debug mods

diff --git a/metadata_hub.c b/metadata_hub.c
index 59130823541d2beded91df2640e66331a79ca21d..591ab02f2c06eedfce8301998539667c5e9318dc 100644 (file)
--- a/metadata_hub.c
+++ b/metadata_hub.c
@@ -127,14 +127,25 @@ void metadata_hub_unlock_hub_mutex_cleanup(__attribute__((unused)) void *arg) {
   pthread_rwlock_unlock(&metadata_hub_re_lock);
 }
 
+char *last_metadata_hub_modify_prolog_file = NULL;
+int last_metadata_hub_modify_prolog_line;
+
 void _metadata_hub_modify_prolog(const char *filename, const int linenumber) {
   // always run this before changing an entry or a sequence of entries in the metadata_hub
   // debug(1, "locking metadata hub for writing");
   if (pthread_rwlock_trywrlock(&metadata_hub_re_lock) != 0) {
-    debug(1, "Metadata_hub write lock is already taken -- must wait.");
+    if (last_metadata_hub_modify_prolog_file)
+       debug(1, "Metadata_hub write lock is already taken at \"%s:%d\" -- must wait.", last_metadata_hub_modify_prolog_file, last_metadata_hub_modify_prolog_line);
+    else
+       debug(1, "Metadata_hub write lock is already taken by unknown -- must wait.");
     pthread_rwlock_wrlock(&metadata_hub_re_lock);
     debug(1, "Okay -- acquired the metadata_hub write lock.");
   } else {
+       if (last_metadata_hub_modify_prolog_file) {
+               free(last_metadata_hub_modify_prolog_file);
+       }
+       last_metadata_hub_modify_prolog_file = strdup(filename);
+       last_metadata_hub_modify_prolog_line = linenumber;
     debug(3, "Metadata_hub write lock acquired.");
   }
 }
@@ -145,6 +156,10 @@ void _metadata_hub_modify_epilog(int modified, const char *filename, const int l
   if (modified) {
     run_metadata_watchers();
   }
+  if (last_metadata_hub_modify_prolog_file) {
+               free(last_metadata_hub_modify_prolog_file);
+               last_metadata_hub_modify_prolog_file = NULL;
+  }
   pthread_rwlock_unlock(&metadata_hub_re_lock);
   debug(3, "Metadata_hub write lock unlocked.");
 }