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/*
* locktest - test portlib file-locking functions
*
* This program tries to acquire a lock. If the lock is obtained
* successfully, the program sleeps for 10 seconds, then releases
* the lock. To use the program, start one instance, then start
* another before the first releases the lock. The first instance
* should get the lock, the second instance should fail. When the
* first instance exits, start a third instance. The first instance
* should successfully acquire a lock.
*
* Options:
* -s n sleep for n seconds instead of default 10
* -f name create file with given name instead of default "lock.test"
*
* 29 November 1996
* Paul DuBois
* dubois@primate.wisc.edu
* http://www.primate.wisc.edu/people/dubois/
*/
#include <stdio.h>
#include "portlib.h"
#ifndef bufSiz
#define bufSiz 1024
#endif
static char lockFile[bufSiz] = "lock.test";
static int sleepTime = 10;
static char *usage = "Usage: locktest [ -s sleeptime ] [ -f lockfile ]";
int
main (argc, argv)
int argc;
char *argv[];
{
FILE *f;
--argc; /* skip program name */
++argv;
while (argc > 0 && argv[0][0] == '-')
{
if (strcmp (argv[0], "-s") == 0)
{
if (argc < 2)
{
fprintf (stderr, "%s\n", usage);
exit (1);
}
sleepTime = StrToInt (argv[1]);
argc -= 2;
argv += 2;
}
else if (strcmp (argv[0], "-f") == 0)
{
if (argc < 2)
{
fprintf (stderr, "%s\n", usage);
exit (1);
}
(void) strcpy (lockFile, argv[1]);
argc -= 2;
argv += 2;
}
else
{
fprintf (stderr, "unknown option: %s\n", argv[0]);
fprintf (stderr, "%s\n", usage);
exit (1);
}
}
if (argc != 0)
{
fprintf (stderr, "%s\n", usage);
exit (1);
}
printf ("opening \"%s\" file\n", lockFile);
/*
* Create file if it doesn't exist, but if it does exist,
* don't overwrite the contents. We just want to lock it,
* not destroy it.
*/
if ((f = fopen (lockFile, "a+")) == (FILE *) NULL)
{
printf ("could not open \"%s\", exiting\n", lockFile);
exit (1);
}
printf ("trying to acquire lock\n");
if (AcquireLock (f) == 0)
{
printf ("lock not acquired, exiting\n");
(void) fclose (f);
exit (1);
}
printf ("lock acquired successfully\n");
sleep (sleepTime);
printf ("releasing lock\n");
ReleaseLock (f);
(void) fclose (f);
exit (0);
}
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