Speedups: remove dependency on c++ (#2796)

* Speedups: remove dependency on c++

* Speedups: intset: handle malloc failing

* Speedups: intset: fix corner case for int64 on 32bit systems

original idea was to only use bucket->val if int<pointer,
but we always have a union now anyway

* Speedups: add size comment to player_set bucket configuration

* test: more tests for LocationStore.find_item

* test: require _speedups in CI

This kind of tests that the build succeeds.

* test: even more tests for LocationStore.find_item

* Speedups: intset uniform comment style

* Speedups: intset: avoid memory leak when realloc fails

* Speedups: intset: make `gcc -pedantic -std=c99 -fanalyzer` without warnings

Unnamed unions are not in C99, this got fixed.
The overhead of setting count=0 is minimal or optimized-out and silences -fanalizer (see comment).

* Speedups: don't leak memory in case of exception

* Speedups: intset: validate alloc and free

This won't happen in our cython, but it's still a good addition.

* CI: add test framework for C/C++ code

* CI: ctest: fix cwd

* Speedups: intset: ignore msvc warning

* Tests: intset: revert attempt at no-asan

We solve this with env vars in ctest now, and this fails for msvc.

* Test: cpp: docs: fix typo

* Test: cpp: docs: fix another typo

* Test: intset: proper bucket count for Negative test

INTxx_MIN % 1 would not produce a negative number, so the test was flawed.

test/cpp/CMakeLists.txt

@@ -0,0 +1,49 @@
+cmake_minimum_required(VERSION 3.5)
+project(ap-cpp-tests)
+
+enable_testing()
+
+find_package(GTest REQUIRED)
+
+if (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
+    add_definitions("/source-charset:utf-8")
+    set(CMAKE_CXX_FLAGS_DEBUG "/MTd")
+    set(CMAKE_CXX_FLAGS_RELEASE "/MT")
+elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+    # enable static analysis for gcc
+    add_compile_options(-fanalyzer -Werror)
+    # disable stuff that gets triggered by googletest
+    add_compile_options(-Wno-analyzer-malloc-leak)
+    # enable asan for gcc
+    add_compile_options(-fsanitize=address)
+    add_link_options(-fsanitize=address)
+endif ()
+
+add_executable(test_default)
+
+target_include_directories(test_default
+        PRIVATE
+        ${GTEST_INCLUDE_DIRS}
+)
+
+target_link_libraries(test_default
+        ${GTEST_BOTH_LIBRARIES}
+)
+
+add_test(
+        NAME test_default
+        COMMAND  test_default
+)
+
+set_property(
+        TEST test_default
+        PROPERTY ENVIRONMENT "ASAN_OPTIONS=allocator_may_return_null=1"
+)
+
+file(GLOB ITEMS *)
+foreach(item ${ITEMS})
+    if(IS_DIRECTORY ${item} AND EXISTS ${item}/CMakeLists.txt)
+        message(${item})
+        add_subdirectory(${item})
+    endif()
+endforeach()

test/cpp/README.md

@@ -0,0 +1,32 @@
+# C++ tests
+
+Test framework for C and C++ code in AP.
+
+## Adding a Test
+
+### GoogleTest
+
+Adding GoogleTests is as simple as creating a directory with
+* one or more `test_*.cpp` files that define tests using
+  [GoogleTest API](https://google.github.io/googletest/)
+* a `CMakeLists.txt` that adds the .cpp files to `test_default` target using
+  [target_sources](https://cmake.org/cmake/help/latest/command/target_sources.html)
+
+### CTest
+
+If either GoogleTest is not suitable for the test or the build flags / sources / libraries are incompatible,
+you can add another CTest to the project using add_target and add_test, similar to how it's done for `test_default`.
+
+## Running Tests
+
+* Install [CMake](https://cmake.org/).
+* Build and/or install GoogleTest and make sure
+  [CMake can find it](https://cmake.org/cmake/help/latest/module/FindGTest.html), or
+  [create a parent `CMakeLists.txt` that fetches GoogleTest](https://google.github.io/googletest/quickstart-cmake.html).
+* Enter the directory with the top-most `CMakeLists.txt` and run
+  ```sh
+  mkdir build
+  cmake -S . -B build/ -DCMAKE_BUILD_TYPE=Release
+  cmake --build build/ --config Release && \
+  ctest --test-dir build/ -C Release --output-on-failure
+  ```

test/cpp/intset/CMakeLists.txt

@@ -0,0 +1,4 @@
+target_sources(test_default
+        PRIVATE
+        ${CMAKE_CURRENT_SOURCE_DIR}/test_intset.cpp
+)

test/cpp/intset/test_intset.cpp

@@ -0,0 +1,105 @@
+#include <limits>
+#include <cstdint>
+#include <gtest/gtest.h>
+
+// uint32Set
+#define INTSET_NAME uint32Set
+#define INTSET_TYPE uint32_t
+#include "../../../intset.h"
+#undef INTSET_NAME
+#undef INTSET_TYPE
+
+// int64Set
+#define INTSET_NAME int64Set
+#define INTSET_TYPE int64_t
+#include "../../../intset.h"
+
+
+TEST(IntsetTest, ZeroBuckets)
+{
+    // trying to allocate with zero buckets has to either fail or be functioning
+    uint32Set *set = uint32Set_new(0);
+    if (!set)
+        return; // failed -> OK
+
+    EXPECT_FALSE(uint32Set_contains(set, 1));
+    EXPECT_TRUE(uint32Set_add(set, 1));
+    EXPECT_TRUE(uint32Set_contains(set, 1));
+    uint32Set_free(set);
+}
+
+TEST(IntsetTest, Duplicate)
+{
+    // adding the same number again can't fail
+    uint32Set *set = uint32Set_new(2);
+    ASSERT_TRUE(set);
+    EXPECT_TRUE(uint32Set_add(set, 0));
+    EXPECT_TRUE(uint32Set_add(set, 0));
+    EXPECT_TRUE(uint32Set_contains(set, 0));
+    uint32Set_free(set);
+}
+
+TEST(IntsetTest, SetAllocFailure)
+{
+    // try to allocate 100TB of RAM, should fail and return NULL
+    if (sizeof(size_t) < 8)
+        GTEST_SKIP() << "Alloc error not testable on 32bit";
+    int64Set *set = int64Set_new(6250000000000ULL);
+    EXPECT_FALSE(set);
+    int64Set_free(set);
+}
+
+TEST(IntsetTest, SetAllocOverflow)
+{
+    // try to overflow argument passed to malloc
+    int64Set *set = int64Set_new(std::numeric_limits<size_t>::max());
+    EXPECT_FALSE(set);
+    int64Set_free(set);
+}
+
+TEST(IntsetTest, NullFree)
+{
+    // free(NULL) should not try to free buckets
+    uint32Set_free(NULL);
+    int64Set_free(NULL);
+}
+
+TEST(IntsetTest, BucketRealloc)
+{
+    // add a couple of values to the same bucket to test growing the bucket
+    uint32Set* set = uint32Set_new(1);
+    ASSERT_TRUE(set);
+    EXPECT_FALSE(uint32Set_contains(set, 0));
+    EXPECT_TRUE(uint32Set_add(set, 0));
+    EXPECT_TRUE(uint32Set_contains(set, 0));
+    for (uint32_t i = 1; i < 32; ++i) {
+        EXPECT_TRUE(uint32Set_add(set, i));
+        EXPECT_TRUE(uint32Set_contains(set, i - 1));
+        EXPECT_TRUE(uint32Set_contains(set, i));
+        EXPECT_FALSE(uint32Set_contains(set, i + 1));
+    }
+    uint32Set_free(set);
+}
+
+TEST(IntSet, Max)
+{
+    constexpr auto n = std::numeric_limits<uint32_t>::max();
+    uint32Set *set = uint32Set_new(1);
+    ASSERT_TRUE(set);
+    EXPECT_FALSE(uint32Set_contains(set, n));
+    EXPECT_TRUE(uint32Set_add(set, n));
+    EXPECT_TRUE(uint32Set_contains(set, n));
+    uint32Set_free(set);
+}
+
+TEST(InsetTest, Negative)
+{
+    constexpr auto n = std::numeric_limits<int64_t>::min();
+    static_assert(n < 0, "n not negative");
+    int64Set *set = int64Set_new(3);
+    ASSERT_TRUE(set);
+    EXPECT_FALSE(int64Set_contains(set, n));
+    EXPECT_TRUE(int64Set_add(set, n));
+    EXPECT_TRUE(int64Set_contains(set, n));
+    int64Set_free(set);
+}