1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2021 FUJITSU LIMITED. All rights reserved.
4 * Author: Yang Xu <xuyang2018.jy@fujitsu.com>
5 */
6
7/*\
8 * [Description]
9 *
10 * Test whether the file offset are the same for both file descriptors.
11 */
12
13#include <errno.h>
14#include <stdio.h>
15#include <unistd.h>
16#include "tst_test.h"
17#include "tst_safe_macros.h"
18
19#define WRITE_STR "abcdefg"
20
21static int ofd = -1, nfd = 10;
22
23static struct tcase {
24	off_t offset;
25	size_t exp_size;
26	/* 0 - change offset before dup2, 1 - change offset after dup2 */
27	int flag;
28	char *exp_data;
29	char *desc;
30} tcases[] = {
31	{1, 6, 0, "bcdefg", "Test offset with lseek before dup2"},
32	{2, 5, 1, "cdefg", "Test offset with lseek after dup2"},
33};
34
35static void setup(void)
36{
37	ofd = SAFE_OPEN("testfile", O_RDWR | O_CREAT, 0644);
38	SAFE_WRITE(SAFE_WRITE_ALL, ofd, WRITE_STR, sizeof(WRITE_STR) - 1);
39}
40
41static void cleanup(void)
42{
43	if (ofd > 0)
44		SAFE_CLOSE(ofd);
45	close(nfd);
46}
47
48static void run(unsigned int i)
49{
50	struct tcase *tc = tcases + i;
51	char read_buf[20];
52
53	memset(read_buf, 0, sizeof(read_buf));
54
55	tst_res(TINFO, "%s", tc->desc);
56	if (!tc->flag)
57		SAFE_LSEEK(ofd, tc->offset, SEEK_SET);
58
59	TEST(dup2(ofd, nfd));
60	if (TST_RET == -1) {
61		tst_res(TFAIL | TTERRNO, "call failed unexpectedly");
62		return;
63	}
64	if (tc->flag)
65		SAFE_LSEEK(ofd, tc->offset, SEEK_SET);
66
67	SAFE_READ(1, nfd, read_buf, tc->exp_size);
68	if (strncmp(read_buf, tc->exp_data, tc->exp_size))
69		tst_res(TFAIL, "Expect %s, but get %s.", tc->exp_data, read_buf);
70	else
71		tst_res(TPASS, "Get expected buf %s", read_buf);
72}
73
74static struct tst_test test = {
75	.needs_tmpdir = 1,
76	.tcnt = ARRAY_SIZE(tcases),
77	.test = run,
78	.setup = setup,
79	.cleanup = cleanup,
80};
81