From 1cccfa6cc4e40cbf32a5ce9f31b1061ff8a9be7e Mon Sep 17 00:00:00 2001 From: paul Date: Tue, 17 Apr 2007 19:41:07 +0000 Subject: [PATCH] add example client for jack_thread_wait() git-svn-id: svn+ssh://jackaudio.org/trunk/jack@1029 0c269be4-1314-0410-8aa9-9f06e86f4224 --- example-clients/Makefile.am | 6 ++ example-clients/tw.c | 202 ++++++++++++++++++++++++++++++++++++ 2 files changed, 208 insertions(+) create mode 100644 example-clients/tw.c diff --git a/example-clients/Makefile.am b/example-clients/Makefile.am index da61f74..d510f61 100644 --- a/example-clients/Makefile.am +++ b/example-clients/Makefile.am @@ -41,6 +41,8 @@ bin_PROGRAMS = jack_load \ jack_midisine \ jack_midiseq +noinst_PROGRAMS = jack_thread_wait + if HAVE_SNDFILE # note! jackrec_CFLAGS syntax not supported by automake-1.4 sndfile_cflags = @SNDFILE_CFLAGS@ @@ -69,6 +71,10 @@ jack_metro_SOURCES = metro.c jack_metro_LDFLAGS = @OS_LDFLAGS@ jack_metro_LDADD = ../libjack/libjack.la +jack_thread_wait_SOURCES = tw.c +jack_thread_wait_LDFLAGS = @OS_LDFLAGS@ +jack_thread_wait_LDADD = ../libjack/libjack.la + jack_lsp_SOURCES = lsp.c jack_lsp_LDFLAGS = @OS_LDFLAGS@ jack_lsp_LDADD = ../libjack/libjack.la diff --git a/example-clients/tw.c b/example-clients/tw.c new file mode 100644 index 0000000..348f7af --- /dev/null +++ b/example-clients/tw.c @@ -0,0 +1,202 @@ +/** @file simple_client.c + * + * @brief This simple client demonstrates the basic features of JACK + * as they would be used by many applications. + */ + +#include +#include +#include +#include +#include + +#include + +jack_port_t *input_port; +jack_port_t *output_port; +jack_client_t *client; + +/* a simple state machine for this client */ +volatile enum { + Init, + Run, + Exit +} client_state = Init; + +/** + * The process callback for this JACK application is called in a + * special realtime thread once for each audio cycle. + * + * This client follows a simple rule: when the JACK transport is + * running, copy the input port to the output. When it stops, exit. + */ +int +_process (jack_nframes_t nframes) +{ + jack_default_audio_sample_t *in, *out; + jack_transport_state_t ts = jack_transport_query(client, NULL); + + if (ts == JackTransportRolling) { + + if (client_state == Init) + client_state = Run; + + in = jack_port_get_buffer (input_port, nframes); + out = jack_port_get_buffer (output_port, nframes); + memcpy (out, in, + sizeof (jack_default_audio_sample_t) * nframes); + + } else if (ts == JackTransportStopped) { + + if (client_state == Run) + client_state = Exit; + } + + return 0; +} + +int +process (jack_nframes_t nframes, void* arg) +{ + jack_client_t* client = (jack_client_t*) arg; + + while ((nframes = jack_thread_wait (client, _process (nframes))) != 0); +} + +/** + * JACK calls this shutdown_callback if the server ever shuts down or + * decides to disconnect the client. + */ +void +jack_shutdown (void *arg) +{ + exit (1); +} + +int +main (int argc, char *argv[]) +{ + const char **ports; + const char *client_name; + const char *server_name = NULL; + jack_options_t options = JackNullOption; + jack_status_t status; + + if (argc >= 2) { /* client name specified? */ + client_name = argv[1]; + if (argc >= 3) { /* server name specified? */ + server_name = argv[2]; + options |= JackServerName; + } + } else { /* use basename of argv[0] */ + client_name = strrchr(argv[0], '/'); + if (client_name == 0) { + client_name = argv[0]; + } else { + client_name++; + } + } + + /* open a client connection to the JACK server */ + + client = jack_client_open (client_name, options, &status, server_name); + if (client == NULL) { + fprintf (stderr, "jack_client_open() failed, " + "status = 0x%2.0x\n", status); + if (status & JackServerFailed) { + fprintf (stderr, "Unable to connect to JACK server\n"); + } + exit (1); + } + if (status & JackServerStarted) { + fprintf (stderr, "JACK server started\n"); + } + if (status & JackNameNotUnique) { + client_name = jack_get_client_name(client); + fprintf (stderr, "unique name `%s' assigned\n", client_name); + } + + /* tell the JACK server to call `process()' whenever + there is work to be done. + */ + + jack_set_process_callback (client, process, client); + + /* tell the JACK server to call `jack_shutdown()' if + it ever shuts down, either entirely, or if it + just decides to stop calling us. + */ + + jack_on_shutdown (client, jack_shutdown, 0); + + /* display the current sample rate. + */ + + printf ("engine sample rate: %" PRIu32 "\n", + jack_get_sample_rate (client)); + + /* create two ports */ + + input_port = jack_port_register (client, "input", + JACK_DEFAULT_AUDIO_TYPE, + JackPortIsInput, 0); + output_port = jack_port_register (client, "output", + JACK_DEFAULT_AUDIO_TYPE, + JackPortIsOutput, 0); + + if ((input_port == NULL) || (output_port == NULL)) { + fprintf(stderr, "no more JACK ports available\n"); + exit (1); + } + + /* Tell the JACK server that we are ready to roll. Our + * process() callback will start running now. */ + + if (jack_activate (client)) { + fprintf (stderr, "cannot activate client"); + exit (1); + } + + /* Connect the ports. You can't do this before the client is + * activated, because we can't make connections to clients + * that aren't running. Note the confusing (but necessary) + * orientation of the driver backend ports: playback ports are + * "input" to the backend, and capture ports are "output" from + * it. + */ + + ports = jack_get_ports (client, NULL, NULL, + JackPortIsPhysical|JackPortIsOutput); + if (ports == NULL) { + fprintf(stderr, "no physical capture ports\n"); + exit (1); + } + + if (jack_connect (client, ports[0], jack_port_name (input_port))) { + fprintf (stderr, "cannot connect input ports\n"); + } + + free (ports); + + ports = jack_get_ports (client, NULL, NULL, + JackPortIsPhysical|JackPortIsInput); + if (ports == NULL) { + fprintf(stderr, "no physical playback ports\n"); + exit (1); + } + + if (jack_connect (client, jack_port_name (output_port), ports[0])) { + fprintf (stderr, "cannot connect output ports\n"); + } + + free (ports); + + /* keep running until the transport stops */ + + while (client_state != Exit) { + sleep (1); + } + + jack_client_close (client); + exit (0); +}