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      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  */
     49 key_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  */
     83 void 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  */
     99 void 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  */
    123 void 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  */
    141 int 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  */
    157 void 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  */
    179 int 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  */
    202 int 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