Create system wide config.{guess,sub} scripts

[Pavel Raiskup]

(cc-ing automake mailing list)

Hi all, do you think that there would be possible to cover upstream
creation of system wide config.{sub,guess} scripts?  Possible patch
is at the bottom of this mail.

Nothing would change from the target-project point of view - just that if
the user's distribution distributes these sys-wide scripts, they are going
to be called instead of the ones distributed by `make dist`-created
tarball (in a case the --time-stamp output of sys-wide script is newer).
Even the direct download of config.guess/config.sub files stays unchanged
(for automake and other project purposes).

The problem this patch solves is that there is a lot of packages
containing non-up2date config.{guess,sub} scripts copied during autoconf
phase from automake distribution.  Thus, when distribution decides to e.g.
support new architecture which is already covered by config.guess/sub
upstream, it must patch whole bunch of packages replacing those scripts.

Distros are able to deal with this problem on the packaging system site
- but every distro then must improve their packaging system to
automatically replace those scripts... and such upstream-like solution
would help to all distributions globally.

If you agree with these changes (and no obvious consequences are seen),
I'll be able to clean/improve things in proposed patch - and write some
README file suggesting how to package gnuconfig (the
sys.config.{sub,guess} scripts are intended to reside in users $PATH).

Thanks for discussion,
Pavel

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..44c744e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+sys.config.guess
+sys.config.sub
diff --git a/ChangeLog b/ChangeLog
index 0e49c17..9685e2b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2013-04-05  Pavel Raiskup  <address@hidden>
+
+       * config.guess: Allow running the system-wide version of this
+       script when existent.
+       * config.sub: Likewise.
+       * Makefile: Generate new sys.config.guess and sys.config.sub
+       scripts.
+       * .gitignore: New file.
+
 2013-02-12  Christian Svensson  <address@hidden>
 
        * config.guess (or1k:Linux:*:*): New.
diff --git a/Makefile b/Makefile
index 5d8a2bb..98df7c7 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-all:
+all: sys-scripts
 
 check: check-guess check-sub
 
@@ -7,3 +7,20 @@ check-guess:
 
 check-sub:
        cd testsuite && sh config-sub.sh
+
+sys-scripts: sys.config.guess sys.config.sub
+
+SYS_CONF_SUB=sys.config.sub
+SYS_CONF_GUESS=sys.config.guess
+CLEANER=sed "/\# == try to run system-wide script ==/,/try_run_sys='yes'/{d}"
+
+$(SYS_CONF_GUESS): config.guess
+       $(CLEANER) config.guess > $(SYS_CONF_GUESS)
+       chmod +x $(SYS_CONF_GUESS)
+
+$(SYS_CONF_SUB): config.sub
+       $(CLEANER) config.sub > $(SYS_CONF_SUB)
+       chmod +x $(SYS_CONF_SUB)
+
+clean:
+       rm -rf $(SYS_CONF_GUESS) $(SYS_CONF_SUB)
diff --git a/config.guess b/config.guess
index f475ceb..e5ea362 100755
--- a/config.guess
+++ b/config.guess
@@ -2,7 +2,7 @@
 # Attempt to guess a canonical system name.
 #   Copyright 1992-2013 Free Software Foundation, Inc.
 
-timestamp='2013-02-12'
+timestamp='2013-04-05'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -31,6 +31,15 @@ timestamp='2013-02-12'
 #
 # Please send patches with a ChangeLog entry to address@hidden
 
+# == try to run system-wide script ==
+#
+# This script is trying to search for a system-wide version of itself and
+# run it instead.  The system-wide script is run only if its timestamp is
+# newer then the one specified at top of this script.  This behaviour is
+# possible to suppress by setting the following variable to 'no'.
+try_run_sys='yes'
+
+sys_script_name='sys.config.guess'
 
 me=`echo "$0" | sed -e 's,.*/,,'`
 
@@ -84,6 +93,17 @@ if test $# != 0; then
   exit 1
 fi
 
+# try to run system-wide script
+if test "x$try_run_sys" = "xyes"; then
+  if command -v $sys_script_name >/dev/null; then
+    sys_timestamp=`$sys_script_name --time-stamp`
+    if test $timestamp '<' $sys_timestamp; then
+      $sys_script_name
+      exit $?
+    fi
+  fi
+fi
+
 trap 'exit 1' 1 2 15
 
 # CC_FOR_BUILD -- compiler used by this script. Note that the use of a
diff --git a/config.sub b/config.sub
index 872199a..b58f7ba 100755
--- a/config.sub
+++ b/config.sub
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2013 Free Software Foundation, Inc.
 
-timestamp='2013-02-12'
+timestamp='2013-04-05'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -50,6 +50,16 @@ timestamp='2013-02-12'
 #      CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM
 # It is wrong to echo any other type of specification.
 
+# == try to run system-wide script ==
+#
+# This script is trying to search for a system-wide version of itself and
+# run it instead.  The system-wide script is run only if its timestamp is
+# newer then the one specified at top of this script.  This behaviour is
+# possible to suppress by setting the following variable to 'no'.
+try_run_sys='yes'
+
+sys_script_name='sys.config.sub'
+
 me=`echo "$0" | sed -e 's,.*/,,'`
 
 usage="\
@@ -111,6 +121,17 @@ case $# in
     exit 1;;
 esac
 
+# try to run system-wide script
+if test "x$try_run_sys" = "xyes"; then
+  if command -v $sys_script_name >/dev/null; then
+    sys_timestamp=`$sys_script_name --time-stamp`
+    if test $timestamp '<' $sys_timestamp; then
+      $sys_script_name $1
+      exit $?
+    fi
+  fi
+fi
+
 # Separate what the user gave into CPU-COMPANY and OS or KERNEL-OS (if any).
 # Here we must recognize all the valid KERNEL-OS combinations.
 maybe_os=`echo $1 | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`