/* Low level Unix child interface to ptrace, for GDB when running under Unix.
- Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998,
- 1999, 2000, 2001
+ Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
+ 1998, 1999, 2000, 2001, 2002
Free Software Foundation, Inc.
This file is part of GDB.
int
child_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
- struct mem_attrib *attrib ATTRIBUTE_UNUSED,
- struct target_ops *target)
+ struct mem_attrib *attrib, struct target_ops *target)
{
int i;
/* Round starting address down to longword boundary. */
PTRACE_XFER_TYPE *buffer;
struct cleanup *old_chain = NULL;
+#ifdef PT_IO
+ /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO request
+ that promises to be much more efficient in reading and writing
+ data in the traced process's address space. */
+
+ {
+ struct ptrace_io_desc piod;
+
+ /* NOTE: We assume that there are no distinct address spaces for
+ instruction and data. */
+ piod.piod_op = write ? PIOD_WRITE_D : PIOD_READ_D;
+ piod.piod_offs = (void *) memaddr;
+ piod.piod_addr = myaddr;
+ piod.piod_len = len;
+
+ if (ptrace (PT_IO, PIDGET (inferior_ptid), (caddr_t) &piod, 0) == -1)
+ {
+ /* If the PT_IO request is somehow not supported, fallback on
+ using PT_WRITE_D/PT_READ_D. Otherwise we will return zero
+ to indicate failure. */
+ if (errno != EINVAL)
+ return 0;
+ }
+ else
+ {
+ /* Return the actual number of bytes read or written. */
+ return piod.piod_len;
+ }
+ }
+#endif
+
/* Allocate buffer of that many longwords. */
if (len < GDB_MAX_ALLOCA)
{