zephyr: Add Zephyr module support code under contrib/zephyr/

This is Zephyr module glue code.  We've decided contrib/ to store
architecture or OS specific code.

Zephyr still doesn't support many drivers and interfaces, yet.

For UDP interface, we check HAVE_SYS_SOCKET_H to enable it or not but
the current check_include_files() doesn't work with Zephyr build
system.  Thus, explicitly disabled in contrib/zephyr/CMakeLists.txt.

Note that turning HAVE_SYS_SOCKET_H ON doesn't build if_udp.  you need
to enable CONFIG_POSIX_API=y add tell libcsp about the include
directory for POSIX subsystem.

      target_include_directories(libcsp PRIVATE
   +    $<TARGET_PROPERTY:posix_subsys,INTERFACE_INCLUDE_DIRECTORIES>
        $<TARGET_PROPERTY:zephyr_interface,INTERFACE_INCLUDE_DIRECTORIES>
        )

Signed-off-by: Yasushi SHOJI <[email protected]>

Author: yashi

contrib/zephyr/CMakeLists.txt

@@ -0,0 +1,34 @@
+if(CONFIG_LIBCSP)
+  set(CMAKE_SYSTEM_NAME "Zephyr")
+  set(CMAKE_BUILD_TYPE None)
+  set(CMAKE_C_COMPILE_FEATURES c_std_11)
+
+  # check_include_file() doesn't work in Zephyr module
+  # https://github.com/zephyrproject-rtos/zephyr/issues/31193
+  # predefine it
+  set(HAVE_SYS_SOCKET_H OFF)
+
+  add_subdirectory(../.. build)
+
+  # Zephyr compiler options
+  target_include_directories(libcsp PRIVATE
+    $<TARGET_PROPERTY:zephyr_interface,INTERFACE_INCLUDE_DIRECTORIES>
+    )
+
+  target_include_directories(libcsp SYSTEM PRIVATE
+    $<TARGET_PROPERTY:zephyr_interface,INTERFACE_SYSTEM_INCLUDE_DIRECTORIES>
+    )
+
+  target_compile_definitions(libcsp PRIVATE
+    $<TARGET_PROPERTY:zephyr_interface,INTERFACE_COMPILE_DEFINITIONS>
+    )
+
+  target_compile_options(libcsp PRIVATE
+    $<TARGET_PROPERTY:zephyr_interface,INTERFACE_COMPILE_OPTIONS>
+    -fno-builtin -Wno-shadow -Wno-cast-align
+    )
+
+  add_dependencies(libcsp ${SYSCALL_LIST_H_TARGET})
+  zephyr_append_cmake_library(libcsp)
+  target_link_libraries(libcsp PUBLIC zephyr_interface)
+endif()

contrib/zephyr/Kconfig

@@ -0,0 +1,23 @@
+# libcsp Cubesat Space Protocol
+
+# Copyright (c) 2021 Space Cubics, LLC.
+# SPDX-License-Identifier: Apache-2.0
+
+config LIBCSP
+	bool "Enable Cubesat Space Protocol Support"
+	select POSIX_CLOCK
+	help
+	  This option enables the Cubesat Space Protocol (CSP) library.
+
+config LIBCSP_DEBUG
+	bool "Enable CSP debugging option"
+	help
+	  This option enables CSP debugging options.
+
+if LIBCSP_DEBUG
+
+module = LIBCSP
+module-str = libcsp
+source "subsys/logging/Kconfig.template.log_config"
+
+endif # LIBCSP_DEBUG

contrib/zephyr/module.yml

@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) 2021 Space Cubics, LLC.
+
+build:
+  cmake: zephyr
+  kconfig: zephyr/Kconfig