cpp: thread: support for std::thread and std::this_thread

This commit adds support for std::thread and std::this_thread
when the configured C++ standard is >= C++11.

The implementation uses POSIX threads under the hood.

Signed-off-by: Christopher Friedt <[email protected]>

Author: cfriedt

lib/cpp/CMakeLists.txt

@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: Apache-2.0
 
 add_subdirectory(abi)
-
+add_subdirectory(std)
 add_subdirectory_ifdef(CONFIG_MINIMAL_LIBCPP minimal)

lib/cpp/Kconfig

@@ -143,6 +143,14 @@ config CPP_RTTI
 
 endif # !MINIMAL_LIBCPP
 
+config CPP_STD_THREAD
+	bool "Support for std::thread"
+	default y if !STD_CPP98
+	depends on !STD_CPP98
+	select POSIX_API
+	help
+	  This option enables support for std::thread and std::this_thread.
+
 config CPP_STATIC_INIT_GNU
 	bool
 	select STATIC_INIT_GNU

lib/cpp/std/CMakeLists.txt

@@ -0,0 +1,3 @@
+zephyr_sources_ifdef(CONFIG_CPP_STD_THREAD
+  thread.cpp
+)

lib/cpp/std/thread.cpp

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2020 Friedt Professional Engineering Services, Inc
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define _GLIBCXX_VISIBILITY(x)
+#define _GLIBCXX_THREAD_ABI_COMPAT 1
+
+#include <threads.h>
+
+#include <thread>
+
+#include <zephyr/init.h>
+#include <zephyr/kernel.h>
+
+static void __z_cpp_thread_terminate() FUNC_NORETURN;
+static void __z_cpp_thread_terminate()
+{
+	thrd_exit(0);
+}
+
+static int __z_cpp_thread_init(void)
+{
+	/* use thrd_exit(0) instead of std::abort() to avoid kernel panic */
+	std::set_terminate(__z_cpp_thread_terminate);
+	return 0;
+}
+SYS_INIT(__z_cpp_thread_init, PRE_KERNEL_1, 0);