libs: begin extraction of kernel std

3 files changed, 100 insertions, 0 deletions

diff --git a/libs/kstd/CMakeLists.txt b/libs/kstd/CMakeLists.txt
new file mode 100644
index 0000000..06083f3
--- /dev/null
+++ b/libs/kstd/CMakeLists.txt
@@ -0,0 +1,24 @@
+cmake_minimum_required(VERSION "3.27")
+
+project("kstd"
+    LANGUAGES CXX
+    VERSION "1.0.0"
+)
+
+add_library("kstd" STATIC)
+add_library("libs::kstd" ALIAS "kstd")
+
+target_sources("kstd" PRIVATE
+    "src/mutex.cpp"
+)
+
+target_sources("kstd" PUBLIC
+    FILE_SET HEADERS
+    BASE_DIRS "include"
+    FILES
+    "include/kstd/mutex.hpp"
+)
+
+target_include_directories("kstd" PUBLIC
+    "include"
+)
diff --git a/libs/kstd/include/kstd/mutex.hpp b/libs/kstd/include/kstd/mutex.hpp
new file mode 100644
index 0000000..cf8549f
--- /dev/null
+++ b/libs/kstd/include/kstd/mutex.hpp
@@ -0,0 +1,60 @@
+#ifndef KSTD_MUTEX_HPP
+#define KSTD_MUTEX_HPP
+
+#include <atomic>
+
+namespace kstd
+{
+  /**
+   * @brief Custom mutex implementation, that simply wraps an atomic boolean to keep track if the mutex is already in
+   * use by another thread or not.
+   */
+  struct mutex
+  {
+    /**
+     * @brief Defaulted constructor.
+     */
+    mutex() = default;
+
+    /**
+     * @brief Defaulted destructor.
+     */
+    ~mutex() = default;
+
+    /**
+     * @brief Deleted copy constructor.
+     */
+    mutex(const mutex &) = delete;
+
+    /**
+     * @brief Deleted assignment operator.
+     */
+    mutex & operator=(const mutex &) = delete;
+
+    /**
+     * @brief Lock the mutex (blocks for as long as it is not available).
+     */
+    [[gnu::section(".stl_text")]]
+    auto lock() -> void;
+
+    /**
+     * @brief Try to lock the mutex (non-blocking).
+     *
+     * @return True if lock has been acquired and false otherwise.
+     */
+    [[gnu::section(".stl_text")]]
+    auto try_lock() -> bool;
+
+    /**
+     * @brief Unlock the mutex.
+     */
+    [[gnu::section(".stl_text")]]
+    auto unlock() -> void;
+
+  private:
+    std::atomic<bool> locked = {false};  // Atomic boolean to track if mutex is locked or not.
+  };
+
+}  // namespace kstd
+
+#endif
\ No newline at end of file
diff --git a/libs/kstd/src/mutex.cpp b/libs/kstd/src/mutex.cpp
new file mode 100644
index 0000000..cfb1c84
--- /dev/null
+++ b/libs/kstd/src/mutex.cpp
@@ -0,0 +1,16 @@
+#include "kstd/mutex.hpp"
+
+namespace kstd
+{
+  auto mutex::lock() -> void
+  {
+    while (!try_lock())
+    {
+      asm volatile("nop");
+    }
+  }
+
+  auto mutex::try_lock() -> bool { return !locked.exchange(true, std::memory_order_acquire); }
+
+  auto mutex::unlock() -> void { locked.store(false, std::memory_order_release); }
+}  // namespace kstd