Thread: pgsql: Fix error message on short read of pg_control

Fix error message on short read of pg_control

Instead of saying "error: success", indicate that we got a working read
but it was too short.

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/29ce50091d128faaabd0a4044e91a7d0da11bb8e

Modified Files
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src/backend/access/transam/xlog.c | 16 ++++++++++++----
src/common/controldata_utils.c    | 35 ++++++++++++++++++++++++++---------
2 files changed, 38 insertions(+), 13 deletions(-)