ext/dba: end LMDB cursor iteration on write/delete#21979
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| $db = dba_open($db_file, 'cl', 'lmdb'); | ||
| foreach (['a' => '1', 'b' => '2', 'c' => '3'] as $k => $v) { | ||
| dba_replace($k, $v, $db); | ||
| } | ||
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| var_dump(dba_firstkey($db)); | ||
| var_dump(dba_nextkey($db)); |
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Can you have add a test, ideally in a different file, which calls dba_nextkey() immediately after a dob_open?
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Added dba_lmdb_nextkey_without_firstkey.phpt covering dba_nextkey() immediately after open (and again after a dba_replace()), both return false.
dba_insert/replace/delete on an LMDB handler started a write txn into LMDB_IT(txn) while dba_firstkey's cursor was still bound to the read txn in that slot, so the next dba_nextkey renewed a freed handle. Close the cursor and abort the read txn before starting the write txn, and bail out of dba_nextkey when no cursor is open.
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dba_insert/replace/delete on an LMDB handler started a write txn into LMDB_IT(txn) while dba_firstkey's cursor was still bound to the read txn in that slot, so the next dba_nextkey renewed a freed handle. Close the cursor and abort the read txn before starting the write txn, and bail out of dba_nextkey when no cursor is open.