X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fthread.c;h=7d889af90835a667a4620446e85087cdb9f0be88;hb=908fa2aaede2b3d1c33d167116101c2152e30616;hp=c36bb4a12f0ba201e1e42e34b9998da6c68d5d6e;hpb=611c83ae477b587e7d93636cc6c241d063bb799b;p=deliverable%2Fbinutils-gdb.git

diff --git a/gdb/thread.c b/gdb/thread.c
index c36bb4a12f..7d889af908 100644
--- a/gdb/thread.c
+++ b/gdb/thread.c
@@ -1,7 +1,6 @@
 /* Multi-process/thread control for GDB, the GNU debugger.
 
-   Copyright (C) 1986, 1987, 1988, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
-   2000, 2001, 2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
+   Copyright (C) 1986-2013 Free Software Foundation, Inc.
 
    Contributed by Lynx Real-Time Systems, Inc.  Los Gatos, CA.
 
@@ -33,27 +32,31 @@
 #include "gdbcmd.h"
 #include "regcache.h"
 #include "gdb.h"
-#include "gdb_string.h"
+#include <string.h>
+#include "btrace.h"
 
 #include <ctype.h>
 #include <sys/types.h>
 #include <signal.h>
 #include "ui-out.h"
 #include "observer.h"
+#include "annotate.h"
+#include "cli/cli-decode.h"
+#include "gdb_regex.h"
+#include "cli/cli-utils.h"
+#include "continuations.h"
 
-/* Definition of struct thread_info exported to gdbthread.h */
+/* Definition of struct thread_info exported to gdbthread.h.  */
 
-/* Prototypes for exported functions. */
+/* Prototypes for exported functions.  */
 
 void _initialize_thread (void);
 
-/* Prototypes for local functions. */
+/* Prototypes for local functions.  */
 
-static struct thread_info *thread_list = NULL;
+struct thread_info *thread_list = NULL;
 static int highest_thread_num;
 
-static struct thread_info *find_thread_id (int num);
-
 static void thread_command (char *tidstr, int from_tty);
 static void thread_apply_all_command (char *, int);
 static int thread_alive (struct thread_info *);
@@ -62,38 +65,89 @@ static void thread_apply_command (char *, int);
 static void restore_current_thread (ptid_t);
 static void prune_threads (void);
 
-void
-delete_step_resume_breakpoint (void *arg)
+/* Data to cleanup thread array.  */
+
+struct thread_array_cleanup
 {
-  struct breakpoint **breakpointp = (struct breakpoint **) arg;
-  struct thread_info *tp;
+  /* Array of thread pointers used to set
+     reference count.  */
+  struct thread_info **tp_array;
 
-  if (*breakpointp != NULL)
+  /* Thread count in the array.  */
+  int count;
+};
+
+
+struct thread_info*
+inferior_thread (void)
+{
+  struct thread_info *tp = find_thread_ptid (inferior_ptid);
+  gdb_assert (tp);
+  return tp;
+}
+
+void
+delete_step_resume_breakpoint (struct thread_info *tp)
+{
+  if (tp && tp->control.step_resume_breakpoint)
     {
-      delete_breakpoint (*breakpointp);
-      for (tp = thread_list; tp; tp = tp->next)
-	if (tp->step_resume_breakpoint == *breakpointp)
-	  tp->step_resume_breakpoint = NULL;
+      delete_breakpoint (tp->control.step_resume_breakpoint);
+      tp->control.step_resume_breakpoint = NULL;
+    }
+}
 
-      *breakpointp = NULL;
+void
+delete_exception_resume_breakpoint (struct thread_info *tp)
+{
+  if (tp && tp->control.exception_resume_breakpoint)
+    {
+      delete_breakpoint (tp->control.exception_resume_breakpoint);
+      tp->control.exception_resume_breakpoint = NULL;
     }
 }
 
 static void
-free_thread (struct thread_info *tp)
+clear_thread_inferior_resources (struct thread_info *tp)
 {
   /* NOTE: this will take care of any left-over step_resume breakpoints,
      but not any user-specified thread-specific breakpoints.  We can not
      delete the breakpoint straight-off, because the inferior might not
      be stopped at the moment.  */
-  if (tp->step_resume_breakpoint)
-    tp->step_resume_breakpoint->disposition = disp_del_at_next_stop;
+  if (tp->control.step_resume_breakpoint)
+    {
+      tp->control.step_resume_breakpoint->disposition = disp_del_at_next_stop;
+      tp->control.step_resume_breakpoint = NULL;
+    }
 
-  /* FIXME: do I ever need to call the back-end to give it a
-     chance at this private data before deleting the thread?  */
+  if (tp->control.exception_resume_breakpoint)
+    {
+      tp->control.exception_resume_breakpoint->disposition
+	= disp_del_at_next_stop;
+      tp->control.exception_resume_breakpoint = NULL;
+    }
+
+  delete_longjmp_breakpoint_at_next_stop (tp->num);
+
+  bpstat_clear (&tp->control.stop_bpstat);
+
+  btrace_teardown (tp);
+
+  do_all_intermediate_continuations_thread (tp, 1);
+  do_all_continuations_thread (tp, 1);
+}
+
+static void
+free_thread (struct thread_info *tp)
+{
   if (tp->private)
-    xfree (tp->private);
+    {
+      if (tp->private_dtor)
+	tp->private_dtor (tp->private);
+      else
+	xfree (tp->private);
+    }
 
+  xfree (tp->name);
   xfree (tp);
 }
 
@@ -103,6 +157,7 @@ init_thread_list (void)
   struct thread_info *tp, *tpnext;
 
   highest_thread_num = 0;
+
   if (!thread_list)
     return;
 
@@ -115,18 +170,74 @@ init_thread_list (void)
   thread_list = NULL;
 }
 
-struct thread_info *
-add_thread_silent (ptid_t ptid)
+/* Allocate a new thread with target id PTID and add it to the thread
+   list.  */
+
+static struct thread_info *
+new_thread (ptid_t ptid)
 {
   struct thread_info *tp;
 
-  tp = (struct thread_info *) xmalloc (sizeof (*tp));
-  memset (tp, 0, sizeof (*tp));
+  tp = xcalloc (1, sizeof (*tp));
+
   tp->ptid = ptid;
   tp->num = ++highest_thread_num;
   tp->next = thread_list;
   thread_list = tp;
 
+  /* Nothing to follow yet.  */
+  tp->pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+  tp->state = THREAD_STOPPED;
+
+  return tp;
+}
+
+struct thread_info *
+add_thread_silent (ptid_t ptid)
+{
+  struct thread_info *tp;
+
+  tp = find_thread_ptid (ptid);
+  if (tp)
+    /* Found an old thread with the same id.  It has to be dead,
+       otherwise we wouldn't be adding a new thread with the same id.
+       The OS is reusing this id --- delete it, and recreate a new
+       one.  */
+    {
+      /* In addition to deleting the thread, if this is the current
+	 thread, then we need to take care that delete_thread doesn't
+	 really delete the thread if it is inferior_ptid.  Create a
+	 new template thread in the list with an invalid ptid, switch
+	 to it, delete the original thread, reset the new thread's
+	 ptid, and switch to it.  */
+
+      if (ptid_equal (inferior_ptid, ptid))
+	{
+	  tp = new_thread (null_ptid);
+
+	  /* Make switch_to_thread not read from the thread.  */
+	  tp->state = THREAD_EXITED;
+	  switch_to_thread (null_ptid);
+
+	  /* Now we can delete it.  */
+	  delete_thread (ptid);
+
+	  /* Now reset its ptid, and reswitch inferior_ptid to it.  */
+	  tp->ptid = ptid;
+	  tp->state = THREAD_STOPPED;
+	  switch_to_thread (ptid);
+
+	  observer_notify_new_thread (tp);
+
+	  /* All done.  */
+	  return tp;
+	}
+      else
+	/* Just go ahead and delete it.  */
+	delete_thread (ptid);
+    }
+
+  tp = new_thread (ptid);
   observer_notify_new_thread (tp);
 
   return tp;
@@ -141,7 +252,8 @@ add_thread_with_info (ptid_t ptid, struct private_thread_info *private)
 
   if (print_thread_events)
     printf_unfiltered (_("[New %s]\n"), target_pid_to_str (ptid));
-  
+
+  annotate_new_thread ();
   return result;
 }
 
@@ -151,8 +263,10 @@ 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;
 
@@ -165,17 +279,60 @@ delete_thread (ptid_t ptid)
   if (!tp)
     return;
 
+  /* If this is the current thread, or there's code out there that
+     relies on it existing (refcount > 0) we can't delete yet.  Mark
+     it as exited, and notify it.  */
+  if (tp->refcount > 0
+      || ptid_equal (tp->ptid, inferior_ptid))
+    {
+      if (tp->state != THREAD_EXITED)
+	{
+	  observer_notify_thread_exit (tp, silent);
+
+	  /* Tag it as exited.  */
+	  tp->state = THREAD_EXITED;
+
+	  /* Clear breakpoints, etc. associated with this thread.  */
+	  clear_thread_inferior_resources (tp);
+	}
+
+       /* Will be really deleted some other time.  */
+       return;
+     }
+
+  /* Notify thread exit, but only if we haven't already.  */
+  if (tp->state != THREAD_EXITED)
+    observer_notify_thread_exit (tp, silent);
+
+  /* Tag it as exited.  */
+  tp->state = THREAD_EXITED;
+  clear_thread_inferior_resources (tp);
+
   if (tpprev)
     tpprev->next = tp->next;
   else
     thread_list = tp->next;
 
-  observer_notify_thread_exit (tp);
-
   free_thread (tp);
 }
 
-static struct thread_info *
+/* Delete thread PTID and notify of thread exit.  If this is
+   inferior_ptid, don't actually delete it, but tag it as exited and
+   do the notification.  If PTID is the user selected thread, clear
+   it.  */
+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 */);
+}
+
+struct thread_info *
 find_thread_id (int num)
 {
   struct thread_info *tp;
@@ -189,7 +346,7 @@ find_thread_id (int num)
 
 /* Find a thread_info by matching PTID.  */
 struct thread_info *
-find_thread_pid (ptid_t ptid)
+find_thread_ptid (ptid_t ptid)
 {
   struct thread_info *tp;
 
@@ -218,13 +375,28 @@ struct thread_info *
 iterate_over_threads (int (*callback) (struct thread_info *, void *),
 		      void *data)
 {
+  struct thread_info *tp, *next;
+
+  for (tp = thread_list; tp; tp = next)
+    {
+      next = tp->next;
+      if ((*callback) (tp, data))
+	return tp;
+    }
+
+  return NULL;
+}
+
+int
+thread_count (void)
+{
+  int result = 0;
   struct thread_info *tp;
 
   for (tp = thread_list; tp; tp = tp->next)
-    if ((*callback) (tp, data))
-      return tp;
+    ++result;
 
-  return NULL;
+  return result;  
 }
 
 int
@@ -255,6 +427,7 @@ ptid_t
 thread_id_to_pid (int num)
 {
   struct thread_info *thread = find_thread_id (num);
+
   if (thread)
     return thread->ptid;
   else
@@ -270,36 +443,91 @@ in_thread_list (ptid_t ptid)
     if (ptid_equal (tp->ptid, ptid))
       return 1;
 
-  return 0;			/* Never heard of 'im */
+  return 0;			/* Never heard of 'im.  */
+}
+
+/* Finds the first thread of the inferior given by PID.  If PID is -1,
+   return the first thread in the list.  */
+
+struct thread_info *
+first_thread_of_process (int pid)
+{
+  struct thread_info *tp, *ret = NULL;
+
+  for (tp = thread_list; tp; tp = tp->next)
+    if (pid == -1 || ptid_get_pid (tp->ptid) == pid)
+      if (ret == NULL || tp->num < ret->num)
+	ret = tp;
+
+  return ret;
+}
+
+struct thread_info *
+any_thread_of_process (int pid)
+{
+  struct thread_info *tp;
+
+  for (tp = thread_list; tp; tp = tp->next)
+    if (ptid_get_pid (tp->ptid) == pid)
+      return tp;
+
+  return NULL;
+}
+
+struct thread_info *
+any_live_thread_of_process (int pid)
+{
+  struct thread_info *tp;
+  struct thread_info *tp_executing = NULL;
+
+  for (tp = thread_list; tp; tp = tp->next)
+    if (tp->state != THREAD_EXITED && ptid_get_pid (tp->ptid) == pid)
+      {
+	if (tp->executing)
+	  tp_executing = tp;
+	else
+	  return tp;
+      }
+
+  return tp_executing;
 }
 
 /* Print a list of thread ids currently known, and the total number of
-   threads. To be used from within catch_errors. */
+   threads.  To be used from within catch_errors.  */
 static int
 do_captured_list_thread_ids (struct ui_out *uiout, void *arg)
 {
   struct thread_info *tp;
   int num = 0;
   struct cleanup *cleanup_chain;
+  int current_thread = -1;
 
-  prune_threads ();
-  target_find_new_threads ();
+  update_thread_list ();
 
   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout, "thread-ids");
 
   for (tp = thread_list; tp; tp = tp->next)
     {
+      if (tp->state == THREAD_EXITED)
+	continue;
+
+      if (ptid_equal (tp->ptid, inferior_ptid))
+	current_thread = tp->num;
+
       num++;
       ui_out_field_int (uiout, "thread-id", tp->num);
     }
 
   do_cleanups (cleanup_chain);
+
+  if (current_thread != -1)
+    ui_out_field_int (uiout, "current-thread-id", current_thread);
   ui_out_field_int (uiout, "number-of-threads", num);
   return GDB_RC_OK;
 }
 
 /* Official gdblib interface function to get a list of thread ids and
-   the total number. */
+   the total number.  */
 enum gdb_rc
 gdb_list_thread_ids (struct ui_out *uiout, char **error_message)
 {
@@ -309,170 +537,413 @@ gdb_list_thread_ids (struct ui_out *uiout, char **error_message)
   return GDB_RC_OK;
 }
 
-/* Load infrun state for the thread PID.  */
+/* Return true if TP is an active thread.  */
+static int
+thread_alive (struct thread_info *tp)
+{
+  if (tp->state == THREAD_EXITED)
+    return 0;
+  if (!target_thread_alive (tp->ptid))
+    return 0;
+  return 1;
+}
+
+static void
+prune_threads (void)
+{
+  struct thread_info *tp, *next;
+
+  for (tp = thread_list; tp; tp = next)
+    {
+      next = tp->next;
+      if (!thread_alive (tp))
+	delete_thread (tp->ptid);
+    }
+}
 
 void
-load_infrun_state (ptid_t ptid,
-		   CORE_ADDR *prev_pc,
-		   int *trap_expected,
-		   struct breakpoint **step_resume_breakpoint,
-		   CORE_ADDR *step_range_start,
-		   CORE_ADDR *step_range_end,
-		   struct frame_id *step_frame_id,
-		   int *stepping_over_breakpoint,
-		   int *stepping_through_solib_after_catch,
-		   bpstat *stepping_through_solib_catchpoints,
-		   int *current_line,
-		   struct symtab **current_symtab)
+thread_change_ptid (ptid_t old_ptid, ptid_t new_ptid)
 {
+  struct inferior *inf;
   struct thread_info *tp;
 
-  /* If we can't find the thread, then we're debugging a single threaded
-     process.  No need to do anything in that case.  */
-  tp = find_thread_id (pid_to_thread_id (ptid));
-  if (tp == NULL)
-    return;
+  /* It can happen that what we knew as the target inferior id
+     changes.  E.g, target remote may only discover the remote process
+     pid after adding the inferior to GDB's list.  */
+  inf = find_inferior_pid (ptid_get_pid (old_ptid));
+  inf->pid = ptid_get_pid (new_ptid);
 
-  *prev_pc = tp->prev_pc;
-  *trap_expected = tp->trap_expected;
-  *step_resume_breakpoint = tp->step_resume_breakpoint;
-  *step_range_start = tp->step_range_start;
-  *step_range_end = tp->step_range_end;
-  *step_frame_id = tp->step_frame_id;
-  *stepping_over_breakpoint = tp->stepping_over_breakpoint;
-  *stepping_through_solib_after_catch =
-    tp->stepping_through_solib_after_catch;
-  *stepping_through_solib_catchpoints =
-    tp->stepping_through_solib_catchpoints;
-  *current_line = tp->current_line;
-  *current_symtab = tp->current_symtab;
-}
+  tp = find_thread_ptid (old_ptid);
+  tp->ptid = new_ptid;
 
-/* Save infrun state for the thread PID.  */
+  observer_notify_thread_ptid_changed (old_ptid, new_ptid);
+}
 
 void
-save_infrun_state (ptid_t ptid,
-		   CORE_ADDR prev_pc,
-		   int trap_expected,
-		   struct breakpoint *step_resume_breakpoint,
-		   CORE_ADDR step_range_start,
-		   CORE_ADDR step_range_end,
-		   const struct frame_id *step_frame_id,
-		   int stepping_over_breakpoint,
-		   int stepping_through_solib_after_catch,
-		   bpstat stepping_through_solib_catchpoints,
-		   int current_line,
-		   struct symtab *current_symtab)
+set_running (ptid_t ptid, int running)
 {
   struct thread_info *tp;
+  int all = ptid_equal (ptid, minus_one_ptid);
 
-  /* If we can't find the thread, then we're debugging a single-threaded
-     process.  Nothing to do in that case.  */
-  tp = find_thread_id (pid_to_thread_id (ptid));
-  if (tp == NULL)
-    return;
+  /* We try not to notify the observer if no thread has actually changed 
+     the running state -- merely to reduce the number of messages to 
+     frontend.  Frontend is supposed to handle multiple *running just fine.  */
+  if (all || ptid_is_pid (ptid))
+    {
+      int any_started = 0;
 
-  tp->prev_pc = prev_pc;
-  tp->trap_expected = trap_expected;
-  tp->step_resume_breakpoint = step_resume_breakpoint;
-  tp->step_range_start = step_range_start;
-  tp->step_range_end = step_range_end;
-  tp->step_frame_id = (*step_frame_id);
-  tp->stepping_over_breakpoint = stepping_over_breakpoint;
-  tp->stepping_through_solib_after_catch = stepping_through_solib_after_catch;
-  tp->stepping_through_solib_catchpoints = stepping_through_solib_catchpoints;
-  tp->current_line = current_line;
-  tp->current_symtab = current_symtab;
+      for (tp = thread_list; tp; tp = tp->next)
+	if (all || ptid_get_pid (tp->ptid) == ptid_get_pid (ptid))
+	  {
+	    if (tp->state == THREAD_EXITED)
+	      continue;
+	    if (running && tp->state == THREAD_STOPPED)
+	      any_started = 1;
+	    tp->state = running ? THREAD_RUNNING : THREAD_STOPPED;
+	  }
+      if (any_started)
+	observer_notify_target_resumed (ptid);
+    }
+  else
+    {
+      int started = 0;
+
+      tp = find_thread_ptid (ptid);
+      gdb_assert (tp);
+      gdb_assert (tp->state != THREAD_EXITED);
+      if (running && tp->state == THREAD_STOPPED)
+ 	started = 1;
+      tp->state = running ? THREAD_RUNNING : THREAD_STOPPED;
+      if (started)
+  	observer_notify_target_resumed (ptid);
+    }
 }
 
-/* Return true if TP is an active thread. */
 static int
-thread_alive (struct thread_info *tp)
+is_thread_state (ptid_t ptid, enum thread_state state)
 {
-  if (PIDGET (tp->ptid) == -1)
-    return 0;
-  if (!target_thread_alive (tp->ptid))
+  struct thread_info *tp;
+
+  tp = find_thread_ptid (ptid);
+  gdb_assert (tp);
+  return tp->state == state;
+}
+
+int
+is_stopped (ptid_t ptid)
+{
+  return is_thread_state (ptid, THREAD_STOPPED);
+}
+
+int
+is_exited (ptid_t ptid)
+{
+  return is_thread_state (ptid, THREAD_EXITED);
+}
+
+int
+is_running (ptid_t ptid)
+{
+  return is_thread_state (ptid, THREAD_RUNNING);
+}
+
+int
+any_running (void)
+{
+  struct thread_info *tp;
+
+  for (tp = thread_list; tp; tp = tp->next)
+    if (tp->state == THREAD_RUNNING)
+      return 1;
+
+  return 0;
+}
+
+int
+is_executing (ptid_t ptid)
+{
+  struct thread_info *tp;
+
+  tp = find_thread_ptid (ptid);
+  gdb_assert (tp);
+  return tp->executing;
+}
+
+void
+set_executing (ptid_t ptid, int executing)
+{
+  struct thread_info *tp;
+  int all = ptid_equal (ptid, minus_one_ptid);
+
+  if (all || ptid_is_pid (ptid))
     {
-      tp->ptid = pid_to_ptid (-1);	/* Mark it as dead */
-      return 0;
+      for (tp = thread_list; tp; tp = tp->next)
+	if (all || ptid_get_pid (tp->ptid) == ptid_get_pid (ptid))
+	  tp->executing = executing;
+    }
+  else
+    {
+      tp = find_thread_ptid (ptid);
+      gdb_assert (tp);
+      tp->executing = executing;
     }
-  return 1;
 }
 
-static void
-prune_threads (void)
+void
+set_stop_requested (ptid_t ptid, int stop)
 {
-  struct thread_info *tp, *next;
+  struct thread_info *tp;
+  int all = ptid_equal (ptid, minus_one_ptid);
 
-  for (tp = thread_list; tp; tp = next)
+  if (all || ptid_is_pid (ptid))
     {
-      next = tp->next;
-      if (!thread_alive (tp))
-	delete_thread (tp->ptid);
+      for (tp = thread_list; tp; tp = tp->next)
+	if (all || ptid_get_pid (tp->ptid) == ptid_get_pid (ptid))
+	  tp->stop_requested = stop;
+    }
+  else
+    {
+      tp = find_thread_ptid (ptid);
+      gdb_assert (tp);
+      tp->stop_requested = stop;
     }
+
+  /* Call the stop requested observer so other components of GDB can
+     react to this request.  */
+  if (stop)
+    observer_notify_thread_stop_requested (ptid);
+}
+
+void
+finish_thread_state (ptid_t ptid)
+{
+  struct thread_info *tp;
+  int all;
+  int any_started = 0;
+
+  all = ptid_equal (ptid, minus_one_ptid);
+
+  if (all || ptid_is_pid (ptid))
+    {
+      for (tp = thread_list; tp; tp = tp->next)
+	{
+ 	  if (tp->state == THREAD_EXITED)
+  	    continue;
+	  if (all || ptid_get_pid (ptid) == ptid_get_pid (tp->ptid))
+	    {
+	      if (tp->executing && tp->state == THREAD_STOPPED)
+		any_started = 1;
+	      tp->state = tp->executing ? THREAD_RUNNING : THREAD_STOPPED;
+	    }
+	}
+    }
+  else
+    {
+      tp = find_thread_ptid (ptid);
+      gdb_assert (tp);
+      if (tp->state != THREAD_EXITED)
+	{
+	  if (tp->executing && tp->state == THREAD_STOPPED)
+	    any_started = 1;
+	  tp->state = tp->executing ? THREAD_RUNNING : THREAD_STOPPED;
+	}
+    }
+
+  if (any_started)
+    observer_notify_target_resumed (ptid);
+}
+
+void
+finish_thread_state_cleanup (void *arg)
+{
+  ptid_t *ptid_p = arg;
+
+  gdb_assert (arg);
+
+  finish_thread_state (*ptid_p);
+}
+
+int
+pc_in_thread_step_range (CORE_ADDR pc, struct thread_info *thread)
+{
+  return (pc >= thread->control.step_range_start
+	  && pc < thread->control.step_range_end);
 }
 
 /* Prints the list of threads and their details on UIOUT.
-   This is a version of 'info_thread_command' suitable for
-   use from MI.  
-   If REQESTED_THREAD is not -1, it's the GDB id of the thread
+   This is a version of 'info_threads_command' suitable for
+   use from MI.
+   If REQUESTED_THREAD is not -1, it's the GDB id of the thread
    that should be printed.  Otherwise, all threads are
-   printed.  */
+   printed.
+   If PID is not -1, only print threads from the process PID.
+   Otherwise, threads from all attached PIDs are printed.
+   If both REQUESTED_THREAD and PID are not -1, then the thread
+   is printed if it belongs to the specified process.  Otherwise,
+   an error is raised.  */
 void
-print_thread_info (struct ui_out *uiout, int requested_thread)
+print_thread_info (struct ui_out *uiout, char *requested_threads, int pid)
 {
   struct thread_info *tp;
   ptid_t current_ptid;
-  struct frame_info *cur_frame;
   struct cleanup *old_chain;
-  struct frame_id saved_frame_id;
-  char *extra_info;
+  char *extra_info, *name, *target_id;
   int current_thread = -1;
 
-  /* Backup current thread and selected frame.  */
-  saved_frame_id = get_frame_id (get_selected_frame (NULL));
-  old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
+  update_thread_list ();
+  current_ptid = inferior_ptid;
 
-  make_cleanup_ui_out_list_begin_end (uiout, "threads");
+  /* We'll be switching threads temporarily.  */
+  old_chain = make_cleanup_restore_current_thread ();
+
+  /* For backward compatibility, we make a list for MI.  A table is
+     preferable for the CLI, though, because it shows table
+     headers.  */
+  if (ui_out_is_mi_like_p (uiout))
+    make_cleanup_ui_out_list_begin_end (uiout, "threads");
+  else
+    {
+      int n_threads = 0;
+
+      for (tp = thread_list; tp; tp = tp->next)
+	{
+	  if (!number_is_in_list (requested_threads, tp->num))
+	    continue;
+
+	  if (pid != -1 && ptid_get_pid (tp->ptid) != pid)
+	    continue;
+
+	  if (tp->state == THREAD_EXITED)
+	    continue;
+
+	  ++n_threads;
+	}
+
+      if (n_threads == 0)
+	{
+	  if (requested_threads == NULL || *requested_threads == '\0')
+	    ui_out_message (uiout, 0, _("No threads.\n"));
+	  else
+	    ui_out_message (uiout, 0, _("No threads match '%s'.\n"),
+			    requested_threads);
+	  do_cleanups (old_chain);
+	  return;
+	}
+
+      make_cleanup_ui_out_table_begin_end (uiout, 4, n_threads, "threads");
+
+      ui_out_table_header (uiout, 1, ui_left, "current", "");
+      ui_out_table_header (uiout, 4, ui_left, "id", "Id");
+      ui_out_table_header (uiout, 17, ui_left, "target-id", "Target Id");
+      ui_out_table_header (uiout, 1, ui_left, "frame", "Frame");
+      ui_out_table_body (uiout);
+    }
 
-  prune_threads ();
-  target_find_new_threads ();
-  current_ptid = inferior_ptid;
   for (tp = thread_list; tp; tp = tp->next)
     {
       struct cleanup *chain2;
+      int core;
 
-      if (requested_thread != -1 && tp->num != requested_thread)
+      if (!number_is_in_list (requested_threads, tp->num))
 	continue;
 
-      chain2 = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
+      if (pid != -1 && ptid_get_pid (tp->ptid) != pid)
+	{
+	  if (requested_threads != NULL && *requested_threads != '\0')
+	    error (_("Requested thread not found in requested process"));
+	  continue;
+	}
 
       if (ptid_equal (tp->ptid, current_ptid))
+	current_thread = tp->num;
+
+      if (tp->state == THREAD_EXITED)
+	continue;
+
+      chain2 = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
+
+      if (ui_out_is_mi_like_p (uiout))
 	{
-	  current_thread = tp->num;
-	  ui_out_text (uiout, "* ");
+	  /* Compatibility.  */
+	  if (ptid_equal (tp->ptid, current_ptid))
+	    ui_out_text (uiout, "* ");
+	  else
+	    ui_out_text (uiout, "  ");
 	}
       else
-	ui_out_text (uiout, "  ");
+	{
+	  if (ptid_equal (tp->ptid, current_ptid))
+	    ui_out_field_string (uiout, "current", "*");
+	  else
+	    ui_out_field_skip (uiout, "current");
+	}
 
       ui_out_field_int (uiout, "id", tp->num);
-      ui_out_text (uiout, " ");
-      ui_out_field_string (uiout, "target-id", target_tid_to_str (tp->ptid));
 
+      /* For the CLI, we stuff everything into the target-id field.
+	 This is a gross hack to make the output come out looking
+	 correct.  The underlying problem here is that ui-out has no
+	 way to specify that a field's space allocation should be
+	 shared by several fields.  For MI, we do the right thing
+	 instead.  */
+
+      target_id = target_pid_to_str (tp->ptid);
       extra_info = target_extra_thread_info (tp);
-      if (extra_info)
+      name = tp->name ? tp->name : target_thread_name (tp);
+
+      if (ui_out_is_mi_like_p (uiout))
+	{
+	  ui_out_field_string (uiout, "target-id", target_id);
+	  if (extra_info)
+	    ui_out_field_string (uiout, "details", extra_info);
+	  if (name)
+	    ui_out_field_string (uiout, "name", name);
+	}
+      else
+	{
+	  struct cleanup *str_cleanup;
+	  char *contents;
+
+	  if (extra_info && name)
+	    contents = xstrprintf ("%s \"%s\" (%s)", target_id,
+				   name, extra_info);
+	  else if (extra_info)
+	    contents = xstrprintf ("%s (%s)", target_id, extra_info);
+	  else if (name)
+	    contents = xstrprintf ("%s \"%s\"", target_id, name);
+	  else
+	    contents = xstrdup (target_id);
+	  str_cleanup = make_cleanup (xfree, contents);
+
+	  ui_out_field_string (uiout, "target-id", contents);
+	  do_cleanups (str_cleanup);
+	}
+
+      if (tp->state == THREAD_RUNNING)
+	ui_out_text (uiout, "(running)\n");
+      else
+	{
+	  /* The switch below puts us at the top of the stack (leaf
+	     frame).  */
+	  switch_to_thread (tp->ptid);
+	  print_stack_frame (get_selected_frame (NULL),
+			     /* For MI output, print frame level.  */
+			     ui_out_is_mi_like_p (uiout),
+			     LOCATION, 0);
+	}
+
+      if (ui_out_is_mi_like_p (uiout))
 	{
-	  ui_out_text (uiout, " (");
-	  ui_out_field_string (uiout, "details", extra_info);
-	  ui_out_text (uiout, ")");
+	  char *state = "stopped";
+
+	  if (tp->state == THREAD_RUNNING)
+	    state = "running";
+	  ui_out_field_string (uiout, "state", state);
 	}
-      ui_out_text (uiout, "  ");
-      /* That switch put us at the top of the stack (leaf frame).  */
-      switch_to_thread (tp->ptid);
-      print_stack_frame (get_selected_frame (NULL), 
-			 /* For MI output, print frame level.  */
-			 ui_out_is_mi_like_p (uiout),
-			 LOCATION);
+
+      core = target_core_of_thread (tp->ptid);
+      if (ui_out_is_mi_like_p (uiout) && core != -1)
+	ui_out_field_int (uiout, "core", core);
 
       do_cleanups (chain2);
     }
@@ -481,74 +952,137 @@ print_thread_info (struct ui_out *uiout, int requested_thread)
      the "info threads" command.  */
   do_cleanups (old_chain);
 
-  if (requested_thread == -1)
+  if (pid == -1 && requested_threads == NULL)
     {
-      gdb_assert (current_thread != -1 || !thread_list);
+      gdb_assert (current_thread != -1
+		  || !thread_list
+		  || ptid_equal (inferior_ptid, null_ptid));
       if (current_thread != -1 && ui_out_is_mi_like_p (uiout))
 	ui_out_field_int (uiout, "current-thread-id", current_thread);
-    }
 
-  /*  If case we were not able to find the original frame, print the
-      new selected frame.  */
-  if (frame_find_by_id (saved_frame_id) == NULL)
-    {
-      warning (_("Couldn't restore frame in current thread, at frame 0"));
-      /* For MI, we should probably have a notification about
-	 current frame change.  But this error is not very likely, so
-	 don't bother for now.  */
-      if (!ui_out_is_mi_like_p (uiout))
-	print_stack_frame (get_selected_frame (NULL), 0, LOCATION);
+      if (current_thread != -1 && is_exited (current_ptid))
+	ui_out_message (uiout, 0, "\n\
+The current thread <Thread ID %d> has terminated.  See `help thread'.\n",
+			current_thread);
+      else if (thread_list
+	       && current_thread == -1
+	       && ptid_equal (current_ptid, null_ptid))
+	ui_out_message (uiout, 0, "\n\
+No selected thread.  See `help thread'.\n");
     }
 }
 
-
 /* Print information about currently known threads 
 
- * Note: this has the drawback that it _really_ switches
- *       threads, which frees the frame cache.  A no-side
- *       effects info-threads command would be nicer.
- */
+   Optional ARG is a thread id, or list of thread ids.
+
+   Note: this has the drawback that it _really_ switches
+         threads, which frees the frame cache.  A no-side
+         effects info-threads command would be nicer.  */
 
 static void
 info_threads_command (char *arg, int from_tty)
 {
-  print_thread_info (uiout, -1);
+  print_thread_info (current_uiout, arg, -1);
 }
 
-/* Switch from one thread to another. */
+/* Switch from one thread to another.  */
 
 void
 switch_to_thread (ptid_t ptid)
 {
+  /* Switch the program space as well, if we can infer it from the now
+     current thread.  Otherwise, it's up to the caller to select the
+     space it wants.  */
+  if (!ptid_equal (ptid, null_ptid))
+    {
+      struct inferior *inf;
+
+      inf = find_inferior_pid (ptid_get_pid (ptid));
+      gdb_assert (inf != NULL);
+      set_current_program_space (inf->pspace);
+      set_current_inferior (inf);
+    }
+
   if (ptid_equal (ptid, inferior_ptid))
     return;
 
   inferior_ptid = ptid;
   reinit_frame_cache ();
-  registers_changed ();
-  stop_pc = read_pc ();
+
+  /* We don't check for is_stopped, because we're called at times
+     while in the TARGET_RUNNING state, e.g., while handling an
+     internal event.  */
+  if (!ptid_equal (inferior_ptid, null_ptid)
+      && !is_exited (ptid)
+      && !is_executing (ptid))
+    stop_pc = regcache_read_pc (get_thread_regcache (ptid));
+  else
+    stop_pc = ~(CORE_ADDR) 0;
 }
 
 static void
 restore_current_thread (ptid_t ptid)
 {
-  if (!ptid_equal (ptid, inferior_ptid))
-    {
-      switch_to_thread (ptid);
-    }
+  switch_to_thread (ptid);
 }
 
 static void
-restore_selected_frame (struct frame_id a_frame_id)
+restore_selected_frame (struct frame_id a_frame_id, int frame_level)
 {
-  struct frame_info *selected_frame_info = NULL;
+  struct frame_info *frame = NULL;
+  int count;
+
+  /* This means there was no selected frame.  */
+  if (frame_level == -1)
+    {
+      select_frame (NULL);
+      return;
+    }
 
-  if (frame_id_eq (a_frame_id, null_frame_id))
-    return;        
+  gdb_assert (frame_level >= 0);
+
+  /* Restore by level first, check if the frame id is the same as
+     expected.  If that fails, try restoring by frame id.  If that
+     fails, nothing to do, just warn the user.  */
+
+  count = frame_level;
+  frame = find_relative_frame (get_current_frame (), &count);
+  if (count == 0
+      && frame != NULL
+      /* The frame ids must match - either both valid or both outer_frame_id.
+	 The latter case is not failsafe, but since it's highly unlikely
+	 the search by level finds the wrong frame, it's 99.9(9)% of
+	 the time (for all practical purposes) safe.  */
+      && frame_id_eq (get_frame_id (frame), a_frame_id))
+    {
+      /* Cool, all is fine.  */
+      select_frame (frame);
+      return;
+    }
+
+  frame = frame_find_by_id (a_frame_id);
+  if (frame != NULL)
+    {
+      /* Cool, refound it.  */
+      select_frame (frame);
+      return;
+    }
 
-  if ((selected_frame_info = frame_find_by_id (a_frame_id)) != NULL)
+  /* Nothing else to do, the frame layout really changed.  Select the
+     innermost stack frame.  */
+  select_frame (get_current_frame ());
+
+  /* Warn the user.  */
+  if (frame_level > 0 && !ui_out_is_mi_like_p (current_uiout))
     {
-      select_frame (selected_frame_info);
+      warning (_("Couldn't restore frame #%d in "
+		 "current thread.  Bottom (innermost) frame selected:"),
+	       frame_level);
+      /* For MI, we should probably have a notification about
+	 current frame change.  But this error is not very
+	 likely, so don't bother for now.  */
+      print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
     }
 }
 
@@ -556,26 +1090,115 @@ struct current_thread_cleanup
 {
   ptid_t inferior_ptid;
   struct frame_id selected_frame_id;
+  int selected_frame_level;
+  int was_stopped;
+  int inf_id;
+  int was_removable;
 };
 
 static void
 do_restore_current_thread_cleanup (void *arg)
+{
+  struct thread_info *tp;
+  struct current_thread_cleanup *old = arg;
+
+  tp = find_thread_ptid (old->inferior_ptid);
+
+  /* If the previously selected thread belonged to a process that has
+     in the mean time been deleted (due to normal exit, detach, etc.),
+     then don't revert back to it, but instead simply drop back to no
+     thread selected.  */
+  if (tp
+      && find_inferior_pid (ptid_get_pid (tp->ptid)) != NULL)
+    restore_current_thread (old->inferior_ptid);
+  else
+    {
+      restore_current_thread (null_ptid);
+      set_current_inferior (find_inferior_id (old->inf_id));
+    }
+
+  /* The running state of the originally selected thread may have
+     changed, so we have to recheck it here.  */
+  if (!ptid_equal (inferior_ptid, null_ptid)
+      && old->was_stopped
+      && is_stopped (inferior_ptid)
+      && target_has_registers
+      && target_has_stack
+      && target_has_memory)
+    restore_selected_frame (old->selected_frame_id,
+			    old->selected_frame_level);
+}
+
+static void
+restore_current_thread_cleanup_dtor (void *arg)
 {
   struct current_thread_cleanup *old = arg;
-  restore_current_thread (old->inferior_ptid);
-  restore_selected_frame (old->selected_frame_id);
+  struct thread_info *tp;
+  struct inferior *inf;
+
+  tp = find_thread_ptid (old->inferior_ptid);
+  if (tp)
+    tp->refcount--;
+  inf = find_inferior_id (old->inf_id);
+  if (inf != NULL)
+    inf->removable = old->was_removable;
   xfree (old);
 }
 
+/* Set the thread reference count.  */
+
+static void
+set_thread_refcount (void *data)
+{
+  int k;
+  struct thread_array_cleanup *ta_cleanup = data;
+
+  for (k = 0; k != ta_cleanup->count; k++)
+    ta_cleanup->tp_array[k]->refcount--;
+}
+
 struct cleanup *
-make_cleanup_restore_current_thread (ptid_t inferior_ptid, 
-                                     struct frame_id a_frame_id)
+make_cleanup_restore_current_thread (void)
 {
-  struct current_thread_cleanup *old
-    = xmalloc (sizeof (struct current_thread_cleanup));
+  struct thread_info *tp;
+  struct frame_info *frame;
+  struct current_thread_cleanup *old;
+
+  old = xmalloc (sizeof (struct current_thread_cleanup));
   old->inferior_ptid = inferior_ptid;
-  old->selected_frame_id = a_frame_id;
-  return make_cleanup (do_restore_current_thread_cleanup, old);
+  old->inf_id = current_inferior ()->num;
+  old->was_removable = current_inferior ()->removable;
+
+  if (!ptid_equal (inferior_ptid, null_ptid))
+    {
+      old->was_stopped = is_stopped (inferior_ptid);
+      if (old->was_stopped
+	  && target_has_registers
+	  && target_has_stack
+	  && target_has_memory)
+	{
+	  /* When processing internal events, there might not be a
+	     selected frame.  If we naively call get_selected_frame
+	     here, then we can end up reading debuginfo for the
+	     current frame, but we don't generally need the debuginfo
+	     at this point.  */
+	  frame = get_selected_frame_if_set ();
+	}
+      else
+	frame = NULL;
+
+      old->selected_frame_id = get_frame_id (frame);
+      old->selected_frame_level = frame_relative_level (frame);
+
+      tp = find_thread_ptid (inferior_ptid);
+      if (tp)
+	tp->refcount++;
+    }
+
+  current_inferior ()->removable = 0;
+
+  return make_cleanup_dtor (do_restore_current_thread_cleanup, old,
+			    restore_current_thread_cleanup_dtor);
 }
 
 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
@@ -584,67 +1207,75 @@ make_cleanup_restore_current_thread (ptid_t inferior_ptid,
 
    thread apply 1 2 7 4 backtrace       Apply backtrace cmd to threads 1,2,7,4
    thread apply 2-7 9 p foo(1)  Apply p foo(1) cmd to threads 2->7 & 9
-   thread apply all p x/i $pc   Apply x/i $pc cmd to all threads
- */
+   thread apply all p x/i $pc   Apply x/i $pc cmd to all threads.  */
 
 static void
 thread_apply_all_command (char *cmd, int from_tty)
 {
-  struct thread_info *tp;
   struct cleanup *old_chain;
-  struct cleanup *saved_cmd_cleanup_chain;
   char *saved_cmd;
-  struct frame_id saved_frame_id;
-  ptid_t current_ptid;
-  int thread_has_changed = 0;
+  int tc;
+  struct thread_array_cleanup ta_cleanup;
 
   if (cmd == NULL || *cmd == '\000')
     error (_("Please specify a command following the thread ID list"));
-  
-  current_ptid = inferior_ptid;
-  saved_frame_id = get_frame_id (get_selected_frame (NULL));
-  old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
 
-  /* It is safe to update the thread list now, before
-     traversing it for "thread apply all".  MVS */
-  target_find_new_threads ();
+  update_thread_list ();
+
+  old_chain = make_cleanup_restore_current_thread ();
 
   /* Save a copy of the command in case it is clobbered by
-     execute_command */
+     execute_command.  */
   saved_cmd = xstrdup (cmd);
-  saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
-  for (tp = thread_list; tp; tp = tp->next)
-    if (thread_alive (tp))
-      {
-	switch_to_thread (tp->ptid);
-	printf_filtered (_("\nThread %d (%s):\n"),
-			 tp->num, target_tid_to_str (inferior_ptid));
-	execute_command (cmd, from_tty);
-	strcpy (cmd, saved_cmd);	/* Restore exact command used previously */
-      }
+  make_cleanup (xfree, saved_cmd);
+  tc = thread_count ();
 
-  if (!ptid_equal (current_ptid, inferior_ptid))
-    thread_has_changed = 1;
+  if (tc)
+    {
+      struct thread_info **tp_array;
+      struct thread_info *tp;
+      int i = 0, k;
+
+      /* Save a copy of the thread_list in case we execute detach
+         command.  */
+      tp_array = xmalloc (sizeof (struct thread_info *) * tc);
+      make_cleanup (xfree, tp_array);
+      ta_cleanup.tp_array = tp_array;
+      ta_cleanup.count = tc;
+
+      ALL_THREADS (tp)
+        {
+          tp_array[i] = tp;
+          tp->refcount++;
+          i++;
+        }
+
+      make_cleanup (set_thread_refcount, &ta_cleanup);
+
+      for (k = 0; k != i; k++)
+        if (thread_alive (tp_array[k]))
+          {
+            switch_to_thread (tp_array[k]->ptid);
+            printf_filtered (_("\nThread %d (%s):\n"), 
+			     tp_array[k]->num,
+			     target_pid_to_str (inferior_ptid));
+            execute_command (cmd, from_tty);
+
+            /* Restore exact command used previously.  */
+            strcpy (cmd, saved_cmd);
+	  }
+    }
 
-  do_cleanups (saved_cmd_cleanup_chain);
   do_cleanups (old_chain);
-  /* Print stack frame only if we changed thread.  */
-  if (thread_has_changed)
-    print_stack_frame (get_current_frame (), 1, SRC_LINE);
-
 }
 
 static void
 thread_apply_command (char *tidlist, int from_tty)
 {
   char *cmd;
-  char *p;
   struct cleanup *old_chain;
-  struct cleanup *saved_cmd_cleanup_chain;
   char *saved_cmd;
-  struct frame_id saved_frame_id;
-  ptid_t current_ptid;
-  int thread_has_changed = 0;
+  struct get_number_or_range_state state;
 
   if (tidlist == NULL || *tidlist == '\000')
     error (_("Please specify a thread ID list"));
@@ -654,68 +1285,41 @@ thread_apply_command (char *tidlist, int from_tty)
   if (*cmd == '\000')
     error (_("Please specify a command following the thread ID list"));
 
-  current_ptid = inferior_ptid;
-  saved_frame_id = get_frame_id (get_selected_frame (NULL));
-  old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
-
   /* Save a copy of the command in case it is clobbered by
-     execute_command */
+     execute_command.  */
   saved_cmd = xstrdup (cmd);
-  saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
-  while (tidlist < cmd)
+  old_chain = make_cleanup (xfree, saved_cmd);
+
+  init_number_or_range (&state, tidlist);
+  while (!state.finished && state.string < cmd)
     {
       struct thread_info *tp;
-      int start, end;
+      int start;
 
-      start = strtol (tidlist, &p, 10);
-      if (p == tidlist)
-	error (_("Error parsing %s"), tidlist);
-      tidlist = p;
+      start = get_number_or_range (&state);
 
-      while (*tidlist == ' ' || *tidlist == '\t')
-	tidlist++;
+      make_cleanup_restore_current_thread ();
 
-      if (*tidlist == '-')	/* Got a range of IDs? */
-	{
-	  tidlist++;		/* Skip the - */
-	  end = strtol (tidlist, &p, 10);
-	  if (p == tidlist)
-	    error (_("Error parsing %s"), tidlist);
-	  tidlist = p;
-
-	  while (*tidlist == ' ' || *tidlist == '\t')
-	    tidlist++;
-	}
-      else
-	end = start;
+      tp = find_thread_id (start);
 
-      for (; start <= end; start++)
+      if (!tp)
+	warning (_("Unknown thread %d."), start);
+      else if (!thread_alive (tp))
+	warning (_("Thread %d has terminated."), start);
+      else
 	{
-	  tp = find_thread_id (start);
+	  switch_to_thread (tp->ptid);
 
-	  if (!tp)
-	    warning (_("Unknown thread %d."), start);
-	  else if (!thread_alive (tp))
-	    warning (_("Thread %d has terminated."), start);
-	  else
-	    {
-	      switch_to_thread (tp->ptid);
-	      printf_filtered (_("\nThread %d (%s):\n"), tp->num,
-			       target_tid_to_str (inferior_ptid));
-	      execute_command (cmd, from_tty);
-	      strcpy (cmd, saved_cmd);	/* Restore exact command used previously */
-	    }
+	  printf_filtered (_("\nThread %d (%s):\n"), tp->num,
+			   target_pid_to_str (inferior_ptid));
+	  execute_command (cmd, from_tty);
+
+	  /* Restore exact command used previously.  */
+	  strcpy (cmd, saved_cmd);
 	}
     }
 
-  if (!ptid_equal (current_ptid, inferior_ptid))
-    thread_has_changed = 1;
-
-  do_cleanups (saved_cmd_cleanup_chain);
   do_cleanups (old_chain);
-  /* Print stack frame only if we changed thread.  */
-  if (thread_has_changed)
-    print_stack_frame (get_current_frame (), 1, SRC_LINE);
 }
 
 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
@@ -726,17 +1330,97 @@ thread_command (char *tidstr, int from_tty)
 {
   if (!tidstr)
     {
-      /* Don't generate an error, just say which thread is current. */
+      if (ptid_equal (inferior_ptid, null_ptid))
+	error (_("No thread selected"));
+
       if (target_has_stack)
-	printf_filtered (_("[Current thread is %d (%s)]\n"),
-			 pid_to_thread_id (inferior_ptid),
-			 target_tid_to_str (inferior_ptid));
+	{
+	  if (is_exited (inferior_ptid))
+	    printf_filtered (_("[Current thread is %d (%s) (exited)]\n"),
+			     pid_to_thread_id (inferior_ptid),
+			     target_pid_to_str (inferior_ptid));
+	  else
+	    printf_filtered (_("[Current thread is %d (%s)]\n"),
+			     pid_to_thread_id (inferior_ptid),
+			     target_pid_to_str (inferior_ptid));
+	}
       else
 	error (_("No stack."));
       return;
     }
 
-  gdb_thread_select (uiout, tidstr, NULL);
+  gdb_thread_select (current_uiout, tidstr, NULL);
+}
+
+/* Implementation of `thread name'.  */
+
+static void
+thread_name_command (char *arg, int from_tty)
+{
+  struct thread_info *info;
+
+  if (ptid_equal (inferior_ptid, null_ptid))
+    error (_("No thread selected"));
+
+  arg = skip_spaces (arg);
+
+  info = inferior_thread ();
+  xfree (info->name);
+  info->name = arg ? xstrdup (arg) : NULL;
+}
+
+/* Find thread ids with a name, target pid, or extra info matching ARG.  */
+
+static void
+thread_find_command (char *arg, int from_tty)
+{
+  struct thread_info *tp;
+  char *tmp;
+  unsigned long match = 0;
+
+  if (arg == NULL || *arg == '\0')
+    error (_("Command requires an argument."));
+
+  tmp = re_comp (arg);
+  if (tmp != 0)
+    error (_("Invalid regexp (%s): %s"), tmp, arg);
+
+  update_thread_list ();
+  for (tp = thread_list; tp; tp = tp->next)
+    {
+      if (tp->name != NULL && re_exec (tp->name))
+	{
+	  printf_filtered (_("Thread %d has name '%s'\n"),
+			   tp->num, tp->name);
+	  match++;
+	}
+
+      tmp = target_thread_name (tp);
+      if (tmp != NULL && re_exec (tmp))
+	{
+	  printf_filtered (_("Thread %d has target name '%s'\n"),
+			   tp->num, tmp);
+	  match++;
+	}
+
+      tmp = target_pid_to_str (tp->ptid);
+      if (tmp != NULL && re_exec (tmp))
+	{
+	  printf_filtered (_("Thread %d has target id '%s'\n"),
+			   tp->num, tmp);
+	  match++;
+	}
+
+      tmp = target_extra_thread_info (tp);
+      if (tmp != NULL && re_exec (tmp))
+	{
+	  printf_filtered (_("Thread %d has extra info '%s'\n"),
+			   tp->num, tmp);
+	  match++;
+	}
+    }
+  if (!match)
+    printf_filtered (_("No threads match '%s'\n"), arg);
 }
 
 /* Print notices when new threads are attached and detached.  */
@@ -745,8 +1429,8 @@ static void
 show_print_thread_events (struct ui_file *file, int from_tty,
                           struct cmd_list_element *c, const char *value)
 {
-  fprintf_filtered (file, _("\
-Printing of thread events is %s.\n"),
+  fprintf_filtered (file,
+		    _("Printing of thread events is %s.\n"),
                     value);
 }
 
@@ -768,13 +1452,28 @@ do_captured_thread_select (struct ui_out *uiout, void *tidstr)
 
   switch_to_thread (tp->ptid);
 
+  annotate_thread_changed ();
+
   ui_out_text (uiout, "[Switching to thread ");
   ui_out_field_int (uiout, "new-thread-id", pid_to_thread_id (inferior_ptid));
   ui_out_text (uiout, " (");
-  ui_out_text (uiout, target_tid_to_str (inferior_ptid));
+  ui_out_text (uiout, target_pid_to_str (inferior_ptid));
   ui_out_text (uiout, ")]");
 
-  print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
+  /* Note that we can't reach this with an exited thread, due to the
+     thread_alive check above.  */
+  if (tp->state == THREAD_RUNNING)
+    ui_out_text (uiout, "(running)\n");
+  else
+    {
+      ui_out_text (uiout, "\n");
+      print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
+    }
+
+  /* Since the current thread may have changed, see if there is any
+     exited thread we can now delete.  */
+  prune_threads ();
+
   return GDB_RC_OK;
 }
 
@@ -787,16 +1486,48 @@ gdb_thread_select (struct ui_out *uiout, char *tidstr, char **error_message)
   return GDB_RC_OK;
 }
 
+void
+update_thread_list (void)
+{
+  prune_threads ();
+  target_find_new_threads ();
+}
+
+/* Return a new value for the selected thread's id.  Return a value of 0 if
+   no thread is selected, or no threads exist.  */
+
+static struct value *
+thread_id_make_value (struct gdbarch *gdbarch, struct internalvar *var,
+		      void *ignore)
+{
+  struct thread_info *tp = find_thread_ptid (inferior_ptid);
+
+  return value_from_longest (builtin_type (gdbarch)->builtin_int,
+			     (tp ? tp->num : 0));
+}
+
 /* Commands with a prefix of `thread'.  */
 struct cmd_list_element *thread_cmd_list = NULL;
 
+/* Implementation of `thread' variable.  */
+
+static const struct internalvar_funcs thread_funcs =
+{
+  thread_id_make_value,
+  NULL,
+  NULL
+};
+
 void
 _initialize_thread (void)
 {
   static struct cmd_list_element *thread_apply_list = NULL;
 
-  add_info ("threads", info_threads_command,
-	    _("IDs of currently known threads."));
+  add_info ("threads", info_threads_command, 
+	    _("Display currently known threads.\n\
+Usage: info threads [ID]...\n\
+Optional arguments are thread IDs with spaces between.\n\
+If no arguments, all threads are displayed."));
 
   add_prefix_cmd ("thread", class_run, thread_command, _("\
 Use this command to switch between threads.\n\
@@ -810,14 +1541,27 @@ The new thread ID must be currently known."),
   add_cmd ("all", class_run, thread_apply_all_command,
 	   _("Apply a command to all threads."), &thread_apply_list);
 
+  add_cmd ("name", class_run, thread_name_command,
+	   _("Set the current thread's name.\n\
+Usage: thread name [NAME]\n\
+If NAME is not given, then any existing name is removed."), &thread_cmd_list);
+
+  add_cmd ("find", class_run, thread_find_command, _("\
+Find threads that match a regular expression.\n\
+Usage: thread find REGEXP\n\
+Will display thread ids whose name, target ID, or extra info matches REGEXP."),
+	   &thread_cmd_list);
+
   if (!xdb_commands)
     add_com_alias ("t", "thread", class_run, 1);
 
   add_setshow_boolean_cmd ("thread-events", no_class,
          &print_thread_events, _("\
-Set printing of thread events (e.g., thread start and exit)."), _("\
-Show printing of thread events (e.g., thread start and exit)."), NULL,
+Set printing of thread events (such as thread start and exit)."), _("\
+Show printing of thread events (such as thread start and exit)."), NULL,
          NULL,
          show_print_thread_events,
          &setprintlist, &showprintlist);
+
+  create_internalvar_type_lazy ("_thread", &thread_funcs, NULL);
 }