Byte range locking

[Srikanta Shivanna]

I observed it while running the following modified torture test:

static BOOL run_locktest7(int dummy)
{
	static struct cli_state cli1;
	const char *fname = "\\lockt7.lck";
	int fnum1;
	BOOL ret;
	char buf[200];
	BOOL correct = True;

	if (!torture_open_connection(&cli1)) {
		return False;
	}

	cli_sockopt(&cli1, sockops);

	printf("starting locktest7\n");

	cli_unlink(&cli1, fname);

	fnum1 = cli_open(&cli1, fname, O_RDWR|O_CREAT|O_EXCL, DENY_NONE);

	memset(buf, 0, sizeof(buf));

	if (cli_write(&cli1, fnum1, 0, buf, 0, sizeof(buf)) != sizeof(buf)) {
		printf("Failed to create file\n");
		correct = False;
		goto fail;
	}

	cli_setpid(&cli1, 1);	
	
	if (!cli_lock(&cli1, fnum1, 130, 4, 0, READ_LOCK))
	{
	    printf("Unable to apply read lock on range 130:4\n");
	    goto fail;	    
	}
	else
	{
	   printf("pid1 successfully read locked range 130:4\n");
	}

      if (cli_read(&cli1, fnum1, buf, 130, 4) != 4)
	{
	    printf("pid1 unable to read the range 130:4\n");
	}
	else
	{
	    printf("pid1 successfully read the range 130:4\n");
	}
	
      if (cli_write(&cli1, fnum1, 0, buf, 130, 4) != 4)
	{
	    printf("pid1 unable to write to the range 130:4\n");
	}
	else
	{
	    printf("pid1 successfully wrote to the range 130:4\n");
	}

	cli_setpid(&cli1, 2);	
	
      if (cli_read(&cli1, fnum1, buf, 130, 4) != 4)
	{
	    printf("pid2 unable to read the range 130:4\n");
	}
	else
	{
	    printf("pid2 successfully read the range 130:4\n");
	}
	
      if (cli_write(&cli1, fnum1, 0, buf, 130, 4) != 4)
	{
	    printf("pid2 unable to write to the range 130:4\n");
	}
	else
	{
	    printf("pid2 successfully wrote to the range 130:4\n");
	}		

	cli_setpid(&cli1, 1);
fail:
	cli_close(&cli1, fnum1);
	cli_unlink(&cli1, fname);
	torture_close_connection(&cli1);

	printf("finished locktest7\n");
	return correct;
}

-----Original Message-----
From: jra at dp.samba.org [mailto:jra at dp.samba.org]
Sent: Thursday, February 20, 2003 8:51 PM
To: Srikanta Shivanna
Cc: samba-technical at lists.samba.org
Subject: Re: Byte range locking


On Thu, Feb 20, 2003 at 07:50:22PM -0800, Srikanta Shivanna wrote:
> I noticed a difference in byte range locking behavior between Samba (2.2.x) and Windows 2000 server, basically on Samba 2.2.x
> with strict locking enabled,  a client process which owns a shared byte range lock can write to the locked region, this is not allowed
> on Windows 2000 server.  Is there a reason for this Samba behavior?  Is it because of default value of some config option?

Can you give me more information on what open modes, access requested
etc. from the client Win32 code please ?

Thanks,

	Jeremy.