[pgpool-committers: 877] pgpool: Add interlocking mechanism of exclusive failover command execut

[Yugo Nagata]

Add interlocking mechanism of exclusive failover command execution

When using multiple pgpools with watchdog enabled, failover commands
(failover_command, failback_command, and follow_master_comman) get
executed only at one pgpool.

Previously, these command got executed at all pgpools.

Branch
------
feature/watchdog_for_v3_3

Details
-------
http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=89eabdd8e78c945da144be92aeca9afa7c51981b

Modified Files
--------------
Makefile.in             |   68 +-
aclocal.m4              | 7877 +----------------------------------------------
configure               |   22 +-
main.c                  |  100 +-
parser/Makefile.in      |    7 +-
pcp/Makefile.in         |    7 +-
watchdog/Makefile.am    |    3 +-
watchdog/Makefile.in    |   16 +-
watchdog/watchdog.c     |    9 +-
watchdog/watchdog.h     |   87 +-
watchdog/wd_child.c     |   77 +-
watchdog/wd_ext.h       |   23 +-
watchdog/wd_init.c      |    9 +-
watchdog/wd_lifecheck.c |    2 +-
watchdog/wd_list.c      |  135 +-
watchdog/wd_packet.c    |  136 +-
watchdog/wd_udp.c       |   29 +-
17 files changed, 593 insertions(+), 8014 deletions(-)