spkg-configure.m4 for iconv

[embray]

In general the iconv SPKG is not even required. It's not installed (or rather, a dummy empty package is installed) for any platforms except Cygwin, HP-UX, and Solaris.

The requirement for it on Cygwin is probably outdated--iconv is a standard library on almost all Cygwin installations, and is surely more up-to-date than when this SPKG was first added in #8567. Support for the other two platforms has not been maintained much.

We can add a configure-time check for it, and treat it as a dummy package in most cases.

[dimpase]

there is a cryptic

    # Disable NLS on Cygwin to be able to build libiconv without the Cygwin
    # libiconv package.

I presume the latter line should be "NLS package", no ?

Does this mean that the Cygwin's "native" libiconv does not work?

[dimpase]

According to #13912, that --disable-nls on Cygwin was dictated by the desire to reduce the number of Cygwin deps. I think it can be scrapped.

[dimpase]

using AM_ICONV (a bit of a hack). Needs config.rpath from gettext. (I also saw packages just creating an empty config.rpath, so perhaps we can do this too).

Does this work on Cygwin?

---

New commits:

​0afc4dc

use AM_ICONV from gettext

[dimpase]

on OSX this also needs lib-link.m4...

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​4ea2241

moar autocon stuff added

[git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

​ff3d5ed

moar autocon stuff added

[git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

​29ca931

moar autocon stuff added

[dimpase]

OK, this much is needed for OSX...

[embray]

For the config.rpath stuff, it seems that file is included with gettext, typically under /usr/share/gettext/config.rpath. Normally it is installed by gettextize, but I don't think we actually want to run that, since we really just want the file; we don't want to prepare the program for direct use of gettext.

I wonder if there's a reasonably reliable way to just get the path to this file...

[dimpase]

the problem is that AM_ICONV pulls in a lot of macros from gettext, so config.rpath is just one of many things needed, as I found out on a gettext-less OSX box...

[embray]

It turns out gettextize is just a shell script, and the path to /usr/share/gettext is just in some variables in that file that are output when gettext is configured.

[embray]

the problem is that AM_ICONV pulls in a lot of macros from gettext

Are you saying you're trying to get it so you can run configure without the macros from gettext? The thing about config.rpath is that it's not a macro; it's just a file that needs to be copied into place. automake and the like don't do this automatically for the most part.

[dimpase]

Replying to embray:

the problem is that AM_ICONV pulls in a lot of macros from gettext

Are you saying you're trying to get it so you can run configure without the macros from gettext? The thing about config.rpath is that it's not a macro; it's just a file that needs to be copied into place. automake and the like don't do this automatically for the most part.

that's correct, all of this is just to use AM_ICONV. On OSX iconv is provided by the system, no need for gettext (or iconv) implementation; however AM_ICONV is a part of gettext package, and has several deps there, that need to be installed (and some of these deps need config.rpath script installed into the right place).

[embray]

Apparently it's actually a macro called AC_LIB_RPATH that requires the config.rpath file, and it happens to be used indirectly by AM_ICONV. Most of the google results for AC_LIB_RPATH relate to this problem.

[dimpase]

Ha! Where is my medal?! Cf. Paul Eggert saying that only brave people use AM_ICONV directly: ​https://lists.gnu.org/archive/html/autoconf/2002-09/msg00181.html

[embray]

I think this mostly just comes down to a misconfiguration on many distributions.

automake has a "libdir" that it searches for these generated files that it copies into your project. For example on my system my automake libdir is /usr/share/automake-1.14 in which I have I have:

$ ls -l /usr/share/automake-1.14
total 512
drwxr-xr-x 2 root root   4096 May 26  2016 am
-rwxr-xr-x 1 root root   5826 Jan  2  2014 ar-lib
drwxr-xr-x 2 root root   4096 May 26  2016 Automake
-rwxr-xr-x 1 root root   7333 Jan  2  2014 compile
lrwxrwxrwx 1 root root     20 Jan  2  2014 config.guess -> ../misc/config.guess
lrwxrwxrwx 1 root root     18 Jan  2  2014 config.sub -> ../misc/config.sub
-rw-r--r-- 1 root root  35147 Jan  2  2014 COPYING
-rwxr-xr-x 1 root root  23566 Jan  2  2014 depcomp
-rw-r--r-- 1 root root  15752 Jan  2  2014 INSTALL
-rwxr-xr-x 1 root root  13997 Jan  2  2014 install-sh
-rwxr-xr-x 1 root root   6047 Jan  2  2014 mdate-sh
-rwxr-xr-x 1 root root   6872 Jan  2  2014 missing
-rwxr-xr-x 1 root root   3538 Jan  2  2014 mkinstalldirs
-rwxr-xr-x 1 root root   4670 Jan  2  2014 py-compile
-rwxr-xr-x 1 root root  15285 Jan  2  2014 tap-driver.pl
-rwxr-xr-x 1 root root  19464 Jan  2  2014 tap-driver.sh
-rwxr-xr-x 1 root root   4287 Jan  2  2014 test-driver
-rw-r--r-- 1 root root 323102 Jan  2  2014 texinfo.tex
-rwxr-xr-x 1 root root   6858 Jan  2  2014 ylwrap

As you can see, the commonly used config.guess and config.sub are actually symlinks to /usr/misc. It turns out on my system these files are not even provided by automake, but rather a package called autotools-dev.

For this to work properly the distro ought to be creating a symlink /usr/share/automake-1.14/config.rpath -> ../gettext/config.rpath.

But they don't, so it doesn't get installed properly.

[embray]

Here's a snippet of code I wrote to do what automake should be doing, but in our bootstrap script. Seems to work nicely but have not tried in the MacOS hinterlands...

bootstrap

@@ -28 +28 @@
 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."
+        exit 1
+    fi
+    eval `sed -n '/^prefix=\(.*\)$/p' $gettextize`
+    eval `sed -n '/^datarootdir=\(.*\)$/p' $gettextize`
+    eval `sed -n '/^gettext_dir=\(.*\)$/p' $gettextize`
+
+    if [ -z "$gettext_dir" ]; then
+        echo >&2 "Failed to read the gettext_dir directory from $gettextize"
+        echo >&2 "The config.rpath file must manually be copied into config/"
+        echo >&2 "This file is installed with gettext typically in /usr/share/gettext"
+        exit 1
+    fi
+
+    config_rpath="$gettext_dir/config.rpath"
+    if [ ! -f "$config_rpath" ]; then
+        echo >&2 "Missing $config_rpath file; this indicates a broken gettext install."
+        exit 1
+    fi
+
+    echo "bootstrap:$LINENO: installing 'config/config.rpath'"
+    cp "$config_rpath" config/
+}
+
+
+
 bootstrap () {
     rm -f m4/sage_spkg_configures.m4
     spkg_configures=""
@@ -40 +75 @@
     echo "$spkg_configures" >> m4/sage_spkg_configures.m4
 
     aclocal -I m4 && \
+    install_config_rpath && \
     automake --add-missing --copy build/make/Makefile-auto && \
     autoconf

[dimpase]

on my gentoo box I have /usr/share/gettext/config.rpath, yet it does not get picked up, i.e. if I remove the copying of config.rpath from bootstrap I get

$ ./bootstrap 
rm -rf config configure build/make/Makefile-auto.in
configure.ac:320: installing 'config/compile'
configure.ac:105: installing 'config/config.guess'
m4/sage_spkg_configures.m4:35: error: required file 'config/config.rpath' not found
configure.ac:105: installing 'config/config.sub'
configure.ac:68: installing 'config/install-sh'
configure.ac:68: installing 'config/missing'

Apparently it has to installed:

$ grep -R "config.rpath" /usr/share/aclocal
/usr/share/aclocal/guile.m4:  dnl the file gnulib/build-aux/config.rpath.
/usr/share/aclocal/lib-link.m4:  dnl Complain if config.rpath is missing.

/usr/share/aclocal/lib-link.m4:  AC_REQUIRE_AUX_FILE([config.rpath])
/usr/share/aclocal/lib-link.m4:    ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh

Naturally, on a box with gettext and autoconf installed none of these *.m4 files in this branch are needed, but config.path still is needed.

[embray]

Try my patch above. The problem is that automake simply doesn't install the file if it's only found in /usr/share/gettext.

[git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

​be482fd

use AM_ICONV, copy config.rpath from gettext's datadir

[dimpase]

OK, this works with gettext 0.19 and 0.20 (also on OSX, with some extra effort). I had to change /^gettext_dir to /gettext_datadir and replace gettext_dir with gettext_datadir in the rest.

Anyhow, this also needs to be tested on a "clean" OSX, without autotoots, with pre-generated configure, too.

[embray]

Except this won't work on my gettext where it's spelled "gettext_dir".

[embray]

I guess mine must be quite old: ​https://github.com/autotools-mirror/gettext/commit/ff18897068486560e2bb421004cfbd42b7cdd0f8

This will still need to be reworked a bit. It's maddening that the tool doesn't just have like a --print-gettext-dir option.

[embray]

This works in both versions:

eval `sed -n '/^prefix=.*$/p' $gettextize`
eval `sed -n '/^datarootdir=.*$/p' $gettextize`
eval `sed -n '/^gettext_dir=.*$/p' $gettextize`
if [ -z "$gettext_dir" ]; then
    # In newer versions this is spelled gettext_datadir
    eval `sed -n '/^: \${gettext_datadir=.*$/p' $gettextize`
    gettext_dir="$gettext_datadir"
fi

Also simplified a bit from my old version where I left in some groupings in the sed regexp that were not actually used.

[dimpase]

Replying to embray:

I guess mine must be quite old: ​https://github.com/autotools-mirror/gettext/commit/ff18897068486560e2bb421004cfbd42b7cdd0f8

This will still need to be reworked a bit. It's maddening that the tool doesn't just have like a --print-gettext-dir option.

Well, one can try to ask for it, but then it would need to get approved by Ulrich Drepper, it seems...

[dimpase]

Replying to embray:

This works in both versions:

eval `sed -n '/^prefix=.*$/p' $gettextize`
eval `sed -n '/^datarootdir=.*$/p' $gettextize`
eval `sed -n '/^gettext_dir=.*$/p' $gettextize`
if [ -z "$gettext_dir" ]; then
    # In newer versions this is spelled gettext_datadir
    eval `sed -n '/^: \${gettext_datadir=.*$/p' $gettextize`
    gettext_dir="$gettext_datadir"
fi

Also simplified a bit from my old version where I left in some groupings in the sed regexp that were not actually used.

well, this is out of sync with the ticket branch - but feel free to do your own version!

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​0bb824e

Support versions of gettext older than 2014-04-21

[embray]

Replying to dimpase:

well, this is out of sync with the ticket branch - but feel free to do your own version!

I went ahead and updated the branch. Perhaps it's a little unnecessary to support much older versions, but it at least came up on one machine which I'd like to keep working for now.

[dimpase]

It's fine, sure - but did you test this branch on old gettext? It seems to me that you need else clause to if [ -z "$gettext_dir" ]; then doing

   gettext_datadir="$gettext_dir"

[embray]

Oh yeah, you're right. This is a little messed up now.

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​57efc6f

Reworked to prefer gettext_datadir (for newer gettexts) and fall back to gettext_dir only for older versions.

[embray]

I think this is good now. Tested on both versions.

Also tested this on Cygwin and confirmed (as expected) that it works well using the system iconv (thank you!)

[mjo]

Is gettext guaranteed to be installed for some reason? If not, maybe we can punt and add it to the list at

​http://doc.sagemath.org/html/en/installation/source.html#command-line-tools

[dimpase]

gettext, just like autotools, is needed to run ./bootstrap; none of this is documented, though. We should, though...

[vbraun]

install_config_rpath calls exit(1) in some code paths, but its supposed to fall back to downloading the confball...

[git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

​fdad7d9	use AM_ICONV, copy config.rpath from gettext's datadir
​7f8d72d	Support versions of gettext older than 2014-04-21
​bf2479d	Reworked to prefer gettext_datadir (for newer gettexts) and fall back to gettext_dir only for older versions.
​1604b82	return in install_rpath_config; analyse its result

[dimpase]

rebased, added returns, removed exits

[git]

Branch pushed to git repo; I updated commit sha1. New commits:

​f79ccf9

do not run aclocal before we tried gettex, and correct return code

[dimpase]

ok, so this works without gettext installed (some funny thing with the return code, I return 779 and receive 11)

on a broken gettext install, with absent AM_ICONV, bootstrap -d would still fail.

Do we care about the latter?

[dimpase]

Correction: it does work in the latter scenario.

[git]

Branch pushed to git repo; I updated commit sha1 and set ticket back to needs_review. New commits:

​2b5ceb1

return must be between 0 and 255

[dimpase]

renumbered the return code to be between 0 and 255.

[embray]

It seems that, at least on Cygwin, AM_ICONV will pass, somehow, even if iconv.h is installed, thus making the libicon-devel package on Cygwin a requirement, at least when it comes to building R (which otherwise fails at #include <iconv.h>).

For now I'll just update the Cygwin build instructions to require libiconv-devel as a prerequisite which is preferable anyways. But maybe this still needs to be checked for somehow...

[embray]

ping slelievre for first discovering this.

[dimpase]

maybe add AC_CHECK_HEADER for iconv.h ?

[embray]

That's what I'm thinking, though now I need to double-check what AM_ICONV is actually doing, since I'm surprised it doesn't seem to need to do that...

[dimpase]

to get this working on OSX's home-brew, do

brew install gettext
brew link gettext --force

[mkoeppe]

Follow up: #29532

[dimpase]

Bruno Haible says on ​bug-autoconf that one should use gnulib's iconv module to install config.rpath etc. Indeed,

gnulib-tool --import iconv

will install config.rpath into config/ (among with other things that probably can be ignored). So this is something to try in order to get rid of the hacky install_config_rpath() in comment:18

[mkoeppe]

I have added this remark to #29549.