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Arquivotheca.AIX-4.1.3/bos/kernel/pfs/xix_ftrunc.c
seta75D d6fe8fe829 Init
2021-10-11 22:19:34 -03:00

109 lines
2.6 KiB
C

static char sccsid[] = "@(#)12 1.26 src/bos/kernel/pfs/xix_ftrunc.c, syspfs, bos411, 9428A410j 7/7/94 16:53:34";
/*
* COMPONENT_NAME: (SYSPFS) Physical File System
*
* FUNCTIONS: jfs_ftrunc
*
* ORIGINS: 27
*
* IBM CONFIDENTIAL -- (IBM Confidential Restricted when
* combined with the aggregated modules for this product)
* SOURCE MATERIALS
* (C) COPYRIGHT International Business Machines Corp. 1988, 1994
* All Rights Reserved
*
* US Government Users Restricted Rights - Use, duplication or
* disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
*/
#include "jfs/jfslock.h"
#include "jfs/inode.h"
#include "sys/user.h"
#include "sys/errno.h"
#include "sys/file.h"
#include "sys/vfs.h"
/*
* NAME: jfs_ftrunc (vp, flags, length, vinfo, crp)
*
* FUNCTION: Truncate a file to the specified size,
* any full blocks released are freed.
*
* PARAMETERS: vp _ is the pointer to the vnode that represents the file
* to be truncated.
* flags - open flags
* length - new length
* vinfo - unused
* crp - credential
*
* RETURN : Zero is returned if itrunc completes sucessfully.
*
*/
jfs_ftrunc (vp, flags, length, vinfo, crp)
struct vnode *vp; /* Vnode for open file */
int flags; /* Open flags */
offset_t length; /* New length */
caddr_t vinfo; /* Gfs specific inofo */
struct ucred *crp; /* pointer to credential structure */
{
int rc = 0;
struct inode *ip;
struct eflock bf;
extern int iwritelockx();
extern int iwriteunlockx();
ip = VTOIP(vp); /* get inode */
IWRITE_LOCK(ip);
if (ENF_LOCK(ip->i_mode))
{ /* enforced lock mode? */
bf.l_type = F_WRLCK; /* Write lock */
bf.l_whence = 0;
bf.l_start = length; /* start of region to lock */
bf.l_len = 0; /* lock to EOF */
bf.l_pid = U.U_procp->p_pid;
bf.l_sysid = 0;
bf.l_vfs = MNT_JFS;
if ( (rc = common_reclock(ITOGP(ip),
ip->i_size,
length,
&bf,
( (flags & (FNDELAY|FNONBLOCK)) ?
INOFLCK : SLPFLCK|INOFLCK ),
0,
0,
iwritelockx,
iwriteunlockx))
|| bf.l_type != F_UNLCK)
{
rc = (rc) ? rc : EAGAIN;
goto out;
}
}
/* if we're truncating to a non-zero length, we need to
* make sure we are bound it to a vm segment
*/
if (length != 0 && ip->i_seg == 0 && (rc = ibindseg(ip)))
goto out;
rc = itrunc(ip, (off_t) length, crp);
switch(rc)
{
case EMFILE:
case EFBIG:
case EINVAL:
case E2BIG:
break;
default:
clearprivbits(ip, crp);
}
out:
IWRITE_UNLOCK(ip);
return rc;
}