1 /*
2 *
3 * Copyright (c) International Business Machines Corp., 2002
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20 /* 12/20/2002 Port to LTP robbiew@us.ibm.com */
21 /* 06/30/2001 Port to Linux nsharoff@us.ibm.com */
22
23 /*
24 * NAME
25 * shmt3
26 *
27 * CALLS
28 * shmctl(2) shmget(2) shmat(2)
29 *
30 * ALGORITHM
31 * Create one shared memory segment and attach it twice to the same process,
32 * at an address that is chosen by the system. After the first attach has
33 * completed, write to it and then do the second attach.
34 * Verify that the doubly attached segment contains the same data.
35 *
36 */
37
38 #include <stdio.h>
39 #include <sys/types.h>
40 #include <sys/ipc.h>
41 #include <sys/shm.h>
42 #include <errno.h>
43
44 /** LTP Port **/
45 #include "test.h"
46
47 char *TCID = "shmt03"; /* Test program identifier. */
48 int TST_TOTAL = 4; /* Total number of test cases. */
49 /**************/
50
51 #define K_1 1024
52 #define SUCCESSFUL 1
53
54 int first_attach, second_attach;
55 static int rm_shm(int);
56
main(void)57 int main(void)
58 {
59 char *cp1, *cp2;
60 int shmid;
61 key_t key;
62
63 key = (key_t) getpid();
64 errno = 0;
65
66 /*------------------------------------------------------------*/
67
68 if ((shmid = shmget(key, 16 * K_1, IPC_CREAT | 0666)) < 0) {
69 perror("shmget");
70 tst_brkm(TFAIL, NULL,
71 "shmget Failed: shmid = %d, errno = %d\n",
72 shmid, errno);
73 }
74
75 tst_resm(TPASS, "shmget");
76
77 /*------------------------------------------------------------*/
78
79 if ((cp1 = shmat(shmid, NULL, 0)) == (char *)-1) {
80 perror("shmat");
81 tst_resm(TFAIL, "shmat Failed: shmid = %d, errno = %d\n",
82 shmid, errno);
83 } else {
84 *cp1 = '1';
85 *(cp1 + 5 * K_1) = '2';
86 first_attach = SUCCESSFUL;
87 }
88
89 tst_resm(TPASS, "1st shmat");
90
91 /*------------------------------------------------------------*/
92
93 if ((cp2 = shmat(shmid, NULL, 0)) == (char *)-1) {
94 perror("shmat");
95 tst_resm(TFAIL, "shmat Failed: shmid = %d, errno = %d\n",
96 shmid, errno);
97 } else {
98 second_attach = SUCCESSFUL;
99 if ((*cp2 != '1' || *(cp2 + 5 * K_1) != '2') &&
100 first_attach == SUCCESSFUL) {
101 tst_resm(TFAIL, "Error: Shared memory contents\n");
102 }
103 }
104
105 tst_resm(TPASS, "2nd shmat");
106
107 /*---------------------------------------------------------------*/
108
109 rm_shm(shmid);
110
111 if (first_attach && second_attach) {
112 if (*cp2 != '1' || *(cp2 + 5 * K_1) != '2' ||
113 *cp1 != '1' || *(cp1 + 5 * K_1) != '2') {
114 tst_resm(TFAIL, "Error: Shared memory contents\n");
115 }
116 }
117
118 tst_resm(TPASS, "Correct shared memory contents");
119 /*-----------------------------------------------------------------*/
120 tst_exit();
121 }
122
rm_shm(int shmid)123 static int rm_shm(int shmid)
124 {
125 if (shmctl(shmid, IPC_RMID, NULL) == -1) {
126 perror("shmctl");
127 tst_brkm(TFAIL,
128 NULL,
129 "shmctl Failed to remove: shmid = %d, errno = %d\n",
130 shmid, errno);
131 }
132 return (0);
133 }
134