/*
 * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*      $NetBSD: cd9660_node.c,v 1.13 1994/12/24 15:30:07 cgd 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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       8.5 (Berkeley) 12/5/94



 * HISTORY
 * 22-Jan-98    radar 1669467 - ISO 9660 CD support - jwc
 * 17-Feb-98    radar 1669467 - changed lock protocols to use the lock manager - chw

 */

#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/kernel.h>
#include <sys/malloc.h>
#include <sys/stat.h>
#include <sys/lock.h>
#include <sys/namei.h>

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

/*
 * Structures associated with iso_node caching.
 */
struct iso_node **isohashtbl;
u_long isohash;
#define INOHASH(device, inum)   (((device) + ((inum)>>12)) & isohash)

#ifdef ISODEVMAP
struct iso_node **idvhashtbl;
u_long idvhash;
#define DNOHASH(device, inum)   (((device) + ((inum)>>12)) & idvhash)
#endif

/* defined in bsd/vfs/vfs_subr.c */
extern int prtactive;   /* 1 => print out reclaim of active vnodes */

extern u_char isonullname[];
/*
 * Initialize hash links for inodes and dnodes.
 */
int
cd9660_init(__unused struct vfsconf *cp)
{

        isohashtbl = hashinit(desiredvnodes, M_ISOFSMNT, &isohash);
#ifdef ISODEVMAP
        idvhashtbl = hashinit(desiredvnodes / 8, M_ISOFSMNT, &idvhash);
#endif
    return 0;
}

#ifdef ISODEVMAP
/*
 * Enter a new node into the device hash list
 */
struct iso_dnode *
iso_dmap(dev_t device, ino_t inum, int create)
{
        register struct iso_dnode **dpp, *dp, *dq;

        dpp = &idvhashtbl[DNOHASH(device, inum)];
        for (dp = *dpp;; dp = dp->d_next) {
                if (dp == NULL)
                        return (NULL);
                if (inum == dp->i_number && device == dp->i_dev)
                        return (dp);

        if (!create)
                return (NULL);

        MALLOC(dp, struct iso_dnode *, sizeof(struct iso_dnode), M_CACHE,
               M_WAITOK);
        dp->i_dev = dev;
        dp->i_number = ino;

        if (dq = *dpp)
                dq->d_prev = dp->d_next;
        dp->d_next = dq;
        dp->d_prev = dpp;
        *dpp = dp;

        return (dp);
}

void
iso_dunmap(dev_t device)
{
        struct iso_dnode **dpp, *dp, *dq;
        
        for (dpp = idvhashtbl; dpp <= idvhashtbl + idvhash; dpp++) {
                for (dp = *dpp; dp != NULL; dp = dq)
                        dq = dp->d_next;
                        if (device == dp->i_dev) {
                                if (dq)
                                        dq->d_prev = dp->d_prev;
                                *dp->d_prev = dq;
                                FREE(dp, M_CACHE);
                        }
                }
        }
}
#endif

/*
 * Use the device/inum pair to find the incore inode, and return a pointer
 * to it. If it is in core, but locked, wait for it.
 */
struct vnode *
cd9660_ihashget(dev_t device, ino_t inum, struct proc *p)
{
        register struct iso_node *ip;
        struct vnode *vp;
        uint32_t vid;

retry:
        for (ip = isohashtbl[INOHASH(device, inum)]; ip; ip = ip->i_next) {
                if (inum == ip->i_number && device == ip->i_dev) {
                          
                        if (ISSET(ip->i_flag, ISO_INALLOC)) {
                                /*
                                 * inode is being created... wait for it
                                 * to be ready for consumption
                                 */
                                SET(ip->i_flag, ISO_INWALLOC);
                                tsleep((caddr_t)ip, PINOD, "cd9960_ihashget", 0);
                                goto retry;
                        }
                        vp = ITOV(ip);
                        /*
                         * the vid needs to be grabbed before we drop
                         * lock protecting the hash
                         */
                        vid = vnode_vid(vp);

                        /*
                         * we currently depend on running under the FS funnel
                         * when we do proper locking and advertise ourselves
                         * as thread safe, we'll need a lock to protect the
                         * hash lookup... this is where we would drop it
                         */
                        if (vnode_getwithvid(vp, vid)) {
                                /*
                                 * If vnode is being reclaimed, or has
                                 * already changed identity, no need to wait
                                 */
                                return (NULL);
                        }       
                        return (vp);
                }
        }
        return (NULL);
}

/*
 * Insert the inode into the hash table, and return it locked.
 */
void
cd9660_ihashins(struct iso_node *ip)
{
        struct iso_node **ipp, *iq;

        /* lock the inode, then put it on the appropriate hash list */

        ipp = &isohashtbl[INOHASH(ip->i_dev, ip->i_number)];
        if ((iq = *ipp))
                iq->i_prev = &ip->i_next;
        ip->i_next = iq;
        ip->i_prev = ipp;
        *ipp = ip;
}

/*
 * Remove the inode from the hash table.
 */
void
cd9660_ihashrem(register struct iso_node *ip)
{
        register struct iso_node *iq;

        if ((iq = ip->i_next))
                iq->i_prev = ip->i_prev;
        *ip->i_prev = iq;
#if 1 /* was ifdef DIAGNOSTIC */
        ip->i_next = NULL;
        ip->i_prev = NULL;
#endif
}

/*
 * Last reference to an inode... if we're done with
 * it, go ahead and recycle it for other use
 */
int
cd9660_inactive(struct vnop_inactive_args *ap)
{
        vnode_t vp = ap->a_vp;
        struct iso_node *ip = VTOI(vp);
        
        /*
         * If we are done with the inode, reclaim it
         * so that it can be reused immediately.
         */
        if (ip->inode.iso_mode == 0)
                vnode_recycle(vp);

        return 0;
}

/*
 * Reclaim an inode so that it can be used for other purposes.
 */
int
cd9660_reclaim(struct vnop_reclaim_args *ap)
{
        vnode_t vp = ap->a_vp;
        struct iso_node *ip = VTOI(vp);
        
        vnode_removefsref(vp);
        /*
         * Remove the inode from its hash chain.
         */
        cd9660_ihashrem(ip);

        if (ip->i_devvp) {
                vnode_t devvp = ip->i_devvp;
                ip->i_devvp = NULL;
                vnode_rele(devvp);
        }
        vnode_clearfsnode(vp);

        if (ip->i_namep != isonullname)
                FREE(ip->i_namep, M_TEMP);
        if (ip->i_riff != NULL)
                FREE(ip->i_riff, M_TEMP);
        FREE_ZONE(ip, sizeof(struct iso_node), M_ISOFSNODE);

        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) & directoryBit ) {
                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 *)buf_dataptr(bp);
                
                if (isonum_711(ap->version) == 1) {
                        if (!(ap->perm[0]&0x40))
                                inop->inode.iso_mode |= VEXEC >> 6;
                        if (!(ap->perm[0]&0x10))
                                inop->inode.iso_mode |= VREAD >> 6;
                        if (!(ap->perm[0]&4))
                                inop->inode.iso_mode |= VEXEC >> 3;
                        if (!(ap->perm[0]&1))
                                inop->inode.iso_mode |= VREAD >> 3;
                        if (!(ap->perm[1]&0x40))
                                inop->inode.iso_mode |= VEXEC;
                        if (!(ap->perm[1]&0x10))
                                inop->inode.iso_mode |= VREAD;
                        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 |= VREAD|VWRITE|VEXEC|(VREAD|VEXEC)>>3|(VREAD|VEXEC)>>6;
                inop->inode.iso_uid = ISO_UNKNOWNUID;
                inop->inode.iso_gid = ISO_UNKNOWNGID;
        }
        if (bp2)
                buf_brelse(bp2);
}

/*
 * 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 *)buf_dataptr(bp);
                
                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)
                buf_brelse(bp2);
}

int
cd9660_tstamp_conv7(u_char *pi, struct timespec *pu)
{
        int crtime, days;
        int y, m, d, hour, minute, second, mytz;
        
        y = pi[0] + 1900;
        m = pi[1];
        d = pi[2];
        hour = pi[3];
        minute = pi[4];
        second = pi[5];
        mytz = 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 <= mytz && mytz <= 52)
                        crtime -= mytz * 15 * 60;
        }
        pu->tv_sec  = crtime;
        pu->tv_nsec = 0;
        return 1;
}

static u_int
cd9660_chars2ui(u_char *begin, int len)
{
        u_int rc;
        
        for (rc = 0; --len >= 0;) {
                rc *= 10;
                rc += *begin++ - '0';
        }
        return rc;
}

int
cd9660_tstamp_conv17(u_char *pi, struct timespec *pu)
{
        u_char buf[7];
        
        /* year:"0001"-"9999" -> -1900  */
        buf[0] = cd9660_chars2ui(pi,4) - 1900;
        
        /* month: " 1"-"12"      -> 1 - 12 */
        buf[1] = cd9660_chars2ui(pi + 4,2);
        
        /* day:   " 1"-"31"      -> 1 - 31 */
        buf[2] = cd9660_chars2ui(pi + 6,2);
        
        /* hour:  " 0"-"23"      -> 0 - 23 */
        buf[3] = cd9660_chars2ui(pi + 8,2);
        
        /* minute:" 0"-"59"      -> 0 - 59 */
        buf[4] = cd9660_chars2ui(pi + 10,2);
        
        /* second:" 0"-"59"      -> 0 - 59 */
        buf[5] = cd9660_chars2ui(pi + 12,2);
        
        /* difference of GMT */
        buf[6] = pi[16];
        
        return cd9660_tstamp_conv7(buf,pu);
}

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

        ino = (isonum_733(isodir->extent) + isonum_711(isodir->ext_attr_length))
              << imp->im_bshift;
        return (ino);
}