Prior to this commit the default C++ code generator was `c++0x`.
A code generated with `c++0x` code-gen might have a vulnerability (undefined behavior) connected evolution of enums in a schema. This UB could break the backward compatibility if previously generated code casts an unknown enumerator to enum type that knows nothing about future enumerators added to the schema.
The main differences between `c++0x` and `c++11`:
- generated enums use explicitly declared underlying type;
- generated object-API tables don't declare default ctor() explicitly, instead of it default data member initializers are generated.
Please use `flatc --cpp-std c++0x` option for backward compatibility with old compilers.
UnpackTo copies vector elements one-by-one, which can be very inefficient depending on the quality of the compiler optimizations performed. This change updates the operation for vectors of bytes that aren't enums to use 'std::copy', which is usually highly optimized.
vectors of types that are more than one byte can't be optimized in this way because of the endianness of the serialized bytes vs. the target architecture endianness.
vectors of enums can't be optimized because they are required to be static_cast into the appropriate enum type when stored in the vector.
vectors of bools can be optimized in most cases, but since the standard
allows std::vector<bool> template specialization for space-savings,
std::copy doesn't work on every implementation (looking at you
Microsoft). Thus, this optimization is skipped for vector<bool>.
For a specific example, this improves the latency of unpacking large buffers on the Hexagon DSP by about 10x.
Co-authored-by: Matthew Markwell <markwell@google.com>
For example:
include/flatbuffers/reflection.h:365:8: error: definition of implicit copy
constructor for 'pointer_inside_vector<flatbuffers::Table, unsigned char>'
is deprecated because it has a user-declared copy assignment operator
[-Werror,-Wdeprecated-copy]
void operator=(const pointer_inside_vector &piv);
^
It's unclear why the old code wanted to declare a public `operator=`
without defining it; that just seems like a misunderstanding of the C++03 idiom
for deleting a member function. And anyway, we don't *want* to delete the
assignment operator; these are polymorphic types that do not follow value
semantics and nobody should ever be trying to copy them. So the simplest fix
is just to go back to the Rule of Zero: remove the declaration of `operator=`
and let the compiler do what it wanted to do originally anyway.
"The best code is no code."
Also, update the generated .h files.
Fixes#5649.
Previously UnPack would allocate data with new and assign it to a
raw pointer. This behavior makes it possible for the pointer to be
leaked in case of OOM. This commit defaults to use the user specified
pointer (which needs to implement a move constructor, a .get() and a
.release() operators), thus preventing these leaks.
* Add Builder and Table typedefs
This gives us a way to use templates to go from a builder to a table
and back again without having to pass both types in.
* Fix tests/cpp17/generated_cpp17/monster_test_generated.h
* Add flatc '--cpp_std' switch and sandbox for C++17 code generator
- Added 'flac --cpp_std legacy' for compatibility with old compilers (VS2010);
- Added experimental switch 'flac --cpp_std c++17' for future development;
- Added C++17 sandbox test_cpp17.cpp;
- C++ code generator generates enums with explicit underlying type to avoid problems with the forward and backward schema compatibility;
- Adjusted CMakeLists.txt, CI and generate code scripts to support of introduced '--cpp_std';
* Fix --cpp_std values: c++0x, c++11, c++17
* Add 'cpp::CppStandard' enum
* Add testing engine into test_cpp17
* Rebase to upstream/master
* Set default '--cpp-std C++0x'
* Fix code generation (--cpp_std C++11) in CMakeLists.txt
- Fix dependency declaration of grpctest target
* Revert --cpp-std for the tests from explicit C++11 to flatc default value (C++0x)
* Added a cpp UnPackSizePrefixed<struct_name> generated helper function
Missing helper function added to the cpp API generator for unpacking size prefixed structures
* Added generated test files
- update C++ monster_test::Color to unsigned type
- update Go Color:ubyte in the go_test.go
- add workaround for unsigned enum in java test
- sync generate.bat and generate.sh
* Fix the header file path in the tutorial doc
* Add the path field in sample/monster.fbs to match the tutorial
* Update the lobster sample file
* Update the binary sample file
Multiple calls of e.g. CreateString inside a call to a CreateTable
could cause those strings to end up in different locations in the
wire format, since order or argument evaluation is undefined.
This is allowed by the FlatBuffer format, but it is not helpful,
especially when debugging the contents of binaries, or comparing
against a "golden" binary for tests etc.
Now making sure that all the CreateTableDirect calls first serialize
sub strings/vectors before calling CreateTable.
Also made similar changes to the serialization of "binary schemas".
Change-Id: I5747c4038b37a0d400aca2bc592bec751cf5c172
Give the vtable offset enum inside each table the name
"FlatBuffersVTableOffset" and base type voffset_t so it can be used as a
dependent type in IsFieldPresent. This makes that function slightly
safer since it prevents calling it with arbitrary, non-table types.
Now, the only way to use IsFieldPresent incorrectly is to create your
own type which does not inherit from flatbuffers::Table but has a
dependent voffset convertible type "FlatBuffersVTableOffset".
Make an out-of-bounds check for enum values before using them to index the
names array. For consistency with non-sparse enums an empty string is
returned.
Fixes#4821
* Add operator== for c++ genated code
New "--gen-compare" option for flatc to generate compare operators. The operators are defined based on object based api types.
Inspired by issue #263.
* Improve compare operator for c++.
Thanks for the code review.
- Improve robustness against future schema extensions
- Code style
- Fix --rust generation in generate_code.sh
It was missing some helpers when we choose to use
size prefixed FlatBuffers.
* Add general helper : GetPrefixedSize
* Add generated helpers :
* GetSizePrefixedXXX
* VerfifySizePrefixedXXXBuffer
* FinishSizePrefixedXXXBuffer
* mini_reflect: Add DefaultTypeTable
Currently it's very easy to make a mistake when it comes to
instantiating the TypeTable to print a buffer because it is not type
safe.
This will allow us to write safer cpp code:
flatbuffers::FlatBufferToString(reinterpret_cast<const uint8_t *>(&t),
decltype(t)::DefaultTypeTable());
* c++: mini_reflect: update generated code
* Ensure types and names are set for mini_reflect
* c++: mini_refelct: update unit tests with new typed TypeTable
* Adding PR feedback of sylte and naming convention
* Add constant accessors to C++ unions
* Remove redundant const pointer return type
* Update generate_code.bat to reflect generate_code.sh
* Add updated generated files
* Remove extra space from generated code
* Update generated files
* Change directory back to tests after generating code
This is something the format supports, but none of the builders
were doing. Can save 10-20% on FlatBuffer binary size!
Also fixed the Go tests.
Change-Id: I616c56ce9bbcfcaee23aa24f0532fcb60b6a8c75
Tested: on Linux.
* Added internal - limited - implementation of flatbuffers::unique_ptr
for STLs that don't ship with std::unique_ptr. In C++11 and beyond
this is just an alias for std::unique_ptr.
* Aliased used type traits structs is_scalar is_floating_point is_unsigned
into flatbuffers namespace so they can be replaced in C++98 implementations.
Right now these point at stlport's TR1 implementations.
* Wrapped vector::data() in vector_data().
* Wrapped vector::emplace_back() in vector_emplace_back().
* Wrapper string::back() in string_back().
* Added variants of FlatBufferBuilder::CreateVector() and
FlatBufferBuilder::CreateVectorOfStructs() that allow the use of plain
function pointers.
Generated code has also been modified to use plain functions to build objects
rather than std::function() so all generated code will work in C++98
applications.
* Added flexbuffers::Builder::Vector(), flexbuffers::Builder::TypedVector()
and flexbuffers::Builder::Map() methods that allow the use of plain function
pointers.
* Changed Parser to internally use plain function pointers when parsing table
and vector delimiters.
* Added specializations of NumToString() for 64-bit types that aren't supported
by stringstream in stlport.
* Overloaded numeric_limits for 64-bit types not supported by stlport.
* Replaced build_apk.sh (which was broken by deprecation of the
"android" tool in the Android SDK) with build.gradle and the
appropriate gradle wrapper to build an APK.
* Switched Android build to build against all STL variants.
* Updated travis configuration to build Android test and sample.
Tested:
* Verified all tests continue to work on Linux, OSX and Android.
* Verified Travis build is green.
Change-Id: I9e634363793f85b9f141d21454b10686020a2065
Zero offsets are non-sensical in FlatBuffers (since offsets are
relative to themselves) but were allowed by the verifier. This could
cause buffers made up of all zeroes to be interpreted as correct
buffers with an empty root object.
Generally, not allowing such offsets will make the verifier more
likely to catch problems earlier.
Change-Id: I54010bea29721b326ff8e5348fcd9fe78e5e7506
Tested: on Linux.
Move constructors are present, which it should use instead.
This is a temp fix to make it compile, but eventually we should
generate a proper copy constructor just in-case people want to
copy objects with unions.
Tested on: Linux, OS X.
Change-Id: Idf85419995c96f5959061882157541573e306083
(C++ only for now).
Also fixed vector of union support in the object API.
Bug: 36902939
Change-Id: I935f4cc2c303a4728e26c7916a8ec0adcd6f84cb
Tested: on Linux.
* Use noexcept in union type move ctor/Add move assingment
* Add NOEXCEPT macro to deal with _MS_VER/Remove delegating ctor in union type class
* Add FLATBUFFERS_NOEXCEPT to generated union class
