libs/kstd/src/mutex.cpp


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#include "kstd/mutex"

#include "kstd/os/error.hpp"

#include <atomic>

namespace kstd
{

  [[gnu::section(".stl_text")]]
  mutex::mutex() = default;

  [[gnu::section(".stl_text")]]
  mutex::~mutex()
  {
    if (m_locked.test(std::memory_order_relaxed))
    {
      os::panic("[KSTD] Tried to destroy a locked mutex.");
    }
  }

  [[gnu::section(".stl_text")]]
  auto mutex::lock() -> void
  {
    while (!try_lock())
    {
      asm volatile("nop");
    }
  }

  [[gnu::section(".stl_text")]]
  auto mutex::try_lock() -> bool
  {
    return !m_locked.test_and_set(std::memory_order_acquire);
  }

  [[gnu::section(".stl_text")]]
  auto mutex::unlock() -> void
  {
    m_locked.clear(std::memory_order_release);
  }

}  // namespace kstd