2012-01-26 Pedro Alves <palves@redhat.com>

[deliverable/binutils-gdb.git] / gdb / inf-ptrace.c

diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index 110e825363e64a2b5d338b14ef20520fcaa0b27f..396c2f7407a32bd42706d252ef5cead4bbd6ba52 100644 (file)
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -1,8 +1,7 @@
 /* Low-level child interface to ptrace.
 
-   Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
-   1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
-   Free Software Foundation, Inc.
+   Copyright (C) 1988-1996, 1998-2002, 2004-2012 Free Software
+   Foundation, Inc.
 
    This file is part of GDB.
 
@@ -582,6 +581,26 @@ inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object,
       return -1;
 
     case TARGET_OBJECT_AUXV:
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+      /* OpenBSD 4.5 has a new PIOD_READ_AUXV operation for the PT_IO
+        request that allows us to read the auxilliary vector.  Other
+        BSD's may follow if they feel the need to support PIE.  */
+      {
+       struct ptrace_io_desc piod;
+
+       if (writebuf)
+         return -1;
+       piod.piod_op = PIOD_READ_AUXV;
+       piod.piod_addr = readbuf;
+       piod.piod_offs = (void *) (long) offset;
+       piod.piod_len = len;
+
+       errno = 0;
+       if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+         /* Return the actual number of bytes read or written.  */
+         return piod.piod_len;
+      }
+#endif
       return -1;
 
     case TARGET_OBJECT_WCOOKIE:
@@ -619,6 +638,41 @@ inf_ptrace_pid_to_str (struct target_ops *ops, ptid_t ptid)
   return normal_pid_to_str (ptid);
 }
 
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+
+/* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
+   Return 0 if *READPTR is already at the end of the buffer.
+   Return -1 if there is insufficient buffer for a whole entry.
+   Return 1 if an entry was read into *TYPEP and *VALP.  */
+
+static int
+inf_ptrace_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
+                      gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
+{
+  struct type *int_type = builtin_type (target_gdbarch)->builtin_int;
+  struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr;
+  const int sizeof_auxv_type = TYPE_LENGTH (int_type);
+  const int sizeof_auxv_val = TYPE_LENGTH (ptr_type);
+  enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
+  gdb_byte *ptr = *readptr;
+
+  if (endptr == ptr)
+    return 0;
+
+  if (endptr - ptr < 2 * sizeof_auxv_val)
+    return -1;
+
+  *typep = extract_unsigned_integer (ptr, sizeof_auxv_type, byte_order);
+  ptr += sizeof_auxv_val;      /* Alignment.  */
+  *valp = extract_unsigned_integer (ptr, sizeof_auxv_val, byte_order);
+  ptr += sizeof_auxv_val;
+
+  *readptr = ptr;
+  return 1;
+}
+
+#endif
+
 /* Create a prototype ptrace target.  The client can override it with
    local methods.  */
 
@@ -644,6 +698,9 @@ inf_ptrace_target (void)
   t->to_pid_to_str = inf_ptrace_pid_to_str;
   t->to_stop = inf_ptrace_stop;
   t->to_xfer_partial = inf_ptrace_xfer_partial;
+#if defined (PT_IO) && defined (PIOD_READ_AUXV)
+  t->to_auxv_parse = inf_ptrace_auxv_parse;
+#endif
 
   return t;
 }