blob: d2d7db0b6ba050479db59c1a6bf9b71cb5b57ddb [file] [log] [blame]
'''Generate header file for nanopb from a ProtoBuf FileDescriptorSet.'''
nanopb_version = "nanopb-"
import sys
# Add some dummy imports to keep packaging tools happy.
import google, distutils.util # bbfreeze seems to need these
import pkg_resources # pyinstaller / protobuf 2.5 seem to need these
# Don't care, we will error out later if it is actually important.
import google.protobuf.text_format as text_format
import google.protobuf.descriptor_pb2 as descriptor
*** Could not import the Google protobuf Python libraries ***
*** Try installing package 'python-protobuf' or similar. ***
''' + '\n')
import proto.nanopb_pb2 as nanopb_pb2
import proto.plugin_pb2 as plugin_pb2
*** Failed to import the protocol definitions for generator. ***
*** You have to run 'make' in the nanopb/generator/proto folder. ***
''' + '\n')
# ---------------------------------------------------------------------------
# Generation of single fields
# ---------------------------------------------------------------------------
import time
import os.path
# Values are tuple (c type, pb type, encoded size)
FieldD = descriptor.FieldDescriptorProto
datatypes = {
FieldD.TYPE_BOOL: ('bool', 'BOOL', 1),
FieldD.TYPE_DOUBLE: ('double', 'DOUBLE', 8),
FieldD.TYPE_FIXED32: ('uint32_t', 'FIXED32', 4),
FieldD.TYPE_FIXED64: ('uint64_t', 'FIXED64', 8),
FieldD.TYPE_FLOAT: ('float', 'FLOAT', 4),
FieldD.TYPE_INT32: ('int32_t', 'INT32', 10),
FieldD.TYPE_INT64: ('int64_t', 'INT64', 10),
FieldD.TYPE_SFIXED32: ('int32_t', 'SFIXED32', 4),
FieldD.TYPE_SFIXED64: ('int64_t', 'SFIXED64', 8),
FieldD.TYPE_SINT32: ('int32_t', 'SINT32', 5),
FieldD.TYPE_SINT64: ('int64_t', 'SINT64', 10),
FieldD.TYPE_UINT32: ('uint32_t', 'UINT32', 5),
FieldD.TYPE_UINT64: ('uint64_t', 'UINT64', 10)
class Names:
'''Keeps a set of nested names and formats them to C identifier.'''
def __init__(self, parts = ()):
if isinstance(parts, Names):
parts = = tuple(parts)
def __str__(self):
return '_'.join(
def __add__(self, other):
if isinstance(other, (str, unicode)):
return Names( + (other,))
elif isinstance(other, tuple):
return Names( + other)
raise ValueError("Name parts should be of type str")
def __eq__(self, other):
return isinstance(other, Names) and ==
def names_from_type_name(type_name):
'''Parse Names() from FieldDescriptorProto type_name'''
if type_name[0] != '.':
raise NotImplementedError("Lookup of non-absolute type names is not supported")
return Names(type_name[1:].split('.'))
def varint_max_size(max_value):
'''Returns the maximum number of bytes a varint can take when encoded.'''
for i in range(1, 11):
if (max_value >> (i * 7)) == 0:
return i
raise ValueError("Value too large for varint: " + str(max_value))
assert varint_max_size(0) == 1
assert varint_max_size(127) == 1
assert varint_max_size(128) == 2
class EncodedSize:
'''Class used to represent the encoded size of a field or a message.
Consists of a combination of symbolic sizes and integer sizes.'''
def __init__(self, value = 0, symbols = []):
if isinstance(value, (str, Names)):
symbols = [str(value)]
value = 0
self.value = value
self.symbols = symbols
def __add__(self, other):
if isinstance(other, (int, long)):
return EncodedSize(self.value + other, self.symbols)
elif isinstance(other, (str, Names)):
return EncodedSize(self.value, self.symbols + [str(other)])
elif isinstance(other, EncodedSize):
return EncodedSize(self.value + other.value, self.symbols + other.symbols)
raise ValueError("Cannot add size: " + repr(other))
def __mul__(self, other):
if isinstance(other, (int, long)):
return EncodedSize(self.value * other, [str(other) + '*' + s for s in self.symbols])
raise ValueError("Cannot multiply size: " + repr(other))
def __str__(self):
if not self.symbols:
return str(self.value)
return '(' + str(self.value) + ' + ' + ' + '.join(self.symbols) + ')'
def upperlimit(self):
if not self.symbols:
return self.value
return 2**32 - 1
class Enum:
def __init__(self, names, desc, enum_options):
'''desc is EnumDescriptorProto'''
self.options = enum_options
self.names = names +
if enum_options.long_names:
self.values = [(self.names +, x.number) for x in desc.value]
self.values = [(names +, x.number) for x in desc.value]
self.value_longnames = [self.names + for x in desc.value]
def __str__(self):
result = 'typedef enum _%s {\n' % self.names
result += ',\n'.join([" %s = %d" % x for x in self.values])
result += '\n} %s;' % self.names
return result
class Field:
def __init__(self, struct_name, desc, field_options):
'''desc is FieldDescriptorProto'''
self.tag = desc.number
self.struct_name = struct_name =
self.default = None
self.max_size = None
self.max_count = None
self.array_decl = ""
self.enc_size = None
self.ctype = None
# Parse field options
if field_options.HasField("max_size"):
self.max_size = field_options.max_size
if field_options.HasField("max_count"):
self.max_count = field_options.max_count
if desc.HasField('default_value'):
self.default = desc.default_value
# Check field rules, i.e. required/optional/repeated.
can_be_static = True
if desc.label == FieldD.LABEL_REQUIRED:
self.rules = 'REQUIRED'
elif desc.label == FieldD.LABEL_OPTIONAL:
self.rules = 'OPTIONAL'
elif desc.label == FieldD.LABEL_REPEATED:
self.rules = 'REPEATED'
if self.max_count is None:
can_be_static = False
self.array_decl = '[%d]' % self.max_count
raise NotImplementedError(desc.label)
# Check if the field can be implemented with static allocation
# i.e. whether the data size is known.
if desc.type == FieldD.TYPE_STRING and self.max_size is None:
can_be_static = False
if desc.type == FieldD.TYPE_BYTES and self.max_size is None:
can_be_static = False
# Decide how the field data will be allocated
if field_options.type == nanopb_pb2.FT_DEFAULT:
if can_be_static:
field_options.type = nanopb_pb2.FT_STATIC
field_options.type = nanopb_pb2.FT_CALLBACK
if field_options.type == nanopb_pb2.FT_STATIC and not can_be_static:
raise Exception("Field %s is defined as static, but max_size or "
"max_count is not given." %
if field_options.type == nanopb_pb2.FT_STATIC:
self.allocation = 'STATIC'
elif field_options.type == nanopb_pb2.FT_POINTER:
self.allocation = 'POINTER'
elif field_options.type == nanopb_pb2.FT_CALLBACK:
self.allocation = 'CALLBACK'
raise NotImplementedError(field_options.type)
# Decide the C data type to use in the struct.
if datatypes.has_key(desc.type):
self.ctype, self.pbtype, self.enc_size = datatypes[desc.type]
elif desc.type == FieldD.TYPE_ENUM:
self.pbtype = 'ENUM'
self.ctype = names_from_type_name(desc.type_name)
if self.default is not None:
self.default = self.ctype + self.default
self.enc_size = 5 # protoc rejects enum values > 32 bits
elif desc.type == FieldD.TYPE_STRING:
self.pbtype = 'STRING'
self.ctype = 'char'
if self.allocation == 'STATIC':
self.ctype = 'char'
self.array_decl += '[%d]' % self.max_size
self.enc_size = varint_max_size(self.max_size) + self.max_size
elif desc.type == FieldD.TYPE_BYTES:
self.pbtype = 'BYTES'
if self.allocation == 'STATIC':
self.ctype = self.struct_name + + 't'
self.enc_size = varint_max_size(self.max_size) + self.max_size
elif self.allocation == 'POINTER':
self.ctype = 'pb_bytes_array_t'
elif desc.type == FieldD.TYPE_MESSAGE:
self.pbtype = 'MESSAGE'
self.ctype = self.submsgname = names_from_type_name(desc.type_name)
self.enc_size = None # Needs to be filled in after the message type is available
raise NotImplementedError(desc.type)
def __cmp__(self, other):
return cmp(self.tag, other.tag)
def __str__(self):
result = ''
if self.allocation == 'POINTER':
if self.rules == 'REPEATED':
result += ' size_t ' + + '_count;\n'
if self.pbtype == 'MESSAGE':
# Use struct definition, so recursive submessages are possible
result += ' struct _%s *%s;' % (self.ctype,
elif self.rules == 'REPEATED' and self.pbtype in ['STRING', 'BYTES']:
# String/bytes arrays need to be defined as pointers to pointers
result += ' %s **%s;' % (self.ctype,
result += ' %s *%s;' % (self.ctype,
elif self.allocation == 'CALLBACK':
result += ' pb_callback_t %s;' %
if self.rules == 'OPTIONAL' and self.allocation == 'STATIC':
result += ' bool has_' + + ';\n'
elif self.rules == 'REPEATED' and self.allocation == 'STATIC':
result += ' size_t ' + + '_count;\n'
result += ' %s %s%s;' % (self.ctype,, self.array_decl)
return result
def types(self):
'''Return definitions for any special types this field might need.'''
if self.pbtype == 'BYTES' and self.allocation == 'STATIC':
result = 'typedef struct {\n'
result += ' size_t size;\n'
result += ' uint8_t bytes[%d];\n' % self.max_size
result += '} %s;\n' % self.ctype
result = None
return result
def get_initializer(self, null_init):
'''Return literal expression for this field's default value.'''
if self.pbtype == 'MESSAGE':
if null_init:
return '%s_init_zero' % self.ctype
return '%s_init_default' % self.ctype
if self.default is None or null_init:
if self.pbtype == 'STRING':
return '""'
elif self.pbtype == 'BYTES':
return '{0, {0}}'
elif self.pbtype == 'ENUM':
return '(%s)0' % self.ctype
return '0'
default = str(self.default)
if self.pbtype == 'STRING':
default = default.encode('utf-8').encode('string_escape')
default = default.replace('"', '\\"')
default = '"' + default + '"'
elif self.pbtype == 'BYTES':
data = default.decode('string_escape')
data = ['0x%02x' % ord(c) for c in data]
if len(data) == 0:
default = '{0, {0}}'
default = '{%d, {%s}}' % (len(data), ','.join(data))
elif self.pbtype in ['FIXED32', 'UINT32']:
default += 'u'
elif self.pbtype in ['FIXED64', 'UINT64']:
default += 'ull'
elif self.pbtype in ['SFIXED64', 'INT64']:
default += 'll'
return default
def default_decl(self, declaration_only = False):
'''Return definition for this field's default value.'''
if self.default is None:
return None
ctype = self.ctype
default = self.get_initializer(False)
array_decl = ''
if self.pbtype == 'STRING':
if self.allocation != 'STATIC':
return None # Not implemented
array_decl = '[%d]' % self.max_size
elif self.pbtype == 'BYTES':
if self.allocation != 'STATIC':
return None # Not implemented
if declaration_only:
return 'extern const %s %s_default%s;' % (ctype, self.struct_name +, array_decl)
return 'const %s %s_default%s = %s;' % (ctype, self.struct_name +, array_decl, default)
def tags(self):
'''Return the #define for the tag number of this field.'''
identifier = '%s_%s_tag' % (self.struct_name,
return '#define %-40s %d\n' % (identifier, self.tag)
def pb_field_t(self, prev_field_name):
'''Return the pb_field_t initializer to use in the constant array.
prev_field_name is the name of the previous field or None.
result = ' PB_FIELD2(%3d, ' % self.tag
result += '%-8s, ' % self.pbtype
result += '%s, ' % self.rules
result += '%-8s, ' % self.allocation
result += '%s, ' % ("FIRST" if not prev_field_name else "OTHER")
result += '%s, ' % self.struct_name
result += '%s, ' %
result += '%s, ' % (prev_field_name or
if self.pbtype == 'MESSAGE':
result += '&%s_fields)' % self.submsgname
elif self.default is None:
result += '0)'
elif self.pbtype in ['BYTES', 'STRING'] and self.allocation != 'STATIC':
result += '0)' # Arbitrary size default values not implemented
elif self.rules == 'OPTEXT':
result += '0)' # Default value for extensions is not implemented
result += '&%s_default)' % (self.struct_name +
return result
def largest_field_value(self):
'''Determine if this field needs 16bit or 32bit pb_field_t structure to compile properly.
Returns numeric value or a C-expression for assert.'''
if self.pbtype == 'MESSAGE':
if self.rules == 'REPEATED' and self.allocation == 'STATIC':
return 'pb_membersize(%s, %s[0])' % (self.struct_name,
return 'pb_membersize(%s, %s)' % (self.struct_name,
return max(self.tag, self.max_size, self.max_count)
def encoded_size(self, allmsgs):
'''Return the maximum size that this field can take when encoded,
including the field tag. If the size cannot be determined, returns
if self.allocation != 'STATIC':
return None
if self.pbtype == 'MESSAGE':
for msg in allmsgs:
if == self.submsgname:
encsize = msg.encoded_size(allmsgs)
if encsize is None:
return None # Submessage size is indeterminate
# Include submessage length prefix
encsize += varint_max_size(encsize.upperlimit())
# Submessage cannot be found, this currently occurs when
# the submessage type is defined in a different file.
# Instead of direct numeric value, reference the size that
# has been #defined in the other file.
encsize = EncodedSize(self.submsgname + 'size')
# We will have to make a conservative assumption on the length
# prefix size, though.
encsize += 5
elif self.enc_size is None:
raise RuntimeError("Could not determine encoded size for %s.%s"
% (self.struct_name,
encsize = EncodedSize(self.enc_size)
encsize += varint_max_size(self.tag << 3) # Tag + wire type
if self.rules == 'REPEATED':
# Decoders must be always able to handle unpacked arrays.
# Therefore we have to reserve space for it, even though
# we emit packed arrays ourselves.
encsize *= self.max_count
return encsize
class ExtensionRange(Field):
def __init__(self, struct_name, range_start, field_options):
'''Implements a special pb_extension_t* field in an extensible message
structure. The range_start signifies the index at which the extensions
start. Not necessarily all tags above this are extensions, it is merely
a speed optimization.
self.tag = range_start
self.struct_name = struct_name = 'extensions'
self.pbtype = 'EXTENSION'
self.rules = 'OPTIONAL'
self.allocation = 'CALLBACK'
self.ctype = 'pb_extension_t'
self.array_decl = ''
self.default = None
self.max_size = 0
self.max_count = 0
def __str__(self):
return ' pb_extension_t *extensions;'
def types(self):
return None
def tags(self):
return ''
def encoded_size(self, allmsgs):
# We exclude extensions from the count, because they cannot be known
# until runtime. Other option would be to return None here, but this
# way the value remains useful if extensions are not used.
return EncodedSize(0)
class ExtensionField(Field):
def __init__(self, struct_name, desc, field_options):
self.fullname = struct_name +
self.extendee_name = names_from_type_name(desc.extendee)
Field.__init__(self, self.fullname + 'struct', desc, field_options)
if self.rules != 'OPTIONAL':
self.skip = True
self.skip = False
self.rules = 'OPTEXT'
def tags(self):
'''Return the #define for the tag number of this field.'''
identifier = '%s_tag' % self.fullname
return '#define %-40s %d\n' % (identifier, self.tag)
def extension_decl(self):
'''Declaration of the extension type in the .pb.h file'''
if self.skip:
msg = '/* Extension field %s was skipped because only "optional"\n' % self.fullname
msg +=' type of extension fields is currently supported. */\n'
return msg
return 'extern const pb_extension_type_t %s;\n' % self.fullname
def extension_def(self):
'''Definition of the extension type in the .pb.c file'''
if self.skip:
return ''
result = 'typedef struct {\n'
result += str(self)
result += '\n} %s;\n\n' % self.struct_name
result += ('static const pb_field_t %s_field = \n %s;\n\n' %
(self.fullname, self.pb_field_t(None)))
result += 'const pb_extension_type_t %s = {\n' % self.fullname
result += ' NULL,\n'
result += ' NULL,\n'
result += ' &%s_field\n' % self.fullname
result += '};\n'
return result
# ---------------------------------------------------------------------------
# Generation of messages (structures)
# ---------------------------------------------------------------------------
class Message:
def __init__(self, names, desc, message_options): = names
self.fields = []
for f in desc.field:
field_options = get_nanopb_suboptions(f, message_options, +
if field_options.type != nanopb_pb2.FT_IGNORE:
self.fields.append(Field(, f, field_options))
if len(desc.extension_range) > 0:
field_options = get_nanopb_suboptions(desc, message_options, + 'extensions')
range_start = min([r.start for r in desc.extension_range])
if field_options.type != nanopb_pb2.FT_IGNORE:
self.fields.append(ExtensionRange(, range_start, field_options))
self.packed = message_options.packed_struct
self.ordered_fields = self.fields[:]
def get_dependencies(self):
'''Get list of type names that this structure refers to.'''
return [str(field.ctype) for field in self.fields]
def __str__(self):
result = 'typedef struct _%s {\n' %
if not self.ordered_fields:
# Empty structs are not allowed in C standard.
# Therefore add a dummy field if an empty message occurs.
result += ' uint8_t dummy_field;'
result += '\n'.join([str(f) for f in self.ordered_fields])
result += '\n}'
if self.packed:
result += ' pb_packed'
result += ' %s;' %
if self.packed:
result = 'PB_PACKED_STRUCT_START\n' + result
result += '\nPB_PACKED_STRUCT_END'
return result
def types(self):
result = ""
for field in self.fields:
types = field.types()
if types is not None:
result += types + '\n'
return result
def get_initializer(self, null_init):
if not self.ordered_fields:
return '{0}'
parts = []
for field in self.ordered_fields:
if field.allocation == 'STATIC':
if field.rules == 'REPEATED':
+ ', '.join([field.get_initializer(null_init)] * field.max_count)
+ '}')
elif field.rules == 'OPTIONAL':
elif field.allocation == 'POINTER':
if field.rules == 'REPEATED':
elif field.allocation == 'CALLBACK':
if field.pbtype == 'EXTENSION':
parts.append('{{NULL}, NULL}')
return '{' + ', '.join(parts) + '}'
def default_decl(self, declaration_only = False):
result = ""
for field in self.fields:
default = field.default_decl(declaration_only)
if default is not None:
result += default + '\n'
return result
def fields_declaration(self):
result = 'extern const pb_field_t %s_fields[%d];' % (, len(self.fields) + 1)
return result
def fields_definition(self):
result = 'const pb_field_t %s_fields[%d] = {\n' % (, len(self.fields) + 1)
prev = None
for field in self.ordered_fields:
result += field.pb_field_t(prev)
result += ',\n'
prev =
result += ' PB_LAST_FIELD\n};'
return result
def encoded_size(self, allmsgs):
'''Return the maximum size that this message can take when encoded.
If the size cannot be determined, returns None.
size = EncodedSize(0)
for field in self.fields:
fsize = field.encoded_size(allmsgs)
if fsize is None:
return None
size += fsize
return size
# ---------------------------------------------------------------------------
# Processing of entire .proto files
# ---------------------------------------------------------------------------
def iterate_messages(desc, names = Names()):
'''Recursively find all messages. For each, yield name, DescriptorProto.'''
if hasattr(desc, 'message_type'):
submsgs = desc.message_type
submsgs = desc.nested_type
for submsg in submsgs:
sub_names = names +
yield sub_names, submsg
for x in iterate_messages(submsg, sub_names):
yield x
def iterate_extensions(desc, names = Names()):
'''Recursively find all extensions.
For each, yield name, FieldDescriptorProto.
for extension in desc.extension:
yield names, extension
for subname, subdesc in iterate_messages(desc, names):
for extension in subdesc.extension:
yield subname, extension
def parse_file(fdesc, file_options):
'''Takes a FileDescriptorProto and returns tuple (enums, messages, extensions).'''
enums = []
messages = []
extensions = []
if fdesc.package:
base_name = Names(fdesc.package.split('.'))
base_name = Names()
for enum in fdesc.enum_type:
enum_options = get_nanopb_suboptions(enum, file_options, base_name +
enums.append(Enum(base_name, enum, enum_options))
for names, message in iterate_messages(fdesc, base_name):
message_options = get_nanopb_suboptions(message, file_options, names)
if message_options.skip_message:
messages.append(Message(names, message, message_options))
for enum in message.enum_type:
enum_options = get_nanopb_suboptions(enum, message_options, names +
enums.append(Enum(names, enum, enum_options))
for names, extension in iterate_extensions(fdesc, base_name):
field_options = get_nanopb_suboptions(extension, file_options, names +
if field_options.type != nanopb_pb2.FT_IGNORE:
extensions.append(ExtensionField(names, extension, field_options))
# Fix field default values where enum short names are used.
for enum in enums:
if not enum.options.long_names:
for message in messages:
for field in message.fields:
if field.default in enum.value_longnames:
idx = enum.value_longnames.index(field.default)
field.default = enum.values[idx][0]
return enums, messages, extensions
def toposort2(data):
'''Topological sort.
This function is under the MIT license.
for k, v in data.items():
v.discard(k) # Ignore self dependencies
extra_items_in_deps = reduce(set.union, data.values(), set()) - set(data.keys())
data.update(dict([(item, set()) for item in extra_items_in_deps]))
while True:
ordered = set(item for item,dep in data.items() if not dep)
if not ordered:
for item in sorted(ordered):
yield item
data = dict([(item, (dep - ordered)) for item,dep in data.items()
if item not in ordered])
assert not data, "A cyclic dependency exists amongst %r" % data
def sort_dependencies(messages):
'''Sort a list of Messages based on dependencies.'''
dependencies = {}
message_by_name = {}
for message in messages:
dependencies[str(] = set(message.get_dependencies())
message_by_name[str(] = message
for msgname in toposort2(dependencies):
if msgname in message_by_name:
yield message_by_name[msgname]
def make_identifier(headername):
'''Make #ifndef identifier that contains uppercase A-Z and digits 0-9'''
result = ""
for c in headername.upper():
if c.isalnum():
result += c
result += '_'
return result
def generate_header(dependencies, headername, enums, messages, extensions, options):
'''Generate content for a header file.
Generates strings, which should be concatenated and stored to file.
yield '/* Automatically generated nanopb header */\n'
if options.notimestamp:
yield '/* Generated by %s */\n\n' % (nanopb_version)
yield '/* Generated by %s at %s. */\n\n' % (nanopb_version, time.asctime())
symbol = make_identifier(headername)
yield '#ifndef _PB_%s_\n' % symbol
yield '#define _PB_%s_\n' % symbol
yield options.libformat % ('pb.h')
except TypeError:
# no %s specified - use whatever was passed in as options.libformat
yield options.libformat
yield '\n'
for dependency in dependencies:
noext = os.path.splitext(dependency)[0]
yield options.genformat % (noext + options.extension + '.h')
yield '\n'
yield '#ifdef __cplusplus\n'
yield 'extern "C" {\n'
yield '#endif\n\n'
yield '/* Enum definitions */\n'
for enum in enums:
yield str(enum) + '\n\n'
yield '/* Struct definitions */\n'
for msg in sort_dependencies(messages):
yield msg.types()
yield str(msg) + '\n\n'
if extensions:
yield '/* Extensions */\n'
for extension in extensions:
yield extension.extension_decl()
yield '\n'
yield '/* Default values for struct fields */\n'
for msg in messages:
yield msg.default_decl(True)
yield '\n'
yield '/* Initializer values for message structs */\n'
for msg in messages:
identifier = '%s_init_default' %
yield '#define %-40s %s\n' % (identifier, msg.get_initializer(False))
for msg in messages:
identifier = '%s_init_zero' %
yield '#define %-40s %s\n' % (identifier, msg.get_initializer(True))
yield '\n'
yield '/* Field tags (for use in manual encoding/decoding) */\n'
for msg in sort_dependencies(messages):
for field in msg.fields:
yield field.tags()
for extension in extensions:
yield extension.tags()
yield '\n'
yield '/* Struct field encoding specification for nanopb */\n'
for msg in messages:
yield msg.fields_declaration() + '\n'
yield '\n'
yield '/* Maximum encoded size of messages (where known) */\n'
for msg in messages:
msize = msg.encoded_size(messages)
if msize is not None:
identifier = '%s_size' %
yield '#define %-40s %s\n' % (identifier, msize)
yield '\n'
yield '#ifdef __cplusplus\n'
yield '} /* extern "C" */\n'
yield '#endif\n'
# End of header
yield '\n#endif\n'
def generate_source(headername, enums, messages, extensions, options):
'''Generate content for a source file.'''
yield '/* Automatically generated nanopb constant definitions */\n'
if options.notimestamp:
yield '/* Generated by %s */\n\n' % (nanopb_version)
yield '/* Generated by %s at %s. */\n\n' % (nanopb_version, time.asctime())
yield options.genformat % (headername)
yield '\n'
for msg in messages:
yield msg.default_decl(False)
yield '\n\n'
for msg in messages:
yield msg.fields_definition() + '\n\n'
for ext in extensions:
yield ext.extension_def() + '\n'
# Add checks for numeric limits
if messages:
count_required_fields = lambda m: len([f for f in msg.fields if f.rules == 'REQUIRED'])
largest_msg = max(messages, key = count_required_fields)
largest_count = count_required_fields(largest_msg)
if largest_count > 64:
yield '\n/* Check that missing required fields will be properly detected */\n'
yield '#if PB_MAX_REQUIRED_FIELDS < %d\n' % largest_count
yield '#error Properly detecting missing required fields in %s requires \\\n' %
yield ' setting PB_MAX_REQUIRED_FIELDS to %d or more.\n' % largest_count
yield '#endif\n'
worst = 0
worst_field = ''
checks = []
checks_msgnames = []
for msg in messages:
for field in msg.fields:
status = field.largest_field_value()
if isinstance(status, (str, unicode)):
elif status > worst:
worst = status
worst_field = str(field.struct_name) + '.' + str(
if worst > 255 or checks:
yield '\n/* Check that field information fits in pb_field_t */\n'
if worst > 65535 or checks:
yield '#if !defined(PB_FIELD_32BIT)\n'
if worst > 65535:
yield '#error Field descriptor for %s is too large. Define PB_FIELD_32BIT to fix this.\n' % worst_field
assertion = ' && '.join(str(c) + ' < 65536' for c in checks)
msgs = '_'.join(str(n) for n in checks_msgnames)
yield '/* If you get an error here, it means that you need to define PB_FIELD_32BIT\n'
yield ' * compile-time option. You can do that in pb.h or on compiler command line.\n'
yield ' * \n'
yield ' * The reason you need to do this is that some of your messages contain tag\n'
yield ' * numbers or field sizes that are larger than what can fit in 8 or 16 bit\n'
yield ' * field descriptors.\n'
yield ' */\n'
yield 'STATIC_ASSERT((%s), YOU_MUST_DEFINE_PB_FIELD_32BIT_FOR_MESSAGES_%s)\n'%(assertion,msgs)
yield '#endif\n\n'
if worst < 65536:
yield '#if !defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)\n'
if worst > 255:
yield '#error Field descriptor for %s is too large. Define PB_FIELD_16BIT to fix this.\n' % worst_field
assertion = ' && '.join(str(c) + ' < 256' for c in checks)
msgs = '_'.join(str(n) for n in checks_msgnames)
yield '/* If you get an error here, it means that you need to define PB_FIELD_16BIT\n'
yield ' * compile-time option. You can do that in pb.h or on compiler command line.\n'
yield ' * \n'
yield ' * The reason you need to do this is that some of your messages contain tag\n'
yield ' * numbers or field sizes that are larger than what can fit in the default\n'
yield ' * 8 bit descriptors.\n'
yield ' */\n'
yield 'STATIC_ASSERT((%s), YOU_MUST_DEFINE_PB_FIELD_16BIT_FOR_MESSAGES_%s)\n'%(assertion,msgs)
yield '#endif\n\n'
# Add check for sizeof(double)
has_double = False
for msg in messages:
for field in msg.fields:
if field.ctype == 'double':
has_double = True
if has_double:
yield '\n'
yield '/* On some platforms (such as AVR), double is really float.\n'
yield ' * These are not directly supported by nanopb, but see example_avr_double.\n'
yield ' * To get rid of this error, remove any double fields from your .proto.\n'
yield ' */\n'
yield 'STATIC_ASSERT(sizeof(double) == 8, DOUBLE_MUST_BE_8_BYTES)\n'
yield '\n'
# ---------------------------------------------------------------------------
# Options parsing for the .proto files
# ---------------------------------------------------------------------------
from fnmatch import fnmatch
def read_options_file(infile):
'''Parse a separate options file to list:
[(namemask, options), ...]
results = []
for line in infile:
line = line.strip()
if not line or line.startswith('//') or line.startswith('#'):
parts = line.split(None, 1)
opts = nanopb_pb2.NanoPBOptions()
text_format.Merge(parts[1], opts)
results.append((parts[0], opts))
return results
class Globals:
'''Ugly global variables, should find a good way to pass these.'''
verbose_options = False
separate_options = []
matched_namemasks = set()
def get_nanopb_suboptions(subdesc, options, name):
'''Get copy of options, and merge information from subdesc.'''
new_options = nanopb_pb2.NanoPBOptions()
# Handle options defined in a separate file
dotname = '.'.join(
for namemask, options in Globals.separate_options:
if fnmatch(dotname, namemask):
# Handle options defined in .proto
if isinstance(subdesc.options, descriptor.FieldOptions):
ext_type = nanopb_pb2.nanopb
elif isinstance(subdesc.options, descriptor.FileOptions):
ext_type = nanopb_pb2.nanopb_fileopt
elif isinstance(subdesc.options, descriptor.MessageOptions):
ext_type = nanopb_pb2.nanopb_msgopt
elif isinstance(subdesc.options, descriptor.EnumOptions):
ext_type = nanopb_pb2.nanopb_enumopt
raise Exception("Unknown options type")
if subdesc.options.HasExtension(ext_type):
ext = subdesc.options.Extensions[ext_type]
if Globals.verbose_options:
sys.stderr.write("Options for " + dotname + ": ")
sys.stderr.write(text_format.MessageToString(new_options) + "\n")
return new_options
# ---------------------------------------------------------------------------
# Command line interface
# ---------------------------------------------------------------------------
import sys
import os.path
from optparse import OptionParser
optparser = OptionParser(
usage = "Usage: [options] file.pb ...",
epilog = "Compile file.pb from file.proto by: 'protoc -ofile.pb file.proto'. " +
"Output will be written to file.pb.h and file.pb.c.")
optparser.add_option("-x", dest="exclude", metavar="FILE", action="append", default=[],
help="Exclude file from generated #include list.")
optparser.add_option("-e", "--extension", dest="extension", metavar="EXTENSION", default=".pb",
help="Set extension to use instead of '.pb' for generated files. [default: %default]")
optparser.add_option("-f", "--options-file", dest="options_file", metavar="FILE", default="%s.options",
help="Set name of a separate generator options file.")
optparser.add_option("-Q", "--generated-include-format", dest="genformat",
metavar="FORMAT", default='#include "%s"\n',
help="Set format string to use for including other .pb.h files. [default: %default]")
optparser.add_option("-L", "--library-include-format", dest="libformat",
metavar="FORMAT", default='#include <%s>\n',
help="Set format string to use for including the nanopb pb.h header. [default: %default]")
optparser.add_option("-T", "--no-timestamp", dest="notimestamp", action="store_true", default=False,
help="Don't add timestamp to .pb.h and .pb.c preambles")
optparser.add_option("-q", "--quiet", dest="quiet", action="store_true", default=False,
help="Don't print anything except errors.")
optparser.add_option("-v", "--verbose", dest="verbose", action="store_true", default=False,
help="Print more information.")
optparser.add_option("-s", dest="settings", metavar="OPTION:VALUE", action="append", default=[],
help="Set generator option (max_size, max_count etc.).")
def process_file(filename, fdesc, options):
'''Process a single file.
filename: The full path to the .proto or .pb source file, as string.
fdesc: The loaded FileDescriptorSet, or None to read from the input file.
options: Command line options as they come from OptionsParser.
Returns a dict:
{'headername': Name of header file,
'headerdata': Data for the .h header file,
'sourcename': Name of the source code file,
'sourcedata': Data for the .c source code file
toplevel_options = nanopb_pb2.NanoPBOptions()
for s in options.settings:
text_format.Merge(s, toplevel_options)
if not fdesc:
data = open(filename, 'rb').read()
fdesc = descriptor.FileDescriptorSet.FromString(data).file[0]
# Check if there is a separate .options file
had_abspath = False
optfilename = options.options_file % os.path.splitext(filename)[0]
except TypeError:
# No %s specified, use the filename as-is
optfilename = options.options_file
had_abspath = True
if os.path.isfile(optfilename):
if options.verbose:
sys.stderr.write('Reading options from ' + optfilename + '\n')
Globals.separate_options = read_options_file(open(optfilename, "rU"))
# If we are given a full filename and it does not exist, give an error.
# However, don't give error when we automatically look for .options file
# with the same name as .proto.
if options.verbose or had_abspath:
sys.stderr.write('Options file not found: ' + optfilename)
Globals.separate_options = []
Globals.matched_namemasks = set()
# Parse the file
file_options = get_nanopb_suboptions(fdesc, toplevel_options, Names([filename]))
enums, messages, extensions = parse_file(fdesc, file_options)
# Decide the file names
noext = os.path.splitext(filename)[0]
headername = noext + options.extension + '.h'
sourcename = noext + options.extension + '.c'
headerbasename = os.path.basename(headername)
# List of .proto files that should not be included in the C header file
# even if they are mentioned in the source .proto.
excludes = ['nanopb.proto', 'google/protobuf/descriptor.proto'] + options.exclude
dependencies = [d for d in fdesc.dependency if d not in excludes]
headerdata = ''.join(generate_header(dependencies, headerbasename, enums,
messages, extensions, options))
sourcedata = ''.join(generate_source(headerbasename, enums,
messages, extensions, options))
# Check if there were any lines in .options that did not match a member
unmatched = [n for n,o in Globals.separate_options if n not in Globals.matched_namemasks]
if unmatched and not options.quiet:
sys.stderr.write("Following patterns in " + optfilename + " did not match any fields: "
+ ', '.join(unmatched) + "\n")
if not Globals.verbose_options:
sys.stderr.write("Use protoc --nanopb-out=-v:. to see a list of the field names.\n")
return {'headername': headername, 'headerdata': headerdata,
'sourcename': sourcename, 'sourcedata': sourcedata}
def main_cli():
'''Main function when invoked directly from the command line.'''
options, filenames = optparser.parse_args()
if not filenames:
if options.quiet:
options.verbose = False
Globals.verbose_options = options.verbose
for filename in filenames:
results = process_file(filename, None, options)
if not options.quiet:
sys.stderr.write("Writing to " + results['headername'] + " and "
+ results['sourcename'] + "\n")
open(results['headername'], 'w').write(results['headerdata'])
open(results['sourcename'], 'w').write(results['sourcedata'])
def main_plugin():
'''Main function when invoked as a protoc plugin.'''
import sys
if sys.platform == "win32":
import os, msvcrt
# Set stdin and stdout to binary mode
msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
data =
request = plugin_pb2.CodeGeneratorRequest.FromString(data)
import shlex
args = shlex.split(request.parameter)
options, dummy = optparser.parse_args(args)
Globals.verbose_options = options.verbose
response = plugin_pb2.CodeGeneratorResponse()
for filename in request.file_to_generate:
for fdesc in request.proto_file:
if == filename:
results = process_file(filename, fdesc, options)
f = response.file.add() = results['headername']
f.content = results['headerdata']
f = response.file.add() = results['sourcename']
f.content = results['sourcedata']
if __name__ == '__main__':
# Check if we are running as a plugin under protoc
if 'protoc-gen-' in sys.argv[0] or '--protoc-plugin' in sys.argv: