pgsql: walreceiver: tweak pg_stat_wal_receiver behavior

walreceiver: tweak pg_stat_wal_receiver behavior

There are two problems in the original coding: one is that if one
walreceiver process exits, the ready_to_display flag remains set in
shared memory, exposing the conninfo of the next walreceiver before
obfuscating. Fix by having WalRcvDie reset the flag.

Second, the sleep-and-retry behavior that waited until walreceiver had
set ready_to_display wasn't liked; the preference is to have it return
no data instead, so let's do that.

Bugs in 9ed551e0a reported by Fujii Masao and Michël Paquier.

Author: Michaël Paquier

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1bdae16fca884a9190dc330790e7a63c04989fa3

Modified Files
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src/backend/replication/walreceiver.c | 22 ++++++----------------
1 file changed, 6 insertions(+), 16 deletions(-)