Fix to only use shutdown_mutex internally in socket_common.c, and cre…

…ate a function to call the initialize of the mutex.

core/federated/RTI/rti_remote.c

@@ -1563,7 +1563,7 @@ void initialize_RTI(rti_remote_t* rti) {
 
   // Initialize thread synchronization primitives
   LF_MUTEX_INIT(&rti_mutex);
-  LF_MUTEX_INIT(&shutdown_mutex);
+  init_shutdown_mutex();
   LF_COND_INIT(&received_start_times, &rti_mutex);
   LF_COND_INIT(&sent_start_time, &rti_mutex);
 

core/federated/network/socket_common.c

@@ -396,6 +396,8 @@ void write_to_socket_fail_on_error(int* socket, size_t num_bytes, unsigned char*
   }
 }
 
+void init_shutdown_mutex(void) { LF_MUTEX_INIT(&shutdown_mutex); }
+
 int shutdown_socket(int* socket, bool read_before_closing) {
   LF_MUTEX_LOCK(&shutdown_mutex);
   if (*socket == -1) {

include/core/federated/network/socket_common.h

@@ -68,11 +68,6 @@
 
 typedef enum socket_type_t { TCP, UDP } socket_type_t;
 
-/**
- * Mutex protecting socket shutdown operations.
- */
-extern lf_mutex_t shutdown_mutex;
-
 /**
  * @brief Create an IPv4 TCP socket with Nagle's algorithm disabled
  * (TCP_NODELAY) and Delayed ACKs disabled (TCP_QUICKACK). Exits application
@@ -240,6 +235,11 @@ int write_to_socket_close_on_error(int* socket, size_t num_bytes, unsigned char*
 void write_to_socket_fail_on_error(int* socket, size_t num_bytes, unsigned char* buffer, lf_mutex_t* mutex,
                                    char* format, ...);
 
+/**
+ * Initialize shutdown mutex.
+ */
+void init_shutdown_mutex(void);
+
 /**
  * Shutdown and close the socket. If read_before_closing is false, it just immediately calls shutdown() with SHUT_RDWR
  * and close(). If read_before_closing is true, it calls shutdown with SHUT_WR, only disallowing further writing. Then,