1 files changed, 55 insertions, 0 deletions
diff --git a/aclocal.m4 b/aclocal.m4
index e1714d8..f9a6450 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -62,3 +62,58 @@ AC_DEFUN([QUILT_COMPAT_PROG_PATH],[
   fi
   AC_SUBST($1)
 ])
+
+dnl Allow configure to specify a specific binary
+dnl This variant is for optional binaries.
+dnl 1: Environment variable
+dnl 2: binary name
+dnl 3: optional list of alternative binary names
+dnl 4: optional list of additional search directories
+AC_DEFUN([QUILT_COMPAT_PROG_PATH_OPT],[
+  AC_ARG_WITH($2, AC_HELP_STRING(
+    [--with-$2], [name of the $2 executable to use]),
+  [
+    if test x"$withval" != xno; then
+      AC_MSG_CHECKING(for $2)
+      $1="$withval"
+      if test -e "$$1"; then
+	if test ! -f "$$1" -a ! -h "$$1" || test ! -x "$$1"; then
+	  AC_MSG_ERROR([$$1 is not an executable file])
+	fi
+      fi
+      AC_MSG_RESULT([$$1])
+      if test ! -e "$$1"; then
+        AC_MSG_WARN([$$1 does not exist])
+      fi
+      COMPAT_SYMLINKS="$COMPAT_SYMLINKS $2"
+    fi
+  ],[
+    m4_if([$3],[],[
+      AC_PATH_PROG($1,$2,,$PATH:$4)
+    ],[
+      AC_PATH_PROGS($1,$3,,$PATH:$4)
+      if test -n "$$1" -a "`expr "$$1" : '.*/\([[^/]]*\)$'`" != "$2"; then
+	COMPAT_SYMLINKS="$COMPAT_SYMLINKS $2"
+      fi
+    ])
+    m4_if([$4],[],[],[
+      if test -n "$$1"; then
+	as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+        for dir in "$4"; do
+          if test "`dirname $$1`" = "$dir"; then
+            COMPAT_SYMLINKS="$COMPAT_SYMLINKS $2"
+	    break
+	  fi
+        done
+	IFS="$as_save_IFS"
+      fi
+    ])
+    if test -z "$$1"; then
+      AC_MSG_WARN([$2 not found, some optional functionalities will be missing])
+    fi
+  ])
+  if test -z "$$1"; then
+    $1=$2
+  fi
+  AC_SUBST($1)
+])