[DTrace-devel] [PATCH v3 7/9] build: support make help-overrides-option and help-overrides-header

[Kris Van Hees]

On Fri, Jan 26, 2024 at 01:58:47PM +0000, Nick Alcock wrote:
> Add a make help-overrides-option which reports certain configuration
> variables (those relating to external libraries) in a different format, as
> if they were configure options.
> 
> HAVE_FOO_BAR is printed as
> 
> --have-foo-bar	...
> 
> This is used by the configure script to provide two formats for such options
> (expected to be more necessary when they are needed at all, due to the lack
> of useful automatic replacements for such libraries), via ENV_OVERRIDES or
> --configure-options=.
> 
> We split the header emitted at the top of make help-overrides off into make
> help-overrides-header because the configure script will want to emit the
> header before the help-overrides-option output (which is printed first).
> 
> Signed-off-by: Nick Alcock <nick.alcock at oracle.com>

Reviewed-by: Kris Van Hees <kris.van.hees at oracle.com>

> ---
>  Makeconfig | 38 ++++++++++++++++++++++++++++++++------
>  1 file changed, 32 insertions(+), 6 deletions(-)
> 
> diff --git a/Makeconfig b/Makeconfig
> index 1e031ada9801..cd3a91096cb3 100644
> --- a/Makeconfig
> +++ b/Makeconfig
> @@ -30,6 +30,23 @@ help-overrides::
>  	       "$$$$(printf "%s" "$(2)" | sed 's,(.*),,g')" >&2
>  endef
>  
> +# Emit a help rule for an override's config option.
> +#
> +# Syntax: $(call make-overrride-option-help,var,help-string)
> +define make-override-option-help
> +help-overrides-option::
> +	width=$$$$(printf -- '--with-$(1)=[yes/no]' | wc -c); \
> +	tabs=""; \
> +	if [[ $$$${width} -gt 31 ]]; then \
> +	    tabs=' '; \
> +	elif [[ $$$${width} -gt 23 ]]; then \
> +	    tabs='\t'; \
> +	elif [[ $$$${width} -gt 15 ]]; then \
> +	    tabs='\t\t'; \
> +	fi; \
> +	printf -- "--with-%s=[yes/no]$$$${tabs}Override check for$(2)\n" "$$$$(printf -- '$(1)' | LC_COLLATE=C tr '[A-Z_]' '[a-z-]')" >&2
> +endef
> +
>  # Generate a makefile rule to check for the presence of FUNCTION
>  # in HEADER and emit an appropriate header file fragment into a
>  # file under $(objdir)/.config.
> @@ -73,7 +90,14 @@ endef
>  # The first argument must be suitable for a filename fragment,
>  # for a makefile rule name and for a #define.
>  #
> -# Syntax: $(call check-symbol,name,symbol,library)
> +# Also emit a rule to print help for this override to standard
> +# error, and (if OPTION) is set, a rule to print help for
> +# this override in standard configure --with-* form.  (This is
> +# used for options relating to things for which we do not have
> +# compatibility fallbacks, for which configure-style --with-*
> +# options seem particularly desirable.)
> +#
> +# Syntax: $(call check-symbol-rule,name,symbol,library,option)
>  define check-symbol-rule
>  $(objdir)/.config/config.$(1).h $(objdir)/.config/config.$(1).mk: $(objdir)/.config/.dir.stamp
>  	val="$(HAVE_$(1))"; \
> @@ -97,6 +121,8 @@ $(objdir)/.config/config.$(1).h $(objdir)/.config/config.$(1).mk: $(objdir)/.con
>  	rm -f $(CONFIG_MK)
>  
>  $(eval $(call make-override-help,HAVE_$(1), presence of $(2) in lib$(3)))
> +$(if $(4),
> +  $(eval $(call make-override-option-help,$(1), presence of $(2) in $(3).h)),)
>  
>  $(CONFIG_H): $(objdir)/.config/config.$(1).h
>  $(CONFIG_MK): $(objdir)/.config/config.$(1).mk
> @@ -152,16 +178,16 @@ $(CONFIG_MK):
>  	echo 'CONFIGURED := yes' >> $(objdir)/config.mk
>  	cat $(objdir)/.config/*.mk >> $(objdir)/config.mk 2>/dev/null || true
>  
> -help-overrides::
> +help-overrides-header::
>  	printf "Overrides for library and symbol searches:\n\n" >&2
>  
>  $(eval $(call check-symbol-rule,ELF_GETSHDRSTRNDX,elf_getshdrstrndx,elf))
> -$(eval $(call check-symbol-rule,LIBCTF,ctf_open,ctf))
> +$(eval $(call check-symbol-rule,LIBCTF,ctf_open,ctf,t))
>  $(eval $(call check-symbol-rule,STRRSTR,strrstr,c))
> -$(eval $(call check-symbol-rule,LIBSYSTEMD,sd_notify,systemd))
> +$(eval $(call check-symbol-rule,LIBSYSTEMD,sd_notify,systemd,t))
>  ifndef WANTS_LIBFUSE2
>  $(eval $(call check-symbol-rule,FUSE_LOG,fuse_set_log_func,fuse3))
> -$(eval $(call check-symbol-rule,LIBFUSE3,fuse_session_receive_buf,fuse3))
> +$(eval $(call check-symbol-rule,LIBFUSE3,fuse_session_receive_buf,fuse3,t))
>  endif
>  $(eval $(call check-header-rule,FUSE_NUMA,fuse_set_numa,fuse/fuse_lowlevel))
>  $(eval $(call check-header-symbol-rule,CLOSE_RANGE,close_range(3,~0U,0),c,unistd))
> @@ -170,4 +196,4 @@ $(eval $(call check-header-rule,GETTID,gettid,unistd))
>  help-overrides::
>  	printf "\n" >&2
>  
> -help:: help-overrides
> +help:: help-overrides-header help-overrides
> -- 
> 2.43.0.272.gce700b77fd
> 
>