Fix a bug that could cause traps or hangs if the DB_TXN->set_name function 

is used in a multithreaded application. [#14033]

*** txn/txn.c.orig	Tue Nov  1 06:50:03 2005

--- txn/txn.c	Tue Jan 31 15:05:13 2006

***************

*** 1049,1060 ****

--- 1049,1062 ----

  		return (ret);

  	memcpy(txn->name, name, len);

+ 	TXN_SYSTEM_LOCK(dbenv);

  	if (td->name != INVALID_ROFF) {

  		__db_shalloc_free(

  		    &mgr->reginfo, R_ADDR(&mgr->reginfo, td->name));

  		td->name = INVALID_ROFF;

  	}

  	if ((ret = __db_shalloc(&mgr->reginfo, len, 0, &p)) != 0) {

+ 		TXN_SYSTEM_UNLOCK(dbenv);

  		__db_err(dbenv,

  		    "Unable to allocate memory for transaction name");

***************

*** 1063,1068 ****

--- 1065,1071 ----

  		return (ret);

  	}

+ 	TXN_SYSTEM_UNLOCK(dbenv);

  	td->name = R_OFFSET(&mgr->reginfo, p);

  	memcpy(p, name, len);