From a0829c63ded2b039e4aa0cc2ba5b5ca343a8ff82 Mon Sep 17 00:00:00 2001
From: Kevin O'Connor <kevin@koconnor.net>
Date: Mon, 28 Nov 2016 14:52:22 -0500
Subject: [PATCH] serialhdl: Make SerialReader.send_with_response() blocking

Use the greenlet mechanism to wait for the response directly in the
send_with_response() method.  This simplifies the calling code.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
---
 klippy/mcu.py       | 53 +++++++++++++++------------------------------
 klippy/serialhdl.py | 27 ++++++++++++++---------
 2 files changed, 35 insertions(+), 45 deletions(-)

diff --git a/klippy/mcu.py b/klippy/mcu.py
index 11581f55..a665ad32 100644
--- a/klippy/mcu.py
+++ b/klippy/mcu.py
@@ -337,10 +337,6 @@ class MCU:
         self.serial.dump_debug()
         self._printer.shutdown()
     # Connection phase
-    def _init_steppersync(self, count):
-        stepqueues = tuple(s._stepqueue for s in self._steppers)
-        self._steppersync = self.ffi_lib.steppersync_alloc(
-            self.serial.serialqueue, stepqueues, len(stepqueues), count)
     def connect(self):
         if not self._is_fileoutput:
             self.serial.connect()
@@ -351,13 +347,6 @@ class MCU:
     def connect_file(self, debugoutput, dictionary, pace=False):
         self._is_fileoutput = True
         self.serial.connect_file(debugoutput, dictionary)
-        def dummy_send_config():
-            for c in self._config_cmds:
-                self.send(self.create_command(c))
-            self._init_steppersync(500)
-            for cb in self._init_callbacks:
-                cb()
-        self._send_config = dummy_send_config
         if not pace:
             def dummy_set_print_start_time(eventtime):
                 pass
@@ -416,31 +405,25 @@ class MCU:
         self._send_config()
     def _send_config(self):
         msg = self.create_command("get_config")
-        config_params = {}
-        sent_config = False
-        def handle_get_config(params):
-            config_params.update(params)
-            return True
-        while 1:
-            self.serial.send_with_response(msg, handle_get_config, 'config')
-            while 1:
-                is_config = config_params.get('is_config')
-                if is_config is not None and (not sent_config or is_config):
-                    break
-                self._printer.reactor.pause(time.time() + 0.05)
-            if not is_config:
-                # Send config commands
-                for c in self._config_cmds:
-                    self.send(self.create_command(c))
-                config_params.clear()
-                sent_config = True
-                continue
-            if self._config_crc != config_params['crc']:
-                logging.error("Printer CRC does not match config")
-                sys.exit(1)
-            break
+        if self._is_fileoutput:
+            config_params = {
+                'is_config': 0, 'move_count': 500, 'crc': self._config_crc}
+        else:
+            config_params = self.serial.send_with_response(msg, 'config')
+        if not config_params['is_config']:
+            # Send config commands
+            for c in self._config_cmds:
+                self.send(self.create_command(c))
+            if not self._is_fileoutput:
+                config_params = self.serial.send_with_response(msg, 'config')
+        if self._config_crc != config_params['crc']:
+            logging.error("Printer CRC does not match config")
+            sys.exit(1)
         logging.info("Configured")
-        self._init_steppersync(config_params['move_count'])
+        stepqueues = tuple(s._stepqueue for s in self._steppers)
+        self._steppersync = self.ffi_lib.steppersync_alloc(
+            self.serial.serialqueue, stepqueues, len(stepqueues),
+            config_params['move_count'])
         for cb in self._init_callbacks:
             cb()
     # Config creation helpers
diff --git a/klippy/serialhdl.py b/klippy/serialhdl.py
index 09b775cc..a0b3a4ed 100644
--- a/klippy/serialhdl.py
+++ b/klippy/serialhdl.py
@@ -146,8 +146,9 @@ class SerialReader:
     def encode_and_send(self, data, minclock, reqclock, cq):
         self.ffi_lib.serialqueue_encode_and_send(
             self.serialqueue, cq, data, len(data), minclock, reqclock)
-    def send_with_response(self, cmd, callback, name):
-        SerialRetryCommand(self, cmd, callback, name)
+    def send_with_response(self, cmd, name):
+        src = SerialRetryCommand(self, cmd, name)
+        return src.get_response()
     def send_flush(self):
         self.ffi_lib.serialqueue_flush_ready(self.serialqueue)
     def alloc_command_queue(self):
@@ -207,25 +208,31 @@ class SerialReader:
 # Class to retry sending of a query command until a given response is received
 class SerialRetryCommand:
     RETRY_TIME = 0.500
-    def __init__(self, serial, cmd, callback, name):
+    def __init__(self, serial, cmd, name):
         self.serial = serial
         self.cmd = cmd
-        self.callback = callback
         self.name = name
+        self.response = None
+        self.min_query_time = time.time()
         self.serial.register_callback(self.handle_callback, self.name)
         self.send_timer = self.serial.reactor.register_timer(
             self.send_event, self.serial.reactor.NOW)
     def send_event(self, eventtime):
-        if self.callback is None:
-            self.serial.reactor.unregister_timer(self.send_timer)
+        if self.response is not None:
             return self.serial.reactor.NEVER
         self.serial.send(self.cmd)
         return eventtime + self.RETRY_TIME
     def handle_callback(self, params):
-        done = self.callback(params)
-        if done:
-            self.serial.unregister_callback(self.name)
-            self.callback = None
+        last_sent_time = params['#sent_time']
+        if last_sent_time >= self.min_query_time:
+            self.response = params
+    def get_response(self):
+        eventtime = time.time()
+        while self.response is None:
+            eventtime = self.serial.reactor.pause(eventtime + 0.05)
+        self.serial.unregister_callback(self.name)
+        self.serial.reactor.unregister_timer(self.send_timer)
+        return self.response
 
 # Code to start communication and download message type dictionary
 class SerialBootStrap: