[pgpool-committers: 2461] pgpool: Fix to set SIGCHLD to SIG_DFL instead of SIG_IGN in watchdog pr

[Yugo Nagata]

Fix to set SIGCHLD to SIG_DFL instead of SIG_IGN in watchdog processes

When using waitpid, it isn't necessary to set SIGCHLD SIG_IGN. Rather,
waitpid returns ECHLD and WIFEXITED could be zero even when the child
process exit successfully. Due to this, it was recognized that ping
exited abnormally in error.

In addition, signal functions are replaced to pool_singal.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=63ea8f20d5e994d8d81a42786a62cd5868acbfc3

Modified Files
--------------
src/watchdog/watchdog.c     |   13 ++++++-------
src/watchdog/wd_child.c     |   19 +++++++++----------
src/watchdog/wd_heartbeat.c |   37 ++++++++++++++++++-------------------
src/watchdog/wd_if.c        |    8 +-------
src/watchdog/wd_lifecheck.c |    1 -
src/watchdog/wd_ping.c      |    2 +-
6 files changed, 35 insertions(+), 45 deletions(-)