xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/pwritev/pwritev01.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2015 Fujitsu Ltd.
4  * Author: Xiao Yang <[email protected]>
5  * Copyright (c) Linux Test Project, 2016-2023
6  */
7 
8 /*\
9  * [Description]
10  *
11  * Testcase to check the basic functionality of the pwritev(2).
12  *
13  * pwritev(2) should succeed to write the expected content of data
14  * and after writing the file, the file offset is not changed.
15  */
16 
17 #define _GNU_SOURCE
18 #include <string.h>
19 #include <sys/uio.h>
20 #include "tst_test.h"
21 #include "pwritev.h"
22 #include "tst_safe_prw.h"
23 
24 #define	CHUNK		64
25 
26 static char buf[CHUNK];
27 static char initbuf[CHUNK * 2];
28 static char preadbuf[CHUNK];
29 static int fd;
30 
31 static struct iovec wr_iovec[] = {
32 	{buf, CHUNK},
33 	{NULL, 0},
34 };
35 
36 static struct tcase {
37 	int count;
38 	off_t offset;
39 	ssize_t size;
40 } tcases[] = {
41 	{1, 0, CHUNK},
42 	{2, 0, CHUNK},
43 	{1, CHUNK/2, CHUNK},
44 };
45 
verify_pwritev(unsigned int n)46 static void verify_pwritev(unsigned int n)
47 {
48 	int i;
49 	struct tcase *tc = &tcases[n];
50 
51 	SAFE_PWRITE(1, fd, initbuf, sizeof(initbuf), 0);
52 
53 	SAFE_LSEEK(fd, 0, SEEK_SET);
54 
55 	TEST(pwritev(fd, wr_iovec, tc->count, tc->offset));
56 	if (TST_RET < 0) {
57 		tst_res(TFAIL | TTERRNO, "pwritev() failed");
58 		return;
59 	}
60 
61 	if (TST_RET != tc->size) {
62 		tst_res(TFAIL, "pwritev() wrote %li bytes, expected %zi",
63 			 TST_RET, tc->size);
64 		return;
65 	}
66 
67 	if (SAFE_LSEEK(fd, 0, SEEK_CUR) != 0) {
68 		tst_res(TFAIL, "pwritev() had changed file offset");
69 		return;
70 	}
71 
72 	SAFE_PREAD(1, fd, preadbuf, tc->size, tc->offset);
73 
74 	for (i = 0; i < tc->size; i++) {
75 		if (preadbuf[i] != 0x61)
76 			break;
77 	}
78 
79 	if (i != tc->size) {
80 		tst_res(TFAIL, "buffer wrong at %i have %02x expected 61",
81 			 i, preadbuf[i]);
82 		return;
83 	}
84 
85 	tst_res(TPASS, "writev() wrote %zi bytes successfully "
86 		 "with content 'a' expectedly ", tc->size);
87 }
88 
setup(void)89 static void setup(void)
90 {
91 	memset(&buf, 0x61, CHUNK);
92 
93 	fd = SAFE_OPEN("file", O_RDWR | O_CREAT, 0644);
94 }
95 
cleanup(void)96 static void cleanup(void)
97 {
98 	if (fd > 0)
99 		SAFE_CLOSE(fd);
100 }
101 
102 static struct tst_test test = {
103 	.tcnt = ARRAY_SIZE(tcases),
104 	.setup = setup,
105 	.cleanup = cleanup,
106 	.test = verify_pwritev,
107 	.needs_tmpdir = 1,
108 };
109