Conditionalize temporary compatibility inclusions

These inclusions were in place for backward compatibility purposes,
when the headers were split so that code using them would not break.
Make it possible for applications to disable them by defining
LIBBSD_CLEAN_INCLUDES so that buildability can be tested and fixed
before they get removed in a subsequent release.

Makefile

@@ -125,7 +125,9 @@ CFLAGS ?= -g -Wall -Wextra -Wno-unused-variable
 LDFLAGS ?=
 
 # Internal makefile variables
-MK_CPPFLAGS := -Iinclude/bsd/ -Iinclude/ -DLIBBSD_TRANSPARENT -D_GNU_SOURCE -D__REENTRANT
+MK_CPPFLAGS := -Iinclude/bsd/ -Iinclude/ \
+	-DLIBBSD_TRANSPARENT -DLIBBSD_CLEAN_INCLUDES \
+	-D_GNU_SOURCE -D__REENTRANT
 MK_CFLAGS :=
 MK_LDFLAGS :=
 

include/bsd/stdlib.h

@@ -47,8 +47,10 @@
 #endif
 
 /* FIXME: Temporary inclusions to avoid API breakage, will be removed soon. */
+#ifndef LIBBSD_CLEAN_INCLUDES
 #include <bsd/stdio.h>
 #include <bsd/unistd.h>
+#endif
 
 __BEGIN_DECLS
 u_int32_t arc4random();

include/bsd/string.h

@@ -36,8 +36,10 @@
 #include <string.h>
 #endif
 
+#ifndef LIBBSD_CLEAN_INCLUDES
 /* FIXME: Temporary inclusion to avoid API breakage, will be removed soon. */
 #include <bsd/stdio.h>
+#endif
 
 __BEGIN_DECLS
 size_t strlcpy(char *dst, const char *src, size_t siz);

src/vis.c

@@ -32,6 +32,7 @@
 #include <limits.h>
 #include <ctype.h>
 #include <string.h>
+#include <stdio.h>
 #include <vis.h>
 
 #define	isoctal(c)	(((u_char)(c)) >= '0' && ((u_char)(c)) <= '7')