[wesnoth_addon_manager] Speedup writing files to disk *a lot* :)

data/tools/wesnoth/campaignserver_client.py

@@ -180,17 +180,17 @@ class CampaignClient:
         return data
 
     def unescape(self, data):
+        data2 = bytearray()
         # 01 is used as escape character
-        data2 = b""
-        escape = False
-        for c in data:
-            if escape:
-                data2 += bytes([c - 1])
-                escape = False
-            elif c == 1:
-                escape = True
-            else:
-                data2 += bytes([c])
+        pos = 0
+        while True:
+            i = data.find(b"\x01", pos)
+            if i < 0:
+                break
+            data2 += data[pos:i]
+            data2 += bytes([data[i + 1] - 1])
+            pos = i + 2
+        data2 += data[pos:]
         return data2
 
     def decode_WML(self, data):