Register c-node globally and remove no-longer needed services

lib/bacnet.ex

@@ -2,4 +2,21 @@ defmodule Bacnet do
   @moduledoc """
   BACNet client.
   """
+
+  use GenServer
+
+  require Logger
+
+  @spec start_link(any) :: GenServer.on_start()
+  def start_link(_opts) do
+    GenServer.start_link(__MODULE__, nil, name: __MODULE__)
+  end
+
+  @impl GenServer
+  def init(_) do
+    {:ok, nil}
+  end
+
+  @doc false
+  defdelegate ei_log(level, term), to: Logger, as: :log
 end

lib/bacnet/application.ex

@@ -13,8 +13,7 @@ defmodule Bacnet.Application do
 
   defp children() do
     [
-      {Bacnet.Logger, nil},
-      {Bacnet.Heartbeat, nil},
+      {Bacnet, nil},
       {MuonTrap.Daemon, [bacnetd_exec(), bacnetd_args(), []]}
     ]
   end

src/ei_client.c

@@ -5,7 +5,7 @@
 
 #include "ei_client.h"
 
-#define OTP_COMPAT_VER 25
+#define OTP_COMPAT_VER 24
 #define HEARTBEAT_PROCESS "Elixir.Bacnet.Heartbeat"
 #define CNODE_NAME "bacnetd"
 
@@ -53,6 +53,11 @@ bool ei_client_config(const char *nodename, const char *cookie)
     return false;
   }
 
+  erlang_pid *pid = ei_self(&client.cnode);
+  if (ei_global_register(client.fd, CNODE_NAME, pid) == -1) {
+    return false;
+  }
+
   client.ready = true;
 
   return true;
@@ -72,6 +77,28 @@ bool ei_client_send(char *process_name, ei_x_buff *msg)
   return ret == 0 ? true : false;
 }
 
+bool ei_client_call(char *module, char *func, ei_x_buff *args, ei_x_buff *out)
+{
+  pthread_mutex_lock(&client.lock);
+  int ret = ei_rpc(&client.cnode, client.fd, module, func, args->buff,
+                   args->index, out);
+  pthread_mutex_unlock(&client.lock);
+
+  return ret == -1 ? false : true;
+}
+
+bool ei_client_recv(erlang_msg *meta, ei_x_buff *msg)
+{
+  pthread_mutex_lock(&client.lock);
+  int ret = ei_xreceive_msg(client.fd, meta, msg);
+  pthread_mutex_unlock(&client.lock);
+  if (ret == ERL_ERROR) {
+    return false;
+  }
+
+  return true;
+}
+
 static void ei_free()
 {
   if (client.fd != NULL) {

src/ei_client.h

@@ -3,9 +3,9 @@
 
 #include <ei.h>
 
-typedef void(msg_handler_cb_t)(erlang_msg *msg, ei_x_buff *data);
-
 bool ei_client_config(const char *nodename, const char *cookie);
 bool ei_client_send(char *process_name, ei_x_buff *msg);
+bool ei_client_call(char *module, char *func, ei_x_buff *msg, ei_x_buff *out);
+bool ei_client_recv(erlang_msg *meta, ei_x_buff *msg);
 
 #endif /* EI_CLIENT_H */

src/ei_log.c

@@ -10,26 +10,31 @@ static const char *level_to_str(log_level_t level);
 
 void ei_log(log_level_t level, const char *format, ...)
 {
-  va_list args;
-  va_start(args, format);
+  va_list vargs;
+  va_start(vargs, format);
 
   char log_buffer[MAX_LOG_LEN];
-  int log_len = snprintf(log_buffer, sizeof(log_buffer), format, args);
+  int log_len = vsnprintf(log_buffer, sizeof(log_buffer), format, vargs);
 
-  ei_x_buff msg;
-  ei_x_new_with_version(&msg);
-  ei_x_encode_tuple_header(&msg, 2);
-  ei_x_encode_atom(&msg, level_to_str(level));
-  ei_x_encode_binary(&msg, log_buffer, log_len);
+  ei_x_buff out;
+  ei_x_new(&out);
 
-  if (!ei_client_send("Elixir.Bacnet.Logger", &msg)) {
+  ei_x_buff args;
+  ei_x_new(&args);
+  ei_x_encode_list_header(&args, 2);
+  ei_x_encode_atom(&args, level_to_str(level));
+  ei_x_encode_binary(&args, log_buffer, log_len);
+  ei_x_encode_empty_list(&args);
+
+  if (!ei_client_call("Elixir.Bacnet", "ei_log", &args, &out)) {
     char new_format[MAX_LOG_LEN];
     snprintf(new_format, sizeof(new_format), "%s\n", format);
-    vprintf(new_format, args);
+    vprintf(new_format, vargs);
   }
 
-  ei_x_free(&msg);
-  va_end(args);
+  ei_x_free(&out);
+  ei_x_free(&args);
+  va_end(vargs);
 }
 
 static const char *level_to_str(log_level_t level)

src/ei_log.h

@@ -1,10 +1,14 @@
 #ifndef EI_LOG_H
 #define EI_LOG_H
 
-#define LOG_ERR(format, ...) ei_log(ERROR, format __VA_ARGS__)
-#define LOG_WRN(format, ...) ei_log(WARNING, format __VA_ARGS__)
-#define LOG_INF(format, ...) ei_log(INFO, format __VA_ARGS__)
-#define LOG_DBG(format, ...) ei_log(DEBUG, format __VA_ARGS__)
+#define LOG_EME(format, ...) ei_log(EMERGENCY, format, ##__VA_ARGS__)
+#define LOG_ALE(format, ...) ei_log(ALERT, format, ##__VA_ARGS__)
+#define LOG_CRT(format, ...) ei_log(CRITICAL, format, ##__VA_ARGS__)
+#define LOG_ERR(format, ...) ei_log(ERROR, format, ##__VA_ARGS__)
+#define LOG_WRN(format, ...) ei_log(WARNING, format, ##__VA_ARGS__)
+#define LOG_NTC(format, ...) ei_log(NOTICE, format, ##__VA_ARGS__)
+#define LOG_INF(format, ...) ei_log(INFO, format, ##__VA_ARGS__)
+#define LOG_DBG(format, ...) ei_log(DEBUG, format, ##__VA_ARGS__)
 
 typedef enum {
   EMERGENCY,

src/main.c

@@ -3,30 +3,60 @@
 #include "arg.h"
 #include "bacnet/datalink/dlenv.h"
 #include "ei_client.h"
-#include "ei_heartbeat.h"
 #include "ei_log.h"
 
 static arg_t args;
+static void unimplemented(const char *msg_type);
 
 int main(int argc, char **argv)
 {
   dlenv_init();
-
   args_parse(&args, argc, argv);
 
   if (!ei_client_config(args.nodename, args.cookie)) {
-    LOG_ERR("Failed to start ei client");
+    LOG_ERR("bacnetd: unable to establish connection");
     return -1;
   }
 
-  if (!ei_heartbeat_start()) {
-    LOG_ERR("Heartbeat failed to start");
-    return -1;
-  }
+  LOG_DBG("bacnetd: process started");
 
   while (1) {
-    pause();
+    erlang_msg meta;
+    ei_x_buff msg;
+    ei_x_new(&msg);
+
+    if (!ei_client_recv(&meta, &msg)) {
+      goto cleanup;
+    }
+
+    int index = 0;
+    int version = 0;
+    int arity = 0;
+    char msg_type[MAXATOMLEN] = { 0 };
+
+    char *buf = msg.buff;
+    bool bad_msg = (false
+          || ei_decode_version(buf, &index, &version)
+          || ei_decode_tuple_header(buf, &index, &arity)
+          || (arity < 2)
+          || ei_decode_atom(buf, &index, msg_type));
+
+    if (bad_msg) {
+      goto cleanup;
+    }
+
+    if (strcmp(msg_type, "$gen_call") == 0) {
+      unimplemented("$gen_call");
+    }
+
+  cleanup:
+    ei_x_free(&msg);
   }
 
   return 0;
 }
+
+static void unimplemented(const char *msg_type)
+{
+  LOG_WRN("bacnetd: %s unimplemented", msg_type);
+}