Move the snapshot code out of the btree engine and up into the session

layer (makes the layering better, but still not right).

1 files changed, 58 insertions, 0 deletions

diff --git a/src/session/session_salvage.c b/src/session/session_salvage.c
new file mode 100644
index 00000000000..046557c71d6
--- /dev/null
+++ b/src/session/session_salvage.c
@@ -0,0 +1,58 @@
+/*-
+ * Copyright (c) 2008-2012 WiredTiger, Inc.
+ *	All rights reserved.
+ *
+ * See the file LICENSE for redistribution information.
+ */
+
+#include "wt_internal.h"
+
+/*
+ * __wt_salvage --
+ *	Salvage a single file.
+ */
+int
+__wt_salvage(WT_SESSION_IMPL *session, const char *cfg[])
+{
+	WT_BTREE *btree;
+	WT_DECL_RET;
+	WT_SNAPSHOT snapbase[2];
+
+	btree = session->btree;
+
+	/*
+	 * XXX
+	 * The salvage process reads and discards previous snapshot blocks, so
+	 * the underlying block manager has to ignore any previous snapshot
+	 * entries when creating a new snapshot, in other words, we can't use
+	 * the metadata snapshot list, it has all of those snapshots listed and
+	 * we don't care about them.  Build a clean snapshot array and use it
+	 * instead.
+	 *
+	 * Don't first clear the metadata snapshot list and call the snapshot
+	 * get routine: a crash between clearing the metadata snapshot list and
+	 * creating a new snapshot list would look like a create or open of a
+	 * file without a snapshot from which to roll-forward, and the contents
+	 * of the file would be discarded.
+	 */
+	memset(snapbase, 0, sizeof(snapbase));
+
+	WT_RET(__wt_strdup(session, WT_INTERNAL_SNAPSHOT, &snapbase[0].name));
+	F_SET(&snapbase[0], WT_SNAP_ADD);
+
+	WT_ERR(__wt_bt_salvage(session, snapbase, cfg));
+
+	/*
+	 * If no snapshot was created, well, it's probably bad news, but there
+	 * is nothing to do but clear any recorded snapshots for the file.  If
+	 * a snapshot was created, life is good, replace any recorded snapshots
+	 * with the new one.
+	 */
+	if (snapbase[0].raw.data == NULL)
+		WT_ERR(__wt_meta_snapshot_clear(session, btree->name));
+	else
+		WT_ERR(__wt_meta_snaplist_set(session, btree->name, snapbase));
+
+err:	__wt_free(session, snapbase[0].name);
+	return (0);
+}