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-rw-r--r--transaction.go245
1 files changed, 154 insertions, 91 deletions
diff --git a/transaction.go b/transaction.go
index 4ca2d35..4525a31 100644
--- a/transaction.go
+++ b/transaction.go
@@ -1,44 +1,143 @@
package bolt
-// TODO: #define DB_DIRTY 0x01 /**< DB was modified or is DUPSORT data */
-// TODO: #define DB_STALE 0x02 /**< Named-DB record is older than txnID */
-// TODO: #define DB_NEW 0x04 /**< Named-DB handle opened in this txn */
-// TODO: #define DB_VALID 0x08 /**< DB handle is valid, see also #MDB_VALID */
+var TransactionExistingChildError = &Error{"txn already has a child", nil}
+var TransactionReadOnlyChildError = &Error{"read-only txn cannot create a child", nil}
-// TODO: #define MDB_TXN_RDONLY 0x01 /**< read-only transaction */
-// TODO: #define MDB_TXN_ERROR 0x02 /**< an error has occurred */
-// TODO: #define MDB_TXN_DIRTY 0x04 /**< must write, even if dirty list is empty */
-// TODO: #define MDB_TXN_SPILLS 0x08 /**< txn or a parent has spilled pages */
+const (
+ txnb_dirty = 0x01 /**< DB was modified or is DUPSORT data */
+ txnb_stale = 0x02 /**< Named-DB record is older than txnID */
+ txnb_new = 0x04 /**< Named-DB handle opened in this txn */
+ txnb_valid = 0x08 /**< DB handle is valid, see also #MDB_VALID */
+)
-type Transaction interface {
-}
+const (
+ ps_modify = 1
+ ps_rootonly = 2
+ ps_first = 4
+ ps_last = 8
+)
+
+type Transaction struct {
+ id int
+ db *DB
+ writable bool
+ dirty bool
+ spilled bool
+ err error
+ parent *Transaction
+ child *Transaction
+ buckets []*txnbucket
-type transaction struct {
- id int
- flags int
- db *DB
- parent *transaction
- child *transaction
- nextPageNumber int
- freePages []int
- spillPages []int
- dirtyList []int
- reader *reader
+ pgno int
+ freePages []pgno
+ spillPages []pgno
+ dirtyList []pgno
+ reader *reader
// TODO: bucketxs []*bucketx
- buckets []*Bucket
- bucketFlags []int
- cursors []*cursor
// Implicit from slices? TODO: MDB_dbi mt_numdbs;
- mt_dirty_room int
+ dirty_room int
+ pagestate pagestate
+}
+
+type txnbucket struct {
+ bucket *Bucket
+ cursor *Cursor
+ flags int
+}
+
+// Transaction begins a nested child transaction. Child transactions are only
+// available to writable transactions and a transaction can only have one child
+// at a time.
+func (t *Transaction) Transaction() (*Transaction, error) {
+ // Exit if parent already has a child transaction.
+ if t.child != nil {
+ return nil, TransactionExistingChildError
+ }
+ // Exit if using parent for read-only transaction.
+ if !t.writable {
+ return nil, TransactionReadOnlyChildError
+ }
+ // TODO: Exit if parent is in an error state.
+
+ // Create the child transaction and attach the parent.
+ child := &Transaction{
+ id: t.id,
+ db: t.db,
+ parent: t,
+ writable: true,
+ pgno: t.pgno,
+ pagestate: t.db.pagestate,
+ }
+ copy(child.buckets, t.buckets)
+
+ // TODO: Remove DB_NEW flag.
+ t.child = child
+
+ // TODO: wtf?
+ // if (env->me_pghead) {
+ // size = MDB_IDL_SIZEOF(env->me_pghead);
+ // env->me_pghead = mdb_midl_alloc(env->me_pghead[0]);
+ // if (env->me_pghead)
+ // memcpy(env->me_pghead, ntxn->mnt_pgstate.mf_pghead, size);
+ // else
+ // rc = ENOMEM;
+ // }
+
+ // TODO: Back up parent transaction's cursors.
+ // if t.shadow(child); err != nil {
+ // child.reset0()
+ // return err
+ // }
+
+ return child, nil
}
-// ntxn represents a nested transaction.
-type ntxn struct {
- transaction *transaction /**< the transaction */
- pageState pageState /**< parent transaction's saved freestate */
+func (t *Transaction) Cursor(b *Bucket) (*Cursor, error) {
+ // TODO: if !(txn->mt_dbflags[dbi] & DB_VALID) return InvalidBucketError
+ // TODO: if (txn->mt_flags & MDB_TXN_ERROR) return BadTransactionError
+
+ // Allow read access to the freelist
+ // TODO: if (!dbi && !F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
+
+ /*
+ MDB_cursor *mc;
+ size_t size = sizeof(MDB_cursor);
+
+ // Allow read access to the freelist
+ if (!dbi && !F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
+ return EINVAL;
+
+ if ((mc = malloc(size)) != NULL) {
+ mdb_cursor_init(mc, txn, dbi, (MDB_xcursor *)(mc + 1));
+ if (txn->mt_cursors) {
+ mc->mc_next = txn->mt_cursors[dbi];
+ txn->mt_cursors[dbi] = mc;
+ mc->mc_flags |= C_UNTRACK;
+ }
+ } else {
+ return ENOMEM;
+ }
+
+ *ret = mc;
+
+ return MDB_SUCCESS;
+ */
+ return nil, nil
}
-func (t *transaction) allocPage(num int) *page {
+// //
+// //
+// //
+// //
+// //
+// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ CONVERTED ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ //
+// //
+// //
+// //
+// //
+// //
+
+func (t *Transaction) allocPage(num int) *page {
/*
MDB_env *env = txn->mt_env;
MDB_page *ret = env->me_dpages;
@@ -74,7 +173,7 @@ func (t *transaction) allocPage(num int) *page {
}
// Find oldest txnid still referenced. Expects txn->mt_txnid > 0.
-func (t *transaction) oldest() int {
+func (t *Transaction) oldest() int {
/*
int i;
txnid_t mr, oldest = txn->mt_txnid - 1;
@@ -94,7 +193,7 @@ func (t *transaction) oldest() int {
}
// Add a page to the txn's dirty list
-func (t *transaction) dirty(p *page) {
+func (t *Transaction) addDirtyPage(p *page) {
/*
MDB_ID2 mid;
int rc, (*insert)(MDB_ID2L, MDB_ID2 *);
@@ -119,7 +218,7 @@ func (t *transaction) dirty(p *page) {
// @param[in] mp the page being referenced. It must not be dirty.
// @param[out] ret the writable page, if any. ret is unchanged if
// mp wasn't spilled.
-func (t *transaction) unspill(p *page) *page {
+func (t *Transaction) unspill(p *page) *page {
/*
MDB_env *env = txn->mt_env;
const MDB_txn *tx2;
@@ -173,7 +272,7 @@ func (t *transaction) unspill(p *page) *page {
}
// Back up parent txn's cursors, then grab the originals for tracking
-func (t *transaction) shadow(dst *transaction) error {
+func (t *Transaction) shadow(dst *Transaction) error {
/*
MDB_cursor *mc, *bk;
MDB_xcursor *mx;
@@ -214,7 +313,7 @@ func (t *transaction) shadow(dst *transaction) error {
// @param[in] txn the transaction handle.
// @param[in] merge true to keep changes to parent cursors, false to revert.
// @return 0 on success, non-zero on failure.
-func (t *transaction) closeCursors(merge bool) {
+func (t *Transaction) closeCursors(merge bool) {
/*
MDB_cursor **cursors = txn->mt_cursors, *mc, *next, *bk;
MDB_xcursor *mx;
@@ -252,7 +351,7 @@ func (t *transaction) closeCursors(merge bool) {
// Common code for #mdb_txn_begin() and #mdb_txn_renew().
// @param[in] txn the transaction handle to initialize
// @return 0 on success, non-zero on failure.
-func (t *transaction) renew() error {
+func (t *Transaction) renew() error {
/*
MDB_env *env = txn->mt_env;
MDB_txninfo *ti = env->me_txns;
@@ -366,7 +465,7 @@ func (t *transaction) renew() error {
return nil
}
-func (t *transaction) Renew() error {
+func (t *Transaction) Renew() error {
/*
int rc;
@@ -389,12 +488,12 @@ func (t *transaction) Renew() error {
return nil
}
-func (t *transaction) DB() *DB {
+func (t *Transaction) DB() *DB {
return t.db
}
// Export or close DBI handles opened in this txn.
-func (t *transaction) updateBuckets(keep bool) {
+func (t *Transaction) updateBuckets(keep bool) {
/*
int i;
MDB_dbi n = txn->mt_numdbs;
@@ -423,7 +522,7 @@ func (t *transaction) updateBuckets(keep bool) {
// May be called twice for readonly txns: First reset it, then abort.
// @param[in] txn the transaction handle to reset
// @param[in] act why the transaction is being reset
-func (t *transaction) reset(act string) {
+func (t *Transaction) reset(act string) {
/*
MDB_env *env = txn->mt_env;
@@ -472,7 +571,7 @@ func (t *transaction) reset(act string) {
*/
}
-func (t *transaction) Reset() {
+func (t *Transaction) Reset() {
/*
if (txn == NULL)
return;
@@ -485,7 +584,7 @@ func (t *transaction) Reset() {
*/
}
-func (t *transaction) Abort() {
+func (t *Transaction) Abort() {
/*
if (txn == NULL)
return;
@@ -504,7 +603,7 @@ func (t *transaction) Abort() {
// Save the freelist as of this transaction to the freeDB.
// This changes the freelist. Keep trying until it stabilizes.
-func (t *transaction) saveFreelist() error {
+func (t *Transaction) saveFreelist() error {
/*
// env->me_pghead[] can grow and shrink during this call.
// env->me_pglast and txn->mt_free_pgs[] can only grow.
@@ -662,7 +761,7 @@ func (t *transaction) saveFreelist() error {
// @param[in] txn the transaction that's being committed
// @param[in] keep number of initial pages in dirty_list to keep dirty.
// @return 0 on success, non-zero on failure.
-func (t *transaction) flush(keep bool) error {
+func (t *Transaction) flush(keep bool) error {
/*
MDB_env *env = txn->mt_env;
MDB_ID2L dl = txn->mt_u.dirty_list;
@@ -1005,7 +1104,7 @@ func (t *transaction) flush(keep bool) error {
// Update the environment info to commit a transaction.
// @param[in] txn the transaction that's being committed
// @return 0 on success, non-zero on failure.
-func (t *transaction) writeMeta() error {
+func (t *Transaction) writeMeta() error {
/*
MDB_env *env;
MDB_meta meta, metab, *mp;
@@ -1129,7 +1228,7 @@ func (t *transaction) writeMeta() error {
// @param[out] ret address of a pointer where the page's address will be stored.
// @param[out] lvl dirty_list inheritance level of found page. 1=current txn, 0=mapped page.
// @return 0 on success, non-zero on failure.
-func (t *transaction) getPage(id int) (*page, int, error) {
+func (t *Transaction) getPage(id int) (*page, int, error) {
/*
MDB_env *env = txn->mt_env;
MDB_page *p = NULL;
@@ -1188,7 +1287,7 @@ func (t *transaction) getPage(id int) (*page, int, error) {
// @param[in] leaf The node being read.
// @param[out] data Updated to point to the node's data.
// @return 0 on success, non-zero on failure.
-func (t *transaction) readNode(leaf *node, data []byte) error {
+func (t *Transaction) readNode(leaf *node, data []byte) error {
/*
MDB_page *omp; // overflow page
pgno_t pgno;
@@ -1214,7 +1313,7 @@ func (t *transaction) readNode(leaf *node, data []byte) error {
return nil
}
-func (t *transaction) Get(bucket Bucket, key []byte) ([]byte, error) {
+func (t *Transaction) Get(bucket Bucket, key []byte) ([]byte, error) {
/*
MDB_cursor mc;
MDB_xcursor mx;
@@ -1238,43 +1337,7 @@ func (t *transaction) Get(bucket Bucket, key []byte) ([]byte, error) {
return nil, nil
}
-func (t *transaction) Cursor(b Bucket) (Cursor, error) {
- /*
- MDB_cursor *mc;
- size_t size = sizeof(MDB_cursor);
-
- if (txn == NULL || ret == NULL || dbi >= txn->mt_numdbs || !(txn->mt_dbflags[dbi] & DB_VALID))
- return EINVAL;
-
- if (txn->mt_flags & MDB_TXN_ERROR)
- return MDB_BAD_TXN;
-
- // Allow read access to the freelist
- if (!dbi && !F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
- return EINVAL;
-
- if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT)
- size += sizeof(MDB_xcursor);
-
- if ((mc = malloc(size)) != NULL) {
- mdb_cursor_init(mc, txn, dbi, (MDB_xcursor *)(mc + 1));
- if (txn->mt_cursors) {
- mc->mc_next = txn->mt_cursors[dbi];
- txn->mt_cursors[dbi] = mc;
- mc->mc_flags |= C_UNTRACK;
- }
- } else {
- return ENOMEM;
- }
-
- *ret = mc;
-
- return MDB_SUCCESS;
- */
- return nil, nil
-}
-
-func (t *transaction) Renew1(c Cursor) error {
+func (t *Transaction) Renew1(c Cursor) error {
/*
if (txn == NULL || mc == NULL || mc->mc_dbi >= txn->mt_numdbs)
return EINVAL;
@@ -1288,7 +1351,7 @@ func (t *transaction) Renew1(c Cursor) error {
return nil
}
-func (t *transaction) Delete(b *Bucket, key []byte, data []byte) error {
+func (t *Transaction) Delete(b *Bucket, key []byte, data []byte) error {
/*
MDB_cursor mc;
MDB_xcursor mx;
@@ -1343,7 +1406,7 @@ func (t *transaction) Delete(b *Bucket, key []byte, data []byte) error {
return nil
}
-func (t *transaction) Put(b Bucket, key []byte, data []byte, flags int) error {
+func (t *Transaction) Put(b Bucket, key []byte, data []byte, flags int) error {
/*
MDB_cursor mc;
MDB_xcursor mx;
@@ -1363,7 +1426,7 @@ func (t *transaction) Put(b Bucket, key []byte, data []byte, flags int) error {
return nil
}
-func (t *transaction) Bucket(name string, flags int) (*Bucket, error) {
+func (t *Transaction) Bucket(name string, flags int) (*Bucket, error) {
/*
MDB_val key, data;
MDB_dbi i;
@@ -1467,7 +1530,7 @@ func (t *transaction) Bucket(name string, flags int) (*Bucket, error) {
return nil, nil
}
-func (t *transaction) Stat(b Bucket) *stat {
+func (t *Transaction) Stat(b Bucket) *stat {
/*
if (txn == NULL || arg == NULL || dbi >= txn->mt_numdbs)
return EINVAL;
@@ -1483,7 +1546,7 @@ func (t *transaction) Stat(b Bucket) *stat {
return nil
}
-func (t *transaction) BucketFlags(b Bucket) (int, error) {
+func (t *Transaction) BucketFlags(b Bucket) (int, error) {
/*
// We could return the flags for the FREE_DBI too but what's the point?
if (txn == NULL || dbi < MAIN_DBI || dbi >= txn->mt_numdbs)
@@ -1494,7 +1557,7 @@ func (t *transaction) BucketFlags(b Bucket) (int, error) {
return 0, nil
}
-func (t *transaction) Drop(b *Bucket, del int) error {
+func (t *Transaction) Drop(b *Bucket, del int) error {
/*
MDB_cursor *mc, *m2;
int rc;
generated by cgit v1.2.3 (git 2.50.1) at 2025-07-24 15:49:18 +0000