/*      $NetBSD: cd9660_node.c,v 1.38 2017/05/26 14:34:19 riastradh Exp $       */

/*-
 * Copyright (c) 1982, 1986, 1989, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley
 * by Pace Willisson (pace@blitz.com).  The Rock Ridge Extension
 * Support code is derived from software contributed to Berkeley
 * by Atsushi Murai (amurai@spec.co.jp).
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)cd9660_node.c       8.8 (Berkeley) 5/22/95
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cd9660_node.c,v 1.38 2017/05/26 14:34:19 riastradh Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/kernel.h>
#include <sys/pool.h>
#include <sys/stat.h>

#include <fs/cd9660/iso.h>
#include <fs/cd9660/cd9660_extern.h>
#include <fs/cd9660/cd9660_node.h>
#include <fs/cd9660/cd9660_mount.h>
#include <fs/cd9660/iso_rrip.h>

struct pool cd9660_node_pool;

static u_int cd9660_chars2ui(const u_char *, int);

/*
 * Initialize pool for nodes.
 */
void
cd9660_init(void)
{

        malloc_type_attach(M_ISOFSMNT);
        pool_init(&cd9660_node_pool, sizeof(struct iso_node), 0, 0, 0,
            "cd9660nopl", &pool_allocator_nointr, IPL_NONE);
}

/*
 * Reinitialize.
 */

void
cd9660_reinit(void)
{

}

/*
 * Destroy node pool.
 */
void
cd9660_done(void)
{
        pool_destroy(&cd9660_node_pool);
        malloc_type_detach(M_ISOFSMNT);
}

/*
 * Last reference to an inode, write the inode out and if necessary,
 * truncate and deallocate the file.
 */
int
cd9660_inactive(void *v)
{
        struct vop_inactive_v2_args /* {
                struct vnode *a_vp;
                bool *a_recycle;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;
        struct iso_node *ip = VTOI(vp);
        int error = 0;

        /*
         * If we are done with the inode, reclaim it
         * so that it can be reused immediately.
         */
        ip->i_flag = 0;
        *ap->a_recycle = (ip->inode.iso_mode == 0);
        return error;
}

/*
 * Reclaim an inode so that it can be used for other purposes.
 */
int
cd9660_reclaim(void *v)
{
        struct vop_reclaim_v2_args /* {
                struct vnode *a_vp;
                struct lwp *a_l;
        } */ *ap = v;
        struct vnode *vp = ap->a_vp;

        VOP_UNLOCK(vp);

        /*
         * Purge old data structures associated with the inode.
         */
        genfs_node_destroy(vp);
        pool_put(&cd9660_node_pool, vp->v_data);
        vp->v_data = NULL;
        return (0);
}

/*
 * File attributes
 */
void
cd9660_defattr(struct iso_directory_record *isodir, struct iso_node *inop,
        struct buf *bp)
{
        struct buf *bp2 = NULL;
        struct iso_mnt *imp;
        struct iso_extended_attributes *ap = NULL;
        int off;

        if (isonum_711(isodir->flags)&2) {
                inop->inode.iso_mode = S_IFDIR;
                /*
                 * If we return 2, fts() will assume there are no subdirectories
                 * (just links for the path and .), so instead we return 1.
                 */
                inop->inode.iso_links = 1;
        } else {
                inop->inode.iso_mode = S_IFREG;
                inop->inode.iso_links = 1;
        }
        if (!bp
            && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
            && (off = isonum_711(isodir->ext_attr_length))) {
                cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift),
                    NULL, &bp2);
                bp = bp2;
        }
        if (bp) {
                ap = (struct iso_extended_attributes *)bp->b_data;

                if (isonum_711(ap->version) == 1) {
                        if (!(ap->perm[1]&0x10))
                                inop->inode.iso_mode |= S_IRUSR;
                        if (!(ap->perm[1]&0x40))
                                inop->inode.iso_mode |= S_IXUSR;
                        if (!(ap->perm[0]&0x01))
                                inop->inode.iso_mode |= S_IRGRP;
                        if (!(ap->perm[0]&0x04))
                                inop->inode.iso_mode |= S_IXGRP;
                        if (!(ap->perm[0]&0x10))
                                inop->inode.iso_mode |= S_IROTH;
                        if (!(ap->perm[0]&0x40))
                                inop->inode.iso_mode |= S_IXOTH;
                        inop->inode.iso_uid = isonum_723(ap->owner); /* what about 0? */
                        inop->inode.iso_gid = isonum_723(ap->group); /* what about 0? */
                } else
                        ap = NULL;
        }
        if (!ap) {
                inop->inode.iso_mode |=
                    S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
                inop->inode.iso_uid = (uid_t)0;
                inop->inode.iso_gid = (gid_t)0;
        }
        if (bp2)
                brelse(bp2, 0);
}

/*
 * Time stamps
 */
void
cd9660_deftstamp(struct iso_directory_record *isodir, struct iso_node *inop,
        struct buf *bp)
{
        struct buf *bp2 = NULL;
        struct iso_mnt *imp;
        struct iso_extended_attributes *ap = NULL;
        int off;

        if (!bp
            && ((imp = inop->i_mnt)->im_flags & ISOFSMNT_EXTATT)
            && (off = isonum_711(isodir->ext_attr_length))) {
                cd9660_blkatoff(ITOV(inop), (off_t)-(off << imp->im_bshift),
                    NULL, &bp2);
                bp = bp2;
        }
        if (bp) {
                ap = (struct iso_extended_attributes *)bp->b_data;

                if (isonum_711(ap->version) == 1) {
                        if (!cd9660_tstamp_conv17(ap->ftime,&inop->inode.iso_atime))
                                cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_atime);
                        if (!cd9660_tstamp_conv17(ap->ctime,&inop->inode.iso_ctime))
                                inop->inode.iso_ctime = inop->inode.iso_atime;
                        if (!cd9660_tstamp_conv17(ap->mtime,&inop->inode.iso_mtime))
                                inop->inode.iso_mtime = inop->inode.iso_ctime;
                } else
                        ap = NULL;
        }
        if (!ap) {
                cd9660_tstamp_conv7(isodir->date,&inop->inode.iso_ctime);
                inop->inode.iso_atime = inop->inode.iso_ctime;
                inop->inode.iso_mtime = inop->inode.iso_ctime;
        }
        if (bp2)
                brelse(bp2, 0);
}

int
cd9660_tstamp_conv7(const u_char *pi, struct timespec *pu)
{
        int crtime, days;
        int y, m, d, hour, minute, second, tz;

        y = pi[0] + 1900;
        m = pi[1];
        d = pi[2];
        hour = pi[3];
        minute = pi[4];
        second = pi[5];
        tz = pi[6];

        if (y < 1970) {
                pu->tv_sec  = 0;
                pu->tv_nsec = 0;
                return 0;
        } else {
#ifdef  ORIGINAL
                /* computes day number relative to Sept. 19th,1989 */
                /* don't even *THINK* about changing formula. It works! */
                days = 367*(y-1980)-7*(y+(m+9)/12)/4-3*((y+(m-9)/7)/100+1)/4+275*m/9+d-100;
#else
                /*
                 * Changed :-) to make it relative to Jan. 1st, 1970
                 * and to disambiguate negative division
                 */
                days = 367*(y-1960)-7*(y+(m+9)/12)/4-3*((y+(m+9)/12-1)/100+1)/4+275*m/9+d-239;
#endif
                crtime = ((((days * 24) + hour) * 60 + minute) * 60) + second;

                /* timezone offset is unreliable on some disks */
                if (-48 <= tz && tz <= 52)
                        crtime -= tz * 15 * 60;
        }
        pu->tv_sec  = crtime;
        pu->tv_nsec = 0;
        return 1;
}

static u_int
cd9660_chars2ui(const u_char *begin, int len)
{
        u_int rc;

        for (rc = 0; --len >= 0;) {
                rc *= 10;
                rc += *begin++ - '0';
        }
        return rc;
}

int
cd9660_tstamp_conv17(const u_char *pi, struct timespec *pu)
{
        u_char tbuf[7];

        /* year:"0001"-"9999" -> -1900  */
        tbuf[0] = cd9660_chars2ui(pi,4) - 1900;

        /* month: " 1"-"12"      -> 1 - 12 */
        tbuf[1] = cd9660_chars2ui(pi + 4,2);

        /* day:   " 1"-"31"      -> 1 - 31 */
        tbuf[2] = cd9660_chars2ui(pi + 6,2);

        /* hour:  " 0"-"23"      -> 0 - 23 */
        tbuf[3] = cd9660_chars2ui(pi + 8,2);

        /* minute:" 0"-"59"      -> 0 - 59 */
        tbuf[4] = cd9660_chars2ui(pi + 10,2);

        /* second:" 0"-"59"      -> 0 - 59 */
        tbuf[5] = cd9660_chars2ui(pi + 12,2);

        /* difference of GMT */
        tbuf[6] = pi[16];

        return cd9660_tstamp_conv7(tbuf,pu);
}

ino_t
isodirino(struct iso_directory_record *isodir, struct iso_mnt *imp)
{
        ino_t ino;

        /*
         * Note there is an inverse calculation in
         * cd9660_vfsops.c:cd9660_loadvnode():
         *   ip->iso_start = ino >> imp->im_bshift;
         * and also a calculation of the isodir pointer
         * from an inode in cd9660_vnops.c:cd9660_readlink()
         */
        ino = ((ino_t)isonum_733(isodir->extent) +
                isonum_711(isodir->ext_attr_length)) << imp->im_bshift;
        return ino;
}