AS_VERSION_COMPARE

[Derek Price]

I've attached a patch to add AS_VERSION_COMPARE(VERSION-1, VERSION-2,
[ACTION-IF-LESS], [ACTION-IF-EQUAL], [ACTION-IF-GREATER]) to M4sh.  CVS
has been using it for some time to issue warnings when the local version
of zlib being used is older than the system version and vice versa.

If no one objects, I will commit it.

2005-06-16  Derek Price  <address@hidden>

    * lib/m4sugar/m4sh.m4 (AS_VERSION_COMPARE): New function.

Regards,

Derek


Index: lib/m4sugar/m4sh.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/m4sugar/m4sh.m4,v
retrieving revision 1.146
diff -u -p -r1.146 m4sh.m4
--- lib/m4sugar/m4sh.m4 11 Jun 2005 06:05:12 -0000      1.146
+++ lib/m4sugar/m4sh.m4 16 Jun 2005 13:45:38 -0000
@@ -1022,6 +1022,52 @@ _AS_PATH_WALK([$PATH], [echo "PATH: $as_
 }])
 
 
+# AS_VERSION_COMPARE(VERSION-1, VERSION-2,
+#                    [ACTION-IF-LESS], [ACTION-IF-EQUAL], [ACTION-IF-GREATER])
+# -----------------------------------------------------------------------------
+# Compare two strings possibly containing shell variables as version strings.
+AC_DEFUN([AS_VERSION_COMPARE],
+[if test "x[$1]" = "x[$2]"; then
+  # the strings are equal.  run ACTION-IF-EQUAL and bail
+  m4_default([$4], :)
+m4_ifvaln([$3$5], [else
+  # first unletter the versions
+  # this only works for a single trailing letter
+  dnl echo has a double-quoted arg to allow for shell expansion.
+  as_version_1=`echo "[$1]" |
+                 sed 's/\([abcedfghi]\)/.\1/;
+                      s/\([jklmnopqrs]\)/.1\1/;
+                      s/\([tuvwxyz]\)/.2\1/;
+                      
y/abcdefghijklmnopqrstuvwxyz/12345678901234567890123456/;'`
+  as_version_2=`echo "[$2]" |
+                 sed 's/\([abcedfghi]\)/.\1/;
+                      s/\([jklmnopqrs]\)/.1\1/;
+                      s/\([tuvwxyz]\)/.2\1/;
+                      
y/abcdefghijklmnopqrstuvwxyz/12345678901234567890123456/;'`
+  as_count=1
+  as_save_IFS=$IFS
+  IFS=.
+  as_retval=-1
+  for vsub1 in $as_version_1; do
+    vsub2=`echo "$as_version_2" |awk -F. "{print \\\$$as_count}"`
+    if test -z "$vsub2" || test $vsub1 -gt $vsub2; then
+      as_retval=1
+      break
+    elif test $vsub1 -lt $vsub2; then
+      break
+    fi
+    as_count=`expr $as_count + 1`
+  done
+  IFS=$as_save_IFS
+  if test $as_retval -eq -1; then
+    m4_default([$3], :)
+  m4_ifval([$5], [else
+$5])
+  fi])
+fi
+]) # AS_VERSION_COMPARE
+
+
 # AS_HELP_STRING(LHS, RHS, [COLUMN])
 # ----------------------------------
 #

Index: lib/m4sugar/m4sh.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/m4sugar/m4sh.m4,v
retrieving revision 1.146
diff -u -p -r1.146 m4sh.m4
--- lib/m4sugar/m4sh.m4 11 Jun 2005 06:05:12 -0000      1.146
+++ lib/m4sugar/m4sh.m4 16 Jun 2005 13:45:38 -0000
@@ -1022,6 +1022,52 @@ _AS_PATH_WALK([$PATH], [echo "PATH: $as_
 }])
 
 
+# AS_VERSION_COMPARE(VERSION-1, VERSION-2,
+#                    [ACTION-IF-LESS], [ACTION-IF-EQUAL], [ACTION-IF-GREATER])
+# -----------------------------------------------------------------------------
+# Compare two strings possibly containing shell variables as version strings.
+AC_DEFUN([AS_VERSION_COMPARE],
+[if test "x[$1]" = "x[$2]"; then
+  # the strings are equal.  run ACTION-IF-EQUAL and bail
+  m4_default([$4], :)
+m4_ifvaln([$3$5], [else
+  # first unletter the versions
+  # this only works for a single trailing letter
+  dnl echo has a double-quoted arg to allow for shell expansion.
+  as_version_1=`echo "[$1]" |
+                 sed 's/\([abcedfghi]\)/.\1/;
+                      s/\([jklmnopqrs]\)/.1\1/;
+                      s/\([tuvwxyz]\)/.2\1/;
+                      
y/abcdefghijklmnopqrstuvwxyz/12345678901234567890123456/;'`
+  as_version_2=`echo "[$2]" |
+                 sed 's/\([abcedfghi]\)/.\1/;
+                      s/\([jklmnopqrs]\)/.1\1/;
+                      s/\([tuvwxyz]\)/.2\1/;
+                      
y/abcdefghijklmnopqrstuvwxyz/12345678901234567890123456/;'`
+  as_count=1
+  as_save_IFS=$IFS
+  IFS=.
+  as_retval=-1
+  for vsub1 in $as_version_1; do
+    vsub2=`echo "$as_version_2" |awk -F. "{print \\\$$as_count}"`
+    if test -z "$vsub2" || test $vsub1 -gt $vsub2; then
+      as_retval=1
+      break
+    elif test $vsub1 -lt $vsub2; then
+      break
+    fi
+    as_count=`expr $as_count + 1`
+  done
+  IFS=$as_save_IFS
+  if test $as_retval -eq -1; then
+    m4_default([$3], :)
+  m4_ifval([$5], [else
+$5])
+  fi])
+fi
+]) # AS_VERSION_COMPARE
+
+
 # AS_HELP_STRING(LHS, RHS, [COLUMN])
 # ----------------------------------
 #