smb_seek.c revision da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* The seek message is sent to set the current file pointer for FID.
* This request should generally only be used by clients wishing to
* find the size of a file, since all read and write requests include
* the read or write file position as part of the SMB. This request
* is inappropriate for large files, as the offsets specified are only
* 32 bits.
*
* The CIFS/1.0 (1996) spec contains the following incomplete statement:
*
* "A seek which results in an Offset which can not be expressed
* in 32 bits returns the least significant."
*
* It would probably be a mistake to make an assumption about what this
* statement means. So, for now, we return an error if the resultant
* file offset is beyond the 32-bit limit.
*/
#include <smbsrv/smb_incl.h>
/*
* smb_com_seek
*
* Client Request Description
* ================================== =================================
* UCHAR WordCount; Count of parameter words = 4
* USHORT Fid; File handle
* USHORT Mode; Seek mode: 0, 1 or 2
* LONG Offset; Relative offset
* USHORT ByteCount; Count of data bytes = 0
*
* The starting point of the seek is set by Mode:
*
* 0 seek from start of file
* 1 seek from current current position
* 2 seek from end of file
*
* The "current position" reflects the offset plus data length specified in
* the previous read, write or seek request, and the pointer set by this
* command will be replaced by the offset specified in the next read, write
* or seek command.
*
* Server Response Description
* ================================== =================================
* UCHAR WordCount; Count of parameter words = 2
* ULONG Offset; Offset from start of file
* USHORT ByteCount; Count of data bytes = 0
*
* The response returns the new file pointer in Offset, which is expressed
* as the offset from the start of the file, and may be beyond the current
* end of file. An attempt to seek before the start of the file sets the
* current file pointer to the start of the file.
*/
int
{
int rc;
/* NOTREACHED */
}
/* NOTREACHED */
}
if (mode == SMB_SEEK_END) {
(void) smb_set_file_size(sr);
}
if (rc == 0) {
return (SDRC_NORMAL_REPLY);
}
/* NOTREACHED */
}
/* NOTREACHED */
}
ASSERT(0);
/* NOTREACHED */
/*
* Although smbsr_raise_error() doesn't return and the compiler is
* told so in smb_kproto.h it still has a problem if it doesn't
* find here a return instruction with a value.
*/
return (0);
}