libei/src/util-list.c
Peter Hutterer 974df9b5ce util: add a list_nth_entry() macro
Returns the nth element for a given list. Note that unlike the other
macros, this takes a type, not a variable as first argument.

Signed-off-by:Peter Hutterer <peter.hutterer@who-t.net>
2021-07-22 13:09:39 +10:00

192 lines
4.4 KiB
C

/*
* Copyright © 2008-2011 Kristian Høgsberg
* Copyright © 2011 Intel Corporation
* Copyright © 2013-2015 Red Hat, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include "config.h"
#include <assert.h>
#include <stddef.h>
#include <stdbool.h>
#include "util-list.h"
void
list_init(struct list *list)
{
list->prev = list;
list->next = list;
}
void
list_insert(struct list *list, struct list *elm)
{
assert((list->next != NULL && list->prev != NULL) ||
!"list->next|prev is NULL, possibly missing list_init()");
assert(((elm->next == NULL && elm->prev == NULL) || list_empty(elm)) ||
!"elm->next|prev is not NULL, list node used twice?");
elm->prev = list;
elm->next = list->next;
list->next = elm;
elm->next->prev = elm;
}
void
list_append(struct list *list, struct list *elm)
{
assert((list->next != NULL && list->prev != NULL) ||
!"list->next|prev is NULL, possibly missing list_init()");
assert(((elm->next == NULL && elm->prev == NULL) || list_empty(elm)) ||
!"elm->next|prev is not NULL, list node used twice?");
elm->next = list;
elm->prev = list->prev;
list->prev = elm;
elm->prev->next = elm;
}
void
list_remove(struct list *elm)
{
assert((elm->next != NULL && elm->prev != NULL) ||
!"list->next|prev is NULL, possibly missing list_init()");
elm->prev->next = elm->next;
elm->next->prev = elm->prev;
elm->next = NULL;
elm->prev = NULL;
}
bool
list_empty(const struct list *list)
{
assert((list->next != NULL && list->prev != NULL) ||
!"list->next|prev is NULL, possibly missing list_init()");
return list->next == list;
}
#if _enable_tests_
#include "util-munit.h"
#include "util-macros.h"
MUNIT_TEST(test_list_insert)
{
struct list_test {
int val;
struct list node;
} tests[] = {
{ .val = 1 },
{ .val = 2 },
{ .val = 3 },
{ .val = 4 },
};
struct list_test *t;
struct list head;
list_init(&head);
munit_assert(list_empty(&head));
ARRAY_FOR_EACH(tests, t) {
list_insert(&head, &t->node);
}
int val = 4;
list_for_each(t, &head, node) {
munit_assert_int(t->val, ==, val);
val--;
}
munit_assert_int(val, ==, 0);
return MUNIT_OK;
}
MUNIT_TEST(test_list_append)
{
struct list_test {
int val;
struct list node;
} tests[] = {
{ .val = 1 },
{ .val = 2 },
{ .val = 3 },
{ .val = 4 },
};
struct list_test *t;
struct list head;
list_init(&head);
munit_assert(list_empty(&head));
ARRAY_FOR_EACH(tests, t) {
list_append(&head, &t->node);
}
int val = 1;
list_for_each(t, &head, node) {
munit_assert_int(t->val, ==, val);
val++;
}
munit_assert_int(val, ==, 5);
return MUNIT_OK;
}
MUNIT_TEST(test_list_nth)
{
struct list_test {
int val;
struct list node;
} tests[] = {
{ .val = 1 },
{ .val = 2 },
{ .val = 3 },
{ .val = 4 },
};
struct list_test *t;
struct list head;
list_init(&head);
ARRAY_FOR_EACH(tests, t) {
list_append(&head, &t->node);
}
int idx = 0;
ARRAY_FOR_EACH(tests, t) {
struct list_test *nth = list_nth_entry(struct list_test,
&head, node, idx);
munit_assert_int(nth->val, ==, tests[idx].val);
idx++;
}
munit_assert(list_nth_entry(struct list_test, &head, node, 10) == NULL);
list_init(&head);
munit_assert(list_nth_entry(struct list_test, &head, node, 0) == NULL);
munit_assert(list_nth_entry(struct list_test, &head, node, 1) == NULL);
return MUNIT_OK;
}
#endif