Allocate message buffers with the necessary size during setup

Remove static limits and instead allocate large enough buffers for any message
sent by the plugin.  These buffers only need to hold one message at a time, so
they can't be any larger than the largest port buffer (since the plugin
couldn't possibly write anything larger).

Also replaces some crude hammering on realloc() with reuse of one of these
known-large-enough buffers.

1 files changed, 18 insertions, 32 deletions

diff --git a/src/jalv.c b/src/jalv.c
index 6d688ec..f12db19 100644
--- a/src/jalv.c
+++ b/src/jalv.c
@@ -74,10 +74,6 @@
 #  define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
 #endif
 
-#ifndef MSG_BUFFER_SIZE
-#  define MSG_BUFFER_SIZE 1024
-#endif
-
 /**
    Size factor for UI ring buffers.
 
@@ -239,6 +235,7 @@ create_port(Jalv* jalv, uint32_t port_index, float default_value)
     port->buf_size = lilv_node_as_int(min_size);
     jalv->opts.ring_size =
       MAX(jalv->opts.ring_size, port->buf_size * N_BUFFER_CYCLES);
+    jalv->msg_buf_size = MAX(jalv->msg_buf_size, port->buf_size);
   }
   lilv_node_free(min_size);
 
@@ -463,8 +460,7 @@ jalv_set_control(Jalv*            jalv,
     // Copy forge since it is used by process thread
     LV2_Atom_Forge       forge = jalv->forge;
     LV2_Atom_Forge_Frame frame;
-    uint8_t              buf[MSG_BUFFER_SIZE];
-    lv2_atom_forge_set_buffer(&forge, buf, sizeof(buf));
+    lv2_atom_forge_set_buffer(&forge, jalv->ui_msg, jalv->msg_buf_size);
 
     lv2_atom_forge_object(&forge, &frame, 0, jalv->urids.patch_Set);
     lv2_atom_forge_key(&forge, jalv->urids.patch_property);
@@ -585,15 +581,8 @@ jalv_apply_ui_events(Jalv* jalv, uint32_t nframes)
       break;
     }
 
-    struct {
-      union {
-        LV2_Atom atom;
-        float    control;
-      } head;
-      uint8_t body[MSG_BUFFER_SIZE];
-    } buffer;
-
-    if (zix_ring_read(jalv->ui_to_plugin, &buffer, ev.size) != ev.size) {
+    void* const body = jalv->audio_msg;
+    if (zix_ring_read(jalv->ui_to_plugin, body, ev.size) != ev.size) {
       jalv_log(JALV_LOG_ERR, "Failed to read from UI ring buffer\n");
       break;
     }
@@ -602,10 +591,10 @@ jalv_apply_ui_events(Jalv* jalv, uint32_t nframes)
     struct Port* const port = &jalv->ports[ev.index];
     if (ev.protocol == 0) {
       assert(ev.size == sizeof(float));
-      port->control = buffer.head.control;
+      port->control = *(const float*)body;
     } else if (ev.protocol == jalv->urids.atom_eventTransfer) {
       LV2_Evbuf_Iterator    e    = lv2_evbuf_end(port->evbuf);
-      const LV2_Atom* const atom = &buffer.head.atom;
+      const LV2_Atom* const atom = (const LV2_Atom*)body;
       lv2_evbuf_write(
         &e, nframes, 0, atom->type, atom->size, LV2_ATOM_BODY_CONST(atom));
     } else {
@@ -630,8 +619,8 @@ jalv_init_ui(Jalv* jalv)
     // Send patch:Get message for initial parameters/etc
     LV2_Atom_Forge       forge = jalv->forge;
     LV2_Atom_Forge_Frame frame;
-    uint8_t              buf[MSG_BUFFER_SIZE];
-    lv2_atom_forge_set_buffer(&forge, buf, sizeof(buf));
+    uint64_t             buf[4U] = {0U, 0U, 0U, 0U};
+    lv2_atom_forge_set_buffer(&forge, (uint8_t*)buf, sizeof(buf));
     lv2_atom_forge_object(&forge, &frame, 0, jalv->urids.patch_Get);
 
     const LV2_Atom* atom = lv2_atom_forge_deref(&forge, frame.ref);
@@ -711,25 +700,18 @@ jalv_update(Jalv* jalv)
     // Read event header to get the size
     zix_ring_read(jalv->plugin_to_ui, &ev, sizeof(ev));
 
-    // Resize read buffer if necessary
-    void* const buf = realloc(jalv->ui_event_buf, ev.size);
-    if (!buf) {
-      return 12;
-    }
-
-    jalv->ui_event_buf = buf;
-
     // Read event body
-    zix_ring_read(jalv->plugin_to_ui, buf, ev.size);
+    void* const body = jalv->ui_msg;
+    zix_ring_read(jalv->plugin_to_ui, body, ev.size);
 
     if (ev.protocol == jalv->urids.atom_eventTransfer) {
-      jalv_dump_atom(jalv, stdout, "Plugin => UI", (const LV2_Atom*)buf, 35);
+      jalv_dump_atom(jalv, stdout, "Plugin => UI", (const LV2_Atom*)body, 35);
     }
 
-    jalv_frontend_port_event(jalv, ev.index, ev.size, ev.protocol, buf);
+    jalv_frontend_port_event(jalv, ev.index, ev.size, ev.protocol, body);
 
     if (ev.protocol == 0 && jalv->opts.print_controls) {
-      jalv_print_control(jalv, &jalv->ports[ev.index], *(float*)buf);
+      jalv_print_control(jalv, &jalv->ports[ev.index], *(float*)body);
     }
   }
 
@@ -1100,6 +1082,7 @@ jalv_open(Jalv* const jalv, int* argc, char*** argv)
   jalv->symap         = symap_new();
   jalv->block_length  = 4096U;
   jalv->midi_buf_size = 1024U;
+  jalv->msg_buf_size  = 1024U;
   jalv->play_state    = JALV_PAUSED;
   jalv->bpm           = 120.0f;
   jalv->control_in    = (uint32_t)-1;
@@ -1263,6 +1246,8 @@ jalv_open(Jalv* const jalv, int* argc, char*** argv)
   jalv_init_options(jalv);
 
   // Create Plugin <=> UI communication buffers
+  jalv->audio_msg    = zix_aligned_alloc(NULL, 8U, jalv->msg_buf_size);
+  jalv->ui_msg       = zix_aligned_alloc(NULL, 8U, jalv->msg_buf_size);
   jalv->ui_to_plugin = zix_ring_new(NULL, jalv->opts.ring_size);
   jalv->plugin_to_ui = zix_ring_new(NULL, jalv->opts.ring_size);
   zix_ring_mlock(jalv->ui_to_plugin);
@@ -1404,6 +1389,8 @@ jalv_close(Jalv* const jalv)
   free(jalv->ports);
   zix_ring_free(jalv->ui_to_plugin);
   zix_ring_free(jalv->plugin_to_ui);
+  zix_free(NULL, jalv->ui_msg);
+  zix_free(NULL, jalv->audio_msg);
   for (LilvNode** n = (LilvNode**)&jalv->nodes; *n; ++n) {
     lilv_node_free(*n);
   }
@@ -1445,7 +1432,6 @@ jalv_close(Jalv* const jalv)
   }
 
   zix_free(NULL, jalv->temp_dir);
-  free(jalv->ui_event_buf);
   free(jalv->feature_list);
 
   free(jalv->opts.name);