Add function that returns the library version.

libdm/libdevmapper.h

@@ -66,6 +66,7 @@ struct dm_info {
 	unsigned int target_count;
 };
 
+int dm_get_library_version(char *version, size_t size);
 int dm_task_get_driver_version(struct dm_task *dmt, char *version, size_t size);
 int dm_task_get_info(struct dm_task *dmt, struct dm_info *dmi);
 

libdm/libdm-common.c

@@ -58,6 +58,12 @@ void _build_dev_path(char *buffer, size_t len, const char *dev_name)
         	snprintf(buffer, len, "%s/%s", _dm_dir, dev_name);
 }
 
+int dm_get_library_version(char *version, size_t size)
+{
+	strncpy(version, DM_LIB_VERSION, size);
+	return 1;
+}
+
 struct dm_task *dm_task_create(int type)
 {
         struct dm_task *dmt = malloc(sizeof(*dmt));

libdm/libdm-common.h.in

@@ -14,3 +14,5 @@ extern struct target *create_target(uint64_t start,
 int add_dev_node(const char *dev_name, dev_t dev);
 int rm_dev_node(const char *dev_name);
 
+#define DM_LIB_VERSION @DM_LIB_VERSION@
+

tools/dmsetup.c

@@ -162,6 +162,9 @@ static int _version(int argc, char **argv)
 	struct dm_task *dmt;
 	char version[80];
 
+	if (dm_get_library_version(version, sizeof(version)))
+		printf("Library version:   %s\n", version);
+
 	if (!(dmt = dm_task_create(DM_DEVICE_VERSION)))
 		return 0;