-- $Id$

-- I/O functions.

CREATE FUNCTION sig_in(cstring) RETURNS sig
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_in' LANGUAGE 'C';

CREATE FUNCTION sig_in(int4) RETURNS sig
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_in_int4' LANGUAGE 'C';

CREATE FUNCTION sig_in(int4[]) RETURNS sig
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_in_int4arr' LANGUAGE 'C';

CREATE FUNCTION sig_out(sig) RETURNS cstring
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_out' LANGUAGE 'C';

-- INTERNALLENGTH = 64 bits / 8 = 8 bytes.

CREATE TYPE sig (
  INTERNALLENGTH = 8,
  INPUT = sig_in,
  OUTPUT = sig_out
);

-- Bit functions.

CREATE FUNCTION sig_complement(sig) RETURNS sig
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_complement' LANGUAGE 'C' STRICT;

CREATE FUNCTION sig_union(sig, sig) RETURNS sig
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_union' LANGUAGE 'C' STRICT;

CREATE OPERATOR ~ (
  RIGHTARG = sig,
  PROCEDURE = sig_complement
);

CREATE OPERATOR ^ (
  LEFTARG = sig,
  RIGHTARG = sig,
  PROCEDURE = sig_union,
  COMMUTATOR = ^
);

-- Relations.

CREATE FUNCTION sig_equals(sig, sig) RETURNS boolean
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_equals' LANGUAGE 'C' STRICT;

CREATE FUNCTION sig_subset(sig, sig) RETURNS boolean
AS '/home/zukerman/d/pg/sig/sig', 'pg_sig_subset' LANGUAGE 'C' STRICT;

CREATE FUNCTION sig_superset(sig, sig) RETURNS boolean
AS 'SELECT sig_subset($2,$1);' LANGUAGE 'sql' STRICT;

CREATE OPERATOR ~= (
  LEFTARG = sig,
  RIGHTARG = sig,
  PROCEDURE = sig_equals,
  COMMUTATOR = ~=,
  RESTRICT = eqsel,
  JOIN = eqjoinsel
);

CREATE OPERATOR ~<= (
  LEFTARG = sig,
  RIGHTARG = sig,
  PROCEDURE = sig_subset,
  COMMUTATOR = ~>=,
  RESTRICT = contsel,
  JOIN = contjoinsel
);

CREATE OPERATOR ~>= (
  LEFTARG = sig,
  RIGHTARG = sig,
  PROCEDURE = sig_superset,
  COMMUTATOR = ~<=,
  RESTRICT = contsel,
  JOIN = contjoinsel
);

-- GiST definitions.

CREATE FUNCTION g_sig_consistent(internal, internal, int2) RETURNS bool
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_union(bytea, internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_compress(internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_decompress(internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_penalty(internal, internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_picksplit(bytea, internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE FUNCTION g_sig_same(internal, internal, internal) RETURNS internal
AS '/home/zukerman/d/pg/sig/sig' LANGUAGE 'C';

CREATE OPERATOR CLASS sig_ops
FOR TYPE sig USING gist AS
  OPERATOR 6 ~=,
  OPERATOR 7 ~>=,
  FUNCTION 1 g_sig_consistent (internal, internal, int2),
  FUNCTION 2 g_sig_union (bytea, internal),
  FUNCTION 3 g_sig_compress (internal),
  FUNCTION 4 g_sig_decompress (internal),
  FUNCTION 5 g_sig_penalty (internal, internal),
  FUNCTION 6 g_sig_picksplit (bytea, internal),
  FUNCTION 7 g_sig_same (internal, internal, internal);

--

CREATE TABLE x (y sig);
CREATE INDEX xx ON x USING gist (y sig_ops);