C++ -> C : Module for converting the WHERE clause to the canonical form with PostgreSQL

Help me, please,
i have a module, which converts the WHERE clause to a canonical form, i.e. converting a logical clause to a conjuntional or dicjuntional clauses. For example:

(ves > 100 or bbbb = 10) AND (bbbb = aaa + 1 OR (aaaa AND caa))

will be converted to dicjuntional form:

ves>100 AND bbbb=10 AND bbbb=aaa+1 OR вес>100 AND bbbb=10 AND aaaa OR ves>100
AND bbbb=10 AND caa

That module is writen in the C++ langguage, how can i connect it to the PostgreSQL sources? In our project we must to compare queries. Beacause of the same query can be writen in different forms, so to compare queries we must to convert them to the same form of presentation.

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stvalentine