[thirdparty/util-linux.git] / libfdisk / src / partition.c

#include "c.h"
#include "strutils.h"

#ifdef HAVE_LIBBLKID
# include <blkid.h>
#endif

#include "fdiskP.h"
#include "strutils.h"

/**
 * SECTION: partition
 * @title: Partition
 * @short_description: generic label independent partition abstraction
 *
 * The fdisk_partition provides label independent abstraction. The partitions
 * are not directly connected with partition table (label) data. Any change to
 * fdisk_partition does not affects in-memory or on-disk label data.
 *
 * The fdisk_partition is possible to use as a template for
 * fdisk_add_partition() or fdisk_set_partition() operations.
 */

static void init_partition(struct fdisk_partition *pa)
{
        FDISK_INIT_UNDEF(pa->size);
        FDISK_INIT_UNDEF(pa->start);
        FDISK_INIT_UNDEF(pa->partno);
        FDISK_INIT_UNDEF(pa->parent_partno);
        FDISK_INIT_UNDEF(pa->boot);

        INIT_LIST_HEAD(&pa->parts);
}

/**
 * fdisk_new_partition:
 *
 * Returns: new instance.
 */
struct fdisk_partition *fdisk_new_partition(void)
{
        struct fdisk_partition *pa = calloc(1, sizeof(*pa));

        pa->refcount = 1;
        init_partition(pa);
        DBG(PART, ul_debugobj(pa, "alloc"));
        return pa;
}

/**
 * fdisk_reset_partition:
 * @pa: partition
 *
 * Resets partition content.
 */
void fdisk_reset_partition(struct fdisk_partition *pa)
{
        int ref;

        if (!pa)
                return;

        DBG(PART, ul_debugobj(pa, "reset"));
        ref = pa->refcount;

        fdisk_unref_parttype(pa->type);
        free(pa->name);
        free(pa->uuid);
        free(pa->attrs);
        free(pa->fstype);
        free(pa->fsuuid);
        free(pa->fslabel);
        free(pa->start_chs);
        free(pa->end_chs);

        memset(pa, 0, sizeof(*pa));
        pa->refcount = ref;

        init_partition(pa);
}

static struct fdisk_partition *__copy_partition(struct fdisk_partition *o)
{
        struct fdisk_partition *n = fdisk_new_partition();
        int rc;

        if (!n)
                return NULL;

        memcpy(n, o, sizeof(*n));

        /* do not copy reference to lists, etc.*/
        n->refcount = 1;
        INIT_LIST_HEAD(&n->parts);

        if (n->type)
                fdisk_ref_parttype(n->type);

        rc = strdup_between_structs(n, o, name);
        if (!rc)
                rc = strdup_between_structs(n, o, uuid);
        if (!rc)
                rc = strdup_between_structs(n, o, attrs);
        if (!rc)
                rc = strdup_between_structs(n, o, fstype);
        if (!rc)
                rc = strdup_between_structs(n, o, fsuuid);
        if (!rc)
                rc = strdup_between_structs(n, o, fslabel);
        if (!rc)
                rc = strdup_between_structs(n, o, start_chs);
        if (!rc)
                rc = strdup_between_structs(n, o, end_chs);

        if (rc) {
                fdisk_unref_partition(n);
                n = NULL;
        }
        return n;
}

/**
 * fdisk_ref_partition:
 * @pa: partition pointer
 *
 * Increments reference counter.
 */
void fdisk_ref_partition(struct fdisk_partition *pa)
{
        if (pa)
                pa->refcount++;
}

/**
 * fdisk_unref_partition:
 * @pa: partition pointer
 *
 * Decrements reference counter, on zero the @pa is automatically
 * deallocated.
 */
void fdisk_unref_partition(struct fdisk_partition *pa)
{
        if (!pa)
                return;

        pa->refcount--;
        if (pa->refcount <= 0) {
                list_del(&pa->parts);
                fdisk_reset_partition(pa);
                DBG(PART, ul_debugobj(pa, "free"));
                free(pa);
        }
}

/**
 * fdisk_partition_set_start:
 * @pa: partition
 * @off: offset in sectors, maximal is UINT64_MAX-1
 *
 * Note that zero is valid offset too. Use fdisk_partition_unset_start() to
 * undefine the offset.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_set_start(struct fdisk_partition *pa, fdisk_sector_t off)
{
        if (!pa)
                return -EINVAL;
        if (FDISK_IS_UNDEF(off))
                return -ERANGE;
        pa->start = off;
        pa->fs_probed = 0;
        return 0;
}

/**
 * fdisk_partition_unset_start:
 * @pa: partition
 *
 * Sets the size as undefined. See fdisk_partition_has_start().
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_unset_start(struct fdisk_partition *pa)
{
        if (!pa)
                return -EINVAL;
        FDISK_INIT_UNDEF(pa->start);
        pa->fs_probed = 0;
        return 0;
}

/**
 * fdisk_partition_get_start:
 * @pa: partition
 *
 * The zero is also valid offset. The function may return random undefined
 * value when start offset is undefined (for example after
 * fdisk_partition_unset_start()). Always use fdisk_partition_has_start() to be
 * sure that you work with valid numbers.
 *
 * Returns: start offset in sectors
 */
fdisk_sector_t fdisk_partition_get_start(struct fdisk_partition *pa)
{
        return pa->start;
}

/**
 * fdisk_partition_has_start:
 * @pa: partition
 *
 * Returns: 1 or 0
 */
int fdisk_partition_has_start(struct fdisk_partition *pa)
{
        return pa && !FDISK_IS_UNDEF(pa->start);
}


/**
 * fdisk_partition_cmp_start:
 * @a: partition
 * @b: partition
 *
 * Compares partitions according to start offset, See fdisk_table_sort_partitions().
 *
 * Return: 0 if the same, <0 if @b greater, >0 if @a greater.
 */
int fdisk_partition_cmp_start(struct fdisk_partition *a,
                              struct fdisk_partition *b)
{
        int no_a = FDISK_IS_UNDEF(a->start),
            no_b = FDISK_IS_UNDEF(b->start);

        if (no_a && no_b)
                return 0;
        if (no_a)
                return -1;
        if (no_b)
                return 1;

        return cmp_numbers(a->start, b->start);
}

/**
 * fdisk_partition_start_follow_default
 * @pa: partition
 * @enable: 0|1
 *
 * When @pa used as a template for fdisk_add_partition() when force label driver
 * to use the first possible space for the new partition.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_start_follow_default(struct fdisk_partition *pa, int enable)
{
        if (!pa)
                return -EINVAL;
        pa->start_follow_default = enable ? 1 : 0;
        return 0;
}

/**
 * fdisk_partition_start_is_default:
 * @pa: partition
 *
 * See fdisk_partition_start_follow_default().
 *
 * Returns: 1 if the partition follows default
 */
int fdisk_partition_start_is_default(struct fdisk_partition *pa)
{
        assert(pa);
        return pa->start_follow_default;
}

/**
 * fdisk_partition_set_size:
 * @pa: partition
 * @sz: size in sectors, maximal is UIN64_MAX-1
 *
 * Note that zero is valid size too. Use fdisk_partition_unset_size() to
 * undefine the size.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_set_size(struct fdisk_partition *pa, fdisk_sector_t sz)
{
        if (!pa)
                return -EINVAL;
        if (FDISK_IS_UNDEF(sz))
                return -ERANGE;
        pa->size = sz;
        pa->fs_probed = 0;
        return 0;
}

/**
 * fdisk_partition_unset_size:
 * @pa: partition
 *
 * Sets the size as undefined. See fdisk_partition_has_size().
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_unset_size(struct fdisk_partition *pa)
{
        if (!pa)
                return -EINVAL;
        FDISK_INIT_UNDEF(pa->size);
        pa->fs_probed = 0;
        return 0;
}

/**
 * fdisk_partition_get_size:
 * @pa: partition
 *
 * The zero is also valid size. The function may return random undefined
 * value when size is undefined (for example after fdisk_partition_unset_size()).
 * Always use fdisk_partition_has_size() to be sure that you work with valid
 * numbers.
 *
 * Returns: size offset in sectors
 */
fdisk_sector_t fdisk_partition_get_size(struct fdisk_partition *pa)
{
        return pa->size;
}

/**
 * fdisk_partition_has_size:
 * @pa: partition
 *
 * Returns: 1 or 0
 */
int fdisk_partition_has_size(struct fdisk_partition *pa)
{
        return pa && !FDISK_IS_UNDEF(pa->size);
}

/**
 * fdisk_partition_size_explicit:
 * @pa: partition
 * @enable: 0|1
 *
 * By default libfdisk aligns the size when add the new partition (by
 * fdisk_add_partition()). If you want to disable this functionality use
 * @enable = 1.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_size_explicit(struct fdisk_partition *pa, int enable)
{
        if (!pa)
                return -EINVAL;
        pa->size_explicit = enable ? 1 : 0;
        return 0;
}

/**
 * fdisk_partition_set_partno:
 * @pa: partition
 * @num: partition number (0 is the first partition, maximal is SIZE_MAX-1)
 *
 * Note that zero is valid partno too. Use fdisk_partition_unset_partno() to
 * undefine the partno.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_set_partno(struct fdisk_partition *pa, size_t num)
{
        if (!pa)
                return -EINVAL;
        if (FDISK_IS_UNDEF(num))
                return -ERANGE;
        pa->partno = num;
        return 0;
}

/**
 * fdisk_partition_unset_partno:
 * @pa: partition
 *
 * Sets the partno as undefined. See fdisk_partition_has_partno().
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_unset_partno(struct fdisk_partition *pa)
{
        if (!pa)
                return -EINVAL;
        FDISK_INIT_UNDEF(pa->partno);
        return 0;
}

/**
 * fdisk_partition_get_partno:
 * @pa: partition
 *
 * The zero is also valid partition number. The function may return random
 * value when partno is undefined (for example after fdisk_partition_unset_partno()).
 * Always use fdisk_partition_has_partno() to be sure that you work with valid
 * numbers.
 *
 * Returns: partition number (0 is the first partition)
 */
size_t fdisk_partition_get_partno(struct fdisk_partition *pa)
{
        return pa->partno;
}

/**
 * fdisk_partition_has_partno:
 * @pa: partition
 *
 * Returns: 1 or 0
 */
int fdisk_partition_has_partno(struct fdisk_partition *pa)
{
        return pa && !FDISK_IS_UNDEF(pa->partno);
}


/**
 * fdisk_partition_cmp_partno:
 * @a: partition
 * @b: partition
 *
 * Compares partitions according to partition number See fdisk_table_sort_partitions().
 *
 * Return: 0 if the same, <0 if @b greater, >0 if @a greater.
 */
int fdisk_partition_cmp_partno(struct fdisk_partition *a,
                               struct fdisk_partition *b)
{
        return a->partno - b->partno;
}

/**
 * fdisk_partition_partno_follow_default
 * @pa: partition
 * @enable: 0|1
 *
 * When @pa used as a template for fdisk_add_partition() when force label driver
 * to add a new partition to the default (next) position.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_partno_follow_default(struct fdisk_partition *pa, int enable)
{
        if (!pa)
                return -EINVAL;
        pa->partno_follow_default = enable ? 1 : 0;
        return 0;
}

/**
 * fdisk_partition_set_type:
 * @pa: partition
 * @type: partition type
 *
 * Sets partition type.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_set_type(struct fdisk_partition *pa,
                             struct fdisk_parttype *type)
{
        if (!pa)
                return -EINVAL;

        fdisk_ref_parttype(type);
        fdisk_unref_parttype(pa->type);
        pa->type = type;

        return 0;
}

/**
 * fdisk_partition_get_type:
 * @pa: partition
 *
 * Returns: pointer to partition type.
 */
struct fdisk_parttype *fdisk_partition_get_type(struct fdisk_partition *pa)
{
        return pa ? pa->type : NULL;
}

int fdisk_partition_set_name(struct fdisk_partition *pa, const char *name)
{
        if (!pa)
                return -EINVAL;
        return strdup_to_struct_member(pa, name, name);
}

const char *fdisk_partition_get_name(struct fdisk_partition *pa)
{
        return pa ? pa->name : NULL;
}

int fdisk_partition_set_uuid(struct fdisk_partition *pa, const char *uuid)
{
        if (!pa)
                return -EINVAL;
        return strdup_to_struct_member(pa, uuid, uuid);
}

/**
 * fdisk_partition_has_end:
 * @pa: partition
 *
 * Returns: 1 if the partition has defined last sector
 */
int fdisk_partition_has_end(struct fdisk_partition *pa)
{
        return pa && !FDISK_IS_UNDEF(pa->start) && !FDISK_IS_UNDEF(pa->size);
}

/**
 * fdisk_partition_get_end:
 * @pa: partition
 *
 * This function may returns absolute non-sense, always check
 * fdisk_partition_has_end().
 *
 * Note that partition end is defined by fdisk_partition_set_start() and
 * fdisk_partition_set_size().
 *
 * Returns: last partition sector LBA.
 */
fdisk_sector_t fdisk_partition_get_end(struct fdisk_partition *pa)
{
        return pa->start + pa->size - (pa->size == 0 ? 0 : 1);
}

/**
 * fdisk_partition_end_follow_default
 * @pa: partition
 * @enable: 0|1
 *
 * When @pa used as a template for fdisk_add_partition() when force label
 * driver to use all the possible space for the new partition.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_partition_end_follow_default(struct fdisk_partition *pa, int enable)
{
        if (!pa)
                return -EINVAL;
        pa->end_follow_default = enable ? 1 : 0;
        return 0;
}

/**
 * fdisk_partition_end_is_default:
 * @pa: partition
 *
 * Returns: 1 if the partition follows default
 */
int fdisk_partition_end_is_default(struct fdisk_partition *pa)
{
        assert(pa);
        return pa->end_follow_default;
}

/**
 * fdisk_partition_get_uuid:
 * @pa: partition
 *
 * Returns: partition UUID as string
 */
const char *fdisk_partition_get_uuid(struct fdisk_partition *pa)
{
        return pa ? pa->uuid : NULL;
}

/**
 * fdisk_partition_get_attrs:
 * @pa: partition
 *
 * Returns: partition attributes in string format
 */
const char *fdisk_partition_get_attrs(struct fdisk_partition *pa)
{
        return pa ? pa->attrs : NULL;
}

/**
 * fdisk_partition_set_attrs:
 * @pa: partition
 * @attrs: attributes
 *
 * Sets @attrs to @pa.
 *
 * Return: 0 on success, <0 on error.
 */
int fdisk_partition_set_attrs(struct fdisk_partition *pa, const char *attrs)
{
        if (!pa)
                return -EINVAL;
        return strdup_to_struct_member(pa, attrs, attrs);
}

/**
 * fdisk_partition_is_nested:
 * @pa: partition
 *
 * Returns: 1 if the partition is nested (e.g. MBR logical partition)
 */
int fdisk_partition_is_nested(struct fdisk_partition *pa)
{
        return pa && !FDISK_IS_UNDEF(pa->parent_partno);
}

/**
 * fdisk_partition_is_container:
 * @pa: partition
 *
 * Returns: 1 if the partition is container (e.g. MBR extended partition)
 */
int fdisk_partition_is_container(struct fdisk_partition *pa)
{
        return pa && pa->container;
}

/**
 * fdisk_partition_get_parent:
 * @pa: partition
 * @parent: parent parno
 *
 * Returns: returns devno of the parent
 */
int fdisk_partition_get_parent(struct fdisk_partition *pa, size_t *parent)
{
        if (pa && parent)
                *parent = pa->parent_partno;
        else
                return -EINVAL;
        return 0;
}

/**
 * fdisk_partition_is_used:
 * @pa: partition
 *
 * Returns: 1 if the partition points to some area
 */
int fdisk_partition_is_used(struct fdisk_partition *pa)
{
        return pa && pa->used;
}

/**
 * fdisk_partition_is_bootable:
 * @pa: partition
 *
 * Returns: 1 if the partition has enabled boot flag
 */
int fdisk_partition_is_bootable(struct fdisk_partition *pa)
{
        return pa && pa->boot == 1;
}

/**
 * fdisk_partition_is_freespace:
 * @pa: partition
 *
 * Returns: 1 if @pa points to freespace
 */
int fdisk_partition_is_freespace(struct fdisk_partition *pa)
{
        return pa && pa->freespace;
}

/**
 * fdisk_partition_is_wholedisk:
 * @pa: partition
 *
 * Returns: 1 if the partition is special whole-disk (e.g. SUN) partition
 */
int fdisk_partition_is_wholedisk(struct fdisk_partition *pa)
{
        return pa && pa->wholedisk;
}

/**
 * fdisk_partition_next_partno:
 * @pa: partition
 * @cxt: context
 * @n: returns partition number
 *
 * If @pa specified and partno-follow-default (see fdisk_partition_partno_follow_default())
 * enabled then returns next expected partno or -ERANGE on error.
 *
 * If @pa is NULL, or @pa does not specify any semantic for the next partno
 * then use Ask API to ask user for the next partno. In this case returns 1 if
 * no free partition available. If fdisk dialogs are disabled then returns -EINVAL.
 *
 * Returns: 0 on success, <0 on error, or 1 for non-free partno by Ask API.
 */
int fdisk_partition_next_partno(
                struct fdisk_partition *pa,
                struct fdisk_context *cxt,
                size_t *n)
{
        if (!cxt || !n)
                return -EINVAL;

        if (pa && pa->partno_follow_default) {
                size_t i;

                DBG(PART, ul_debugobj(pa, "next partno (follow default)"));

                for (i = 0; i < cxt->label->nparts_max; i++) {
                        if (!fdisk_is_partition_used(cxt, i)) {
                                *n = i;
                                return 0;
                        }
                }
                return -ERANGE;

        } else if (pa && fdisk_partition_has_partno(pa)) {

                DBG(PART, ul_debugobj(pa, "next partno (specified=%zu)", pa->partno));

                if (pa->partno >= cxt->label->nparts_max ||
                    fdisk_is_partition_used(cxt, pa->partno))
                        return -ERANGE;
                *n = pa->partno;
                return 0;

        } else if (fdisk_has_dialogs(cxt))
                return fdisk_ask_partnum(cxt, n, 1);

        return -EINVAL;
}

static int probe_partition_content(struct fdisk_context *cxt, struct fdisk_partition *pa)
{
        int rc = 1;     /* nothing */

        DBG(PART, ul_debugobj(pa, "start probe #%zu partition [cxt %p] >>>", pa->partno, cxt));

        /* zeroize the current setting */
        strdup_to_struct_member(pa, fstype, NULL);
        strdup_to_struct_member(pa, fsuuid, NULL);
        strdup_to_struct_member(pa, fslabel, NULL);

        if (!fdisk_partition_has_start(pa) ||
            !fdisk_partition_has_size(pa))
                goto done;

#ifdef HAVE_LIBBLKID
        else {
                uintmax_t start, size;

                blkid_probe pr = blkid_new_probe();
                if (!pr)
                        goto done;

                DBG(PART, ul_debugobj(pa, "blkid prober: %p", pr));

                start = fdisk_partition_get_start(pa) * fdisk_get_sector_size(cxt);
                size = fdisk_partition_get_size(pa) * fdisk_get_sector_size(cxt);

                if (blkid_probe_set_device(pr, cxt->dev_fd, start, size) == 0
                    && blkid_do_fullprobe(pr) == 0) {

                        const char *data;
                        rc = 0;

                        if (!blkid_probe_lookup_value(pr, "TYPE",  &data, NULL))
                                rc = strdup_to_struct_member(pa, fstype, data);

                        if (!rc && !blkid_probe_lookup_value(pr, "LABEL", &data, NULL))
                                rc = strdup_to_struct_member(pa, fslabel, data);

                        if (!rc && !blkid_probe_lookup_value(pr, "UUID",  &data, NULL))
                                rc = strdup_to_struct_member(pa, fsuuid, data);
                }

                blkid_free_probe(pr);
                pa->fs_probed = 1;
        }
#endif /* HAVE_LIBBLKID */

done:
        DBG(PART, ul_debugobj(pa, "<<< end probe #%zu partition[cxt %p, rc=%d]", pa->partno, cxt, rc));
        return rc;
}

/**
 * fdisk_partition_to_string:
 * @pa: partition
 * @cxt: context
 * @id: field (FDISK_FIELD_*)
 * @data: returns string with allocated data
 *
 * Returns info about partition converted to printable string.
 *
 * For example
 * <informalexample>
 *   <programlisting>
 *      struct fdisk_partition *pa;
 *
 *      fdisk_get_partition(cxt, 0, &pa);
 *      fdisk_partition_to_string(pa, FDISK_FIELD_UUID, &data);
 *      printf("first partition uuid: %s\n", data);
 *      free(data);
 *      fdisk_unref_partition(pa);
 *   </programlisting>
 * </informalexample>
 *
 * returns UUID for the first partition.
 *
 * Returns: 0 on success, otherwise, a corresponding error.
 */
int fdisk_partition_to_string(struct fdisk_partition *pa,
                              struct fdisk_context *cxt,
                              int id,
                              char **data)
{
        char *p = NULL;
        int rc = 0;
        uint64_t x;

        if (!pa || !cxt || !data)
                return -EINVAL;

        switch (id) {
        case FDISK_FIELD_DEVICE:
                if (pa->freespace)
                        p = strdup(_("Free space"));
                else if (fdisk_partition_has_partno(pa) && cxt->dev_path) {
                        if (cxt->label->flags & FDISK_LABEL_FL_INCHARS_PARTNO)
                                rc = asprintf(&p, "%c", (int) pa->partno + 'a');
                        else
                                p = fdisk_partname(cxt->dev_path, pa->partno + 1);
                }
                break;
        case FDISK_FIELD_BOOT:
                p = fdisk_partition_is_bootable(pa) ? strdup("*") : NULL;
                break;
        case FDISK_FIELD_START:
                if (fdisk_partition_has_start(pa)) {
                        x = fdisk_cround(cxt, pa->start);
                        rc = pa->start_post ?
                                asprintf(&p, "%"PRIu64"%c", x, pa->start_post) :
                                asprintf(&p, "%"PRIu64, x);
                }
                break;
        case FDISK_FIELD_END:
                if (fdisk_partition_has_end(pa)) {
                        x = fdisk_cround(cxt, fdisk_partition_get_end(pa));
                        rc = pa->end_post ?
                                        asprintf(&p, "%"PRIu64"%c", x, pa->end_post) :
                                        asprintf(&p, "%"PRIu64, x);
                }
                break;
        case FDISK_FIELD_SIZE:
                if (fdisk_partition_has_size(pa)) {
                        uint64_t sz = pa->size * cxt->sector_size;

                        switch (cxt->sizeunit) {
                        case FDISK_SIZEUNIT_BYTES:
                                rc = asprintf(&p, "%"PRIu64"", sz);
                                break;
                        case FDISK_SIZEUNIT_HUMAN:
                                if (fdisk_is_details(cxt))
                                        rc = pa->size_post ?
                                                        asprintf(&p, "%"PRIu64"%c", sz, pa->size_post) :
                                                        asprintf(&p, "%"PRIu64, sz);
                                else {
                                        p = size_to_human_string(SIZE_SUFFIX_1LETTER, sz);
                                        if (!p)
                                                rc = -ENOMEM;
                                }
                                break;
                        }
                }
                break;
        case FDISK_FIELD_CYLINDERS:
        {
                uintmax_t sz = fdisk_partition_has_size(pa) ? pa->size : 0;
                if (sz)
                        /* Why we need to cast that to uintmax_t? */
                        rc = asprintf(&p, "%ju", (uintmax_t)(sz / (cxt->geom.heads * cxt->geom.sectors)) + 1);
                break;
        }
        case FDISK_FIELD_SECTORS:
                rc = asprintf(&p, "%ju",
                        fdisk_partition_has_size(pa) ? (uintmax_t) pa->size : 0);
                break;
        case FDISK_FIELD_BSIZE:
                rc = asprintf(&p, "%"PRIu64, pa->bsize);
                break;
        case FDISK_FIELD_FSIZE:
                rc = asprintf(&p, "%"PRIu64, pa->fsize);
                break;
        case FDISK_FIELD_CPG:
                rc = asprintf(&p, "%"PRIu64, pa->cpg);
                break;
        case FDISK_FIELD_TYPE:
                p = pa->type && pa->type->name ? strdup(_(pa->type->name)) : NULL;
                break;
        case FDISK_FIELD_TYPEID:
                if (pa->type && fdisk_parttype_get_string(pa->type))
                        rc = asprintf(&p, "%s", fdisk_parttype_get_string(pa->type));
                else if (pa->type)
                        rc = asprintf(&p, "%x", fdisk_parttype_get_code(pa->type));
                break;
        case FDISK_FIELD_UUID:
                p = pa->uuid && *pa->uuid? strdup(pa->uuid) : NULL;
                break;
        case FDISK_FIELD_NAME:
                p = pa->name && *pa->name ? strdup(pa->name) : NULL;
                break;
        case FDISK_FIELD_ATTR:
                p = pa->attrs && *pa->attrs ? strdup(pa->attrs) : NULL;
                break;
        case FDISK_FIELD_SADDR:
                p = pa->start_chs && *pa->start_chs ? strdup(pa->start_chs) : NULL;
                break;
        case FDISK_FIELD_EADDR:
                p = pa->end_chs && *pa->end_chs? strdup(pa->end_chs) : NULL;
                break;
        case FDISK_FIELD_FSUUID:
                if (pa->fs_probed || probe_partition_content(cxt, pa) == 0)
                        p = pa->fsuuid && *pa->fsuuid ? strdup(pa->fsuuid) : NULL;
                break;
        case FDISK_FIELD_FSLABEL:
                if (pa->fs_probed || probe_partition_content(cxt, pa) == 0)
                        p = pa->fslabel && *pa->fslabel ? strdup(pa->fslabel) : NULL;
                break;
        case FDISK_FIELD_FSTYPE:
                if (pa->fs_probed || probe_partition_content(cxt, pa) == 0)
                        p = pa->fstype && *pa->fstype ? strdup(pa->fstype) : NULL;
                break;
        default:
                return -EINVAL;
        }

        if (rc < 0) {
                rc = -ENOMEM;
                free(p);
                p = NULL;

        } else if (rc > 0)
                rc = 0;

        *data = p;

        return rc;
}


/**
 * fdisk_get_partition:
 * @cxt: context
 * @partno: partition number (0 is the first partition)
 * @pa: returns data about partition
 *
 * Reads disklabel and fills in @pa with data about partition @n.
 *
 * Note that partno may address unused partition and then this function does
 * not fill anything to @pa.  See fdisk_is_partition_used(). If @pa points to
 * NULL then the function allocates a newly allocated fdisk_partition struct,
 * use fdisk_unref_partition() to deallocate.
 *
 * Returns: 0 on success, otherwise, a corresponding error.
 */
int fdisk_get_partition(struct fdisk_context *cxt, size_t partno,
                        struct fdisk_partition **pa)
{
        int rc;
        struct fdisk_partition *np = NULL;

        if (!cxt || !cxt->label || !pa)
                return -EINVAL;
        if (!cxt->label->op->get_part)
                return -ENOSYS;
        if (!fdisk_is_partition_used(cxt, partno))
                return -EINVAL;

        if (!*pa) {
                np = *pa = fdisk_new_partition();
                if (!*pa)
                        return -ENOMEM;
        } else
                fdisk_reset_partition(*pa);

        (*pa)->partno = partno;
        rc = cxt->label->op->get_part(cxt, partno, *pa);

        if (rc) {
                if (np) {
                        fdisk_unref_partition(np);
                        *pa = NULL;
                } else
                        fdisk_reset_partition(*pa);
        } else
                (*pa)->size_explicit = 1;
        return rc;
}

static struct fdisk_partition *resize_get_by_offset(
                        struct fdisk_table *tb,
                        struct fdisk_partition *cur,
                        fdisk_sector_t off)
{
        struct fdisk_partition *pa = NULL;
        struct fdisk_iter itr;

        fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);

        while (fdisk_table_next_partition(tb, &itr, &pa) == 0) {
                if (!fdisk_partition_has_start(pa) || !fdisk_partition_has_size(pa))
                        continue;
                if (fdisk_partition_is_nested(cur) &&
                    pa->parent_partno != cur->parent_partno)
                        continue;
                if (off >= pa->start && off < pa->start + pa->size)
                        return pa;
        }

        return NULL;
}

/*
 * Verify that area addressed by @start is freespace or the @cur[rent]
 * partition and continue to the next table entries until it's freespace, and
 * counts size of all this space.
 *
 * This is core of the partition start offset move operation. We can move the
 * start within the current partition of to the another free space. It's
 * forbidden to move start of the partition to another already defined
 * partition.
 */
static int resize_get_last_possible(
                        struct fdisk_table *tb,
                        struct fdisk_partition *cur,
                        fdisk_sector_t start,
                        fdisk_sector_t *maxsz)
{
        struct fdisk_partition *pa = NULL, *last = NULL;
        struct fdisk_iter itr;

        fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);

        *maxsz = 0;
        DBG(TAB, ul_debugobj(tb, "checking last possible for start=%ju", (uintmax_t) start));


        while (fdisk_table_next_partition(tb, &itr, &pa) == 0) {

                DBG(TAB, ul_debugobj(tb, " checking entry %p [partno=%zu start=%ju, end=%ju, size=%ju%s%s%s]",
                        pa,
                        fdisk_partition_get_partno(pa),
                        (uintmax_t) fdisk_partition_get_start(pa),
                        (uintmax_t) fdisk_partition_get_end(pa),
                        (uintmax_t) fdisk_partition_get_size(pa),
                        fdisk_partition_is_freespace(pa) ? " freespace" : "",
                        fdisk_partition_is_nested(pa)    ? " nested"    : "",
                        fdisk_partition_is_container(pa) ? " container" : ""));

                if (!fdisk_partition_has_start(pa) ||
                    !fdisk_partition_has_size(pa) ||
                    (fdisk_partition_is_container(pa) && pa != cur)) {
                        DBG(TAB, ul_debugobj(tb, "  ignored (no start/size or container)"));
                        continue;
                }

                if (fdisk_partition_is_nested(pa)
                    && fdisk_partition_is_container(cur)
                    && pa->parent_partno == cur->partno) {
                        DBG(TAB, ul_debugobj(tb, "  ignore (nested child of the current partition)"));
                        continue;
                }

                /* The current is nested, free space has to be nested within the same parent */
                if (fdisk_partition_is_nested(cur)
                    && pa->parent_partno != cur->parent_partno) {
                        DBG(TAB, ul_debugobj(tb, "  ignore (nested required)"));
                        continue;
                }

                if (!last) {
                        if (start >= pa->start &&  start < pa->start + pa->size) {
                                if (fdisk_partition_is_freespace(pa) || pa == cur) {
                                        DBG(TAB, ul_debugobj(tb, "  accepted as last"));
                                        last = pa;
                                } else {
                                        DBG(TAB, ul_debugobj(tb, "  failed to set last"));
                                        break;
                                }


                                *maxsz = pa->size - (start - pa->start);
                                DBG(TAB, ul_debugobj(tb, "  new max=%ju", (uintmax_t) *maxsz));
                        }
                } else if (!fdisk_partition_is_freespace(pa) && pa != cur) {
                        DBG(TAB, ul_debugobj(tb, "  no free space behind current"));
                        break;
                } else {
                        last = pa;
                        *maxsz = pa->size - (start - pa->start);
                        DBG(TAB, ul_debugobj(tb, "  new max=%ju (last updated)", (uintmax_t) *maxsz));
                }
        }

        if (last)
                DBG(PART, ul_debugobj(cur, "resize: max size=%ju", (uintmax_t) *maxsz));
        else
                DBG(PART, ul_debugobj(cur, "resize: nothing usable after %ju", (uintmax_t) start));

        return last ? 0 : -1;
}

/*
 * Uses template @tpl to recount start and size change of the partition @res. The
 * @tpl->size and @tpl->start are interpreted as relative to the current setting.
 */
static int recount_resize(
                        struct fdisk_context *cxt, size_t partno,
                        struct fdisk_partition *res, struct fdisk_partition *tpl)
{
        fdisk_sector_t start, size, xsize;
        struct fdisk_partition *cur = NULL;
        struct fdisk_table *tb = NULL;
        int rc;

        DBG(PART, ul_debugobj(tpl, ">>> resize requested"));

        FDISK_INIT_UNDEF(start);
        FDISK_INIT_UNDEF(size);

        rc = fdisk_get_partitions(cxt, &tb);
        if (!rc) {
                /* For resize we do not follow grain to detect free-space, but
                 * we allow to resize with very small granulation. */
                unsigned long org = cxt->grain;

                cxt->grain = cxt->sector_size;
                rc = fdisk_get_freespaces(cxt, &tb);
                cxt->grain = org;
        }
        if (rc) {
                fdisk_unref_table(tb);
                return rc;
        }

        fdisk_table_sort_partitions(tb, fdisk_partition_cmp_start);

        DBG(PART, ul_debugobj(tpl, "resize partition partno=%zu in table:", partno));
        ON_DBG(PART, fdisk_debug_print_table(tb));

        cur = fdisk_table_get_partition_by_partno(tb, partno);
        if (!cur) {
                fdisk_unref_table(tb);
                return -EINVAL;
        }

        /* 1a) set new start - change relative to the current on-disk setting */
        if (tpl->movestart && fdisk_partition_has_start(tpl)) {
                start = fdisk_partition_get_start(cur);
                if (tpl->movestart == FDISK_MOVE_DOWN) {
                        if (fdisk_partition_get_start(tpl) > start)
                                goto erange;
                        start -= fdisk_partition_get_start(tpl);
                } else
                        start += fdisk_partition_get_start(tpl);

                DBG(PART, ul_debugobj(tpl, "resize: moving start %s relative, new start: %ju",
                                tpl->movestart == FDISK_MOVE_DOWN  ? "DOWN" : "UP", (uintmax_t)start));

        /* 1b) set new start - absolute number */
        } else if (fdisk_partition_has_start(tpl)) {
                start = fdisk_partition_get_start(tpl);
                DBG(PART, ul_debugobj(tpl, "resize: moving start to absolute offset: %ju",
                                      (uintmax_t)start));
        }

        /* 2) verify that start is within the current partition or any freespace area */
        if (!FDISK_IS_UNDEF(start)) {
                struct fdisk_partition *area = resize_get_by_offset(tb, cur, start);

                if (area == cur)
                        DBG(PART, ul_debugobj(tpl, "resize: start points to the current partition"));
                else if (area && fdisk_partition_is_freespace(area))
                        DBG(PART, ul_debugobj(tpl, "resize: start points to freespace"));
                else if (!area && start >= cxt->first_lba && start < cxt->first_lba + (cxt->grain / cxt->sector_size))
                        DBG(PART, ul_debugobj(tpl, "resize: start points before first partition"));
                else {
                        DBG(PART, ul_debugobj(tpl, "resize: start verification failed"));
                        goto erange;
                }
        } else {
                /* no change, start points to the current partition */
                DBG(PART, ul_debugobj(tpl, "resize: start unchanged"));
                start = fdisk_partition_get_start(cur);
        }

        /* 3a) set new size -- reduce */
        if (tpl->resize == FDISK_RESIZE_REDUCE && fdisk_partition_has_size(tpl)) {
                DBG(PART, ul_debugobj(tpl, "resize: reduce"));
                size = fdisk_partition_get_size(cur);
                if (fdisk_partition_get_size(tpl) > size)
                        goto erange;
                size -= fdisk_partition_get_size(tpl);

        /* 3b) set new size -- enlarge */
        } else if (tpl->resize == FDISK_RESIZE_ENLARGE && fdisk_partition_has_size(tpl)) {
                DBG(PART, ul_debugobj(tpl, "resize: enlarge"));
                size = fdisk_partition_get_size(cur);
                size += fdisk_partition_get_size(tpl);

        /* 3c) set new size -- no size specified, enlarge to all freespace */
        } else if (tpl->resize == FDISK_RESIZE_ENLARGE) {
                DBG(PART, ul_debugobj(tpl, "resize: enlarge to all possible"));
                if (resize_get_last_possible(tb, cur, start, &size))
                        goto erange;

        /* 3d) set new size -- absolute number */
        } else if (fdisk_partition_has_size(tpl)) {
                DBG(PART, ul_debugobj(tpl, "resize: new absolute size"));
                size = fdisk_partition_get_size(tpl);
        }

        /* 4) verify that size is within the current partition or next free space */
        xsize = !FDISK_IS_UNDEF(size) ? size : fdisk_partition_get_size(cur);

        if (fdisk_partition_has_size(cur)) {
                fdisk_sector_t maxsz;

                if (resize_get_last_possible(tb, cur, start, &maxsz))
                        goto erange;
                DBG(PART, ul_debugobj(tpl, "resize: size=%ju, max=%ju",
                                        (uintmax_t) xsize, (uintmax_t) maxsz));
                if (xsize > maxsz)
                        goto erange;
        }

        if (FDISK_IS_UNDEF(size)) {
                DBG(PART, ul_debugobj(tpl, "resize: size unchanged (undefined)"));
        }


        DBG(PART, ul_debugobj(tpl, "<<< resize: SUCCESS: start %ju->%ju; size %ju->%ju",
                        (uintmax_t) fdisk_partition_get_start(cur), (uintmax_t) start,
                        (uintmax_t) fdisk_partition_get_size(cur), (uintmax_t) size));
        res->start = start;
        res->size = size;
        fdisk_unref_table(tb);
        return 0;
erange:
        DBG(PART, ul_debugobj(tpl, "<<< resize: FAILED"));
        fdisk_warnx(cxt, _("Failed to resize partition #%zu."), partno + 1);
        fdisk_unref_table(tb);
        return -ERANGE;

}

/**
 * fdisk_set_partition:
 * @cxt: context
 * @partno: partition number (0 is the first partition)
 * @pa: new partition setting
 *
 * Modifies disklabel according to setting with in @pa.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_set_partition(struct fdisk_context *cxt, size_t partno,
                        struct fdisk_partition *pa)
{
        struct fdisk_partition *xpa = pa, *tmp = NULL;
        int rc, wipe = 0;

        if (!cxt || !cxt->label || !pa)
                return -EINVAL;
        if (!cxt->label->op->set_part)
                return -ENOSYS;

        pa->fs_probed = 0;

        if (!fdisk_is_partition_used(cxt, partno)) {
                pa->partno = partno;
                return fdisk_add_partition(cxt, pa, NULL);
        }

        if (pa->resize || fdisk_partition_has_start(pa) || fdisk_partition_has_size(pa)) {
                xpa = __copy_partition(pa);
                if (!xpa) {
                        rc = -ENOMEM;
                        goto done;
                }
                xpa->movestart = 0;
                xpa->resize = 0;
                FDISK_INIT_UNDEF(xpa->size);
                FDISK_INIT_UNDEF(xpa->start);

                rc = recount_resize(cxt, partno, xpa, pa);
                if (rc)
                        goto done;
        }

        DBG(CXT, ul_debugobj(cxt, "setting partition %zu %p (start=%ju, end=%ju, size=%ju)",
                    partno, xpa,
                    (uintmax_t) fdisk_partition_get_start(xpa),
                    (uintmax_t) fdisk_partition_get_end(xpa),
                    (uintmax_t) fdisk_partition_get_size(xpa)));

        /* disable wipe for old offset/size setting */
        if (fdisk_get_partition(cxt, partno, &tmp) == 0 && tmp) {
                wipe = fdisk_set_wipe_area(cxt, fdisk_partition_get_start(tmp),
                                                fdisk_partition_get_size(tmp), FALSE);
                fdisk_unref_partition(tmp);
        }

        /* call label driver */
        rc = cxt->label->op->set_part(cxt, partno, xpa);

        /* enable wipe for new offset/size */
        if (!rc && wipe)
                fdisk_wipe_partition(cxt, partno, TRUE);
done:
        DBG(CXT, ul_debugobj(cxt, "set_partition() rc=%d", rc));
        if (xpa != pa)
                fdisk_unref_partition(xpa);
        return rc;
}

/**
 * fdisk_wipe_partition:
 * @cxt: fdisk context
 * @partno: partition number
 * @enable: 0 or 1
 *
 * Enable/disable filesystems/RAIDs wiping in area defined by partition start and size.
 *
 * Returns: <0 in case of error, 0 on success
 * Since: 2.29
 */
int fdisk_wipe_partition(struct fdisk_context *cxt, size_t partno, int enable)
{
        struct fdisk_partition *pa = NULL;
        int rc;

        rc = fdisk_get_partition(cxt, partno, &pa);
        if (rc)
                return rc;

        rc = fdisk_set_wipe_area(cxt, fdisk_partition_get_start(pa),
                                      fdisk_partition_get_size(pa), enable);
        fdisk_unref_partition(pa);
        return rc < 0 ? rc : 0;
}

/**
 * fdisk_partition_has_wipe:
 * @cxt: fdisk context
 * @pa: partition
 *
 * Since: 2.30
 *
 * Returns: 1 if the area specified by @pa will be wiped by write command, or 0.
 */
int fdisk_partition_has_wipe(struct fdisk_context *cxt, struct fdisk_partition *pa)
{
        return fdisk_has_wipe_area(cxt, fdisk_partition_get_start(pa),
                                        fdisk_partition_get_size(pa));
}


/**
 * fdisk_add_partition:
 * @cxt: fdisk context
 * @pa: template for the partition (or NULL)
 * @partno: NULL or returns new partition number
 *
 * If @pa is not specified or any @pa item is missing the libfdisk will ask by
 * fdisk_ask_ API.
 *
 * The @pa template is is important for non-interactive partitioning,
 * especially for MBR where is necessary to differentiate between
 * primary/logical; this is done by start offset or/and partno.
 * The rules for MBR:
 *
 *   A) template specifies start within extended partition: add logical
 *   B) template specifies start out of extended partition: add primary
 *   C) template specifies start (or default), partno < 4: add primary
 *   D) template specifies default start, partno >= 4: add logical
 *
 * otherwise MBR driver uses Ask-API to get missing information.
 *
 * Adds a new partition to disklabel.
 *
 * Returns: 0 on success, <0 on error.
 */
int fdisk_add_partition(struct fdisk_context *cxt,
                        struct fdisk_partition *pa,
                        size_t *partno)
{
        int rc;

        if (!cxt || !cxt->label)
                return -EINVAL;
        if (!cxt->label->op->add_part)
                return -ENOSYS;
        if (fdisk_missing_geometry(cxt))
                return -EINVAL;

        if (pa) {
                pa->fs_probed = 0;
                DBG(CXT, ul_debugobj(cxt, "adding new partition %p", pa));
                if (fdisk_partition_has_start(pa))
                        DBG(CXT, ul_debugobj(cxt, "     start: %ju", (uintmax_t) fdisk_partition_get_start(pa)));
                if (fdisk_partition_has_end(pa))
                        DBG(CXT, ul_debugobj(cxt, "       end: %ju", (uintmax_t) fdisk_partition_get_end(pa)));
                if (fdisk_partition_has_size(pa))
                        DBG(CXT, ul_debugobj(cxt, "      size: %ju", (uintmax_t) fdisk_partition_get_size(pa)));

                DBG(CXT, ul_debugobj(cxt,         "  defaults: start=%s, end=%s, partno=%s",
                            pa->start_follow_default ? "yes" : "no",
                            pa->end_follow_default ? "yes" : "no",
                            pa->partno_follow_default ? "yes" : "no"));
        } else
                DBG(CXT, ul_debugobj(cxt, "adding partition"));

        rc = cxt->label->op->add_part(cxt, pa, partno);

        DBG(CXT, ul_debugobj(cxt, "add partition done (rc=%d)", rc));
        return rc;
}

/**
 * fdisk_delete_partition:
 * @cxt: fdisk context
 * @partno: partition number to delete (0 is the first partition)
 *
 * Deletes a @partno partition from disklabel.
 *
 * Returns: 0 on success, <0 on error
 */
int fdisk_delete_partition(struct fdisk_context *cxt, size_t partno)
{
        if (!cxt || !cxt->label)
                return -EINVAL;
        if (!cxt->label->op->del_part)
                return -ENOSYS;

        fdisk_wipe_partition(cxt, partno, 0);

        DBG(CXT, ul_debugobj(cxt, "deleting %s partition number %zd",
                                cxt->label->name, partno));
        return cxt->label->op->del_part(cxt, partno);
}

/**
 * fdisk_delete_all_partitions:
 * @cxt: fdisk context
 *
 * Delete all used partitions from disklabel.
 *
 * Returns: 0 on success, otherwise, a corresponding error.
 */
int fdisk_delete_all_partitions(struct fdisk_context *cxt)
{
        size_t i;
        int rc = 0;

        if (!cxt || !cxt->label)
                return -EINVAL;

        for (i = 0; i < cxt->label->nparts_max; i++) {

                if (!fdisk_is_partition_used(cxt, i))
                        continue;
                rc = fdisk_delete_partition(cxt, i);
                if (rc)
                        break;
        }

        return rc;
}

/**
 * fdisk_is_partition_used:
 * @cxt: context
 * @n: partition number (0 is the first partition)
 *
 * Check if the partition number @n is used by partition table. This function
 * does not check if the device is used (e.g. mounted) by system!
 *
 * This is faster than fdisk_get_partition() + fdisk_partition_is_used().
 *
 * Returns: 0 or 1
 */
int fdisk_is_partition_used(struct fdisk_context *cxt, size_t n)
{
        if (!cxt || !cxt->label)
                return -EINVAL;
        if (!cxt->label->op->part_is_used)
                return -ENOSYS;

        return cxt->label->op->part_is_used(cxt, n);
}