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yap-6.3/packages/semweb/atom_map.c

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/* $Id$
Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: wielemak@science.uva.nl
WWW: http://www.swi-prolog.org
Copyright (C): 2006, University of Amsterdam
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <SWI-Stream.h>
#include <SWI-Prolog.h>
#include "avl.h"
#include "lock.h"
#include "atom.h"
#include "debug.h"
#include <string.h>
#include <assert.h>
#ifdef __WINDOWS__
#define inline __inline
#endif
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
This file realises the low-level support for indexing literals in the
semantic web library. The idea is to make a map from abstracted tokens
from each literal to the exact literals. Abstraction introduces a
certain amount of ambiguity that makes fuzzy matching possible. Good
abstraction candidates are the Porter Stem or Snowbal algorithm and the
Double Metaphone algorithm. Both are provide by the SWI-Prolog NLP
package.
Basic query provides a set of abstracted terms and requests those
literals containing all of them. We maintain ordered sets of literals
and do set-intersection on them to achieve good linear performance.
Some current E-culture project statistics (porter stem)
# stems: 0.4 million
# literals: 0.9 million
# stem->literal relations: 3.1 million
Av. literals/stem: about 8.
Searching is done using
rdf_find_literal_map(Map, SetOfAbstract, -Literals)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#define AM_MAGIC 0x6ab19e8e
typedef struct atom_map
{ long magic; /* AM_MAGIC */
size_t value_count; /* total # values */
rwlock lock; /* Multi-threaded access */
avl_tree tree; /* AVL tree */
} atom_map;
typedef void *datum;
#define S_MAGIC 0x8734abcd
typedef struct atom_set
{ size_t size; /* # cells in use */
size_t allocated; /* # cells allocated */
datum *atoms; /* allocated cells */
#ifdef O_SECURE
long magic;
#endif
} atom_set;
#define ND_MAGIC 0x67b49a23
#define ND_MAGIC_EX 0x753ab3c
typedef struct node_data
{ datum key;
atom_set *values;
#ifdef O_SECURE
long magic;
#endif
} node_data;
typedef struct node_data_ex
{ node_data data;
atom_info atom;
#ifdef O_SECURE
long magic;
#endif
} node_data_ex;
#define RDLOCK(map) rdlock(&map->lock)
#define WRLOCK(map, allowreaders) wrlock(&map->lock, allowreaders)
#define LOCKOUT_READERS(map) lockout_readers(&map->lock)
#define REALLOW_READERS(map) reallow_readers(&map->lock)
#define WRUNLOCK(map) unlock(&map->lock, FALSE)
#define RDUNLOCK(map) unlock(&map->lock, TRUE)
/*******************************
* BASIC STUFF *
*******************************/
static functor_t FUNCTOR_error2;
static functor_t FUNCTOR_type_error2;
static functor_t FUNCTOR_domain_error2;
static functor_t FUNCTOR_resource_error1;
static functor_t FUNCTOR_atom_map1;
static functor_t FUNCTOR_size2;
static functor_t FUNCTOR_not1;
static atom_t ATOM_all;
static atom_t ATOM_case;
static atom_t ATOM_prefix;
static atom_t ATOM_le;
static atom_t ATOM_ge;
static atom_t ATOM_between;
static atom_t ATOM_key;
#define MKFUNCTOR(n,a) \
FUNCTOR_ ## n ## a = PL_new_functor(PL_new_atom(#n), a)
#define MKATOM(n) \
ATOM_ ## n = PL_new_atom(#n)
static void
init_functors()
{ FUNCTOR_atom_map1 = PL_new_functor(PL_new_atom("$literal_map"), 1);
MKFUNCTOR(error, 2);
MKFUNCTOR(type_error, 2);
MKFUNCTOR(domain_error, 2);
MKFUNCTOR(resource_error, 1);
MKFUNCTOR(size, 2);
MKFUNCTOR(not, 1);
MKATOM(all);
MKATOM(case);
MKATOM(prefix);
MKATOM(le);
MKATOM(ge);
MKATOM(between);
MKATOM(key);
}
static int
type_error(term_t actual, const char *expected)
{ term_t ex;
if ( (ex = PL_new_term_ref()) &&
PL_unify_term(ex,
PL_FUNCTOR, FUNCTOR_error2,
PL_FUNCTOR, FUNCTOR_type_error2,
PL_CHARS, expected,
PL_TERM, actual,
PL_VARIABLE) )
return PL_raise_exception(ex);
return FALSE;
}
static int
domain_error(term_t actual, const char *expected)
{ term_t ex;
if ( (ex = PL_new_term_ref()) &&
PL_unify_term(ex,
PL_FUNCTOR, FUNCTOR_error2,
PL_FUNCTOR, FUNCTOR_domain_error2,
PL_CHARS, expected,
PL_TERM, actual,
PL_VARIABLE) )
return PL_raise_exception(ex);
return FALSE;
}
static int
resource_error(const char *what)
{ term_t ex;
if ( (ex = PL_new_term_ref()) &&
PL_unify_term(ex,
PL_FUNCTOR, FUNCTOR_error2,
PL_FUNCTOR, FUNCTOR_resource_error1,
PL_CHARS, what,
PL_VARIABLE) )
return PL_raise_exception(ex);
return FALSE;
}
static int
representation_error(const char *what)
{ term_t ex = PL_new_term_ref();
if ( (ex = PL_new_term_ref()) &&
PL_unify_term(ex,
PL_FUNCTOR, FUNCTOR_error2,
PL_FUNCTOR_CHARS, "representation_error", 1,
PL_CHARS, what,
PL_VARIABLE) )
return PL_raise_exception(ex);
return FALSE;
}
static int
get_atom_ex(term_t t, atom_t *a)
{ if ( PL_get_atom(t, a) )
return TRUE;
return type_error(t, "atom");
}
static int
get_long_ex(term_t t, long *v)
{ if ( PL_get_long(t, v) )
return TRUE;
return type_error(t, "integer");
}
static int
get_atom_map(term_t t, atom_map **map)
{ if ( PL_is_functor(t, FUNCTOR_atom_map1) )
{ term_t a = PL_new_term_ref();
void *ptr;
_PL_get_arg(1, t, a);
if ( PL_get_pointer(a, &ptr) )
{ atom_map *am = ptr;
if ( am->magic == AM_MAGIC )
{ *map = am;
return TRUE;
}
}
}
return type_error(t, "atom_map");
}
static int
unify_atom_map(term_t t, atom_map *map)
{ return PL_unify_term(t, PL_FUNCTOR, FUNCTOR_atom_map1,
PL_POINTER, map);
}
/*******************************
* DATUM *
*******************************/
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Datum is either an atom or a 31-bit signed integer. Atoms are shifted 7
bits
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#define ATOM_TAG_BITS 7
#define ATOM_TAG 0x1
#define tag(d) ((long)(d)&0x1)
#define isAtomDatum(d) ((long)(d)&ATOM_TAG)
#define isIntDatum(d) !isAtomDatum(d)
#define MAP_MIN_INT (-(long)(1L<<(sizeof(long)*8 - 1 - 1)))
#define MAP_MAX_INT (-MAP_MIN_INT - 1)
static intptr_t atom_mask;
static void
init_datum_store()
{ atom_t a = PL_new_atom("[]");
atom_mask = a & ((1<<(ATOM_TAG_BITS-1))-1);
}
static inline atom_t
atom_from_datum(datum d)
{ unsigned long v = (unsigned long)d;
atom_t a;
a = ((v&~0x1)<<(ATOM_TAG_BITS-1))|atom_mask;
DEBUG(9, Sdprintf("0x%lx --> %s\n", v, PL_atom_chars(a)));
return a;
}
static inline long
long_from_datum(datum d)
{ long v = (long)d;
return (v>>1);
}
static inline datum
atom_to_datum(atom_t a)
{ uintptr_t v = (a>>(ATOM_TAG_BITS-1))|ATOM_TAG;
SECURE(assert(atom_from_datum((datum)v) == a));
DEBUG(9, Sdprintf("Atom %s --> 0x%lx\n", PL_atom_chars(a), v));
return (datum)v;
}
static inline datum
long_to_datum(long v)
{ return (datum)(v<<1);
}
static int
get_datum(term_t t, datum* d)
{ atom_t a;
long l;
if ( PL_get_atom(t, &a) )
{ *d = atom_to_datum(a);
return TRUE;
} else if ( PL_get_long(t, &l) )
{ if ( l < MAP_MIN_INT || l > MAP_MAX_INT )
return representation_error("integer_range");
*d = long_to_datum(l);
return TRUE;
}
return type_error(t, "atom or integer");
}
static int
get_search_datum(term_t t, node_data_ex *search)
{ atom_t a;
long l;
SECURE(search->magic = ND_MAGIC_EX);
if ( PL_get_atom(t, &a) )
{ search->data.key = atom_to_datum(a);
search->atom.handle = a;
search->atom.resolved = FALSE;
return TRUE;
} else if ( PL_get_long(t, &l) )
{ if ( l < MAP_MIN_INT || l > MAP_MAX_INT )
return representation_error("integer_range");
search->data.key = long_to_datum(l);
return TRUE;
}
return type_error(t, "atom or integer");
}
static int
unify_datum(term_t t, datum d)
{ unsigned long v = (unsigned long)d;
if ( isAtomDatum(v) )
return PL_unify_atom(t, atom_from_datum(d));
else
return PL_unify_integer(t, long_from_datum(d));
}
static void
lock_datum(datum d)
{ unsigned long v = (unsigned long)d;
if ( isAtomDatum(v) )
PL_register_atom(atom_from_datum(d));
}
static void
unlock_datum(datum d)
{ unsigned long v = (unsigned long)d;
if ( isAtomDatum(v) )
PL_unregister_atom(atom_from_datum(d));
}
static const char *
format_datum(datum d, char *buf)
{ static char tmp[20];
if ( isAtomDatum(d) )
return PL_atom_chars(atom_from_datum(d));
if ( !buf )
buf = tmp;
Ssprintf(buf, "%ld", long_from_datum(d));
return buf;
}
/*******************************
* ATOM SETS *
*******************************/
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
A set of atoms (literals) is a sorted array of atom-handles. They are
sorted simply by handle as we are not interested in the value in the
actual atom. Search is implemeted as binary search.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#define AS_INITIAL_SIZE 4
static atom_set *
new_atom_set(datum a0)
{ atom_set *as;
if ( (as = malloc(sizeof(*as))) &&
(as->atoms = malloc(sizeof(datum)*AS_INITIAL_SIZE)) )
{ lock_datum(a0);
as->size = 1;
as->allocated = AS_INITIAL_SIZE;
as->atoms[0] = a0;
SECURE(as->magic = S_MAGIC);
}
return as;
}
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
find_in_atom_set(atom_set *as, datum a) returns a pointer to the
location of the atom or, if the atom isn't there, to the first location
*after* the atom
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
static datum *
find_in_atom_set(atom_set *as, datum a, int *found)
{ const datum *ap = (const datum *)as->atoms;
const datum *ep = &ap[as->size];
SECURE(assert(as->magic == S_MAGIC));
for(;;)
{ const datum *cp = ap+(ep-ap)/2;
if ( a < *cp )
{ if ( ep == cp )
{ *found = FALSE;
return (datum*)cp;
}
ep = cp;
} else if ( a > *cp )
{ if ( ap == cp )
{ cp++;
*found = FALSE;
return (datum*)cp;
}
ap = cp;
} else
{ *found = TRUE;
return (datum*)cp;
}
}
}
static int
in_atom_set(atom_set *as, datum a)
{ int found;
find_in_atom_set(as, a, &found);
return found;
}
#define ptr_diff(p1, p2) ((char *)(p1) - (char *)(p2))
static int
insert_atom_set(atom_set *as, datum a)
{ int found;
datum *ap = find_in_atom_set(as, a, &found);
if ( !found )
{ lock_datum(a);
if ( as->size == as->allocated )
{ datum *na;
size_t newsize = as->allocated*2;
if ( !(na = realloc(as->atoms, sizeof(datum)*newsize)) )
return -1;
ap += na-as->atoms;
as->atoms = na;
as->allocated = newsize;
}
assert(as->size < as->allocated);
memmove(ap+1, ap, ptr_diff(&as->atoms[as->size], ap));
as->size++;
*ap = a;
return 1;
}
return 0;
}
static int
delete_atom_set(atom_set *as, datum a)
{ int found;
datum *ap = find_in_atom_set(as, a, &found);
if ( found )
{ unlock_datum(a);
as->size--;
memmove(ap, ap+1, ptr_diff(&as->atoms[as->size], ap));
}
return found;
}
static void
destroy_atom_set(atom_set *as)
{ size_t i;
for(i=0; i<as->size; i++)
unlock_datum(as->atoms[i]);
free(as->atoms);
free(as);
}
static void
free_node_data(void *ptr)
{ node_data *data = ptr;
DEBUG(2,
char b[20];
Sdprintf("Destroying node with key = %s\n",
format_datum(data->key, b)));
unlock_datum(data->key);
destroy_atom_set(data->values);
}
/*******************************
* TREE INTERFACE *
*******************************/
static int
cmp_node_data(void *l, void *r, NODE type)
{ node_data_ex *e1 = l;
node_data *n2 = r;
datum *d1 = e1->data.key;
datum *d2 = n2->key;
int d;
SECURE(assert(e1->magic == ND_MAGIC_EX));
if ( (d=(tag(d1)-tag(d2))) == 0 )
{ if ( isAtomDatum(d1) )
{ return cmp_atom_info(&e1->atom, atom_from_datum(d2));
} else
{ long l1 = long_from_datum(d1);
long l2 = long_from_datum(d2);
return l1 > l2 ? 1 : l1 < l2 ? -1 : 0;
}
}
return d;
}
static void
init_tree_map(atom_map *m)
{ avlinit(&m->tree,
NULL, sizeof(node_data),
cmp_node_data,
free_node_data, /* destroy */
NULL, /* alloc */
NULL); /* free */
}
static foreign_t
new_atom_map(term_t handle)
{ atom_map *m;
if ( !(m=malloc(sizeof(*m))) )
return resource_error("memory");
memset(m, 0, sizeof(*m));
init_lock(&m->lock);
init_tree_map(m);
m->magic = AM_MAGIC;
return unify_atom_map(handle, m);
}
static foreign_t
destroy_atom_map(term_t handle)
{ atom_map *m;
if ( !get_atom_map(handle, &m) )
return FALSE;
WRLOCK(m, FALSE);
avlfree(&m->tree);
m->magic = 0;
WRUNLOCK(m);
destroy_lock(&m->lock);
free(m);
return TRUE;
}
/*******************************
* INSERT *
*******************************/
static foreign_t
insert_atom_map4(term_t handle, term_t from, term_t to, term_t keys)
{ atom_map *map;
datum a2;
node_data_ex search;
node_data *data;
if ( !get_atom_map(handle, &map) ||
!get_search_datum(from, &search) ||
!get_datum(to, &a2) )
return FALSE;
if ( !WRLOCK(map, FALSE) )
return FALSE;
if ( (data=avlfind(&map->tree, &search)) )
{ int rc;
SECURE(assert(data->magic == ND_MAGIC));
if ( (rc=insert_atom_set(data->values, a2)) < 0 )
return resource_error("memory");
if ( rc )
map->value_count++;
} else
{ if ( keys && !PL_unify_integer(keys, map->tree.count+1) )
{ WRUNLOCK(map);
return FALSE;
}
if ( !(search.data.values = new_atom_set(a2)) )
return resource_error("memory");
lock_datum(search.data.key);
SECURE(search.magic = ND_MAGIC);
data = avlins(&map->tree, &search);
assert(!data);
map->value_count++;
}
WRUNLOCK(map);
return TRUE;
}
static foreign_t
insert_atom_map3(term_t handle, term_t from, term_t to)
{ return insert_atom_map4(handle, from, to, 0);
}
/*******************************
* DELETE *
*******************************/
static foreign_t
delete_atom_map2(term_t handle, term_t from)
{ atom_map *map;
node_data_ex search;
node_data *data;
if ( !get_atom_map(handle, &map) ||
!get_search_datum(from, &search) )
return FALSE;
if ( !WRLOCK(map, TRUE) )
return FALSE;
/* TBD: Single pass? */
if ( (data = avlfind(&map->tree, &search)) )
{ LOCKOUT_READERS(map);
map->value_count -= data->values->size;
search.data = *data;
avldel(&map->tree, &search);
REALLOW_READERS(map);
}
WRUNLOCK(map);
return TRUE;
}
static foreign_t
delete_atom_map3(term_t handle, term_t from, term_t to)
{ atom_map *map;
node_data_ex search;
node_data *data;
datum a2;
if ( !get_atom_map(handle, &map) ||
!get_search_datum(from, &search) ||
!get_datum(to, &a2) )
return FALSE;
if ( !WRLOCK(map, TRUE) )
return FALSE;
if ( (data = avlfind(&map->tree, &search)) &&
in_atom_set(data->values, a2) )
{ atom_set *as = data->values;
LOCKOUT_READERS(map);
if ( delete_atom_set(as, a2) )
{ map->value_count--;
if ( as->size == 0 )
{ search.data = *data;
avldel(&map->tree, &search);
}
}
REALLOW_READERS(map);
}
WRUNLOCK(map);
return TRUE;
}
/*******************************
* SEARCH *
*******************************/
typedef struct
{ atom_set *set;
int neg; /* not(Lit) */
} pn_set;
static int
cmp_atom_set_size(const void *p1, const void *p2)
{ const pn_set *ap1 = p1;
const pn_set *ap2 = p2;
if ( ap1->neg != ap2->neg )
return ap1->neg ? 1 : -1; /* all negatives at the end */
return ap1->set->size == ap2->set->size ? 0 :
ap1->set->size < ap2->set->size ? -1 : 1;
}
#define MAX_SETS 100
static foreign_t
find_atom_map(term_t handle, term_t keys, term_t literals)
{ atom_map *map;
pn_set as[MAX_SETS]; /* TBD */
int ns = 0;
term_t tmp = PL_new_term_ref();
term_t tail = PL_copy_term_ref(keys);
term_t head = PL_new_term_ref();
atom_set *s0;
size_t ca;
if ( !get_atom_map(handle, &map) )
return FALSE;
if ( !RDLOCK(map) )
return FALSE;
while(PL_get_list(tail, head, tail))
{ node_data *data;
node_data_ex search;
int neg = FALSE;
if ( PL_is_functor(head, FUNCTOR_not1) )
{ _PL_get_arg(1, head, tmp);
if ( !get_search_datum(tmp, &search) )
goto failure;
neg = TRUE;
} else
{ if ( !get_search_datum(head, &search) )
goto failure;
}
if ( (data = avlfind(&map->tree, &search)) )
{ if ( ns+1 >= MAX_SETS )
return resource_error("max_search_atoms");
as[ns].set = data->values;
as[ns].neg = neg;
DEBUG(2, Sdprintf("Found atom-set of size %d\n", as[ns].set->size));
ns++;
} else if ( !neg )
{ RDUNLOCK(map); /* failure on positive literal: empty */
return PL_unify_nil(literals);
}
}
if ( !PL_get_nil(tail) )
{ type_error(tail, "list");
goto failure;
}
qsort(as, ns, sizeof(*as), cmp_atom_set_size);
if ( ns==0 || as[0].neg )
{ domain_error(keys, "keywords");
goto failure;
}
s0 = as[0].set;
PL_put_term(tail, literals);
for(ca=0; ca<s0->size; ca++)
{ datum a = s0->atoms[ca];
int i;
for(i=1; i<ns; i++)
{ if ( !as[i].neg )
{ if ( !in_atom_set(as[i].set, a) )
{ if ( a > as[i].set->atoms[as[i].set->size-1] )
goto empty;
goto next;
}
} else
{ if ( in_atom_set(as[i].set, a) )
goto next;
}
}
if ( !PL_unify_list(tail, head, tail) ||
!unify_datum(head, a) )
goto failure;
next:;
}
empty:
RDUNLOCK(map);
return PL_unify_nil(tail);
failure:
RDUNLOCK(map);
return FALSE;
}
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
rdf_keys_in_literal_map(+Map, +Spec, -Keys)
Spec is one of
* all
* prefix(Text) atoms only
* ge(Low) integers only
* le(High)
* between(Low, High)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* TBD: should use avlwalk(), but this isn't fine as it does not allow a
failure return and does not allow passing our term-handles
*/
static int
unify_keys(term_t head, term_t tail, AVLnode *node)
{ node_data *data;
if ( node )
{ if ( node->subtree[LEFT] )
{ if ( !unify_keys(head, tail, node->subtree[LEFT]) )
return FALSE;
}
data = (node_data*)node->data;
if ( !PL_unify_list(tail, head, tail) ||
!unify_datum(head, data->key) )
return FALSE;
if ( node->subtree[RIGHT] )
return unify_keys(head, tail, node->subtree[RIGHT]);
}
return TRUE;
}
static int
between_keys(atom_map *map, long min, long max, term_t head, term_t tail)
{ avl_enum state;
node_data *data;
node_data_ex search;
DEBUG(2, Sdprintf("between %ld .. %ld\n", min, max));
search.data.key = long_to_datum(min);
SECURE(search.magic = ND_MAGIC_EX);
if ( (data = avlfindfirst(&map->tree, &search, &state)) &&
isIntDatum(data->key) )
{ for(;;)
{ if ( long_from_datum(data->key) > max )
break;
if ( !PL_unify_list(tail, head, tail) ||
!unify_datum(head, data->key) )
{ avlfinddestroy(&state);
return FALSE;
}
if ( !(data = avlfindnext(&state)) ||
!isIntDatum(data->key) )
break;
}
avlfinddestroy(&state);
}
return TRUE;
}
static foreign_t
rdf_keys_in_literal_map(term_t handle, term_t spec, term_t keys)
{ atom_map *map;
term_t tail = PL_copy_term_ref(keys);
term_t head = PL_new_term_ref();
atom_t name;
int arity;
if ( !get_atom_map(handle, &map) )
return FALSE;
if ( !RDLOCK(map) )
return FALSE;
if ( !PL_get_name_arity(spec, &name, &arity) )
type_error(spec, "key-specifier");
if ( name == ATOM_all )
{ AVLnode *node = map->tree.root;
if ( !unify_keys(head, tail, node) )
goto failure;
} else if ( name == ATOM_key && arity == 1 )
{ term_t a = PL_new_term_ref();
node_data *data;
node_data_ex search;
_PL_get_arg(1, spec, a);
if ( !get_search_datum(a, &search) )
goto failure;
if ( (data = avlfind(&map->tree, &search)) )
{ long size = (long)data->values->size;
RDUNLOCK(map);
assert(size > 0);
return PL_unify_integer(keys, size);
}
goto failure;
} else if ( (name == ATOM_prefix || name == ATOM_case) && arity == 1 )
{ term_t a = PL_new_term_ref();
atom_t prefix, first_a;
avl_enum state;
node_data *data;
node_data_ex search;
int match = (name == ATOM_prefix ? STR_MATCH_PREFIX : STR_MATCH_EXACT);
_PL_get_arg(1, spec, a);
if ( !get_atom_ex(a, &prefix) )
goto failure;
first_a = first_atom(prefix, STR_MATCH_PREFIX);
search.data.key = atom_to_datum(first_a);
search.atom.handle = first_a;
search.atom.resolved = FALSE;
SECURE(search.magic = ND_MAGIC_EX);
for(data = avlfindfirst(&map->tree, &search, &state);
data;
data=avlfindnext(&state))
{ assert(isAtomDatum(data->key));
if ( !match_atoms(match,
first_a, atom_from_datum(data->key)) )
break;
if ( !PL_unify_list(tail, head, tail) ||
!unify_datum(head, data->key) )
{ avlfinddestroy(&state);
goto failure;
}
}
avlfinddestroy(&state);
} else if ( (name == ATOM_ge || name == ATOM_le) && arity == 1 )
{ term_t a = PL_new_term_ref();
long val, min, max;
_PL_get_arg(1, spec, a);
if ( !get_long_ex(a, &val) )
goto failure;
if ( name == ATOM_ge )
min = val, max = MAP_MAX_INT;
else
max = val, min = MAP_MIN_INT;
if ( !between_keys(map, min, max, head, tail) )
goto failure;
} else if ( name == ATOM_between && arity == 2 )
{ term_t a = PL_new_term_ref();
long min, max;
_PL_get_arg(1, spec, a);
if ( !get_long_ex(a, &min) )
goto failure;
_PL_get_arg(2, spec, a);
if ( !get_long_ex(a, &max) )
goto failure;
if ( !between_keys(map, min, max, head, tail) )
goto failure;
} else
{ type_error(spec, "key-specifier");
goto failure;
}
RDUNLOCK(map);
return PL_unify_nil(tail);
failure:
RDUNLOCK(map);
return FALSE;
}
/*******************************
* RESET *
*******************************/
static foreign_t
rdf_reset_literal_map(term_t handle)
{ atom_map *map;
if ( !get_atom_map(handle, &map) )
return FALSE;
if ( !WRLOCK(map, FALSE) )
return FALSE;
avlfree(&map->tree);
init_tree_map(map);
map->value_count = 0;
WRUNLOCK(map);
return TRUE;
}
/*******************************
* STATISTICS *
*******************************/
term_t
rdf_statistics_literal_map(term_t map, term_t key)
{ atom_map *m;
if ( !get_atom_map(map, &m) )
return FALSE;
if ( PL_is_functor(key, FUNCTOR_size2) )
{ term_t a = PL_new_term_ref();
_PL_get_arg(1, key, a);
if ( !PL_unify_integer(a, m->tree.count) )
return FALSE;
_PL_get_arg(2, key, a);
return PL_unify_integer(a, m->value_count);
}
return type_error(key, "statistics_key");
}
/*******************************
* REGISTER *
*******************************/
#define PRED(n,a,f,o) PL_register_foreign(n,a,f,o)
install_t
install_atom_map()
{ init_functors();
init_datum_store();
PRED("rdf_new_literal_map", 1, new_atom_map, 0);
PRED("rdf_destroy_literal_map", 1, destroy_atom_map, 0);
PRED("rdf_reset_literal_map", 1, rdf_reset_literal_map, 0);
PRED("rdf_insert_literal_map", 3, insert_atom_map3, 0);
PRED("rdf_insert_literal_map", 4, insert_atom_map4, 0);
PRED("rdf_delete_literal_map", 3, delete_atom_map3, 0);
PRED("rdf_delete_literal_map", 2, delete_atom_map2, 0);
PRED("rdf_find_literal_map", 3, find_atom_map, 0);
PRED("rdf_keys_in_literal_map", 3, rdf_keys_in_literal_map, 0);
PRED("rdf_statistics_literal_map", 2, rdf_statistics_literal_map, 0);
}