fix(userspace/falco): do not start webserver in capture mode.

Signed-off-by: Federico Di Pierro <nierro92@gmail.com>

userspace/falco/app_actions/start_webserver.cpp

@@ -25,8 +25,7 @@ using namespace falco::app;
 application::run_result application::start_webserver()
 {
 	run_result ret;
-
+	if(!is_capture_mode() && m_state->config->m_webserver_enabled)
-	if(m_state->config->m_webserver_enabled)
 	{
 		std::string ssl_option = (m_state->config->m_webserver_ssl_enabled ? " (SSL)" : "");
 		falco_logger::log(LOG_INFO, "Starting internal webserver, listening on port " + to_string(m_state->config->m_webserver_listen_port) + ssl_option + "\n");
@@ -36,14 +35,15 @@ application::run_result application::start_webserver()
 			m_state->config->m_webserver_ssl_certificate, 
 			m_state->config->m_webserver_ssl_enabled);
 	}
-
 	return ret;
 }
 
 bool application::stop_webserver(std::string &errstr)
+{
+	if(!is_capture_mode())
 	{
 		m_state->webserver.stop();
-
+	}
 	return true;
 }
 

userspace/falco/application.cpp

@@ -29,8 +29,6 @@ using namespace std::placeholders;
 namespace falco {
 namespace app {
 
-std::string application::s_syscall_source = falco_common::syscall_source;
-
 application::run_result::run_result()
 	: success(true), errstr(""), proceed(true)
 {
@@ -44,7 +42,7 @@ application::state::state()
 	: restart(false),
 	  terminate(false),
 	  reopen_outputs(false),
-	  enabled_sources({application::s_syscall_source})
+	  enabled_sources({falco_common::syscall_source})
 {
 	config = std::make_shared<falco_configuration>();
 	outputs = std::make_shared<falco_outputs>();
@@ -130,8 +128,8 @@ bool application::run(std::string &errstr, bool &restart)
 		std::bind(&application::create_signal_handlers, this),
 		std::bind(&application::load_config, this),
 		std::bind(&application::init_inspector, this),
-		std::bind(&application::init_falco_engine, this),
 		std::bind(&application::load_plugins, this),
+		std::bind(&application::init_falco_engine, this),
 		std::bind(&application::list_fields, this),
 		std::bind(&application::list_plugins, this),
 		std::bind(&application::load_rules_files, this),

userspace/falco/application.h

@@ -52,15 +52,12 @@ public:
 	bool run(std::string &errstr, bool &restart);
 
 private:
-	static std::string s_syscall_source;
-
 	// Holds the state used and shared by the below methods that
 	// actually implement the application. Declared as a
 	// standalone class to allow for a bit of separation between
 	// application state and instance variables, and to also defer
 	// initializing this state until application::init.
-	class state {
+	struct state {
-	public:
 		state();
 		virtual ~state();
 
@@ -74,23 +71,15 @@ private:
 		std::shared_ptr<sinsp> inspector;
 		std::set<std::string> enabled_sources;
 
-		// The event sources that correspond to "syscall"
+		// The event source index that correspond to "syscall"
 		std::size_t syscall_source_idx;
 
-		// The event source actually used to process events in
-		// process_events(). Will generally be
-		// syscall_source_idx, or a plugin index if plugins
-		// are loaded.
-		std::size_t event_source_idx;
-
-		std::list<sinsp_plugin::info> plugin_infos;
-
 		// All filterchecks created by plugins go in this
 		// list. If we ever support multiple event sources at
 		// the same time, this, and the factories created in
 		// init_inspector/load_plugins, will have to be a map
 		// from event source to filtercheck list.
-		filter_check_list plugin_filter_checks;
+		std::map<std::string, filter_check_list> plugin_filter_checks;
 
 		std::map<string,uint64_t> required_engine_versions;
 
@@ -165,10 +154,17 @@ private:
 			    uint64_t duration_to_tot_ns,
 			    run_result &result);
 	
-	// This could probably become a direct object once lua is
+	inline bool is_syscall_source_enabled() const 
-	// removed from falco. Currently, creating any global
+	{
-	// application object results in a crash in
+		return m_state->enabled_sources.find(falco_common::syscall_source)
-	// falco_common::init(), as it loads all lua modules.
+			!= m_state->enabled_sources.end();
+	}
+
+	inline bool is_capture_mode() const 
+	{
+		return !m_options.trace_filename.empty();
+	}
+
 	std::unique_ptr<state> m_state;
 	cmdline_options m_options;
 	bool m_initialized;