make: config -- Add testing if we have libbsd installed

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile.config

@@ -3,6 +3,11 @@ include scripts/feature-tests.mak
 
 CONFIG		:= include/config.h
 
+ifeq ($(call try-cc,$(LIBBSD_DEV_TEST),-lbsd),y)
+	LIBS += -lbsd
+	DEFINES += -DCONFIG_HAS_LIBBSD
+endif
+
 $(CONFIG): scripts/utilities.mak scripts/feature-tests.mak include/config-base.h
 	$(E) "  GEN     " $@
 	$(Q) @echo '#ifndef __CR_CONFIG_H__' > $@
@@ -16,10 +21,10 @@ endif
 ifeq ($(call try-cc,$(PRLIMIT_TEST),),y)
 	$(Q) @echo '#define CONFIG_HAS_PRLIMIT' >> $@
 endif
-ifeq ($(call try-cc,$(STRLCPY_TEST),),y)
+ifeq ($(call try-cc,$(STRLCPY_TEST),$(LIBS)),y)
 	$(Q) @echo '#define CONFIG_HAS_STRLCPY' >> $@
 endif
-ifeq ($(call try-cc,$(STRLCAT_TEST),),y)
+ifeq ($(call try-cc,$(STRLCAT_TEST),$(LIBS)),y)
 	$(Q) @echo '#define CONFIG_HAS_STRLCAT' >> $@
 endif
 ifeq ($(call try-cc,$(PTRACE_PEEKSIGINFO_TEST),),y)

include/string.h

@@ -4,6 +4,10 @@
 #include <sys/types.h>
 #include <string.h>
 
+#ifdef CONFIG_HAS_LIBBSD
+# include <bsd/string.h>
+#endif
+
 #include "config.h"
 
 #ifndef CONFIG_HAS_STRLCPY

scripts/feature-tests.mak

@@ -30,10 +30,23 @@ int main(void)
 }
 endef
 
+define LIBBSD_DEV_TEST
+#include <bsd/string.h>
+
+int main(void)
+{
+	return 0;
+}
+endef
+
 define STRLCPY_TEST
 
 #include <string.h>
 
+#ifdef CONFIG_HAS_LIBBSD
+# include <bsd/string.h>
+#endif
+
 int main(void)
 {
 	return strlcpy(NULL, NULL, 0);
@@ -44,6 +57,10 @@ define STRLCAT_TEST
 
 #include <string.h>
 
+#ifdef CONFIG_HAS_LIBBSD
+# include <bsd/string.h>
+#endif
+
 int main(void)
 {
 	return strlcat(NULL, NULL, 0);