2008-07-03  Pedro Alves  <pedro@codesourcery.com>

	* monitor (monitor_ptid): New global.
	(monitor_open): Silently add the main task to GDB's thread list.
	(monitor_close, monitor_mourn_inferior): Silently delete the main
	task from GDB's thread list.
	(monitor_thread_alive, monitor_pid_to_str): New.
	(init_base_monitor_ops): Register monitor_thread_alive and
	monitor_pid_to_str.
	(_initialize_remote_monitors): Initialize monitor_ptid.

	* gdbthread.h (delete_thread_silent): Declare.
	* thread.c (delete_thread): Rename to ...
	(delete_thread_1): ... this.  Add "silent" parameter.  If silent,
	don't do exit notifications.
	(delete_thread, delete_thread_silent): New, as wrappers to
	delete_thread_1.

---
 gdb/gdbthread.h |    5 +++++
 gdb/monitor.c   |   49 ++++++++++++++++++++++++++++++++++++++++++++++++-
 gdb/thread.c    |   21 ++++++++++++++++++---
 3 files changed, 71 insertions(+), 4 deletions(-)

Index: src/gdb/monitor.c
===================================================================
--- src.orig/gdb/monitor.c	2008-07-03 16:15:04.000000000 +0100
+++ src/gdb/monitor.c	2008-07-03 16:21:04.000000000 +0100
@@ -106,6 +106,13 @@ static int dump_reg_flag;	/* Non-zero me
 static int first_time = 0;	/* is this the first time we're executing after 
 				   gaving created the child proccess? */
 
+
+/* This is the ptid we use while we're connected to a monitor.  It's
+   value is arbitrary, as monitor targets don't have a notion or
+   processes or thread, but we need something non-null to place in
+   inferior_ptid.  */
+static ptid_t monitor_ptid;
+
 #define TARGET_BUF_SIZE 2048
 
 /* Monitor specific debugging information.  Typically only useful to
@@ -808,7 +815,9 @@ monitor_open (char *args, struct monitor
   /* Start afresh.  */
   init_thread_list ();
 
-  inferior_ptid = pid_to_ptid (42000);	/* Make run command think we are busy... */
+  /* Make run command think we are busy...  */
+  inferior_ptid = monitor_ptid;
+  add_thread_silent (inferior_ptid);
 
   /* Give monitor_wait something to read */
 
@@ -834,6 +843,8 @@ monitor_close (int quitting)
     }
 
   monitor_desc = NULL;
+
+  delete_thread_silent (monitor_ptid);
 }
 
 /* Terminate the open connection to the remote debugger.  Use this
@@ -2002,6 +2013,7 @@ static void
 monitor_mourn_inferior (void)
 {
   unpush_target (targ_ops);
+  delete_thread_silent (monitor_ptid);
   generic_mourn_inferior ();	/* Do all the proper things now */
 }
 
@@ -2215,6 +2227,35 @@ monitor_get_dev_name (void)
   return dev_name;
 }
 
+/* Check to see if a thread is still alive.  */
+
+static int
+monitor_thread_alive (ptid_t ptid)
+{
+  if (ptid_equal (ptid, monitor_ptid))
+    /* The monitor's task is always alive.  */
+    return 1;
+
+  return 0;
+}
+
+/* Convert a thread ID to a string.  Returns the string in a static
+   buffer.  */
+
+static char *
+monitor_pid_to_str (ptid_t ptid)
+{
+  static char buf[64];
+
+  if (ptid_equal (monitor_ptid, ptid))
+    {
+      xsnprintf (buf, sizeof buf, "Thread <main>");
+      return buf;
+    }
+
+  return normal_pid_to_str (ptid);
+}
+
 static struct target_ops monitor_ops;
 
 static void
@@ -2238,6 +2279,8 @@ init_base_monitor_ops (void)
   monitor_ops.to_stop = monitor_stop;
   monitor_ops.to_rcmd = monitor_rcmd;
   monitor_ops.to_log_command = serial_log_command;
+  monitor_ops.to_thread_alive = monitor_thread_alive;
+  monitor_ops.to_pid_to_str = monitor_pid_to_str;
   monitor_ops.to_stratum = process_stratum;
   monitor_ops.to_has_all_memory = 1;
   monitor_ops.to_has_memory = 1;
@@ -2282,4 +2325,8 @@ is displayed."),
 			    NULL,
 			    NULL, /* FIXME: i18n: */
 			    &setdebuglist, &showdebuglist);
+
+  /* Yes, 42000 is arbitrary.  The only sense out of it, is that it
+     isn't 0.  */
+  monitor_ptid = ptid_build (42000, 0, 42000);
 }
Index: src/gdb/gdbthread.h
===================================================================
--- src.orig/gdb/gdbthread.h	2008-07-03 16:15:04.000000000 +0100
+++ src/gdb/gdbthread.h	2008-07-03 16:15:06.000000000 +0100
@@ -91,6 +91,11 @@ extern struct thread_info *add_thread_wi
 /* Delete an existing thread list entry.  */
 extern void delete_thread (ptid_t);
 
+/* Delete an existing thread list entry, and be quiet about it.  Used
+   after the process this thread having belonged to having already
+   exited, for example.  */
+extern void delete_thread_silent (ptid_t);
+
 /* Delete a step_resume_breakpoint from the thread database. */
 extern void delete_step_resume_breakpoint (void *);
 
Index: src/gdb/thread.c
===================================================================
--- src.orig/gdb/thread.c	2008-07-03 16:15:04.000000000 +0100
+++ src/gdb/thread.c	2008-07-03 16:15:06.000000000 +0100
@@ -153,8 +153,10 @@ add_thread (ptid_t ptid)
   return add_thread_with_info (ptid, NULL);
 }
 
-void
-delete_thread (ptid_t ptid)
+/* Delete thread PTID.  If SILENT, don't notify the observer of this
+   exit.  */
+static void
+delete_thread_1 (ptid_t ptid, int silent)
 {
   struct thread_info *tp, *tpprev;
 
@@ -172,11 +174,24 @@ delete_thread (ptid_t ptid)
   else
     thread_list = tp->next;
 
-  observer_notify_thread_exit (tp);
+  if (!silent)
+    observer_notify_thread_exit (tp);
 
   free_thread (tp);
 }
 
+void
+delete_thread (ptid_t ptid)
+{
+  delete_thread_1 (ptid, 0 /* not silent */);
+}
+
+void
+delete_thread_silent (ptid_t ptid)
+{
+  delete_thread_1 (ptid, 1 /* silent */);
+}
+
 static struct thread_info *
 find_thread_id (int num)
 {