pgsql: Avoid including tablespaces inside PGDATA twice in base backups

Avoid including tablespaces inside PGDATA twice in base backups

If a tablespace was crated inside PGDATA it was backed up both as part
of the PGDATA backup and as the backup of the tablespace. Avoid this
by skipping any directory inside PGDATA that contains one of the active
tablespaces.

Dimitri Fontaine and Magnus Hagander

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/2edf3e82c5e23bf9095cab5c7c19578d46a13e48

Modified Files
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src/backend/replication/basebackup.c |   60 ++++++++++++++++++++++++++++++----
1 file changed, 53 insertions(+), 7 deletions(-)