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CREATE TABLE dir (
id SERIAL PRIMARY KEY,
parent_id INTEGER REFERENCES dir( id ),
name TEXT,
path TEXT,
UNIQUE( name, parent_id ),
UNIQUE( path ),
size INTEGER DEFAULT 0,
mode INTEGER NOT NULL DEFAULT 0,
uid INTEGER NOT NULL DEFAULT 0,
gid INTEGER NOT NULL DEFAULT 0,
ref_count INTEGER NOT NULL DEFAULT 0,
ctime TIMESTAMP,
mtime TIMESTAMP,
atime TIMESTAMP
);
-- TODO: 512 is STANDARD_BLOCK_SIZE in config.h, must be in sync!
CREATE TABLE data (
id SERIAL PRIMARY KEY,
dir_id INTEGER,
block_no INTEGER NOT NULL DEFAULT 0,
FOREIGN KEY( dir_id ) REFERENCES dir( id ),
data BYTEA NOT NULL DEFAULT repeat(E'\\000',512)::bytea
);
-- create indexes for fast data access
CREATE INDEX data_dir_id_idx ON data( dir_id );
CREATE INDEX data_block_no_idx ON data( block_no );
-- create an index on the parent_id for
-- directory listings
CREATE INDEX dir_parent_id_idx ON dir( parent_id );
-- 16384 == S_IFDIR (S_IFDIR)
-- TODO: should be created by the program after checking the OS
-- it is running on (for full POSIX compatibility)
-- make sure 'dir' entries always get a first block in the 'data'
-- table
CREATE OR REPLACE RULE "dir_insert" AS ON
INSERT TO dir WHERE NEW.mode & 16384 = 0
DO ALSO INSERT INTO data( dir_id )
VALUES ( currval( 'dir_id_seq' ) );
-- garbage collect deleted file entries, delete all blocks in 'data'
CREATE OR REPLACE RULE "dir_remove" AS ON
DELETE TO dir WHERE OLD.mode & 16384 = 0
DO ALSO DELETE FROM data WHERE dir_id=OLD.id;
-- self-referencing anchor for root directory
-- 16895 = S_IFDIR and 0777 permissions
-- TODO: should be done from outside, see note above
INSERT INTO dir( id, parent_id, name, path, size, mode, uid, gid, ctime, mtime, atime )
VALUES( 0, 0, '/', '/', 0, 16895, 0, 0, NOW( ), NOW( ), NOW( ) );
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