From d6968e625770d021c8db15094ea732b40be2c5aa Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Fri, 21 Aug 2015 14:36:54 -0300 Subject: [PATCH] Do not allow *timestamp to be passed as NULL The code had bugs that would cause crashes if NULL was passed as that argument (originally intended to mean not to bother returning its value), and after inspection it turns out that nothing seems interested in the case that *ts is NULL anyway. Therefore, remove the partial checks intended to support that case. Author: Michael Paquier though I didn't include a proposed Assert. Backpatch to 9.5. --- src/backend/access/transam/commit_ts.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/src/backend/access/transam/commit_ts.c b/src/backend/access/transam/commit_ts.c index 5ad35c0d7f..33136e3c1d 100644 --- a/src/backend/access/transam/commit_ts.c +++ b/src/backend/access/transam/commit_ts.c @@ -252,8 +252,10 @@ TransactionIdSetCommitTs(TransactionId xid, TimestampTz ts, /* * Interrogate the commit timestamp of a transaction. * - * Return value indicates whether commit timestamp record was found for - * given xid. + * The return value indicates whether a commit timestamp record was found for + * the given xid. The timestamp value is returned in *ts (which may not be + * null), and the origin node for the Xid is returned in *nodeid, if it's not + * null. */ bool TransactionIdGetCommitTsData(TransactionId xid, TimestampTz *ts, @@ -294,8 +296,7 @@ TransactionIdGetCommitTsData(TransactionId xid, TimestampTz *ts, TransactionIdPrecedes(xid, oldestCommitTs) || TransactionIdPrecedes(newestCommitTs, xid)) { - if (ts) - *ts = 0; + *ts = 0; if (nodeid) *nodeid = InvalidRepOriginId; return false; @@ -312,8 +313,7 @@ TransactionIdGetCommitTsData(TransactionId xid, TimestampTz *ts, LWLockAcquire(CommitTsLock, LW_SHARED); if (commitTsShared->xidLastCommit == xid) { - if (ts) - *ts = commitTsShared->dataLastCommit.time; + *ts = commitTsShared->dataLastCommit.time; if (nodeid) *nodeid = commitTsShared->dataLastCommit.nodeid; @@ -330,8 +330,7 @@ TransactionIdGetCommitTsData(TransactionId xid, TimestampTz *ts, SizeOfCommitTimestampEntry * entryno, SizeOfCommitTimestampEntry); - if (ts) - *ts = entry.time; + *ts = entry.time; if (nodeid) *nodeid = entry.nodeid;