[pgpool-committers: 49] pgpool: Allow health check retry while connect(). It is reported that

[Tatsuo Ishii]

Allow health check retry while connect().  It is reported that
connect() blocks sigalarm under some conditions, for example:
> When system is configured for security reasons not to return destination
> host unreachable messages ([pgpool-general: 131])

To enable this, following changes have been made. Part of changes are
contributed by Stevo Slavic.

- Make health_check_timer_expired to be global variable. This is set
  when alarm is timed out in health checking process. The variable is
  refered to by lower level functions such as
  connect_inet_domain_socket_by_port().

- Modify connect_inet_domain_socket_by_port() so that it calls
  connect(2) with non block socket. This allows to detect
  health_check_timer_expired flag be set while retrying.

- Add retry parameter to make_persistent_db_connection(). The flag is
  passed to connect_inet_domain_socket_by_port(). Retry = false is
  used by health_check().

- Change pool_read2 etc. not to trigger failover if reading from
  socket fails when fail_over_on_backend_error = off. Before
  fail_over_on_backend_error is only refered to by socket writing
  functions. But treating reading functions so is more consistent.

Branch
------
master

Details
-------
http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=3d3fe8611b8a87e8787fc50272c59e40b28daff4

Modified Files
--------------
child.c                         |    8 ++++----
doc/pgpool-en.html              |    9 ++++-----
main.c                          |   28 ++++++++++++++++++++++------
pgpool.conf.sample              |    4 +---
pgpool.conf.sample-master-slave |    4 +---
pgpool.conf.sample-replication  |    4 +---
pgpool.conf.sample-stream       |    4 +---
pool.h                          |    6 ++----
pool_connection_pool.c          |   20 ++++++++++++++++++--
pool_stream.c                   |   24 +++++++++++++++++-------
pool_worker_child.c             |    2 +-
11 files changed, 72 insertions(+), 41 deletions(-)