minix/servers/vfs/time.c
2007-08-07 12:52:47 +00:00

73 lines
1.7 KiB
C

/* This file takes care of those system calls that deal with time.
*
* The entry points into this file are
* do_utime: perform the UTIME system call
* do_stime: PM informs FS about STIME system call
*/
#include "fs.h"
#include <minix/callnr.h>
#include <minix/com.h>
#include "file.h"
#include "fproc.h"
#include "param.h"
#include "vnode.h"
#include <minix/vfsif.h>
#include "vmnt.h"
/*===========================================================================*
* do_utime *
*===========================================================================*/
PUBLIC int do_utime()
{
/* Perform the utime(name, timep) system call. */
register int len;
int r;
uid_t uid;
time_t actime, modtime;
struct vnode *vp;
/* Adjust for case of 'timep' being NULL;
* utime_strlen then holds the actual size: strlen(name)+1.
*/
len = m_in.utime_length;
if (len == 0) len = m_in.utime_strlen;
if (fetch_name(m_in.utime_file, len, M1) != OK) return(err_code);
/* Request lookup */
if ((r = lookup_vp(0 /*flags*/, 0 /*!use_realuid*/, &vp)) != OK) return r;
/* Fill in request fields.*/
if (m_in.utime_length == 0) {
actime = modtime = clock_time();
} else {
actime = m_in.utime_actime;
modtime = m_in.utime_modtime;
}
uid= fp->fp_effuid;
r= OK;
if (vp->v_uid != uid && uid != SU_UID) r = EPERM;
if (m_in.utime_length == 0 && r != OK)
{
/* With a null times pointer, updating the times (to the current time)
* is allow if the object is writable.
*/
r = forbidden(vp, W_BIT, 0 /*!use_realuid*/);
}
if (r != OK)
{
put_vnode(vp);
return r;
}
/* Issue request */
r= req_utime(vp->v_fs_e, vp->v_inode_nr, actime, modtime);
put_vnode(vp);
return r;
}