Find out the etags program and use it in Makefile (M. Mondor)

src/Makefile.in

@@ -18,6 +18,7 @@ LDFLAGS	= @LDFLAGS@
 RM	= @RM@
 LN_S	= @LN_S@
 EXE	= @EXEEXT@
+ETAGS	= @ETAGS@
 
 # ==================== Where To Install Things ====================
 
@@ -246,9 +247,10 @@ selfbuild:
 # This rule is allowed to fail when etags does not exist.
 TAGS:
 	echo > $@;
+	test $ETAGS && \
 	-srcfiles=`find $(srcdir)/c/ $(srcdir)/h/ -name '*.[chd]'`; \
-	etags --language=c    -o $@ $$srcfiles && \
-	etags --language=none -o $@ --append \
+	$ETAGS --language=c    -o $@ $$srcfiles && \
+	$ETAGS --language=none -o $@ --append \
 	      --regex='/@\([-:*a-zA-z]+\)/\1/' \
 	      --regex='/@(defun \([-:*a-zA-z]+\)/\1/' \
 	      $$srcfiles

src/configure

@@ -649,6 +649,7 @@ RM
 CP
 true_builddir
 true_srcdir
+ETAGS
 AR
 SET_MAKE
 LN_S
@@ -4610,6 +4611,48 @@ else
   AR="$ac_cv_prog_AR"
 fi
  # set variable AR to appropriate `ar' program
+for ac_prog in etags emacs-etags
+do
+  # Extract the first word of "$ac_prog", so it can be a program name with args.
+set dummy $ac_prog; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_prog_ETAGS+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  if test -n "$ETAGS"; then
+  ac_cv_prog_ETAGS="$ETAGS" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if { test -f "$as_dir/$ac_word$ac_exec_ext" && $as_test_x "$as_dir/$ac_word$ac_exec_ext"; }; then
+    ac_cv_prog_ETAGS="$ac_prog"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi
+fi
+ETAGS=$ac_cv_prog_ETAGS
+if test -n "$ETAGS"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ETAGS" >&5
+$as_echo "$ETAGS" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+  test -n "$ETAGS" && break
+done
+ # set variable ETAGS to etags program if found
 
 
 

src/configure.in

@@ -326,6 +326,7 @@ AC_PROG_LN_S          # sets variable LN_S
 AC_PROG_MAKE_SET      # set $(MAKE) if needed
 AC_PROG_RANLIB        # set variable RANLIB
 AC_CHECK_TOOL([AR],[ar]) # set variable AR to appropriate `ar' program
+AC_CHECK_PROGS([ETAGS],[etags emacs-etags]) # set variable ETAGS to etags program if found
 
 dnl -----------------------------------------------------------------------
 dnl Checks which do not come with autoconf (must be after AC_PROG_CC)