From 18ca465f9489f135a3f646f3484af6e569007012 Mon Sep 17 00:00:00 2001
From: Eugene Crosser <crosser@average.org>
Date: Fri, 22 Apr 2022 22:59:24 +0200
Subject: [PATCH] introduce `class_by_prefix()`

---
 gps303/common.py      |  5 +++--
 gps303/gps303proto.py | 10 ++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/gps303/common.py b/gps303/common.py
index 44c301d..6e4a2f3 100644
--- a/gps303/common.py
+++ b/gps303/common.py
@@ -10,8 +10,9 @@ PORT = 4303
 DBFN = "/var/lib/gps303/gps303.sqlite"
 
 
-def init(log):
-    opts, _ = getopt(argv[1:], "c:d")
+def init(log, opts=None):
+    if opts is None:
+        opts, _ = getopt(argv[1:], "c:d")
     opts = dict(opts)
     conf = readconfig(opts["-c"] if "-c" in opts else CONF)
     if stdout.isatty():
diff --git a/gps303/gps303proto.py b/gps303/gps303proto.py
index acfaea6..cc4ab3f 100755
--- a/gps303/gps303proto.py
+++ b/gps303/gps303proto.py
@@ -21,6 +21,7 @@ from logging import getLogger
 from struct import pack, unpack
 
 __all__ = (
+    "class_by_prefix",
     "handle_packet",
     "inline_response",
     "make_object",
@@ -536,6 +537,15 @@ if True:  # just to indent the code, sorry!
             PROTOS[cls.__name__] = cls.PROTO
 
 
+def class_by_prefix(prefix):
+    lst = [(name, proto) for name, proto in PROTOS.items()
+            if name.upper().startswith(prefix.upper())]
+    if len(lst) != 1:
+        return lst
+    _, proto = lst[0]
+    return CLASSES[proto]
+
+
 def proto_by_name(name):
     return PROTOS.get(name, -1)
 
-- 
2.43.0