motion_queuing: Track all trapqs and globally flush all trapqs

Add an allocate_trapq() helper function to facilitate the creation of
a low-level C trapq object.  Track all trapq objects and clear history
on them globally when the main motion queues are flushed.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/extras/motion_queuing.py

@@ -4,16 +4,36 @@
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import logging
+import chelper
 
 class PrinterMotionQueuing:
     def __init__(self, config):
         self.printer = config.get_printer()
         self.steppers = []
+        self.trapqs = []
+        ffi_main, ffi_lib = chelper.get_ffi()
+        self.trapq_finalize_moves = ffi_lib.trapq_finalize_moves
+    def allocate_trapq(self):
+        ffi_main, ffi_lib = chelper.get_ffi()
+        trapq = ffi_main.gc(ffi_lib.trapq_alloc(), ffi_lib.trapq_free)
+        self.trapqs.append(trapq)
+        return trapq
     def register_stepper(self, config, stepper):
         self.steppers.append(stepper)
     def flush_motion_queues(self, must_flush_time, max_step_gen_time):
         for stepper in self.steppers:
             stepper.generate_steps(max_step_gen_time)
+    def clean_motion_queues(self, trapq_free_time, clear_history_time):
+        for trapq in self.trapqs:
+            self.trapq_finalize_moves(trapq, trapq_free_time,
+                                      clear_history_time)
+    def wipe_trapq(self, trapq):
+        # Expire any remaining movement in the trapq (force to history list)
+        NEVER = 9999999999999999.
+        self.trapq_finalize_moves(trapq, NEVER, 0.)
+    def lookup_trapq_append(self):
+        ffi_main, ffi_lib = chelper.get_ffi()
+        return ffi_lib.trapq_append
 
 def load_config(config):
     return PrinterMotionQueuing(config)