klipper-dgus/klippy/msgproto.py

437 lines
15 KiB
Python

# Protocol definitions for firmware communication
#
# Copyright (C) 2016-2021 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import json, zlib, logging
DefaultMessages = {
"identify_response offset=%u data=%.*s": 0,
"identify offset=%u count=%c": 1,
}
MESSAGE_MIN = 5
MESSAGE_MAX = 64
MESSAGE_HEADER_SIZE = 2
MESSAGE_TRAILER_SIZE = 3
MESSAGE_POS_LEN = 0
MESSAGE_POS_SEQ = 1
MESSAGE_TRAILER_CRC = 3
MESSAGE_TRAILER_SYNC = 1
MESSAGE_PAYLOAD_MAX = MESSAGE_MAX - MESSAGE_MIN
MESSAGE_SEQ_MASK = 0x0f
MESSAGE_DEST = 0x10
MESSAGE_SYNC = '\x7E'
class error(Exception):
pass
def crc16_ccitt(buf):
crc = 0xffff
for data in buf:
data = ord(data)
data ^= crc & 0xff
data ^= (data & 0x0f) << 4
crc = ((data << 8) | (crc >> 8)) ^ (data >> 4) ^ (data << 3)
crc = chr(crc >> 8) + chr(crc & 0xff)
return crc
class PT_uint32:
is_int = True
is_dynamic_string = False
max_length = 5
signed = False
def encode(self, out, v):
if v >= 0xc000000 or v < -0x4000000: out.append((v>>28) & 0x7f | 0x80)
if v >= 0x180000 or v < -0x80000: out.append((v>>21) & 0x7f | 0x80)
if v >= 0x3000 or v < -0x1000: out.append((v>>14) & 0x7f | 0x80)
if v >= 0x60 or v < -0x20: out.append((v>>7) & 0x7f | 0x80)
out.append(v & 0x7f)
def parse(self, s, pos):
c = s[pos]
pos += 1
v = c & 0x7f
if (c & 0x60) == 0x60:
v |= -0x20
while c & 0x80:
c = s[pos]
pos += 1
v = (v<<7) | (c & 0x7f)
if not self.signed:
v = int(v & 0xffffffff)
return v, pos
class PT_int32(PT_uint32):
signed = True
class PT_uint16(PT_uint32):
max_length = 3
class PT_int16(PT_int32):
signed = True
max_length = 3
class PT_byte(PT_uint32):
max_length = 2
class PT_string:
is_int = False
is_dynamic_string = True
max_length = 64
def encode(self, out, v):
out.append(len(v))
out.extend(bytearray(v))
def parse(self, s, pos):
l = s[pos]
return bytes(bytearray(s[pos+1:pos+l+1])), pos+l+1
class PT_progmem_buffer(PT_string):
pass
class PT_buffer(PT_string):
pass
class enumeration_error(error):
def __init__(self, enum_name, value):
self.enum_name = enum_name
self.value = value
error.__init__(self, "Unknown value '%s' in enumeration '%s'"
% (value, enum_name))
def get_enum_params(self):
return self.enum_name, self.value
class Enumeration:
is_int = False
is_dynamic_string = False
def __init__(self, pt, enum_name, enums):
self.pt = pt
self.max_length = pt.max_length
self.enum_name = enum_name
self.enums = enums
self.reverse_enums = {v: k for k, v in enums.items()}
def encode(self, out, v):
tv = self.enums.get(v)
if tv is None:
raise enumeration_error(self.enum_name, v)
self.pt.encode(out, tv)
def parse(self, s, pos):
v, pos = self.pt.parse(s, pos)
tv = self.reverse_enums.get(v)
if tv is None:
tv = "?%d" % (v,)
return tv, pos
MessageTypes = {
'%u': PT_uint32(), '%i': PT_int32(),
'%hu': PT_uint16(), '%hi': PT_int16(),
'%c': PT_byte(),
'%s': PT_string(), '%.*s': PT_progmem_buffer(), '%*s': PT_buffer(),
}
# Lookup the message types for a format string
def lookup_params(msgformat, enumerations={}):
out = []
argparts = [arg.split('=') for arg in msgformat.split()[1:]]
for name, fmt in argparts:
pt = MessageTypes[fmt]
for enum_name, enums in enumerations.items():
if name == enum_name or name.endswith('_' + enum_name):
pt = Enumeration(pt, enum_name, enums)
break
out.append((name, pt))
return out
# Lookup the message types for a debugging "output()" format string
def lookup_output_params(msgformat):
param_types = []
args = msgformat
while 1:
pos = args.find('%')
if pos < 0:
break
if pos+1 >= len(args) or args[pos+1] != '%':
for i in range(4):
t = MessageTypes.get(args[pos:pos+1+i])
if t is not None:
param_types.append(t)
break
else:
raise error("Invalid output format for '%s'" % (msgformat,))
args = args[pos+1:]
return param_types
# Update the message format to be compatible with python's % operator
def convert_msg_format(msgformat):
for c in ['%u', '%i', '%hu', '%hi', '%c', '%.*s', '%*s']:
msgformat = msgformat.replace(c, '%s')
return msgformat
class MessageFormat:
def __init__(self, msgid, msgformat, enumerations={}):
self.msgid = msgid
self.msgformat = msgformat
self.debugformat = convert_msg_format(msgformat)
self.name = msgformat.split()[0]
self.param_names = lookup_params(msgformat, enumerations)
self.param_types = [t for name, t in self.param_names]
self.name_to_type = dict(self.param_names)
def encode(self, params):
out = []
out.append(self.msgid)
for i, t in enumerate(self.param_types):
t.encode(out, params[i])
return out
def encode_by_name(self, **params):
out = []
out.append(self.msgid)
for name, t in self.param_names:
t.encode(out, params[name])
return out
def parse(self, s, pos):
pos += 1
out = {}
for name, t in self.param_names:
v, pos = t.parse(s, pos)
out[name] = v
return out, pos
def format_params(self, params):
out = []
for name, t in self.param_names:
v = params[name]
if t.is_dynamic_string:
v = repr(v)
out.append(v)
return self.debugformat % tuple(out)
class OutputFormat:
name = '#output'
def __init__(self, msgid, msgformat):
self.msgid = msgid
self.msgformat = msgformat
self.debugformat = convert_msg_format(msgformat)
self.param_types = lookup_output_params(msgformat)
def parse(self, s, pos):
pos += 1
out = []
for t in self.param_types:
v, pos = t.parse(s, pos)
if t.is_dynamic_string:
v = repr(v)
out.append(v)
outmsg = self.debugformat % tuple(out)
return {'#msg': outmsg}, pos
def format_params(self, params):
return "#output %s" % (params['#msg'],)
class UnknownFormat:
name = '#unknown'
def parse(self, s, pos):
msgid = s[pos]
msg = bytes(bytearray(s))
return {'#msgid': msgid, '#msg': msg}, len(s)-MESSAGE_TRAILER_SIZE
def format_params(self, params):
return "#unknown %s" % (repr(params['#msg']),)
class MessageParser:
error = error
def __init__(self, warn_prefix=""):
self.warn_prefix = warn_prefix
self.unknown = UnknownFormat()
self.enumerations = {}
self.messages = []
self.messages_by_id = {}
self.messages_by_name = {}
self.config = {}
self.version = self.build_versions = ""
self.raw_identify_data = ""
self._init_messages(DefaultMessages)
def _error(self, msg, *params):
raise error(self.warn_prefix + (msg % params))
def check_packet(self, s):
if len(s) < MESSAGE_MIN:
return 0
msglen = ord(s[MESSAGE_POS_LEN])
if msglen < MESSAGE_MIN or msglen > MESSAGE_MAX:
return -1
msgseq = ord(s[MESSAGE_POS_SEQ])
if (msgseq & ~MESSAGE_SEQ_MASK) != MESSAGE_DEST:
return -1
if len(s) < msglen:
# Need more data
return 0
if s[msglen-MESSAGE_TRAILER_SYNC] != MESSAGE_SYNC:
return -1
msgcrc = s[msglen-MESSAGE_TRAILER_CRC:msglen-MESSAGE_TRAILER_CRC+2]
crc = crc16_ccitt(s[:msglen-MESSAGE_TRAILER_SIZE])
if crc != msgcrc:
#logging.debug("got crc %s vs %s", repr(crc), repr(msgcrc))
return -1
return msglen
def dump(self, s):
msgseq = s[MESSAGE_POS_SEQ]
out = ["seq: %02x" % (msgseq,)]
pos = MESSAGE_HEADER_SIZE
while 1:
msgid = s[pos]
mid = self.messages_by_id.get(msgid, self.unknown)
params, pos = mid.parse(s, pos)
out.append(mid.format_params(params))
if pos >= len(s)-MESSAGE_TRAILER_SIZE:
break
return out
def format_params(self, params):
name = params.get('#name')
mid = self.messages_by_name.get(name)
if mid is not None:
return mid.format_params(params)
msg = params.get('#msg')
if msg is not None:
return "%s %s" % (name, msg)
return str(params)
def parse(self, s):
msgid = s[MESSAGE_HEADER_SIZE]
mid = self.messages_by_id.get(msgid, self.unknown)
params, pos = mid.parse(s, MESSAGE_HEADER_SIZE)
if pos != len(s)-MESSAGE_TRAILER_SIZE:
self._error("Extra data at end of message")
params['#name'] = mid.name
return params
def encode(self, seq, cmd):
msglen = MESSAGE_MIN + len(cmd)
seq = (seq & MESSAGE_SEQ_MASK) | MESSAGE_DEST
out = [chr(msglen), chr(seq), cmd]
out.append(crc16_ccitt(''.join(out)))
out.append(MESSAGE_SYNC)
return ''.join(out)
def _parse_buffer(self, value):
if not value:
return []
tval = int(value, 16)
out = []
for i in range(len(value) // 2):
out.append(tval & 0xff)
tval >>= 8
out.reverse()
return out
def lookup_command(self, msgformat):
parts = msgformat.strip().split()
msgname = parts[0]
mp = self.messages_by_name.get(msgname)
if mp is None:
self._error("Unknown command: %s", msgname)
if msgformat != mp.msgformat:
self._error("Command format mismatch: %s vs %s",
msgformat, mp.msgformat)
return mp
def create_command(self, msg):
parts = msg.strip().split()
if not parts:
return ""
msgname = parts[0]
mp = self.messages_by_name.get(msgname)
if mp is None:
self._error("Unknown command: %s", msgname)
try:
argparts = dict(arg.split('=', 1) for arg in parts[1:])
for name, value in argparts.items():
t = mp.name_to_type[name]
if t.is_dynamic_string:
tval = self._parse_buffer(value)
elif t.is_int:
tval = int(value, 0)
else:
tval = value
argparts[name] = tval
except error as e:
raise
except:
#logging.exception("Unable to extract params")
self._error("Unable to extract params from: %s", msgname)
try:
cmd = mp.encode_by_name(**argparts)
except error as e:
raise
except:
#logging.exception("Unable to encode")
self._error("Unable to encode: %s", msgname)
return cmd
def fill_enumerations(self, enumerations):
for add_name, add_enums in enumerations.items():
enums = self.enumerations.setdefault(add_name, {})
for enum, value in add_enums.items():
if type(value) == type(0):
# Simple enumeration
enums[str(enum)] = value
continue
# Enumeration range
enum = enum_root = str(enum)
while enum_root and enum_root[-1].isdigit():
enum_root = enum_root[:-1]
start_enum = 0
if len(enum_root) != len(enum):
start_enum = int(enum[len(enum_root):])
start_value, count = value
for i in range(count):
enums[enum_root + str(start_enum + i)] = start_value + i
def _init_messages(self, messages, command_tags=[], output_tags=[]):
for msgformat, msgtag in messages.items():
msgtype = 'response'
if msgtag in command_tags:
msgtype = 'command'
elif msgtag in output_tags:
msgtype = 'output'
self.messages.append((msgtag, msgtype, msgformat))
if msgtag < -32 or msgtag > 95:
self._error("Multi-byte msgtag not supported")
msgid = msgtag & 0x7f
if msgtype == 'output':
self.messages_by_id[msgid] = OutputFormat(msgid, msgformat)
else:
msg = MessageFormat(msgid, msgformat, self.enumerations)
self.messages_by_id[msgid] = msg
self.messages_by_name[msg.name] = msg
def process_identify(self, data, decompress=True):
try:
if decompress:
data = zlib.decompress(data)
self.raw_identify_data = data
data = json.loads(data)
self.fill_enumerations(data.get('enumerations', {}))
commands = data.get('commands')
responses = data.get('responses')
output = data.get('output', {})
all_messages = dict(commands)
all_messages.update(responses)
all_messages.update(output)
self._init_messages(all_messages, commands.values(),
output.values())
self.config.update(data.get('config', {}))
self.version = data.get('version', '')
self.build_versions = data.get('build_versions', '')
except error as e:
raise
except Exception as e:
logging.exception("process_identify error")
self._error("Error during identify: %s", str(e))
def get_raw_data_dictionary(self):
return self.raw_identify_data
def get_version_info(self):
return self.version, self.build_versions
def get_messages(self):
return list(self.messages)
def get_enumerations(self):
return dict(self.enumerations)
def get_constants(self):
return dict(self.config)
class sentinel: pass
def get_constant(self, name, default=sentinel, parser=str):
if name not in self.config:
if default is not self.sentinel:
return default
self._error("Firmware constant '%s' not found", name)
try:
value = parser(self.config[name])
except:
self._error("Unable to parse firmware constant %s: %s",
name, self.config[name])
return value
def get_constant_float(self, name, default=sentinel):
return self.get_constant(name, default, parser=float)
def get_constant_int(self, name, default=sentinel):
return self.get_constant(name, default, parser=int)