/*-
 * Copyright (c) 2002 Marcel Moolenaar
 * 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.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
#ifdef __FBSDID
__FBSDID("$FreeBSD: src/sbin/gpt/map.c,v 1.6 2005/08/31 01:47:19 marcel Exp $");
#endif
#ifdef __RCSID
__RCSID("$NetBSD: map.c,v 1.16 2023/12/05 17:23:19 tsutsui Exp $");
#endif

#include <sys/types.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>

#include "map.h"
#include "gpt.h"
#include "gpt_private.h"

static map_t
map_create(off_t start, off_t size, int type)
{
        map_t m;

        m = calloc(1, sizeof(*m));
        if (m == NULL)
                return NULL;
        m->map_start = start;
        m->map_size = size;
        m->map_next = m->map_prev = NULL;
        m->map_type = type;
        m->map_index = 0;
        m->map_data = NULL;
        m->map_alloc = 0;
        return m;
}

static void
map_destroy(map_t m)
{
        if (m == NULL)
                return;
        if (m->map_alloc)
                free(m->map_data);
        free(m);
}

static const char *maptypes[] = {
        "unused",
        "mbr",
        "mbr partition",
        "primary gpt header",
        "secondary gpt header",
        "primary gpt table",
        "secondary gpt table",
        "gpt partition",
        "protective mbr",
};

static const char *
map_type(int t)
{
        if ((size_t)t >= __arraycount(maptypes))
                return "*unknown*";
        return maptypes[t];
}

map_t
map_add(gpt_t gpt, off_t start, off_t size, int type, void *data, int alloc)
{
        map_t m, n, p;

#ifdef DEBUG
        printf("add: %s %#jx %#jx\n", map_type(type), (uintmax_t)start,
            (uintmax_t)size);
        for (n = gpt->mediamap; n; n = n->map_next)
                printf("have: %s %#jx %#jx\n", map_type(n->map_type),
                    (uintmax_t)n->map_start, (uintmax_t)n->map_size);
#endif

        n = gpt->mediamap;
        while (n != NULL && n->map_start + n->map_size <= start)
                n = n->map_next;
        if (n == NULL) {
                if (!(gpt->flags & GPT_QUIET))
                        gpt_warnx(gpt, "Can't find map");
                return NULL;
        }

        if (n->map_start + n->map_size < start + size) {
                if (!(gpt->flags & GPT_QUIET))
                        gpt_warnx(gpt, "map entry doesn't fit media: "
                            "new start + new size < start + size\n"
                            "(%jx + %jx < %jx + %jx)",
                            n->map_start, n->map_size, start, size);
                return NULL;
        }

        if (n->map_start == start && n->map_size == size) {
                if (n->map_type != MAP_TYPE_UNUSED) {
                        if (n->map_type != MAP_TYPE_MBR_PART ||
                            type != MAP_TYPE_GPT_PART) {
                                if (!(gpt->flags & GPT_QUIET))
                                        gpt_warnx(gpt,
                                            "partition(%ju,%ju) mirrored",
                                            (uintmax_t)start, (uintmax_t)size);
                        }
                }
                n->map_type = type;
                n->map_data = data;
                n->map_alloc = alloc;
                return n;
        }

        if (n->map_type != MAP_TYPE_UNUSED) {
                if (n->map_type != MAP_TYPE_MBR_PART ||
                    type != MAP_TYPE_GPT_PART) {
                        gpt_warnx(gpt, "bogus map current=%s new=%s",
                            map_type(n->map_type), map_type(type));
                        return NULL;
                }
                n->map_type = MAP_TYPE_UNUSED;
        }

        m = map_create(start, size, type);
        if (m == NULL)
                goto oomem;

        m->map_data = data;
        m->map_alloc = alloc;

        if (start == n->map_start) {
                m->map_prev = n->map_prev;
                m->map_next = n;
                if (m->map_prev != NULL)
                        m->map_prev->map_next = m;
                else
                        gpt->mediamap = m;
                n->map_prev = m;
                n->map_start += size;
                n->map_size -= size;
        } else if (start + size == n->map_start + n->map_size) {
                p = n;
                m->map_next = p->map_next;
                m->map_prev = p;
                if (m->map_next != NULL)
                        m->map_next->map_prev = m;
                p->map_next = m;
                p->map_size -= size;
        } else {
                p = map_create(n->map_start, start - n->map_start, n->map_type);
                if (p == NULL)
                        goto oomem;
                n->map_start += p->map_size + m->map_size;
                n->map_size -= (p->map_size + m->map_size);
                p->map_prev = n->map_prev;
                m->map_prev = p;
                n->map_prev = m;
                m->map_next = n;
                p->map_next = m;
                if (p->map_prev != NULL)
                        p->map_prev->map_next = p;
                else
                        gpt->mediamap = p;
        }

        return m;
oomem:
        map_destroy(m);
        gpt_warn(gpt, "Can't create map");
        return NULL;
}

map_t
map_alloc(gpt_t gpt, off_t start, off_t size, off_t alignment)
{
        off_t delta;
        map_t m;

        if (alignment > 0) {
                if ((start % alignment) != 0)
                        start = (start + alignment) / alignment * alignment;
                if ((size % alignment) != 0)
                        size = (size + alignment) / alignment * alignment;
        }

        for (m = gpt->mediamap; m != NULL; m = m->map_next) {
                if (m->map_type != MAP_TYPE_UNUSED || m->map_start < 2)
                        continue;
                if (start != 0 && m->map_start > start)
                        return NULL;

                if (start != 0)
                        delta = start - m->map_start;
                else if (alignment > 0 && m->map_start % alignment != 0)
                        delta = (m->map_start + alignment) /
                                alignment * alignment - m->map_start;
                else
                        delta = 0;

                if (size == 0 || m->map_size - delta >= size) {
                        if (m->map_size - delta < alignment)
                                continue;
                        if (size == 0) {
                                if (alignment > 0 &&
                                    (m->map_size - delta) % alignment != 0)
                                        size = (m->map_size - delta) /
                                            alignment * alignment;
                                else
                                        size = m->map_size - delta;
                        }
                        return map_add(gpt, m->map_start + delta, size,
                            MAP_TYPE_GPT_PART, NULL, 0);
                }
        }

        return NULL;
}

off_t
map_resize(gpt_t gpt, map_t m, off_t size, off_t alignment)
{
        map_t n, o;
        off_t alignsize, prevsize;

        n = m->map_next;

        if (size < 0 || alignment < 0) {
                gpt_warnx(gpt, "negative size or alignment");
                return -1;
        }
        /* Size == 0 means to use whole region of the following unused map */
        if (size == 0) { 
                if (n == NULL) {
                        // XXX: we could just turn the map to UNUSED!
                        gpt_warnx(gpt, "Can't delete, next map is not found");
                        return -1;
                }
                if (n->map_type != MAP_TYPE_UNUSED) {
                        gpt_warnx(gpt, "Can't delete, next map is in use");
                        return -1;
                }
                if (alignment == 0) {
                        size = m->map_size + n->map_size;
                        m->map_size = size;
                        m->map_next = n->map_next;
                        if (n->map_next != NULL)
                                n->map_next->map_prev = m;
                        map_destroy(n);
                        return size;
                } else { /* alignment > 0 */
                        prevsize = m->map_size;
                        size = ((m->map_size + n->map_size) / alignment)
                            * alignment;
                        if (size == prevsize) {
                                m->map_size = size;
                                return size;
                        } else if (size < prevsize) {
                                gpt_warnx(gpt, "Can't coalesce %ju <= %ju",
                                    (uintmax_t)prevsize, (uintmax_t)size);
                                return -1;
                        }
                        m->map_size = size;
                        n->map_start += size - prevsize;
                        n->map_size -= size - prevsize;
                        if (n->map_size == 0) {
                                m->map_next = n->map_next;
                                if (n->map_next != NULL)
                                        n->map_next->map_prev = m;
                                map_destroy(n);
                        }
                        return size;
                }
        }
                        
        alignsize = size;
        if (alignment % size != 0)
                alignsize = (size + alignment) / alignment * alignment;

        if (alignsize < m->map_size) {          /* shrinking */
                prevsize = m->map_size;
                m->map_size = alignsize;
                if (n == NULL || n->map_type != MAP_TYPE_UNUSED) {
                        o = map_create(m->map_start + alignsize,
                                  prevsize - alignsize, MAP_TYPE_UNUSED);
                        if (o == NULL) {
                                gpt_warn(gpt, "Can't create map");
                                return -1;
                        }
                        m->map_next = o;
                        o->map_prev = m;
                        o->map_next = n;
                        if (n != NULL)
                                n->map_prev = o;
                        return alignsize;
                } else {
                        n->map_start -= alignsize;
                        n->map_size += alignsize;
                        return alignsize;
                }
        } else if (alignsize > m->map_size) {           /* expanding */
                if (n == NULL) {
                        gpt_warnx(gpt, "Can't expand map, no space after it");
                        return -1;
                }
                if (n->map_type != MAP_TYPE_UNUSED) {
                        gpt_warnx(gpt,
                            "Can't expand map, next map after it in use");
                        return -1;
                }
                if (n->map_size < alignsize - m->map_size) {
                        gpt_warnx(gpt,
                            "Can't expand map, not enough space in the"
                            " next map after it");
                        return -1;
                }
                n->map_size -= alignsize - m->map_size;
                n->map_start += alignsize - m->map_size;
                if (n->map_size == 0) {
                        m->map_next = n->map_next;
                        if (n->map_next != NULL)
                                n->map_next->map_prev = m;
                        map_destroy(n);
                }
                m->map_size = alignsize;
                return alignsize;
        } else                                          /* correct size */
                return alignsize;
}

map_t
map_find(gpt_t gpt, int type)
{
        map_t m;

        m = gpt->mediamap;
        while (m != NULL && m->map_type != type)
                m = m->map_next;
        return m;
}

map_t
map_first(gpt_t gpt)
{
        return gpt->mediamap;
}

map_t
map_last(gpt_t gpt)
{
        map_t m;

        m = gpt->mediamap;
        while (m != NULL && m->map_next != NULL)
                m = m->map_next;
        return m;
}

off_t
map_free(gpt_t gpt, off_t start, off_t size)
{
        map_t m;

        m = gpt->mediamap;

        while (m != NULL && m->map_start + m->map_size <= start)
                m = m->map_next;
        if (m == NULL || m->map_type != MAP_TYPE_UNUSED)
                return 0LL;
        if (size)
                return (m->map_start + m->map_size >= start + size) ? 1 : 0;
        return m->map_size - (start - m->map_start);
}

int
map_init(gpt_t gpt, off_t size)
{
        char buf[32];

        gpt->mediamap = map_create(0LL, size, MAP_TYPE_UNUSED);
        if (gpt->mediamap == NULL) {
                gpt_warn(gpt, "Can't create map");
                return -1;
        }
        gpt->lbawidth = snprintf(buf, sizeof(buf), "%ju", (uintmax_t)size);
        if (gpt->lbawidth < 5)
                gpt->lbawidth = 5;
        return 0;
}