From 0708721b4f9fca3967a6f1c436717ff2aca0baec Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Tue, 25 Feb 2014 13:11:07 +0100
Subject: [PATCH] scan VSTs in background, allow to cancel & timeout

---
 libs/ardour/ardour/plugin_manager.h |  2 ++
 libs/ardour/plugin_manager.cc       |  6 +++++-
 libs/ardour/vst_info_file.cc        | 10 ++++++++--
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/libs/ardour/ardour/plugin_manager.h b/libs/ardour/ardour/plugin_manager.h
index 0806935a26..d8e6b4c5ec 100644
--- a/libs/ardour/ardour/plugin_manager.h
+++ b/libs/ardour/ardour/plugin_manager.h
@@ -56,6 +56,8 @@ class LIBARDOUR_API PluginManager : public boost::noncopyable {
 	void clear_vst_cache ();
 	void clear_vst_blacklist ();
 
+	bool cancelled () { return cancel_scan; }
+
 	int add_windows_vst_directory (std::string dirpath);
 	int add_lxvst_directory (std::string dirpath);
 
diff --git a/libs/ardour/plugin_manager.cc b/libs/ardour/plugin_manager.cc
index 070936add1..c145fd3aa4 100644
--- a/libs/ardour/plugin_manager.cc
+++ b/libs/ardour/plugin_manager.cc
@@ -187,6 +187,7 @@ PluginManager::refresh (bool cache_only)
 {
 	DEBUG_TRACE (DEBUG::PluginManager, "PluginManager::refresh\n");
 	BootMessage (_("Discovering Plugins"));
+	cancel_scan = false;
 
 	ladspa_refresh ();
 #ifdef LV2_SUPPORT
@@ -210,12 +211,13 @@ PluginManager::refresh (bool cache_only)
 
 	PluginListChanged (); /* EMIT SIGNAL */
 	PluginScanMessage(X_("closeme"), "");
+	cancel_scan = false;
 }
 
 void
 PluginManager::cancel_plugin_scan ()
 {
-	// TODO
+	cancel_scan = true;
 }
 
 void
@@ -661,6 +663,7 @@ PluginManager::windows_vst_discover_from_path (string path, bool cache_only)
 
 	if (plugin_objects) {
 		for (x = plugin_objects->begin(); x != plugin_objects->end (); ++x) {
+			if (cancelled()) break;
 			ARDOUR::PluginScanMessage(_("VST"), **x);
 			windows_vst_discover (**x, cache_only);
 		}
@@ -800,6 +803,7 @@ PluginManager::lxvst_discover_from_path (string path, bool cache_only)
 
 	if (plugin_objects) {
 		for (x = plugin_objects->begin(); x != plugin_objects->end (); ++x) {
+			if (cancelled()) break;
 			ARDOUR::PluginScanMessage(_("LXVST"), **x);
 			lxvst_discover (**x, cache_only);
 		}
diff --git a/libs/ardour/vst_info_file.cc b/libs/ardour/vst_info_file.cc
index 8bb3f4aa7a..fac3f199bc 100644
--- a/libs/ardour/vst_info_file.cc
+++ b/libs/ardour/vst_info_file.cc
@@ -52,6 +52,7 @@
 #include "ardour/vst_info_file.h"
 
 #define MAX_STRING_LEN 256
+#define PLUGIN_SCAN_TIMEOUT (600) // in deciseconds
 
 using namespace std;
 
@@ -746,8 +747,13 @@ vstfx_get_info (const char* dllpath, int type, enum VSTScanMode mode)
 			PBD::error << "Cannot launch VST scanner app '" << scanner_bin_path << "': "<< strerror(errno) << endmsg;
 			return infos;
 		} else {
-			// TODO idle loop (emit signal to GUI to call gtk_main_iteration()) check cancel.
-			scanner.wait();
+			int timeout = PLUGIN_SCAN_TIMEOUT;
+			while (scanner.is_running() && --timeout) {
+				ARDOUR::GUIIdle();
+				Glib::usleep (100000);
+				if (ARDOUR::PluginManager::instance().cancelled()) break;
+			}
+			scanner.terminate();
 		}
 		/* re-read index */
 		vstfx_clear_info_list(infos);