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/******************************************************************************
*******************************************************************************
**
** Copyright 2001 Sistina Software, Inc.
**
** This is free software released under the GNU General Public License.
** There is no warranty for this software. See the file COPYING for
** details.
**
*******************************************************************************
******************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#define die(fmt, args...) \
{ \
fprintf(stderr, "%s: ", prog_name); \
fprintf(stderr, fmt, ##args); \
exit(EXIT_FAILURE); \
}
#define do_lseek(fd, off) \
{ \
if (lseek((fd), (off), SEEK_SET) != (off)) \
die("bad seek: %s on line %d of file %s\n", \
strerror(errno),__LINE__, __FILE__); \
}
#define do_read(fd, buff, len) \
{ \
if (read((fd), (buff), (len)) != (len)) \
die("bad read: %s on line %d of file %s\n", \
strerror(errno), __LINE__, __FILE__); \
}
#define do_write(fd, buff, len) \
{ \
if (write((fd), (buff), (len)) != (len)) \
die("bad write: %s on line %d of file %s\n", \
strerror(errno), __LINE__, __FILE__); \
}
#define BLOCK_SIZE (512)
char *prog_name;
unsigned int wait;
unsigned int delay = 0;
int main(int argc, char *argv[])
{
int cont = 1;
int optchar;
int fd;
char *filename;
char buf[BLOCK_SIZE];
unsigned long long offset;
unsigned long long num, last_num = 0;
unsigned int id, clients;
unsigned long long skip = 0;
unsigned int iterations = 0;
unsigned int delay = 0;
prog_name = argv[0];
while (cont) {
optchar = getopt(argc, argv, "i:s:");
switch (optchar) {
case 'i':
iterations = atoi(optarg);
break;
case 's':
delay = atoi(optarg);
break;
case 'h':
die("[-i iterations] [-s usleep] filename offset id clients\n");
case EOF:
cont = 0;
break;
}
}
if (argc - optind < 4)
die("[-i iterations] [-s usleep] filename offset id clients\n");
filename = argv[optind];
offset = atoll(argv[optind + 1]);
id = atoi(argv[optind + 2]);
clients = atoi(argv[optind + 3]);
fd = open(filename, O_RDWR | O_CREAT, 0644);
if (fd < 0)
die("can't open file %s: %s\n", argv[1], strerror(errno));
for (;;) {
do_lseek(fd, offset);
do_read(fd, buf, BLOCK_SIZE);
num = atoll(buf);
if (num % clients == id) {
num++;
sprintf(buf, "%llu\n", num);
printf("%llu %llu\n", num, skip);
if (last_num && last_num + clients != num)
die("bad\n");
do_lseek(fd, offset);
do_write(fd, buf, BLOCK_SIZE);
if (iterations && num >= iterations)
break;
last_num = num;
skip = 0;
} else {
skip++;
}
if (delay)
usleep(delay);
}
close(fd);
exit(EXIT_SUCCESS);
}
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