d2658e25fe
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
};
Overview
This is protobuf-c, a C implementation of Google Protocol Buffers. It includes libprotobuf-c, a pure C library that implements protobuf encoding and decoding, and protoc-c, a code generator that converts Protocol Buffer .proto files to C descriptor code, based on the original protoc. protobuf-c formerly included an RPC implementation; that code has been split out into the protobuf-c-rpc project.
protobuf-c was originally maintained by Dave Benson through version 0.15 but is now being maintained by a new team. Thanks, Dave!
Building
protobuf-c requires a C compiler, a C++ compiler, Google Protocol Buffers, and pkg-config to be installed.
./configure && make && make install
If building from a git checkout, the autotools (autoconf, automake, libtool) must also be installed, and the build system must be generated by running the autogen.sh script.
./autogen.sh && ./configure && make && make install
Synopsis
Include the protobuf-c header file:
#include <protobuf-c/protobuf-c.h>
Link against the protobuf-c library.
-lprotobuf-c
libprotobuf-c includes a pkg-config file. It is recommended to use the pkg-config system in order to determine the complete set of compiler and linker flags for building applications that utilize libprotobuf-c. If using pkg-config with autoconf, the PKG_CHECK_MODULES macro can be used to detect the presence of libprotobuf-c:
PKG_CHECK_MODULES([PROTOBUF_C], [libprotobuf-c])
This will place compiler flags in the PROTOBUF_C_CFLAGS variable and linker flags in the PROTOBUF_C_LDFLAGS variable.
(Note that the protobuf-c header file used to be installed as google/protobuf-c/protobuf-c.h in previous versions.)
Contributing
Please send patches to the protobuf-c mailing list or by opening a GitHub pull request.
Copyright to all contributions are retained by the original author, but must be licensed under the terms of the BSD-2-Clause license. Please add a Signed-off-by header to your commit message (git commit -s) to indicate that you are licensing your contribution under these terms.