+/* PSPP - computes sample statistics.
+ Copyright (C) 2007 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 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. */
+
+/* This is a test program for the routines defined in tower.c.
+ This test program aims to be as comprehensive as possible.
+ With -DNDEBUG, "gcov -b" should report 100% coverage of lines
+ and branches in tower.c routines. (Without -DNDEBUG, branches
+ caused by failed assertions will not be taken.) "valgrind
+ --leak-check=yes --show-reachable=yes" should give a clean
+ report, both with and without -DNDEBUG. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <libpspp/tower.h>
+
+#include <assert.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libpspp/compiler.h>
+
+#include "xalloc.h"
+\f
+/* Currently running test. */
+static const char *test_name;
+
+/* Exit with a failure code.
+ (Place a breakpoint on this function while debugging.) */
+static void
+check_die (void)
+{
+ exit (EXIT_FAILURE);
+}
+
+/* If OK is not true, prints a message about failure on the
+ current source file and the given LINE and terminates. */
+static void
+check_func (bool ok, int line)
+{
+ if (!ok)
+ {
+ printf ("Check failed in %s test at %s, line %d\n",
+ test_name, __FILE__, line);
+ check_die ();
+ }
+}
+
+/* Verifies that EXPR evaluates to true.
+ If not, prints a message citing the calling line number and
+ terminates. */
+#define check(EXPR) check_func ((EXPR), __LINE__)
+\f
+/* Node type and support routines. */
+
+/* Test data block. */
+struct block
+ {
+ struct tower_node node; /* Embedded tower block. */
+ int x; /* Primary value. */
+ };
+
+/* Returns the `struct block' that NODE is embedded within. */
+static struct block *
+tower_node_to_block (const struct tower_node *node)
+{
+ return tower_data (node, struct block, node);
+}
+
+/* Swaps *A and *B. */
+static void
+swap (int *a, int *b)
+{
+ int t = *a;
+ *a = *b;
+ *b = t;
+}
+
+/* Reverses the order of the CNT integers starting at VALUES. */
+static void
+reverse (int *values, size_t cnt)
+{
+ size_t i = 0;
+ size_t j = cnt;
+
+ while (j > i)
+ swap (&values[i++], &values[--j]);
+}
+
+/* Arranges the CNT blocks in VALUES into the lexicographically
+ next greater permutation. Returns true if successful.
+ If VALUES is already the lexicographically greatest
+ permutation of its blocks (i.e. ordered from greatest to
+ smallest), arranges them into the lexicographically least
+ permutation (i.e. ordered from smallest to largest) and
+ returns false. */
+static bool
+next_permutation (int *values, size_t cnt)
+{
+ if (cnt > 0)
+ {
+ size_t i = cnt - 1;
+ while (i != 0)
+ {
+ i--;
+ if (values[i] < values[i + 1])
+ {
+ size_t j;
+ for (j = cnt - 1; values[i] >= values[j]; j--)
+ continue;
+ swap (values + i, values + j);
+ reverse (values + (i + 1), cnt - (i + 1));
+ return true;
+ }
+ }
+
+ reverse (values, cnt);
+ }
+
+ return false;
+}
+
+/* Returns N!. */
+static unsigned int
+factorial (unsigned int n)
+{
+ unsigned int value = 1;
+ /* Disallow N values that overflow on 32-bit machines. */
+ assert (n <= 12);
+ for (; n > 1; )
+ value *= n--;
+ return value;
+}
+
+/* Returns C(n, k), the number of ways that K choices can be made
+ from N items when order is unimportant. */
+static unsigned int
+binomial_cofficient (unsigned int n, unsigned int k)
+{
+ assert (n >= k);
+ return factorial (n) / factorial (k) / factorial (n - k);
+}
+
+/* Tests whether PARTS is a K-part integer composition of N.
+ Returns true if so, false otherwise. */
+static bool UNUSED
+is_k_composition (int n, int k, const int parts[])
+{
+ int sum;
+ int i;
+
+ sum = 0;
+ for (i = 0; i < k; i++)
+ {
+ if (parts[i] < 1 || parts[i] > n)
+ return false;
+ sum += parts[i];
+ }
+ return sum == n;
+}
+
+/* Advances the K-part integer composition of N stored in PARTS
+ to the next lexicographically greater one.
+ Returns true if successful, false if the composition was
+ already the greatest K-part composition of N (in which case
+ PARTS is unaltered). */
+static bool
+next_k_composition (int n UNUSED, int k, int parts[])
+{
+ int x, i;
+
+ assert (is_k_composition (n, k, parts));
+ if (k == 1)
+ return false;
+
+ for (i = k - 1; i > 0; i--)
+ if (parts[i] > 1)
+ break;
+ if (i == 0)
+ return false;
+
+ x = parts[i] - 1;
+ parts[i] = 1;
+ parts[i - 1]++;
+ parts[k - 1] = x;
+
+ assert (is_k_composition (n, k, parts));
+ return true;
+}
+
+/* Sets the K integers in PARTS to the lexicographically first
+ K-part composition of N. */
+static void
+first_k_composition (int n, int k, int parts[])
+{
+ int i;
+
+ assert (n >= k);
+
+ for (i = 0; i < k; i++)
+ parts[i] = 1;
+ parts[k - 1] += n - k;
+}
+
+/* Advances *K and PARTS to the next integer composition of N.
+ Compositions are ordered from shortest to longest and in
+ lexicographical order within a given length.
+ Before the first call, initialize *K to 0.
+ After each successful call, *K contains the length of the
+ current composition and the *K blocks in PARTS contain its
+ parts.
+ Returns true if successful, false if the set of compositions
+ has been exhausted. */
+static bool
+next_composition (int n, int *k, int parts[])
+{
+ if (*k >= 1 && next_k_composition (n, *k, parts))
+ return true;
+ else if (*k < n)
+ {
+ first_k_composition (n, ++*k, parts);
+ return true;
+ }
+ else
+ return false;
+}
+
+/* A block expected to be found in a tower. */
+struct expected_block
+ {
+ int height; /* Expected height of bottom of block. */
+ int x; /* Expected value for `x' member. */
+ };
+
+/* Checks that tower T contains the BLOCK_CNT blocks described by
+ BLOCKS[]. */
+static void
+check_tower (struct tower *t,
+ struct expected_block blocks[], size_t block_cnt)
+{
+ int total_height;
+ struct tower_node *node;
+ size_t i;
+
+ check (tower_is_empty (t) == (block_cnt == 0));
+
+ total_height = 0;
+ for (i = 0; i < block_cnt; i++)
+ {
+ unsigned long int level;
+ for (level = total_height;
+ level < total_height + blocks[i].height;
+ level++)
+ {
+ struct tower_node *found;
+ unsigned long int block_start;
+ found = tower_lookup (t, level, &block_start);
+ check (found != NULL);
+ check (tower_node_to_block (found)->x == blocks[i].x);
+ check (block_start == total_height);
+ }
+ total_height += blocks[i].height;
+ }
+ check (tower_height (t) == total_height);
+
+ for (node = tower_first (t), i = 0;
+ node != NULL;
+ node = tower_next (t, node), i++)
+ {
+ check (tower_node_get_height (node) == blocks[i].height);
+ check (tower_node_to_block (node)->x == blocks[i].x);
+ }
+ check (i == block_cnt);
+}
+\f
+/* Tests inserting all possible sets of block heights into a
+ tower in all possible orders, up to a specified maximum tower
+ height. */
+static void
+test_insert (void)
+{
+ const int max_height = 7;
+ int cnt;
+
+ for (cnt = 1; cnt <= max_height; cnt++)
+ {
+ unsigned int composition_cnt;
+ struct expected_block *expected;
+ int *heights;
+ int block_cnt;
+ int *order;
+ struct block *blocks;
+
+ expected = xnmalloc (cnt, sizeof *expected);
+ heights = xnmalloc (cnt, sizeof *heights);
+ order = xnmalloc (cnt, sizeof *order);
+ blocks = xnmalloc (cnt, sizeof *blocks);
+
+ block_cnt = 0;
+ composition_cnt = 0;
+ while (next_composition (cnt, &block_cnt, heights))
+ {
+ int i, j;
+ unsigned int permutation_cnt;
+
+ for (i = 0; i < block_cnt; i++)
+ order[i] = i;
+
+ permutation_cnt = 0;
+ while (permutation_cnt == 0 || next_permutation (order, block_cnt))
+ {
+ struct tower t;
+
+ /* Inserts the block_cnt blocks with the given
+ heights[] into T in the order given by order[]. */
+ tower_init (&t);
+ for (i = 0; i < block_cnt; i++)
+ {
+ struct block *under;
+ int idx;
+
+ idx = order[i];
+ blocks[idx].x = idx;
+
+ under = NULL;
+ for (j = 0; j < i; j++)
+ if (idx < order[j]
+ && (under == NULL || under->x > order[j]))
+ under = &blocks[order[j]];
+
+ tower_insert (&t, heights[idx], &blocks[idx].node,
+ under != NULL ? &under->node : NULL);
+ }
+
+ /* Check that the result is what we expect. */
+ for (i = 0; i < block_cnt; i++)
+ {
+ expected[i].height = heights[i];
+ expected[i].x = i;
+ }
+ check_tower (&t, expected, block_cnt);
+
+ permutation_cnt++;
+ }
+ check (permutation_cnt == factorial (block_cnt));
+
+ composition_cnt++;
+ }
+ check (composition_cnt == 1 << (cnt - 1));
+
+ free (expected);
+ free (heights);
+ free (order);
+ free (blocks);
+ }
+}
+
+/* Tests deleting blocks from towers that initially contain all
+ possible sets of block heights into a tower in all possible
+ orders, up to a specified maximum tower height. */
+static void
+test_delete (void)
+{
+ const int max_height = 7;
+ int cnt;
+
+ for (cnt = 1; cnt <= max_height; cnt++)
+ {
+ unsigned int composition_cnt;
+ struct expected_block *expected;
+ int *heights;
+ int block_cnt;
+ int *order;
+ struct block *blocks;
+
+ expected = xnmalloc (cnt, sizeof *expected);
+ heights = xnmalloc (cnt, sizeof *heights);
+ order = xnmalloc (cnt, sizeof *order);
+ blocks = xnmalloc (cnt, sizeof *blocks);
+
+ block_cnt = 0;
+ composition_cnt = 0;
+ while (next_composition (cnt, &block_cnt, heights))
+ {
+ int i;
+ unsigned int permutation_cnt;
+
+ for (i = 0; i < block_cnt; i++)
+ order[i] = i;
+
+ permutation_cnt = 0;
+ while (permutation_cnt == 0 || next_permutation (order, block_cnt))
+ {
+ struct tower t;
+
+ /* Insert blocks into tower in ascending order. */
+ tower_init (&t);
+ for (i = 0; i < block_cnt; i++)
+ {
+ blocks[i].x = i;
+ tower_insert (&t, heights[i], &blocks[i].node, NULL);
+ expected[i].x = i;
+ expected[i].height = heights[i];
+ }
+ check_tower (&t, expected, block_cnt);
+
+ /* Delete blocks from tower in the order of
+ order[]. */
+ for (i = 0; i < block_cnt; i++)
+ {
+ int idx = order[i];
+ int j;
+ tower_delete (&t, &blocks[idx].node);
+ for (j = 0; ; j++)
+ {
+ assert (j < block_cnt - i);
+ if (expected[j].x == idx)
+ {
+ memcpy (&expected[j], &expected[j + 1],
+ sizeof *expected * (block_cnt - i - j - 1));
+ break;
+ }
+ }
+ check_tower (&t, expected, block_cnt - i - 1);
+ }
+
+ permutation_cnt++;
+ }
+ check (permutation_cnt == factorial (block_cnt));
+
+ composition_cnt++;
+ }
+ check (composition_cnt == 1 << (cnt - 1));
+
+ free (expected);
+ free (heights);
+ free (order);
+ free (blocks);
+ }
+}
+
+/* Tests towers containing all possible block heights, resizing
+ the blocks to all possible heights that conserve the total
+ tower height, up to a maximum total tower height. */
+static void
+test_resize (void)
+{
+ const int max_height = 9;
+ int cnt;
+
+ for (cnt = 1; cnt <= max_height; cnt++)
+ {
+ unsigned int composition_cnt;
+ struct expected_block *expected;
+ int *heights, *new_heights;
+ int block_cnt;
+ int *order;
+ struct block *blocks;
+
+ expected = xnmalloc (cnt, sizeof *expected);
+ heights = xnmalloc (cnt, sizeof *heights);
+ new_heights = xnmalloc (cnt, sizeof *new_heights);
+ order = xnmalloc (cnt, sizeof *order);
+ blocks = xnmalloc (cnt, sizeof *blocks);
+
+ block_cnt = 0;
+ composition_cnt = 0;
+ while (next_composition (cnt, &block_cnt, heights))
+ {
+ int i;
+ unsigned int resizes = 0;
+
+ for (resizes = 0, first_k_composition (cnt, block_cnt, new_heights);
+ (resizes == 0
+ || next_k_composition (cnt, block_cnt, new_heights));
+ resizes++)
+ {
+ struct tower t;
+
+ /* Insert blocks into tower in ascending order. */
+ tower_init (&t);
+ for (i = 0; i < block_cnt; i++)
+ {
+ blocks[i].x = i;
+ tower_insert (&t, heights[i], &blocks[i].node, NULL);
+ expected[i].x = i;
+ expected[i].height = heights[i];
+ }
+ check_tower (&t, expected, block_cnt);
+
+ /* Resize all the blocks. */
+ for (i = 0; i < block_cnt; i++)
+ {
+ if (expected[i].height != new_heights[i] || rand () % 2)
+ tower_resize (&t, &blocks[i].node, new_heights[i]);
+ expected[i].height = new_heights[i];
+ }
+ check_tower (&t, expected, block_cnt);
+ }
+ check (resizes == binomial_cofficient (cnt - 1, block_cnt - 1));
+
+ composition_cnt++;
+ }
+ check (composition_cnt == 1 << (cnt - 1));
+
+ free (expected);
+ free (new_heights);
+ free (heights);
+ free (order);
+ free (blocks);
+ }
+}
+
+/* Tests splicing all possible contiguous sets of blocks out of one
+ tower into a second, initially empty tower. */
+static void
+test_splice_out (void)
+{
+ const int max_height = 9;
+ int cnt;
+
+ for (cnt = 1; cnt <= max_height; cnt++)
+ {
+ unsigned int composition_cnt;
+ struct expected_block *expected;
+ int *heights, *new_heights;
+ int block_cnt;
+ int *order;
+ struct block *blocks;
+
+ expected = xnmalloc (cnt, sizeof *expected);
+ heights = xnmalloc (cnt, sizeof *heights);
+ new_heights = xnmalloc (cnt, sizeof *new_heights);
+ order = xnmalloc (cnt, sizeof *order);
+ blocks = xnmalloc (cnt, sizeof *blocks);
+
+ block_cnt = 0;
+ composition_cnt = 0;
+ while (next_composition (cnt, &block_cnt, heights))
+ {
+ int i, j;
+
+ for (i = 0; i < block_cnt; i++)
+ for (j = i; j <= block_cnt; j++)
+ {
+ struct tower src, dst;
+ int k;
+
+ tower_init (&src);
+ tower_init (&dst);
+
+ /* Insert blocks into SRC and DST in ascending order. */
+ for (k = 0; k < block_cnt; k++)
+ {
+ blocks[k].x = k;
+ tower_insert (&src, heights[k], &blocks[k].node, NULL);
+ expected[k].x = k;
+ expected[k].height = heights[k];
+ }
+ check_tower (&src, expected, block_cnt);
+
+ /* Splice blocks I...J into DST. */
+ tower_splice (&dst, NULL, &src, &blocks[i].node,
+ j < block_cnt ? &blocks[j].node : NULL);
+ check_tower (&dst, &expected[i], j - i);
+ memmove (&expected[i], &expected[j],
+ sizeof *expected * (block_cnt - j));
+ check_tower (&src, expected, block_cnt - (j - i));
+ }
+ composition_cnt++;
+ }
+ check (composition_cnt == 1 << (cnt - 1));
+
+ free (expected);
+ free (new_heights);
+ free (heights);
+ free (order);
+ free (blocks);
+ }
+}
+
+/* Tests splicing all of the contents of a tower into all
+ possible positions in a second tower. */
+static void
+test_splice_in (void)
+{
+ const int max_height = 9;
+ int cnt;
+
+ for (cnt = 1; cnt <= max_height; cnt++)
+ {
+ unsigned int composition_cnt;
+ struct expected_block *expected;
+ int *heights, *new_heights;
+ int block_cnt;
+ int *order;
+ struct block *blocks;
+
+ expected = xnmalloc (cnt, sizeof *expected);
+ heights = xnmalloc (cnt, sizeof *heights);
+ new_heights = xnmalloc (cnt, sizeof *new_heights);
+ order = xnmalloc (cnt, sizeof *order);
+ blocks = xnmalloc (cnt, sizeof *blocks);
+
+ block_cnt = 0;
+ composition_cnt = 0;
+ while (next_composition (cnt, &block_cnt, heights))
+ {
+ int i, j;
+
+ for (i = 0; i < block_cnt; i++)
+ for (j = i; j <= block_cnt; j++)
+ {
+ struct tower src, dst;
+ int k;
+
+ tower_init (&src);
+ tower_init (&dst);
+
+ /* Insert blocks into SRC and DST in ascending order. */
+ for (k = 0; k < block_cnt; k++)
+ {
+ blocks[k].x = k;
+ tower_insert (k >= i && k < j ? &src : &dst,
+ heights[k], &blocks[k].node, NULL);
+ expected[k].x = k;
+ expected[k].height = heights[k];
+ }
+
+ /* Splice SRC into DST. */
+ tower_splice (&dst, j < block_cnt ? &blocks[j].node : NULL,
+ &src, i != j ? &blocks[i].node : NULL, NULL);
+ check_tower (&dst, expected, block_cnt);
+ }
+ composition_cnt++;
+ }
+ check (composition_cnt == 1 << (cnt - 1));
+
+ free (expected);
+ free (new_heights);
+ free (heights);
+ free (order);
+ free (blocks);
+ }
+}
+
+\f
+/* Main program. */
+
+/* Runs TEST_FUNCTION and prints a message about NAME. */
+static void
+run_test (void (*test_function) (void), const char *name)
+{
+ test_name = name;
+ putchar ('.');
+ fflush (stdout);
+ test_function ();
+}
+
+int
+main (void)
+{
+ run_test (test_insert, "insert");
+ run_test (test_delete, "delete");
+ run_test (test_resize, "resize");
+ run_test (test_splice_out, "splice out");
+ run_test (test_splice_in, "splice in");
+ putchar ('\n');
+
+ return 0;
+}