Add crash logger

demo/main.c

@@ -248,6 +248,8 @@ static void endpoint_index(CWEB *cweb, CWEB_Request *req)
 {
     (void) cweb;
 
+    __builtin_trap(); // TODO: remove me
+
     cweb_respond_template(req, 200, CWEB_STR("demo/pages/index.wl"));
 }
 
@@ -335,6 +337,10 @@ int main(void)
     if (cweb_global_init() < 0)
         return -1;
 
+    char buf[128];
+    int len = snprintf(buf, sizeof(buf), "crash_%d.txt", getpid());
+    cweb_enable_crash_logger((CWEB_String) { buf, len });
+
     uint16_t    secure_port = 0;
     CWEB_String cert_key;
     CWEB_String private_key;