conditionally compile support for jack_port_type_get_buffer_size() and if available at compile AND runtime, use it in preference to jack_port_get_buffer_size() during a reconnect to JACK

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@9646 d708f5d6-7413-0410-9779-e7cbd77b26cf

2 files changed, 36 insertions, 2 deletions

diff --git a/libs/ardour/SConscript b/libs/ardour/SConscript
index 5a8303957e..5dcf82a497 100644
--- a/libs/ardour/SConscript
+++ b/libs/ardour/SConscript
@@ -139,6 +139,23 @@ ardour.Append(CXXFLAGS="-DLOCALEDIR=\\\"" + os.path.join (final_prefix, 'share',
 ardour.Merge ([ libraries['jack'] ])
 
 #
+# See if JACK supports jack_port_type_get_buffer_size()
+#
+jack_port_type_buffer_size_source_file = """
+#include <jack/jack.h>
+int main(int argc, char **argv)
+{
+    jack_port_type_get_buffer_size (0, JACK_DEFAULT_AUDIO_TYPE);
+    return 0;
+}
+"""
+def CheckJackPortTypeGetBufferSize(context):
+        context.Message('Checking for jack_port_type_get_buffer_size()...')
+        result = context.TryLink(jack_port_type_buffer_size_source_file, '.c')
+        context.Result(result)
+        return result
+
+#
 # See if JACK supports jack_client_open()
 #
 
@@ -236,12 +253,16 @@ conf = Configure(ardour, custom_tests = {
 	'CheckJackOnInfoShutdown' : CheckJackOnInfoShutdown,
 	'CheckJackRecomputeLatencies' : CheckJackRecomputeLatencies,
 	'CheckJackVideoFrameOffset' : CheckJackVideoFrameOffset,
-	'CheckJackEnsureMonitorInput' : CheckJackEnsureMonitorInput
+	'CheckJackEnsureMonitorInput' : CheckJackEnsureMonitorInput,
+	'CheckJackPortTypeGetBufferSize' : CheckJackPortTypeGetBufferSize
 })
 
 if conf.CheckJackClientOpen():
 	ardour.Append(CXXFLAGS="-DHAVE_JACK_CLIENT_OPEN")
 
+if conf.CheckJackPortTypeGetBufferSize():
+	ardour.Append(CXXFLAGS="-DHAVE_JACK_PORT_TYPE_GET_BUFFER_SIZE")
+
 if conf.CheckJackOnInfoShutdown():
 	ardour.Append(CXXFLAGS="-DHAVE_JACK_ON_INFO_SHUTDOWN")
 
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index fe5de6dc82..5501f76e79 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -1249,7 +1249,20 @@ AudioEngine::reconnect_to_jack ()
 
 	if (session) {
 		session->reset_jack_connection (_priv_jack);
-		nframes_t blocksize = jack_get_buffer_size (_priv_jack);
+                
+                nframes_t blocksize;
+
+#ifdef HAVE_JACK_PORT_TYPE_GET_BUFFER_SIZE
+                if (jack_port_type_get_buffer_size) {
+                        blocksize = jack_port_type_get_buffer_size (_priv_jack, JACK_DEFAULT_AUDIO_TYPE);
+                } else {
+                        warning << _("This version of JACK is old - you should upgrade to a newer version that supports jack_port_type_get_buffer_size()") << endmsg;
+                        blocksize = jack_get_buffer_size (_priv_jack);
+                }
+#else
+                blocksize = jack_get_buffer_size (_priv_jack);
+#endif
+                
 		Port::set_buffer_size (blocksize);
 		session->set_block_size (blocksize);
 		session->set_frame_rate (jack_get_sample_rate (_priv_jack));