Possible Bug in relation_open - Mailing list pgsql-hackers

From Pradeep Kumar
Subject Possible Bug in relation_open
Date
Msg-id CAJ4xhPnTRF09CUAv78gY+jKjbjhK6pobY+n_szMSZnrADtyoNQ@mail.gmail.com
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Responses Re: Possible Bug in relation_open
List pgsql-hackers
Hello Hackers,

If the user tries to open the relation in RangeVar and NoLock mode calling table_openrv(relation, NoLock), it will internally call relation_openrv()-->relation_open(). In relation_open() we checking the Assert(lockmode >= NoLock && lockmode < MAX_LOCKMODES); , here we expecting the lockmode is NoLock or greater than that, but in same function again we checking this assert case Assert(lockmode != NoLock || IsBootstrapProcessingMode() || CheckRelationLockedByMe(r, AccessShareLock, true)); , here we are expecting (lockmode != NoLock) , so why are there two cases that contradict?  and What if the user tries to open the relation in NoLock mode? and that will definitely cause the assert failure, Suppose the user who writes some extension and reads some relation oid that is constant, and wants to acquire NoLock?, need some clarification on this.

Thanks & Regards
Pradeep

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