/* PSPP - a program for statistical analysis.
- Copyright (C) 1997-9, 2000, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1997-9, 2000, 2009, 2010 Free Software Foundation, Inc.
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
#include <libpspp/compiler.h>
#include <libpspp/hash-functions.h>
#include <libpspp/hmap.h>
+#include <libpspp/intern.h>
#include <libpspp/message.h>
#include <libpspp/str.h>
#include "xalloc.h"
-static struct atom *atom_create (const char *string);
-static void atom_destroy (struct atom *);
-static const char *atom_to_string (const struct atom *);
-
-/* Returns the label in VL. The caller must not modify or free
- the returned value. */
-const char *
-val_lab_get_label (const struct val_lab *vl)
-{
- return atom_to_string (vl->label);
-}
-
/* Creates and returns a new, empty set of value labels with the
given WIDTH. */
struct val_labs *
copy = val_labs_create (vls->width);
HMAP_FOR_EACH (label, struct val_lab, node, &vls->labels)
- val_labs_add (copy, &label->value, atom_to_string (label->label));
+ val_labs_add (copy, &label->value, label->label);
return copy;
}
{
hmap_delete (&vls->labels, &label->node);
value_destroy (&label->value, vls->width);
- atom_destroy (label->label);
+ intern_unref (label->label);
free (label);
}
}
+/* Returns the width of VLS. */
+int
+val_labs_get_width (const struct val_labs *vls)
+{
+ return vls->width;
+}
+
/* Returns the number of value labels in VLS.
Returns 0 if VLS is null. */
size_t
const char *label)
{
struct val_lab *lab = xmalloc (sizeof *lab);
- value_init (&lab->value, vls->width);
- value_copy (&lab->value, value, vls->width);
- lab->label = atom_create (label);
+ value_clone (&lab->value, value, vls->width);
+ lab->label = intern_new (label);
hmap_insert (&vls->labels, &lab->node, value_hash (value, vls->width, 0));
}
struct val_lab *vl = val_labs_lookup (vls, value);
if (vl != NULL)
{
- atom_destroy (vl->label);
- vl->label = atom_create (label);
+ intern_unref (vl->label);
+ vl->label = intern_new (label);
}
else
do_add_val_lab (vls, value, label);
{
hmap_delete (&vls->labels, &label->node);
value_destroy (&label->value, vls->width);
- atom_destroy (label->label);
+ intern_unref (label->label);
free (label);
}
val_labs_find (const struct val_labs *vls, const union value *value)
{
const struct val_lab *label = val_labs_lookup (vls, value);
- return label ? atom_to_string (label->label) : NULL;
+ return label ? label->label : NULL;
}
/* Searches VLS for a value label for VALUE. If successful,
else
return NULL;
}
-\f
-/* Atoms: reference-counted constant strings. */
-
-/* An atom. */
-struct atom
- {
- struct hmap_node node; /* Hash map node. */
- char *string; /* String value. */
- unsigned ref_count; /* Number of references. */
- };
-
-/* Hash table of atoms. */
-static struct hmap atoms = HMAP_INITIALIZER (atoms);
-
-static void free_atom (struct atom *atom);
-static void free_all_atoms (void);
-
-/* Creates and returns an atom for STRING. */
-static struct atom *
-atom_create (const char *string)
-{
- static bool initialized;
- struct atom *atom;
- size_t hash;
-
- assert (string != NULL);
-
- if (!initialized)
- {
- initialized = true;
- atexit (free_all_atoms);
- }
-
- hash = hash_string (string, 0);
- HMAP_FOR_EACH_WITH_HASH (atom, struct atom, node, hash, &atoms)
- if (!strcmp (atom->string, string))
- {
- atom->ref_count++;
- return atom;
- }
-
- atom = xmalloc (sizeof *atom);
- atom->string = xstrdup (string);
- atom->ref_count = 1;
- hmap_insert (&atoms, &atom->node, hash);
- return atom;
-}
-
-/* Destroys ATOM. */
-static void
-atom_destroy (struct atom *atom)
-{
- if (atom != NULL)
- {
- assert (atom->ref_count > 0);
- atom->ref_count--;
- if (atom->ref_count == 0)
- {
- hmap_delete (&atoms, &atom->node);
- free_atom (atom);
- }
- }
-}
-
-/* Returns the string associated with ATOM. */
-static const char *
-atom_to_string (const struct atom *atom)
-{
- return atom->string;
-}
-
-static void
-free_atom (struct atom *atom)
-{
- free (atom->string);
- free (atom);
-}
-
-static void
-free_all_atoms (void)
-{
- struct atom *atom, *next;
-
- HMAP_FOR_EACH_SAFE (atom, next, struct atom, node, &atoms)
- free_atom (atom);
-}