library dialog: catch exception and behave appropriately

gtk2_ardour/library_download_dialog.cc

@@ -39,7 +39,7 @@ using namespace ARDOUR;
 using std::string;
 
 LibraryDownloadDialog::LibraryDownloadDialog ()
-	: ArdourDialog (_("Loop Library Manager"), true) /* modal */
+	: ArdourDialog (_("Loop Download Manager"), true) /* modal */
 	, inflater(0)
 {
 	_model = Gtk::ListStore::create (_columns);
@@ -208,8 +208,14 @@ LibraryDownloadDialog::download (Gtk::TreePath const & path)
 {
 	Gtk::TreeModel::iterator row = _model->get_iter (path);
 	std::string url = (*row)[_columns.url];
+	PBD::Downloader* downloader;
 
-	PBD::Downloader* downloader = new PBD::Downloader (url, ARDOUR::Config->get_clip_library_dir());
+	try {
+		downloader = new PBD::Downloader (url, ARDOUR::Config->get_clip_library_dir());
+	} catch (...) {
+		(*row)[_columns.install] = _("Error");
+		return;
+	}
 
 	/* setup timer callback to update progressbar */
 

libs/pbd/downloader.cc

@@ -16,11 +16,16 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include <cstring>
+#include <cerrno>
+
 #include <glib/gstdio.h>
 
 #include <glibmm/fileutils.h>
 #include <glibmm/miscutils.h>
 
+#include "pbd/compose.h"
+#include "pbd/failed_constructor.h"
 #include "pbd/downloader.h"
 #include "pbd/error.h"
 #include "pbd/i18n.h"
@@ -64,6 +69,17 @@ Downloader::Downloader (string const & u, string const & dir)
 	, _download_size (0)
 	, _downloaded (0)
 {
+	if (!Glib::file_test (destdir, Glib::FILE_TEST_EXISTS)) {
+		if (g_mkdir_with_parents (destdir.c_str(), 0700) != 0) {
+			error << string_compose (_("Could not create clip library dir %1 (%2)"), destdir, strerror(errno)) << endmsg;
+			throw failed_constructor();
+		}
+	} else {
+		if (!Glib::file_test (destdir, Glib::FILE_TEST_IS_DIR)) {
+			error << string_compose (_("Clip library dir (%1) is not a directory"), destdir) << endmsg;
+			throw failed_constructor();
+		}
+	}
 }
 
 Downloader::~Downloader ()