From 4a1e5090ecbf0bb4003b658d40278afe79a2172f Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Sat, 9 Mar 2019 11:12:29 +1100
Subject: [PATCH] relay: allow for multiple input devices

---
 quimby-relay                  | 68 ++++++++++++++++++++++-------------
 systemd/system/quimby.service |  2 +-
 2 files changed, 44 insertions(+), 26 deletions(-)

diff --git a/quimby-relay b/quimby-relay
index 0e29ca0..a48372e 100755
--- a/quimby-relay
+++ b/quimby-relay
@@ -4,6 +4,7 @@ import evdev
 import argparse
 import os
 import sys
+import selectors
 
 scan_to_hid = {
     # Reserved: 0
@@ -178,52 +179,69 @@ modifiers = {
 }
 
 
+class forwarder(object):
+    def __init__(self, dst):
+        self.modifier_state = 0
+        self.keys_down = set()
+        self.dst = dst
 
-if __name__ == '__main__':
-    parser = argparse.ArgumentParser(description='Forward input events to a USB descriptor')
-    parser.add_argument('input', type=str, help='The source evdev device')
-    parser.add_argument('output', type=str, help='The output HID device')
-
-    args = parser.parse_args()
-
-    dst = os.open(args.output, os.O_WRONLY)
-    src = evdev.InputDevice(args.input)
-    src.grab()
-
-    modifier_state = 0
-    keys_down = set()
-
-    for event in src.read_loop():
+    def __call__(self, event):
         if event.type != evdev.ecodes.EV_KEY:
-            continue
+            print("Not a key event", event)
+            return
 
         data = evdev.categorize(event)
 
         modifier = modifiers.get(data.scancode, None)
         if modifier:
             if data.keystate == data.key_down:
-                modifier_state |= modifier
+                self.modifier_state |= modifier
             if data.keystate == data.key_up:
-                modifier_state &= ~modifier
+                self.modifier_state &= ~modifier
         else:
             code = scan_to_hid.get(data.scancode, None)
             if code is None:
                 print("Ignoring unknown key", data)
-                continue
+                return
 
             if data.keystate == data.key_down:
-                if len(keys_down) >= 6:
+                if len(self.keys_down) >= 6:
                     print("Ignoring key due to rollover")
-                    continue
-                keys_down.add(code)
+                    return
+                self.keys_down.add(code)
 
             if data.keystate == data.key_up:
-                keys_down.remove(code)
+                self.keys_down.remove(code)
 
         # Build the packet
-        packet = [modifier_state, 0] + [k for k in keys_down]
+        packet = [self.modifier_state, 0] + [k for k in self.keys_down]
         packet += [0] * (8 - len(packet))
 
         assert(len(packet) == 8)
 
-        os.write(dst, bytes(packet))
+        print(bytes(packet))
+        os.write(self.dst, bytes(packet))
+
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Forward input events to a USB descriptor')
+    parser.add_argument('-i', '--input', type=str, action='append', help='A source evdev device')
+    parser.add_argument('-o', '--output', type=str, help='The output HID device')
+
+    args = parser.parse_args()
+
+    fwd = forwarder(os.open(args.output, os.O_WRONLY))
+    src = [evdev.InputDevice(i) for i in args.input]
+
+    selector = selectors.DefaultSelector()
+    for i in src:
+        i.grab()
+        selector.register(i, selectors.EVENT_READ)
+
+    print("Waiting for events")
+    while True:
+        for key, mask in selector.select():
+            device = key.fileobj
+            for event in device.read():
+                fwd(event)
diff --git a/systemd/system/quimby.service b/systemd/system/quimby.service
index 0d4f5a9..9db745c 100644
--- a/systemd/system/quimby.service
+++ b/systemd/system/quimby.service
@@ -5,6 +5,6 @@ Requires=bluetooth.service
 [Service]
 Type=simple
 ExecStartPre=/usr/local/bin/quimby-setup quimby
-ExecStart=/usr/local/bin/quimby-relay /dev/input/event0 /dev/hidg0
+ExecStart=/usr/local/bin/quimby-relay --input /dev/input/event0 --output /dev/hidg0
 ExecStop=/usr/local/bin/quimby-cleanup quimby