foundationdb/flow/flat_buffers.cpp

489 lines
13 KiB
C++

/*
* flat_buffers.cpp
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "flow/flat_buffers.h"
#include "flow/UnitTest.h"
#include "flow/Arena.h"
#include "flow/serialize.h"
#include "flow/ObjectSerializer.h"
#include <algorithm>
#include <iomanip>
#include <variant>
namespace detail {
namespace {
std::vector<int> mWriteToOffsetsMemoy;
}
std::vector<int>* writeToOffsetsMemory = &mWriteToOffsetsMemoy;
VTable generate_vtable(size_t numMembers, const std::vector<unsigned>& sizesAlignments) {
if (numMembers == 0) {
return VTable{ 4, 4 };
}
// first is index, second is size
std::vector<std::pair<unsigned, unsigned>> indexed;
indexed.reserve(numMembers);
for (unsigned i = 0; i < numMembers; ++i) {
if (sizesAlignments[i] > 0) {
indexed.emplace_back(i, sizesAlignments[i]);
}
}
std::stable_sort(indexed.begin(), indexed.end(),
[](const std::pair<unsigned, unsigned>& lhs, const std::pair<unsigned, unsigned>& rhs) {
return lhs.second > rhs.second;
});
VTable result;
result.resize(numMembers + 2);
// size of the vtable is
// - 2 bytes per member +
// - 2 bytes for the size entry +
// - 2 bytes for the size of the object
result[0] = 2 * numMembers + 4;
int offset = 0;
for (auto p : indexed) {
auto align = sizesAlignments[numMembers + p.first];
auto& res = result[p.first + 2];
res = offset % align == 0 ? offset : ((offset / align) + 1) * align;
offset = res + p.second;
res += 4;
}
result[1] = offset + 4;
return result;
}
} // namespace detail
namespace unit_tests {
TEST_CASE("flow/FlatBuffers/test") {
auto* vtable1 = detail::get_vtable<int>();
auto* vtable2 = detail::get_vtable<uint8_t, uint8_t, int, int64_t, int>();
auto* vtable3 = detail::get_vtable<uint8_t, uint8_t, int, int64_t, int>();
auto* vtable4 = detail::get_vtable<uint32_t>();
ASSERT(vtable1 != vtable2);
ASSERT(vtable2 == vtable3);
ASSERT(vtable1 == vtable4); // Different types, but same vtable! Saves space in encoded messages
ASSERT(vtable1->size() == 3);
ASSERT(vtable2->size() == 7);
ASSERT((*vtable2)[0] == 14);
ASSERT((*vtable2)[1] == 22);
ASSERT(((*vtable2)[4] - 4) % 4 == 0);
ASSERT(((*vtable2)[5] - 4) % 8 == 0);
ASSERT(((*vtable2)[6] - 4) % 4 == 0);
return Void();
}
TEST_CASE("flow/FlatBuffers/emptyVtable") {
auto* vtable = detail::get_vtable<>();
ASSERT((*vtable)[0] == 4);
ASSERT((*vtable)[1] == 4);
return Void();
}
struct Table2 {
std::string m_p = {};
bool m_ujrnpumbfvc = {};
int64_t m_iwgxxt = {};
int64_t m_tjkuqo = {};
int16_t m_ed = {};
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, m_p, m_ujrnpumbfvc, m_iwgxxt, m_tjkuqo, m_ed);
}
};
struct Table3 {
uint16_t m_asbehdlquj = {};
uint16_t m_k = {};
uint16_t m_jib = {};
int64_t m_n = {};
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, m_asbehdlquj, m_k, m_jib, m_n);
}
};
TEST_CASE("flow/FlatBuffers/vtable2") {
const auto& vtable =
*detail::get_vtable<uint64_t, bool, std::string, int64_t, std::vector<uint16_t>, Table2, Table3>();
ASSERT(!(vtable[2] <= vtable[4] && vtable[4] < vtable[2] + 8));
return Void();
}
struct Nested2 {
uint8_t a;
std::vector<std::string> b;
int c;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a, b, c);
}
friend bool operator==(const Nested2& lhs, const Nested2& rhs) {
return lhs.a == rhs.a && lhs.b == rhs.b && lhs.c == rhs.c;
}
};
struct Nested {
uint8_t a;
std::string b;
Nested2 nested;
std::vector<uint64_t> c;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a, b, nested, c);
}
};
struct Root {
uint8_t a;
std::vector<Nested2> b;
Nested c;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a, b, c);
}
};
struct TestContextArena {
Arena& _arena;
Arena& arena() { return _arena; }
ProtocolVersion protocolVersion() const { return currentProtocolVersion; }
uint8_t* allocate(size_t size) { return new (_arena) uint8_t[size]; }
};
TEST_CASE("flow/FlatBuffers/collectVTables") {
Root root;
Arena arena;
TestContextArena context{ arena };
const auto* vtables = detail::get_vtableset(root, context);
ASSERT(vtables == detail::get_vtableset(root, context));
const auto& root_vtable = *detail::get_vtable<uint8_t, std::vector<Nested2>, Nested>();
const auto& nested_vtable = *detail::get_vtable<uint8_t, std::vector<std::string>, int>();
int root_offset = vtables->getOffset(&root_vtable);
int nested_offset = vtables->getOffset(&nested_vtable);
ASSERT(!memcmp((uint8_t*)&root_vtable[0], &vtables->packed_tables[root_offset], root_vtable.size()));
ASSERT(!memcmp((uint8_t*)&nested_vtable[0], &vtables->packed_tables[nested_offset], nested_vtable.size()));
return Void();
}
void print_buffer(const uint8_t* out, int len) {
std::cout << std::hex << std::setfill('0');
for (int i = 0; i < len; ++i) {
if (i % 8 == 0) {
std::cout << std::endl;
std::cout << std::setw(4) << i << ": ";
}
std::cout << std::setw(2) << (int)out[i] << " ";
}
std::cout << std::endl << std::dec;
}
struct Arena {
std::vector<std::pair<uint8_t*, size_t>> allocated;
~Arena() {
for (auto b : allocated) {
delete[] b.first;
}
}
uint8_t* operator()(size_t sz) {
auto res = new uint8_t[sz];
allocated.emplace_back(res, sz);
return res;
}
size_t get_size(const uint8_t* ptr) const {
for (auto& p : allocated) {
if (p.first == ptr) {
return p.second;
}
}
return -1;
}
};
struct TestContext {
Arena& _arena;
Arena& arena() { return _arena; }
ProtocolVersion protocolVersion() const { return currentProtocolVersion; }
uint8_t* allocate(size_t size) { return _arena(size); }
TestContext& context() { return *this; }
};
TEST_CASE("flow/FlatBuffers/serializeDeserializeRoot") {
Root root{ 1,
{ { 13, { "ghi", "jkl" }, 15 }, { 16, { "mnop", "qrstuv" }, 18 } },
{ 3, "hello", { 6, { "abc", "def" }, 8 }, { 10, 11, 12 } } };
Root root2 = root;
Arena arena;
TestContext context{ arena };
auto out = detail::save(context, root, FileIdentifier{});
ASSERT(root.a == root2.a);
ASSERT(root.b == root2.b);
ASSERT(root.c.a == root2.c.a);
ASSERT(root.c.b == root2.c.b);
ASSERT(root.c.nested.a == root2.c.nested.a);
ASSERT(root.c.nested.b == root2.c.nested.b);
ASSERT(root.c.nested.c == root2.c.nested.c);
ASSERT(root.c.c == root2.c.c);
root2 = {};
detail::load(root2, out, context);
ASSERT(root.a == root2.a);
ASSERT(root.b == root2.b);
ASSERT(root.c.a == root2.c.a);
ASSERT(root.c.b == root2.c.b);
ASSERT(root.c.nested.a == root2.c.nested.a);
ASSERT(root.c.nested.b == root2.c.nested.b);
ASSERT(root.c.nested.c == root2.c.nested.c);
ASSERT(root.c.c == root2.c.c);
return Void();
}
TEST_CASE("flow/FlatBuffers/serializeDeserializeMembers") {
Root root{ 1,
{ { 13, { "ghi", "jkl" }, 15 }, { 16, { "mnop", "qrstuv" }, 18 } },
{ 3, "hello", { 6, { "abc", "def" }, 8 }, { 10, 11, 12 } } };
Root root2 = root;
Arena arena;
TestContext context{arena};
const auto* out = save_members(context, FileIdentifier{}, root.a, root.b, root.c);
ASSERT(root.a == root2.a);
ASSERT(root.b == root2.b);
ASSERT(root.c.a == root2.c.a);
ASSERT(root.c.b == root2.c.b);
ASSERT(root.c.nested.a == root2.c.nested.a);
ASSERT(root.c.nested.b == root2.c.nested.b);
ASSERT(root.c.nested.c == root2.c.nested.c);
ASSERT(root.c.c == root2.c.c);
root2 = {};
load_members(out, context, root2.a, root2.b, root2.c);
ASSERT(root.a == root2.a);
ASSERT(root.b == root2.b);
ASSERT(root.c.a == root2.c.a);
ASSERT(root.c.b == root2.c.b);
ASSERT(root.c.nested.a == root2.c.nested.a);
ASSERT(root.c.nested.b == root2.c.nested.b);
ASSERT(root.c.nested.c == root2.c.nested.c);
ASSERT(root.c.c == root2.c.c);
return Void();
}
} // namespace unit_tests
namespace unit_tests {
TEST_CASE("flow/FlatBuffers/variant") {
using V = boost::variant<int, double, Nested2>;
V v1;
V v2;
Arena arena;
TestContext context{arena};
const uint8_t* out;
v1 = 1;
out = save_members(context, FileIdentifier{}, v1);
// print_buffer(out, arena.get_size(out));
load_members(out, context, v2);
ASSERT(boost::get<int>(v1) == boost::get<int>(v2));
v1 = 1.0;
out = save_members(context, FileIdentifier{}, v1);
// print_buffer(out, arena.get_size(out));
load_members(out, context, v2);
ASSERT(boost::get<double>(v1) == boost::get<double>(v2));
v1 = Nested2{ 1, { "abc", "def" }, 2 };
out = save_members(context, FileIdentifier{}, v1);
// print_buffer(out, arena.get_size(out));
load_members(out, context, v2);
ASSERT(boost::get<Nested2>(v1).a == boost::get<Nested2>(v2).a);
ASSERT(boost::get<Nested2>(v1).b == boost::get<Nested2>(v2).b);
ASSERT(boost::get<Nested2>(v1).c == boost::get<Nested2>(v2).c);
return Void();
}
TEST_CASE("flow/FlatBuffers/vectorBool") {
std::vector<bool> x1 = { true, false, true, false, true };
std::vector<bool> x2;
Arena arena;
TestContext context{arena};
const uint8_t* out;
out = save_members(context, FileIdentifier{}, x1);
// print_buffer(out, arena.get_size(out));
load_members(out, context, x2);
ASSERT(x1 == x2);
return Void();
}
} // namespace unit_tests
namespace unit_tests {
struct Y1 {
int a;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a);
}
};
struct Y2 {
int a;
boost::variant<int> b;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a, b);
}
};
template <class Y>
struct X {
int a;
Y b;
int c;
template <class Archiver>
void serialize(Archiver& ar) {
serializer(ar, a, b, c);
}
};
TEST_CASE("/flow/FlatBuffers/nestedCompat") {
X<Y1> x1 = { 1, { 2 }, 3 };
X<Y2> x2;
Arena arena;
TestContext context{arena};
const uint8_t* out;
out = save_members(context, FileIdentifier{}, x1);
load_members(out, context, x2);
ASSERT(x1.a == x2.a);
ASSERT(x1.b.a == x2.b.a);
ASSERT(x1.c == x2.c);
x1 = {};
x2.b.b = 4;
out = save_members(context, FileIdentifier{}, x2);
load_members(out, context, x1);
ASSERT(x1.a == x2.a);
ASSERT(x1.b.a == x2.b.a);
ASSERT(x1.c == x2.c);
return Void();
}
TEST_CASE("/flow/FlatBuffers/struct") {
std::vector<std::tuple<int16_t, bool, int64_t>> x1 = { { 1, true, 2 }, { 3, false, 4 } };
decltype(x1) x2;
Arena arena;
TestContext context{arena };
const uint8_t* out;
out = save_members(context, FileIdentifier{}, x1);
// print_buffer(out, arena.get_size(out));
load_members(out, context, x2);
ASSERT(x1 == x2);
return Void();
}
TEST_CASE("/flow/FlatBuffers/file_identifier") {
Arena arena;
TestContext context{arena};
const uint8_t* out;
constexpr FileIdentifier file_identifier{ 1234 };
Y1 y1;
out = save_members(context, file_identifier, y1);
// print_buffer(out, arena.get_size(out));
ASSERT(read_file_identifier(out) == file_identifier);
return Void();
}
TEST_CASE("/flow/FlatBuffers/VectorRef") {
// this test tests a few weird memory properties of
// serialized arenas. This is why it uses weird scoping
// first we construct the data to serialize/deserialize
// so we can compare it afterwards
std::vector<std::string> src;
src.push_back("Foo");
src.push_back("Bar");
::Arena vecArena;
VectorRef<StringRef> outVec;
{
::Arena readerArena;
StringRef serializedVector;
{
::Arena arena;
VectorRef<StringRef> vec;
for (const auto& str : src) {
vec.push_back(arena, str);
}
ObjectWriter writer(Unversioned());
writer.serialize(FileIdentifierFor<decltype(vec)>::value, arena, vec);
serializedVector = StringRef(readerArena, writer.toStringRef());
}
ArenaObjectReader reader(readerArena, serializedVector, Unversioned());
// The VectorRef and Arena arguments are intentionally in a different order from the serialize call above.
// Arenas need to get serialized after any Ref types whose memory they own. In order for schema evolution to be
// possible, it needs to be okay to reorder an Arena so that it appears after a newly added Ref type. For this
// reason, Arenas are ignored by the wire protocol entirely. We test that behavior here.
reader.deserialize(FileIdentifierFor<decltype(outVec)>::value, outVec, vecArena);
}
ASSERT(src.size() == outVec.size());
for (int i = 0; i < src.size(); ++i) {
auto str = outVec[i].toString();
ASSERT(str == src[i]);
}
return Void();
}
TEST_CASE("/flow/FlatBuffers/Standalone") {
Standalone<VectorRef<StringRef>> vecIn;
auto numElements = deterministicRandom()->randomInt(1, 20);
for (int i = 0; i < numElements; ++i) {
auto str = deterministicRandom()->randomAlphaNumeric(deterministicRandom()->randomInt(0, 30));
vecIn.push_back(vecIn.arena(), StringRef(vecIn.arena(), str));
}
Standalone<StringRef> value = ObjectWriter::toValue(vecIn, Unversioned());
ArenaObjectReader reader(value.arena(), value, Unversioned());
VectorRef<Standalone<StringRef>> vecOut;
reader.deserialize(vecOut);
ASSERT(vecOut.size() == vecIn.size());
for (int i = 0; i < vecOut.size(); ++i) {
ASSERT(vecOut[i] == vecIn[i]);
}
return Void();
}
} // namespace unit_tests