Add Chromium-only Blender WebEngine parity work

blender-5.2.0/intern/cycles/util/thread.h

@@ -0,0 +1,73 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: Apache-2.0 */
+
+#pragma once
+
+#include <condition_variable>
+#include <functional>
+#include <mutex>
+
+#if defined(__APPLE__) || defined(__linux__) && !defined(__GLIBC__)
+#  include <pthread.h>
+#else
+#  include <thread>
+#endif
+
+#ifdef _WIN32
+#  include "util/windows.h"
+#endif
+
+/* NOTE: Use tbb/spin_mutex.h instead of util_tbb.h because some of the TBB
+ * functionality requires RTTI, which is disabled for OSL kernel. */
+#include <tbb/spin_mutex.h>
+
+CCL_NAMESPACE_BEGIN
+
+using thread_mutex = std::mutex;
+using thread_scoped_lock = std::unique_lock<std::mutex>;
+using thread_condition_variable = std::condition_variable;
+
+/**
+ * Own thread implementation similar to std::thread, so we can set a
+ * custom stack size on macOS.
+ */
+class thread {
+ public:
+  thread(std::function<void()> run_cb);
+  ~thread();
+
+  static void *run(void *arg);
+  bool join();
+
+ protected:
+  std::function<void()> run_cb_;
+#if defined(__APPLE__) || defined(__linux__) && !defined(__GLIBC__)
+  pthread_t pthread_id;
+#else
+  std::thread std_thread;
+#endif
+  bool joined_;
+};
+
+using thread_spin_lock = tbb::spin_mutex;
+
+class thread_scoped_spin_lock {
+ public:
+  explicit thread_scoped_spin_lock(thread_spin_lock &lock) : lock_(lock)
+  {
+    lock_.lock();
+  }
+
+  ~thread_scoped_spin_lock()
+  {
+    lock_.unlock();
+  }
+
+  /* TODO(sergey): Implement manual control over lock/unlock. */
+
+ protected:
+  thread_spin_lock &lock_;
+};
+
+CCL_NAMESPACE_END