Trac #29549: bootstrap: Clean up use of gettextize

See discussion at
Homebrew/homebrew-core#53192

Instead of using `gettextize` at bootstrap time, we just vendor the
files `m4/iconv.m4` and `config/config.rpath` in the source tree.

This is done by using gnulib: `gnulib-tool --import iconv` (and ignoring
all the other files that it is offering us).

URL: https://trac.sagemath.org/29549
Reported by: mkoeppe
Ticket author(s): Matthias Koeppe
Reviewer(s): Dima Pasechnik

.gitignore

@@ -9,7 +9,12 @@
 # Autotools generated files
 /aclocal.m4
 /autom4te.cache/
-/config/
+/config/install-sh
+/config/compile
+/config/config.guess
+/config/config.sub
+/config/install-sh
+/config/missing
 /config.log
 /config.status
 /configure

Makefile

@@ -167,7 +167,7 @@ distclean: build-clean
 # Delete all auto-generated files which are distributed as part of the
 # source tarball
 bootstrap-clean:
-	rm -rf config configure build/make/Makefile-auto.in
+	rm -rf config/install-sh config/compile config/config.guess config/config.sub config/missing configure build/make/Makefile-auto.in
 	rm -f src/doc/en/installation/*.txt
 	rm -rf src/doc/en/reference/spkg/*.rst
 	rm -f environment.yml

bootstrap

@@ -33,50 +33,6 @@ PKG=build/pkgs/configure
 MAKE="${MAKE:-make}"
 CONFVERSION=$(cat $PKG/package-version.txt)
 
-install_config_rpath() {
-    # The file config.rpath which comes from gettext is supposed to be
-    # installed by automake, but due to a bug in most distros it is not;
-    # see https://trac.sagemath.org/ticket/27823#comment:17
-    #
-    # Here we need to determine where gettext stores its data files and
-    # copy config.rpath from there to config/
-    gettextize="$(command -v gettextize)"
-    if [ -z "$gettextize" ]; then
-        echo >&2 "gettext and the gettextize program must be installed and be in"
-        echo >&2 "your PATH. E.g. Homebrew installs them in /usr/local/opt/gettext/bin."
-        return 179
-    fi
-    eval `sed -n '/^prefix=.*$/p' "$gettextize"`
-    eval `sed -n '/^datarootdir=.*$/p' "$gettextize"`
-    eval `sed -n '/^: \${gettext_datadir=.*$/p' "$gettextize"`
-
-    if [ -z "$gettext_datadir" ]; then
-        eval `sed -n '/^gettext_dir=.*$/p' "$gettextize"`
-        # In older versions (before 2014) this is spelled gettext_dir
-        # See https://github.com/autotools-mirror/gettext/commit/ff18897068486560e2bb421004cfbd42b7cdd0f8
-        gettext_datadir="$gettext_dir"
-    fi
-
-    if [ -z "$gettext_datadir" ]; then
-        echo >&2 "Failed to read the gettext_datadir directory from $gettextize"
-        echo >&2 "The config.rpath file must manually be copied into config/"
-        echo >&2 "This file is installed with gettext typically in /usr/share/gettext"
-        return 179
-    fi
-
-    config_rpath="$gettext_datadir/config.rpath"
-    if [ ! -f "$config_rpath" ]; then
-        echo >&2 "Missing $config_rpath file; this indicates a broken gettext install."
-        return 179
-    fi
-
-    if [ "${BOOTSTRAP_QUIET}" = "no" ]; then
-	echo "bootstrap:$LINENO: installing 'config/config.rpath'"
-    fi
-    cp "$config_rpath" config/
-}
-
-
 
 bootstrap () {
     if [ "${BOOTSTRAP_QUIET}" = "no" ]; then
@@ -160,7 +116,6 @@ SAGE_SPKG_FINALIZE([$pkgname], [$pkgtype], [$SPKG_SOURCE], [$SPKG_TREE_VAR])"
     # third, filter, and then swap them back.
     ./bootstrap-conda && \
     src/doc/bootstrap && \
-    install_config_rpath && \
     aclocal -I m4 && \
     automake --add-missing --copy build/make/Makefile-auto 3>&1 1>&2 2>&3 \
         | sed "${QUIET_SED_FILTER}" 3>&1 1>&2 2>&3 && \
@@ -170,7 +125,7 @@ SAGE_SPKG_FINALIZE([$pkgname], [$pkgtype], [$SPKG_SOURCE], [$SPKG_TREE_VAR])"
     case $st in
         0) true;; # Success
 
-        179|16|63|127)  # install_config_rpath failed|no m4 for pkg-config|autotools not installed|or version too old
+        179|16|63|127)  # no m4 for pkg-config|autotools not installed|or version too old
             if [ $DOWNLOAD = yes ]; then
                 echo >&2 "Bootstrap failed, downloading required files instead."
                 bootstrap_download || exit $?
@@ -182,7 +137,7 @@ SAGE_SPKG_FINALIZE([$pkgname], [$pkgtype], [$SPKG_SOURCE], [$SPKG_TREE_VAR])"
                 else
                     verb="upgrade"
                 fi
-                echo >&2 "Bootstrap failed. Either $verb autotools and gettext; or run bootstrap with"
+                echo >&2 "Bootstrap failed. Either $verb autotools; or run bootstrap with"
                 echo >&2 "the -d option to download the auto-generated files instead."
 
                 SYSTEM=$(build/bin/sage-guess-package-system)
@@ -243,7 +198,7 @@ save () {
     mkdir -p upstream
     tar zcf "$NEWCONFBALL" \
 	configure \
-	config/* \
+	config/install-sh config/compile config/config.guess config/config.sub config/missing \
 	build/make/Makefile-auto.in \
 	src/doc/en/installation/*.txt \
 	src/doc/en/reference/spkg/*.rst \

build/bin/write-dockerfile.sh

@@ -211,6 +211,7 @@ FROM with-system-packages as bootstrapped
 RUN mkdir -p sage
 WORKDIR sage
 $ADD Makefile VERSION.txt COPYING.txt condarc.yml README.md bootstrap bootstrap-conda configure.ac sage .homebrew-build-env tox.ini Pipfile.m4 ./
+$ADD config/config.rpath config/config.rpath
 $ADD src/doc/bootstrap src/doc/bootstrap
 $ADD src/bin src/bin
 $ADD src/Pipfile.m4 src/pyproject.toml.m4 src/requirements.txt.m4 src/setup.cfg.m4 src/VERSION.txt src/