ctrl: break debug string events apart if needed; enforce size cap on serialized ctrl events

src/ctrl/ctrl_core.c

@@ -418,11 +418,11 @@ ctrl_event_list_concat_in_place(CTRL_EventList *dst, CTRL_EventList *to_push)
 //- rjf: serialization
 
 internal String8
-ctrl_serialized_string_from_event(Arena *arena, CTRL_Event *event)
+ctrl_serialized_string_from_event(Arena *arena, CTRL_Event *event, U64 max)
 {
   Temp scratch = scratch_begin(&arena, 1);
   String8List srl = {0};
-  str8_serial_begin(scratch.arena, &srl);;
+  str8_serial_begin(scratch.arena, &srl);
   {
     str8_serial_push_struct(scratch.arena, &srl, &event->kind);
     str8_serial_push_struct(scratch.arena, &srl, &event->cause);
@@ -440,8 +440,10 @@ ctrl_serialized_string_from_event(Arena *arena, CTRL_Event *event)
     str8_serial_push_struct(scratch.arena, &srl, &event->tls_root);
     str8_serial_push_struct(scratch.arena, &srl, &event->timestamp);
     str8_serial_push_struct(scratch.arena, &srl, &event->exception_code);
-    str8_serial_push_struct(scratch.arena, &srl, &event->string.size);
+    String8 string = event->string;
-    str8_serial_push_data(scratch.arena, &srl, event->string.str, event->string.size);
+    string.size = Min(string.size, max-srl.total_size);
+    str8_serial_push_struct(scratch.arena, &srl, &string.size);
+    str8_serial_push_data(scratch.arena, &srl, string.str, string.size);
   }
   String8 string = str8_serial_end(arena, &srl);
   scratch_end(scratch);
@@ -913,6 +915,7 @@ ctrl_init(void)
   ctrl_state->u2c_ring_mutex = os_mutex_alloc();
   ctrl_state->u2c_ring_cv = os_condition_variable_alloc();
   ctrl_state->c2u_ring_size = KB(64);
+  ctrl_state->c2u_ring_max_string_size = ctrl_state->c2u_ring_size/2;
   ctrl_state->c2u_ring_base = push_array_no_zero(arena, U8, ctrl_state->c2u_ring_size);
   ctrl_state->c2u_ring_mutex = os_mutex_alloc();
   ctrl_state->c2u_ring_cv = os_condition_variable_alloc();
@@ -2757,7 +2760,7 @@ ctrl_c2u_push_events(CTRL_EventList *events)
     for(CTRL_EventNode *n = events->first; n != 0; n = n ->next)
     {
       Temp scratch = scratch_begin(0, 0);
-      String8 event_srlzed = ctrl_serialized_string_from_event(scratch.arena, &n->v);
+      String8 event_srlzed = ctrl_serialized_string_from_event(scratch.arena, &n->v, ctrl_state->c2u_ring_size-sizeof(U64));
       OS_MutexScope(ctrl_state->c2u_ring_mutex) for(;;)
       {
         U64 unconsumed_size = (ctrl_state->c2u_ring_write_pos-ctrl_state->c2u_ring_read_pos);
@@ -3666,6 +3669,9 @@ ctrl_thread__next_dmn_event(Arena *arena, DMN_CtrlCtx *ctrl_ctx, CTRL_Msg *msg,
       out_evt->string     = module_path;
     }break;
     case DMN_EventKind_DebugString:
+    {
+      U64 num_strings = (event->string.size + ctrl_state->c2u_ring_max_string_size-1) / ctrl_state->c2u_ring_max_string_size;
+      for(U64 string_idx = 0; string_idx < num_strings; string_idx += 1)
       {
         CTRL_Event *out_evt = ctrl_event_list_push(scratch.arena, &evts);
         out_evt->kind       = CTRL_EventKind_DebugString;
@@ -3673,7 +3679,8 @@ ctrl_thread__next_dmn_event(Arena *arena, DMN_CtrlCtx *ctrl_ctx, CTRL_Msg *msg,
         out_evt->machine_id = CTRL_MachineID_Local;
         out_evt->entity     = event->thread;
         out_evt->parent     = event->process;
-      out_evt->string     = event->string;
+        out_evt->string     = str8_substr(event->string, r1u64(string_idx*ctrl_state->c2u_ring_max_string_size, (string_idx+1)*ctrl_state->c2u_ring_max_string_size));
+      }
     }break;
     case DMN_EventKind_SetThreadName:
     {

src/ctrl/ctrl_core.h

@@ -579,6 +579,7 @@ struct CTRL_State
   
   // rjf: ctrl -> user event ring buffer
   U64 c2u_ring_size;
+  U64 c2u_ring_max_string_size;
   U8 *c2u_ring_base;
   U64 c2u_ring_write_pos;
   U64 c2u_ring_read_pos;
@@ -677,7 +678,7 @@ internal CTRL_Event *ctrl_event_list_push(Arena *arena, CTRL_EventList *list);
 internal void ctrl_event_list_concat_in_place(CTRL_EventList *dst, CTRL_EventList *to_push);
 
 //- rjf: serialization
-internal String8 ctrl_serialized_string_from_event(Arena *arena, CTRL_Event *event);
+internal String8 ctrl_serialized_string_from_event(Arena *arena, CTRL_Event *event, U64 max);
 internal CTRL_Event ctrl_event_from_serialized_string(Arena *arena, String8 string);
 
 ////////////////////////////////

src/mule/mule_main.cpp

@@ -2297,6 +2297,14 @@ debug_string_tests(void)
   {
     OutputDebugStringA("Hello, World!\n");
   }
+  char message[65409+1];
+	memset(&message[0], '=', sizeof(message));
+	for(int i = 1; i < sizeof(message); i += 128)
+	{
+		message[i] = '\n';
+	}
+	message[sizeof(message) - 1] = 0;
+  OutputDebugStringA(message);
 #endif
 }