[PATCH 18/20] lib/cobalt: Finally build the native time_t interfaces on top

libcobalt was by default providing the time64_t based interfaces in
case time64_t (or y2038) support has been enabled.

We now separated all affected services into a separate compile unit
that allows us to build this compile unit twice. Once with and once
without time64_t support. With that we can build the native interfaces
on top.

libcobalt can now provide both interfaces at the same time. That should
improve backward compatibility a bit.

Signed-off-by: Florian Bezdeka <[email protected]>
---
 include/cobalt/wrappers.h | 13 ++++++-------
 lib/cobalt/Makefile.am    | 19 +++++++++++++++++++
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/include/cobalt/wrappers.h b/include/cobalt/wrappers.h
index a5645a1d48946c47bb117064589e883a250839a7..6d826eedf25c5f7708c4a88532101904fb60cd80 100644
--- a/include/cobalt/wrappers.h
+++ b/include/cobalt/wrappers.h
@@ -34,13 +34,12 @@
  * Make __RT() and __STD() usable in combination with time64_t related services.
  */
 #define COBALT_IMPL_TIME64(T, FN, FN_64, I)                                    \
-	__typeof__(T) __wrap_##FN_64 I                                         \
-		__attribute__((alias("__cobalt_" __stringify(FN)), weak));     \
-	COBALT_IMPL(T, FN, I)
-#define COBALT_DECL_TIME64(T, FN, A, I)                                        \
-	__typeof__(T) __STD(A) I;                                              \
-	extern T __REDIRECT_NTH(__STD(FN), I, __real_##A);                     \
-	COBALT_DECL(T, FN, I)
+	COBALT_IMPL(T, FN_64, I)
+#define COBALT_DECL_TIME64(T, FN, FN_64, I)                                    \
+	COBALT_DECL(T, FN_64, I);                                              \
+	extern T __REDIRECT_NTH(__STD(FN), I, __real_##FN_64);                 \
+	extern T __REDIRECT_NTH(__RT(FN), I, __cobalt_##FN_64);                \
+	extern T __REDIRECT_NTH(__WRAP(FN), I, __wrap_##FN_64)
 #else
 #define COBALT_IMPL_TIME64(T, FN, FN_64, I) COBALT_IMPL(T, FN, I)
 #define COBALT_DECL_TIME64(T, FN, FN_64, I) COBALT_DECL(T, FN, I)
diff --git a/lib/cobalt/Makefile.am b/lib/cobalt/Makefile.am
index c31f030117dfc3ddf5ae386897fbc8a2435912a8..697c6ab9fcad8625e0fe604ee027309e992042f3 100644
--- a/lib/cobalt/Makefile.am
+++ b/lib/cobalt/Makefile.am
@@ -62,6 +62,25 @@ libcobaltext_la_CPPFLAGS =		\
 	-I$(top_srcdir)/include		\
 	-U_TIME_BITS -U_FILE_OFFSET_BITS
 
+if CONFIG_XENO_LIBS_TIME64
+# If time64_t has ben requested libcobalt is already providing time64_t
+# interfaces. The native interfaces have to be build on top.
+libcobaltnativetime_la_SOURCES =	\
+	wrappers.c			\
+	wrappers_time64.c
+
+libcobaltnativetime_la_LDFLAGS = @XENO_LIB_LDFLAGS@
+
+libcobaltnativetime_la_CPPFLAGS =	\
+	@XENO_COBALT_CFLAGS@		\
+        -I$(top_srcdir)/include/cobalt	\
+        -I$(top_srcdir)/include		\
+        -U_TIME_BITS -U_FILE_OFFSET_BITS
+
+noinst_LTLIBRARIES += libcobaltnativetime.la
+libcobalt_la_LIBADD += libcobaltnativetime.la
+endif
+
 libmodechk_la_LIBADD = libcobalt.la
 
 libmodechk_la_SOURCES =	\

-- 
2.53.0