1 /*
2 * Check decoding of preadv2 and pwritev2 syscalls.
3 *
4 * Copyright (c) 2016 Dmitry V. Levin <ldv@strace.io>
5 * Copyright (c) 2016-2021 The strace developers.
6 * All rights reserved.
7 *
8 * SPDX-License-Identifier: GPL-2.0-or-later
9 */
10
11 #include "tests.h"
12 #include "scno.h"
13
14 #include <errno.h>
15 #include <fcntl.h>
16 #include <stdio.h>
17 #include <sys/uio.h>
18 #include <unistd.h>
19
20 static int
21 pr(const int fd, const struct iovec *const vec,
22 const unsigned long vlen, const unsigned long pos)
23 {
24 return syscall(__NR_preadv2, fd, vec, vlen, pos, 0L, 0L);
25 }
26
27 static int
28 pw(const int fd, const struct iovec *const vec,
29 const unsigned long vlen, const unsigned long pos)
30 {
31 return syscall(__NR_pwritev2, fd, vec, vlen, pos, 0L, 0L);
32 }
33
34 static void
35 dumpio(void)
36 {
37 static char tmp[] = "preadv2-pwritev2-tmpfile";
38 if (open(tmp, O_CREAT|O_RDONLY|O_TRUNC, 0600) != 0)
39 perror_msg_and_fail("creat: %s", tmp);
40 if (open(tmp, O_WRONLY) != 1)
41 perror_msg_and_fail("open: %s", tmp);
42 if (unlink(tmp))
43 perror_msg_and_fail("unlink: %s", tmp);
44
45 static const char w0_c[] = "012";
46 const char *w0_d = hexdump_strdup(w0_c);
47 void *w0 = tail_memdup(w0_c, LENGTH_OF(w0_c));
48
49 static const char w1_c[] = "34567";
50 const char *w1_d = hexdump_strdup(w1_c);
51 void *w1 = tail_memdup(w1_c, LENGTH_OF(w1_c));
52
53 static const char w2_c[] = "89abcde";
54 const char *w2_d = hexdump_strdup(w2_c);
55 void *w2 = tail_memdup(w2_c, LENGTH_OF(w2_c));
56
57 long rc;
58
59 static const char r0_c[] = "01234567";
60 const char *r0_d = hexdump_strdup(r0_c);
61 static const char r1_c[] = "89abcde";
62 const char *r1_d = hexdump_strdup(r1_c);
63
64 const struct iovec w_iov_[] = {
65 {
66 .iov_base = w0,
67 .iov_len = LENGTH_OF(w0_c)
68 }, {
69 .iov_base = w1,
70 .iov_len = LENGTH_OF(w1_c)
71 }, {
72 .iov_base = w2,
73 .iov_len = LENGTH_OF(w2_c)
74 }
75 };
76 const struct iovec *w_iov = tail_memdup(w_iov_, sizeof(w_iov_));
77
78 rc = pw(1, w_iov, 0, 0);
79 if (rc)
80 perror_msg_and_fail("pwritev2: expected 0, returned %ld", rc);
81 tprintf("pwritev2(1, [], 0, 0, 0) = 0\n");
82
83 rc = pw(1, w_iov + ARRAY_SIZE(w_iov_) - 1, 2, 0);
84 tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}, ... /* %p */], 2, 0, 0)"
85 " = %ld %s (%m)\n",
86 w2_c, LENGTH_OF(w2_c), w_iov + ARRAY_SIZE(w_iov_),
87 rc, errno2name());
88
89 const unsigned int w_len =
90 LENGTH_OF(w0_c) + LENGTH_OF(w1_c) + LENGTH_OF(w2_c);
91
92 rc = pw(1, w_iov, ARRAY_SIZE(w_iov_), 0);
93 if (rc != (int) w_len)
94 perror_msg_and_fail("pwritev2: expected %u, returned %ld",
95 w_len, rc);
96 close(1);
97 tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}"
98 ", {iov_base=\"%s\", iov_len=%u}"
99 ", {iov_base=\"%s\", iov_len=%u}], %u, 0, 0) = %u\n"
100 " * %u bytes in buffer 0\n"
101 " | 00000 %-49s %-16s |\n"
102 " * %u bytes in buffer 1\n"
103 " | 00000 %-49s %-16s |\n"
104 " * %u bytes in buffer 2\n"
105 " | 00000 %-49s %-16s |\n",
106 w0_c, LENGTH_OF(w0_c), w1_c, LENGTH_OF(w1_c),
107 w2_c, LENGTH_OF(w2_c), (unsigned int) ARRAY_SIZE(w_iov_), w_len,
108 LENGTH_OF(w0_c), w0_d, w0_c,
109 LENGTH_OF(w1_c), w1_d, w1_c, LENGTH_OF(w2_c), w2_d, w2_c);
110
111 const unsigned int r_len = (w_len + 1) / 2;
112 void *r0 = tail_alloc(r_len);
113 const struct iovec r0_iov_[] = {
114 {
115 .iov_base = r0,
116 .iov_len = r_len
117 }
118 };
119 const struct iovec *r_iov = tail_memdup(r0_iov_, sizeof(r0_iov_));
120
121 rc = pr(0, r_iov, ARRAY_SIZE(r0_iov_), 0);
122 if (rc != (int) r_len)
123 perror_msg_and_fail("preadv2: expected %u, returned %ld",
124 r_len, rc);
125 tprintf("preadv2(0, [{iov_base=\"%s\", iov_len=%u}], %u, 0, 0) = %u\n"
126 " * %u bytes in buffer 0\n"
127 " | 00000 %-49s %-16s |\n",
128 r0_c, r_len, (unsigned int) ARRAY_SIZE(r0_iov_),
129 r_len, r_len, r0_d, r0_c);
130
131 void *r1 = tail_alloc(r_len);
132 void *r2 = tail_alloc(w_len);
133 const struct iovec r1_iov_[] = {
134 {
135 .iov_base = r1,
136 .iov_len = r_len
137 },
138 {
139 .iov_base = r2,
140 .iov_len = w_len
141 }
142 };
143 r_iov = tail_memdup(r1_iov_, sizeof(r1_iov_));
144
145 rc = pr(0, r_iov, ARRAY_SIZE(r1_iov_), r_len);
146 if (rc != (int) w_len - (int) r_len)
147 perror_msg_and_fail("preadv2: expected %d, returned %ld",
148 (int) w_len - r_len, rc);
149 tprintf("preadv2(0, [{iov_base=\"%s\", iov_len=%u}"
150 ", {iov_base=\"\", iov_len=%u}], %u, %u, 0) = %u\n"
151 " * %u bytes in buffer 0\n"
152 " | 00000 %-49s %-16s |\n",
153 r1_c, r_len, w_len, (unsigned int) ARRAY_SIZE(r1_iov_),
154 r_len, w_len - r_len,
155 w_len - r_len, r1_d, r1_c);
156 close(0);
157 }
158
159 int
160 main(void)
161 {
162 const kernel_ulong_t vlen = (kernel_ulong_t) 0xfac1fed2dad3bef4ULL;
163 const unsigned long long pos = 0x7ac5fed6dad7bef8;
164 const kernel_ulong_t pos_l = (kernel_ulong_t) pos;
165 long rc;
166 bool skip_dumpio_test = false;
167
168 tprintf("%s", "");
169
170 #if defined __x86_64__ && defined __ILP32__
171 /*
172 * x32 is the only architecture where preadv2 takes 5 arguments,
173 * see preadv64v2 in kernel sources.
174 */
175 rc = syscall(__NR_preadv2, -1, NULL, vlen, pos_l, 1);
176 #else
177 const kernel_ulong_t pos_h =
178 (sizeof(pos_l) == sizeof(pos)) ?
179 (kernel_ulong_t) 0xbadc0deddeadbeefULL :
180 (kernel_ulong_t) (pos >> 32);
181 rc = syscall(__NR_preadv2, -1, NULL, vlen, pos_l, pos_h, 1);
182 #endif
183 if (rc != -1)
184 error_msg_and_fail("preadv2: expected -1, returned %ld", rc);
185 switch (errno) {
186 case ENOSYS:
187 skip_dumpio_test = true;
188 break;
189 case EBADF:
190 break;
191 default:
192 perror_msg_and_fail("preadv2");
193 }
194 tprintf("preadv2(-1, NULL, %lu, %lld, RWF_HIPRI) = %s\n",
195 (unsigned long) vlen, pos, sprintrc(rc));
196
197 #if defined __x86_64__ && defined __ILP32__
198 /*
199 * x32 is the only architecture where pwritev2 takes 5 arguments,
200 * see pwritev64v2 in kernel sources.
201 */
202 rc = syscall(__NR_pwritev2, -1, NULL, vlen, pos_l, 1);
203 #else
204 rc = syscall(__NR_pwritev2, -1, NULL, vlen, pos_l, pos_h, 1);
205 #endif
206 if (rc != -1)
207 error_msg_and_fail("pwritev2: expected -1, returned %ld", rc);
208 switch (errno) {
209 case ENOSYS:
210 skip_dumpio_test = true;
211 break;
212 case EBADF:
213 break;
214 default:
215 perror_msg_and_fail("pwritev2");
216 }
217 tprintf("pwritev2(-1, NULL, %lu, %lld, RWF_HIPRI) = %s\n",
218 (unsigned long) vlen, pos, sprintrc(rc));
219
220 if (!skip_dumpio_test)
221 dumpio();
222
223 tprintf("%s\n", "+++ exited with 0 +++");
224 return 0;
225 }