new function ffmpeg shell

plugins/shell.py

@@ -0,0 +1,35 @@
+import threading
+import copy
+import os
+import subprocess
+from mswp import Datapack
+from forwarder import receive_queues, send_queue
+from config import msw_queue
+from config import dprint as print
+receive_queue = receive_queues[__name__]
+
+
+def main():
+    while True:
+        dp = receive_queue.get()
+        command = dp.body.decode()
+        try:
+            result = subprocess.check_output(command, shell=True)
+        except Exception as e:
+            result = 'Command %s error, %s: %s' % (command, type(e), str(e))
+            result = result.encode()
+        
+        ndp = dp.reply()
+        ndp.body = try_decode_and_encode(result)
+        send_queue.put(ndp)
+
+
+def try_decode_and_encode(data):
+    try:
+        return data.decode('gb2312').encode()
+    except:
+        return data.decode('utf-8').encode()
+
+thread = threading.Thread(target=main, args=(), daemon=True)
+thread.start()
+