/*      $OpenBSD: lif.c,v 1.10 2004/11/22 18:41:41 mickey Exp $ */

/*
 * Copyright (c) 1998-2004 Michael Shalayeff
 * All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR OR HIS RELATIVES 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 MIND, 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.
 */

#include <sys/param.h>
#include <sys/disklabel.h>
#include "libsa.h"

extern int debug;

struct file {
        char f_buf[LIF_FILESTART];/* buffer for lif volume header and dir */
        struct lifvol *f_lp;    /* lif volume header pointer */
        struct lifdir *f_ld;    /* lif dir pointer */
        int     f_nfiles;       /* gross number for lif dir entries */

        off_t   f_seek;         /* seek pointer for file read */
        struct lifdir *f_rd;    /* lif dir pointer for readdir */

        int     f_isdir;        /* special hacky flag for '.' dir */
        int     f_count;        /* this file length */
        int     f_off;          /* this file offset */
};

int
lif_open (path, f)
        char *path;
        struct open_file *f;
{
        struct file *fp;
        struct lifdir *dp;
        char *p, *q;
        struct lif_load load;
        size_t buf_size;
        int err, l;

#ifdef LIFDEBUG
        if (debug)
                printf("lif_open(%s, %p)\n", path, f);
#endif

        fp = alloc(sizeof(*fp));
        /* XXX we're assuming here that sizeof(fp->f_buf) >= LIF_FILESTART */
        if ((err = (f->f_dev->dv_strategy)(f->f_devdata, F_READ, 0,
            sizeof(fp->f_buf), &fp->f_buf, &buf_size)) ||
            buf_size != sizeof(fp->f_buf)) {
#ifdef LIFDEBUG
                if (debug)
                        printf("lif_open: unable to read LIF header (%d)\n", err);
#endif
        } else if ((fp->f_lp = (struct lifvol *)fp->f_buf)->vol_id == LIF_VOL_ID) {
                f->f_fsdata = fp;
                fp->f_ld = (struct lifdir *)(fp->f_buf + LIF_DIRSTART);
                fp->f_seek = 0;
                fp->f_rd = fp->f_ld;
                fp->f_nfiles = lifstob(fp->f_lp->vol_dirsize) /
                        sizeof(struct lifdir);

                /* no dirs on the lif */
                for (p = path + (l = strlen(path)); p >= path; p--)
                        if (*p == '/') {
                                p++;
                                break;
                        }
                if (p > path)
                        path = p;
        } else
                err = EINVAL;

        if (!err && *path != '.') {
                fp->f_isdir = 0;
                err = ENOENT;
                for (dp = fp->f_ld; dp < &fp->f_ld[fp->f_nfiles]; dp++) {
#ifdef LIFDEBUG
                        if (debug)
                                printf("lif_open: "
                                       "%s <--> '%c%c%c%c%c%c%c%c%c%c'\n",
                                       path, dp->dir_name[0], dp->dir_name[1],
                                       dp->dir_name[2], dp->dir_name[3],
                                       dp->dir_name[4], dp->dir_name[5],
                                       dp->dir_name[6], dp->dir_name[7],
                                       dp->dir_name[8], dp->dir_name[9]);
#endif
                        for (p = path, q = dp->dir_name;
                             *q && *q != ' '; q++, p++)
                                if (tolower(*q) != tolower(*p))
                                        break;
                        if ((!*q || *q == ' ') && !*p) {
                                err = 0;
                                break;
                        }
                }
                if (!err) {
                        fp->f_off = lifstodb(dp->dir_addr);
                        if (!(err =(f->f_dev->dv_strategy)(f->f_devdata, F_READ,
                              fp->f_off, sizeof(load), &load, &buf_size)) &&
                            buf_size == sizeof(load)) {
                                /* no checksum */
                                fp->f_count = load.count - sizeof(int);
                                fp->f_off = dbtob(fp->f_off) + sizeof(load);
#ifdef LIFDEBUG
                                if (debug)
                                        printf("lif_open: %u @ %u [%x]\n",
                                               fp->f_count, fp->f_off,
                                               load.address);
#endif
                        } else if (!err)
                                err = EIO;
                }
        } else
                fp->f_isdir = 1;

        if (err) {
                free (fp, sizeof(*fp));
                f->f_fsdata = NULL;
        }
#ifdef LIFDEBUG
        if (debug)
                printf("ret(%d)\n", err);
#endif
        return err;
}

int
lif_close(f)
        struct open_file *f;
{
        free (f->f_fsdata, sizeof(struct file));
        f->f_fsdata = NULL;
        return 0;
}

int
lif_read(f, buf, size, resid)
        struct open_file *f;
        void *buf;
        size_t size;
        size_t *resid;
{
        struct file *fp = (struct file *)f->f_fsdata;
        char *p;
        char bbuf[DEV_BSIZE];
        size_t bsize, count = sizeof(bbuf);
        int err = 0;
        int foff;

#ifdef LIFDEBUG
        if (debug)
                printf("lif_read(%p, %p, %u, %p)\n", f, buf, size, resid);
#endif

        for (p = bbuf; size; fp->f_seek += bsize, p += bsize) {
                twiddle();
                foff = fp->f_off + fp->f_seek;
                if (fp->f_seek >= fp->f_count ||
                    (err = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
                     btodb(foff), count, p, &bsize)))
                        break;
                if (p == bbuf) {
                        bsize = sizeof(bbuf) - (foff & (sizeof(bbuf) - 1));
                        bsize = min(bsize, size);
                        bcopy(bbuf + (foff & (sizeof(bbuf) - 1)), buf, bsize);
                        p = buf;
                }
                count = size -= bsize;
        }
        if (resid)
                *resid = size;

        return err;
}

int
lif_write(f, buf, size, resid)
        struct open_file *f;
        void *buf;
        size_t size;
        size_t *resid;
{
        return EOPNOTSUPP;
}

off_t
lif_seek(f, offset, where)
        struct open_file *f;
        off_t offset;
        int where;
{
        struct file *fp = (struct file *)f->f_fsdata;

        switch (where) {
        case SEEK_SET:
                fp->f_seek = offset;
                break;
        case SEEK_CUR:
                fp->f_seek += offset;
                break;
        case SEEK_END:
                fp->f_seek = fp->f_count - offset;
                break;
        default:
                return (-1);
        }
        return (fp->f_seek);
}

int
lif_stat(f, sb)
        struct open_file *f;
        struct stat *sb;
{
        struct file *fp = (struct file *)f->f_fsdata;

        sb->st_mode = 0755 | (fp->f_isdir? S_IFDIR: 0); /* XXX */
        sb->st_uid = 0;
        sb->st_gid = 0;
        sb->st_size = fp->f_count;
        return 0;
}

int
lif_readdir(f, name)
        struct open_file *f;
        char *name;
{
        struct file *fp = (struct file *)f->f_fsdata;
        char *p;

        if (name) {
                while ((fp->f_rd->dir_name[0] == ' ' ||
                        !fp->f_rd->dir_name[0]) &&
                       (fp->f_rd - fp->f_ld) < fp->f_nfiles)
                        fp->f_rd++;
                if ((fp->f_rd - fp->f_ld) >= fp->f_nfiles) {
                        *name = '\0';
                        return -1;
                }
                strncpy(name, fp->f_rd->dir_name, sizeof(fp->f_rd->dir_name));
                if ((p = strchr(name, ' ')))
                        *p = '\0';
                fp->f_rd++;
        } else
                fp->f_rd = fp->f_ld;

        return 0;
}