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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  *	read04.c
     23  *
     24  * DESCRIPTION
     25  *	Testcase to check if read returns the number of bytes read correctly.
     26  *
     27  * ALGORITHM
     28  *	Create a file and write some bytes out to it.
     29  *	Attempt to read more than written.
     30  *	Check the return count, and the read buffer. The read buffer should be
     31  *	same as the write buffer.
     32  *
     33  * USAGE:  <for command-line>
     34  *  read04 [-c n] [-f] [-i n] [-I x] [-P x] [-t]
     35  *     where,  -c n : Run n copies concurrently.
     36  *             -f   : Turn off functionality Testing.
     37  *             -i n : Execute test n times.
     38  *             -I x : Execute test for x seconds.
     39  *             -P x : Pause for x seconds between iterations.
     40  *             -t   : Turn on syscall timing.
     41  *
     42  * HISTORY
     43  *	07/2001 Ported by Wayne Boyer
     44  *
     45  * RESTRICTIONS
     46  *	None
     47  */
     48 #include <sys/types.h>
     49 #include <sys/stat.h>
     50 #include <stdio.h>
     51 #include <fcntl.h>
     52 #include <errno.h>
     53 #include "test.h"
     54 #include "safe_macros.h"
     55 
     56 void cleanup(void);
     57 void setup(void);
     58 
     59 char *TCID = "read04";
     60 int TST_TOTAL = 1;
     61 
     62 #define TST_SIZE	27	/* could also do strlen(palfa) */
     63 char fname[255];
     64 char palfa[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
     65 int fild;
     66 
     67 int main(int ac, char **av)
     68 {
     69 	int lc;
     70 
     71 	int rfild;
     72 	char prbuf[BUFSIZ];
     73 
     74 	/*
     75 	 * parse standard options
     76 	 */
     77 	tst_parse_opts(ac, av, NULL, NULL);
     78 
     79 	setup();		/* global setup for test */
     80 
     81 	for (lc = 0; TEST_LOOPING(lc); lc++) {
     82 
     83 		tst_count = 0;	/* reset tst_count while looping */
     84 
     85 		if ((rfild = open(fname, O_RDONLY)) == -1) {
     86 			tst_brkm(TBROK, cleanup, "can't open for reading");
     87 		}
     88 		TEST(read(rfild, prbuf, BUFSIZ));
     89 
     90 		if (TEST_RETURN == -1) {
     91 			tst_resm(TFAIL, "call failed unexpectedly");
     92 			continue;
     93 		}
     94 
     95 		if (TEST_RETURN != TST_SIZE) {
     96 			tst_resm(TFAIL, "Bad read count - got %ld - "
     97 				 "expected %d", TEST_RETURN, TST_SIZE);
     98 			continue;
     99 		}
    100 		if (memcmp(palfa, prbuf, TST_SIZE) != 0) {
    101 			tst_resm(TFAIL, "read buffer not equal "
    102 				 "to write buffer");
    103 			continue;
    104 		}
    105 		tst_resm(TPASS, "functionality of read() is correct");
    106 
    107 		SAFE_CLOSE(cleanup, rfild);
    108 	}
    109 
    110 	cleanup();
    111 	tst_exit();
    112 }
    113 
    114 /*
    115  * setup() - performs all ONE TIME setup for this test
    116  */
    117 void setup(void)
    118 {
    119 
    120 	tst_sig(NOFORK, DEF_HANDLER, cleanup);
    121 
    122 	umask(0);
    123 
    124 	TEST_PAUSE;
    125 
    126 	tst_tmpdir();
    127 
    128 	sprintf(fname, "tfile_%d", getpid());
    129 
    130 	if ((fild = creat(fname, 0777)) == -1) {
    131 		tst_brkm(TBROK, cleanup, "creat(%s, 0777) Failed, errno = %d"
    132 			 " : %s", fname, errno, strerror(errno));
    133 	}
    134 	if (write(fild, palfa, TST_SIZE) != TST_SIZE) {
    135 		tst_brkm(TBROK, cleanup, "can't write to Xread");
    136 	}
    137 	close(fild);
    138 }
    139 
    140 /*
    141  * cleanup() - performs all ONE TIME cleanup for this test at completion or
    142  *	       premature exit.
    143  */
    144 void cleanup(void)
    145 {
    146 
    147 	unlink(fname);
    148 	tst_rmdir();
    149 
    150 }
    151