Only free malloc'd cursors

diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 28d5001..ae2e77c 100644 (file)
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -790,7 +790,8 @@ struct MDB_cursor {
 #define C_INITIALIZED  0x01    /**< cursor has been initialized and is valid */
 #define C_EOF  0x02                    /**< No more data */
 #define C_SUB  0x04                    /**< Cursor is a sub-cursor */
-#define C_SHADOW       0x08                    /**< Cursor is a dup from a parent txn */
+#define C_SHADOW       0x08            /**< Cursor is a dup from a parent txn */
+#define C_ALLOCD       0x10            /**< Cursor was malloc'd */
 /** @} */
        unsigned int    mc_flags;       /**< @ref mdb_cursor */
        MDB_page        *mc_pg[CURSOR_STACK];   /**< stack of pushed pages */
@@ -1316,7 +1317,8 @@ mdb_cursor_merge(MDB_txn *txn)
                                                m2->mc_ki[j] = mc->mc_ki[j];
                                        }
                                }
-                               free(mc);
+                               if (mc->mc_flags & C_ALLOCD)
+                                       free(mc);
                        }
                }
        }
@@ -1517,7 +1519,8 @@ mdb_txn_reset0(MDB_txn *txn)
                                MDB_cursor *mc;
                                while ((mc = txn->mt_cursors[i])) {
                                        txn->mt_cursors[i] = mc->mc_next;
-                                       free(mc);
+                                       if (mc->mc_flags & C_ALLOCD)
+                                               free(mc);
                                }
                        }
                }
@@ -4620,6 +4623,7 @@ mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
                        mc->mc_next = txn->mt_cursors[dbi];
                        txn->mt_cursors[dbi] = mc;
                }
+               mc->mc_flags |= C_ALLOCD;
        } else {
                return ENOMEM;
        }
@@ -4664,7 +4668,8 @@ mdb_cursor_close(MDB_cursor *mc)
                        if (*prev == mc)
                                *prev = mc->mc_next;
                }
-               free(mc);
+               if (mc->mc_flags & C_ALLOCD)
+                       free(mc);
        }
 }