Re: Erroneus error message or what?

[Werner LEMBERG]

> Lately, building lilypond, I have occationally encountered a strange
> error-massage:
> 
> ERROR: Please install required programs: /usr/local/bin/fontforge >=
> 20110222 (installed: 3ec845c4fe718af4908ce2dc25b66d0594930)
> 
> BUT: There IS installed a version of fontforge (with the quoted hash,
> at the specified location, and it is definitely newer than 2011):

Exactly this is the problem: LilyPond's configure script doesn't
properly parse the current fontforge version string.

> In the long run this is an insecure situation. Can it be remedied?

Well, I guess that fontforge will provide a `normalized' version
string as soon as there is a new, official release – right now, the
current FontForge test releases are *really* far from stable.  Until
then, you might try the attached patch.[*]


    Werner


[*] This patch was rejected because of philosophical reasons (to which
    I agree basically).  However, I don't have time to improve it.

>From 995a2a66f0919d13ecae255f854ceedfe83c4172 Mon Sep 17 00:00:00 2001
From: Werner Lemberg <address@hidden>
Date: Fri, 26 Jul 2013 23:29:29 +0200
Subject: [PATCH] [stepmake] Rewrite STEPMAKE_GET_VERSION.

The old version wasn't able to handle current git versions of fontforge
correctly: fontforge now emits different version data to both stderr and
stdout which confused the macro (it erroneously caught the git commit ID
instead of the date).
---
 aclocal.m4 | 75 +++++++++++++++++++++++++++++++++++++-------------------------
 1 file changed, 45 insertions(+), 30 deletions(-)

diff --git a/aclocal.m4 b/aclocal.m4
index 87d8474..1e7ebf9 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -14,42 +14,57 @@ AC_DEFUN(STEPMAKE_GET_EXECUTABLE, [
     type -p $1 2>/dev/null | tail -n 1 | awk '{print $NF}'
 ])
 
+dnl We use autoconf's diversion support to define a shell function for
+dnl getting a program's version.  This avoids issues with nested `...`
+dnl since $(...), which would allow nesting naturally, is not
+dnl supported in all shells.
 
-# Get version string from executable ($1)
-AC_DEFUN(STEPMAKE_GET_VERSION, [
-    ## "$1" --version 2>&1 | grep -v '^$' | head -n 1 | awk '{print $NF}'
-    ##
-    ## ARG.
-    ## Workaround for broken Debian gcc version string:
-    ##     gcc (GCC) 3.1.1 20020606 (Debian prerelease)
-    ##
-    ## -V: Workaround for python
+m4_divert_push([INIT_PREPARE])
 
-    changequote(<<, >>)#dnl
+changequote(<<, >>)
 
-    ## Assume and hunt for dotted version multiplet.
-    ## use eval trickery, because we cannot use multi-level $() instead of ``
-    ## for compatibility reasons.
+# in: $_test_prog
+# out: $_ver
     
-    ## grab the first version number in  --version output.
-    eval _ver=\"\`("$1" --version || "$1" -V) 2>&1 |
-               grep -E '(^| )[0-9][0-9]*\.[0-9]' |
-               head -n 1 |
-               tr ' ' '\n' |
-               sed 's/\([0-9][0-9]*\.[0-9][0-9.]*\).*/\1/g' |
-               grep -E '(^| )[0-9][0-9]*\.[0-9]' |
-               head -n 1\`\"
-
-    if test -z "$_ver"; then
-        ## If empty, try date [fontforge]
-        eval _ver=\"\`("$1" --version || "$1" -V) 2>&1 | grep '[0-9]\{6,8\}' \
-           | head -n 1 \
-           | sed -e 's/^[^.0-9]*//' -e 's/[^.0-9]*$//'\`\"
-    fi
-    echo "$_ver"
-    changequote([, ])#dnl
+stepmake_get_version ()
+{
+  ## Grab the first version number in --version or -V output.
+  ## First scan stdin, then stderr.
+  __ver=`("$_test_prog" --version 2> /dev/null \
+          || "$_test_prog" -V 2> /dev/null; \
+          "$_test_prog" --version 1> /dev/null \
+          || "$_test_prog" -V 1> /dev/null) 2>&1`
+
+  ## Get dotted version multiplet.
+  _ver=`echo "$__ver" \
+        | tr ' ' '\n' \
+        | grep -E '^[0-9][0-9]*\.[0-9]' \
+        | head -n 1 \
+        | sed 's/\([0-9][0-9]*\.[0-9][0-9.]*\).*/\1/'`
+
+  ## Otherwise, try date consisting of 6-8 digits.
+  if test -z "$_ver"; then
+    _ver=`echo "$__ver" \
+          | tr ' ' '\n' \
+          | grep '^[0-9]\{6,8\}' \
+          | head -n 1 \
+          | sed 's/\([0-9][0-9]*\).*/\1/'`
+  fi
+}
+
+changequote([, ])
+
+m4_divert_pop([INIT_PREPARE])
+
+
+# Get version string from executable ($1)
+AC_DEFUN(STEPMAKE_GET_VERSION, [
+  _test_prog="$1"
+  stepmake_get_version
+  echo "$_ver"
 ])
 
+
 # Calculate simplistic numeric version from version string ($1)
 # As yet, we have no need for something more elaborate.
 AC_DEFUN(STEPMAKE_NUMERIC_VERSION, [
-- 
1.8.1.4