Re-do Lua detection

Detect LuaJIT first, then other implementations. Allows setting
`--with-lua` to a specific implementation as well (e.g. `lua51`). Will
produce errors appropriately.

Fixes PowerDNS#6423.

build-scripts/build-auth-rpm

@@ -696,7 +696,7 @@ export CPPFLAGS="-DLDAP_DEPRECATED"
 	--disable-dependency-tracking \
 	--disable-silent-rules \
 	--with-modules='' \
-	--with-luajit \
+	--with-lua=luajit \
 	--with-dynmodules='%{backends} random' \
 	--enable-tools \
 	--enable-libsodium \

build-scripts/build-dnsdist-rpm

@@ -46,7 +46,7 @@ SNMP_CONFIGURE='--with-net-snmp \'
 
 # CentOS 6 has no luajit
 LUA_BUILDREQUIRES='BuildRequires: luajit-devel'
-LUA_CONFIGURE='--with-luajit \'
+LUA_CONFIGURE='--with-lua=luajit \'
 
 # These two are the same for sysv and systemd (we don't install defaults files at the moment)
 DEFAULTS_INSTALL=''

build-scripts/build-recursor-rpm

@@ -237,7 +237,7 @@ package if you need a dns cache for your network.
 	--with-protobuf \
 	--enable-libsodium \
 	--with-net-snmp \
-	--with-luajit \
+	--with-lua=luajit \
 	--enable-systemd
 
 make %{?_smp_mflags}

build-scripts/debian-authoritative/rules

@@ -52,7 +52,7 @@ override_dh_auto_configure:
 		--with-modules="" \
 		--enable-tools \
 		--enable-unit-tests \
-		--with-luajit \
+		--with-lua=luajit \
 		--enable-experimental-pkcs11 \
 		$(ENABLE_SYSTEMD) \
 		$(ENABLE_LIBSODIUM)

build-scripts/debian-dnsdist/rules

@@ -65,7 +65,7 @@ override_dh_auto_configure:
 	  --libexecdir='$${prefix}/lib' \
 	  --with-protobuf=yes \
 	  --with-net-snmp \
-	  --with-luajit \
+	  --with-lua=luajit \
 	  $(ENABLE_SYSTEMD) \
 	  $(ENABLE_RE2) \
 	  $(ENABLE_LIBSODIUM)

build-scripts/debian-recursor/rules

@@ -62,7 +62,7 @@ override_dh_auto_configure:
 		--infodir=\$${prefix}/share/info \
 		--libdir='$${prefix}/lib/$(DEB_HOST_MULTIARCH)' \
 		--libexecdir='$${prefix}/lib' \
-		--with-luajit \
+		--with-lua=luajit \
 		--with-protobuf=yes \
 		$(ENABLE_NETSNMP) \
 		$(ENABLE_SYSTEMD) \

configure.ac

@@ -43,10 +43,7 @@ m4_pattern_forbid([^_?PKG_[A-Z_]+$], [*** pkg.m4 missing, please install pkg-con
 
 PDNS_CHECK_OS
 
-PDNS_WITH_LUAJIT
-AS_IF([test "x$with_luajit" = "xno"], [
-  PDNS_WITH_LUA
-])
+PDNS_WITH_LUA
 PDNS_CHECK_LUA_HPP
 
 AX_CXX_COMPILE_STDCXX_11
@@ -207,7 +204,7 @@ for a in $modules $dynmodules; do
       AS_IF([test "x$with_lua" = "xno"],
         AC_MSG_ERROR([Lua backend needs lua, run ./configure --with-lua])
       )
-      AS_IF([test "x$LUAPC" = "x" -a "x$LUAJITPC" = "x"],
+      AS_IF([test "x$LUAPC" = "x"],
         AC_MSG_ERROR([Lua backend needs lua but we cannot find it])
       )
       ;;

m4/pdns_check_lua_hpp.m4

@@ -1,7 +1,6 @@
 AC_DEFUN([PDNS_CHECK_LUA_HPP],[
   AC_REQUIRE([PDNS_WITH_LUA])
-  AC_REQUIRE([PDNS_WITH_LUAJIT])
-  AS_IF([test "x$LUAPC" != "x" -o "x$LUAJITPC" != "x" ], [
+  AS_IF([test "x$LUAPC" != "x" ], [
     AC_CHECK_HEADER([lua.hpp], [ have_lua_hpp=y ])
   ])
   AM_CONDITIONAL([HAVE_LUA_HPP], [ test x"$have_lua_hpp" = "xy" ])

m4/pdns_with_lua.m4

@@ -1,36 +1,48 @@
 AC_DEFUN([PDNS_WITH_LUA],[
-  AC_MSG_CHECKING([whether we will be linking in Lua])
-  AC_ARG_WITH([lua],
-    [AS_HELP_STRING([--with-lua], [build Lua Bindings @<:@default=auto@:>@])],
-    [with_lua=$withval],
-    [with_lua=auto]
-  )
+  AC_MSG_CHECKING([which Lua implementation to use])
+  AC_ARG_WITH([lua], [
+    AS_HELP_STRING([--with-lua], [select Lua implementation @<:@default=auto@:>@])
+  ], [
+    with_lua=$withval
+  ], [
+    with_lua=auto
+  ])
   AC_MSG_RESULT([$with_lua])
 
-  AS_IF([test "x$with_lua" != "xno"],[
-    AS_IF([test "x$with_lua" = "xyes" -o "x$with_lua" = "xauto"],
-      [for LUAPC in lua5.3 lua-5.3 lua53 lua5.2 lua-5.2 lua52 lua5.1 lua-5.1 lua51 lua; do
-         PKG_CHECK_MODULES([LUA], $LUAPC >= 5.1, [
-           AC_DEFINE([HAVE_LUA], [1], [Define to 1 if you have lua])
-           with_lua=yes
-         ], [LUAPC=""]) # otherwise pkg_check will fail
-         if test "x$LUA_LIBS" != "x"; then break; fi
-       done
-      ],
-      [LUAPC="$with_lua"
-        PKG_CHECK_MODULES([LUA], $LUAPC >= 5.1, [
-          AC_DEFINE([HAVE_LUA], [1], [Define to 1 if you have lua])
-          with_lua=yes
+  AS_IF([test "x$with_lua" = "xno" -a "$1" = "mandatory"], [
+    AC_MSG_ERROR([--without-lua specified, but Lua is not optional])
+  ])
+
+  LUAPC=""
+
+  AS_IF([test "x$with_lua" != "xno"], [
+    AS_IF([test "x$with_lua" != "xauto"], [
+      PKG_CHECK_MODULES([LUA], $with_lua >= 5.1, [
+        AC_DEFINE([HAVE_LUA], [1], [Define to 1 if you have Lua])
+        LUAPC=$with_lua
+      ], [
+        AC_MSG_ERROR([Selected Lua not found])
+      ])
+    ], [
+      PKG_CHECK_MODULES([LUA], [luajit], [LUAPC=luajit], [ : ])
+      AS_IF([test -z "$LUAPC"], [
+        found_lua=n
+        m4_foreach_w([luapc], [lua5.3 lua-5.3 lua53 lua5.2 lua-5.2 lua52 lua5.1 lua-5.1 lua51 lua], [
+          AS_IF([test "$found_lua" != "y"], [
+            PKG_CHECK_MODULES([LUA], luapc >= 5.1, [
+              AC_DEFINE([HAVE_LUA], [1], [Define to 1 if you have lua])
+              found_lua=y
+              LUAPC=luapc
+            ], [ : ])
+          ])
         ])
-    ])
-    AC_MSG_CHECKING([for chosen LUA])
-    AS_IF([test "x$LUAPC" = "x"], [
-      AS_IF([test "x$with_lua" = "xyes"],
-        [AC_MSG_ERROR([cannot find lua])],
-        [AC_MSG_RESULT([not found])]
-      )],[
-        AC_MSG_RESULT([$LUAPC])
       ])
     ])
-  AM_CONDITIONAL([LUA], [test "x$with_lua" = "xyes"])
+  ])
+
+  AS_IF([test -z "$LUAPC" -a "$1" = "mandatory"], [
+    AC_MSG_ERROR([No Lua not found, but is mandatory])
+  ])
+
+  AM_CONDITIONAL([LUA], [test -n "x$LUAPC"])
 ])

pdns/dnsdistdist/configure.ac

@@ -42,13 +42,7 @@ AM_CONDITIONAL([HAVE_SYSTEMD], [ test x"$systemd" = "xy" ])
 AC_SUBST([YAHTTP_CFLAGS], ['-I$(top_srcdir)/ext/yahttp'])
 AC_SUBST([YAHTTP_LIBS], ['$(top_builddir)/ext/yahttp/yahttp/libyahttp.la'])
 
-PDNS_WITH_LUAJIT
-AS_IF([test "x$with_luajit" = "xno"], [
-  PDNS_WITH_LUA
-])
-AS_IF([test "x$LUAPC" = "x" -a "x$LUAJITPC" = "x"], [
-  AC_MSG_ERROR([Neither Lua nor LuaJIT found, Lua support is not optional])
-])
+PDNS_WITH_LUA([mandatory])
 PDNS_CHECK_LUA_HPP
 
 DNSDIST_ENABLE_DNS_OVER_TLS
@@ -125,12 +119,7 @@ AC_MSG_NOTICE([BOOST_CPPFLAGS: $BOOST_CPPFLAGS])
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([Features enabled])
 AC_MSG_NOTICE([----------------])
-AS_IF([test "x$LUAPC" != "x"],
-  [AC_MSG_NOTICE([Lua: $LUAPC])],
-  [AS_IF([test "x$LUAJITPC" != "x"],
-    [AC_MSG_NOTICE([LuaJit: $LUAJITPC])],
-    [AC_MSG_NOTICE([Lua/LuaJit: no])])
-])
+AC_MSG_NOTICE([Lua: $LUAPC])
 AS_IF([test "x$PROTOBUF_LIBS" != "x" -a x"$PROTOC" != "x"],
   [AC_MSG_NOTICE([Protobuf: yes])],
   [AC_MSG_NOTICE([Protobuf: no])]

pdns/recursordist/configure.ac

@@ -99,13 +99,7 @@ PDNS_SELECT_CONTEXT_IMPL
 PDNS_ENABLE_UNIT_TESTS
 PDNS_ENABLE_REPRODUCIBLE
 
-PDNS_WITH_LUAJIT
-AS_IF([test "x$with_luajit" = "xno"], [
-  PDNS_WITH_LUA
-])
-AS_IF([test "x$LUAPC" = "x" -a "x$LUAJITPC" = "x"], [
-  AC_MSG_ERROR([Neither Lua nor LuaJIT found, Lua support is not optional])
-])
+PDNS_WITH_LUA([mandatory])
 PDNS_CHECK_LUA_HPP
 
 PDNS_ENABLE_VERBOSE_LOGGING
@@ -206,12 +200,7 @@ AC_MSG_NOTICE([BOOST_CPPFLAGS: $BOOST_CPPFLAGS])
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([Features enabled])
 AC_MSG_NOTICE([----------------])
-AS_IF([test "x$LUAPC" != "x"],
-  [AC_MSG_NOTICE([Lua: $LUAPC])],
-  [AS_IF([test "x$LUAJITPC" != "x"],
-    [AC_MSG_NOTICE([LuaJit: $LUAJITPC])],
-    [AC_MSG_NOTICE([Lua/LuaJit: no])])
-])
+AC_MSG_NOTICE([Lua: $LUAPC])
 AC_MSG_NOTICE([OpenSSL ECDSA: $libcrypto_ecdsa])
 AS_IF([test "x$LIBSODIUM_LIBS" != "x"],
   [AC_MSG_NOTICE([libsodium ed25519: yes])],