[DTrace-devel] [PATCH 1/5] build: overridable configuration variables
Kris Van Hees
kris.van.hees at oracle.com
Thu Dec 21 19:08:23 UTC 2023
On Wed, Nov 29, 2023 at 04:08:25PM +0000, Nick Alcock wrote:
> The Makeconfig checks are purely compile-time, so should always work: but if
> they don't, it is sometimes desirable to be able to override them.
>
> This change causes every check-* invocation in Makeconfig to respond to
> HAVE_* make variables set on the command line, and also to produce a line in
> 'make help' of the general form
>
> HAVE_LIBSYSTEMD=[yes/no] Override check for presence of sd_notify in libsystemd
The way you automated this results in rather odd help output because the
automated help output of course fails to capture the nuances of the tests they
represent.
E.g. HAVE_LIBFUSE3 is about whether fuse2 or fuse3 is used, but it is reported
as:
Override check for presence of fuse_session_receive_buf in libfuse3
Likewise, HAVE_SYSTEMD and HAVE_LIBCTF are about existance of libraries even
though the test is based on a specific symbol.
But HAVE_FUSE_LOG etc *are* about specific functions, but then HAVE_CLOSE_RANGE
specifies specific arguments in the help output? That is bound to have someone
wonder why that one has specific arguments and the others don't? Is the test
about that function accepting those specific arguments or something else?
I think sometimes automation is not our friend. It might be better to just
write a help line for each override that clearly explains what it means.
> etc.
>
> (The escaping in make-override-help to figure out how many tabs to insert to
> properly align the help will make your eyes bleed. One $ for every nested
> $(eval $(call ...)): thank goodness they're all at the same level!)
>
> Signed-off-by: Nick Alcock <nick.alcock at oracle.com>
> ---
> Makeconfig | 101 +++++++++++++++++++++++++++++++++++++++-------------
> Makeoptions | 13 ++++---
> 2 files changed, 83 insertions(+), 31 deletions(-)
>
> diff --git a/Makeconfig b/Makeconfig
> index 08cb48101f9a..f6a28d8f79f5 100644
> --- a/Makeconfig
> +++ b/Makeconfig
> @@ -10,6 +10,23 @@
> CONFIG_H = $(objdir)/config.h
> CONFIG_MK = $(objdir)/config.mk
>
> +# Emit a help rule for an override.
> +#
> +# Syntax: $(call make-overrride-help,var,help-string)
> +define make-override-help
> +help::
> + width=$$$$(printf '$(1)=[yes/no]' | wc -c); \
> + tabs=""; \
> + if [[ $$$${width} -gt 31 ]]; then \
> + tabs=' '; \
> + elif [[ $$$${width} -gt 23 ]]; then \
> + tabs='\t'; \
> + elif [[ $$$${width} -gt 15 ]]; then \
> + tabs='\t\t'; \
> + fi; \
> + printf "$(1)=[yes/no]$$$${tabs}Override check for$(2)\n" >&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.
> @@ -20,14 +37,24 @@ CONFIG_MK = $(objdir)/config.mk
> # Syntax: $(call check-header-rule,name,function,header)
> define check-header-rule
> $(objdir)/.config/config.$(1).h $(objdir)/.config/config.$(1).mk: $(objdir)/.config/.dir.stamp
> - if printf '#include <%s.h>\nint main(void) { %s; }' "$(3)" "$(2)" | \
> - $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -D_GNU_SOURCE -Werror=implicit-function-declaration -c -o /dev/null -x c - >/dev/null 2>&1; then \
> - echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> - echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> - else \
> - echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> - echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> - fi
> + case x$(HAVE_$(1)) in \
> + xyes) echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk;; \
> + xno) echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk;; \
> + *) if printf '#include <%s.h>\nint main(void) { %s; }' "$(3)" "$(2)" | \
> + $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -D_GNU_SOURCE -Werror=implicit-function-declaration -c -o /dev/null -x c - >/dev/null 2>&1; then \
> + echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> + else \
> + echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> + fi;; \
> + *) echo "HAVE_$(1) must be yes or no, not $(HAVE_$(1))" >&2; \
> + false;; \
> + esac
> +
> +$(eval $(call make-override-help,HAVE_$(1), presence of $(2) in $(3).h))
>
> $(CONFIG_H): $(objdir)/.config/config.$(1).h
> $(CONFIG_MK): $(objdir)/.config/config.$(1).mk
> @@ -43,14 +70,24 @@ endef
> # Syntax: $(call check-symbol,name,symbol,library)
> define check-symbol-rule
> $(objdir)/.config/config.$(1).h $(objdir)/.config/config.$(1).mk: $(objdir)/.config/.dir.stamp
> - if echo 'void $(2)(); int main(void) { $(2)(); }' | \
> - $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -o /dev/null -x c - -l$(3) >/dev/null 2>&1; then \
> - echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> - echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> - else \
> - echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> - echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> - fi
> + case x$(HAVE_$(1)) in \
> + xyes) echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk;; \
> + xno) echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk;; \
> + x) if echo 'void $(2)(); int main(void) { $(2)(); }' | \
> + $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -o /dev/null -x c - -l$(3) >/dev/null 2>&1; then \
> + echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> + else \
> + echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> + fi;; \
> + *) echo "HAVE_$(1) must be yes or no, not $(HAVE_$(1))" >&2; \
> + false;; \
> + esac
> +
> +$(eval $(call make-override-help,HAVE_$(1), presence of $(2) in lib$(3)))
>
> $(CONFIG_H): $(objdir)/.config/config.$(1).h
> $(CONFIG_MK): $(objdir)/.config/config.$(1).mk
> @@ -66,14 +103,24 @@ endef
> # Syntax: $(call check-header-symbol-rule,name,symbol,library,header)
> define check-header-symbol-rule
> $(objdir)/.config/config.$(1).h $(objdir)/.config/config.$(1).mk: $(objdir)/.config/.dir.stamp
> - if printf '#include <%s.h>\nint main(void) { %s; }' "$(4)" "$(2)" | \
> - $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -D_GNU_SOURCE -Werror=implicit-function-declaration -o /dev/null -x c - -l$(3) >/dev/null 2>&1; then \
> - echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> - echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> - else \
> - echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> - echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> - fi
> + case x$(HAVE_$(1)) in \
> + xyes) echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk;; \
> + xno) echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk;; \
> + *) if printf '#include <%s.h>\nint main(void) { %s; }' "$(4)" "$(2)" | \
> + $(CC) $(filter-out --coverage,$(CFLAGS) $(LDFLAGS)) -D_GNU_SOURCE -Werror=implicit-function-declaration -o /dev/null -x c - -l$(3) >/dev/null 2>&1; then \
> + echo '#define HAVE_$(1) 1' > $(objdir)/.config/config.$(1).h; \
> + echo 'HAVE_$(1)=y' > $(objdir)/.config/config.$(1).mk; \
> + else \
> + echo '/* #undef HAVE_$(1) */' > $(objdir)/.config/config.$(1).h; \
> + echo '# HAVE_$(1) undefined' > $(objdir)/.config/config.$(1).mk; \
> + fi;; \
> + *) echo "HAVE_$(1) must be yes or no, not $(HAVE_$(1))" >&2; \
> + false;; \
> + esac
> +
> +$(eval $(call make-override-help,HAVE_$(1), presence of $(2) in lib$(3) and $(4).h))
>
> $(CONFIG_H): $(objdir)/.config/config.$(1).h
> $(CONFIG_MK): $(objdir)/.config/config.$(1).mk
> @@ -92,6 +139,9 @@ $(CONFIG_MK):
> echo 'CONFIGURED := yes' >> $(objdir)/config.mk
> cat $(objdir)/.config/*.mk >> $(objdir)/config.mk 2>/dev/null || true
>
> +help::
> + 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,STRRSTR,strrstr,c))
> @@ -103,3 +153,6 @@ 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))
> $(eval $(call check-header-rule,GETTID,gettid,unistd))
> +
> +help::
> + printf "\n" >&2
> diff --git a/Makeoptions b/Makeoptions
> index cec68a0af2bc..25234092c6dd 100644
> --- a/Makeoptions
> +++ b/Makeoptions
> @@ -1,7 +1,7 @@
> # The implementation of the configurable make options.
> #
> # Oracle Linux DTrace.
> -# Copyright (c) 2011, 2022, Oracle and/or its affiliates. All rights reserved.
> +# Copyright (c) 2011, 2023, Oracle and/or its affiliates. All rights reserved.
> # Licensed under the Universal Permissive License v 1.0 as shown at
> # http://oss.oracle.com/licenses/upl.
>
> @@ -13,13 +13,12 @@ libfuse2 ?= no
>
> help::
> @printf "Options:\n\n" >&2
> - @printf "make debugging=yes [targets] Disable optimization to make debugger use easier\n" >&2
> - @printf "make coverage=yes [targets] Turn on coverage support in the testsuite\n" >&2
> - @printf "make verbose=yes [target] Enable verbose building\n" >&2
> - @printf "make dof_dbg=yes [targets] Turn on especially noisy DOF parser debugging\n\n" >&2
> + @printf "make debugging=yes [targets]\tDisable optimization to make debugger use easier\n" >&2
> + @printf "make coverage=yes [targets]\tTurn on coverage support in the testsuite\n" >&2
> + @printf "make verbose=yes [target]\tEnable verbose building\n" >&2
> + @printf "make dof_dbg=yes [targets]\tTurn on especially noisy DOF parser debugging\n\n" >&2
> @printf "Dependencies:\n\n" >&2
> - @printf "make libfuse2=yes [targets] Build against libfuse 2 even if libfuse 3 is found\n" >&2
> - @printf "\n" >&2
> + @printf "make libfuse2=yes [targets]\tBuild against libfuse 2 even if libfuse 3 is found\n\n" >&2
>
> ifneq ($(debugging),no)
> override CFLAGS += -O0 -g
> --
> 2.42.0.271.g85384428f1
>
>
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