[pgpool-committers: 1692] pgpool: Fix a segmentation fault in parallel mode with system_db_hostna

[Yugo Nagata]

Fix a segmentation fault in parallel mode with system_db_hostname is empty

When system_db_hostname is empty, unix domain socket should be used.
However, the directory containing the socket file was't specified in this
case, and the initialization of system DB connection failed. This caused
segmentation fault, when processing a query to system db.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=be536d8a283f8799ff67d285b7a3e2e629d8c83f

Modified Files
--------------
doc/pgpool-en.html       |    8 +-
doc/pgpool-ja.html       |    5 +-
src/config/pool_config.c | 1445 ++++++++++++++++++++--------------------------
src/config/pool_config.l |   41 +-
4 files changed, 670 insertions(+), 829 deletions(-)