gdbserver: introduce scoped_restore_current_thread and switch_to_thread

Introduce a class for restoring the current thread and a function to
switch to the given thread.  This is a preparation for a refactoring
that aims to remove direct assignments to 'current_thread'.

1 files changed, 22 insertions, 0 deletions

diff --git a/gdbserver/gdbthread.h b/gdbserver/gdbthread.h
index 7c293b1f89d..315a4da5167 100644
--- a/gdbserver/gdbthread.h
+++ b/gdbserver/gdbthread.h
@@ -233,4 +233,26 @@ lwpid_of (const thread_info *thread)
   return thread->id.lwp ();
 }
 
+/* Switch the current thread.  */
+
+void switch_to_thread (thread_info *thread);
+
+/* Save/restore current thread.  */
+
+class scoped_restore_current_thread
+{
+public:
+  scoped_restore_current_thread ();
+  ~scoped_restore_current_thread ();
+
+  DISABLE_COPY_AND_ASSIGN (scoped_restore_current_thread);
+
+  /* Cancel restoring on scope exit.  */
+  void dont_restore () { m_dont_restore = true; }
+
+private:
+  bool m_dont_restore = false;
+  thread_info *m_thread;
+};
+
 #endif /* GDBSERVER_GDBTHREAD_H */