Add lvm_list_vg_names and lvm_list_vg_ids liblvm functions.

These functions provide the capability of enumerating all vgnames and
vgids in the system.  They do not do a scan of the system.

Author: Dave Wysochanski <dwysocha@redhat.com>

3 files changed, 43 insertions, 0 deletions

diff --git a/liblvm/.exported_symbols b/liblvm/.exported_symbols
index cb1319c4..c652625e 100644
--- a/liblvm/.exported_symbols
+++ b/liblvm/.exported_symbols
@@ -18,3 +18,5 @@ lvm_errno
 lvm_errmsg
 lvm_vg_list_pvs
 lvm_vg_list_lvs
+lvm_list_vg_names
+lvm_list_vg_ids
diff --git a/liblvm/lvm.h b/liblvm/lvm.h
index ba2077c8..2897fc0a 100644
--- a/liblvm/lvm.h
+++ b/liblvm/lvm.h
@@ -44,6 +44,11 @@ typedef struct lvm_lv_list {
 	lv_t *lv;
 } lv_list_t;
 
+struct lvm_str_list {
+	struct dm_list list;
+	const char *str;
+};
+
 /**
  * Return a list of LV handles for a given VG handle.
  *
@@ -256,4 +261,30 @@ vg_t *lvm_vg_open(lvm_t libh, const char *vgname, const char *mode,
  */
 struct dm_list *lvm_vg_list_pvs(vg_t *vg);
 
+/**
+ * Return a list of VG names or VG uuids in the system.
+ *
+ * NOTE: This function will _NOT_ scan devices in the system for LVM metadata.
+ * To process the list, use the dm_list iterator functions.  For example:
+ *      vg_t *vg;
+ *      struct dm_list *vgnames;
+ *      struct lvm_str_list *strl;
+ *
+ *      vgnames = lvm_list_vg_names(libh);
+ *	dm_list_iterate_items(strl, vgnames) {
+ *		vgname = strl->str;
+ *              vg = lvm_vg_open(libh, vgname, "r");
+ *              // do something with vg
+ *              lvm_vg_close(vg);
+ *      }
+ *
+ *
+ * \return  A list of struct lvm_str_list
+ *          If no VGs exist on the system, NULL is returned.
+ * FIXME: handle list memory cleanup
+ */
+struct dm_list *lvm_list_vg_names(lvm_t libh);
+struct dm_list *lvm_list_vg_ids(lvm_t libh);
+
+
 #endif /* _LIB_LVM_H */
diff --git a/liblvm/lvm_vg.c b/liblvm/lvm_vg.c
index 052f446c..44120921 100644
--- a/liblvm/lvm_vg.c
+++ b/liblvm/lvm_vg.c
@@ -188,3 +188,13 @@ char *lvm_vg_get_name(const vg_t *vg)
 	name[NAME_LEN] = '\0';
 	return name;
 }
+
+struct dm_list *lvm_list_vg_names(lvm_t libh)
+{
+	return get_vgnames((struct cmd_context *)libh, 0);
+}
+
+struct dm_list *lvm_list_vg_ids(lvm_t libh)
+{
+	return get_vgids((struct cmd_context *)libh, 0);
+}