xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/write/write03.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1*49cdfc7eSAndroid Build Coastguard Worker // SPDX-License-Identifier: GPL-2.0-or-later
2*49cdfc7eSAndroid Build Coastguard Worker /*
3*49cdfc7eSAndroid Build Coastguard Worker  *   Copyright (c) International Business Machines Corp., 2001
4*49cdfc7eSAndroid Build Coastguard Worker  *	07/2001 Ported by John George
5*49cdfc7eSAndroid Build Coastguard Worker  *   Copyright (c) 2017 Fujitsu Ltd.
6*49cdfc7eSAndroid Build Coastguard Worker  *	04/2017 Modified by Jinhui Huang
7*49cdfc7eSAndroid Build Coastguard Worker  */
8*49cdfc7eSAndroid Build Coastguard Worker 
9*49cdfc7eSAndroid Build Coastguard Worker /*
10*49cdfc7eSAndroid Build Coastguard Worker  * DESCRIPTION
11*49cdfc7eSAndroid Build Coastguard Worker  *	Testcase to check that write(2) doesn't corrupt a file when it fails
12*49cdfc7eSAndroid Build Coastguard Worker  *
13*49cdfc7eSAndroid Build Coastguard Worker  * ALGORITHM
14*49cdfc7eSAndroid Build Coastguard Worker  *	Create a file for writing, write 100 bytes to it. Then make write(2)
15*49cdfc7eSAndroid Build Coastguard Worker  *	fail with some erroneous parameter, close the fd. Then reopen the
16*49cdfc7eSAndroid Build Coastguard Worker  *	file in RDONLY mode, and read the contents of the file. Compare the
17*49cdfc7eSAndroid Build Coastguard Worker  *	buffers, to see whether they are same.
18*49cdfc7eSAndroid Build Coastguard Worker  */
19*49cdfc7eSAndroid Build Coastguard Worker 
20*49cdfc7eSAndroid Build Coastguard Worker #include <stdio.h>
21*49cdfc7eSAndroid Build Coastguard Worker #include <errno.h>
22*49cdfc7eSAndroid Build Coastguard Worker #include "tst_test.h"
23*49cdfc7eSAndroid Build Coastguard Worker 
24*49cdfc7eSAndroid Build Coastguard Worker static char *bad_addr;
25*49cdfc7eSAndroid Build Coastguard Worker static char wbuf[BUFSIZ], rbuf[BUFSIZ];
26*49cdfc7eSAndroid Build Coastguard Worker static int fd;
27*49cdfc7eSAndroid Build Coastguard Worker 
verify_write(void)28*49cdfc7eSAndroid Build Coastguard Worker static void verify_write(void)
29*49cdfc7eSAndroid Build Coastguard Worker {
30*49cdfc7eSAndroid Build Coastguard Worker 	fd = SAFE_CREAT("testfile", 0644);
31*49cdfc7eSAndroid Build Coastguard Worker 
32*49cdfc7eSAndroid Build Coastguard Worker 	SAFE_WRITE(SAFE_WRITE_ALL, fd, wbuf, 100);
33*49cdfc7eSAndroid Build Coastguard Worker 
34*49cdfc7eSAndroid Build Coastguard Worker 	if (write(fd, bad_addr, 100) != -1) {
35*49cdfc7eSAndroid Build Coastguard Worker 		tst_res(TFAIL, "write() failed to fail");
36*49cdfc7eSAndroid Build Coastguard Worker 		SAFE_CLOSE(fd);
37*49cdfc7eSAndroid Build Coastguard Worker 		return;
38*49cdfc7eSAndroid Build Coastguard Worker 	}
39*49cdfc7eSAndroid Build Coastguard Worker 
40*49cdfc7eSAndroid Build Coastguard Worker 	SAFE_CLOSE(fd);
41*49cdfc7eSAndroid Build Coastguard Worker 
42*49cdfc7eSAndroid Build Coastguard Worker 	fd = SAFE_OPEN("testfile", O_RDONLY);
43*49cdfc7eSAndroid Build Coastguard Worker 
44*49cdfc7eSAndroid Build Coastguard Worker 	memset(rbuf, 0, BUFSIZ);
45*49cdfc7eSAndroid Build Coastguard Worker 
46*49cdfc7eSAndroid Build Coastguard Worker 	SAFE_READ(0, fd, rbuf, 100);
47*49cdfc7eSAndroid Build Coastguard Worker 
48*49cdfc7eSAndroid Build Coastguard Worker 	if (memcmp(wbuf, rbuf, 100) == 0)
49*49cdfc7eSAndroid Build Coastguard Worker 		tst_res(TPASS, "failure of write() did not corrupt the file");
50*49cdfc7eSAndroid Build Coastguard Worker 	else
51*49cdfc7eSAndroid Build Coastguard Worker 		tst_res(TFAIL, "failure of write() corrupted the file");
52*49cdfc7eSAndroid Build Coastguard Worker 
53*49cdfc7eSAndroid Build Coastguard Worker 	SAFE_CLOSE(fd);
54*49cdfc7eSAndroid Build Coastguard Worker }
55*49cdfc7eSAndroid Build Coastguard Worker 
setup(void)56*49cdfc7eSAndroid Build Coastguard Worker static void setup(void)
57*49cdfc7eSAndroid Build Coastguard Worker {
58*49cdfc7eSAndroid Build Coastguard Worker 	bad_addr = SAFE_MMAP(0, 1, PROT_NONE,
59*49cdfc7eSAndroid Build Coastguard Worker 			MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
60*49cdfc7eSAndroid Build Coastguard Worker 
61*49cdfc7eSAndroid Build Coastguard Worker 	memset(wbuf, '0', 100);
62*49cdfc7eSAndroid Build Coastguard Worker }
63*49cdfc7eSAndroid Build Coastguard Worker 
cleanup(void)64*49cdfc7eSAndroid Build Coastguard Worker static void cleanup(void)
65*49cdfc7eSAndroid Build Coastguard Worker {
66*49cdfc7eSAndroid Build Coastguard Worker 	if (fd > 0)
67*49cdfc7eSAndroid Build Coastguard Worker 		SAFE_CLOSE(fd);
68*49cdfc7eSAndroid Build Coastguard Worker }
69*49cdfc7eSAndroid Build Coastguard Worker 
70*49cdfc7eSAndroid Build Coastguard Worker static struct tst_test test = {
71*49cdfc7eSAndroid Build Coastguard Worker 	.test_all = verify_write,
72*49cdfc7eSAndroid Build Coastguard Worker 	.setup = setup,
73*49cdfc7eSAndroid Build Coastguard Worker 	.cleanup = cleanup,
74*49cdfc7eSAndroid Build Coastguard Worker 	.needs_tmpdir = 1,
75*49cdfc7eSAndroid Build Coastguard Worker };
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