pgsql: pg_upgrade: Report full disk better

pg_upgrade: Report full disk better

Previously, pg_upgrade would abort copy_file() on a short write without
setting errno, which the caller would report as an error with the
message "Success".  We assume ENOSPC in that case, as we do elsewhere in
the code.  Also set errno in some other error cases in copy_file() to
avoid bogus "Success" error messages.

This was broken in 6b711cf37c228749b6a8cef50e16e3c587d18dd4, so 9.2 and
before are OK.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/bd5a9a50e4946ffc58a632b5717c8cfddd3ea6ce

Modified Files
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contrib/pg_upgrade/file.c |    9 +++++++++
1 file changed, 9 insertions(+)