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-rw-r--r--libblkid/libfdisk/src/table.c664
1 files changed, 664 insertions, 0 deletions
diff --git a/libblkid/libfdisk/src/table.c b/libblkid/libfdisk/src/table.c
new file mode 100644
index 000000000..1add09fca
--- /dev/null
+++ b/libblkid/libfdisk/src/table.c
@@ -0,0 +1,664 @@
+
+#include "fdiskP.h"
+
+/**
+ * SECTION: table
+ * @title: Table
+ * @short_description: container for fdisk partitions
+ *
+ * The fdisk_table is simple container for fdisk_partitions. The table is no
+ * directly connected to label data (partition table), and table changes don't
+ * affect in-memory or on-disk data.
+ */
+
+/**
+ * fdisk_new_table:
+ *
+ * The table is a container for struct fdisk_partition entries. The container
+ * does not have any real connection with label (partition table) and with
+ * real on-disk data.
+ *
+ * Returns: newly allocated table struct.
+ */
+struct fdisk_table *fdisk_new_table(void)
+{
+ struct fdisk_table *tb = NULL;
+
+ tb = calloc(1, sizeof(*tb));
+ if (!tb)
+ return NULL;
+
+ DBG(TAB, ul_debugobj(tb, "alloc"));
+ tb->refcount = 1;
+ INIT_LIST_HEAD(&tb->parts);
+ return tb;
+}
+
+/**
+ * fdisk_reset_table:
+ * @tb: tab pointer
+ *
+ * Removes all entries (partitions) from the table. The parititons with zero
+ * reference count will be deallocated. This function does not modify partition
+ * table.
+ *
+ * Returns: 0 on success or negative number in case of error.
+ */
+int fdisk_reset_table(struct fdisk_table *tb)
+{
+ if (!tb)
+ return -EINVAL;
+
+ DBG(TAB, ul_debugobj(tb, "reset"));
+
+ while (!list_empty(&tb->parts)) {
+ struct fdisk_partition *pa = list_entry(tb->parts.next,
+ struct fdisk_partition, parts);
+ fdisk_table_remove_partition(tb, pa);
+ }
+
+ tb->nents = 0;
+ return 0;
+}
+
+/**
+ * fdisk_ref_table:
+ * @tb: table pointer
+ *
+ * Incremparts reference counter.
+ */
+void fdisk_ref_table(struct fdisk_table *tb)
+{
+ if (tb)
+ tb->refcount++;
+}
+
+/**
+ * fdisk_unref_table:
+ * @tb: table pointer
+ *
+ * De-incremparts reference counter, on zero the @tb is automatically
+ * deallocated.
+ */
+void fdisk_unref_table(struct fdisk_table *tb)
+{
+ if (!tb)
+ return;
+
+ tb->refcount--;
+ if (tb->refcount <= 0) {
+ fdisk_reset_table(tb);
+
+ DBG(TAB, ul_debugobj(tb, "free"));
+ free(tb);
+ }
+}
+
+/**
+ * fdisk_table_is_empty:
+ * @tb: pointer to tab
+ *
+ * Returns: 1 if the table is without filesystems, or 0.
+ */
+int fdisk_table_is_empty(struct fdisk_table *tb)
+{
+ return tb == NULL || list_empty(&tb->parts) ? 1 : 0;
+}
+
+/**
+ * fdisk_table_get_nents:
+ * @tb: pointer to tab
+ *
+ * Returns: number of entries in table.
+ */
+size_t fdisk_table_get_nents(struct fdisk_table *tb)
+{
+ return tb ? tb->nents : 0;
+}
+
+/**
+ * fdisk_table_next_partition:
+ * @tb: tab pointer
+ * @itr: iterator
+ * @pa: returns the next tab entry
+ *
+ * Returns: 0 on success, negative number in case of error or 1 at the end of list.
+ *
+ * Example:
+ * <informalexample>
+ * <programlisting>
+ * while(fdisk_table_next_partition(tb, itr, &pa) == 0) {
+ * ...
+ * }
+ * </programlisting>
+ * </informalexample>
+ */
+int fdisk_table_next_partition(
+ struct fdisk_table *tb,
+ struct fdisk_iter *itr,
+ struct fdisk_partition **pa)
+{
+ int rc = 1;
+
+ assert(tb);
+ assert(itr);
+ assert(pa);
+
+ if (!tb || !itr || !pa)
+ return -EINVAL;
+ *pa = NULL;
+
+ if (!itr->head)
+ FDISK_ITER_INIT(itr, &tb->parts);
+ if (itr->p != itr->head) {
+ FDISK_ITER_ITERATE(itr, *pa, struct fdisk_partition, parts);
+ rc = 0;
+ }
+
+ return rc;
+}
+
+struct fdisk_partition *fdisk_table_get_partition(
+ struct fdisk_table *tb,
+ size_t n)
+{
+ struct fdisk_partition *pa = NULL;
+ struct fdisk_iter itr;
+
+ if (!tb)
+ return NULL;
+
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+
+ while (fdisk_table_next_partition(tb, &itr, &pa) == 0) {
+ if (n == 0)
+ return pa;
+ n--;
+ }
+
+ return NULL;
+}
+
+/**
+ * fdisk_table_add_partition
+ * @tb: tab pointer
+ * @pa: new entry
+ *
+ * Adds a new entry to table and increment @pa reference counter. Don't forget to
+ * use fdisk_unref_pa() after fdisk_table_add_partition() if you want to keep
+ * the @pa referenced by the table only.
+ *
+ * Returns: 0 on success or negative number in case of error.
+ */
+int fdisk_table_add_partition(struct fdisk_table *tb, struct fdisk_partition *pa)
+{
+ assert(tb);
+ assert(pa);
+
+ if (!tb || !pa)
+ return -EINVAL;
+
+ fdisk_ref_partition(pa);
+ list_add_tail(&pa->parts, &tb->parts);
+ tb->nents++;
+
+ DBG(TAB, ul_debugobj(tb, "add entry %p [start=%ju, end=%ju, size=%ju, %s %s %s]",
+ 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" : "primary"));
+ return 0;
+}
+
+/* inserts @pa after @poz */
+static int table_insert_partition(
+ struct fdisk_table *tb,
+ struct fdisk_partition *poz,
+ struct fdisk_partition *pa)
+{
+ assert(tb);
+ assert(pa);
+
+ fdisk_ref_partition(pa);
+ if (poz)
+ list_add(&pa->parts, &poz->parts);
+ else
+ list_add(&pa->parts, &tb->parts);
+ tb->nents++;
+
+ DBG(TAB, ul_debugobj(tb, "insert entry %p pre=%p [start=%ju, end=%ju, size=%ju, %s %s %s]",
+ pa, poz ? poz : NULL,
+ (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" : ""));
+ return 0;
+}
+
+/**
+ * fdisk_table_remove_partition
+ * @tb: tab pointer
+ * @pa: new entry
+ *
+ * Removes the @pa from the table and de-increment reference counter of the @pa. The
+ * partition with zero reference counter will be deallocated. Don't forget to use
+ * fdisk_ref_partition() before call fdisk_table_remove_partition() if you want
+ * to use @pa later.
+ *
+ * Returns: 0 on success or negative number in case of error.
+ */
+int fdisk_table_remove_partition(struct fdisk_table *tb, struct fdisk_partition *pa)
+{
+ assert(tb);
+ assert(pa);
+
+ if (!tb || !pa)
+ return -EINVAL;
+
+ DBG(TAB, ul_debugobj(tb, "remove entry %p", pa));
+ list_del(&pa->parts);
+ INIT_LIST_HEAD(&pa->parts);
+
+ fdisk_unref_partition(pa);
+ tb->nents--;
+
+ return 0;
+}
+
+/**
+ * fdisk_get_partitions
+ * @cxt: fdisk context
+ * @tb: returns table
+ *
+ * This function adds partitions from disklabel to @table, it allocates a new
+ * table if if @table points to NULL.
+ *
+ * Returns: 0 on success, otherwise, a corresponding error.
+ */
+int fdisk_get_partitions(struct fdisk_context *cxt, struct fdisk_table **tb)
+{
+ size_t i;
+
+ if (!cxt || !cxt->label || !tb)
+ return -EINVAL;
+ if (!cxt->label->op->get_part)
+ return -ENOSYS;
+
+ DBG(CXT, ul_debugobj(cxt, "get table"));
+
+ if (!*tb && !(*tb = fdisk_new_table()))
+ return -ENOMEM;
+
+ for (i = 0; i < cxt->label->nparts_max; i++) {
+ struct fdisk_partition *pa = NULL;
+
+ if (fdisk_get_partition(cxt, i, &pa) != 0)
+ continue;
+ if (fdisk_partition_is_used(pa))
+ fdisk_table_add_partition(*tb, pa);
+ fdisk_unref_partition(pa);
+ }
+
+ return 0;
+}
+
+static void debug_print_table(struct fdisk_table *tb)
+{
+ struct fdisk_iter itr;
+ struct fdisk_partition *pa;
+
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ while (fdisk_table_next_partition(tb, &itr, &pa) == 0)
+ ul_debugobj(tb, "partition %p [partno=%zu, start=%ju, end=%ju, size=%ju] ",
+ pa, pa->partno,
+ (uintmax_t) fdisk_partition_get_start(pa),
+ (uintmax_t) fdisk_partition_get_end(pa),
+ (uintmax_t) fdisk_partition_get_size(pa));
+
+}
+
+
+typedef int (*fdisk_partcmp_t)(struct fdisk_partition *, struct fdisk_partition *);
+
+static int cmp_parts_wrapper(struct list_head *a, struct list_head *b, void *data)
+{
+ struct fdisk_partition *pa = list_entry(a, struct fdisk_partition, parts),
+ *pb = list_entry(b, struct fdisk_partition, parts);
+
+ fdisk_partcmp_t cmp = (fdisk_partcmp_t) data;
+
+ return cmp(pa, pb);
+}
+
+
+/**
+ * fdisk_table_sort_partitions:
+ * @tb: table
+ * @cmp: compare function
+ *
+ * Sort partition in the table.
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int fdisk_table_sort_partitions(struct fdisk_table *tb,
+ int (*cmp)(struct fdisk_partition *,
+ struct fdisk_partition *))
+{
+ if (!tb)
+ return -EINVAL;
+
+ DBG(TAB, ul_debugobj(tb, "Before sort:"));
+ ON_DBG(TAB, debug_print_table(tb));
+
+ list_sort(&tb->parts, cmp_parts_wrapper, (void *) cmp);
+
+ DBG(TAB, ul_debugobj(tb, "After sort:"));
+ ON_DBG(TAB, debug_print_table(tb));
+
+ return 0;
+}
+
+/* allocates a new freespace description */
+static int new_freespace(struct fdisk_context *cxt,
+ fdisk_sector_t start,
+ fdisk_sector_t end,
+ struct fdisk_partition *parent,
+ struct fdisk_partition **pa)
+{
+ assert(cxt);
+ assert(pa);
+
+ *pa = NULL;
+
+ if (start == end)
+ return 0;
+ *pa = fdisk_new_partition();
+ if (!*pa)
+ return -ENOMEM;
+
+ assert(start);
+ assert(end);
+ assert(end > start);
+
+ (*pa)->freespace = 1;
+ (*pa)->start = fdisk_align_lba_in_range(cxt, start, start, end);
+ (*pa)->size = end - (*pa)->start + 1ULL;
+
+ if (parent)
+ (*pa)->parent_partno = parent->partno;
+ return 0;
+}
+
+/* add freespace description to the right place within @tb */
+static int table_add_freespace(
+ struct fdisk_context *cxt,
+ struct fdisk_table *tb,
+ fdisk_sector_t start,
+ fdisk_sector_t end,
+ struct fdisk_partition *parent)
+{
+ struct fdisk_partition *pa, *x, *real_parent = NULL, *best = NULL;
+ struct fdisk_iter itr;
+ int rc = 0;
+
+ assert(tb);
+
+ rc = new_freespace(cxt, start, end, parent, &pa);
+ if (rc)
+ return -ENOMEM;
+ if (!pa)
+ return 0;
+
+ assert(fdisk_partition_has_start(pa));
+ assert(fdisk_partition_has_end(pa));
+
+ DBG(TAB, ul_debugobj(tb, "adding freespace"));
+
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ if (parent && fdisk_partition_has_partno(parent)) {
+ while (fdisk_table_next_partition(tb, &itr, &x) == 0) {
+ if (!fdisk_partition_has_partno(x))
+ continue;
+ if (x->partno == parent->partno) {
+ real_parent = x;
+ break;
+ }
+ }
+ if (!real_parent) {
+ DBG(TAB, ul_debugobj(tb, "not found freespace parent (partno=%zu)",
+ parent->partno));
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ }
+ }
+
+ while (fdisk_table_next_partition(tb, &itr, &x) == 0) {
+ fdisk_sector_t end, best_end = 0;
+
+ if (!fdisk_partition_has_end(x))
+ continue;
+
+ end = fdisk_partition_get_end(x);
+ if (best)
+ best_end = fdisk_partition_get_end(best);
+
+ if (end < pa->start && (!best || best_end < end))
+ best = x;
+ }
+
+ if (!best && real_parent)
+ best = real_parent;
+ rc = table_insert_partition(tb, best, pa);
+
+ fdisk_unref_partition(pa);
+
+ DBG(TAB, ul_debugobj(tb, "adding freespace DONE [rc=%d]", rc));
+ return rc;
+}
+
+/* analyze @cont(ainer) in @parts and add all detected freespace into @tb, note
+ * that @parts has to be sorted by partition starts */
+static int check_container_freespace(struct fdisk_context *cxt,
+ struct fdisk_table *parts,
+ struct fdisk_table *tb,
+ struct fdisk_partition *cont)
+{
+ struct fdisk_iter itr;
+ struct fdisk_partition *pa;
+ fdisk_sector_t x, last, grain, lastplusoff;
+ int rc = 0;
+
+ assert(cxt);
+ assert(parts);
+ assert(tb);
+ assert(cont);
+ assert(fdisk_partition_has_start(cont));
+
+ DBG(TAB, ul_debugobj(tb, "analyze container 0x%p", cont));
+
+ last = fdisk_partition_get_start(cont);
+ grain = cxt->grain > cxt->sector_size ? cxt->grain / cxt->sector_size : 1;
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+
+ DBG(CXT, ul_debugobj(cxt, "initialized: last=%ju, grain=%ju", last, grain));
+
+ while (fdisk_table_next_partition(parts, &itr, &pa) == 0) {
+
+ DBG(CXT, ul_debugobj(cxt, "partno=%zu, start=%ju", pa->partno, pa->start));
+
+ if (!pa->used || !fdisk_partition_is_nested(pa)
+ || !fdisk_partition_has_start(pa))
+ continue;
+
+ DBG(CXT, ul_debugobj(cxt, "freespace container analyze: partno=%zu, start=%ju, end=%ju",
+ pa->partno,
+ (uintmax_t) fdisk_partition_get_start(pa),
+ (uintmax_t) fdisk_partition_get_end(pa)));
+
+ lastplusoff = last + cxt->first_lba;
+ if (pa->start > lastplusoff && pa->start - lastplusoff > grain)
+ rc = table_add_freespace(cxt, tb, lastplusoff, pa->start, cont);
+ if (rc)
+ goto done;
+ last = fdisk_partition_get_end(pa);
+ }
+
+ /* free-space remaining in extended partition */
+ x = fdisk_partition_get_start(cont) + fdisk_partition_get_size(cont) - 1;
+ lastplusoff = last + cxt->first_lba;
+ if (lastplusoff < x && x - lastplusoff > grain) {
+ DBG(TAB, ul_debugobj(tb, "add remaining space in container 0x%p", cont));
+ rc = table_add_freespace(cxt, tb, lastplusoff, x, cont);
+ }
+
+done:
+ DBG(TAB, ul_debugobj(tb, "analyze container 0x%p DONE [rc=%d]", cont, rc));
+ return rc;
+}
+
+
+/**
+ * fdisk_get_freespaces
+ * @cxt: fdisk context
+ * @tb: returns table
+ *
+ * This function adds freespace (described by fdisk_partition) to @table, it
+ * allocates a new table if the @table points to NULL.
+ *
+ * Note that free space smaller than grain (see fdisk_get_grain()) is ignored.
+
+ * Returns: 0 on success, otherwise, a corresponding error.
+ */
+int fdisk_get_freespaces(struct fdisk_context *cxt, struct fdisk_table **tb)
+{
+ int rc = 0;
+ fdisk_sector_t last, grain;
+ struct fdisk_table *parts = NULL;
+ struct fdisk_partition *pa;
+ struct fdisk_iter itr;
+
+ DBG(CXT, ul_debugobj(cxt, "get freespace"));
+
+ if (!cxt || !cxt->label || !tb)
+ return -EINVAL;
+ if (!*tb && !(*tb = fdisk_new_table()))
+ return -ENOMEM;
+
+ rc = fdisk_get_partitions(cxt, &parts);
+ if (rc)
+ goto done;
+
+ fdisk_table_sort_partitions(parts, fdisk_partition_cmp_start);
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ last = cxt->first_lba;
+ grain = cxt->grain > cxt->sector_size ? cxt->grain / cxt->sector_size : 1;
+
+ DBG(CXT, ul_debugobj(cxt, "initialized: last=%ju, grain=%ju", last, grain));
+
+ /* analyze gaps between partitions */
+ while (rc == 0 && fdisk_table_next_partition(parts, &itr, &pa) == 0) {
+
+ DBG(CXT, ul_debugobj(cxt, "partno=%zu, start=%ju", pa->partno, pa->start));
+
+ if (!pa->used || pa->wholedisk || fdisk_partition_is_nested(pa)
+ || !fdisk_partition_has_start(pa))
+ continue;
+ DBG(CXT, ul_debugobj(cxt, "freespace analyze: partno=%zu, start=%ju, end=%ju",
+ pa->partno,
+ (uintmax_t) fdisk_partition_get_start(pa),
+ (uintmax_t) fdisk_partition_get_end(pa)));
+ if (last + grain <= pa->start) {
+ rc = table_add_freespace(cxt, *tb,
+ last + (last > cxt->first_lba ? 1 : 0),
+ pa->start - 1, NULL);
+ }
+ /* add gaps between logical partitions */
+ if (fdisk_partition_is_container(pa))
+ rc = check_container_freespace(cxt, parts, *tb, pa);
+ last = fdisk_partition_get_end(pa);
+ }
+
+ /* add free-space behind last partition to the end of the table (so
+ * don't use table_add_freespace()) */
+ if (rc == 0 && last + grain < cxt->total_sectors - 1) {
+ DBG(CXT, ul_debugobj(cxt, "freespace behind last partition detected"));
+ rc = new_freespace(cxt,
+ last + (last > cxt->first_lba ? 1 : 0),
+ cxt->last_lba, NULL, &pa);
+ if (pa) {
+ fdisk_table_add_partition(*tb, pa);
+ fdisk_unref_partition(pa);
+ }
+ }
+
+done:
+ fdisk_unref_table(parts);
+
+ DBG(CXT, ul_debugobj(cxt, "get freespace DONE [rc=%d]", rc));
+ return rc;
+}
+
+/**
+ * fdisk_table_wrong_order:
+ * @tb: table
+ *
+ * Returns: 1 of the table is not in disk order
+ */
+int fdisk_table_wrong_order(struct fdisk_table *tb)
+{
+ struct fdisk_partition *pa;
+ struct fdisk_iter itr;
+ fdisk_sector_t last = 0;
+
+ DBG(TAB, ul_debugobj(tb, "wrong older check"));
+
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ while (tb && fdisk_table_next_partition(tb, &itr, &pa) == 0) {
+ if (!fdisk_partition_has_start(pa))
+ continue;
+ if (pa->start < last)
+ return 1;
+ last = pa->start;
+ }
+ return 0;
+}
+
+/**
+ * fdisk_apply_table:
+ * @cxt: context
+ * @tb: table
+ *
+ * Add partitions from table @tb to the in-memory disk label. See
+ * fdisk_add_partition(), fdisk_delete_all_partitions(). The partitons
+ * that does not define start (or does not follow the default start)
+ * are ingored.
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int fdisk_apply_table(struct fdisk_context *cxt, struct fdisk_table *tb)
+{
+ struct fdisk_partition *pa;
+ struct fdisk_iter itr;
+ int rc = 0;
+
+ assert(cxt);
+ assert(tb);
+
+ DBG(TAB, ul_debugobj(tb, "applying to context %p", cxt));
+
+ fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+ while (tb && fdisk_table_next_partition(tb, &itr, &pa) == 0) {
+ if (!fdisk_partition_has_start(pa) && !pa->start_follow_default)
+ continue;
+ rc = fdisk_add_partition(cxt, pa, NULL);
+ if (rc)
+ break;
+ }
+
+ return rc;
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 21:01:53 +0100