pgsql: Rework handling of OOM when allocating record buffer in XLOG rea

Rework handling of OOM when allocating record buffer in XLOG reader.

Commit 2c03216 changed allocate_recordbuf() so that it uses a palloc to
allocate the read buffer and fails immediately when an out-of-memory error
shows up, even though its callers still expect that NULL is returned in that
case. This bug is fixed making allocate_recordbuf() use a palloc_extended
with MCXT_ALLOC_NO_OOM flag and return NULL in OOM case.

Michael Paquier

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9b8d4782ba0f75eb0f029c743bb85166999d9fa5

Modified Files
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src/backend/access/transam/xlogreader.c |    8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)