pgsql: Don't cast off_t to 32-bit type for output, bug fix

Don't cast off_t to 32-bit type for output, bug fix

off_t is most likely a 64-bit integer, so casting it to a 32-bit type
for output could lose data. There are more issues like this in the
tree, but this is an instance where this could actually happen in
practice, since base backups are routinely larger than 4 GB. So this
is separated out as a bug fix.

Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: /messages/by-id/20ce62fa-47fc-457b-b504-12f3c1651726@eisentraut.org

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/215ab56119e02ec77b3bd417ccf5334f9259bb52

Modified Files
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src/backend/backup/basebackup_server.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)