libfdisk: add table container

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 149 insertions, 0 deletions

diff --git a/libfdisk/src/table.c b/libfdisk/src/table.c
new file mode 100644
index 000000000..34d8fbb8c
--- /dev/null
+++ b/libfdisk/src/table.c
@@ -0,0 +1,149 @@
+
+#include "fdiskP.h"
+
+/**
+ * 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, dbgprint("alloc"));
+	tb->refcount = 1;
+	INIT_LIST_HEAD(&tb->parts);
+	return tb;
+}
+
+/**
+ * fdisk_reset_table:
+ * @tb: tab pointer
+ *
+ * Removes all entries (filesystems) from the table. The filesystems with zero
+ * reference count will be deallocated.
+ *
+ * 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, dbgprint("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);
+	}
+
+	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 by fdisk_free_table().
+ */
+void fdisk_unref_table(struct fdisk_table *tb)
+{
+	if (!tb)
+		return;
+
+	tb->refcount--;
+	if (tb->refcount <= 0) {
+		fdisk_reset_table(tb);
+
+		DBG(TAB, dbgprint("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)
+{
+	assert(tb);
+	return tb == NULL || list_empty(&tb->parts) ? 1 : 0;
+}
+
+/**
+ * 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);
+
+	DBG(TAB, dbgprint("add entry %p", pa));
+	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, dbgprint("remove entry %p", pa));
+	list_del(&pa->parts);
+	INIT_LIST_HEAD(&pa->parts);
+
+	fdisk_unref_partition(pa);
+	return 0;
+}