISTER_BYTE (regno) - REGISTER_BYTE (I0_REGNUM)
+	      + FRAME_SAVED_I0;
+	  target_xfer_memory (sp + regoffset, &registers[REGISTER_BYTE (regno)],
+			      REGISTER_RAW_SIZE (regno), 1);
+	}
+    }
+
+  if (whatregs & WHATREGS_FLOAT)
+    {
+      struct fcontext fc;		/* fp regs */
+      int retval;
+
+/* We read fcontext first so that we can get good values for fq_t... */
+      errno = 0;
+      retval = ptrace (PTRACE_GETFPREGS, inferior_pid, (PTRACE_ARG3_TYPE) &fc,
+		       0);
+      if (errno)
+	perror_with_name ("ptrace(PTRACE_GETFPREGS)");
+  
+      memcpy (fc.f.fregs, &registers[REGISTER_BYTE (FP0_REGNUM)],
+	      32 * REGISTER_RAW_SIZE (FP0_REGNUM));
+
+      fc.fsr = read_register (FPS_REGNUM);
+
+      errno = 0;
+      retval = ptrace (PTRACE_SETFPREGS, inferior_pid, (PTRACE_ARG3_TYPE) &fc,
+		       0);
+      if (errno)
+	perror_with_name ("ptrace(PTRACE_SETFPREGS)");
+      }
+}
+#endif /* SPARC */
+
+#if defined (I386) || defined (M68K) || defined (rs6000)
+
+/* Return the offset relative to the start of the per-thread data to the
+   saved context block.  */
+
+static unsigned long
+registers_addr(pid)
+     int pid;
+{
+  CORE_ADDR stblock;
+  int ecpoff = offsetof(st_t, ecp);
+  CORE_ADDR ecp;
+
+  errno = 0;
+  stblock = (CORE_ADDR) ptrace (PTRACE_THREADUSER, pid, (PTRACE_ARG3_TYPE)0,
+				0);
+  if (errno)
+    perror_with_name ("ptrace(PTRACE_THREADUSER)");
+
+  ecp = (CORE_ADDR) ptrace (PTRACE_PEEKTHREAD, pid, (PTRACE_ARG3_TYPE)ecpoff,
+			    0);
+  if (errno)
+    perror_with_name ("ptrace(PTRACE_PEEKTHREAD)");
+
+  return ecp - stblock;
+}
+
+/* Fetch one or more registers from the inferior.  REGNO == -1 to get
+   them all.  We actually fetch more than requested, when convenient,
+   marking them as valid so we won't fetch them again.  */
+
+void
+fetch_inferior_registers (regno)
+     int regno;
+{
+  int reglo, reghi;
+  int i;
+  unsigned long ecp;
+
+  if (regno == -1)
+    {
+      reglo = 0;
+      reghi = NUM_REGS - 1;
+    }
+  else
+    reglo = reghi = regno;
+
+  ecp = registers_addr (inferior_pid);
+
+  for (regno = reglo; regno <= reghi; regno++)
+    {
+      char buf[MAX_REGISTER_RAW_SIZE];
+      int ptrace_fun = PTRACE_PEEKTHREAD;
+
+#ifdef M68K
+      ptrace_fun = regno == SP_REGNUM ? PTRACE_PEEKUSP : PTRACE_PEEKTHREAD;
+#endif
+
+      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
+	{
+	  unsigned int reg;
+
+	  errno = 0;
+	  reg = ptrace (ptrace_fun, inferior_pid,
+			(PTRACE_ARG3_TYPE) (ecp + regmap[regno] + i), 0);
+	  if (errno)
+	    perror_with_name ("ptrace(PTRACE_PEEKUSP)");
+  
+	  *(int *)&buf[i] = reg;
+	}
+      supply_register (regno, buf);
+    }
+}
+
+/* Store our register values back into the inferior.
+   If REGNO is -1, do this for all registers.
+   Otherwise, REGNO specifies which register (so we can save time).  */
+
+/* Registers we shouldn't try to store.  */
+#if !defined (CANNOT_STORE_REGISTER)
+#define CANNOT_STORE_REGISTER(regno) 0
+#endif
+
+void
+store_inferior_registers (regno)
+     int regno;
+{
+  int reglo, reghi;
+  int i;
+  unsigned long ecp;
+
+  if (regno == -1)
+    {
+      reglo = 0;
+      reghi = NUM_REGS - 1;
+    }
+  else
+    reglo = reghi = regno;
+
+  ecp = registers_addr (inferior_pid);
+
+  for (regno = reglo; regno <= reghi; regno++)
+    {
+      int ptrace_fun = PTRACE_POKEUSER;
+
+      if (CANNOT_STORE_REGISTER (regno))
+	continue;
+
+#ifdef M68K
+      ptrace_fun = regno == SP_REGNUM ? PTRACE_POKEUSP : PTRACE_POKEUSER;
+#endif
+
+      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
+	{
+	  unsigned int reg;
+
+	  reg = *(unsigned int *)&registers[REGISTER_BYTE (regno) + i];
+
+	  errno = 0;
+	  ptrace (ptrace_fun, inferior_pid,
+		  (PTRACE_ARG3_TYPE) (ecp + regmap[regno] + i), reg);
+	  if (errno)
+	    perror_with_name ("ptrace(PTRACE_POKEUSP)");
+	}
+    }
+}
+#endif /* defined (I386) || defined (M68K) || defined (rs6000) */
+
+/* Wait for child to do something.  Return pid of child, or -1 in case
+   of error; store status through argument pointer OURSTATUS.  */
+
+int
+child_wait (pid, ourstatus)
+     int pid;
+     struct target_waitstatus *ourstatus;
+{
+  int save_errno;
+  int thread;
+  union wait status;
+
+  while (1)
+    {
+      int sig;
+
+      set_sigint_trap();	/* Causes SIGINT to be passed on to the
+				   attached process. */
+      pid = wait (&status);
+
+      save_errno = errno;
+
+      clear_sigint_trap();
+
+      if (pid == -1)
+	{
+	  if (save_errno == EINTR)
+	    continue;
+	  fprintf_unfiltered (gdb_stderr, "Child process unexpectedly missing: %s.\n",
+		   safe_strerror (save_errno));
+	  /* Claim it exited with unknown signal.  */
+	  ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
+	  ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
+	  return -1;
+	}
+
+      if (pid != PIDGET (inferior_pid))	/* Some other process?!? */
+	continue;
+
+      thread = status.w_tid;	/* Get thread id from status */
+
+      /* Initial thread value can only be acquired via wait, so we have to
+	 resort to this hack.  */
+
+      if (TIDGET (inferior_pid) == 0 && thread != 0)
+	{
+	  inferior_pid = BUILDPID (inferior_pid, thread);
+	  add_thread (inferior_pid);
+	}
+
+      pid = BUILDPID (pid, thread);
+
+      /* We've become a single threaded process again.  */
+      if (thread == 0)
+	inferior_pid = pid;
+
+      /* Check for thread creation.  */
+      if (WIFSTOPPED(status)
+	  && WSTOPSIG(status) == SIGTRAP
+	  && !in_thread_list (pid))
+	{
+	  int realsig;
+
+	  realsig = ptrace (PTRACE_GETTRACESIG, pid, (PTRACE_ARG3_TYPE)0, 0);
+
+	  if (realsig == SIGNEWTHREAD)
+	    {
+	      /* It's a new thread notification.  We don't want to much with
+		 realsig -- the code in wait_for_inferior expects SIGTRAP. */
+	      ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
+	      ourstatus->value.sig = TARGET_SIGNAL_0;
+	      return pid;
+	    }
+	  else
+	    error ("Signal for unknown thread was not SIGNEWTHREAD");
+	}
+
+      /* Check for thread termination.  */
+      else if (WIFSTOPPED(status)
+	       && WSTOPSIG(status) == SIGTRAP
+	       && in_thread_list (pid))
+	{
+	  int realsig;
+
+	  realsig = ptrace (PTRACE_GETTRACESIG, pid, (PTRACE_ARG3_TYPE)0, 0);
+
+	  if (realsig == SIGTHREADEXIT)
+	    {
+	      ptrace (PTRACE_CONT, PIDGET (pid), (PTRACE_ARG3_TYPE)0, 0);
+	      continue;
+	    }
+	}
+
+#ifdef SPARC
+      /* SPARC Lynx uses an byte reversed wait status; we must use the
+	 host macros to access it.  These lines just a copy of
+	 store_waitstatus.  We can't use CHILD_SPECIAL_WAITSTATUS
+	 because target.c can't include the Lynx <sys/wait.h>.  */
+      if (WIFEXITED (status))
+	{
+	  ourstatus->kind = TARGET_WAITKIND_EXITED;
+	  ourstatus->value.integer = WEXITSTATUS (status);
+	}
+      else if (!WIFSTOPPED (status))
+	{
+	  ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
+	  ourstatus->value.sig =
+	    target_signal_from_host (WTERMSIG (status));
+	}
+      else
+	{
+	  ourstatus->kind = TARGET_WAITKIND_STOPPED;
+	  ourstatus->value.sig =
+	    target_signal_from_host (WSTOPSIG (status));
+	}
+#else
+      store_waitstatus (ourstatus, status.w_status);
+#endif
+
+      return pid;
+    }
+}
+
+/* Return nonzero if the given thread is still alive.  */
+int
+child_thread_alive (pid)
+     int pid;
+{
+  /* Arggh.  Apparently pthread_kill only works for threads within
+     the process that calls pthread_kill.
+
+     We want to avoid the lynx signal extensions as they simply don't
+     map well to the generic gdb interface we want to keep.
+
+     All we want to do is determine if a particular thread is alive;
+     it appears as if we can just make a harmless thread specific
+     ptrace call to do that.  */
+  return (ptrace (PTRACE_THREADUSER, pid, 0, 0) != -1);
+}
+
+/* Resume execution of the inferior process.
+   If STEP is nonzero, single-step it.
+   If SIGNAL is nonzero, give it that signal.  */
+
+void
+child_resume (pid, step, signal)
+     int pid;
+     int step;
+     enum target_signal signal;
+{
+  int func;
+
+  errno = 0;
+
+  /* If pid == -1, then we want to step/continue all threads, else
+     we only want to step/continue a single thread.  */
+  if (pid == -1)
+    {
+      pid = inferior_pid;
+      func = step ? PTRACE_SINGLESTEP : PTRACE_CONT;
+    }
+  else
+    func = step ? PTRACE_SINGLESTEP_ONE : PTRACE_CONT_ONE;
+
+
+  /* An address of (PTRACE_ARG3_TYPE)1 tells ptrace to continue from where
+     it was.  (If GDB wanted it to start some other way, we have already
+     written a new PC value to the child.)
+
+     If this system does not support PT_STEP, a higher level function will
+     have called single_step() to transmute the step request into a
+     continue request (by setting breakpoints on all possible successor
+     instructions), so we don't have to worry about that here.  */
+
+  ptrace (func, pid, (PTRACE_ARG3_TYPE) 1, target_signal_to_host (signal));
+
+  if (errno)
+    perror_with_name ("ptrace");
+}
+
+/* Convert a Lynx process ID to a string.  Returns the string in a static
+   buffer.  */
+
+char *
+lynx_pid_to_str (pid)
+     int pid;
+{
+  static char buf[40];
+
+  sprintf (buf, "process %d thread %d", PIDGET (pid), TIDGET (pid));
+
+  return buf;
+}
+
+/* Extract the register values out of the core file and store
+   them where `read_register' will find them.
+
+   CORE_REG_SECT points to the register values themselves, read into memory.
+   CORE_REG_SIZE is the size of that area.
+   WHICH says which set of registers we are handling (0 = int, 2 = float
+         on machines where they are discontiguous).
+   REG_ADDR is the offset from u.u_ar0 to the register values relative to
+            core_reg_sect.  This is used with old-fashioned core files to
+	    locate the registers in a large upage-plus-stack ".reg" section.
+	    Original upage address X is at location core_reg_sect+x+reg_addr.
+ */
+
+static void
+fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
+     char *core_reg_sect;
+     unsigned core_reg_size;
+     int which;
+     CORE_ADDR reg_addr;
+{
+  struct st_entry s;
+  unsigned int regno;
+
+  for (regno = 0; regno < NUM_REGS; regno++)
+    if (regmap[regno] != -1)
+      supply_register (regno, core_reg_sect + offsetof (st_t, ec)
+		       + regmap[regno]);
+
+#ifdef SPARC
+/* Fetching this register causes all of the I & L regs to be read from the
+   stack and validated.  */
+
+  fetch_inferior_registers (I0_REGNUM);
+#endif
+}
+
+
+/* Register that we are able to handle lynx core file formats.
+   FIXME: is this really bfd_target_unknown_flavour? */
+
+static struct core_fns lynx_core_fns =
+{
+  bfd_target_unknown_flavour,
+  fetch_core_registers,
+  NULL
+};
+
+void
+_initialize_core_lynx ()
+{
+  add_core_fns (&lynx_core_fns);
+}