diff options
Diffstat (limited to 'build-aux')
-rw-r--r-- | build-aux/Makefile.README.txt | 164 | ||||
-rw-r--r-- | build-aux/Makefile.each.head/.gitignore | 0 | ||||
-rw-r--r-- | build-aux/Makefile.each.tail/.gitignore | 0 | ||||
-rw-r--r-- | build-aux/Makefile.each.tail/10-std.mk | 46 | ||||
-rw-r--r-- | build-aux/Makefile.head.mk | 63 | ||||
-rw-r--r-- | build-aux/Makefile.once.head/.gitignore | 0 | ||||
-rw-r--r-- | build-aux/Makefile.once.head/00-gnuconf.mk | 149 | ||||
-rw-r--r-- | build-aux/Makefile.once.head/00-write-ifchanged.mk | 1 | ||||
-rw-r--r-- | build-aux/Makefile.once.head/10-std.mk | 39 | ||||
-rw-r--r-- | build-aux/Makefile.once.tail/.gitignore | 0 | ||||
-rw-r--r-- | build-aux/Makefile.tail.mk | 51 | ||||
-rwxr-xr-x | build-aux/write-ifchanged | 25 |
12 files changed, 538 insertions, 0 deletions
diff --git a/build-aux/Makefile.README.txt b/build-aux/Makefile.README.txt new file mode 100644 index 0000000..e06ba52 --- /dev/null +++ b/build-aux/Makefile.README.txt @@ -0,0 +1,164 @@ +Luke's AutoMake +=============== + +Yo, this document is incomplete. It describes the magical +automake.{head,tail}.mk Makefiles and how to use them, kinda. + +I wrote a "clone" of automake. I say clone, because it works +differently. Yeah, I need a new name for it. + +High-level overview +------------------- + +Now, what this does for you is: + +It makes it _easy_ to write non-recursive Makefiles--and ones that are +similar to plain recursive Makefiles, at that! (search for the paper +"Recursive Make Considered Harmful") As harmful as recursive make is, +it's historically been difficult to to write non-recursive Makefiles. +This makes it easy. + +It also makes it easy to follow the GNU standards for your makefiles: +it takes care of this entire table of .PHONY targets for you: + +| this | and this | are aliases for this | +|------+------------------+--------------------------------------------------------| +| all | build | $(outdir)/build | +| | install | $(outdir)/install | +| | uninstall | $(outdir)/uninstall | +| | mostlyclean | $(outdir)/mostlyclean | +| | clean | $(outdir)/clean | +| | distclean | $(outdir)/distclean | +| | maintainer-clean | $(outdir)/maintainer-clean | +| | check | $(outdir)/check (not implemented for you) | +| | dist | $(topoutdir)/$(PACKAGE)-$(VERSION).tar.gz (not .PHONY) | + +(You are still responsible for implementing the `$(outdir)/check` +target in each of your Makefiles.) + +What you have to do is: + +In each source directory, you write a `Makefile`, very similarly to if +you were writing for plain GNU Make, with + + topoutdir ?= ... + topsrcdir ?= ... + include $(topsrcdir)/build-aux/Makefile.head.mk + + # your makefile + + include $(topsrcdir)/build-aux/Makefile.tail.mk + +And in the top-level source directory, Write your own helper makefiles +that get included: + - `common.once.head.mk`: before parsing any of your Makefiles + - `common.each.head.mk`: before parsing each of your Makefiles + - `common.each.tail.mk`: after parsing each of your Makefiles + - `common.each.tail.mk`: after parsing all of your Makefiles + +The `common.*.mk` makefiles are nice for including generic pattern +rules and variables that aren't specific to a directory. + +You're probably thinking that this sounds too good to be true! +Unfortunately, there are two major deviations from writing a plain +recursive Makefile: + + 1. all targets and prerequisites (including .PHONY targets!) need to + be prefixed with + `$(srcdir)`/`$(outdir)`/`$(topsrcdir)`/`$(topoutdir)`. + * sub-gotcha: this means that if a pattern rule has a + prerequisite that may be in srcdir or outdir, then it must be + specified twice, once for each case. + 2. if a prerequisite is in a directory "owned" by another Makefile, + you must filter the pathname through `am_path`: + `$(call am_path,YOUR_PATH)`. Further, that path must NOT contain + a `..` segment; if you need to refer to a sibling directory, do it + relative to `$(topoutdir)` or `$(topsrcdir)`. + +Telling automake about your program +----------------------------------- + +You tell automake what to do for you by setting some variables. They +are all prefixed with `am_`; this prefix may be changed by editing the +`_am` variable at the top of `automake.head.mk`. + +The exception to this is the `am_path` variable, which is a macro that +is used to make a list of filenames relative to the appropriate +directory, because unlike normal GNU (Auto)Make, `$(outdir)` isn't +nescessarily equal to `.`. See above. + +There are several commands that generate files; simply record the list +of files that each command generates as the following variable +variables: + +| Variable | Create Command | Delete Command | Description | Relative to | +|--------------+----------------+-----------------------------+-----------------------------------+-------------| +| am_src_files | emacs | rm -rf . | Files that the developer writes | srcdir | +| am_gen_files | ??? | make maintainer-clean | Files the developer compiles | srcdir | +| am_cfg_files | ./configure | make distclean | Users' compile-time configuration | outdir | +| am_out_files | make all | make mostlyclean/make clean | Files the user compiles | outdir | +| am_sys_files | make install | make uninstall | Files the user installs | DESTDIR | + +In addition, there are two more variables that control not how files +are created, but how they are deleted: + +| Variable | Affected command | Description | Relative to | +|----------------+------------------+------------------------------------------------+-------------| +| am_clean_files | make clean | A list of things to `rm` in addition to the | outdir | +| | | files in `$(am_out_files)`. (Example: `*.o`) | | +|----------------+------------------+------------------------------------------------+-------------| +| am_slow_files | make mostlyclean | A list of things that (as an exception) should | outdir | +| | | _not_ be deleted. (otherwise, `mostlyclean` | | +| | | is the same as `clean`) | | + +Finally, there are two variables that express the relationships +between directories: + +| Variable | Description | +|------------+---------------------------------------------------------| +| am_subdirs | A list of other directories (containing Makefiles) that | +| | may be considered "children" of this | +| | directory/Makefile; building a phony target in this | +| | directory should also build it in the subdirectory. | +| | They are not necesarily actually subdirectories of this | +| | directory in the filesystem. | +|------------+---------------------------------------------------------| +| am_depdirs | A list of other directories (containing Makefiles) that | +| | contain or generate files that are dependencies of | +| | targets in this directory. They are not necesarily | +| | actually subdirectories of this directory in the | +| | filesystem. Except for files that are dependencies of | +| | files in this directory, things in the dependency | +| | directory will not be built. | + +Tips, notes +----------- + +I like to have the first (non-comment) line in a Makefile be: + + include $(dir $(lastword $(MAKEFILE_LIST)))/../../config.mk + +(adjusting the number of `../` sequences as nescessary). Then, my +(user-editable) `config.mk` is of the form: + + ifeq ($(topsrcdir),) + topoutdir := $(patsubst %/,%,$(dir $(lastword $(MAKEFILE_LIST)))) + topsrcdir := $(topoutdir) + + # your configuration + + endif + +If the package has a `./configure` script, then I have it modifiy +topsrcdir as necessary, as well as modifying whatever other parts of +the configuration. All of the configuration lives in `config.mk`; +`./configure` doesn't modify any `Makefile`s, it just generates +`config.mk`, and copies (or (sym?)link?) every `$(srcdir)/Makefile` to +`$(outdir)/Makefile`. + +---- +Copyright (C) 2016 Luke Shumaker + +This documentation file is placed into the public domain. If that is +not possible in your legal system, I grant you permission to use it in +absolutely every way that I can legally grant to you. diff --git a/build-aux/Makefile.each.head/.gitignore b/build-aux/Makefile.each.head/.gitignore new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/build-aux/Makefile.each.head/.gitignore diff --git a/build-aux/Makefile.each.tail/.gitignore b/build-aux/Makefile.each.tail/.gitignore new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/build-aux/Makefile.each.tail/.gitignore diff --git a/build-aux/Makefile.each.tail/10-std.mk b/build-aux/Makefile.each.tail/10-std.mk new file mode 100644 index 0000000..5150a71 --- /dev/null +++ b/build-aux/Makefile.each.tail/10-std.mk @@ -0,0 +1,46 @@ +# Copyright (C) 2015-2016 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +# Add some more defaults to the *_files variables +std.clean_files += $(std.gen_files) $(std.cfg_files) $(std.out_files) + +# Fix each variable at its current value to avoid any weirdness +$(foreach c,src gen cfg out sys clean slow,$(eval std.$c_files := $$(std.$c_files))) + +# Make each of the standard variables relative to the correct directory +std.src_files := $(patsubst ./%,%,$(addprefix $(srcdir)/,$(std.src_files))) +std.gen_files := $(patsubst ./%,%,$(addprefix $(srcdir)/,$(std.gen_files))) +std.cfg_files := $(patsubst ./%,%,$(addprefix $(outdir)/,$(std.cfg_files))) +std.out_files := $(patsubst ./%,%,$(addprefix $(outdir)/,$(std.out_files))) +std.sys_files := $(addprefix $(DESTDIR),$(std.sys_files)) +std.clean_files := $(patsubst ./%,%,$(addprefix $(outdir)/,$(std.clean_files))) +std.slow_files := $(patsubst ./%,%,$(addprefix $(outdir)/,$(std.slow_files))) + +# Creative targets +$(outdir)/build : $(std.out_files) +$(outdir)/install : $(std.sys_files) +$(outdir)/installdirs: $(sort $(dir $(std.sys_files))) + +# Destructive targets +_std.uninstall/$(outdir) := $(std.sys_files) +_std.mostlyclean/$(outdir) := $(filter-out $(std.slow_files) $(std.cfg_files) $(std.gen_files) $(std.src_files),$(std.clean_files)) +_std.clean/$(outdir) := $(filter-out $(std.cfg_files) $(std.gen_files) $(std.src_files),$(std.clean_files)) +_std.distclean/$(outdir) := $(filter-out $(std.gen_files) $(std.src_files),$(std.clean_files)) +_std.maintainer-clean/$(outdir) := $(filter-out $(std.src_files),$(std.clean_files)) +$(addprefix $(outdir)/,uninstall mostlyclean clean distclean maintainer-clean): %: %-hook + $(RM) -- $(sort $(filter-out %/,$(_std.$(@F)/$(@D)))) + $(RM) -r -- $(sort $(filter %/,$(_std.$(@F)/$(@D)))) + $(RMDIR_P) $(sort $(dir $(_std.$(@F)/$(@D)))) 2>/dev/null || $(TRUE) +$(foreach t,uninstall mostlyclean clean distclean maintainer-clean, $(outdir)/$t-hook):: +.PHONY: $(foreach t,uninstall mostlyclean clean distclean maintainer-clean, $(outdir)/$t-hook) diff --git a/build-aux/Makefile.head.mk b/build-aux/Makefile.head.mk new file mode 100644 index 0000000..63a3462 --- /dev/null +++ b/build-aux/Makefile.head.mk @@ -0,0 +1,63 @@ +# Copyright (C) 2015-2016 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# This bit only gets evaluated once, at the very beginning +ifeq ($(_at.NO_ONCE),) + +ifeq ($(topsrcdir),) +$(error topsrcdir must be set before including Makefile.head.mk) +endif +ifeq ($(topoutdir),) +$(error topoutdir must be set before including Makefile.head.mk) +endif + +_at.noslash = $(patsubst %/.,%,$(patsubst %/,%,$1)) +# These are all $(call _at.func,parent,child) +#at.relto = $(if $2,$(shell realpath -sm --relative-to='$1' $2)) +_at.is_subdir = $(filter $(abspath $1)/%,$(abspath $2)/.) +_at.relto_helper = $(if $(call _at.is_subdir,$1,$2),$(patsubst $1/%,%,$(addsuffix /.,$2)),$(addprefix ../,$(call _at.relto_helper,$(patsubst %/,%,$(dir $1)),$2))) +_at.relto = $(call _at.noslash,$(call _at.relto_helper,$(call _at.noslash,$(abspath $1)),$(call _at.noslash,$(abspath $2)))) +at.relto = $(foreach p,$2,$(call _at.relto,$1,$p)) +# Note that _at.is_subdir says that a directory is a subdirectory of +# itself. +at.path = $(call at.relto,.,$1) + +define at.nl + + +endef + +_at.rest = $(wordlist 2,$(words $1),$1) +_at.reverse = $(if $1,$(call _at.reverse,$(_at.rest))) $(firstword $1) + +at.dirlocal += at.subdirs +at.dirlocal += at.depdirs + +include $(sort $(wildcard $(topsrcdir)/build-aux/Makefile.once.head/*.mk)) + +endif # _at.NO_ONCE + +# This bit gets evaluated for each Makefile + +## Set outdir and srcdir (assumes that topoutdir and topsrcdir are +## already set) +outdir := $(call at.path,$(dir $(lastword $(filter-out %.mk,$(MAKEFILE_LIST))))) +srcdir := $(call at.path,$(topsrcdir)/$(call _at.relto,$(topoutdir),$(outdir))) + +_at.included_makefiles := $(_at.included_makefiles) $(call at.path,$(outdir)/Makefile) + +$(foreach v,$(at.dirlocal),$(eval $v=)) + +include $(sort $(wildcard $(topsrcdir)/build-aux/Makefile.each.head/*.mk)) diff --git a/build-aux/Makefile.once.head/.gitignore b/build-aux/Makefile.once.head/.gitignore new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/build-aux/Makefile.once.head/.gitignore diff --git a/build-aux/Makefile.once.head/00-gnuconf.mk b/build-aux/Makefile.once.head/00-gnuconf.mk new file mode 100644 index 0000000..79ecc34 --- /dev/null +++ b/build-aux/Makefile.once.head/00-gnuconf.mk @@ -0,0 +1,149 @@ +# Copyright (C) 2016 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# This file is based on ยง7.2 "Makefile Conventions" of the release of +# the GNU Coding Standards dated April 13, 2016. + +gnuconf.pkgname ?= $(PACKAGE) +ifeq ($(gnuconf.pkgname),) +$(error gnuconf.pkgname must be set) +endif + +# 7.2.2: Utilities in Makefiles +# ----------------------------- + +# It's ok to hard-code these commands in rules, but who wants to +# memorize the list of what's ok? +AWK ?= awk +CAT ?= cat +CMP ?= cmp +CP ?= cp +DIFF ?= diff +ECHO ?= echo +EGREP ?= egrep +EXPR ?= expr +FALSE ?= false +GREP ?= grep +INSTALL_INFO ?= install-info +LN ?= ln +LS ?= ls +MKDIR ?= mkdir +MV ?= mv +PRINTF ?= printf +PWD ?= pwd +RM ?= rm +RMDIR ?= rmdir +SED ?= sed +SLEEP ?= sleep +SORT ?= sort +TAR ?= tar +TEST ?= test +TOUCH ?= touch +TR ?= tr +TRUE ?= true + +# These must be user-configurable +AR ?= ar +ARFLAGS ?= +BISON ?= bison +BISONFLAGS ?= +CC ?= cc +CCFLAGS ?= $(CFLAGS) +FLEX ?= flex +FLEXFLAGS ?= +INSTALL ?= install +INSTALLFLAGS ?= +LD ?= ld +LDFLAGS ?= +LDCONFIG ?= ldconfig #TODO +LDCONFIGFLAGS ?= +LEX ?= lex +LEXFLAGS ?= $(LFLAGS) +#MAKE +MAKEINFO ?= makeinfo +MAKEINFOFLAGS ?= +RANLIB ?= ranlib #TODO +RANLIBFLAGS ?= +TEXI2DVI ?= texi2dvi +TEXI2DVIFLAGS ?= +YACC ?= yacc +YACCFLAGS ?= $(YFLAGS) + +CFLAGS ?= +LFLAGS ?= +YFLAGS ?= + +LN_S ?= ln -s #TODO + +CHGRP ?= chgrp +CHMOD ?= chmod +CHOWN ?= chown +MKNOD ?= mknod + +# 7.2.3 Variables for Specifying Commands +# --------------------------------------- + +INSTALL_PROGRAM ?= $(INSTALL) +INSTALL_DATA ?= ${INSTALL} -m 644 + +# 7.2.5 Variables for Installation Directories +# -------------------------------------------- + +# Root for the installation +prefix ?= /usr/local +exec_prefix ?= $(prefix) +# Executable programs +bindir ?= $(exec_prefix)/bin +sbindir ?= $(exec_prefix)/sbin +libexecdir ?= $(exec_prefix)/libexec +# Data files +datarootdir ?= $(prefix)/share +datadir ?= $(datarootdir) +sysconfdir ?= $(prefix)/etc +sharedstatedir ?= $(prefix)/com +localstatedir ?= $(prefix)/var +runstatedir ?= $(localstatedir)/run +# Specific types of files +includedir ?= $(prefix)/include +oldincludedir ?= /usr/include +docdir ?= $(datarootdir)/doc/$(gnuconf.pkgname) +infodir ?= $(datarootdir)/info +htmldir ?= $(docdir) +dvidir ?= $(docdir) +pdfdir ?= $(docdir) +psdir ?= $(docdir) +libdir ?= $(exec_prefix)/lib +lispdir ?= $(datarootdir)/emacs/site-lisp +localedir ?= $(datarootdir)/locale + +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 + +manext ?= .1 +man1ext ?= .1 +man2ext ?= .2 +man3ext ?= .3 +man4ext ?= .4 +man5ext ?= .5 +man6ext ?= .6 +man7ext ?= .7 +man8ext ?= .8 diff --git a/build-aux/Makefile.once.head/00-write-ifchanged.mk b/build-aux/Makefile.once.head/00-write-ifchanged.mk new file mode 100644 index 0000000..79ef1c4 --- /dev/null +++ b/build-aux/Makefile.once.head/00-write-ifchanged.mk @@ -0,0 +1 @@ +WRITE_IFCHANGED = $(topsrcdir)/build-aux/write-ifchanged diff --git a/build-aux/Makefile.once.head/10-std.mk b/build-aux/Makefile.once.head/10-std.mk new file mode 100644 index 0000000..3e058ec --- /dev/null +++ b/build-aux/Makefile.once.head/10-std.mk @@ -0,0 +1,39 @@ +# Copyright (C) 2015-2016 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Declare the default target +all: build +.PHONY: all noop + +# Standard creative PHONY targets +at.phony += build install installdirs +# Standard destructive PHONY targets +at.phony += uninstall mostlyclean clean distclean maintainer-clean + +at.dirlocal += std.src_files +at.dirlocal += std.gen_files +at.dirlocal += std.cfg_files +at.dirlocal += std.out_files +at.dirlocal += std.sys_files +at.dirlocal += std.clean_files +at.dirlocal += std.slow_files + +# User configuration + +DESTDIR ?= + +RM ?= rm -f +RMDIR_P ?= rmdir -p +TRUE ?= true diff --git a/build-aux/Makefile.once.tail/.gitignore b/build-aux/Makefile.once.tail/.gitignore new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/build-aux/Makefile.once.tail/.gitignore diff --git a/build-aux/Makefile.tail.mk b/build-aux/Makefile.tail.mk new file mode 100644 index 0000000..dfbad5a --- /dev/null +++ b/build-aux/Makefile.tail.mk @@ -0,0 +1,51 @@ +# Copyright (C) 2015-2016 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# This bit gets evaluated for each Makefile processed + +include $(call _at.reverse,$(sort $(wildcard $(topsrcdir)/build-aux/Makefile.each.tail/*.mk))) + +at.subdirs := $(patsubst ./%,%,$(addprefix $(outdir)/,$(at.subdirs))) +at.depdirs := $(patsubst ./%,%,$(addprefix $(outdir)/,$(at.depdirs))) + +# Move all of the dirlocal variables to their namespaced version +$(foreach v,$(at.dirlocal),$(eval $v/$(outdir) := $$($v))) +$(foreach v,$(at.dirlocal),$(eval undefine $v)) + +# Remember that this is a directory that we've visited +_at.outdirs := $(_at.outdirs) $(outdir) + +# Generic phony target declarations: +# mark them phony +.PHONY: $(addprefix $(outdir)/,$(at.phony)) +# have them depend on subdirs +$(foreach t,$(at.phony),$(eval $(outdir)/$t: $(addsuffix /$t,$(at.subdirs/$(outdir))))) + +# Include Makefiles from other directories +$(foreach _at.NO_ONCE,y,\ + $(foreach makefile,$(call at.path,$(addsuffix /Makefile,$(at.subdirs/$(outdir)) $(at.depdirs/$(outdir)))),\ + $(eval include $(filter-out $(_at.included_makefiles),$(makefile))))) + +# This bit only gets evaluated once, after all of the other Makefiles are read +ifeq ($(_at.NO_ONCE),) + +outdir = /bogus +srcdir = /bogus + +$(foreach v,$(at.dirlocal),$(eval $v=)) + +include $(call _at.reverse,$(sort $(wildcard $(topsrcdir)/build-aux/Makefile.once.tail/*.mk))) + +endif # _at.NO_ONCE diff --git a/build-aux/write-ifchanged b/build-aux/write-ifchanged new file mode 100755 index 0000000..185ceb0 --- /dev/null +++ b/build-aux/write-ifchanged @@ -0,0 +1,25 @@ +#!/usr/bin/env bash +# Copyright (C) 2015 Luke Shumaker +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU Affero General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Affero General Public License for more details. +# +# You should have received a copy of the GNU Affero General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +outfile=$1 +tmpfile="$(dirname "$outfile")/.tmp${outfile##*/}" + +cat > "$tmpfile" || exit $? +if cmp -s "$tmpfile" "$outfile"; then + rm -f "$tmpfile" || : +else + mv -f "$tmpfile" "$outfile" +fi |