Initial revision

1 files changed, 397 insertions, 0 deletions

diff --git a/gdb/infptrace.c b/gdb/infptrace.c
new file mode 100644
index 0000000..03bb271
--- /dev/null
+++ b/gdb/infptrace.c
@@ -0,0 +1,397 @@
+/* Low level Unix child interface to ptrace, for GDB when running under Unix.
+   Copyright (C) 1988, 1989, 1990, 1991 Free Software Foundation, Inc.
+
+This file is part of GDB.
+
+GDB 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 1, or (at your option)
+any later version.
+
+GDB 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 GDB; see the file COPYING.  If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include <stdio.h>
+#include "defs.h"
+#include "param.h"
+#include "frame.h"
+#include "inferior.h"
+#include "target.h"
+
+#ifdef USG
+#include <sys/types.h>
+#endif
+
+#include <sys/param.h>
+#include <sys/dir.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <sys/ptrace.h>
+#if !defined (PT_KILL)
+#define PT_KILL 8
+#define PT_STEP 9
+#define PT_CONTINUE 7
+#define PT_READ_U 3
+#define PT_WRITE_U 6
+#define PT_READ_I 1
+#define PT_WRITE_I 4
+/* The Following Change is for a Sun */
+#define PT_WRITE_D 4
+#endif /* No PT_KILL.  */
+
+#ifndef PT_ATTACH
+#define PT_ATTACH PTRACE_ATTACH
+#endif
+#ifndef PT_DETACH
+#define PT_DETACH PTRACE_DETACH
+#endif
+
+#include "gdbcore.h"
+#include <sys/user.h>		/* After a.out.h  */
+#include <sys/file.h>
+#include <sys/stat.h>
+
+/* This function simply calls ptrace with the given arguments.  
+   It exists so that all calls to ptrace are isolated in this 
+   machine-dependent file. */
+int
+call_ptrace (request, pid, addr, data)
+     int request, pid, *addr, data;
+{
+  return ptrace (request, pid, addr, data);
+}
+
+#ifdef DEBUG_PTRACE
+/* For the rest of the file, use an extra level of indirection */
+/* This lets us breakpoint usefully on call_ptrace. */
+#define ptrace call_ptrace
+#endif
+
+/* This is used when GDB is exiting.  It gives less chance of error.*/
+
+void
+kill_inferior_fast ()
+{
+  if (inferior_pid == 0)
+    return;
+  ptrace (PT_KILL, inferior_pid, 0, 0);
+  wait ((int *)0);
+}
+
+void
+kill_inferior (args, from_tty)
+     char *args;
+     int from_tty;
+{
+  kill_inferior_fast ();
+  target_mourn_inferior ();
+}
+
+/* Resume execution of the inferior process.
+   If STEP is nonzero, single-step it.
+   If SIGNAL is nonzero, give it that signal.  */
+
+void
+child_resume (step, signal)
+     int step;
+     int signal;
+{
+  errno = 0;
+  /* An address of (int *)1 tells it 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 (step)
+    {
+#if defined (NO_SINGLE_STEP)
+      single_step (signal);
+#else /* Have single step.  */
+      ptrace (PT_STEP, inferior_pid, (int *)1, signal);
+#endif /* Have single step.  */
+    }
+  else
+    ptrace (PT_CONTINUE, inferior_pid, (int *)1, signal);
+  if (errno)
+    perror_with_name ("ptrace");
+}
+
+#ifdef ATTACH_DETACH
+/* Nonzero if we are debugging an attached process rather than
+   an inferior.  */
+extern int attach_flag;
+
+/* Start debugging the process whose number is PID.  */
+int
+attach (pid)
+     int pid;
+{
+  errno = 0;
+  ptrace (PT_ATTACH, pid, 0, 0);
+  if (errno)
+    perror_with_name ("ptrace");
+  attach_flag = 1;
+  return pid;
+}
+
+/* Stop debugging the process whose number is PID
+   and continue it with signal number SIGNAL.
+   SIGNAL = 0 means just continue it.  */
+
+void
+detach (signal)
+     int signal;
+{
+  errno = 0;
+  ptrace (PT_DETACH, inferior_pid, 1, signal);
+  if (errno)
+    perror_with_name ("ptrace");
+  attach_flag = 0;
+}
+#endif /* ATTACH_DETACH */
+
+#if !defined (FETCH_INFERIOR_REGISTERS)
+
+/* KERNEL_U_ADDR is the amount to subtract from u.u_ar0
+   to get the offset in the core file of the register values.  */
+#if defined (KERNEL_U_ADDR_BSD)
+/* Get kernel_u_addr using BSD-style nlist().  */
+CORE_ADDR kernel_u_addr;
+
+void
+_initialize_kernel_u_addr ()
+{
+  struct nlist names[2];
+
+  names[0].n_un.n_name = "_u";
+  names[1].n_un.n_name = NULL;
+  if (nlist ("/vmunix", names) == 0)
+    kernel_u_addr = names[0].n_value;
+  else
+    fatal ("Unable to get kernel u area address.");
+}
+#endif /* KERNEL_U_ADDR_BSD.  */
+
+#if defined (KERNEL_U_ADDR_HPUX)
+/* Get kernel_u_addr using HPUX-style nlist().  */
+CORE_ADDR kernel_u_addr;
+
+struct hpnlist {      
+        char *          n_name;
+        long            n_value;  
+        unsigned char   n_type;   
+        unsigned char   n_length;  
+        short           n_almod;   
+        short           n_unused;
+};
+static struct hpnlist nl[] = {{ "_u", -1, }, { (char *) 0, }};
+
+/* read the value of the u area from the hp-ux kernel */
+void _initialize_kernel_u_addr ()
+{
+    struct user u;
+    nlist ("/hp-ux", &nl);
+    kernel_u_addr = nl[0].n_value;
+}
+#endif /* KERNEL_U_ADDR_HPUX.  */
+
+#if !defined (offsetof)
+#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
+#endif
+
+/* U_REGS_OFFSET is the offset of the registers within the u area.  */
+#if !defined (U_REGS_OFFSET)
+#define U_REGS_OFFSET \
+  ptrace (PT_READ_U, inferior_pid, \
+	  (int *)(offsetof (struct user, u_ar0)), 0) - KERNEL_U_ADDR
+#endif
+
+/* Fetch one register.  */
+static void
+fetch_register (regno)
+     int regno;
+{
+  register unsigned int regaddr;
+  char buf[MAX_REGISTER_RAW_SIZE];
+  register int i;
+
+  /* Offset of registers within the u area.  */
+  unsigned int offset = U_REGS_OFFSET;
+
+  regaddr = register_addr (regno, offset);
+  for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
+    {
+      *(int *) &buf[i] = ptrace (PT_READ_U, inferior_pid, (int *)regaddr, 0);
+      regaddr += sizeof (int);
+    }
+  supply_register (regno, buf);
+}
+
+/* Fetch all registers, or just one, from the child process.
+   We should check for errors, but we don't.  FIXME.  */
+
+int
+fetch_inferior_registers (regno)
+     int regno;
+{
+  if (regno == -1)
+    for (regno = 0; regno < NUM_REGS; regno++)
+      fetch_register (regno);
+  else
+    fetch_register (regno);
+  return 0;
+}
+
+/* Registers we shouldn't try to store.  */
+#if !defined (CANNOT_STORE_REGISTER)
+#define CANNOT_STORE_REGISTER(regno) 0
+#endif
+
+/* 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).  */
+
+int
+store_inferior_registers (regno)
+     int regno;
+{
+  register unsigned int regaddr;
+  char buf[80];
+  extern char registers[];
+  register int i;
+  int result = 0;
+
+  unsigned int offset = U_REGS_OFFSET;
+
+  if (regno >= 0)
+    {
+      regaddr = register_addr (regno, offset);
+      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
+	{
+	  errno = 0;
+	  ptrace (PT_WRITE_U, inferior_pid, (int *)regaddr,
+		  *(int *) &registers[REGISTER_BYTE (regno) + i]);
+	  if (errno != 0)
+	    {
+	      sprintf (buf, "writing register number %d(%d)", regno, i);
+	      perror_with_name (buf);
+	      result = -1;
+	    }
+	  regaddr += sizeof(int);
+	}
+    }
+  else
+    {
+      for (regno = 0; regno < NUM_REGS; regno++)
+	{
+	  if (CANNOT_STORE_REGISTER (regno))
+	    continue;
+	  regaddr = register_addr (regno, offset);
+	  for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
+	    {
+	      errno = 0;
+	      ptrace (PT_WRITE_U, inferior_pid, (int *)regaddr,
+		      *(int *) &registers[REGISTER_BYTE (regno) + i]);
+	      if (errno != 0)
+		{
+		  sprintf (buf, "writing register number %d(%d)", regno, i);
+		  perror_with_name (buf);
+		  result = -1;
+		}
+	      regaddr += sizeof(int);
+	    }
+	}
+    }
+  return result;
+}
+#endif /* !defined (FETCH_INFERIOR_REGISTERS).  */
+
+/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
+   in the NEW_SUN_PTRACE case.
+   It ought to be straightforward.  But it appears that writing did
+   not write the data that I specified.  I cannot understand where
+   it got the data that it actually did write.  */
+
+/* Copy LEN bytes to or from inferior's memory starting at MEMADDR
+   to debugger memory starting at MYADDR.   Copy to inferior if
+   WRITE is nonzero.
+  
+   Returns the length copied, which is either the LEN argument or zero.
+   This xfer function does not do partial moves, since child_ops
+   doesn't allow memory operations to cross below us in the target stack
+   anyway.  */
+
+int
+child_xfer_memory (memaddr, myaddr, len, write)
+     CORE_ADDR memaddr;
+     char *myaddr;
+     int len;
+     int write;
+{
+  register int i;
+  /* Round starting address down to longword boundary.  */
+  register CORE_ADDR addr = memaddr & - sizeof (int);
+  /* Round ending address up; get number of longwords that makes.  */
+  register int count
+    = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
+  /* Allocate buffer of that many longwords.  */
+  register int *buffer = (int *) alloca (count * sizeof (int));
+
+  if (write)
+    {
+      /* Fill start and end extra bytes of buffer with existing memory data.  */
+
+      if (addr != memaddr || len < (int)sizeof (int)) {
+	/* Need part of initial word -- fetch it.  */
+        buffer[0] = ptrace (PT_READ_I, inferior_pid, (int *)addr, 0);
+      }
+
+      if (count > 1)		/* FIXME, avoid if even boundary */
+	{
+	  buffer[count - 1]
+	    = ptrace (PT_READ_I, inferior_pid,
+		      (int *)(addr + (count - 1) * sizeof (int)), 0);
+	}
+
+      /* Copy data to be written over corresponding part of buffer */
+
+      bcopy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
+
+      /* Write the entire buffer.  */
+
+      for (i = 0; i < count; i++, addr += sizeof (int))
+	{
+	  errno = 0;
+	  ptrace (PT_WRITE_D, inferior_pid, (int *)addr, buffer[i]);
+	  if (errno)
+	    {
+	      /* Using the appropriate one (I or D) is necessary for
+		 Gould NP1, at least.  */
+	      errno = 0;
+	      ptrace (PT_WRITE_I, inferior_pid, (int *)addr, buffer[i]);
+	    }
+	  if (errno)
+	    return 0;
+	}
+    }
+  else
+    {
+      /* Read all the longwords */
+      for (i = 0; i < count; i++, addr += sizeof (int))
+	{
+	  errno = 0;
+	  buffer[i] = ptrace (PT_READ_I, inferior_pid, (int *)addr, 0);
+	  if (errno)
+	    return 0;
+	  QUIT;
+	}
+
+      /* Copy appropriate bytes out of the buffer.  */
+      bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
+    }
+  return len;
+}