Several changes to the db rename feature.

	Renaming locks the target lock file.
	If the target lock file doesn't exist, create it.
	Check the return value of krb5_dbm_db_set_name and set the
		context accordingly if the target didn't exist.
	Only unlink the source lock file if one could be computed.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@7418 dc483132-0cff-0310-8789-dd5450dbe970

1 files changed, 25 insertions, 19 deletions

diff --git a/src/lib/kdb/kdb_dbm.c b/src/lib/kdb/kdb_dbm.c
index 1d61c622f..b80a0a65c 100644
--- a/src/lib/kdb/kdb_dbm.c
+++ b/src/lib/kdb/kdb_dbm.c
@@ -886,31 +886,36 @@ krb5_dbm_db_rename(context, from, to)
     context->db_context = (void *) NULL;
     if (!(retval = k5dbm_init_context(context))) {
 	/*
-	 * Set the name of our temporary database context to the target
-	 * database.  We need to do this so that the database calls do the
-	 * operations to the right lock file.
+	 * Set the database to the target, so that other processes sharing
+	 * the target will stop their activity, and notice the new database.
 	 */
 	retval = krb5_dbm_db_set_name(context, to);
-	db_ctx = (krb5_db_context *) context->db_context;
-	if ((db_ctx->db_lf_name = gen_dbsuffix(db_ctx->db_name,
-					       KDBM_LOCK_EXT(db_ctx)))) {
-	    if ((db_ctx->db_lf_file = open(db_ctx->db_lf_name,
-					   O_RDWR|O_EXCL|O_CREAT, 0600)) >= 0){
-		db_ctx->db_inited = 1;
-		if ((retval = krb5_dbm_db_get_age(context,
-						  NULL,
-						  &db_ctx->db_lf_time)))
-		    goto errout;
-	    }
-	    else {
-		retval = errno;
+	if (retval) {
+	    if (retval == ENOENT)
+		db_ctx->db_name = strdup(to);
+	    else
 		goto errout;
-	    }
 	}
-	else {
+	
+	db_ctx = (krb5_db_context *) context->db_context;
+	db_ctx->db_lf_name = gen_dbsuffix(db_ctx->db_name,
+					  KDBM_LOCK_EXT(db_ctx));
+	if (db_ctx->db_lf_name == (char *)NULL) {
 	    retval = ENOMEM;
 	    goto errout;
 	}
+
+	db_ctx->db_lf_file = open(db_ctx->db_lf_name, O_RDWR|O_CREAT, 0600);
+	if (db_ctx->db_lf_file < 0) {
+	    retval = errno;
+	    goto errout;
+	}
+
+	db_ctx->db_inited = 1;
+
+	retval = krb5_dbm_db_get_age(context, NULL, &db_ctx->db_lf_time);
+	if (retval)
+	    goto errout;
     }
     else
 	return(retval);
@@ -953,7 +958,8 @@ krb5_dbm_db_rename(context, from, to)
 	((!frompag && !topag) ||
 	 (frompag && topag && (rename (frompag, topag) == 0)))) {
 	    /* We only need to unlink the source lock file */
-	    (void) unlink(fromok);
+	    if (fromok)
+		(void) unlink(fromok);
 	    retval = krb5_dbm_db_end_update(context);
     } else {
 	    (void) krb5_dbm_db_end_update(context);