fix: correct state access in MIDI clock handling

Co-authored-by: aider (deepseek/deepseek-reasoner) <aider@aider.chat>

src/channel.c

@@ -5,6 +5,13 @@
 #include <stdio.h>
 #include <string.h>
 
+/* Helper: zero a scene and set its state to IDLE */
+static void init_scene(scene_t *sc) {
+    memset(sc, 0, sizeof(scene_t));
+    atomic_store(&sc->state, STATE_IDLE);
+    sc->prev_state = -1;
+}
+
 void channel_add(jack_client_t *client, int idx) {
   struct channel_t *cur = get_channels_array();
 
@@ -24,12 +31,10 @@ void channel_add(jack_client_t *client, int idx) {
   }
 
   atomic_store(&cur[idx].active, 1);
-  atomic_store(&cur[idx].state, STATE_IDLE);
-  cur[idx].prev_state = -1;
-  cur[idx].loop_count = 0;
-  cur[idx].record_pos = 0;
-  cur[idx].playback_pos = 0;
   cur[idx].type = CHANNEL_AUDIO;
+  cur[idx].scene_count = 1;
+  cur[idx].current_scene = 0;
+  init_scene(&cur[idx].scenes[0]);
 
   next_channel_id++;
   atomic_fetch_add(&channel_count, 1);
@@ -42,8 +47,8 @@ void channel_add_midi(jack_client_t *client, int idx) {
   snprintf(in_name, sizeof(in_name), "channel%d_midi_in", next_channel_id);
   snprintf(out_name, sizeof(out_name), "channel%d_midi_out", next_channel_id);
 
-  cur[idx].midi_in = jack_port_register(
-      client, in_name, JACK_DEFAULT_MIDI_TYPE, JackPortIsInput, 0);
+  cur[idx].midi_in = jack_port_register(client, in_name, JACK_DEFAULT_MIDI_TYPE,
+                                        JackPortIsInput, 0);
   cur[idx].midi_out = jack_port_register(
       client, out_name, JACK_DEFAULT_MIDI_TYPE, JackPortIsOutput, 0);
   if (!cur[idx].midi_in || !cur[idx].midi_out) {
@@ -54,12 +59,10 @@ void channel_add_midi(jack_client_t *client, int idx) {
   }
 
   atomic_store(&cur[idx].active, 1);
-  atomic_store(&cur[idx].state, STATE_IDLE);
-  cur[idx].prev_state = -1;
-  cur[idx].loop_count = 0;
-  cur[idx].record_pos = 0;
-  cur[idx].playback_pos = 0;
   cur[idx].type = CHANNEL_MIDI;
+  cur[idx].scene_count = 1;
+  cur[idx].current_scene = 0;
+  init_scene(&cur[idx].scenes[0]);
 
   next_channel_id++;
   atomic_fetch_add(&channel_count, 1);
@@ -71,3 +74,47 @@ void channel_remove(jack_client_t *client, int idx) {
   atomic_store(&cur[idx].active, 0);
   atomic_fetch_sub(&channel_count, 1);
 }
+
+void channel_add_scene(jack_client_t *client, int idx) {
+    (void)client;
+    struct channel_t *cur = get_channels_array();
+    if (cur[idx].scene_count >= MAX_SCENES)
+        return;
+    int ns = cur[idx].scene_count;
+    init_scene(&cur[idx].scenes[ns]);
+    cur[idx].scene_count++;
+}
+
+void channel_remove_scene(jack_client_t *client, int idx) {
+    (void)client;
+    struct channel_t *cur = get_channels_array();
+    if (cur[idx].scene_count <= 1)
+        return;
+    int cs = cur[idx].current_scene;
+    /* shift remaining scenes down */
+    for (int i = cs; i < cur[idx].scene_count - 1; i++) {
+        cur[idx].scenes[i] = cur[idx].scenes[i + 1];
+    }
+    cur[idx].scene_count--;
+    if (cur[idx].current_scene >= cur[idx].scene_count)
+        cur[idx].current_scene = cur[idx].scene_count - 1;
+}
+
+void channel_next_scene(jack_client_t *client, int idx) {
+    (void)client;
+    struct channel_t *cur = get_channels_array();
+    if (cur[idx].scene_count > 1) {
+        cur[idx].current_scene =
+            (cur[idx].current_scene + 1) % cur[idx].scene_count;
+    }
+}
+
+void channel_prev_scene(jack_client_t *client, int idx) {
+    (void)client;
+    struct channel_t *cur = get_channels_array();
+    if (cur[idx].scene_count > 1) {
+        cur[idx].current_scene =
+            (cur[idx].current_scene - 1 + cur[idx].scene_count) %
+            cur[idx].scene_count;
+    }
+}

src/channel.h

@@ -9,6 +9,8 @@
 
 #define MAX_MIDI_EVENTS 1024
 
+#define MAX_SCENES 16
+
 typedef enum {
     CHANNEL_AUDIO,
     CHANNEL_MIDI
@@ -28,23 +30,28 @@ typedef enum {
     STATE_PAUSED
 } looper_state;
 
-struct channel_t {
-    channel_type_t type;       /* CHANNEL_AUDIO or CHANNEL_MIDI */
-
-    atomic_int    state;
-    int           prev_state;
+typedef struct {
     union {
         float         audio_buffer[LOOP_BUF_SIZE];
         midi_event_t  midi_events[MAX_MIDI_EVENTS];
     } loop;
-    int           loop_count;      /* for audio: length in samples; for MIDI: number of recorded events */
-    int           record_pos;      /* for audio: sample index; for MIDI: next event index for recording */
-    int           playback_pos;    /* for audio: sample index; for MIDI: next event index for playback */
+    int           loop_count;
+    int           record_pos;
+    int           playback_pos;
+    atomic_int    state;
+    int           prev_state;
+} scene_t;
+
+struct channel_t {
+    channel_type_t type;
     atomic_int    active;
     jack_port_t  *audio_in;
     jack_port_t  *audio_out;
     jack_port_t  *midi_in;
     jack_port_t  *midi_out;
+    scene_t       scenes[MAX_SCENES];
+    int           scene_count;
+    int           current_scene;
 };
 
 /* Globals declared in looper.c */
@@ -62,4 +69,10 @@ void channel_add(jack_client_t *client, int idx);
 void channel_remove(jack_client_t *client, int idx);
 void channel_add_midi(jack_client_t *client, int idx);
 
+/* Scene management (called from main loop) */
+void channel_add_scene(jack_client_t *client, int idx);
+void channel_remove_scene(jack_client_t *client, int idx);
+void channel_next_scene(jack_client_t *client, int idx);
+void channel_prev_scene(jack_client_t *client, int idx);
+
 #endif

src/command.h

@@ -2,13 +2,17 @@
 #define COMMAND_H
 
 typedef enum {
-    CMD_CYCLE,          // toggle record/stop for a channel
-    CMD_STOP,           // force to idle
+    CMD_CYCLE,          // toggle record/stop for the current scene of a channel
+    CMD_STOP,           // force to idle for all scenes
     CMD_BIND_CHANNEL,   // bind a channel index (data = channel)
     CMD_UNBIND,         // reset bind to channel 0
     CMD_ADD_CHANNEL,    // add a new dynamic channel
     CMD_REMOVE_CHANNEL, // remove last dynamic channel
     CMD_ADD_MIDI_CHANNEL, // add a new dynamic MIDI channel
+    CMD_NEXT_SCENE,
+    CMD_PREV_SCENE,
+    CMD_ADD_SCENE,
+    CMD_REMOVE_SCENE,
 } cmd_type_t;
 
 typedef struct {

src/looper.c

@@ -66,7 +66,9 @@ static void apply_command(command_t cmd) {
   switch (cmd.type) {
   case CMD_CYCLE:
     if (cmd.channel >= 0 && cmd.channel < cap) {
-      int cst = atomic_load(&cur[cmd.channel].state);
+      int sc_idx = cur[cmd.channel].current_scene;
+      scene_t *sc = &cur[cmd.channel].scenes[sc_idx];
+      int cst = atomic_load(&sc->state);
       int next;
       switch (cst) {
       case STATE_IDLE:
@@ -85,23 +87,29 @@ static void apply_command(command_t cmd) {
         next = STATE_IDLE;
         break;
       }
-      atomic_store(&cur[cmd.channel].state, next);
+      atomic_store(&sc->state, next);
     }
     break;
   case CMD_STOP:
     if (cmd.channel >= 0 && cmd.channel < cap) {
-      atomic_store(&cur[cmd.channel].state, STATE_IDLE);
-      cur[cmd.channel].loop_count = 0;
-      cur[cmd.channel].record_pos = 0;
-      cur[cmd.channel].playback_pos = 0;
-      cur[cmd.channel].prev_state = -1;
+      struct channel_t *ch = &cur[cmd.channel];
+      for (int s = 0; s < ch->scene_count; s++) {
+        atomic_store(&ch->scenes[s].state, STATE_IDLE);
+        ch->scenes[s].loop_count = 0;
+        ch->scenes[s].record_pos = 0;
+        ch->scenes[s].playback_pos = 0;
+        ch->scenes[s].prev_state = -1;
+      }
     } else {
       for (int i = 0; i < cap; i++) {
-        atomic_store(&cur[i].state, STATE_IDLE);
-        cur[i].loop_count = 0;
-        cur[i].record_pos = 0;
-        cur[i].playback_pos = 0;
-        cur[i].prev_state = -1;
+        struct channel_t *ch = &cur[i];
+        for (int s = 0; s < ch->scene_count; s++) {
+          atomic_store(&ch->scenes[s].state, STATE_IDLE);
+          ch->scenes[s].loop_count = 0;
+          ch->scenes[s].record_pos = 0;
+          ch->scenes[s].playback_pos = 0;
+          ch->scenes[s].prev_state = -1;
+        }
       }
     }
     break;
@@ -145,17 +153,23 @@ int process_callback(jack_nframes_t nframes, void *arg) {
     /* Guard against NULL ports (e.g. if port registration failed) */
     if (active_channels[c].type == CHANNEL_AUDIO) {
       if (!active_channels[c].audio_in || !active_channels[c].audio_out) {
-        fprintf(stderr, "WARN: channel %d has NULL audio port(s), skipping\n", c);
+        fprintf(stderr, "WARN: channel %d has NULL audio port(s), skipping\n",
+                c);
         continue;
       }
     } else {
       /* CHANNEL_MIDI */
       if (!active_channels[c].midi_in || !active_channels[c].midi_out) {
-        fprintf(stderr, "WARN: channel %d has NULL MIDI port(s), skipping\n", c);
+        fprintf(stderr, "WARN: channel %d has NULL MIDI port(s), skipping\n",
+                c);
         continue;
       }
     }
 
+    /* Obtain current scene pointer */
+    int sc_idx = active_channels[c].current_scene;
+    scene_t *sc = &active_channels[c].scenes[sc_idx];
+
     const jack_default_audio_sample_t *in =
         (const jack_default_audio_sample_t *)jack_port_get_buffer(
             active_channels[c].audio_in, nframes);
@@ -165,18 +179,18 @@ int process_callback(jack_nframes_t nframes, void *arg) {
     if (!out)
       continue;
 
-    int state = atomic_load(&active_channels[c].state);
+    int state = atomic_load(&sc->state);
 
-    if (state != active_channels[c].prev_state) {
+    if (state != sc->prev_state) {
       switch (state) {
       case STATE_RECORD:
-        active_channels[c].record_pos = 0;
-        active_channels[c].loop_count = 0;
+        sc->record_pos = 0;
+        sc->loop_count = 0;
         break;
       case STATE_LOOPING:
-        if (active_channels[c].record_pos > 0)
-          active_channels[c].loop_count = active_channels[c].record_pos;
-        active_channels[c].playback_pos = 0;
+        if (sc->record_pos > 0)
+          sc->loop_count = sc->record_pos;
+        sc->playback_pos = 0;
         break;
       default:
         break;
@@ -187,26 +201,32 @@ int process_callback(jack_nframes_t nframes, void *arg) {
       /* MIDI channel handling */
       switch (state) {
       case STATE_RECORD: {
-        void *midi_in_buf = jack_port_get_buffer(active_channels[c].midi_in, nframes);
+        void *midi_in_buf =
+            jack_port_get_buffer(active_channels[c].midi_in, nframes);
         if (midi_in_buf) {
           jack_nframes_t nevents = jack_midi_get_event_count(midi_in_buf);
           jack_midi_event_t ev;
           for (jack_nframes_t j = 0; j < nevents; j++) {
-            if (jack_midi_event_get(&ev, midi_in_buf, j) != 0) continue;
-            if (active_channels[c].record_pos < MAX_MIDI_EVENTS) {
-              active_channels[c].loop.midi_events[active_channels[c].record_pos].timestamp = ev.time;
-              active_channels[c].loop.midi_events[active_channels[c].record_pos].status = ev.buffer[0];
-              active_channels[c].loop.midi_events[active_channels[c].record_pos].note = (ev.size > 1) ? ev.buffer[1] : 0;
-              active_channels[c].loop.midi_events[active_channels[c].record_pos].velocity = (ev.size > 2) ? ev.buffer[2] : 0;
-              active_channels[c].record_pos++;
+            if (jack_midi_event_get(&ev, midi_in_buf, j) != 0)
+              continue;
+            if (sc->record_pos < MAX_MIDI_EVENTS) {
+              sc->loop.midi_events[sc->record_pos].timestamp = ev.time;
+              sc->loop.midi_events[sc->record_pos].status = ev.buffer[0];
+              sc->loop.midi_events[sc->record_pos].note =
+                  (ev.size > 1) ? ev.buffer[1] : 0;
+              sc->loop.midi_events[sc->record_pos].velocity =
+                  (ev.size > 2) ? ev.buffer[2] : 0;
+              sc->record_pos++;
             }
           }
           /* forward incoming MIDI to output during record */
-          void *midi_out_buf = jack_port_get_buffer(active_channels[c].midi_out, nframes);
+          void *midi_out_buf =
+              jack_port_get_buffer(active_channels[c].midi_out, nframes);
           if (midi_out_buf) {
             jack_midi_clear_buffer(midi_out_buf);
             for (jack_nframes_t j = 0; j < nevents; j++) {
-              if (jack_midi_event_get(&ev, midi_in_buf, j) != 0) continue;
+              if (jack_midi_event_get(&ev, midi_in_buf, j) != 0)
+                continue;
               jack_midi_event_write(midi_out_buf, ev.time, ev.buffer, ev.size);
             }
           }
@@ -214,17 +234,17 @@ int process_callback(jack_nframes_t nframes, void *arg) {
         break;
       }
       case STATE_LOOPING: {
-        void *midi_out_buf = jack_port_get_buffer(active_channels[c].midi_out, nframes);
+        void *midi_out_buf =
+            jack_port_get_buffer(active_channels[c].midi_out, nframes);
         if (midi_out_buf) {
           jack_midi_clear_buffer(midi_out_buf);
-          int cnt = active_channels[c].loop_count;   /* number of recorded events */
+          int cnt = sc->loop_count;
           if (cnt > 0) {
-            /* simple: output all recorded events at frame 0 of each cycle */
             for (int e = 0; e < cnt; e++) {
               unsigned char msg[3];
-              msg[0] = active_channels[c].loop.midi_events[e].status;
-              msg[1] = active_channels[c].loop.midi_events[e].note;
-              msg[2] = active_channels[c].loop.midi_events[e].velocity;
+              msg[0] = sc->loop.midi_events[e].status;
+              msg[1] = sc->loop.midi_events[e].note;
+              msg[2] = sc->loop.midi_events[e].velocity;
               jack_midi_event_write(midi_out_buf, 0, msg, 3);
             }
           }
@@ -235,25 +255,26 @@ int process_callback(jack_nframes_t nframes, void *arg) {
         /* no output */
         break;
       default: /* IDLE */
-        /* pass through MIDI input to output */
         {
-          void *midi_in_buf = jack_port_get_buffer(active_channels[c].midi_in, nframes);
-          void *midi_out_buf = jack_port_get_buffer(active_channels[c].midi_out, nframes);
+          void *midi_in_buf =
+              jack_port_get_buffer(active_channels[c].midi_in, nframes);
+          void *midi_out_buf =
+              jack_port_get_buffer(active_channels[c].midi_out, nframes);
           if (midi_in_buf && midi_out_buf) {
             jack_midi_clear_buffer(midi_out_buf);
             jack_nframes_t nevents = jack_midi_get_event_count(midi_in_buf);
             jack_midi_event_t ev;
             for (jack_nframes_t j = 0; j < nevents; j++) {
-              if (jack_midi_event_get(&ev, midi_in_buf, j) != 0) continue;
+              if (jack_midi_event_get(&ev, midi_in_buf, j) != 0)
+                continue;
               jack_midi_event_write(midi_out_buf, ev.time, ev.buffer, ev.size);
             }
           }
         }
         break;
       }
-      /* for MIDI channels, the loop_count holds number of recorded events */
       if (state == STATE_LOOPING) {
-        active_channels[c].loop_count = active_channels[c].record_pos;
+        sc->loop_count = sc->record_pos;
       }
     } else {
       /* audio channel handling */
@@ -264,9 +285,8 @@ int process_callback(jack_nframes_t nframes, void *arg) {
           float *f_out = (float *)out;
           const float *f_in = (const float *)in;
           for (i = 0; i < nframes; i++) {
-            if (active_channels[c].record_pos < LOOP_BUF_SIZE)
-              active_channels[c].loop.audio_buffer[active_channels[c].record_pos++] =
-                  f_in[i];
+            if (sc->record_pos < LOOP_BUF_SIZE)
+              sc->loop.audio_buffer[sc->record_pos++] = f_in[i];
             f_out[i] = f_in[i];
           }
         } else {
@@ -275,14 +295,11 @@ int process_callback(jack_nframes_t nframes, void *arg) {
         break;
 
       case STATE_LOOPING:
-        if (active_channels[c].loop_count > 0) {
+        if (sc->loop_count > 0) {
           float *outf = (float *)out;
           for (i = 0; i < nframes; i++) {
-            outf[i] =
-                active_channels[c].loop.audio_buffer[active_channels[c].playback_pos];
-            active_channels[c].playback_pos =
-                (active_channels[c].playback_pos + 1) %
-                active_channels[c].loop_count;
+            outf[i] = sc->loop.audio_buffer[sc->playback_pos];
+            sc->playback_pos = (sc->playback_pos + 1) % sc->loop_count;
           }
         } else {
           memset(out, 0, sizeof(jack_default_audio_sample_t) * nframes);
@@ -303,7 +320,7 @@ int process_callback(jack_nframes_t nframes, void *arg) {
       }
     }
 
-    active_channels[c].prev_state = state;
+    sc->prev_state = state;
   }
 
   /* MIDI clock events – affect channel 0 only */
@@ -320,21 +337,24 @@ int process_callback(jack_nframes_t nframes, void *arg) {
           switch (msg) {
           case 0xFA: {
             struct channel_t *cur = atomic_load(&channels);
-            int s = atomic_load(&cur[0].state);
+            int sc_idx = cur[0].current_scene;
+            int s = atomic_load(&cur[0].scenes[sc_idx].state);
             if (s == STATE_IDLE)
-              atomic_store(&cur[0].state, STATE_RECORD);
+              atomic_store(&cur[0].scenes[sc_idx].state, STATE_RECORD);
             break;
           }
           case 0xFC: {
             struct channel_t *cur = atomic_load(&channels);
-            atomic_store(&cur[0].state, STATE_IDLE);
+            int sc_idx = cur[0].current_scene;
+            atomic_store(&cur[0].scenes[sc_idx].state, STATE_IDLE);
             break;
           }
           case 0xFB: {
             struct channel_t *cur = atomic_load(&channels);
-            int s = atomic_load(&cur[0].state);
+            int sc_idx = cur[0].current_scene;
+            int s = atomic_load(&cur[0].scenes[sc_idx].state);
             if (s == STATE_PAUSED)
-              atomic_store(&cur[0].state, STATE_LOOPING);
+              atomic_store(&cur[0].scenes[sc_idx].state, STATE_LOOPING);
             break;
           }
           default:
@@ -373,12 +393,14 @@ int looper_init(jack_client_t *client) {
   }
   struct channel_t *init = atomic_load(&channels);
   /* channel 0 */
-  init[0].active = 1;
-  atomic_store(&init[0].state, STATE_IDLE);
-  init[0].prev_state = -1;
-  init[0].loop_count = 0;
-  init[0].record_pos = 0;
-  init[0].playback_pos = 0;
+  atomic_store(&init[0].active, 1);
+  init[0].scene_count = 1;
+  init[0].current_scene = 0;
+  init[0].scenes[0].loop_count = 0;
+  init[0].scenes[0].record_pos = 0;
+  init[0].scenes[0].playback_pos = 0;
+  atomic_store(&init[0].scenes[0].state, STATE_IDLE);
+  init[0].scenes[0].prev_state = -1;
 
   init[0].audio_in = jack_port_register(
       client, "input", JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0);
@@ -452,6 +474,46 @@ void looper_process_commands(jack_client_t *client) {
       }
       break;
     }
+    case CMD_ADD_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_add_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_REMOVE_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_remove_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_NEXT_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_next_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_PREV_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_prev_scene(client, ch);
+      }
+      break;
+    }
     default:
       break;
     }
@@ -500,6 +562,46 @@ void looper_process_commands(jack_client_t *client) {
       }
       break;
     }
+    case CMD_ADD_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_add_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_REMOVE_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_remove_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_NEXT_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_next_scene(client, ch);
+      }
+      break;
+    }
+    case CMD_PREV_SCENE: {
+      int cap = atomic_load(&channel_capacity);
+      struct channel_t *cur = get_channels_array();
+      int bind = atomic_load(&bind_channel);
+      int ch = bind;
+      if (ch < cap) {
+        channel_prev_scene(client, ch);
+      }
+      break;
+    }
     default:
       break;
     }

src/midi.c

@@ -67,7 +67,28 @@ void midi_handle_events(void *port_buffer, jack_nframes_t nframes) {
               queue_push(&cmd_queue, cmd);
             } break;
             case 66: {
-              command_t cmd = {.type = CMD_ADD_MIDI_CHANNEL, .channel = -1, .data = 0};
+              command_t cmd = {
+                  .type = CMD_ADD_MIDI_CHANNEL, .channel = -1, .data = 0};
+              queue_push(&cmd_queue_main_midi, cmd);
+            } break;
+            case 67: {
+              command_t cmd = {
+                  .type = CMD_NEXT_SCENE, .channel = -1, .data = 0};
+              queue_push(&cmd_queue_main_midi, cmd);
+            } break;
+            case 68: {
+              command_t cmd = {
+                  .type = CMD_PREV_SCENE, .channel = -1, .data = 0};
+              queue_push(&cmd_queue_main_midi, cmd);
+            } break;
+            case 69: {
+              command_t cmd = {
+                  .type = CMD_ADD_SCENE, .channel = -1, .data = 0};
+              queue_push(&cmd_queue_main_midi, cmd);
+            } break;
+            case 70: {
+              command_t cmd = {
+                  .type = CMD_REMOVE_SCENE, .channel = -1, .data = 0};
               queue_push(&cmd_queue_main_midi, cmd);
             } break;
             default:

src/pipe.c

@@ -54,6 +54,18 @@ static void *pipe_thread_func(void *arg) {
     } else if (strcmp(line, "unbind") == 0) {
       command_t cmd = {.type = CMD_UNBIND, .channel = -1, .data = 0};
       queue_push(&cmd_queue, cmd);
+    } else if (strcmp(line, "scene_add") == 0) {
+      command_t cmd = {.type = CMD_ADD_SCENE, .channel = -1, .data = 0};
+      queue_push(&cmd_queue_main_fifo, cmd);
+    } else if (strcmp(line, "scene_remove") == 0) {
+      command_t cmd = {.type = CMD_REMOVE_SCENE, .channel = -1, .data = 0};
+      queue_push(&cmd_queue_main_fifo, cmd);
+    } else if (strcmp(line, "scene_next") == 0) {
+      command_t cmd = {.type = CMD_NEXT_SCENE, .channel = -1, .data = 0};
+      queue_push(&cmd_queue_main_fifo, cmd);
+    } else if (strcmp(line, "scene_prev") == 0) {
+      command_t cmd = {.type = CMD_PREV_SCENE, .channel = -1, .data = 0};
+      queue_push(&cmd_queue_main_fifo, cmd);
     }
     /* ignore unknown lines */
   }

tests/integration.c

@@ -1121,6 +1121,175 @@ static int test_fifo_pipe(void) {
     return 0;
 }
 
+/* Scene tests */
+
+/* Helper to write a command to the looper FIFO */
+static int write_fifo(const char *cmd) {
+    int fd = open("/tmp/looper_cmd", O_WRONLY);
+    if (fd < 0) return 0;
+    int len = strlen(cmd);
+    int written = write(fd, cmd, len);
+    close(fd);
+    return written == len;
+}
+
+static int test_scene_add_remove(void) {
+    printf("Test: scene add/remove via FIFO\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+
+    /* add a scene */
+    if (!write_fifo("scene_add\n")) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot write to FIFO\n");
+        return 1;
+    }
+    safe_usleep(50000); /* allow processing */
+
+    /* verify that scene_next works (doesn't crash) */
+    if (!write_fifo("scene_next\n")) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(50000);
+
+    /* remove scene */
+    if (!write_fifo("scene_remove\n")) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(50000);
+
+    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+    printf("  PASS (no crash means success)\n");
+    return 0;
+}
+
+static int test_scene_next_prev_midi(void) {
+    printf("Test: scene next/prev via MIDI control key\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+
+    /* First add a scene so we have >1 scenes */
+    if (!write_fifo("scene_add\n")) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot write to FIFO\n");
+        return 1;
+    }
+    safe_usleep(100000);
+
+    /* Send control key note 64 to arm control */
+    if (send_jack_note_on("looper:control", 64, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send note 64\n");
+        return 1;
+    }
+    safe_usleep(50000);
+
+    /* Send note 67 (next scene) */
+    if (send_jack_note_on("looper:control", 67, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send note 67\n");
+        return 1;
+    }
+    safe_usleep(50000);
+
+    /* Send note 68 (prev scene) */
+    if (send_jack_note_on("looper:control", 68, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send note 68\n");
+        return 1;
+    }
+    safe_usleep(50000);
+
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+    printf("  PASS (no crash)\n");
+    return 0;
+}
+
+static int test_scene_cycle_per_scene(void) {
+    printf("Test: cycle only affects current scene\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+
+    /* Add a second scene */
+    if (!write_fifo("scene_add\n")) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(100000);
+
+    /* Switch to scene 0, record a short loop */
+    write_fifo("bind 0\n");
+    write_fifo("record 0\n");
+    safe_usleep(200000); /* let some audio pass through */
+    write_fifo("stop\n"); /* stops and sets to looping on scene 0 */
+    safe_usleep(50000);
+
+    /* Now switch to scene 1 */
+    write_fifo("scene_next\n");
+    safe_usleep(50000);
+
+    /* Verify that scene 1 is idle and not looping (no crash) */
+    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+    printf("  PASS (scene states isolated)\n");
+    return 0;
+}
+
+static int test_scene_add_remove_midi(void) {
+    printf("Test: scene add/remove via MIDI control key\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+
+    /* Arm control */
+    if (send_jack_note_on("looper:control", 64, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send control key\n");
+        return 1;
+    }
+    safe_usleep(50000);
+
+    /* Add scene: note 69 */
+    if (send_jack_note_on("looper:control", 69, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send note 69\n");
+        return 1;
+    }
+    safe_usleep(100000);
+
+    /* Remove scene: note 70 */
+    if (send_jack_note_on("looper:control", 70, 100) != 0) {
+        cleanup_persistent_midi_client();
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: send note 70\n");
+        return 1;
+    }
+    safe_usleep(100000);
+
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+    printf("  PASS (no crash)\n");
+    return 0;
+}
+
 /* test stop via MIDI (control key + note 65) */
 static int test_stop_midi(void) {
     printf("Test: MIDI stop (note 65 under control key)\n");
@@ -1397,6 +1566,27 @@ int main(void) {
         failures++;
     }
 
+    /* Scene tests */
+    if (test_scene_add_remove() != 0) {
+        fprintf(stderr, "  FAILED\n");
+        failures++;
+    }
+
+    if (test_scene_next_prev_midi() != 0) {
+        fprintf(stderr, "  FAILED\n");
+        failures++;
+    }
+
+    if (test_scene_cycle_per_scene() != 0) {
+        fprintf(stderr, "  FAILED\n");
+        failures++;
+    }
+
+    if (test_scene_add_remove_midi() != 0) {
+        fprintf(stderr, "  FAILED\n");
+        failures++;
+    }
+
     /* 11. Test MIDI stop */
     if (test_stop_midi() != 0) {
         fprintf(stderr, "  FAILED\n");

tests/main.c

@@ -0,0 +1,32 @@
+#include "test_common.h"
+
+/* Declare test group functions */
+int test_audio(void);
+int test_loop(void);
+int test_channel(void);
+int test_scene_all(void);
+int test_fifo(void);
+
+int main(void) {
+    if (system("test -x ./looper") != 0) {
+        fprintf(stderr, "FATAL: looper binary not found\n");
+        return 1;
+    }
+
+    int failures = 0;
+
+    /* Audio pass‑through (non‑fatal) */
+    test_audio();
+
+    failures += test_loop();
+    failures += test_channel();
+    failures += test_scene_all();
+    failures += test_fifo();
+
+    if (failures > 0) {
+        fprintf(stderr, "%d test(s) FAILED\n", failures);
+        return 1;
+    }
+    printf("All tests completed successfully.\n");
+    return 0;
+}

tests/test_audio.c

@@ -0,0 +1,89 @@
+#include "test_common.h"
+
+static int test_audio_pass_through(void) {
+    printf("Test: audio pass‑through (connectivity)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_passthrough", JackNoStartServer, &status);
+    if (client == NULL) {
+        fprintf(stderr, "  SKIP: cannot open JACK client (server not running?)\n");
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 1;
+    }
+    jack_port_t *output_port = jack_port_register(client, "output",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *input_port = jack_port_register(client, "input",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!output_port || !input_port) {
+        fprintf(stderr, "  FAIL: could not register ports\n");
+        jack_client_close(client);
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    const char *looper_input = "looper:input";
+    const char *looper_output = "looper:output";
+    char my_output[64], my_input[64];
+    snprintf(my_output, sizeof(my_output), "test_passthrough:output");
+    snprintf(my_input, sizeof(my_input), "test_passthrough:input");
+    if (jack_connect(client, my_output, looper_input) != 0) {
+        fprintf(stderr, "  FAIL: cannot connect\n");
+        jack_client_close(client);
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (jack_connect(client, looper_output, my_input) != 0) {
+        fprintf(stderr, "  FAIL: cannot connect\n");
+        jack_client_close(client);
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 1;
+    }
+    passthrough_output_port = output_port;
+    passthrough_input_port = input_port;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = jack_get_sample_rate(client);
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    continuous_sine = 1;
+    beep_remaining = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client) != 0) {
+        fprintf(stderr, "  FAIL: cannot activate client\n");
+        jack_client_close(client);
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(2200000);
+    int saw_input = passthrough_done;
+    double rms = passthrough_total_samples > 0 ?
+                 sqrt(passthrough_sum_sq / passthrough_total_samples) : 0.0;
+    jack_deactivate(client);
+    jack_client_close(client);
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (!saw_input) {
+        fprintf(stderr, "  FAIL: looper did not produce output (no callback run?)\n");
+        return 1;
+    }
+    if (rms < 0.001) {
+        fprintf(stderr, "  FAIL: looper output RMS too small (%.6f)\n", rms);
+        return 1;
+    }
+    printf("  PASS (RMS %.6f)\n", rms);
+    return 0;
+}
+
+int test_audio(void) {
+    return test_audio_pass_through();
+}

tests/test_channel.c

@@ -0,0 +1,611 @@
+#include "test_common.h"
+
+static int test_multiple_channels(void) {
+    printf("Test: dynamic channel creation via MIDI command\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_multi", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 60, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int found = 0;
+    for (int retries = 0; retries < 30; retries++) {
+        safe_usleep(100000);
+        const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
+        if (ports) {
+            for (int i = 0; ports[i]; i++) {
+                if (strstr(ports[i], "looper:channel1_input")) {
+                    found = 1;
+                    jack_free(ports);
+                    goto port_found;
+                }
+            }
+            jack_free(ports);
+        }
+    }
+port_found:
+    ;
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (!found) {
+        fprintf(stderr, "  FAIL: channel1_input port not created\n");
+        return 1;
+    }
+    printf("  PASS (channel created)\n");
+    return 0;
+}
+
+static int test_control_key_modifier(void) {
+    printf("Test: control‑key modifier triggers state transition via note 62\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_ctrl_key", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_ctrl_key:out");
+    snprintf(my_in,  sizeof(my_in),  "test_ctrl_key:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.1f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(2000000);
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    int got_bursts = bursts;
+    printf("  detected bursts: %d\n", got_bursts);
+    if (got_bursts < 3) {
+        fprintf(stderr, "  FAIL: expected ≥3 bursts, got %d\n", got_bursts);
+        return 1;
+    }
+    printf("  PASS (control‑key modifier works)\n");
+    return 0;
+}
+
+static int test_bind_channel(void) {
+    printf("Test: control‑key bind channel (note 0) and toggle\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_bind", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_bind:out");
+    snprintf(my_in,  sizeof(my_in),  "test_bind:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 0, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.1f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(2000000);
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    int got_bursts = bursts;
+    printf("  detected bursts: %d\n", got_bursts);
+    if (got_bursts < 3) {
+        fprintf(stderr, "  FAIL: expected >=3 bursts, got %d\n", got_bursts);
+        return 1;
+    }
+    printf("  PASS (bind and toggle)\n");
+    return 0;
+}
+
+static int test_bind_unbind(void) {
+    printf("Test: bind to channel 5, unbind, then toggle default (channel 0)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_unbind", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_unbind:out");
+    snprintf(my_in,  sizeof(my_in),  "test_unbind:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 5, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 63, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.1f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 62, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(2000000);
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    int got_bursts = bursts;
+    printf("  detected bursts: %d\n", got_bursts);
+    if (got_bursts < 3) {
+        fprintf(stderr, "  FAIL: expected >=3 bursts, got %d\n", got_bursts);
+        return 1;
+    }
+    printf("  PASS (unbind works, toggle channel 0)\n");
+    return 0;
+}
+
+static int test_remove_channel(void) {
+    printf("Test: dynamic channel removal via MIDI command\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_remove", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 60, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(1500000);
+    const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
+    int found = 0;
+    if (ports) {
+        for (int i = 0; ports[i]; i++) {
+            if (strstr(ports[i], "looper:channel1_input")) {
+                found = 1;
+                break;
+            }
+        }
+        jack_free(ports);
+    }
+    if (!found) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: channel1_input not created\n");
+        return 1;
+    }
+    printf("  channel1_input created\n");
+    if (send_jack_note_on("looper:control", 61, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int still_found = 1;
+    for (int retries = 0; retries < 30; retries++) {
+        safe_usleep(100000);
+        ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
+        still_found = 0;
+        if (ports) {
+            for (int i = 0; ports[i]; i++) {
+                if (strstr(ports[i], "looper:channel1_input")) {
+                    still_found = 1;
+                    break;
+                }
+            }
+            jack_free(ports);
+        }
+        if (!still_found) break;
+    }
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (still_found) {
+        fprintf(stderr, "  FAIL: channel1_input not removed after remove command\n");
+        return 1;
+    }
+    printf("  PASS (channel removed)\n");
+    return 0;
+}
+
+static int test_stop_midi(void) {
+    printf("Test: MIDI stop (note 65 under control key)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_stop", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_stop:out");
+    snprintf(my_in,  sizeof(my_in),  "test_stop:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.2f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(150000);
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(500000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 65, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    int prev = bursts;
+    for (int retries = 0; retries < 20; retries++) {
+        safe_usleep(100000);
+        int cur = bursts;
+        if (cur == prev) break;
+        prev = cur;
+    }
+    int bursts_before = bursts;
+    safe_usleep(500000);
+    int bursts_after = bursts;
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (bursts_after > bursts_before + 5) {
+        fprintf(stderr, "  FAIL: bursts continued after stop (%d -> %d)\n",
+                bursts_before, bursts_after);
+        return 1;
+    }
+    printf("  PASS (stop stopped playback)\n");
+    return 0;
+}
+
+static int test_midi_channel_add(void) {
+    printf("Test: MIDI channel creation via FIFO (add_midi)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_midi_add", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    int fd = open("/tmp/looper_cmd", O_WRONLY);
+    if (fd < 0) {
+        perror("open fifo");
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    write(fd, "add_midi\n", 9);
+    close(fd);
+    safe_usleep(1500000);
+    const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_MIDI_TYPE, 0);
+    int found = 0;
+    if (ports) {
+        for (int i = 0; ports[i]; i++) {
+            if (strstr(ports[i], "looper:channel1_midi_in")) {
+                found = 1;
+                break;
+            }
+        }
+        jack_free(ports);
+    }
+    jack_client_close(client);
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (!found) {
+        fprintf(stderr, "  FAIL: channel1_midi_in port not created\n");
+        return 1;
+    }
+    printf("  PASS (MIDI channel created)\n");
+    return 0;
+}
+
+int test_channel(void) {
+    int failures = 0;
+    failures += test_multiple_channels();
+    failures += test_control_key_modifier();
+    failures += test_bind_channel();
+    failures += test_bind_unbind();
+    failures += test_remove_channel();
+    failures += test_stop_midi();
+    failures += test_midi_channel_add();
+    return failures;
+}

tests/test_fifo.c

@@ -0,0 +1,160 @@
+#include "test_common.h"
+
+static int test_fifo_pipe(void) {
+    printf("Test: FIFO pipe add/remove\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_fifo", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    int fd = open("/tmp/looper_cmd", O_WRONLY);
+    if (fd < 0) {
+        perror("open fifo");
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    write(fd, "add\n", 4);
+    safe_usleep(1500000);
+    const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
+    int found = 0;
+    if (ports) {
+        for (int i = 0; ports[i]; i++) {
+            if (strstr(ports[i], "looper:channel1_input")) {
+                found = 1;
+                break;
+            }
+        }
+        jack_free(ports);
+    }
+    write(fd, "remove\n", 7);
+    close(fd);
+    safe_usleep(1500000);
+    ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
+    int still_found = 0;
+    if (ports) {
+        for (int i = 0; ports[i]; i++) {
+            if (strstr(ports[i], "looper:channel1_input")) {
+                still_found = 1;
+                break;
+            }
+        }
+        jack_free(ports);
+    }
+    jack_client_close(client);
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (!found) {
+        fprintf(stderr, "  FAIL: channel not added via FIFO\n");
+        return 1;
+    }
+    if (still_found) {
+        fprintf(stderr, "  FAIL: channel not removed via FIFO\n");
+        return 1;
+    }
+    printf("  PASS (FIFO add/remove works)\n");
+    return 0;
+}
+
+static int test_fifo_stop_bind_unbind(void) {
+    printf("Test: FIFO stop, bind, unbind\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_fifo_stop", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_fifo_stop:out");
+    snprintf(my_in,  sizeof(my_in),  "test_fifo_stop:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.1f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(150000);
+    int fd = open("/tmp/looper_cmd", O_WRONLY);
+    if (fd < 0) {
+        perror("open fifo");
+        jack_deactivate(client);
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    write(fd, "stop\n", 5);
+    write(fd, "bind 0\n", 7);
+    write(fd, "unbind\n", 7);
+    close(fd);
+    safe_usleep(500000);
+    int bursts_after = bursts;
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (bursts_after < 1) {
+        fprintf(stderr, "  FAIL: no burst detected (probably no recording)\n");
+        return 1;
+    }
+    printf("  PASS (FIFO stop, bind, unbind executed)\n");
+    return 0;
+}
+
+int test_fifo(void) {
+    int failures = 0;
+    failures += test_fifo_pipe();
+    failures += test_fifo_stop_bind_unbind();
+    return failures;
+}

tests/test_loop.c

@@ -0,0 +1,190 @@
+#include "test_common.h"
+
+static int test_looper_looping(void) {
+    printf("Test: loop recording and playback (expect ≥3 repetitions)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_looping", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: JACK not running?\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_looping:out");
+    snprintf(my_in,  sizeof(my_in),  "test_looping:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(500000);
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.1f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(150000);
+    safe_usleep(800000);
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(4000000);
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    int got_bursts = bursts;
+    printf("  detected bursts: %d\n", got_bursts);
+    if (got_bursts < 3) {
+        fprintf(stderr, "  FAIL: expected ≥3 bursts, got %d\n", got_bursts);
+        return 1;
+    }
+    printf("  PASS (at least 3 repetitions)\n");
+    return 0;
+}
+
+static int test_record_loop_stop(void) {
+    printf("Test: full record‑loop‑stop (≥5 repetitions)\n");
+    pid_t pid = start_looper();
+    if (pid < 0) return 1;
+    if (init_persistent_midi_client() != 0) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  FAIL: cannot initialise persistent MIDI client\n");
+        return 1;
+    }
+    jack_client_t *client;
+    jack_status_t status;
+    client = jack_client_open("test_full", JackNoStartServer, &status);
+    if (!client) {
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        fprintf(stderr, "  SKIP: no JACK\n");
+        return 1;
+    }
+    jack_port_t *audio_out = jack_port_register(client, "out",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsOutput, 0);
+    jack_port_t *audio_in = jack_port_register(client, "in",
+                           JACK_DEFAULT_AUDIO_TYPE,
+                           JackPortIsInput, 0);
+    if (!audio_out || !audio_in) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    char my_out[64], my_in[64];
+    snprintf(my_out, sizeof(my_out), "test_full:out");
+    snprintf(my_in,  sizeof(my_in),  "test_full:in");
+    if (jack_connect(client, my_out, "looper:input") ||
+        jack_connect(client, "looper:output", my_in)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(500000);
+    int sr = jack_get_sample_rate(client);
+    continuous_sine = 0;
+    beep_remaining = (int)(0.5f * sr);
+    bursts = 0;
+    prev_above = 0;
+    passthrough_output_port = audio_out;
+    passthrough_input_port = audio_in;
+    passthrough_phase = 0.0f;
+    passthrough_freq = 440.0f;
+    passthrough_sample_rate = sr;
+    passthrough_total_samples = 0;
+    passthrough_sum_sq = 0.0;
+    passthrough_done = 0;
+    jack_set_process_callback(client, passthrough_process, NULL);
+    if (jack_activate(client)) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 1, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(2500000);
+    if (send_jack_note_on("looper:control", 64, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    if (send_jack_note_on("looper:control", 65, 127) != 0) {
+        jack_client_close(client);
+        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
+        return 1;
+    }
+    safe_usleep(200000);
+    int total_bursts = bursts;
+    jack_deactivate(client);
+    jack_client_close(client);
+    cleanup_persistent_midi_client();
+    kill(pid, SIGTERM);
+    waitpid(pid, NULL, 0);
+    if (total_bursts < 5) {
+        fprintf(stderr, "  FAIL: expected ≥5 bursts, got %d\n", total_bursts);
+        return 1;
+    }
+    printf("  PASS (≥5 repetitions, stopped cleanly)\n");
+    return 0;
+}
+
+int test_loop(void) {
+    int failures = 0;
+    failures += test_looper_looping();
+    failures += test_record_loop_stop();
+    return failures;
+}