Thread: pgsql: pg_upgrade: check for clean server shutdowns

pg_upgrade:  check for clean server shutdowns

Previously pg_upgrade checked for the pid file and started/stopped the
server to force a clean shutdown.  However, "pg_ctl -m immediate"
removes the pid file but doesn't do a clean shutdown, so check
pg_controldata for a clean shutdown too.

Diagnosed-by: Vimalraj A

Discussion: https://postgr.es/m/CAFKBAK5e4Q-oTUuPPJ56EU_d2Rzodq6GWKS3ncAk3xo7hAsOZg@mail.gmail.com

Backpatch-through: 9.3

Branch
------
REL9_3_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/a5c84e0b7f38ebc5115591d7b0d4ddc706d21c41

Modified Files
--------------
contrib/pg_upgrade/controldata.c | 59 ++++++++++++++++++++++++++++++++++++++++
contrib/pg_upgrade/pg_upgrade.c  |  3 +-
2 files changed, 61 insertions(+), 1 deletion(-)