pgsql: Complain with proper error message if streaming stops prematurel

Complain with proper error message if streaming stops prematurely

In particular, with a controlled shutdown of the master, pg_basebackup
with streaming log could terminate without an error message, even though
the backup is not consistent.

In passing, fix a few cases where walfile wasn't properly set to -1 after
closing.

Fujii Masao

Branch
------
REL9_2_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/0b4660b539821ccdef99e43e79deb023a68db34e

Modified Files
--------------
src/bin/pg_basebackup/receivelog.c |   10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)