OOT module don't see #include <img_mgmt/image.h>

[CreativeIndustryAg]

Hello

I have to prepare own DFU protocol, so I implement it in project directory and it works.
But when I move this functionality to OOT module, then compilation return error:

            fatal error: img_mgmt/image.h: No such file or directory
               11 | #include <img_mgmt/image.h>_

The code (except moving it to OOT module) is the same and the problem is only with this file, rest are findable.
It seems somehow CMake can't see it or I don't know.

Could you help me?

[yashi]

That's because mcumgr sets include directories for the app, and app only.

zephyr/subsys/mgmt/mcumgr/CMakeLists.txt

Line 9 in 07c6af3

zephyr_interface_library_named(mgmt_mcumgr)

zephyr/cmake/modules/extensions.cmake

Lines 590 to 618 in 07c6af3

	# 1.2.1 zephyr_interface_library_*
	#
	# A Zephyr interface library is a thin wrapper over a CMake INTERFACE
	# library. The most important responsibility of this abstraction is to
	# ensure that when a user KConfig-enables a library then the header
	# files of this library will be accessible to the 'app' library.
	#
	# This is done because when a user uses Kconfig to enable a library he
	# expects to be able to include its header files and call its
	# functions out-of-the box.
	#
	# A Zephyr interface library should be used when there exists some
	# build information (include directories, defines, compiler flags,
	# etc.) that should be applied to a set of Zephyr libraries and 'app'
	# might be one of these libraries.
	#
	# Zephyr libraries must explicitly call
	# zephyr_library_link_libraries(<interface_library>) to use this build
	# information. 'app' is treated as a special case for usability
	# reasons; a Kconfig option (CONFIG_APP_LINK_WITH_<interface_library>)
	# should exist for each interface_library and will determine if 'app'
	# links with the interface_library.
	#
	# This API has a constructor like the zephyr_library API has, but it
	# does not have wrappers over the other cmake target functions.
	macro(zephyr_interface_library_named name)
	add_library(${name} INTERFACE)
	set_property(GLOBAL APPEND PROPERTY ZEPHYR_INTERFACE_LIBS ${name})
	endmacro()

[CreativeIndustryAg]

@yashi You are the MEN :)

Many thanks.
Do you think is this possible to use this macro inside OOT module?

[yashi]

Sure can. But that doesn't allow your module to find mgmt include directory.

I haven't tested but if you are creating a library as an out-of-tree module, you need to do something like:

# Let the app know where to find your include directory
# This is only for the include dirs.
zephyr_interface_library_named(yourlib)
target_include_directories(yourlib INTERFACE ${ZEPHYR_CURRENT_MODULE_DIR}/include)

# Now create the library itself.
zephyr_library()

# add your library source files to your library crated implictly by zephyr_library()
zephyr_library_sources(mylib.c)

# Your library need include directories from mgmt
zephyr_library_link_libraries(mgmt_mcumgr)

Search zephyr_interface_library_named under out of tree modules to see real world examples.

Hope it helps.

[CreativeIndustryAg]

@yashi Thanks a lot, I will test it after noon.

Best wishes