P3211 Головашевич Андрей

Работает и на линуксе, и на винде. Я не осилил оригинальную организацию функций/файлов/тестов.

include/itmo/allocator.hpp

+#pragma once
+
+#include <cstddef>
+
+namespace MemoryAllocator
+{
+    class heap
+    {
+    private:
+        void *first_page = nullptr;
+    public:
+        heap();
+
+        void *malloc(size_t size);
+
+        bool free(void *block);
+    };
+}
\ No newline at end of file

os/include/itmo/mem.hpp

+#pragma once
+
+# include <cstddef>
+# include <cstdint>
+
+namespace MemoryAllocator::OS
+{
+    size_t get_page_size();
+
+    void *alloc_pages(size_t pages_count);
+
+    bool append_pages(void *addr_after_last_page_in_chain, size_t pages_count);
+
+    void free_pages(void *start, size_t pages_count);
+}

os/CMakeLists.txt

+if (${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
+    set(
+            ITMO_OS_SOURCES
+            ./windows.cpp
+    )
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
+    message(STATUS "Fuck linux")
+    set(
+            ITMO_OS_SOURCES
+            ./linux.cpp
+    )
+else ()
+    message(FATAL_ERROR "Fuck ${CMAKE_SYSTEM_NAME}")
+endif ()
+
+
+add_library(itmo_OS OBJECT ${ITMO_OS_SOURCES})
+target_include_directories(itmo_OS PUBLIC ./include)
+
+add_executable(itmo_OS_test test.cpp)
+target_link_libraries(itmo_OS_test PRIVATE itmo_OS)
\ No newline at end of file

os/linux.cpp

+#include <cstddef>
+#include <cstdint>
+
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include <itmo/mem.hpp>
+
+size_t MemoryAllocator::OS::get_page_size()
+{
+    return (size_t) (getpagesize());
+}
+
+void *MemoryAllocator::OS::alloc_pages(size_t pages_count)
+{
+    return mmap(nullptr, pages_count * getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+}
+
+bool MemoryAllocator::OS::append_pages(void *addr_after_last_page_in_chain, size_t pages_count)
+{
+    void *actual_start = mmap((void *) addr_after_last_page_in_chain, pages_count * getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (actual_start != addr_after_last_page_in_chain)
+    {
+        munmap((void *) actual_start, pages_count * getpagesize());
+        return true;
+    }
+    return false;
+}
+
+void MemoryAllocator::OS::free_pages(void *start, size_t pages_count)
+{
+    munmap((void *) start, pages_count * getpagesize());
+}
\ No newline at end of file

os/test.cpp

+#include <cstddef>
+#include <cstdint>
+
+#include <itmo/mem.hpp>
+
+
+static void *mp(void *ptr, size_t pages_count) {
+    return (void *)(((uintptr_t)ptr) + MemoryAllocator::OS::get_page_size() * pages_count);
+}
+
+int main(int argc, char **argv)
+{
+    void *p = MemoryAllocator::OS::alloc_pages(1);
+    if (p == nullptr)
+        return 1;
+
+    MemoryAllocator::OS::free_pages(p, 1);
+    p = MemoryAllocator::OS::alloc_pages(3);
+    if (p == nullptr)
+        return 1;
+    MemoryAllocator::OS::free_pages(mp(p, 1), 1);
+    if (MemoryAllocator::OS::append_pages(mp(p, 1), 1))
+    {
+        return 1;
+    }
+    MemoryAllocator::OS::free_pages(mp(p, 1), 1);
+    if (!MemoryAllocator::OS::append_pages(mp(p, 1), 2))
+    {
+        return 1;
+    }
+    MemoryAllocator::OS::free_pages(p, 1);
+    MemoryAllocator::OS::free_pages(mp(p, 2), 1);
+
+    return 0;
+}
\ No newline at end of file

[Andrey Zhdanov]

Формально выполнено не то задание, но принято