Adds support for the LITE_RUNTIME optimization option to the protobuf-c
compiler. Enabling this option would generate lighter weight message,
enum, and service descriptors that contain NO strings. As a result,
calls to lookup descriptors via the *_get_{field,value,method}_by_name
API will return NULL.
Default compiler behavior (when optimize_for is not specified or is not
set to LITE_RUNTIME) is unchanged.
identifiers that begin with an underscore are reserved. instead, use a
double underscore in the *middle* of the identifier to indicate that
it's an "internal" identifier.
there is some confusion with regard to the use of lower case letters in
enum values. take the following message definition:
message LowerCase {
enum CaseEnum {
UPPER = 1;
lower = 2;
}
optional CaseEnum value = 1 [default = lower];
}
this generates the following C enum:
typedef enum _LowerCase__CaseEnum {
LOWER_CASE__CASE_ENUM__UPPER = 1,
LOWER_CASE__CASE_ENUM__lower = 2
_PROTOBUF_C_FORCE_ENUM_TO_BE_INT_SIZE(LOWER_CASE__CASE_ENUM)
} LowerCase__CaseEnum;
note that the case of the enum value 'lower' was preserved in the C
symbol name as 'LOWER_CASE__CASE_ENUM__lower', but that the _INIT macro
references the same enum value with the (non-existent) C symbol name
'LOWER_CASE__CASE_ENUM__LOWER':
#define LOWER_CASE__INIT \
{ PROTOBUF_C_MESSAGE_INIT (&lower_case__descriptor) \
, 0,LOWER_CASE__CASE_ENUM__LOWER }
additionally, the ProtobufCEnumValue array generated also refers to the
same enum value with the (non-existent) upper cased version:
const ProtobufCEnumValue lower_case__case_enum__enum_values_by_number[2] =
{
{ "UPPER", "LOWER_CASE__CASE_ENUM__UPPER", 1 },
{ "lower", "LOWER_CASE__CASE_ENUM__LOWER", 2 },
};
we should preserve the existing behavior of copying the case from the
enum values in the message definition and fix up the places where the
(non-existent) upper case version is used, rather than changing the enum
definition itself to match the case used in the _INIT macro and
enum_values_by_number array, because it's possible that there might be
existing working code that uses enum values with lower case letters that
would be affected by such a change.
incidentally, google's C++ protobuf implementation preserves case in
enum values. protoc --cpp_out generates the following enum declaration
for the message descriptor above:
enum LowerCase_CaseEnum {
LowerCase_CaseEnum_UPPER = 1,
LowerCase_CaseEnum_lower = 2
};
per https://code.google.com/p/protobuf/source/detail?r=50, the license
on google-originated protobuf code was switched from Apache-2.0 to
BSD-3-Clause (so-called "New BSD" license). update any of the google
license statements to use this new license.
per email with dave, drop the third clause on his BSD-3-Clause license,
so this now becomes BSD-2-Clause.
make sure to use consistent indentation and wrapping throughout.
