2 files changed, 40 insertions, 1 deletions
diff --git a/src/os_unix.c b/src/os_unix.c
index 9b6afe537..a45aaa1d7 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -925,7 +925,15 @@ static void releaseOpenCnt(struct unixOpenCnt *pOpen){
         assert( pOpen->pNext->pPrev==pOpen );
         pOpen->pNext->pPrev = pOpen->pPrev;
       }
-      assert( !pOpen->pUnused );
+      assert( !pOpen->pUnused || threadsOverrideEachOthersLocks==0 );
+
+      /* If pOpen->pUnused is not null, then memory and file-descriptors
+      ** are leaked.
+      **
+      ** This will only happen if, under Linuxthreads, the user has opened
+      ** a transaction in one thread, then attempts to close the database
+      ** handle from another thread (without first unlocking the db file).
+      ** This is a misuse.  */
       sqlite3_free(pOpen);
     }
   }
diff --git a/src/test4.c b/src/test4.c
index c51d2a640..654b572db 100644
--- a/src/test4.c
+++ b/src/test4.c
@@ -651,6 +651,36 @@ static int tcl_thread_db_get(
 }
 
 /*
+** Usage: thread_db_put ID DB
+**
+*/
+static int tcl_thread_db_put(
+  void *NotUsed,
+  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
+  int argc,              /* Number of arguments */
+  const char **argv      /* Text of each argument */
+){
+  int i;
+  extern int sqlite3TestMakePointerStr(Tcl_Interp*, char*, void*);
+  extern void *sqlite3TestTextToPtr(const char *);
+  if( argc!=3 ){
+    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
+       " ID DB", 0);
+    return TCL_ERROR;
+  }
+  i = parse_thread_id(interp, argv[1]);
+  if( i<0 ) return TCL_ERROR;
+  if( !threadset[i].busy ){
+    Tcl_AppendResult(interp, "no such thread", 0);
+    return TCL_ERROR;
+  }
+  thread_wait(&threadset[i]);
+  assert( !threadset[i].db );
+  threadset[i].db = (sqlite3*)sqlite3TestTextToPtr(argv[2]);
+  return TCL_OK;
+}
+
+/*
 ** Usage: thread_stmt_get ID
 **
 ** Return the database stmt pointer for the given thread.  Then
@@ -704,6 +734,7 @@ int Sqlitetest4_Init(Tcl_Interp *interp){
      { "thread_finalize",   (Tcl_CmdProc*)tcl_thread_finalize   },
      { "thread_swap",       (Tcl_CmdProc*)tcl_thread_swap       },
      { "thread_db_get",     (Tcl_CmdProc*)tcl_thread_db_get     },
+     { "thread_db_put",     (Tcl_CmdProc*)tcl_thread_db_put     },
      { "thread_stmt_get",   (Tcl_CmdProc*)tcl_thread_stmt_get   },
   };
   int i;