From be86e43e2202a45307535564c0458e5ffe86af6e Mon Sep 17 00:00:00 2001
From: Florian Eckert <fe@dev.tdt.de>
Date: Thu, 24 Jan 2019 13:53:17 +0100
Subject: [PATCH 1/2] collectd: enable lua support

This will enable the lua support for collectd.
The new package name is collectd-mod-lua

Signed-off-by: Florian Eckert <fe@dev.tdt.de>
---
 utils/collectd/Makefile | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/utils/collectd/Makefile b/utils/collectd/Makefile
index 71dee4285..9084f515a 100644
--- a/utils/collectd/Makefile
+++ b/utils/collectd/Makefile
@@ -53,7 +53,6 @@ COLLECTD_PLUGINS_DISABLED:= \
 	ipvs \
 	java \
 	log_logstash \
-	lua \
 	lvm \
 	lpar \
 	madwifi \
@@ -138,6 +137,7 @@ COLLECTD_PLUGINS_SELECTED:= \
 	iwinfo \
 	load \
 	logfile \
+	lua \
 	match_empty_counter \
 	match_hashed \
 	match_regex \
@@ -196,7 +196,11 @@ endef
 
 define Package/collectd
 $(call Package/collectd/Default)
-  DEPENDS:= +libpthread +zlib +libltdl +libip4tc
+  DEPENDS:= +libpthread \
+	  +zlib \
+	  +libltdl \
+	  +libip4tc \
+	  +PACKAGE_collectd-mod-lua:liblua
   MENU:=1
 endef
 
@@ -226,7 +230,12 @@ CONFIGURE_ARGS+= \
 CONFIGURE_VARS+= \
 	CFLAGS="$$$$CFLAGS $(FPIC)" \
 	LDFLAGS="$$$$LDFLAGS -lm -lz" \
-	KERNEL_DIR="$(LINUX_DIR)" \
+	KERNEL_DIR="$(LINUX_DIR)"
+
+ifneq ($(CONFIG_PACKAGE_collectd-mod-lua),)
+CONFIGURE_VARS+= \
+	LDFLAGS="$$$$LDFLAGS -llua"
+endif
 
 ifneq ($(CONFIG_PACKAGE_COLLECTD_ENCRYPTED_NETWORK),)
 CONFIGURE_ARGS+= \
@@ -360,6 +369,7 @@ $(eval $(call BuildPlugin,irq,interrupt usage input,irq,))
 $(eval $(call BuildPlugin,iwinfo,libiwinfo wireless statistics,iwinfo,+PACKAGE_collectd-mod-iwinfo:libiwinfo))
 $(eval $(call BuildPlugin,load,system load input,load,))
 $(eval $(call BuildPlugin,logfile,log files output,logfile,))
+$(eval $(call BuildPlugin,lua,lua input/output,lua,+PACKAGE_collectd-mod-lua:liblua))
 $(eval $(call BuildPlugin,match-empty-counter,empty-counter match,match_empty_counter,))
 $(eval $(call BuildPlugin,match-hashed,hashed match,match_hashed,))
 $(eval $(call BuildPlugin,match-regex,regex match,match_regex,))

From 30db5cc1c17424acaaaee24366e57ca7e704b484 Mon Sep 17 00:00:00 2001
From: Florian Eckert <fe@dev.tdt.de>
Date: Tue, 19 Feb 2019 10:25:58 +0100
Subject: [PATCH 2/2] collectd: fix lua callback registration

If you want to register more than one lua plugin, you cannot start the
collectd.

You get always the error message:

"The read function "lua/(null)" is already registered. Check for
duplicates in your configuration!"

This is not what I expect and what the documenation says.
With this change it is now possible to registrate more then one lua
Script.

See https://github.com/collectd/collectd/pull/2379

Signed-off-by: Florian Eckert <fe@dev.tdt.de>
---
 .../930-fix-lua-callback-registration.patch   | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 utils/collectd/patches/930-fix-lua-callback-registration.patch

diff --git a/utils/collectd/patches/930-fix-lua-callback-registration.patch b/utils/collectd/patches/930-fix-lua-callback-registration.patch
new file mode 100644
index 000000000..bffe656e0
--- /dev/null
+++ b/utils/collectd/patches/930-fix-lua-callback-registration.patch
@@ -0,0 +1,42 @@
+--- a/src/lua.c
++++ b/src/lua.c
+@@ -281,9 +281,6 @@ static int lua_cb_register_read(lua_Stat
+ 
+   luaL_checktype(L, 1, LUA_TFUNCTION);
+ 
+-  char function_name[DATA_MAX_NAME_LEN];
+-  snprintf(function_name, sizeof(function_name), "lua/%s", lua_tostring(L, 1));
+-
+   int callback_id = clua_store_callback(L, 1);
+   if (callback_id < 0)
+     return luaL_error(L, "%s", "Storing callback function failed");
+@@ -298,6 +295,9 @@ static int lua_cb_register_read(lua_Stat
+   if (cb == NULL)
+     return luaL_error(L, "%s", "calloc failed");
+ 
++  char function_name[DATA_MAX_NAME_LEN];
++  snprintf(function_name, sizeof(function_name), "lua/%p", thread);
++
+   cb->lua_state = thread;
+   cb->callback_id = callback_id;
+   cb->lua_function_name = strdup(function_name);
+@@ -325,9 +325,6 @@ static int lua_cb_register_write(lua_Sta
+ 
+   luaL_checktype(L, 1, LUA_TFUNCTION);
+ 
+-  char function_name[DATA_MAX_NAME_LEN] = "";
+-  snprintf(function_name, sizeof(function_name), "lua/%s", lua_tostring(L, 1));
+-
+   int callback_id = clua_store_callback(L, 1);
+   if (callback_id < 0)
+     return luaL_error(L, "%s", "Storing callback function failed");
+@@ -342,6 +339,9 @@ static int lua_cb_register_write(lua_Sta
+   if (cb == NULL)
+     return luaL_error(L, "%s", "calloc failed");
+ 
++  char function_name[DATA_MAX_NAME_LEN] = "";
++  snprintf(function_name, sizeof(function_name), "lua/%p", thread);
++
+   cb->lua_state = thread;
+   cb->callback_id = callback_id;
+   cb->lua_function_name = strdup(function_name);