Portable wrapper for lex/yacc invocations, by Tom Tromey

<tromey@cygnus.com>, modified by Sergey Poznyakoff <gray@farlep.net>
to replace yy prefixes, so multiple grammers can co-exist.

+#! /bin/sh
+# ylwrap - wrapper for lex/yacc invocations.
+# Copyright 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
+# Written by Tom Tromey <tromey@cygnus.com>.
+# -yy modification by Sergey Poznyakoff <gray@farlep.net>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+# Usage:
+#     ylwrap PROGRAM [ARGS] INPUT [OUTPUT DESIRED]... -- [-yy repl] [ARGS]...
+# * PROGRAM is program to run; options can follow but must start with `-'.
+# * INPUT is the input file
+# * OUTPUT is file PROG generates
+# * DESIRED is file we actually want
+# * ARGS are passed to PROG
+# * Optional -yy introduces the sequence to replace yy prefixes with.
+# Any number of OUTPUT,DESIRED pairs may be used.
+
+# The program to run.
+prog="$1"
+shift
+# Make any relative path in $prog absolute.
+case "$prog" in
+ /* | [A-Za-z]:*) ;;
+ */*) prog="`pwd`/$prog" ;;
+esac
+
+# We also have to accept options here and append them to the program.
+# Why?  Suppose YACC is set to `bison -y'.  Clearly nobody uses
+# ylwrap, or this would have been discovered earlier!
+while :; do
+   case "$1" in
+    -*)
+       prog="$prog $1"
+       shift
+       ;;
+    *)
+       break
+       ;;
+   esac
+done
+
+# The input.
+input="$1"
+shift
+case "$input" in
+ /* | [A-Za-z]:*)
+    # Absolute path; do nothing.
+    ;;
+ *)
+    # Relative path.  Make it absolute.
+    input="`pwd`/$input"
+    ;;
+esac
+
+# The directory holding the input.
+input_dir="`echo $input | sed -e 's,/[^/]*$,,'`"
+# Quote $INPUT_DIR so we can use it in a regexp.
+# FIXME: really we should care about more than `.'.
+input_rx="`echo $input_dir | sed -e 's,\.,\\\.,g'`"
+
+pairlist=
+while test "$#" -ne 0; do
+   if test "$1" = "--"; then
+      shift
+      break
+   fi
+   pairlist="$pairlist $1"
+   shift
+done
+
+if [ $# -ne 0 ]; then
+    if [ "x$1" = "x-yy" ]; then
+	shift
+	if [ $# -eq 0 ]; then 
+		echo "ylwrap: -yy requires an argument"
+		exit 1 
+	fi
+	YYREPL=$1
+	shift
+    fi
+fi    
+
+# FIXME: add hostname here for parallel makes that run commands on
+# other machines.  But that might take us over the 14-char limit.
+dirname=ylwrap$$
+trap "cd `pwd`; rm -rf $dirname > /dev/null 2>&1" 1 2 3 15
+mkdir $dirname || exit 1
+
+cd $dirname
+
+$prog ${1+"$@"} "$input"
+status=$?
+
+if test $status -eq 0; then
+   set X $pairlist
+   shift
+   first=yes
+   # Since DOS filename conventions don't allow two dots,
+   # the DOS version of Bison writes out y_tab.c instead of y.tab.c
+   # and y_tab.h instead of y.tab.h. Test to see if this is the case.
+   y_tab_nodot="no"
+   if test -f y_tab.c || test -f y_tab.h; then
+      y_tab_nodot="yes"
+   fi
+
+   while test "$#" -ne 0; do
+      from="$1"
+      # Handle y_tab.c and y_tab.h output by DOS
+      if test $y_tab_nodot = "yes"; then
+	 if test $from = "y.tab.c"; then
+	    from="y_tab.c"
+	 else
+	    if test $from = "y.tab.h"; then
+	       from="y_tab.h"
+	    fi
+	 fi
+      fi
+      if test -f "$from"; then
+         # If $2 is an absolute path name, then just use that,
+         # otherwise prepend `../'.
+         case "$2" in
+	   /* | [A-Za-z]:*) target="$2";;
+	   *) target="../$2";;
+	 esac
+
+	 # Edit out `#line' or `#' directives.  We don't want the
+	 # resulting debug information to point at an absolute srcdir;
+	 # it is better for it to just mention the .y file with no
+	 # path.
+	 EXPR="/^#/ s,$input_rx/,,"
+	 if [ ! -z "$YYREPL" ]; then
+	    EXPR="$EXPR;s/yy/$YYREPL/g"
+	 fi
+	 sed -e "$EXPR" "$from" > "$target" || status=$?
+      else
+	 # A missing file is only an error for the first file.  This
+	 # is a blatant hack to let us support using "yacc -d".  If -d
+	 # is not specified, we don't want an error when the header
+	 # file is "missing".
+	 if test $first = yes; then
+	    status=1
+	 fi
+      fi
+      shift
+      shift
+      first=no
+   done
+else
+   status=$?
+fi
+
+# Remove the directory.
+cd ..
+rm -rf $dirname
+
+exit $status
+