libblkid: add BLKID_{VERSION,DATE} to blkid.h

The original e2fsprogs has BLKID_{VERSION,DATE} macros in blkid.h.
Although the macros are not updated for many years in e2fsprogs. So I
guess nobody uses it.

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

configure.ac

@@ -330,6 +330,7 @@ AC_ARG_ENABLE([libblkid],
   AS_HELP_STRING([--disable-libblkid], [do not build libblkid and blkid utilities]),
   [], enable_libblkid=yes
 )
+AC_SUBST([LIBBLKID_DATE])
 AC_SUBST([LIBBLKID_VERSION])
 AC_SUBST([LIBBLKID_VERSION_INFO])
 AM_CONDITIONAL(BUILD_LIBBLKID, test "x$enable_libblkid" = xyes)
@@ -1022,6 +1023,7 @@ shlibs/blkid/Makefile
 shlibs/blkid/docs/Makefile
 shlibs/blkid/docs/version.xml
 shlibs/blkid/src/Makefile
+shlibs/blkid/src/blkid.h
 shlibs/blkid/src/superblocks/Makefile
 shlibs/blkid/src/topology/Makefile
 shlibs/blkid/src/partitions/Makefile

shlibs/blkid/.gitignore

@@ -2,3 +2,4 @@
 bin/blkid
 bin/findfs
 test_*
+blkid.h

shlibs/blkid/src/Makefile.am

@@ -46,7 +46,7 @@ libblkid_la_LDFLAGS = -Wl,--version-script=$(ul_libblkid_srcdir)/blkid.sym \
 tests = test_cache test_config test_dev test_devname test_devno test_getsize \
 	test_read test_resolve test_save test_tag test_verify test_evaluate
 
-EXTRA_DIST = blkid.sym tst_types.c
+EXTRA_DIST = blkid.sym tst_types.c blkid.h.in
 CLEANFILES = $(tests)
 
 tests: all $(tests)

shlibs/blkid/src/blkid.h.in

@@ -30,6 +30,9 @@
 extern "C" {
 #endif
 
+#define BLKID_VERSION   "@LIBBLKID_VERSION@"
+#define BLKID_DATE      "@LIBBLKID_DATE@"
+
 /**
  * blkid_dev:
  *

shlibs/blkid/src/version.c

@@ -22,6 +22,12 @@
 static const char *lib_version = LIBBLKID_VERSION;	/* release version */
 static const char *lib_date = LIBBLKID_DATE;
 
+/**
+ * blkid_parse_version_string:
+ * @ver_string:  version string (e.g. "2.16.0")
+ *
+ * Returns: release version code.
+ */
 int blkid_parse_version_string(const char *ver_string)
 {
 	const char *cp;