[Jack-Devel] [PATCH 3/3] realtime-safe midi-dump (use ringbuffer)
Signed-off-by: Robin Gareus <[hidden]>
---
example-clients/midi_dump.c | 151 +++++++++++++++++++++++++++----------------
1 file changed, 94 insertions(+), 57 deletions(-)
diff --git a/example-clients/midi_dump.c b/example-clients/midi_dump.c
index 451c826..3785a44 100644
--- a/example-clients/midi_dump.c
+++ b/example-clients/midi_dump.c
@@ -1,51 +1,65 @@
+// gcc -o jack_midi_dump -Wall midi_dump.c -ljack -pthread
+
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <jack/jack.h>
#include <jack/midiport.h>
+#include <jack/ringbuffer.h>
#ifndef WIN32
#include <signal.h>
+#include <pthread.h>
+#include <sys/mman.h>
+#endif
+
+#ifndef MAX
+#define MAX(a,b) ( (a) < (b) ? (b) : (a) )
#endif
static jack_port_t* port;
+static jack_ringbuffer_t *rb = NULL;
+static pthread_mutex_t msg_thread_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t data_ready = PTHREAD_COND_INITIALIZER;
static int keeprunning = 1;
-static int time_format = 0;
-
static uint64_t monotonic_cnt = 0;
-static uint64_t prev_event = 0;
-static void
-describe (jack_midi_event_t* event, char* buffer, size_t buflen)
-{
- assert (buflen > 0);
+#define RBSIZE 512
- buffer[0] = '\0';
+typedef struct {
+ uint8_t buffer[128];
+ uint32_t size;
+ uint32_t tme_rel;
+ uint64_t tme_mon;
+} midimsg;
+static void
+describe (midimsg* event)
+{
if (event->size == 0) {
return;
}
- int type = event->buffer[0] & 0xf0;
- int channel = event->buffer[0] & 0xf;
+ uint8_t type = event->buffer[0] & 0xf0;
+ uint8_t channel = event->buffer[0] & 0xf;
switch (type) {
- case 0x90:
- assert (event->size == 3);
- snprintf (buffer, buflen, "note on (channel %d): pitch %d, velocity %d", channel, event->buffer[1], event->buffer[2]);
- break;
- case 0x80:
- assert (event->size == 3);
- snprintf (buffer, buflen, "note off (channel %d): pitch %d, velocity %d", channel, event->buffer[1], event->buffer[2]);
- break;
- case 0xb0:
- assert (event->size == 3);
- snprintf (buffer, buflen, "control change (channel %d): controller %d, value %d", channel, event->buffer[1], event->buffer[2]);
- break;
- default:
- break;
+ case 0x90:
+ assert (event->size == 3);
+ printf (" note on (channel %2d): pitch %3d, velocity %3d", channel, event->buffer[1], event->buffer[2]);
+ break;
+ case 0x80:
+ assert (event->size == 3);
+ printf (" note off (channel %2d): pitch %3d, velocity %3d", channel, event->buffer[1], event->buffer[2]);
+ break;
+ case 0xb0:
+ assert (event->size == 3);
+ printf (" control change (channel %2d): controller %3d, value %3d", channel, event->buffer[1], event->buffer[2]);
+ break;
+ default:
+ break;
}
}
@@ -55,7 +69,6 @@ process (jack_nframes_t frames, void* arg)
void* buffer;
jack_nframes_t N;
jack_nframes_t i;
- char description[256];
buffer = jack_port_get_buffer (port, frames);
assert (buffer);
@@ -66,34 +79,25 @@ process (jack_nframes_t frames, void* arg)
int r;
r = jack_midi_event_get (&event, buffer, i);
- if (r == 0) {
- size_t j;
- switch(time_format) {
- case 1:
- printf ("%7"PRId64":", event.time + monotonic_cnt);
- break;
- case 2:
- printf ("%+6"PRId64":", event.time + monotonic_cnt - prev_event);
- break;
- default:
- printf ("%4d:", event.time);
- break;
- }
- for (j = 0; j < event.size; ++j) {
- printf (" %x", event.buffer[j]);
- }
-
- describe (&event, description, sizeof (description));
- printf (" %s", description);
+ if (r == 0 && jack_ringbuffer_write_space (rb) >= sizeof(midimsg)) {
+ midimsg m;
+ m.tme_mon = monotonic_cnt;
+ m.tme_rel = event.time;
+ m.size = event.size;
+ memcpy (m.buffer, event.buffer, MAX(sizeof(m.buffer), event.size));
+ jack_ringbuffer_write (rb, (void *) &m, sizeof(midimsg));
- printf ("\n");
- prev_event = event.time + monotonic_cnt;
}
}
monotonic_cnt += frames;
+ if (pthread_mutex_trylock (&msg_thread_lock) == 0) {
+ pthread_cond_signal (&data_ready);
+ pthread_mutex_unlock (&msg_thread_lock);
+ }
+
return 0;
}
@@ -113,14 +117,11 @@ static void usage (int status) {
This tool listens for MIDI events on a JACK MIDI port and prints\n\
the message to stdout.\n\
\n\
-Note that this tool is not realtime-safe. The events are printed\n\
-directly from the process() callback!\n\
-\n\
If no client name is given it defaults to 'midi-monitor'.\n\
\n\
See also: jackd(1)\n\
\n");
- exit (status);
+ exit (status);
}
int
@@ -129,6 +130,7 @@ main (int argc, char* argv[])
jack_client_t* client;
char const default_name[] = "midi-monitor";
char const * client_name;
+ int time_format = 0;
int r;
int cn = 1;
@@ -152,6 +154,8 @@ main (int argc, char* argv[])
exit (EXIT_FAILURE);
}
+ rb = jack_ringbuffer_create (RBSIZE * sizeof(midimsg));
+
jack_set_process_callback (client, process, 0);
port = jack_port_register (client, "input", JACK_DEFAULT_MIDI_TYPE, JackPortIsInput, 0);
@@ -160,6 +164,12 @@ main (int argc, char* argv[])
exit (EXIT_FAILURE);
}
+#ifndef WIN32
+ if (mlockall (MCL_CURRENT | MCL_FUTURE)) {
+ fprintf (stderr, "Warning: Can not lock memory.\n");
+ }
+#endif
+
r = jack_activate (client);
if (r != 0) {
fprintf (stderr, "Could not activate client.\n");
@@ -171,17 +181,44 @@ main (int argc, char* argv[])
signal(SIGINT, wearedone);
#endif
- /* run until interrupted */
+ pthread_mutex_lock (&msg_thread_lock);
+
+ uint64_t prev_event = 0;
while (keeprunning) {
- #ifdef WIN32
- Sleep(1000);
- #else
- sleep(1);
- #endif
- };
+ const int mqlen = jack_ringbuffer_read_space (rb) / sizeof(midimsg);
+ int i;
+ for (i=0; i < mqlen; ++i) {
+ size_t j;
+ midimsg m;
+ jack_ringbuffer_read(rb, (char*) &m, sizeof(midimsg));
+
+ switch(time_format) {
+ case 1:
+ printf ("%7"PRId64":", m.tme_rel + m.tme_mon);
+ break;
+ case 2:
+ printf ("%+6"PRId64":", m.tme_rel + m.tme_mon - prev_event);
+ break;
+ default:
+ printf ("%4d:", m.tme_rel);
+ break;
+ }
+ for (j = 0; j < m.size && j < sizeof(m.buffer); ++j) {
+ printf (" %02x", m.buffer[j]);
+ }
+
+ describe (&m);
+ printf("\n");
+ prev_event = m.tme_rel + m.tme_mon;
+ }
+ fflush (stdout);
+ pthread_cond_wait (&data_ready, &msg_thread_lock);
+ }
+ pthread_mutex_unlock (&msg_thread_lock);
jack_deactivate (client);
jack_client_close (client);
+ jack_ringbuffer_free (rb);
return 0;
}
--
1.7.10.4
1388494623.17276_0.ltw:2, <1388494607-1336-4-git-send-email-robin at gareus dot org>