[lldb] Fix python errors in gdbremote.py

[ddcc]

Summary

Fix exceptions encountered while debugging gdb protocol

[kastiglione]

lldb/examples/python/gdbremote.py

1224–1225

I don't know this tool, but should it print the original json (rsp) if there's an issue when decoding the json? Or should it print a message saying invalid json was given?

[ddcc]

lldb/examples/python/gdbremote.py

1224–1225

The contents of each packet are already printed earlier, this change only affects the "jThreadsInfo" message which is supposed to return a JSON response. But servers are allowed to return an empty response if they don't support a protocol message, which will fail to decode as valid JSON.

[kastiglione]

other than the comment about the json, looks all good to me!

lldb/examples/python/gdbremote.py

1224–1225

thanks for the explanation. My only suggestion is to handle that case explicitly, by checking that the response is not empty before decoding.

lldb/examples/python/gdbremote.py

def stop_gdb_log(debugger, command, result, dict):
     parser.add_option(
         '-v',
         '--verbose',
         action='store_true',
         dest='verbose',
         help='display verbose debug info',
         default=False)
     parser.add_option(
+        '--plot',
+        action='store_true',
+        dest='plot',
+        help='plot packet latencies by packet type',
+        default=False)
+    parser.add_option(
         '-q',
         '--quiet',
         action='store_true',
         dest='quiet',
         help='display verbose debug info',
         default=False)
     parser.add_option(
         '-C',
def get_key_value_pairs(self):
         if ';' in self.str:
             key_value_pairs = self.str.split(';')
             for key_value_pair in key_value_pairs:
                 if len(key_value_pair):
                     kvp.append(key_value_pair.split(':', 1))
         return kvp
 
     def split(self, ch):
-        return string.split(self.str, ch)
+        return self.str.split(ch)
 
     def split_hex(self, ch, byte_order):
         hex_values = list()
-        strings = string.split(self.str, ch)
+        strings = self.str.split(ch)
         for str in strings:
             hex_values.append(Packet(str).get_hex_uint(byte_order))
         return hex_values
 
     def __str__(self):
         return self.str
 
     def __len__(self):
elif rsp:
         if rsp[0] == 'O':
             print("stdout: %s" % (rsp))
             return
     else:
         print("not supported (cmd = '%s', args = '%s', rsp = '%s')" % (cmd, cmd_args, rsp))
 
 
 def cmd_vAttach(options, cmd, args):
-    (extra_command, args) = string.split(args, ';')
+    (extra_command, args) = args.split(';')
     if extra_command:
         print("%s%s(%s)" % (cmd, extra_command, args))
     else:
         print("attach(pid = %u)" % int(args, 16))
     return False
 
 
 def cmd_qRegisterInfo(options, cmd, args):
if have_escapes:
         # print 'escape_char for "%s" = %c' % (s[index:index+2], escape_char)
         return normal_s + escape_char + decode_packet(s, index + 2)
     else:
         return normal_s
 
 
 def rsp_json(options, cmd, cmd_args, rsp):
     print('%s() reply:' % (cmd))
+    if not rsp:
+        return
+    try:
         json_tree = json.loads(rsp)
         print(json.dumps(json_tree, indent=4, separators=(',', ': ')))
-
+    except json.JSONDecodeError:
+        return
 
 def rsp_jGetLoadedDynamicLibrariesInfos(options, cmd, cmd_args, rsp):
     if cmd_args:
         rsp_json(options, cmd, cmd_args, rsp)
     else:
         rsp_ok_means_supported(options, cmd, cmd_args, rsp)
 
 gdb_remote_commands = {
if packet_total_times:
             for item in res:
                 packet_total_time = packet_total_times[item]
                 packet_percent = (
                     packet_total_time / total_packet_time) * 100.0
                 packet_count = packet_counts[item]
                 print("  %24s %11.6f  %5.2f%% %6d %9.6f" % (
                         item, packet_total_time, packet_percent, packet_count,
                         float(packet_total_time) / float(packet_count)))
-        if options.plot:
+        if options and options.plot:
             plot_latencies(packet_times)
 
 if __name__ == '__main__':
     usage = "usage: gdbremote [options]"
     description = '''The command disassembles a GDB remote packet log.'''
     parser = optparse.OptionParser(
         description=description,
         prog='gdbremote',
         usage=usage)
     parser.add_option(
         '-v',
         '--verbose',
         action='store_true',
         dest='verbose',
         help='display verbose debug info',
         default=False)
     parser.add_option(
-        '--plot',
-        action='store_true',
-        dest='plot',
-        help='plot packet latencies by packet type',
-        default=False)
-    parser.add_option(
         '-q',
         '--quiet',
         action='store_true',
         dest='quiet',
         help='display verbose debug info',
         default=False)
     parser.add_option(
         '-C',