[pgpool-committers: 6336] pgpool: Fix health check time out.

[Tatsuo Ishii]

Fix health check time out.

Heal check time out could happen in several places:

1) connect system call
2) select system call
3) read system call

1) was ok but in 2) and 3) it was possible that it could go into
infinite loop in Pgpool-II 3.7 or later. This was due to a mistake
when health check process was modified to be separate process in 3.7,
and back patched to 3.7 and above.

Discussion:
https://www.pgpool.net/pipermail/pgpool-hackers/2019-October/003458.html
https://www.pgpool.net/pipermail/pgpool-hackers/2019-October/003459.html

Branch
------
V4_0_STABLE

Details
-------
https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=1d87df78835f975606ce247f2b60f22b99d04c6e

Modified Files
--------------
src/protocol/pool_process_query.c | 4 ++--
src/utils/pool_stream.c           | 7 +++++++
2 files changed, 9 insertions(+), 2 deletions(-)