lua: change a hard readline dependency into an optional one

This requires patching the source code, as readline is hardcoded
in there.

The rationale is to allow disabling the dependency on a gplv3
component (readline) where that license is blacklisted.

Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/lua/lua/0001-Allow-building-lua-without-readline-on-Linux.patch

@@ -0,0 +1,59 @@
+From 601ef636fc4dfb2af3e7fda88d8ea1c1d92affe4 Mon Sep 17 00:00:00 2001
+From: Alexander Kanavin <alex.kanavin@gmail.com>
+Date: Wed, 2 Oct 2019 17:54:15 +0200
+Subject: [PATCH] Allow building lua without readline on Linux
+
+Upstream-Status: Pending
+Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
+---
+ Makefile      | 2 +-
+ src/Makefile  | 3 +++
+ src/luaconf.h | 5 +++++
+ 3 files changed, 9 insertions(+), 1 deletion(-)
+
+diff --git a/Makefile b/Makefile
+index 119110d..9f6df45 100644
+--- a/Makefile
++++ b/Makefile
+@@ -36,7 +36,7 @@ RM= rm -f
+ # == END OF USER SETTINGS -- NO NEED TO CHANGE ANYTHING BELOW THIS LINE =======
+ 
+ # Convenience platforms targets.
+-PLATS= aix bsd c89 freebsd generic linux macosx mingw posix solaris
++PLATS= aix bsd c89 freebsd generic linux linux-no-readline macosx mingw posix solaris
+ 
+ # What to install.
+ TO_BIN= lua luac
+diff --git a/src/Makefile b/src/Makefile
+index 64c78f7..5c0428a 100644
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -109,6 +109,9 @@ generic: $(ALL)
+ linux:
+ 	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -ldl -lreadline"
+ 
++linux-no-readline:
++	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX_NO_READLINE" SYSLIBS="-Wl,-E -ldl"
++
+ macosx:
+ 	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_MACOSX" SYSLIBS="-lreadline"
+ 
+diff --git a/src/luaconf.h b/src/luaconf.h
+index 9eeeea6..d71ca25 100644
+--- a/src/luaconf.h
++++ b/src/luaconf.h
+@@ -64,6 +64,11 @@
+ #define LUA_USE_READLINE	/* needs some extra libraries */
+ #endif
+ 
++#if defined(LUA_USE_LINUX_NO_READLINE)
++#define LUA_USE_POSIX
++#define LUA_USE_DLOPEN		/* needs an extra library: -ldl */
++#endif
++
+ 
+ #if defined(LUA_USE_MACOSX)
+ #define LUA_USE_POSIX
+-- 
+2.17.1
+

meta-oe/recipes-devtools/lua/lua_5.3.5.bb

@@ -4,9 +4,9 @@ LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://doc/readme.html;beginline=318;endline=352;md5=60aa5cfdbd40086501778d9b6ebf29ee"
 HOMEPAGE = "http://www.lua.org/"
 
-DEPENDS = "readline"
 SRC_URI = "http://www.lua.org/ftp/lua-${PV}.tar.gz;name=tarballsrc \
            file://lua.pc.in \
+           file://0001-Allow-building-lua-without-readline-on-Linux.patch \
            "
 
 # if no test suite matches PV release of Lua exactly, download the suite for the closest Lua release.
@@ -24,18 +24,21 @@ SRC_URI[tarballtest.sha256sum] = "b80771238271c72565e5a1183292ef31bd7166414cd0d4
 
 inherit pkgconfig binconfig ptest
 
+PACKAGECONFIG ??= "readline"
+PACKAGECONFIG[readline] = ",,readline"
+
 UCLIBC_PATCHES += "file://uclibc-pthread.patch"
 SRC_URI_append_libc-uclibc = "${UCLIBC_PATCHES}"
 
 TARGET_CC_ARCH += " -fPIC ${LDFLAGS}"
-EXTRA_OEMAKE = "'CC=${CC} -fPIC' 'MYCFLAGS=${CFLAGS} -DLUA_USE_LINUX -fPIC' MYLDFLAGS='${LDFLAGS}'"
+EXTRA_OEMAKE = "'CC=${CC} -fPIC' 'MYCFLAGS=${CFLAGS} -fPIC' MYLDFLAGS='${LDFLAGS}'"
 
 do_configure_prepend() {
     sed -i -e s:/usr/local:${prefix}:g src/luaconf.h
 }
 
 do_compile () {
-    oe_runmake linux
+    oe_runmake ${@bb.utils.contains('PACKAGECONFIG', 'readline', 'linux', 'linux-no-readline', d)}
 }
 
 do_install () {