pgsql: Forbid invalid combination of options in pg_basebackup.

Forbid invalid combination of options in pg_basebackup.

Commit 56c7d8d4552180fd66fe48423bb2a9bb767c2d87 allowed pg_basebackup
to stream WAL in tar mode. But there is the restriction that WAL
streaming in tar mode works only when the value - (dash) is not
specified as output directory. This means that the combination of
three options "-D -", "-F t" and "-X stream" is invalid. However,
previously, even when those options were specified at the same time,
pg_basebackup background process unexpectedly started streaming WAL.
And then it exited with an error.

This commit changes pg_basebackup so that it errors out on such
invalid combination of options at the beginning.

Reviewed by Magnus Hagander, and patch by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ecbdc4c555f43b1ac284c734752b00c2ea6f277b

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c | 10 ++++++++++
1 file changed, 10 insertions(+)