def from_declaration(cls, code):
name = code.target.id
pos = 0
# Determine the arguments, expects something of the form def foo(arg1: num, arg2: num ...
args = []
indexed_list = []
topics_count = 1
if code.annotation.args:
keys = code.annotation.args[0].keys
values = code.annotation.args[0].values
for i in range(len(keys)):
typ = values[i]
arg = keys[i].id
is_indexed = False
# Check to see if argument is a topic
if isinstance(typ, ast.Call) and typ.func.id == 'indexed':
typ = values[i].args[0]
indexed_list.append(True)
topics_count += 1
is_indexed = True
else:
indexed_list.append(False)
if hasattr(
typ,
'left') and typ.left.id == 'bytes' and typ.comparators[
0].n > 32 and is_indexed:
raise VariableDeclarationException(
"Indexed arguments are limited to 32 bytes")
if topics_count > 4:
raise VariableDeclarationException(
"Maximum of 3 topics {} given".format(topics_count -
1), arg)
if not isinstance(arg, str):
raise VariableDeclarationException("Argument name invalid",
arg)
if not typ:
raise InvalidTypeException("Argument must have type", arg)
if not is_varname_valid(arg):
raise VariableDeclarationException(
"Argument name invalid or reserved: " + arg, arg)
if arg in (x.name for x in args):
raise VariableDeclarationException(
"Duplicate function argument name: " + arg, arg)
parsed_type = parse_type(typ, None)
args.append(VariableRecord(arg, pos, parsed_type, False))
if isinstance(parsed_type, ByteArrayType):
pos += ceil32(typ.comparators[0].n)
else:
pos += get_size_of_type(parsed_type) * 32
sig = name + '(' + ','.join([
canonicalize_type(arg.typ, indexed_list[pos])
for pos, arg in enumerate(args)
]) + ')'
event_id = bytes_to_int(sha3(bytes(sig, 'utf-8')))
return cls(name, args, indexed_list, event_id, sig)
def pack_arguments(signature, args, context):
placeholder_typ = ByteArrayType(
maxlen=sum([get_size_of_type(arg.typ)
for arg in signature.args]) * 32 + 32)
placeholder = context.new_placeholder(placeholder_typ)
setters = [['mstore', placeholder, signature.method_id]]
needpos = False
expected_arg_count = len(signature.args)
actual_arg_count = len(args)
if actual_arg_count != expected_arg_count:
raise StructureException(
"Wrong number of args for: %s (%s args, expected %s)" %
(signature.name, actual_arg_count, expected_arg_count))
for i, (arg,
typ) in enumerate(zip(args, [arg.typ for arg in signature.args])):
if isinstance(typ, BaseType):
setters.append(
make_setter(
LLLnode.from_list(placeholder + 32 + i * 32, typ=typ), arg,
'memory'))
elif isinstance(typ, ByteArrayType):
setters.append(['mstore', placeholder + 32 + i * 32, '_poz'])
arg_copy = LLLnode.from_list('_s',
typ=arg.typ,
location=arg.location)
target = LLLnode.from_list(['add', placeholder + 32, '_poz'],
typ=typ,
location='memory')
setters.append([
'with', '_s', arg,
[
'seq',
make_byte_array_copier(target, arg_copy),
[
'set', '_poz',
['add', 32, ['add', '_poz',
get_length(arg_copy)]]
]
]
])
needpos = True
else:
raise TypeMismatchException("Cannot pack argument of type %r" %
typ)
if needpos:
return LLLnode.from_list(['with', '_poz', len(args) * 32, ['seq'] + setters + [placeholder + 28]],
typ=placeholder_typ, location='memory'), \
placeholder_typ.maxlen - 28
else:
return LLLnode.from_list(['seq'] + setters + [placeholder + 28], typ=placeholder_typ, location='memory'), \
placeholder_typ.maxlen - 28
def parse_return(self):
from .parser import (parse_expr, make_setter)
if self.context.return_type is None:
if self.stmt.value:
raise TypeMismatchException("Not expecting to return a value",
self.stmt)
return LLLnode.from_list(['return', 0, 0],
typ=None,
pos=getpos(self.stmt))
if not self.stmt.value:
raise TypeMismatchException("Expecting to return a value",
self.stmt)
sub = parse_expr(self.stmt.value, self.context)
# Returning a value (most common case)
if isinstance(sub.typ, BaseType):
if not isinstance(self.context.return_type, BaseType):
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
sub = unwrap_location(sub)
if not are_units_compatible(sub.typ, self.context.return_type):
raise TypeMismatchException(
"Return type units mismatch %r %r" %
(sub.typ, self.context.return_type), self.stmt.value)
elif is_base_type(sub.typ, self.context.return_type.typ) or \
(is_base_type(sub.typ, 'num') and is_base_type(self.context.return_type, 'signed256')):
return LLLnode.from_list(
['seq', ['mstore', 0, sub], ['return', 0, 32]],
typ=None,
pos=getpos(self.stmt))
else:
raise TypeMismatchException(
"Unsupported type conversion: %r to %r" %
(sub.typ, self.context.return_type), self.stmt.value)
# Returning a byte array
elif isinstance(sub.typ, ByteArrayType):
if not isinstance(self.context.return_type, ByteArrayType):
raise TypeMismatchException(
"Trying to return base type %r, output expecting %r" %
(sub.typ, self.context.return_type), self.stmt.value)
if sub.typ.maxlen > self.context.return_type.maxlen:
raise TypeMismatchException(
"Cannot cast from greater max-length %d to shorter max-length %d"
% (sub.typ.maxlen, self.context.return_type.maxlen),
self.stmt.value)
# Returning something already in memory
if sub.location == 'memory':
return LLLnode.from_list([
'with', '_loc', sub,
[
'seq', ['mstore', ['sub', '_loc', 32], 32],
[
'return', ['sub', '_loc', 32],
['ceil32', ['add', ['mload', '_loc'], 64]]
]
]
],
typ=None,
pos=getpos(self.stmt))
# Copying from storage
elif sub.location == 'storage':
# Instantiate a byte array at some index
fake_byte_array = LLLnode(self.context.get_next_mem() + 32,
typ=sub.typ,
location='memory',
pos=getpos(self.stmt))
o = [
'seq',
# Copy the data to this byte array
make_byte_array_copier(fake_byte_array, sub),
# Store the number 32 before it for ABI formatting purposes
['mstore', self.context.get_next_mem(), 32],
# Return it
[
'return',
self.context.get_next_mem(),
[
'add',
[
'ceil32',
['mload',
self.context.get_next_mem() + 32]
], 64
]
]
]
return LLLnode.from_list(o, typ=None, pos=getpos(self.stmt))
else:
raise Exception("Invalid location: %s" % sub.location)
# Returning a list
elif isinstance(sub.typ, ListType):
if sub.location == "memory" and sub.value != "multi":
return LLLnode.from_list([
'return', sub,
get_size_of_type(self.context.return_type) * 32
],
typ=None,
pos=getpos(self.stmt))
else:
new_sub = LLLnode.from_list(self.context.new_placeholder(
self.context.return_type),
typ=self.context.return_type,
location='memory')
setter = make_setter(new_sub, sub, 'memory')
return LLLnode.from_list([
'seq', setter,
[
'return', new_sub,
get_size_of_type(self.context.return_type) * 32
]
],
typ=None,
pos=getpos(self.stmt))
else:
raise TypeMismatchException("Can only return base type!",
self.stmt)
