Automatically generate a patched automake if needed, and put instructions in the README about how to use such a patch...

Original commit message from CVS:
Automatically generate a patched automake if needed, and put instructions
in the README about how to use such a patched automake.

README

@@ -13,9 +13,14 @@ autogen.sh to generate the build system files.
 Unfortunately, there is a bug in automake which causes it to use a large
 amount of memory when generating plugins/Makefile.in.  The following patch,
 which you may wish to apply to automake (version 1.4), fixes this problem.
-Alternatively, ensure that you have at least 128Mb of memory on your system,
+It is also fixed in versions of automake 1.4f and later.
+Alternatively, ensure that you have at least 512Mb of memory on your system,
 and be prepared to wait a little while when running automake (or autogen.sh).
 
+The autogen.sh script will automatically detect an unpatched automake and give
+a warning.  It will also generate a patched version of automake in the top
+build directory, which you can use by putting it in a directory in your $PATH
+ahead of the unpatched version of automake.
 
 @@ -2383,8 +2383,8 @@
  	# to all possible directories, and use it.  If DIST_SUBDIRS is
@@ -28,7 +33,3 @@ and be prepared to wait a little while when running automake (or autogen.sh).
  	{
  	    $dist_subdir_name = 'DIST_SUBDIRS';
  	    if (! &variable_defined ('DIST_SUBDIRS'))
-
-
-The automake developers have been notified of this problem, and supplied with
-an equivalent patch against CVS head.

autogen.sh

@@ -63,7 +63,23 @@ EOF
       echo "Detected automake version 1.4 (or near) without patch."
       echo "Your version of automake needs a patch applied in order to operate correctly."
       echo
+      patchedfile="`pwd`/automake"
+      if test -e $patchedfile; then 
+	PATCHED=0
+      else
+        echo "patching..."
+        patch -R -s -f `which automake` <autogen.patch.tmp -o $patchedfile;
+	chmod +x $patchedfile;
+	PATCHED=1
+      fi
+      echo
       echo "***************************************************************************"
+      if test -e $patchedfile; then 
+	if test "x$PATCHED" == "x1"; then
+	  echo "A patched version of automake is available at:"
+	  echo "$patchedfile"
+	fi
+      fi
       echo "You should abort the build now and read the README file for an explanation."
       echo "***************************************************************************"
       echo