6 files changed, 199 insertions, 4 deletions
diff --git a/works/life/operating-system-experiment/CMakeLists.txt b/works/life/operating-system-experiment/CMakeLists.txt
index 540574b..806ec74 100644
--- a/works/life/operating-system-experiment/CMakeLists.txt
+++ b/works/life/operating-system-experiment/CMakeLists.txt
@@ -9,13 +9,15 @@ set(CMAKE_CXX_STANDARD 17)
 
 find_package(fmt CONFIG REQUIRED)
 find_package(Microsoft.GSL CONFIG REQUIRED)
-add_library(cru_system SHARED Thread.cpp)
+add_library(cru_system SHARED Thread.cpp Mutex.cpp)
 target_link_libraries(cru_system PUBLIC Microsoft.GSL::GSL fmt::fmt)
 target_compile_definitions(cru_system PUBLIC CRU_EXPORT_API)
 if(UNIX)
 target_link_libraries(cru_system PUBLIC pthread)
 endif()
 
-
 add_executable(main main.cpp)
-target_link_libraries(main PRIVATE cru_system)
-\ No newline at end of file
+target_link_libraries(main PRIVATE cru_system)
+
+add_executable(data_race_demo DataRaceDemo.cpp)
+target_link_libraries(data_race_demo PRIVATE cru_system)
diff --git a/works/life/operating-system-experiment/DataRaceDemo.cpp b/works/life/operating-system-experiment/DataRaceDemo.cpp
new file mode 100644
index 0000000..9589eb3
--- /dev/null
+++ b/works/life/operating-system-experiment/DataRaceDemo.cpp
@@ -0,0 +1,27 @@
+#include "Thread.h"
+
+#include <iostream>
+
+int main() {
+  unsigned data = 0;
+
+  cru::Thread t1([&data] {
+    for (int i = 0; i < 100000; i++)
+      data += 10;
+  });
+
+  cru::Thread t2([&data] {
+    for (int i = 0; i < 100000; i++)
+      data += 10;
+  });
+
+  std::cout << "Created thread: " << t1.GetNativeID() << '\n';
+  std::cout << "Created thread: " << t2.GetNativeID() << '\n';
+
+  t1.Join();
+  t2.Join();
+  std::cout << "Answer is " << data << ", which is "
+            << (data == 200000 ? "correct" : "false") << '\n';
+
+  return 0;
+}
diff --git a/works/life/operating-system-experiment/Mutex.cpp b/works/life/operating-system-experiment/Mutex.cpp
new file mode 100644
index 0000000..6a91885
--- /dev/null
+++ b/works/life/operating-system-experiment/Mutex.cpp
@@ -0,0 +1,78 @@
+#include "Mutex.h"
+
+#include <cassert>
+#include <pthread.h>
+
+#ifndef CRU_WINDOWS
+#include <errno.h>
+#endif
+
+namespace cru {
+Mutex::Mutex() {
+#ifdef CRU_WINDOWS
+#else
+  mutex_ = std::make_unique<pthread_mutex_t>();
+
+  auto c = pthread_mutex_init(mutex_.get(), nullptr);
+  assert(c == 0);
+#endif
+}
+
+Mutex::Mutex(Mutex &&other)
+#ifdef CRU_WINDOWS
+#else
+    : mutex_(std::move(other.mutex_))
+#endif
+{
+}
+
+Mutex &Mutex::operator=(Mutex &&other) {
+  if (this != &other) {
+    Destroy();
+    mutex_ = std::move(other.mutex_);
+  }
+  return *this;
+}
+
+Mutex::~Mutex() { Destroy(); }
+
+void Mutex::Lock() {
+#ifdef CRU_WINDOWS
+#else
+  assert(mutex_);
+  auto c = pthread_mutex_lock(mutex_.get());
+  assert(c == 0);
+#endif
+}
+
+bool Mutex::TryLock() {
+#ifdef CRU_WINDOWS
+#else
+  assert(mutex_);
+  auto c = pthread_mutex_trylock(mutex_.get());
+  assert(c == 0 || c == EBUSY);
+  return c == 0 ? true : false;
+#endif
+}
+
+void Mutex::Unlock() {
+#ifdef CRU_WINDOWS
+#else
+  assert(mutex_);
+  auto c = pthread_mutex_unlock(mutex_.get());
+  assert(c == 0);
+#endif
+}
+
+void Mutex::Destroy() {
+#ifdef CRU_WINDOWS
+#else
+  if (mutex_ != nullptr) {
+    auto c = pthread_mutex_destroy(mutex_.get());
+    assert(c);
+    mutex_ = nullptr;
+  }
+#endif
+}
+
+} // namespace cru
diff --git a/works/life/operating-system-experiment/Mutex.h b/works/life/operating-system-experiment/Mutex.h
new file mode 100644
index 0000000..163d9ca
--- /dev/null
+++ b/works/life/operating-system-experiment/Mutex.h
@@ -0,0 +1,44 @@
+#ifndef HEADER_MUTEX_H
+#define HEADER_MUTEX_H
+
+#include "Base.h"
+
+#include <memory>
+
+#ifdef CRU_WINDOWS
+#include <Windows.h>
+#else
+#include <pthread.h>
+#endif
+
+namespace cru {
+class CRU_API Mutex {
+public:
+  Mutex();
+
+  Mutex(const Mutex &other) = delete;
+  Mutex &operator=(const Mutex &other) = delete;
+
+  Mutex(Mutex &&other);
+  Mutex &operator=(Mutex &&other);
+
+  ~Mutex();
+
+public:
+  void Lock();
+  bool TryLock();
+
+  void Unlock();
+
+private:
+  void Destroy();
+
+private:
+#ifdef CRU_WINDOWS
+#else
+  std::unique_ptr<pthread_mutex_t> mutex_;
+#endif
+};
+} // namespace cru
+
+#endif
+\ No newline at end of file
diff --git a/works/life/operating-system-experiment/Thread.cpp b/works/life/operating-system-experiment/Thread.cpp
index 9d9f5dd..7e3c784 100644
--- a/works/life/operating-system-experiment/Thread.cpp
+++ b/works/life/operating-system-experiment/Thread.cpp
@@ -59,6 +59,36 @@ void Thread::Detach() {
   detached_ = true;
 }
 
+#ifdef CRU_WINDOWS
+DWORD
+#else
+pthread_t
+#endif
+Thread::GetNativeID() {
+#ifdef CRU_WINDOWS
+  assert(thread_handle_);
+  return thread_id_;
+#else
+  assert(thread_);
+  return *thread_;
+#endif
+}
+
+#ifdef CRU_WINDOWS
+HANDLE
+#else
+pthread_t
+#endif
+Thread::GetNativeHandle() {
+#ifdef CRU_WINDOWS
+  assert(thread_handle_);
+  return thread_handle_;
+#else
+  assert(thread_);
+  return *thread_;
+#endif
+}
+
 void Thread::swap(Thread &other) noexcept {
 #ifdef CRU_WINDOWS
   Thread temp = std::move(*this);
@@ -81,6 +111,7 @@ void Thread::Destroy() noexcept {
     detached_ = false;
     joined_ = false;
 #ifdef CRU_WINDOWS
+    thread_id_ = 0;
     thread_handle_ = nullptr;
 #else
     thread_ = nullptr;
diff --git a/works/life/operating-system-experiment/Thread.h b/works/life/operating-system-experiment/Thread.h
index 69a402c..56fdcb0 100644
--- a/works/life/operating-system-experiment/Thread.h
+++ b/works/life/operating-system-experiment/Thread.h
@@ -18,7 +18,6 @@
 #include <type_traits>
 #include <utility>
 #include <vector>
-#include <tuple>
 
 namespace cru {
 class CRU_API Thread {
@@ -35,6 +34,20 @@ public:
   void Join();
   void Detach();
 
+#ifdef CRU_WINDOWS
+  DWORD
+#else
+  pthread_t
+#endif
+  GetNativeID();
+
+#ifdef CRU_WINDOWS
+  HANDLE
+#else
+  pthread_t
+#endif
+  GetNativeHandle();
+
   void swap(Thread &other) noexcept;
 
 private: