[pgpool-committers: 1972] pgpool: Fix unportable code related to SO_REUSEPORT.

[Tatsuo Ishii]

Fix unportable code related to SO_REUSEPORT.

There are several places using setsockopt(sock, SOL_SOCKET,
SO_REUSEPORT...). SO_REUSEPORT is not available on all Linux kernels
and the source code uses ifdef to detect the feature in the compile
time. Problem is, the binary created with kernel which provides the
feature cannot run on a kernel which does not provide the feature. Fix
is, detecting the feature in the run time by checking error code
returned by setsockopt() and ignore it if the cause of the error is
lacking the feature.

Branch
------
V3_3_STABLE

Details
-------
http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=62e3b91bcf436489cebb4c76ede0507f90c36854

Modified Files
--------------
watchdog/wd_heartbeat.c |   65 +++++++++++++++++++++++++++++++----------------
1 file changed, 43 insertions(+), 22 deletions(-)