minix/servers/vfs/time.c
2012-03-25 21:58:14 +02:00

66 lines
1.8 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
*/
#include "fs.h"
#include <minix/callnr.h>
#include <minix/com.h>
#include "file.h"
#include "fproc.h"
#include "path.h"
#include "param.h"
#include "vnode.h"
#include <minix/vfsif.h>
#include "vmnt.h"
/*===========================================================================*
* do_utime *
*===========================================================================*/
int do_utime()
{
/* Perform the utime(name, timep) system call. */
register int len;
int r;
time_t actime, modtime;
struct vnode *vp;
struct vmnt *vmp;
char fullpath[PATH_MAX];
struct lookup resolve;
lookup_init(&resolve, fullpath, PATH_NOFLAGS, &vmp, &vp);
resolve.l_vmnt_lock = VMNT_WRITE;
resolve.l_vnode_lock = VNODE_READ;
/* 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;
/* Temporarily open the file */
if (fetch_name(m_in.utime_file, len, M1, fullpath) != OK) return(err_code);
if ((vp = eat_path(&resolve, fp)) == NULL) return(err_code);
/* Only the owner of a file or the super user can change its name. */
r = OK;
if (vp->v_uid != fp->fp_effuid && fp->fp_effuid != SU_UID) r = EPERM;
if (m_in.utime_length == 0 && r != OK) r = forbidden(fp, vp, W_BIT);
if (read_only(vp) != OK) r = EROFS; /* Not even su can touch if R/O */
if (r == OK) {
/* Issue request */
if(m_in.utime_length == 0) {
actime = modtime = clock_time();
} else {
actime = m_in.utime_actime;
modtime = m_in.utime_modtime;
}
r = req_utime(vp->v_fs_e, vp->v_inode_nr, actime, modtime);
}
unlock_vnode(vp);
unlock_vmnt(vmp);
put_vnode(vp);
return(r);
}