3 files changed, 26 insertions, 1 deletions
diff --git a/libc/stdio/vdprintf.c b/libc/stdio/vdprintf.c
index 94ed6b8b8..6e28b14c0 100644
--- a/libc/stdio/vdprintf.c
+++ b/libc/stdio/vdprintf.c
@@ -11,6 +11,9 @@
 #include "_stdio.h"
 #include <stdarg.h>
 
+#ifdef __USE_OLD_VFPRINTF__
+libc_hidden_proto(vfprintf)
+#endif
 libc_hidden_proto(fflush_unlocked)
 
 libc_hidden_proto(vdprintf)
@@ -49,13 +52,17 @@ int vdprintf(int filedes, const char * __restrict format, va_list arg)
 
 /* _vfprintf_internal doesn't do any locking, locking init is here
  * only because of fflush_unlocked. TODO? */
-#ifdef __UCLIBC_HAS_THREADS__
+#if (defined(__STDIO_BUFFERS) || defined(__USE_OLD_VFPRINTF__)) && defined(__UCLIBC_HAS_THREADS__)
 	f.__user_locking = 1;		/* Set user locking. */
 	__stdio_init_mutex(&f.__lock);
 #endif
 	f.__nextopen = NULL;
 
+#ifdef __USE_OLD_VFPRINTF__
+	rv = vfprintf(&f, format, arg);
+#else
 	rv = _vfprintf_internal(&f, format, arg);
+#endif
 
 #ifdef __STDIO_BUFFERS
 	/* If not buffering, then fflush is unnecessary. */
diff --git a/libc/stdio/vsnprintf.c b/libc/stdio/vsnprintf.c
index 132959dcf..b54d54d20 100644
--- a/libc/stdio/vsnprintf.c
+++ b/libc/stdio/vsnprintf.c
@@ -10,12 +10,18 @@
 
 libc_hidden_proto(vsnprintf)
 
+#ifdef __USE_OLD_VFPRINTF__
+libc_hidden_proto(vfprintf)
+#endif
+
 #ifdef __UCLIBC_MJN3_ONLY__
 #warning WISHLIST: Implement vsnprintf for non-buffered and no custom stream case.
 #endif /* __UCLIBC_MJN3_ONLY__ */
 
 #ifdef __STDIO_BUFFERS
 
+/* NB: __USE_OLD_VFPRINTF__ is not defined in this case */
+
 int vsnprintf(char *__restrict buf, size_t size,
 			  const char * __restrict format, va_list arg)
 {
diff --git a/libc/stdio/vswprintf.c b/libc/stdio/vswprintf.c
index f80bb5f64..59f7c2b57 100644
--- a/libc/stdio/vswprintf.c
+++ b/libc/stdio/vswprintf.c
@@ -11,6 +11,10 @@
 
 libc_hidden_proto(vswprintf)
 
+#ifdef __USE_OLD_VFPRINTF__
+libc_hidden_proto(vfwprintf)
+#endif
+
 #ifndef __STDIO_BUFFERS
 #warning Skipping vswprintf since no buffering!
 #else  /* __STDIO_BUFFERS */
@@ -38,6 +42,10 @@ int vswprintf(wchar_t *__restrict buf, size_t size,
 	__INIT_MBSTATE(&(f.__state));
 #endif /* __STDIO_MBSTATE */
 
+#if defined(__USE_OLD_VFPRINTF__) && defined(__UCLIBC_HAS_THREADS__)
+	f.__user_locking = 1;		/* Set user locking. */
+	__stdio_init_mutex(&f.__lock);
+#endif
 	f.__nextopen = NULL;
 
 	if (size > ((SIZE_MAX - (size_t) buf)/sizeof(wchar_t))) {
@@ -50,7 +58,11 @@ int vswprintf(wchar_t *__restrict buf, size_t size,
 	__STDIO_STREAM_DISABLE_GETC(&f);
 	__STDIO_STREAM_DISABLE_PUTC(&f);
 
+#ifdef __USE_OLD_VFPRINTF__
+	rv = vfwprintf(&f, format, arg);
+#else
 	rv = _vfwprintf_internal(&f, format, arg);
+#endif
 
 	/* NOTE: Return behaviour differs from snprintf... */
 	if (f.__bufpos == f.__bufend) {