[Bug] CMake with FHS tries to create a directory outside build on configure

[HuidaeCho]

cmake .. -DWITH_FHS=ON tries to create /usr/local/libexec/grass/gui/wxpython on configuring before make install:

grass/CMakeLists.txt

Line 191 in 8bf4f68

file(MAKE_DIRECTORY "${GISBASE}/gui/wxpython")

GISBASE is set here (CMAKE_INSTALL_PREFIX=/usr/local for UNIX [1]):

grass/cmake/modules/GRASSInstallDirs.cmake

Lines 81 to 82 in 8bf4f68

	set(GISBASE ${CMAKE_INSTALL_PREFIX}/${GISBASE_DIR})
	set(RUNTIME_GISBASE "${OUTDIR}/${GISBASE_DIR}")

RUNTIME_GISBASE (not clear why it's called "runtime") is created in the build output directory, which is fine. I think we should create any directories or files outside the build directory only on installation.

[nilason]

Glad to see you reached so far as to test FHS! :-) I haven't, since I left over the baton a year ago.

There are a number of hard coded links (relative to GISBASE) to files/directories in code, which I didn't want to address at that time.

It may look like:

grass/lib/gis/color_rules.c

Line 364 in 18e0846

snprintf(path, GPATH_MAX, "%s/etc/colors.desc", G_gisbase());

The whole block you refer to was a temporary hack to "get thing moving" at the time:

grass/CMakeLists.txt

Lines 175 to 194 in 18e0846

	# TODO: a proper fix to this workaround
	if(WITH_FHS)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_DEMODIR}
	${RUNTIME_GISBASE}/demolocation SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_FONTSDIR} ${RUNTIME_GISBASE}/fonts
	SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_ETCDIR}/colors
	${RUNTIME_GISBASE}/etc/colors SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_ETCDIR}/colors.desc
	${RUNTIME_GISBASE}/etc/colors.desc SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_ETCDIR}/element_list
	${RUNTIME_GISBASE}/etc/element_list SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_ETCDIR}/renamed_options
	${RUNTIME_GISBASE}/etc/renamed_options SYMBOLIC)
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_ETCDIR}/VERSIONNUMBER
	${RUNTIME_GISBASE}/etc/VERSIONNUMBER SYMBOLIC)
	file(MAKE_DIRECTORY "${GISBASE}/gui/wxpython")
	file(CREATE_LINK ${OUTDIR}/${GRASS_INSTALL_GUIDIR}/wxpython/xml
	${RUNTIME_GISBASE}/gui/wxpython/xml SYMBOLIC)
	endif()

The files/directories are with FHS located elsewhere, and this we need to address in code. They are $GISBASE +

• demolocation
• fonts
• etc/colors
• etc/color.desc
• etc/element_list
• etc/renamed_option
• etc/VERSIONNUMBER
• gui/wxpython/xml

I'm now sure how to best address this to account for both current system and the FHS, but the time has come for us to find a solution.

(RUNTIME_GISBASE refers to the GISBASE in the build stage, which is needed because grass is running in parts of the building process, generating docs etc, but also to facilitate the possibility to test without installing. The choice of prefixing with "RUNTIME" is not carved in stone and may be reconsidered.)

[nilason]

I'm now sure how to best address this to account for both current system and the FHS, but the time has come for us to find a solution.

Perhaps we can introduce another environment variable: e.g., GRASS_SHARE_DIR, which under FHS is /usr/share/grass and under current system equals (for these elements) GISBASE (see #3661 (comment))

• demolocation may be found under $GRASS_SHARE_DIR/demolocation
• etc/element_list under $GRASS_SHARE_DIR/etc/element_list
  ... etc.

Which in practice could look like:

 snprintf(path, GPATH_MAX, "%s/etc/colors.desc", G_grass_share_dir()); 

gui/wxpython/xml will need another approach, depending on how we deal with Python code.