Makefile, README: Break installation into a target for each mandir

Instead of having a monolithic 'make install', break it into
multiple targets such as 'make install-man3'.  This simplifies
packaging, for example in Debian, where they break this project
into several packages: 'manpages' and 'manpages-dev', each
containing different mandirs.

The above allows for multithread installation: 'make -j'

Also, don't overwrite files that don't need to be overwritten, by
having a target for files, which makes use of make's timestamp
comparison.

This allows for much faster installation times.

For comparison, on my laptop (i7-8850H; 6C/12T):

Old Makefile:
	~/src/linux/man-pages$ time sudo make >/dev/null

	real	0m7.509s
	user	0m5.269s
	sys	0m2.614s

	The times with the old makefile, varied a lot, between
	5 and 10 seconds.  The times after applying this patch
	are much more consistent.  BTW, I compared these times to
	the very old Makefile of man-pages-5-09, and those were
	around 3.5 s, so it was a bit of my fault to have such a
	slow Makefile, when I changed the Makefile some weeks ago.

New Makefile (full clean install):
	~/src/linux/man-pages$ time sudo make >/dev/null

	real	0m5.160s
	user	0m4.326s
	sys	0m1.137s
	~/src/linux/man-pages$ time sudo make -j2 >/dev/null

	real	0m1.602s
	user	0m2.529s
	sys	0m0.289s
	~/src/linux/man-pages$ time sudo make -j >/dev/null

	real	0m1.398s
	user	0m2.502s
	sys	0m0.281s

	Here we can see that 'make -j' drops times drastically,
	compared to the old monolithic Makefile.  Not only that,
	but since when we are working with the man pages there
	aren't many pages involved, times will be even better.

	Here are some times with a single page changed (touched):

New Makefile (one page touched):
	~/src/linux/man-pages$ touch man2/membarrier.2
	~/src/linux/man-pages$ time sudo make install
	-	INSTALL	/usr/local/share/man/man2/membarrier.2

	real	0m0.988s
	user	0m0.966s
	sys	0m0.025s
	~/src/linux/man-pages$ touch man2/membarrier.2
	~/src/linux/man-pages$ time sudo make install -j
	-	INSTALL	/usr/local/share/man/man2/membarrier.2

	real	0m0.989s
	user	0m0.943s
	sys	0m0.049s

Also, modify the output of the make install and uninstall commands
so that a line is output for each file or directory that is
installed, similarly to the kernel's Makefile.  This doesn't apply
to html targets, which haven't been changed in this commit.

Also, make sure that for each invocation of $(INSTALL_DIR), no
parents are created, (i.e., avoid `mkdir -p` behavior).  The GNU
make manual states that it can create race conditions.  Instead,
declare as a prerequisite for each directory its parent directory,
and let make resolve the order of creation.

Also, use ':=' instead of '=' to improve performance, by
evaluating each assignment only once.

Ensure than the shell is not called when not needed, by removing
all ";" and quotes in the commands.

See also: <https://stackoverflow.com/q/67862417/6872717>

Specify conventions and rationales used in the Makefile in a comment.

Add copyright.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Alejandro Colomar 2021-06-09 19:01:08 +02:00 committed by Michael Kerrisk
parent 14987c153f
commit 336ae0d258
2 changed files with 215 additions and 44 deletions

251
Makefile
View File

@ -1,26 +1,210 @@
# Do not print "Entering directory ..."
########################################################################
# Copyright (C) 2021 Alejandro Colomar <alx.manpages@gmail.com>
# SPDX-License-Identifier: GPL-2.0 OR LGPL-2.0
########################################################################
# Conventions:
#
# - Follow "Makefile Conventions" from the "GNU Coding Standards" closely.
# However, when something could be improved, don't follow those.
# - Uppercase variables, when referring files, refer to files in this repo.
# - Lowercase variables, when referring files, refer to system files.
# - Variables starting with '_' refer to absolute paths, including $(DESTDIR).
# - Variables ending with '_' refer to a subdir of their parent dir, which
# is in a variable of the same name but without the '_'. The subdir is
# named after this project: <*/man>.
# - Variables ending in '_rm' refer to files that can be removed (exist).
# - Variables ending in '_rmdir' refer to dirs that can be removed (exist).
# - Targets of the form '%-rm' remove their corresponding file '%'.
# - Targets of the form '%/.-rmdir' remove their corresponding dir '%/'.
# - Targets of the form '%/.' create their corresponding directory '%/'.
# - Every file or directory to be created depends on its parent directory.
# This avoids race conditions caused by `mkdir -p`. Only the root
# directories are created with parents.
# - The 'FORCE' target is used to make phony some variables that can't be
# .PHONY to avoid some optimizations.
#
########################################################################
MAKEFLAGS += --no-print-directory
MAKEFLAGS += --silent
MAKEFLAGS += --warn-undefined-variables
htmlbuilddir = $(CURDIR)/.html
HTOPTS =
DESTDIR =
prefix = /usr/local
datarootdir = $(prefix)/share
docdir = $(datarootdir)/doc
mandir = $(datarootdir)/man
htmldir = $(docdir)
htmldir_ = $(htmldir)/man
htmlext = .html
htmlbuilddir := $(CURDIR)/.html
HTOPTS :=
DESTDIR :=
prefix := /usr/local
datarootdir := $(prefix)/share
docdir := $(datarootdir)/doc
MANDIR := $(CURDIR)
mandir := $(datarootdir)/man
MAN1DIR := $(MANDIR)/man1
MAN2DIR := $(MANDIR)/man2
MAN3DIR := $(MANDIR)/man3
MAN4DIR := $(MANDIR)/man4
MAN5DIR := $(MANDIR)/man5
MAN6DIR := $(MANDIR)/man6
MAN7DIR := $(MANDIR)/man7
MAN8DIR := $(MANDIR)/man8
man1dir := $(mandir)/man1
man2dir := $(mandir)/man2
man3dir := $(mandir)/man3
man4dir := $(mandir)/man4
man5dir := $(mandir)/man5
man6dir := $(mandir)/man6
man7dir := $(mandir)/man7
man8dir := $(mandir)/man8
manext := \.[0-9]
man1ext := .1
man2ext := .2
man3ext := .3
man4ext := .4
man5ext := .5
man6ext := .6
man7ext := .7
man8ext := .8
htmldir := $(docdir)
htmldir_ := $(htmldir)/man
htmlext := .html
INSTALL := install
INSTALL_DATA := $(INSTALL) -m 644
INSTALL_DIR := $(INSTALL) -m 755 -d
RM := rm
RMDIR := rmdir --ignore-fail-on-non-empty
MAN_SECTIONS := 1 2 3 4 5 6 7 8
INSTALL = install
INSTALL_DATA = $(INSTALL) -m 644
INSTALL_DIR = $(INSTALL) -m 755 -d
.PHONY: all
all:
$(MAKE) uninstall;
$(MAKE) install;
$(MAKE) uninstall
$(MAKE) install
%/.:
$(info - INSTALL $(@D))
$(INSTALL_DIR) $(@D)
%-rm:
$(info - RM $*)
$(RM) $*
%-rmdir:
$(info - RMDIR $(@D))
$(RMDIR) $(@D)
.PHONY: install
install: install-man | installdirs
@:
.PHONY: installdirs
installdirs: | installdirs-man
@:
.PHONY: uninstall remove
uninstall remove: uninstall-man
@:
.PHONY: clean
clean:
find man?/ -type f \
|while read f; do \
rm -f "$(htmlbuilddir)/$$f".*; \
done;
########################################################################
# man
MANPAGES := $(sort $(shell find $(MANDIR)/man?/ -type f | grep '$(manext)$$'))
_manpages := $(patsubst $(MANDIR)/%,$(DESTDIR)$(mandir)/%,$(MANPAGES))
_man1pages := $(filter %$(man1ext),$(_manpages))
_man2pages := $(filter %$(man2ext),$(_manpages))
_man3pages := $(filter %$(man3ext),$(_manpages))
_man4pages := $(filter %$(man4ext),$(_manpages))
_man5pages := $(filter %$(man5ext),$(_manpages))
_man6pages := $(filter %$(man6ext),$(_manpages))
_man7pages := $(filter %$(man7ext),$(_manpages))
_man8pages := $(filter %$(man8ext),$(_manpages))
MANDIRS := $(sort $(shell find $(MANDIR)/man? -type d))
_mandirs := $(patsubst $(MANDIR)/%,$(DESTDIR)$(mandir)/%/.,$(MANDIRS))
_man1dir := $(filter %man1/.,$(_mandirs))
_man2dir := $(filter %man2/.,$(_mandirs))
_man3dir := $(filter %man3/.,$(_mandirs))
_man4dir := $(filter %man4/.,$(_mandirs))
_man5dir := $(filter %man5/.,$(_mandirs))
_man6dir := $(filter %man6/.,$(_mandirs))
_man7dir := $(filter %man7/.,$(_mandirs))
_man8dir := $(filter %man8/.,$(_mandirs))
_mandir := $(DESTDIR)$(mandir)/.
_manpages_rm := $(addsuffix -rm,$(wildcard $(_manpages)))
_man1pages_rm := $(filter %$(man1ext)-rm,$(_manpages_rm))
_man2pages_rm := $(filter %$(man2ext)-rm,$(_manpages_rm))
_man3pages_rm := $(filter %$(man3ext)-rm,$(_manpages_rm))
_man4pages_rm := $(filter %$(man4ext)-rm,$(_manpages_rm))
_man5pages_rm := $(filter %$(man5ext)-rm,$(_manpages_rm))
_man6pages_rm := $(filter %$(man6ext)-rm,$(_manpages_rm))
_man7pages_rm := $(filter %$(man7ext)-rm,$(_manpages_rm))
_man8pages_rm := $(filter %$(man8ext)-rm,$(_manpages_rm))
_mandirs_rmdir := $(addsuffix -rmdir,$(wildcard $(_mandirs)))
_man1dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man1dir)))
_man2dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man2dir)))
_man3dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man3dir)))
_man4dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man4dir)))
_man5dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man5dir)))
_man6dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man6dir)))
_man7dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man7dir)))
_man8dir_rmdir := $(addsuffix -rmdir,$(wildcard $(_man8dir)))
_mandir_rmdir := $(addsuffix -rmdir,$(wildcard $(_mandir)))
install_manX := $(foreach x,$(MAN_SECTIONS),install-man$(x))
installdirs_manX := $(foreach x,$(MAN_SECTIONS),installdirs-man$(x))
uninstall_manX := $(foreach x,$(MAN_SECTIONS),uninstall-man$(x))
.SECONDEXPANSION:
$(_manpages): $(DESTDIR)$(mandir)/man%: $(MANDIR)/man% | $$(@D)/.
$(info - INSTALL $@)
$(INSTALL_DATA) -T $< $@
$(_mandirs): %/.: | $$(dir %). $(_mandir)
$(_mandirs_rmdir): $(DESTDIR)$(mandir)/man%/.-rmdir: $$(_man%pages_rm) FORCE
$(_mandir_rmdir): $(uninstall_manX) FORCE
.PHONY: $(install_manX)
$(install_manX): install-man%: $$(_man%pages) | installdirs-man%
@:
.PHONY: install-man
install-man: $(install_manX)
@:
.PHONY: $(installdirs_manX)
$(installdirs_manX): installdirs-man%: $$(_man%dir) $(_mandir)
@:
.PHONY: installdirs-man
installdirs-man: $(installdirs_manX)
@:
.PHONY: $(uninstall_manX)
$(uninstall_manX): uninstall-man%: $$(_man%pages_rm) $$(_man%dir_rmdir)
@:
.PHONY: uninstall-man
uninstall-man: $(_mandir_rmdir) $(uninstall_manX)
@:
########################################################################
# html
# Use with
# make HTOPTS=whatever html
@ -57,28 +241,6 @@ installdirs-html:
$(INSTALL_DIR) "$(DESTDIR)$(htmldir_)/$$d" || exit $$?; \
done;
.PHONY: install
install: | installdirs
find man?/ -type f \
|while read f; do \
$(INSTALL_DATA) -T "$$f" "$(DESTDIR)$(mandir)/$$f" || exit $$?; \
done;
.PHONY: installdirs
installdirs:
find man?/ -type d \
|while read d; do \
$(INSTALL_DIR) "$(DESTDIR)$(mandir)/$$d" || exit $$?; \
done;
.PHONY: uninstall remove
uninstall remove:
find man?/ -type f \
|while read f; do \
rm -f "$(DESTDIR)$(mandir)/$$f" || exit $$?; \
rm -f "$(DESTDIR)$(mandir)/$$f".* || exit $$?; \
done;
.PHONY: uninstall-html
uninstall-html:
find man?/ -type f \
@ -86,12 +248,9 @@ uninstall-html:
rm -f "$(DESTDIR)$(htmldir_)/$$f".* || exit $$?; \
done;
.PHONY: clean
clean:
find man?/ -type f \
|while read f; do \
rm -f "$(htmlbuilddir)/$$f".* || exit $$?; \
done;
########################################################################
# tests
# Check if groff reports warnings (may be words of sentences not displayed)
# from https://lintian.debian.org/tags/groff-message.html
@ -109,3 +268,7 @@ check-groff-warnings:
# someone might also want to look at /var/catman/cat2 or so ...
# a problem is that the location of cat pages varies a lot
########################################################################
FORCE:

8
README
View File

@ -26,9 +26,17 @@ To install to a path different from /usr/local, use
distribution from its destination. Use with caution, and remember to
use "prefix" if desired, as with the "install" target.
To install only a specific man section (mandir) such as man3, use
"make install-man3". Similar syntax can be used to uninstall a
specific man section, such as man7: "make uninstall-man7".
"make" or "make all" will perform "make uninstall" followed by "make
install".
Consider using multiple threads (at least 2) when installing
these man pages, as the Makefile is optimized for multiple threads:
"make -j install".
Copyrights
==========
See the 'man-pages-x.y.Announce' file.