1 files changed, 45 insertions, 0 deletions
diff --git a/m4/vl_lib_readline.m4 b/m4/vl_lib_readline.m4
new file mode 100644
index 0000000..f95be7b
--- /dev/null
+++ b/m4/vl_lib_readline.m4
@@ -0,0 +1,45 @@
+AC_DEFUN([VL_LIB_READLINE], [
+  AC_CACHE_CHECK([for a readline compatible library],
+                 vl_cv_lib_readline, [
+    ORIG_LIBS="$LIBS"
+    for readline_lib in readline edit editline; do
+      for termcap_lib in "" termcap curses ncurses; do
+        if test -z "$termcap_lib"; then
+          TRY_LIB="-l$readline_lib"
+        else
+          TRY_LIB="-l$readline_lib -l$termcap_lib"
+        fi
+        LIBS="$ORIG_LIBS $TRY_LIB"
+        AC_TRY_LINK_FUNC(readline, vl_cv_lib_readline="$TRY_LIB")
+        if test -n "$vl_cv_lib_readline"; then
+          break
+        fi
+      done
+      if test -n "$vl_cv_lib_readline"; then
+        break
+      fi
+    done
+    if test -z "$vl_cv_lib_readline"; then
+      vl_cv_lib_readline="no"
+      LIBS="$ORIG_LIBS"
+    fi
+  ])
+
+  if test "$vl_cv_lib_readline" != "no"; then
+    LIBREADLINE="$vl_cv_lib_readline"
+    AC_DEFINE(HAVE_LIBREADLINE, 1,
+              [Define if you have a readline compatible library])
+    AC_CHECK_HEADERS(readline.h readline/readline.h)
+    AC_CACHE_CHECK([whether readline supports history],
+                   [vl_cv_lib_readline_history], [
+      vl_cv_lib_readline_history="no"
+      AC_TRY_LINK_FUNC([add_history], [vl_cv_lib_readline_history="yes"])
+    ])
+    if test "$vl_cv_lib_readline_history" = "yes"; then
+      AC_DEFINE(HAVE_READLINE_HISTORY, 1,
+                [Define if your readline library has \`add_history'])
+      AC_CHECK_HEADERS(history.h readline/history.h)
+    fi
+  fi
+  AC_SUBST(LIBREADLINE)
+])dnl