.. contents ::
+Nanopb-0.3.2 (2015-01-xx)
+=========================
+
+Add support for OneOfs
+----------------------
+**Rationale:** Previously nanopb did not support the *oneof* construct in
+*.proto* files. Those fields were generated as regular *optional* fields.
+
+**Changes:** OneOfs are now generated as C unions. Callback fields are not
+supported inside oneof and generator gives an error.
+
+**Required actions:** The generator option *no_unions* can be used to restore old
+behaviour and to allow callbacks to be used. To use unions, one change is
+needed: use *which_xxxx* field to detect which field is present, instead
+of *has_xxxx*. Compare the value against *MyStruct_myfield_tag*.
+
+**Error indications:** Generator error: "Callback fields inside of oneof are
+not supported". Compiler error: "Message" has no member named "has_xxxx".
+
Nanopb-0.3.0 (2014-08-26)
=========================
def add_field(self, field):
if field.allocation == 'CALLBACK':
raise Exception("Callback fields inside of oneof are not supported"
- + " (field %s)" % field.fullname)
+ + " (field %s)" % field.name)
field.union_name = self.name
field.rules = 'ONEOF'
def __init__(self, names, desc, message_options):
self.name = names
self.fields = []
- self.oneofs = []
+ self.oneofs = {}
+ no_unions = []
if hasattr(desc, 'oneof_decl'):
- for f in desc.oneof_decl:
- oneof = OneOf(self.name, f)
- self.oneofs.append(oneof)
- self.fields.append(oneof)
+ for i, f in enumerate(desc.oneof_decl):
+ oneof_options = get_nanopb_suboptions(desc, message_options, self.name + f.name)
+ if oneof_options.no_unions:
+ no_unions.append(i) # No union, but add fields normally
+ elif oneof_options.type == nanopb_pb2.FT_IGNORE:
+ pass # No union and skip fields also
+ else:
+ oneof = OneOf(self.name, f)
+ self.oneofs[i] = oneof
+ self.fields.append(oneof)
for f in desc.field:
field_options = get_nanopb_suboptions(f, message_options, self.name + f.name)
continue
field = Field(self.name, f, field_options)
- if hasattr(f, 'oneof_index') and f.HasField('oneof_index'):
- self.oneofs[f.oneof_index].add_field(field)
+ if (hasattr(f, 'oneof_index') and
+ f.HasField('oneof_index') and
+ f.oneof_index not in no_unions):
+ if f.oneof_index in self.oneofs:
+ self.oneofs[f.oneof_index].add_field(field)
else:
self.fields.append(field)
'''Returns number of required fields inside this message'''
count = 0
for f in self.fields:
- if f not in self.oneofs:
+ if not isinstance(f, OneOf):
if f.rules == 'REQUIRED':
count += 1
return count
def count_all_fields(self):
count = 0
for f in self.fields:
- if f in self.oneofs:
+ if isinstance(f, OneOf):
count += len(f.fields)
else:
count += 1