/* lflseek.c - lflseek */

#include 

/*------------------------------------------------------------------------
 * lflseek  -  Seek to a specified position in a file
 *------------------------------------------------------------------------
 */
devcall lflseek (
          struct dentry *devptr,        /* Entry in device switch table */
          uint32        offset          /* Byte position in the file    */
        )
{
        struct  lflcblk *lfptr;         /* Ptr to open file table entry */

        /* If file is not open, return an error */

        lfptr = &lfltab[devptr->dvminor];
        wait(lfptr->lfmutex);
        if (lfptr->lfstate != LF_USED) {
                signal(lfptr->lfmutex);
                return SYSERR;
        }

        /* Verify offset is within current file size */

        if (offset > lfptr->lfdirptr->ld_size) {
                signal(lfptr->lfmutex);
                return SYSERR;
        }

        /* Record new offset and invalidate byte pointer (i.e., force   */
        /*   the index and data blocks to be replaced if a successive   */
        /*   call is made to read or write)                             */

        lfptr->lfpos = offset;
        lfptr->lfbyte = &lfptr->lfdblock[LF_BLKSIZ];

        signal(lfptr->lfmutex);
        return OK;
}