Simplify MDB_cursor: Drop flags C_ALLOCD,C_SHADOW.

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index d4f73282dec80df433024dfba36881d067e91624..08690fbd83a169746d104d0189688aef6e3fca1f 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -903,8 +903,6 @@ 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_ALLOCD       0x10            /**< Cursor was malloc'd */
 #define C_SPLITTING    0x20            /**< Cursor is in page_split */
 #define C_UNTRACK      0x40            /**< Un-track cursor when closing */
 /** @} */
@@ -1659,7 +1657,7 @@ mdb_cursor_shadow(MDB_txn *src, MDB_txn *dst)
                                mc->mc_dbflag = &dst->mt_dbflags[i];
                                mc->mc_snum = m2->mc_snum;
                                mc->mc_top = m2->mc_top;
-                               mc->mc_flags = m2->mc_flags | (C_SHADOW|C_ALLOCD);
+                               mc->mc_flags = m2->mc_flags;
                                for (j=0; j<mc->mc_snum; j++) {
                                        mc->mc_pg[j] = m2->mc_pg[j];
                                        mc->mc_ki[j] = m2->mc_ki[j];
@@ -1679,7 +1677,7 @@ mdb_cursor_shadow(MDB_txn *src, MDB_txn *dst)
                                        mx->mx_cursor.mc_dbflag = &mx->mx_dbflag;
                                        mx->mx_cursor.mc_snum = mx2->mx_cursor.mc_snum;
                                        mx->mx_cursor.mc_top = mx2->mx_cursor.mc_top;
-                                       mx->mx_cursor.mc_flags = mx2->mx_cursor.mc_flags | C_SHADOW;
+                                       mx->mx_cursor.mc_flags = mx2->mx_cursor.mc_flags;
                                        for (j=0; j<mx2->mx_cursor.mc_snum; j++) {
                                                mx->mx_cursor.mc_pg[j] = mx2->mx_cursor.mc_pg[j];
                                                mx->mx_cursor.mc_ki[j] = mx2->mx_cursor.mc_ki[j];
@@ -1698,7 +1696,7 @@ mdb_cursor_shadow(MDB_txn *src, MDB_txn *dst)
 /** Close this write txn's cursors, after optionally merging its shadow
  * cursors back into parent's.
  * @param[in] txn the transaction handle.
- * @param[in] merge 0 to not merge cursors, C_SHADOW to merge.
+ * @param[in] merge zero to not merge cursors, non-zero to merge.
  * @return 0 on success, non-zero on failure.
  */
 static void
@@ -1710,7 +1708,7 @@ mdb_cursors_close(MDB_txn *txn, unsigned merge)
        for (i = txn->mt_numdbs; --i >= 0; ) {
                for (mc = cursors[i]; mc; mc = next) {
                                next = mc->mc_next;
-                               if (mc->mc_flags & merge) {
+                               if (merge && mc->mc_orig) {
                                        MDB_cursor *m2 = mc->mc_orig;
                                        m2->mc_snum = mc->mc_snum;
                                        m2->mc_top = mc->mc_top;
@@ -1719,8 +1717,8 @@ mdb_cursors_close(MDB_txn *txn, unsigned merge)
                                                m2->mc_ki[j] = mc->mc_ki[j];
                                        }
                                }
-                               if (mc->mc_flags & C_ALLOCD)
-                                       free(mc);
+                               /* Only malloced cursors are permanently tracked. */
+                               free(mc);
                }
                cursors[i] = NULL;
        }
@@ -2359,7 +2357,7 @@ mdb_txn_commit(MDB_txn *txn)
                parent->mt_flags = txn->mt_flags;
 
                /* Merge our cursors into parent's and close them */
-               mdb_cursors_close(txn, C_SHADOW);
+               mdb_cursors_close(txn, 1);
 
                /* Update parent's DB table. */
                memcpy(parent->mt_dbs, txn->mt_dbs, txn->mt_numdbs * sizeof(MDB_db));
@@ -5914,7 +5912,6 @@ mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
                        txn->mt_cursors[dbi] = mc;
                        mc->mc_flags |= C_UNTRACK;
                }
-               mc->mc_flags |= C_ALLOCD;
        } else {
                return ENOMEM;
        }
@@ -5927,19 +5924,13 @@ mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
 int
 mdb_cursor_renew(MDB_txn *txn, MDB_cursor *mc)
 {
-       unsigned flags;
-
        if (txn == NULL || mc == NULL || mc->mc_dbi >= txn->mt_numdbs)
                return EINVAL;
 
        if ((mc->mc_flags & C_UNTRACK) || txn->mt_cursors)
                return EINVAL;
 
-       flags = mc->mc_flags;
-
        mdb_cursor_init(mc, txn, mc->mc_dbi, mc->mc_xcursor);
-
-       mc->mc_flags |= (flags & C_ALLOCD);
        return MDB_SUCCESS;
 }
 
@@ -5978,8 +5969,7 @@ mdb_cursor_close(MDB_cursor *mc)
                        if (*prev == mc)
                                *prev = mc->mc_next;
                }
-               if (mc->mc_flags & C_ALLOCD)
-                       free(mc);
+               free(mc);
        }
 }