/*      $NetBSD: loadfile_zboot.c,v 1.1 2009/03/02 09:33:02 nonaka Exp $        */

/*
 * Copyright (c) 2009 NONAKA Kimihiro <nonaka@netbsd.org>
 * 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 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.
 */

#include <sys/types.h>
#include <sys/bootblock.h>

#include "boot.h"
#include "bootinfo.h"
#include "disk.h"
#include "unixdev.h"
#include "pathnames.h"

#include <lib/libsa/loadfile.h>

#include "compat_linux.h"

static int fdloadfile_zboot(int fd, u_long *marks, int flags);
static int zboot_exec(int fd, u_long *marks, int flags);

int
loadfile_zboot(const char *fname, u_long *marks, int flags)
{
        int fd, error;

        /* Open the file. */
        if ((fd = open(fname, 0)) < 0) {
                WARN(("open %s", fname ? fname : "<default>"));
                return -1;
        }

        /* Load it; save the value of errno across the close() call */
        if ((error = fdloadfile_zboot(fd, marks, flags)) != 0) {
                (void)close(fd);
                errno = error;
                return -1;
        }

        return fd;
}

static int
fdloadfile_zboot(int fd, u_long *marks, int flags)
{
        Elf32_Ehdr elf32;
        ssize_t nr;
        int rval;

        /* Read the exec header. */
        if (lseek(fd, 0, SEEK_SET) == (off_t)-1)
                goto err;
        nr = read(fd, &elf32, sizeof(elf32));
        if (nr == -1) {
                WARN(("read header failed"));
                goto err;
        }
        if (nr != sizeof(elf32)) {
                WARN(("read header short"));
                errno = EFTYPE;
                goto err;
        }

        if (memcmp(elf32.e_ident, ELFMAG, SELFMAG) == 0 &&
            elf32.e_ident[EI_CLASS] == ELFCLASS32) {
                rval = zboot_exec(fd, marks, flags);
        } else {
                rval = 1;
                errno = EFTYPE;
        }

        if (rval == 0)
                return 0;
err:
        return errno;
}

static int
zboot_exec(int fd, u_long *marks, int flags)
{
        static char bibuf[BOOTINFO_MAXSIZE];
        char buf[512];
        struct btinfo_common *help;
        char *p;
        int tofd;
        int sz;
        int i;

        /*
         * set bootargs
         */
        p = bibuf;
        memcpy(p, &bootinfo->nentries, sizeof(bootinfo->nentries));
        p += sizeof(bootinfo->nentries);
        for (i = 0; i < bootinfo->nentries; i++) {
                help = (struct btinfo_common *)(bootinfo->entry[i]);
                if ((p - bibuf) + help->len > BOOTINFO_MAXSIZE)
                        break;

                memcpy(p, help, help->len);
                p += help->len;
        }

        tofd = uopen(_PATH_ZBOOT, LINUX_O_WRONLY);
        if (tofd == -1) {
                printf("%s: can't open (errno %d)\n", _PATH_ZBOOT, errno);
                return 1;
        }

        if (uwrite(tofd, bibuf, p - bibuf) != p - bibuf)
                printf("setbootargs: argument write error\n");

        /* Commit boot arguments. */
        uclose(tofd);

        /*
         * load kernel
         */
        tofd = uopen(_PATH_ZBOOT, LINUX_O_WRONLY);
        if (tofd == -1) {
                printf("%s: can't open (errno %d)\n", _PATH_ZBOOT, errno);
                return 1;
        }

        if (lseek(fd, 0, SEEK_SET) != 0) {
                printf("%s: seek error\n", _PATH_ZBOOT);
                goto err;
        }

        while ((sz = read(fd, buf, sizeof(buf))) == sizeof(buf)) {
                if ((sz = uwrite(tofd, buf, sz)) != sizeof(buf)) {
                        printf("%s: write error\n", _PATH_ZBOOT);
                        goto err;
                }
        }

        if (sz < 0) {
                printf("zboot_exec: read error\n");
                goto err;
        }

        if (sz >= 0 && uwrite(tofd, buf, sz) != sz) {
                printf("zboot_exec: write error\n");
                goto err;
        }

        uclose(tofd);
        /*NOTREACHED*/
        return 0;

err:
        uclose(tofd);
        return 1;
}