lfibget.c

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/* lfibget.c - lfibget */

#include <xinu.h>

/*------------------------------------------------------------------------
 *  lfibget  -  Get an index block from disk given its number (assumes
 *          mutex is held)
 *------------------------------------------------------------------------
 */
void    lfibget(
      did32     diskdev,    /* Device ID of disk to use */
      ibid32    inum,       /* ID of index block to fetch   */
      struct lfiblk *ibuff      /* Buffer to hold index block   */
    )   
{
    char    *from, *to;     /* Pointers used in copying */
    int32   i;          /* Loop index used during copy  */
    char    dbuff[LF_BLKSIZ];   /* Buffer to hold disk block    */

    /* Read disk block that contains the specified index block */

    read(diskdev, dbuff, ib2sect(inum));

    /* Copy specified index block to caller's ibuff */

    from = dbuff + ib2disp(inum);
    to = (char *)ibuff;
    for (i=0 ; i<sizeof(struct lfiblk) ; i++)
        *to++ = *from++;
    return;
}