Add lvm_library_get_version() and update unit tests to display version.

liblvm/.exported_symbols

@@ -1,3 +1,4 @@
+lvm_library_get_version
 lvm_init
 lvm_quit
 lvm_config_reload

liblvm/lvm.h

@@ -28,6 +28,20 @@
  */
 /******************************** WARNING ********************************/
 
+/**
+ * Retrieve the library version.
+ *
+ * The library version is the same format as the full LVM version.
+ * The format is as follows:
+ *    LVM_MAJOR.LVM_MINOR.LVM_PATCHLEVEL(LVM_LIBAPI)[-LVM_RELEASE]
+ * An application wishing to determine compatibility with a particular version
+ * of the library should check at least the LVM_MAJOR, LVM_MINOR, and
+ * LVM_LIBAPI numbers.  For example, assume the full LVM version is
+ * 2.02.50(1)-1.  The application should verify the "2.02" and the "(1)".
+ *
+ * \return  A string describing the library version.
+ */
+const char *lvm_library_get_version(void);
 
 /******************************** structures ********************************/
 

liblvm/lvm_base.c

@@ -17,6 +17,11 @@
 #include "toolcontext.h"
 #include "locking.h"
 
+const char *lvm_library_get_version(void)
+{
+	return LVM_VERSION;
+}
+
 lvm_t lvm_init(const char *system_dir)
 {
 	struct cmd_context *cmd;

test/api/test.c

@@ -607,6 +607,7 @@ int main (int argc, char *argv[])
 		return 1;
 	}
 
+	printf("Library version: %s\n", lvm_library_get_version());
 	lvmapi_test_shell(libh);
 
 	lvm_quit(libh);

test/api/vgtest.c

@@ -96,6 +96,7 @@ int main(int argc, char *argv[])
 		goto bad;
 	}
 
+	printf("Library version: %s\n", lvm_library_get_version());
 	vg_create(vg_name);
 	vg_extend(vg, device);