[t:4880], fix toku_brtheader_get_some_existing_brt

git-svn-id: file:///svn/toku/tokudb@43434 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt_header.c

@@ -550,7 +550,7 @@ int toku_remove_brtheader (struct brt_header* h, char **error_string, BOOL oplsn
 BRT toku_brtheader_get_some_existing_brt(struct brt_header* h) {
     BRT brt_ret = NULL;
     toku_brtheader_lock(h);
-    if (toku_list_empty(&h->live_brts)) {
+    if (!toku_list_empty(&h->live_brts)) {
         brt_ret = toku_list_struct(toku_list_head(&h->live_brts), struct brt, live_brt_link);
     }
     toku_brtheader_unlock(h);
@@ -826,8 +826,10 @@ static int find_xid (OMTVALUE v, void *txnv) {
     return 0;
 }
 
-void
+// returns if ref was added
+BOOL
 toku_brtheader_maybe_add_txn_ref(struct brt_header* h, TOKUTXN txn) {
+    BOOL ref_added = FALSE;
     OMTVALUE txnv;
     u_int32_t index;
     toku_brtheader_lock(h);
@@ -836,13 +838,16 @@ toku_brtheader_maybe_add_txn_ref(struct brt_header* h, TOKUTXN txn) {
     if (r==0) {
         // It's already there.
         assert((TOKUTXN)txnv==txn);
-        return 0;
+        ref_added = FALSE;
     }
     // Otherwise it's not there.
     // Insert reference to transaction into brt
     r = toku_omt_insert_at(h->txns, txn, index);
     assert(r==0);
+    ref_added = TRUE;
+exit:
     toku_brtheader_unlock(h);
+    return ref_added;
 }
 
 void

newbrt/brt_header.h

@@ -53,7 +53,7 @@ void toku_reset_root_xid_that_created(struct brt_header* h, TXNID new_root_xid_t
 // This redefines which xid created the dictionary.
 
 
-void
+BOOL
 toku_brtheader_maybe_add_txn_ref(struct brt_header* h, TOKUTXN txn);
 void
 toku_brtheader_remove_txn_ref(struct brt_header* h, TOKUTXN txn);

newbrt/rollback.c

@@ -685,10 +685,12 @@ static int find_filenum (OMTVALUE v, void *hv) {
 
 //Notify a transaction that it has touched a brt.
 int toku_txn_note_brt (TOKUTXN txn, struct brt_header* h) {
-    toku_brtheader_maybe_add_txn_ref(h, txn);
+    BOOL ref_added = toku_brtheader_maybe_add_txn_ref(h, txn);
     // Insert reference to brt into transaction
+    if (ref_added) {
         int r = toku_omt_insert(txn->open_brt_headers, h, find_filenum, h, 0);
         assert(r==0);
+    }
     return 0;
 }