Introduce fetch_pending_stop

This introduces a new "fetch_pending_stop" function and changes gdb to
use it.  This function removes the first matching pending stop from
the list of such stops.

gdb/ChangeLog
2020-04-08  Tom Tromey  <tromey@adacore.com>

	* windows-nat.c (get_windows_debug_event): Use
	fetch_pending_stop.
	* nat/windows-nat.h (fetch_pending_stop): Declare.
	* nat/windows-nat.c (fetch_pending_stop): New function.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 3929faf089edfad4435f11ee96ca3fffa46112d0..738c6c2d779e1672fab7b067dd98460e3925ee84 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2020-04-08  Tom Tromey  <tromey@adacore.com>
+
+       * windows-nat.c (get_windows_debug_event): Use
+       fetch_pending_stop.
+       * nat/windows-nat.h (fetch_pending_stop): Declare.
+       * nat/windows-nat.c (fetch_pending_stop): New function.
+
 2020-04-08  Tom Tromey  <tromey@adacore.com>
 
        * windows-nat.c (windows_continue): Use matching_pending_stop and

diff --git a/gdb/nat/windows-nat.c b/gdb/nat/windows-nat.c
index 2c2454b6f6f7768e86e9836d4ca5b2476e3ce7ec..823471eb4dabe18872a4142a98f3821c7e56e8ed 100644 (file)
--- a/gdb/nat/windows-nat.c
+++ b/gdb/nat/windows-nat.c
@@ -343,6 +343,34 @@ matching_pending_stop (bool debug_events)
 
 /* See nat/windows-nat.h.  */
 
+gdb::optional<pending_stop>
+fetch_pending_stop (bool debug_events)
+{
+  gdb::optional<pending_stop> result;
+  for (auto iter = pending_stops.begin ();
+       iter != pending_stops.end ();
+       ++iter)
+    {
+      if (desired_stop_thread_id == -1
+         || desired_stop_thread_id == iter->thread_id)
+       {
+         result = *iter;
+         current_event = iter->event;
+
+         DEBUG_EVENTS (("get_windows_debug_event - "
+                        "pending stop found in 0x%x (desired=0x%x)\n",
+                        iter->thread_id, desired_stop_thread_id));
+
+         pending_stops.erase (iter);
+         break;
+       }
+    }
+
+  return result;
+}
+
+/* See nat/windows-nat.h.  */
+
 BOOL
 continue_last_debug_event (DWORD continue_status, bool debug_events)
 {

diff --git a/gdb/nat/windows-nat.h b/gdb/nat/windows-nat.h
index 0e9316577ba9efd267d6a075066c025f46bfc1e4..68b72d4bbd205f01abaadaee585e758725060817 100644 (file)
--- a/gdb/nat/windows-nat.h
+++ b/gdb/nat/windows-nat.h
@@ -22,6 +22,7 @@
 #include <windows.h>
 #include <vector>
 
+#include "gdbsupport/gdb_optional.h"
 #include "target/waitstatus.h"
 
 namespace windows_nat
@@ -231,6 +232,12 @@ extern handle_exception_result handle_exception
 
 extern bool matching_pending_stop (bool debug_events);
 
+/* See if a pending stop matches DESIRED_STOP_THREAD_ID.  If so,
+   remove it from the list of pending stops, set 'current_event', and
+   return it.  Otherwise, return an empty optional.  */
+
+extern gdb::optional<pending_stop> fetch_pending_stop (bool debug_events);
+
 /* A simple wrapper for ContinueDebugEvent that continues the last
    waited-for event.  If DEBUG_EVENTS is true, logging will be
    enabled.  */

diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index d04dc06f3bf7cd7bfd31f0addff2827f0af05729..2ee7a2412a9b1dd5e93756871e40bcf185c655f6 100644 (file)
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1522,29 +1522,18 @@ windows_nat_target::get_windows_debug_event (int pid,
   /* If there is a relevant pending stop, report it now.  See the
      comment by the definition of "pending_stops" for details on why
      this is needed.  */
-  for (auto iter = pending_stops.begin ();
-       iter != pending_stops.end ();
-       ++iter)
+  gdb::optional<pending_stop> stop = fetch_pending_stop (debug_events);
+  if (stop.has_value ())
     {
-      if (desired_stop_thread_id == -1
-         || desired_stop_thread_id == iter->thread_id)
-       {
-         thread_id = iter->thread_id;
-         *ourstatus = iter->status;
-         current_event = iter->event;
-
-         inferior_ptid = ptid_t (current_event.dwProcessId, thread_id, 0);
-         current_windows_thread = thread_rec (inferior_ptid,
-                                              INVALIDATE_CONTEXT);
-         current_windows_thread->reload_context = 1;
+      thread_id = stop->thread_id;
+      *ourstatus = stop->status;
 
-         DEBUG_EVENTS (("get_windows_debug_event - "
-                        "pending stop found in 0x%x (desired=0x%x)\n",
-                        thread_id, desired_stop_thread_id));
+      inferior_ptid = ptid_t (current_event.dwProcessId, thread_id, 0);
+      current_windows_thread = thread_rec (inferior_ptid,
+                                          INVALIDATE_CONTEXT);
+      current_windows_thread->reload_context = 1;
 
-         pending_stops.erase (iter);
-         return thread_id;
-       }
+      return thread_id;
     }
 
   last_sig = GDB_SIGNAL_0;