ask whether to use single-device or parallel mode

1 files changed, 22 insertions, 3 deletions

diff --git a/soas-assimilator.py b/soas-assimilator.py
index 48ddeca..6a8a74e 100755
--- a/soas-assimilator.py
+++ b/soas-assimilator.py
@@ -269,14 +269,14 @@ class WriteQThread (threading.Thread) :
 
 class tDeviceListener (object) :
 
-  def __init__(self, image_dir, status_cb) :
+  def __init__(self, image_dir, status_cb, use_parallel) :
     self.mode = 'read'
     self.image_dir = image_dir
     self.status_cb = status_cb
     self._images_dict = {}
     self._images_flat = []
     self._images_lastupdate = 0
-    self._use_write_q = True
+    self._use_write_q = not use_parallel
     self._write_q = []
     self._write_q_cond = threading.Condition()
     self.bus = dbus.Bus(dbus.Bus.TYPE_SYSTEM)
@@ -396,7 +396,8 @@ class tApp (object) :
   def __init__(self) :
     self._imageDir = self._chooseImageDir()
     self._devStatus = {}
-    self._deviceListener = tDeviceListener(self._imageDir, self._updateStatus)
+    parallel = self._askParallel()
+    self._deviceListener = tDeviceListener(self._imageDir, self._updateStatus, parallel)
     if self._askReadImage() :
       self._win = tReadWindow()
       self._win.writeButton.connect("clicked", self._showWriteWindow)
@@ -472,6 +473,24 @@ class tApp (object) :
     askDialog.destroy()
     return (res == gtk.RESPONSE_OK)
 
+  def _askParallel(self) :
+    """
+    Ask the user whether to restrict writing to a single device at a time or
+    write in parallel. Returns True for the latter, False otherwise.
+    """
+    askDialog = gtk.MessageDialog(type=gtk.MESSAGE_QUESTION,
+      buttons=gtk.BUTTONS_NONE,
+      message_format="\n".join([x.strip() for x in """
+        If you are using a slow (i.e. 12Mbps / FullSpeed) hub or your system is having trouble with USB, it might make
+        sense to write access a single device at a time. Usually parallel mode is much faster and thus recommended, though.
+        """.split("\n")]))
+
+    askDialog.add_buttons("Parallel mode", gtk.RESPONSE_OK, "Single device mode", gtk.RESPONSE_CANCEL)
+    askDialog.set_title("Read images first?")
+    res = askDialog.run()
+    askDialog.destroy()
+    return (res == gtk.RESPONSE_OK)
+
   def run(self) :
     gtk.main()