1 files changed, 127 insertions, 0 deletions
diff --git a/soundout/jackout.c b/soundout/jackout.c
new file mode 100644
index 0000000..54e7f16
--- /dev/null
+++ b/soundout/jackout.c
@@ -0,0 +1,127 @@
+#include "jackout.h"
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <jack/jack.h>
+#include <soxr.h>
+
+typedef jack_default_audio_sample_t sample_t;
+
+enum {
+  RFRAMES = 1024,
+  JFRAMES = 2048,
+};
+
+struct jackout_state {
+  struct sound_state ss;
+  sound_callback cbfunc;
+  void *userptr;
+  jack_client_t *jc;
+  jack_port_t *jp[2];
+  soxr_t soxr;
+  bool paused;
+  int16_t rbuf[RFRAMES*2];
+  float jbuf[JFRAMES*2];
+};
+
+static size_t soxr_cb(void *ptr, soxr_in_t *data, size_t nframes) {
+  struct jackout_state *js = ptr;
+  if (nframes > RFRAMES) nframes = RFRAMES;
+  for (size_t i = 0; i < RFRAMES*2; i++) {
+    js->rbuf[i] = 0;
+  }
+  js->cbfunc(js->userptr, js->rbuf, nframes);
+  *data = js->rbuf;
+  return nframes;
+}
+
+static int jack_cb(jack_nframes_t nframes, void *arg) {
+  struct jackout_state *js = arg;
+  sample_t *out[2];
+  for (int i = 0; i < 2; i++) out[i] = jack_port_get_buffer(js->jp[i], nframes);
+  jack_nframes_t outi = 0;
+  while (nframes) {
+    jack_nframes_t pframes = nframes < JFRAMES ? nframes : JFRAMES;
+    pframes = soxr_output(js->soxr, js->jbuf, pframes);
+    for (jack_nframes_t j = 0; j < pframes; j++) {
+      out[0][outi] = js->jbuf[j*2+0];
+      out[1][outi] = js->jbuf[j*2+1];
+      outi++;
+    }
+    nframes -= pframes;
+  }
+  return 0;
+}
+
+static void jackout_pause(struct sound_state *ss, int pause, int flush) {
+  struct jackout_state *js = (struct jackout_state *)ss;
+  // TODO
+  if (js->paused && !pause) {
+    if (flush) {
+      soxr_clear(js->soxr);
+      soxr_set_input_fn(js->soxr, soxr_cb, js, RFRAMES);
+    }
+    jack_activate(js->jc);
+    jack_connect(js->jc, jack_port_name(js->jp[0]), "system:playback_1");
+    jack_connect(js->jc, jack_port_name(js->jp[1]), "system:playback_2");
+  } else if (!js->paused && pause) {
+    jack_deactivate(js->jc);
+  }
+  js->paused = pause;
+}
+
+static void jackout_free(struct sound_state *ss) {
+  struct jackout_state *js = (struct jackout_state *)ss;
+  if (js) {
+    if (js->jc) {
+      for (int i = 0; i < 2; i++) {
+        if (js->jp[i]) jack_port_unregister(js->jc, js->jp[i]);
+      }
+      jack_client_close(js->jc);
+    }
+    if (js->soxr) soxr_delete(js->soxr);
+    free(js);
+  }
+}
+
+struct sound_state *jackout_init(
+  const char *clientname, unsigned srate,
+  sound_callback cbfunc, void *userptr) {
+  struct jackout_state *js = malloc(sizeof(*js));
+  if (!js) goto err;
+  *js = (struct jackout_state){
+    .ss = {
+      .pause = jackout_pause,
+      .free = jackout_free,
+      .apiname = "JACK Audio",
+    },
+    .cbfunc = cbfunc,
+    .userptr = userptr,
+    .paused = true,
+  };
+  js->jc = jack_client_open(clientname, 0, 0);
+  if (!js->jc) goto err;
+  for (int i = 0; i < 2; i++) {
+    js->jp[i] = jack_port_register(
+        js->jc, i ? "right" : "left", JACK_DEFAULT_AUDIO_TYPE,
+        JackPortIsOutput | JackPortIsTerminal, 0);
+    if (!js->jp[i]) goto err;
+  }
+  soxr_io_spec_t iospec = {
+    .itype = SOXR_INT16_I,
+    .otype = SOXR_FLOAT32_I,
+    .scale = 1.0,
+  };
+  js->soxr = soxr_create(
+      srate, jack_get_sample_rate(js->jc),
+      2, 0, &iospec, 0, 0
+  );
+  if (!js->soxr) goto err;
+  soxr_set_input_fn(js->soxr, soxr_cb, js, RFRAMES);
+  if (jack_set_process_callback(js->jc, jack_cb, js)) goto err;
+
+  return &js->ss;
+err:
+  jackout_free(&js->ss);
+  return 0;
+}