Make set_transaction functions use intra process mutex -- Phase 1

Phase 2 will be inter-process named mutexes
https://github.com/Hamlib/Hamlib/issues/942

include/hamlib/rig.h

@@ -33,6 +33,10 @@
 #include <inttypes.h>
 #include <time.h>
 #include <sys/time.h>
+#include "config.h"
+#ifdef HAVE_PTHREAD
+#include <pthread.h>
+#endif
 
 /* Rig list is in a separate file so as not to mess up w/ this one */
 #include <hamlib/riglist.h>
@@ -2447,6 +2451,9 @@ struct rig_state {
     void *async_data_handler_priv_data;
     volatile int poll_routine_thread_run;
     void *poll_routine_priv_data;
+#ifdef HAVE_PTHREAD
+    pthread_mutex_t mutex_set_transaction;
+#endif
 };
 
 //! @cond Doxygen_Suppress

src/misc.h

@@ -26,13 +26,15 @@
 
 
 /*
- * Careful!! These macros are NOT reentrant!
- * ie. they may not be executed atomically,
- * thus not ensure mutual exclusion.
- * Fix it when making Hamlib reentrant!  --SF
  */
+#ifdef HAVE_PTHREAD
+#include <pthread.h>
+#define set_transaction_active(rig) {pthread_mutex_lock(&rig->state.mutex_set_transaction);(rig)->state.transaction_active = 1;}
+#define set_transaction_inactive(rig) {(rig)->state.transaction_active = 0;pthread_mutex_unlock(&rig->state.mutex_set_transaction);}
+#else
 #define set_transaction_active(rig) {(rig)->state.transaction_active = 1;}
 #define set_transaction_inactive(rig) {(rig)->state.transaction_active = 0;}
+#endif
 
 __BEGIN_DECLS
 

src/rig.c

@@ -451,6 +451,9 @@ RIG *HAMLIB_API rig_init(rig_model_t rig_model)
      * TODO: read the Preferences here!
      */
     rs = &rig->state;
+#ifdef HAVE_PTHREAD
+    pthread_mutex_init(&rs->mutex_set_transaction, NULL);
+#endif
 
     rs->async_data_enabled = 0;
     rs->rigport.fd = -1;