-/* PSPP - computes sample statistics.
- Copyright (C) 2007 Free Software Foundation, Inc.
+/* PSPP - a program for statistical analysis.
+ Copyright (C) 2007, 2009, 2011 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 the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ 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 3 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.
+ 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 General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
-#include <libpspp/taint.h>
+#include "libpspp/taint.h"
#include <stddef.h>
-#include <libpspp/array.h>
-#include <libpspp/assertion.h>
+#include "libpspp/array.h"
+#include "libpspp/assertion.h"
+#include "libpspp/cast.h"
-#include "xalloc.h"
+#include "gl/xalloc.h"
/* This code maintains two invariants:
successor-tainted. */
/* A list of pointers to taint structures. */
-struct taint_list
+struct taint_list
{
- size_t cnt;
+ size_t n;
struct taint **taints;
};
static void taint_list_remove (struct taint_list *, const struct taint *);
/* A taint. */
-struct taint
+struct taint
{
size_t ref_cnt; /* Number of owners. */
struct taint_list successors; /* Successors in graph. */
/* Creates and returns a new taint object. */
struct taint *
-taint_create (void)
+taint_create (void)
{
struct taint *taint = xmalloc (sizeof *taint);
taint->ref_cnt = 1;
they are in fact the same object, but this is not a guarantee
made by the interface.) */
struct taint *
-taint_clone (const struct taint *taint_)
+taint_clone (const struct taint *taint_)
{
- struct taint *taint = (struct taint *) taint_;
+ struct taint *taint = CONST_CAST (struct taint *, taint_);
assert (taint->ref_cnt > 0);
taint->ref_cnt++;
preserve the transitive relationship, so that tainting A will
still taint C. */
bool
-taint_destroy (struct taint *taint)
+taint_destroy (struct taint *taint)
{
- bool was_tainted = taint_is_tainted (taint);
- if (--taint->ref_cnt == 0)
+ if (taint)
{
- size_t i, j;
-
- for (i = 0; i < taint->predecessors.cnt; i++)
- for (j = 0; j < taint->successors.cnt; j++)
- taint_propagate (taint->predecessors.taints[i],
- taint->successors.taints[j]);
-
- for (i = 0; i < taint->predecessors.cnt; i++)
- taint_list_remove (&taint->predecessors.taints[i]->successors, taint);
- for (i = 0; i < taint->successors.cnt; i++)
- taint_list_remove (&taint->successors.taints[i]->predecessors, taint);
-
- taint_list_destroy (&taint->successors);
- taint_list_destroy (&taint->predecessors);
- free (taint);
+ bool was_tainted = taint_is_tainted (taint);
+ if (--taint->ref_cnt == 0)
+ {
+ size_t i, j;
+
+ for (i = 0; i < taint->predecessors.n; i++)
+ for (j = 0; j < taint->successors.n; j++)
+ taint_propagate (taint->predecessors.taints[i],
+ taint->successors.taints[j]);
+
+ for (i = 0; i < taint->predecessors.n; i++)
+ taint_list_remove (&taint->predecessors.taints[i]->successors, taint);
+ for (i = 0; i < taint->successors.n; i++)
+ taint_list_remove (&taint->successors.taints[i]->predecessors, taint);
+
+ taint_list_destroy (&taint->successors);
+ taint_list_destroy (&taint->predecessors);
+ free (taint);
+ }
+ return !was_tainted;
}
- return !was_tainted;
+
+ return true;
}
/* Adds a propagation relationship from FROM to TO. This means
or B will cause the other to be tainted, without producing an
infinite loop. */
void
-taint_propagate (const struct taint *from_, const struct taint *to_)
+taint_propagate (const struct taint *from_, const struct taint *to_)
{
- struct taint *from = (struct taint *) from_;
- struct taint *to = (struct taint *) to_;
-
- if (from != to)
+ struct taint *from = CONST_CAST (struct taint *, from_);
+ struct taint *to = CONST_CAST (struct taint *, to_);
+
+ if (from != to)
{
taint_list_add (&from->successors, to);
taint_list_add (&to->predecessors, from);
if (from->tainted && !to->tainted)
recursively_set_taint (to);
- else if (to->tainted_successor && !from->tainted_successor)
+ else if (to->tainted_successor && !from->tainted_successor)
recursively_set_tainted_successor (from);
}
}
/* Returns true if TAINT is tainted, false otherwise. */
bool
-taint_is_tainted (const struct taint *taint)
+taint_is_tainted (const struct taint *taint)
{
return taint->tainted;
}
/* Marks TAINT tainted and propagates the taint to all of its
successors. */
void
-taint_set_taint (const struct taint *taint_)
+taint_set_taint (const struct taint *taint_)
{
- struct taint *taint = (struct taint *) taint_;
+ struct taint *taint = CONST_CAST (struct taint *, taint_);
if (!taint->tainted)
recursively_set_taint (taint);
}
be reached by following propagation relationships starting
from X.) */
bool
-taint_has_tainted_successor (const struct taint *taint)
+taint_has_tainted_successor (const struct taint *taint)
{
return taint->tainted_successor;
}
/* Attempts to reset the successor-taint on TAINT. This is
successful only if TAINT currently has no tainted successor. */
void
-taint_reset_successor_taint (const struct taint *taint_)
+taint_reset_successor_taint (const struct taint *taint_)
{
- struct taint *taint = (struct taint *) taint_;
+ struct taint *taint = CONST_CAST (struct taint *, taint_);
- if (taint->tainted_successor)
+ if (taint->tainted_successor)
{
size_t i;
- for (i = 0; i < taint->successors.cnt; i++)
+ for (i = 0; i < taint->successors.n; i++)
if (taint->successors.taints[i]->tainted_successor)
return;
\f
/* Initializes LIST as an empty list of taints. */
static void
-taint_list_init (struct taint_list *list)
+taint_list_init (struct taint_list *list)
{
- list->cnt = 0;
+ list->n = 0;
list->taints = NULL;
}
/* Destroys LIST. */
static void
-taint_list_destroy (struct taint_list *list)
+taint_list_destroy (struct taint_list *list)
{
free (list->taints);
}
/* Returns true if TAINT is in LIST, false otherwise. */
static bool
-taint_list_contains (const struct taint_list *list, const struct taint *taint)
+taint_list_contains (const struct taint_list *list, const struct taint *taint)
{
size_t i;
- for (i = 0; i < list->cnt; i++)
+ for (i = 0; i < list->n; i++)
if (list->taints[i] == taint)
return true;
/* Returns true if X is zero or a power of 2, false otherwise. */
static bool
-is_zero_or_power_of_2 (size_t x)
+is_zero_or_power_of_2 (size_t x)
{
return (x & (x - 1)) == 0;
}
/* Adds TAINT to LIST, if it isn't already in the list. */
static void
-taint_list_add (struct taint_list *list, struct taint *taint)
+taint_list_add (struct taint_list *list, struct taint *taint)
{
- if (!taint_list_contains (list, taint))
+ if (!taint_list_contains (list, taint))
{
/* To save a few bytes of memory per list, we don't store
the list capacity as a separate member. Instead, the
list capacity is always zero or a power of 2. Thus, if
the list count is one of these threshold values, we need
to allocate more memory. */
- if (is_zero_or_power_of_2 (list->cnt))
+ if (is_zero_or_power_of_2 (list->n))
list->taints = xnrealloc (list->taints,
- list->cnt == 0 ? 1 : 2 * list->cnt,
+ list->n == 0 ? 1 : 2 * list->n,
sizeof *list->taints);
- list->taints[list->cnt++] = taint;
+ list->taints[list->n++] = taint;
}
}
/* Removes TAINT from LIST (which must contain it). */
static void
-taint_list_remove (struct taint_list *list, const struct taint *taint)
+taint_list_remove (struct taint_list *list, const struct taint *taint)
{
size_t i;
- for (i = 0; i < list->cnt; i++)
+ for (i = 0; i < list->n; i++)
if (list->taints[i] == taint)
{
- remove_element (list->taints, list->cnt, sizeof *list->taints, i);
- list->cnt--;
+ remove_element (list->taints, list->n, sizeof *list->taints, i);
+ list->n--;
return;
}
recursively. Also marks TAINT's predecessors as
successor-tainted, recursively. */
static void
-recursively_set_taint (struct taint *taint)
+recursively_set_taint (struct taint *taint)
{
size_t i;
-
+
taint->tainted = taint->tainted_successor = true;
- for (i = 0; i < taint->successors.cnt; i++)
+ for (i = 0; i < taint->successors.n; i++)
{
struct taint *s = taint->successors.taints[i];
if (!s->tainted)
recursively_set_taint (s);
}
- for (i = 0; i < taint->predecessors.cnt; i++)
+ for (i = 0; i < taint->predecessors.n; i++)
{
struct taint *p = taint->predecessors.taints[i];
if (!p->tainted_successor)
/* Marks TAINT as successor-tainted, as well as all of its
predecessors recursively. */
static void
-recursively_set_tainted_successor (struct taint *taint)
+recursively_set_tainted_successor (struct taint *taint)
{
size_t i;
-
+
taint->tainted_successor = true;
- for (i = 0; i < taint->predecessors.cnt; i++)
+ for (i = 0; i < taint->predecessors.n; i++)
{
struct taint *p = taint->predecessors.taints[i];
if (!p->tainted_successor)