[pgpool-committers: 8337] pgpool: Fix long standing bug with pcp_node_info.

[Tatsuo Ishii]

Fix long standing bug with pcp_node_info.

It appears that occasionally pcp_node_info shows backend_status field
as "quarantine" when it should be "down". While pcp_node_info shows
the status, first it checks the backend_status member in BackendInfo
struct. If it is 3, then checks quarantine member. If it is other than
0, then the backend_status field is shown as "quarantine". So if
garbage remains in quarantine member, it is shown as "quarantine". The
BackendInfo struct is transferred from pcp_worker process to pcp
frontend client. Unfortunately when the quarantine member was added by
commit 54af632c, it was forgotten to modify pcp_worker.c and
pcp_frontend.c so that the "quarantine" member is transferred.

Fix is needed to be back patched to 3.7, when the "quarantine" member
was first added.

Discussion: https://www.pgpool.net/pipermail/pgpool-hackers/2022-January/004110.html

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=da2b7f134e4cf4aadb751f1fb8ad405c79292fbb

Modified Files
--------------
src/libs/pcp/pcp.c       | 8 +++++++-
src/pcp_con/pcp_worker.c | 6 +++++-
2 files changed, 12 insertions(+), 2 deletions(-)