1/*
2 *
3 *   Copyright (c) International Business Machines  Corp., 2001
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/*
21 * NAME
22 *	libmsg.c
23 *
24 * DESCRIPTION
25 *	common routines for the IPC system call tests.
26 *
27 *	The library contains the following routines:
28 *
29 *	getipckey()
30 *	rm_queue()
31 *	init_buf()
32 *	rm_sema()
33 *	getuserid()
34 *	rm_shm()
35 */
36
37#define LIBIPC
38#include "ipcmsg.h"
39#include "ipcsem.h"
40
41#include <pwd.h>
42#include <sys/ipc.h>
43#include <sys/shm.h>
44
45/*
46 * getipckey() - generates and returns a message key used by the "get"
47 *		 calls to create an IPC resource.
48 */
49key_t getipckey(void)
50{
51	const char a = 'a';
52	int ascii_a = (int)a;
53	char *curdir = NULL;
54	size_t size = 0;
55	key_t ipc_key;
56	int proj_id;
57	static int count = 0;
58
59	if (NULL == (curdir = getcwd(curdir, size))) {
60		tst_brkm(TBROK, cleanup, "Can't get current directory "
61			 "in getipckey()");
62	}
63
64	/*
65	 * Get a Sys V IPC key
66	 *
67	 * ftok() requires a character as a second argument.  This is
68	 * refered to as a "project identifier" in the man page.
69	 */
70	proj_id = count % 26 + ascii_a;
71	count++;
72
73	if ((ipc_key = ftok(curdir, proj_id)) == -1) {
74		tst_brkm(TBROK, cleanup, "Can't get msgkey from ftok()");
75	}
76
77	return (ipc_key);
78}
79
80/*
81 * rm_queue() - removes a message queue.
82 */
83void rm_queue(int queue_id)
84{
85	if (queue_id == -1) {	/* no queue to remove */
86		return;
87	}
88
89	if (msgctl(queue_id, IPC_RMID, NULL) == -1) {
90		tst_resm(TINFO, "WARNING: message queue deletion failed.");
91		tst_resm(TINFO, "This could lead to IPC resource problems.");
92		tst_resm(TINFO, "id = %d", queue_id);
93	}
94}
95
96/*
97 * init_buf() - initialize the message buffer with some text and a type.
98 */
99void init_buf(MSGBUF * m_buf, int type, int size)
100{
101	int i;
102	int ascii_a = (int)'a';	/* the ascii value for 'a' */
103
104	/* this fills the message with a repeating alphabet string */
105	for (i = 0; i < size; i++) {
106		m_buf->mtext[i] = ascii_a + (i % 26);
107	}
108
109	/* terminate the message */
110	m_buf->mtext[i] = '\0';
111
112	/* if the type isn't valid, set it to 1 */
113	if (type < 1) {
114		m_buf->mtype = 1;
115	} else {
116		m_buf->mtype = type;
117	}
118}
119
120/*
121 * rm_sema() - removes a semaphore.
122 */
123void rm_sema(int sem_id)
124{
125	union semun arr;
126
127	if (sem_id == -1) {	/* no semaphore to remove */
128		return;
129	}
130
131	if (semctl(sem_id, 0, IPC_RMID, arr) == -1) {
132		tst_resm(TINFO, "WARNING: semaphore deletion failed.");
133		tst_resm(TINFO, "This could lead to IPC resource problems.");
134		tst_resm(TINFO, "id = %d", sem_id);
135	}
136}
137
138/*
139 * getuserid() - return the integer value for the "user" id
140 */
141int getuserid(char *user)
142{
143	struct passwd *ent;
144
145	/* get the uid value for the user */
146	if ((ent = getpwnam(user)) == NULL) {
147		tst_brkm(TBROK, cleanup, "Couldn't get password entry for %s",
148			 user);
149	}
150
151	return (ent->pw_uid);
152}
153
154/*
155 * rm_shm() - removes a shared memory segment.
156 */
157void rm_shm(int shm_id)
158{
159	if (shm_id == -1) {	/* no segment to remove */
160		return;
161	}
162
163	/*
164	 * check for # of attaches ?
165	 */
166
167	if (shmctl(shm_id, IPC_RMID, NULL) == -1) {
168		tst_resm(TINFO, "WARNING: shared memory deletion failed.");
169		tst_resm(TINFO, "This could lead to IPC resource problems.");
170		tst_resm(TINFO, "id = %d", shm_id);
171	}
172}
173
174#define BUFSIZE 512
175
176/*
177 * Get the number of message queues already in use
178 */
179int get_used_msgqueues(void)
180{
181	FILE *f;
182	int used_queues;
183	char buff[BUFSIZE];
184
185	f = popen("ipcs -q", "r");
186	if (!f) {
187		tst_brkm(TBROK | TERRNO, NULL, "pipe failed");
188	}
189	/* FIXME: Start at -4 because ipcs prints four lines of header */
190	for (used_queues = -4; fgets(buff, BUFSIZE, f); used_queues++) ;
191	pclose(f);
192	if (used_queues < 0) {
193		tst_brkm(TBROK, NULL, "Could not read output of 'ipcs' to "
194			 "calculate used message queues");
195	}
196	return used_queues;
197}
198
199/*
200 * Get the max number of message queues allowed on system
201 */
202int get_max_msgqueues(void)
203{
204	FILE *f;
205	char buff[BUFSIZE];
206
207	/* Get the max number of message queues allowed on system */
208	f = fopen("/proc/sys/kernel/msgmni", "r");
209	if (!f) {
210		tst_resm(TBROK, "Could not open /proc/sys/kernel/msgmni");
211		return -1;
212	}
213	if (!fgets(buff, BUFSIZE, f)) {
214		fclose(f);
215		tst_resm(TBROK, "Could not read /proc/sys/kernel/msgmni");
216		return -1;
217	}
218	fclose(f);
219	return atoi(buff);
220}
221