pgsql: simplehash: Allow use of simplehash without MemoryContext.

simplehash: Allow use of simplehash without MemoryContext.

If the SH_RAW_ALLOCATOR is defined, it will be used to allocate bytes
for the hash table, and no dependencies on MemoryContext will exist.
This means, in particular, that the SH_CREATE function will not take
a MemoryContext argument.

Patch by me, reviewed by Andres Freund.

Discussion: http://postgr.es/m/CA+Tgmob8oyh02NrZW=xCScB+5GyJ-jVowE3+TWTUmPF=FsGWTA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/48995040d5e7b1e9bac35d72aff326cae002219d

Modified Files
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src/include/lib/simplehash.h | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)