automatically generate version info from git HEAD

.gitignore

@@ -1 +1,2 @@
 lfs-bootscripts-*.tar.xz
+version.ent

Makefile

@@ -119,7 +119,7 @@ tmpdir:
 	$(Q)rm -f $(RENDERTMP)/*md5sum*
 	$(Q)rm -f $(RENDERTMP)/*pdf.fo
 
-validate: tmpdir
+validate: tmpdir version
 	@echo "Processing bootscripts..."
 	$(Q)bash process-scripts.sh
 
@@ -187,6 +187,9 @@ $(BASEDIR)/md5sums: stylesheets/wget-list.xsl chapter03/chapter03.xml \
        "s/BOOTSCRIPTS-MD5SUM/$(shell md5sum lfs-bootscripts*.tar.xz | cut -d' ' -f1)/" \
        $(BASEDIR)/md5sums
 
+version:
+	$(Q)./git-version.sh
+
 #dump-commands: validate
 #	@echo "Dumping book commands..."
 #	$(Q)xsltproc --nonet                     \
@@ -204,5 +207,5 @@ $(BASEDIR)/md5sums: stylesheets/wget-list.xsl chapter03/chapter03.xml \
 
 all: book nochunks pdf # dump-commands
 
-.PHONY : all book dump-commands nochunks pdf profile-html tmpdir validate md5sums wget-list
+.PHONY : all book dump-commands nochunks pdf profile-html tmpdir validate md5sums wget-list version
 

chapter01/changelog.xml

@@ -42,6 +42,7 @@
     <listitem revision="sysv"> or <listitem revision="systemd"> as
     appropriate for the entry or if needed the entire day's listitem.
     -->
+
     <listitem>
       <para>2021-03-26</para>
       <itemizedlist>

general.ent

@@ -1,16 +1,25 @@
-<!ENTITY version         "SVN-20210326">
+<!-- version info automatically generated by git
+     comment the following two lines for release -->
+<!ENTITY % version-entities SYSTEM "version.ent">
+%version-entities;
+
+<!-- uncomment and edit the following four lines
+     for releases (including -rc) -->
+<!--
+<!ENTITY version         "10.2-rc1">
+<!ENTITY versiond        "10.2-rc1">
+<!ENTITY releasedate     "August 26th, 2021">
+<!ENTITY copyrightdate   "1999-2021">
+-->
+<!-- jhalfs needs a literal dash, not &ndash; -->
+
 <!ENTITY short-version   "svn">  <!-- Used below in &blfs-book; 
                                       Change to x.y for release but not -rc releases -->
 <!ENTITY generic-version "development"> <!-- Use "development"  or "x.y[-pre{x}]" -->
 
-<!ENTITY versiond        "20210326-systemd">
 <!ENTITY short-versiond  "systemd">
 <!ENTITY generic-versiond "systemd"> 
 
-<!ENTITY releasedate     "March 26th, 2021">
-
-<!ENTITY copyrightdate   "1999-2021"><!-- jhalfs needs a literal dash, not &ndash; -->
-
 <!ENTITY lfs-root        "http://www.linuxfromscratch.org/">
 <!ENTITY blfs-root       "&lfs-root;blfs/">
 <!ENTITY blfs-book       "&blfs-root;view/&short-version;/">

git-version.sh

@@ -0,0 +1,45 @@
+#!/bin/sh
+
+if ! git status; then
+	# Either it's not a git repository, or git is unavaliable.
+	# Just workaround.
+	echo "<!ENTITY version           \"unknown\">"         >  version.ent
+	echo "<!ENTITY versiond          \"unknown-systemd\">" >> version.ent
+	echo "<!ENTITY releasedate       \"unknown\">"         >> version.ent
+	echo "<!ENTITY copyrightdate     \"1999-2021\">"       >> version.ent
+	exit 0
+fi
+
+export LC_ALL=en_US.utf8
+export TZ=US/Pacific
+
+commit_date=$(git show -s --format=format:"%cd" --date=local)
+short_date=$(date --date "$commit_date" "+%Y%m%d")
+
+year=$(date --date "$commit_date" "+%Y")
+month=$(date --date "$commit_date" "+%B")
+month_digit=$(date --date "$commit_date" "+%m")
+day=$(date --date "$commit_date" "+%d")
+
+case $day in
+	"1" | "21" | "31" ) suffix="st";;
+	"2" | "22" ) suffix="nd";;
+	"3" | "23" ) suffix="rd";;
+	* ) suffix="th";;
+esac
+
+full_date="$month $day$suffix, $year"
+
+sha="g$(git describe --always)"
+version="GIT-$short_date-$sha"
+versiond="GIT-$short_date-$sha-systemd"
+
+if [ "$(git diff HEAD | wc -l)" != "0" ]; then
+	version="$version-MODIFIED"
+	versiond="$versiond-MODIFIED"
+fi
+
+echo "<!ENTITY version           \"$version\">"            >  version.ent
+echo "<!ENTITY versiond          \"$versiond\">"           >> version.ent
+echo "<!ENTITY releasedate       \"$full_date\">"          >> version.ent
+echo "<!ENTITY copyrightdate     \"1999-$year\">"          >> version.ent