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  *  FILE        : lftest.c
22  *  DESCRIPTION : The purpose of this test is to verify the file size limitations of a filesystem.
23  *                It writes one buffer at a time and lseeks from the beginning of the file to the
24  *                end of the last write position.  The intent is to test lseek64.
25  *  HISTORY:
26  *           06/19/01  :  Written by Jeff Martin(martinjn@us.ibm.com) to test large files on jfs.
27  *           07/12/01  :  Added timing.
28  *
29  */
30 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <unistd.h>
36 #include <fcntl.h>
37 #include <time.h>
38 
39 /* set write buffer size to whatever floats your boat.  I usually use 1M */
40 #define BSIZE 1048576L
41 char buf[BSIZE];
42 
main(int argc,char * argv[])43 int main(int argc, char *argv[])
44 {
45 	off_t i;
46 	long bufnum;
47 	off_t fd;
48 	time_t time1, time2;
49 	int writecnt = 0, seekcnt = 0, diff;
50 
51 	time1 = time(NULL);
52 
53 	if (argc != 2 || atoi(argv[1]) < 1) {
54 		printf("usage:<# of %ld buffers to write>\n", BSIZE);
55 		exit(3);
56 	}
57 	bufnum = strtol(argv[1], NULL, 0);
58 	printf("Started building a %lu megabyte file @ %s\n", bufnum,
59 	       asctime(localtime(&time1)));
60 
61 	buf[0] = 'A';
62 	for (i = 1; i < BSIZE; i++)
63 		buf[i] = '0';
64 	buf[BSIZE - 1] = 'Z';
65 
66 	if ((fd = creat("large_file", 0755)) == -1)
67 		perror("lftest: ");
68 
69 	for (i = 0; i < bufnum; i++) {
70 		if (write(fd, buf, BSIZE) == -1)
71 			return -1;
72 		else {
73 			printf(".");
74 			writecnt++;
75 			fflush(stdout);
76 		}
77 		fsync(fd);
78 		if (lseek(fd, (i + 1) * BSIZE, 0) == -1)
79 			return -1;
80 		else
81 			seekcnt++;
82 	}
83 	close(fd);
84 	time2 = time(NULL);
85 	printf("\nFinished building a %lu megabyte file @ %s\n", bufnum,
86 	       asctime(localtime(&time2)));
87 	diff = time2 - time1;
88 	printf("Number of Writes: %d\n"
89 	       "Number of Seeks: %d\n"
90 	       "Total time for test to run: %d minute(s) and %d seconds\n",
91 	       writecnt, seekcnt, diff / 60, diff % 60);
92 
93 	return 0;
94 }
95