1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2015 Fujitsu Ltd.
4 * Author: Xiao Yang <yangx.jy@cn.fujitsu.com>
5 */
6 
7 /*
8 * Test Name: preadv01
9 *
10 * Test Description:
11 * Testcase to check the basic functionality of the preadv(2).
12 * Preadv(2) should succeed to read the expected content of data
13 * and after reading the file, the file offset is not changed.
14 */
15 
16 #define _GNU_SOURCE
17 
18 #include <string.h>
19 #include <sys/uio.h>
20 
21 #include "tst_test.h"
22 #include "preadv.h"
23 
24 #define CHUNK           64
25 
26 static int fd;
27 
28 static struct iovec *rd_iovec;
29 
30 static struct tcase {
31 	int count;
32 	off_t offset;
33 	ssize_t size;
34 	char content;
35 } tcases[] = {
36 	{1, 0, CHUNK, 'a'},
37 	{2, 0, CHUNK, 'a'},
38 	{1, CHUNK*3/2, CHUNK/2, 'b'}
39 };
40 
verify_preadv(unsigned int n)41 void verify_preadv(unsigned int n)
42 {
43 	int i;
44 	char *vec;
45 	struct tcase *tc = &tcases[n];
46 
47 	vec = rd_iovec[0].iov_base;
48 	memset(vec, 0x00, CHUNK);
49 
50 	SAFE_LSEEK(fd, 0, SEEK_SET);
51 
52 	TEST(preadv(fd, rd_iovec, tc->count, tc->offset));
53 	if (TST_RET < 0) {
54 		tst_res(TFAIL | TTERRNO, "Preadv(2) failed");
55 		return;
56 	}
57 
58 	if (TST_RET != tc->size) {
59 		tst_res(TFAIL, "Preadv(2) read %li bytes, expected %zi",
60 			 TST_RET, tc->size);
61 		return;
62 	}
63 
64 	for (i = 0; i < tc->size; i++) {
65 		if (vec[i] != tc->content)
66 			break;
67 	}
68 
69 	if (i < tc->size) {
70 		tst_res(TFAIL, "Buffer wrong at %i have %02x expected %02x",
71 			 i, vec[i], tc->content);
72 		return;
73 	}
74 
75 	if (SAFE_LSEEK(fd, 0, SEEK_CUR) != 0) {
76 		tst_res(TFAIL, "Preadv(2) has changed file offset");
77 		return;
78 	}
79 
80 	tst_res(TPASS, "Preadv(2) read %zi bytes successfully "
81 		 "with content '%c' expectedly", tc->size, tc->content);
82 }
83 
setup(void)84 void setup(void)
85 {
86 	char buf[CHUNK];
87 
88 	fd = SAFE_OPEN("file", O_RDWR | O_CREAT, 0644);
89 
90 	memset(buf, 'a', sizeof(buf));
91 	SAFE_WRITE(1, fd, buf, sizeof(buf));
92 
93 	memset(buf, 'b', sizeof(buf));
94 	SAFE_WRITE(1, fd, buf, sizeof(buf));
95 }
96 
cleanup(void)97 void cleanup(void)
98 {
99 	if (fd > 0)
100 		SAFE_CLOSE(fd);
101 }
102 
103 static struct tst_test test = {
104 	.tcnt = ARRAY_SIZE(tcases),
105 	.setup = setup,
106 	.cleanup = cleanup,
107 	.test = verify_preadv,
108 	.min_kver = "2.6.30",
109 	.needs_tmpdir = 1,
110 	.bufs = (struct tst_buffers []) {
111 		{&rd_iovec, .iov_sizes = (int[]){CHUNK, 0, -1}},
112 		{},
113 	}
114 };
115