From 8c6bb8a236441f0c31c5127c478a0e5be01d41df Mon Sep 17 00:00:00 2001
From: Henri DF <henridf@gmail.com>
Date: Fri, 4 Mar 2016 17:53:39 -0800
Subject: [PATCH] Set Lua cpath along with path

---
 README.md                       |  2 --
 userspace/digwatch/digwatch.cpp | 34 ++++++++++++++++++++++++++++++++-
 userspace/digwatch/rules.cpp    | 20 +------------------
 userspace/digwatch/rules.h      |  3 +--
 4 files changed, 35 insertions(+), 24 deletions(-)

diff --git a/README.md b/README.md
index aea72ffc..da9fbd41 100644
--- a/README.md
+++ b/README.md
@@ -33,8 +33,6 @@ $ make
 
 as a result, you should have a digwatch executable `build/userspace/digwatch/digwatch`.
 
-Still not quite done yet! we need to install the [lpeg](http://www.inf.puc-rio.br/~roberto/lpeg/) Lua library. (This should be done automatically as part of the build of course...). To install it, just do: `luarocks install lpeg`.
-
 
 ### Running
 
diff --git a/userspace/digwatch/digwatch.cpp b/userspace/digwatch/digwatch.cpp
index 98a22e7a..0a010c8a 100644
--- a/userspace/digwatch/digwatch.cpp
+++ b/userspace/digwatch/digwatch.cpp
@@ -125,6 +125,37 @@ void do_inspect(sinsp* inspector,
 	}
 }
 
+void add_lua_path(lua_State *ls, string path)
+{
+	string cpath = string(path);
+	path += "?.lua";
+	cpath += "?.so";
+
+	lua_getglobal(ls, "package");
+
+	lua_getfield(ls, -1, "path");
+	string cur_path = lua_tostring(ls, -1 );
+	cur_path += ';';
+	lua_pop(ls, 1);
+
+	cur_path.append(path.c_str());
+
+	lua_pushstring(ls, cur_path.c_str());
+	lua_setfield(ls, -2, "path");
+
+	lua_getfield(ls, -1, "cpath");
+	string cur_cpath = lua_tostring(ls, -1 );
+	cur_cpath += ';';
+	lua_pop(ls, 1);
+
+	cur_cpath.append(cpath.c_str());
+
+	lua_pushstring(ls, cur_cpath.c_str());
+	lua_setfield(ls, -2, "cpath");
+
+	lua_pop(ls, 1);
+}
+
 //
 // ARGUMENT PARSING AND PROGRAM SETUP
 //
@@ -241,8 +272,9 @@ int digwatch_init(int argc, char **argv)
 		// Initialize Lua interpreter
 		ls = lua_open();
 		luaL_openlibs(ls);
+		add_lua_path(ls, lua_dir);
 
-		rules = new digwatch_rules(inspector, ls, lua_main_filename, lua_dir);
+		rules = new digwatch_rules(inspector, ls, lua_main_filename);
 
 		digwatch_formats::init(inspector, ls);
 		digwatch_fields::init(inspector, ls);
diff --git a/userspace/digwatch/rules.cpp b/userspace/digwatch/rules.cpp
index 97fcda16..f93b875d 100644
--- a/userspace/digwatch/rules.cpp
+++ b/userspace/digwatch/rules.cpp
@@ -7,33 +7,15 @@ extern "C" {
 }
 
 
-digwatch_rules::digwatch_rules(sinsp* inspector, lua_State *ls, string lua_main_filename, string lua_dir)
+digwatch_rules::digwatch_rules(sinsp* inspector, lua_State *ls, string lua_main_filename)
 {
 	m_ls = ls;
 
 	m_lua_parser = new lua_parser(inspector, m_ls);
 
-	add_lua_path(lua_dir);
 	load_compiler(lua_main_filename);
 }
 
-void digwatch_rules::add_lua_path(string path)
-{
-	path += "?.lua";
-
-	lua_getglobal(m_ls, "package");
-	lua_getfield(m_ls, -1, "path");
-
-	string cur_path = lua_tostring(m_ls, -1 );
-	cur_path += ';';
-
-	cur_path.append(path.c_str());
-	lua_pop(m_ls, 1);
-
-	lua_pushstring(m_ls, cur_path.c_str());
-	lua_setfield(m_ls, -2, "path");
-	lua_pop(m_ls, 1);
-}
 
 void digwatch_rules::load_compiler(string lua_main_filename)
 {
diff --git a/userspace/digwatch/rules.h b/userspace/digwatch/rules.h
index 91e7adb2..366a9c1e 100644
--- a/userspace/digwatch/rules.h
+++ b/userspace/digwatch/rules.h
@@ -6,13 +6,12 @@
 class digwatch_rules
 {
  public:
-	digwatch_rules(sinsp* inspector, lua_State *ls, string lua_main_filename, string lua_dir);
+	digwatch_rules(sinsp* inspector, lua_State *ls, string lua_main_filename);
 	~digwatch_rules();
 	void load_rules(string rules_filename);
 	sinsp_filter* get_filter();
 
  private:
-	void add_lua_path(string path);
 	void load_compiler(string lua_main_filename);
 
 	lua_parser* m_lua_parser;