ndk: Add printf() et al to Android support library.

This adds a musl-based printf() implementation to the Android support
library. This adds support for exotic formatters like %a (hexadecimal
floats), required by the libc++ unit test suite, as found by Nico
Weber (thakis@chromium.org)

+ Add missing implementation of frexp()/frexpf()/frexpl()
  (required by vfprintf.c)

+ Minimize the differences between our vfwprintf.c implementation
  and the original musl one, by moving the output wrapper structure
  to src/stdio/stdio_impl.[hc].

BUG=36496

Change-Id: I1b8e166646f5680434e3899bbecdf9492141e4ab
diff --git a/sources/android/support/Android.mk b/sources/android/support/Android.mk
index 6b1208d..9435722 100644
--- a/sources/android/support/Android.mk
+++ b/sources/android/support/Android.mk
@@ -11,6 +11,8 @@
     src/locale/localeconv.c \
     src/locale/newlocale.c \
     src/locale/uselocale.c \
+    src/stdio/stdio_impl.c \
+    src/stdio/vfprintf.c \
     src/stdio/vfwprintf.c \
     src/musl-multibyte/btowc.c \
     src/musl-multibyte/internal.c \
@@ -97,6 +99,14 @@
     src/musl-locale/wcsxfrm_l.c \
     src/musl-locale/wctrans_l.c \
     src/musl-locale/wctype_l.c \
+    src/musl-math/frexp.c \
+    src/musl-math/frexpf.c \
+    src/musl-math/frexpl.c \
+    src/musl-stdio/printf.c \
+    src/musl-stdio/snprintf.c \
+    src/musl-stdio/sprintf.c \
+    src/musl-stdio/vprintf.c \
+    src/musl-stdio/vsprintf.c \
     src/musl-stdio/swprintf.c \
     src/musl-stdio/vwprintf.c \
     src/musl-stdio/wprintf.c \
diff --git a/sources/android/support/src/musl-math/frexp.c b/sources/android/support/src/musl-math/frexp.c
new file mode 100644
index 0000000..27b6266
--- /dev/null
+++ b/sources/android/support/src/musl-math/frexp.c
@@ -0,0 +1,23 @@
+#include <math.h>
+#include <stdint.h>
+
+double frexp(double x, int *e)
+{
+	union { double d; uint64_t i; } y = { x };
+	int ee = y.i>>52 & 0x7ff;
+
+	if (!ee) {
+		if (x) {
+			x = frexp(x*0x1p64, e);
+			*e -= 64;
+		} else *e = 0;
+		return x;
+	} else if (ee == 0x7ff) {
+		return x;
+	}
+
+	*e = ee - 0x3fe;
+	y.i &= 0x800fffffffffffffull;
+	y.i |= 0x3fe0000000000000ull;
+	return y.d;
+}
diff --git a/sources/android/support/src/musl-math/frexpf.c b/sources/android/support/src/musl-math/frexpf.c
new file mode 100644
index 0000000..0787097
--- /dev/null
+++ b/sources/android/support/src/musl-math/frexpf.c
@@ -0,0 +1,23 @@
+#include <math.h>
+#include <stdint.h>
+
+float frexpf(float x, int *e)
+{
+	union { float f; uint32_t i; } y = { x };
+	int ee = y.i>>23 & 0xff;
+
+	if (!ee) {
+		if (x) {
+			x = frexpf(x*0x1p64, e);
+			*e -= 64;
+		} else *e = 0;
+		return x;
+	} else if (ee == 0xff) {
+		return x;
+	}
+
+	*e = ee - 0x7e;
+	y.i &= 0x807ffffful;
+	y.i |= 0x3f000000ul;
+	return y.f;
+}
diff --git a/sources/android/support/src/musl-math/frexpl.c b/sources/android/support/src/musl-math/frexpl.c
new file mode 100644
index 0000000..f9d90a6
--- /dev/null
+++ b/sources/android/support/src/musl-math/frexpl.c
@@ -0,0 +1,37 @@
+#include <math.h>
+#include <stdint.h>
+#include <float.h>
+
+#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+
+/* This version is for 80-bit little endian long double */
+
+long double frexpl(long double x, int *e)
+{
+	union { long double ld; uint16_t hw[5]; } y = { x };
+	int ee = y.hw[4]&0x7fff;
+
+	if (!ee) {
+		if (x) {
+			x = frexpl(x*0x1p64, e);
+			*e -= 64;
+		} else *e = 0;
+		return x;
+	} else if (ee == 0x7fff) {
+		return x;
+	}
+
+	*e = ee - 0x3ffe;
+	y.hw[4] &= 0x8000;
+	y.hw[4] |= 0x3ffe;
+	return y.ld;
+}
+
+#else
+
+long double frexpl(long double x, int *e)
+{
+	return frexp(x, e);
+}
+
+#endif
diff --git a/sources/android/support/src/musl-stdio/printf.c b/sources/android/support/src/musl-stdio/printf.c
new file mode 100644
index 0000000..cebfe40
--- /dev/null
+++ b/sources/android/support/src/musl-stdio/printf.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include <stdarg.h>
+
+int printf(const char *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vfprintf(stdout, fmt, ap);
+	va_end(ap);
+	return ret;
+}
diff --git a/sources/android/support/src/musl-stdio/snprintf.c b/sources/android/support/src/musl-stdio/snprintf.c
new file mode 100644
index 0000000..771503b
--- /dev/null
+++ b/sources/android/support/src/musl-stdio/snprintf.c
@@ -0,0 +1,13 @@
+#include <stdio.h>
+#include <stdarg.h>
+
+int snprintf(char *restrict s, size_t n, const char *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vsnprintf(s, n, fmt, ap);
+	va_end(ap);
+	return ret;
+}
+
diff --git a/sources/android/support/src/musl-stdio/sprintf.c b/sources/android/support/src/musl-stdio/sprintf.c
new file mode 100644
index 0000000..9dff524
--- /dev/null
+++ b/sources/android/support/src/musl-stdio/sprintf.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include <stdarg.h>
+
+int sprintf(char *restrict s, const char *restrict fmt, ...)
+{
+	int ret;
+	va_list ap;
+	va_start(ap, fmt);
+	ret = vsprintf(s, fmt, ap);
+	va_end(ap);
+	return ret;
+}
diff --git a/sources/android/support/src/musl-stdio/vprintf.c b/sources/android/support/src/musl-stdio/vprintf.c
new file mode 100644
index 0000000..30d2bff
--- /dev/null
+++ b/sources/android/support/src/musl-stdio/vprintf.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int vprintf(const char *restrict fmt, va_list ap)
+{
+	return vfprintf(stdout, fmt, ap);
+}
diff --git a/sources/android/support/src/musl-stdio/vsprintf.c b/sources/android/support/src/musl-stdio/vsprintf.c
new file mode 100644
index 0000000..c57349d
--- /dev/null
+++ b/sources/android/support/src/musl-stdio/vsprintf.c
@@ -0,0 +1,7 @@
+#include <stdio.h>
+#include <limits.h>
+
+int vsprintf(char *restrict s, const char *restrict fmt, va_list ap)
+{
+	return vsnprintf(s, INT_MAX, fmt, ap);
+}
diff --git a/sources/android/support/src/stdio/stdio_impl.c b/sources/android/support/src/stdio/stdio_impl.c
new file mode 100644
index 0000000..e3c442d
--- /dev/null
+++ b/sources/android/support/src/stdio/stdio_impl.c
@@ -0,0 +1,129 @@
+#include <stdio.h>
+#include <wchar.h>
+#include <string.h>
+
+#define _STDIO_IMPL_NO_REDIRECT_MACROS
+#include "stdio_impl.h"
+
+void fake_file_init_file(FakeFILE* file, FILE* f) {
+  memset(file, 0, sizeof(*file));
+  file->file = f;
+}
+
+void fake_file_init_buffer(FakeFILE* file, char* buffer, size_t buffer_size) {
+  memset(file, 0, sizeof(*file));
+  file->buffer = buffer;
+  file->buffer_pos = 0;
+  file->buffer_size = buffer_size;
+}
+
+void fake_file_init_wbuffer(FakeFILE* file,
+                            wchar_t* buffer,
+                            size_t buffer_size) {
+  fake_file_init_buffer(file, (char*)buffer, buffer_size * sizeof(wchar_t));
+}
+
+void fake_file_out(FakeFILE* file, const char* text, size_t length) {
+  if (length == 0) {
+    // Happens pretty often, so bail immediately.
+    return;
+  }
+  if (file->file != NULL) {
+    fwrite(text, 1, length, file->file);
+  } else {
+    // Write into a bounded buffer.
+    size_t avail = file->buffer_size - file->buffer_pos;
+    if (length > avail)
+      length = avail;
+    memcpy((char*)(file->buffer + file->buffer_pos),
+           (const char*)text,
+           length);
+    file->buffer_pos += length;
+  }
+}
+
+void fake_file_outw(FakeFILE* file, const wchar_t* text, size_t length) {
+  if (length == 0)
+    return;
+  if (file->file != NULL) {
+    // Write into a file the UTF-8 encoded version.
+    // Original source calls fputwc() in a loop, which is slightly inefficient
+    // for large strings.
+    // TODO(digit): Support locale-specific encoding?
+    size_t mb_len = wcstombs(NULL, text, length);
+    char* mb_buffer = malloc(mb_len);
+    wcstombs(mb_buffer, text, length);
+    fwrite(mb_buffer, 1, mb_len, file->file);
+    free(mb_buffer);
+  } else {
+    // Write into a bounded buffer. This assumes the buffer really
+    // holds wchar_t items.
+    size_t avail = (file->buffer_size - file->buffer_pos) / sizeof(wchar_t);
+    if (length > avail)
+      length = avail;
+    memcpy((char*)(file->buffer + file->buffer_pos),
+           (const char*)text,
+           length * sizeof(wchar_t));
+    file->buffer_pos += length * sizeof(wchar_t);
+  }
+}
+
+int fake_feof(FakeFILE* file) {
+  if (file->file != NULL)
+    return feof(file->file);
+  else
+    return (file->buffer_pos >= file->buffer_size);
+}
+
+int fake_ferror(FakeFILE* file) {
+  if (file->file != NULL)
+    return ferror(file->file);
+
+  return 0;
+}
+
+int fake_fprintf(FakeFILE* file, const char* format, ...) {
+  va_list args;
+  va_start(args, format);
+  if (file->file)
+    return vfprintf(file->file, format, args);
+  else {
+    // TODO(digit): Make this faster.
+    // First, generate formatted byte output.
+    int mb_len = vsnprintf(NULL, 0, format, args);
+    char* mb_buffer = malloc(mb_len + 1);
+    vsnprintf(mb_buffer, mb_len + 1, format, args);
+    // Then convert to wchar_t buffer.
+    size_t wide_len = mbstowcs(NULL, mb_buffer, mb_len);
+    wchar_t* wide_buffer = malloc((wide_len + 1) * sizeof(wchar_t));
+    mbstowcs(wide_buffer, mb_buffer, mb_len);
+    // Add to buffer.
+    fake_file_outw(file, wide_buffer, wide_len);
+    // finished
+    free(wide_buffer);
+    free(mb_buffer);
+
+    return wide_len;
+  }
+  va_end(args);
+}
+
+void fake_fputc(char ch, FakeFILE* file) {
+  if (file->file)
+    fputc(ch, file->file);
+  else {
+    if (file->buffer_pos < file->buffer_size)
+      file->buffer[file->buffer_pos++] = ch;
+  }
+}
+
+void fake_fputwc(wchar_t wc, FakeFILE* file) {
+  if (file->file)
+    fputwc(wc, file->file);
+  else {
+    if (file->buffer_pos + sizeof(wchar_t) - 1U < file->buffer_size) {
+      *(wchar_t*)(&file->buffer[file->buffer_pos]) = wc;
+      file->buffer_pos += sizeof(wchar_t);
+    }
+  }
+}
diff --git a/sources/android/support/src/stdio/stdio_impl.h b/sources/android/support/src/stdio/stdio_impl.h
new file mode 100644
index 0000000..51ce59c
--- /dev/null
+++ b/sources/android/support/src/stdio/stdio_impl.h
@@ -0,0 +1,63 @@
+// The Musl sources for snprintf(), sscanf() assume they can use a specially
+// crafted FILE object to represent the output/input buffers. However, this
+// doesn't work when using FILE handle from Bionic.
+//
+// This header is used to 'cheat' by redefining FILE and a few other macro
+// redefinitions for functions used in the sources in this directory.
+
+#ifndef STDIO_IMPL_H
+#define STDIO_IMPL_H
+
+#define __HIDDEN__  __attribute__((__visibility__("hidden")))
+
+// A structure that wraps either a real FILE* handle, or an input/output
+// buffer.
+typedef struct {
+  FILE* file;
+  unsigned char* buffer;
+  size_t buffer_size;
+  size_t buffer_pos;
+} FakeFILE;
+
+// Initialize FakeFILE wrapper |file| to use a FILE* handle |f|
+void fake_file_init_file(FakeFILE* file, FILE* f) __HIDDEN__;
+
+// Initialize FakeFILE wrapper |file| to use a |buffer| of |buffer_size| chars.
+void fake_file_init_buffer(FakeFILE* file, char* buffer, size_t buffer_size)
+    __HIDDEN__;
+
+// Initialize FakeFILE wrapper |file| to use a wchar_t |buffer| of
+// |buffer_size| wide-chars.
+void fake_file_init_wbuffer(FakeFILE* file, wchar_t* buffer, size_t buffer_size)
+    __HIDDEN__;
+
+// Replacement for out() in vfprintf.c
+void fake_file_out(FakeFILE* file, const char* s, size_t l) __HIDDEN__;
+
+// Replacement for out() in fvwprintf.c
+void fake_file_outw(FakeFILE* file, const wchar_t* s, size_t l) __HIDDEN__;
+
+// Fake replacement for stdio functions of similar names.
+int fake_feof(FakeFILE* file) __HIDDEN__;
+int fake_ferror(FakeFILE* file) __HIDDEN__;
+int fake_fprintf(FakeFILE* file, const char* fmt, ...) __HIDDEN__;
+void fake_fputc(char ch, FakeFILE* file) __HIDDEN__;
+void fake_fputwc(wchar_t wc, FakeFILE* file) __HIDDEN__;
+
+#ifndef _STDIO_IMPL_NO_REDIRECT_MACROS
+
+// Macro redirection - ugly but necessary to minimize changes to the sources.
+#define FILE FakeFILE
+
+#undef feof
+#define feof fake_feof
+
+#undef ferror
+#define ferror fake_ferror
+#define fprintf fake_fprintf
+#define fputc fake_fputc
+#define fputwc fake_fputwc
+
+#endif  /* _STDIO_IMPL_NO_REDIRECT_MACROS */
+
+#endif  /* STDIO_IMPL_H */
diff --git a/sources/android/support/src/stdio/vfprintf.c b/sources/android/support/src/stdio/vfprintf.c
new file mode 100644
index 0000000..5789acf
--- /dev/null
+++ b/sources/android/support/src/stdio/vfprintf.c
@@ -0,0 +1,780 @@
+/*
+  Copyright (C) 2005-2012 Rich Felker
+
+  Permission is hereby granted, free of charge, to any person obtaining
+  a copy of this software and associated documentation files (the
+  "Software"), to deal in the Software without restriction, including
+  without limitation the rights to use, copy, modify, merge, publish,
+  distribute, sublicense, and/or sell copies of the Software, and to
+  permit persons to whom the Software is furnished to do so, subject to
+  the following conditions:
+
+  The above copyright notice and this permission notice shall be
+  included in all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+  Modified in 2013 for the Android Open Source Project.
+ */
+#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
+#include <string.h>
+#include <stdarg.h>
+#include <wchar.h>
+#include <inttypes.h>
+#include <math.h>
+#include <float.h>
+
+#include "stdio_impl.h"
+
+/* Some useful macros */
+
+#define MAX(a,b) ((a)>(b) ? (a) : (b))
+#define MIN(a,b) ((a)<(b) ? (a) : (b))
+#define CONCAT2(x,y) x ## y
+#define CONCAT(x,y) CONCAT2(x,y)
+
+/* Convenient bit representation for modifier flags, which all fall
+ * within 31 codepoints of the space character. */
+
+#define ALT_FORM   (1U<<'#'-' ')
+#define ZERO_PAD   (1U<<'0'-' ')
+#define LEFT_ADJ   (1U<<'-'-' ')
+#define PAD_POS    (1U<<' '-' ')
+#define MARK_POS   (1U<<'+'-' ')
+#define GROUPED    (1U<<'\''-' ')
+
+#define FLAGMASK (ALT_FORM|ZERO_PAD|LEFT_ADJ|PAD_POS|MARK_POS|GROUPED)
+
+#if UINT_MAX == ULONG_MAX
+#define LONG_IS_INT
+#endif
+
+#if SIZE_MAX != ULONG_MAX || UINTMAX_MAX != ULLONG_MAX
+#define ODD_TYPES
+#endif
+
+/* State machine to accept length modifiers + conversion specifiers.
+ * Result is 0 on failure, or an argument type to pop on success. */
+
+enum {
+	BARE, LPRE, LLPRE, HPRE, HHPRE, BIGLPRE,
+	ZTPRE, JPRE,
+	STOP,
+	PTR, INT, UINT, ULLONG,
+#ifndef LONG_IS_INT
+	LONG, ULONG,
+#else
+#define LONG INT
+#define ULONG UINT
+#endif
+	SHORT, USHORT, CHAR, UCHAR,
+#ifdef ODD_TYPES
+	LLONG, SIZET, IMAX, UMAX, PDIFF, UIPTR,
+#else
+#define LLONG ULLONG
+#define SIZET ULONG
+#define IMAX LLONG
+#define UMAX ULLONG
+#define PDIFF LONG
+#define UIPTR ULONG
+#endif
+	DBL, LDBL,
+	NOARG,
+	MAXSTATE
+};
+
+#define S(x) [(x)-'A']
+
+static const unsigned char states[]['z'-'A'+1] = {
+	{ /* 0: bare types */
+		S('d') = INT, S('i') = INT,
+		S('o') = UINT, S('u') = UINT, S('x') = UINT, S('X') = UINT,
+		S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL,
+		S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL,
+		S('c') = CHAR, S('C') = INT,
+		S('s') = PTR, S('S') = PTR, S('p') = UIPTR, S('n') = PTR,
+		S('m') = NOARG,
+		S('l') = LPRE, S('h') = HPRE, S('L') = BIGLPRE,
+		S('z') = ZTPRE, S('j') = JPRE, S('t') = ZTPRE,
+	}, { /* 1: l-prefixed */
+		S('d') = LONG, S('i') = LONG,
+		S('o') = ULONG, S('u') = ULONG, S('x') = ULONG, S('X') = ULONG,
+		S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL,
+		S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL,
+		S('c') = INT, S('s') = PTR, S('n') = PTR,
+		S('l') = LLPRE,
+	}, { /* 2: ll-prefixed */
+		S('d') = LLONG, S('i') = LLONG,
+		S('o') = ULLONG, S('u') = ULLONG,
+		S('x') = ULLONG, S('X') = ULLONG,
+		S('n') = PTR,
+	}, { /* 3: h-prefixed */
+		S('d') = SHORT, S('i') = SHORT,
+		S('o') = USHORT, S('u') = USHORT,
+		S('x') = USHORT, S('X') = USHORT,
+		S('n') = PTR,
+		S('h') = HHPRE,
+	}, { /* 4: hh-prefixed */
+		S('d') = CHAR, S('i') = CHAR,
+		S('o') = UCHAR, S('u') = UCHAR,
+		S('x') = UCHAR, S('X') = UCHAR,
+		S('n') = PTR,
+	}, { /* 5: L-prefixed */
+		S('e') = LDBL, S('f') = LDBL, S('g') = LDBL, S('a') = LDBL,
+		S('E') = LDBL, S('F') = LDBL, S('G') = LDBL, S('A') = LDBL,
+		S('n') = PTR,
+	}, { /* 6: z- or t-prefixed (assumed to be same size) */
+		S('d') = PDIFF, S('i') = PDIFF,
+		S('o') = SIZET, S('u') = SIZET,
+		S('x') = SIZET, S('X') = SIZET,
+		S('n') = PTR,
+	}, { /* 7: j-prefixed */
+		S('d') = IMAX, S('i') = IMAX,
+		S('o') = UMAX, S('u') = UMAX,
+		S('x') = UMAX, S('X') = UMAX,
+		S('n') = PTR,
+	}
+};
+
+#define OOB(x) ((unsigned)(x)-'A' > 'z'-'A')
+
+union arg
+{
+	uintmax_t i;
+	long double f;
+	void *p;
+};
+
+static void pop_arg(union arg *arg, int type, va_list *ap)
+{
+	/* Give the compiler a hint for optimizing the switch. */
+	if ((unsigned)type > MAXSTATE) return;
+	switch (type) {
+	       case PTR:	arg->p = va_arg(*ap, void *);
+	break; case INT:	arg->i = va_arg(*ap, int);
+	break; case UINT:	arg->i = va_arg(*ap, unsigned int);
+#ifndef LONG_IS_INT
+	break; case LONG:	arg->i = va_arg(*ap, long);
+	break; case ULONG:	arg->i = va_arg(*ap, unsigned long);
+#endif
+	break; case ULLONG:	arg->i = va_arg(*ap, unsigned long long);
+	break; case SHORT:	arg->i = (short)va_arg(*ap, int);
+	break; case USHORT:	arg->i = (unsigned short)va_arg(*ap, int);
+	break; case CHAR:	arg->i = (signed char)va_arg(*ap, int);
+	break; case UCHAR:	arg->i = (unsigned char)va_arg(*ap, int);
+#ifdef ODD_TYPES
+	break; case LLONG:	arg->i = va_arg(*ap, long long);
+	break; case SIZET:	arg->i = va_arg(*ap, size_t);
+	break; case IMAX:	arg->i = va_arg(*ap, intmax_t);
+	break; case UMAX:	arg->i = va_arg(*ap, uintmax_t);
+	break; case PDIFF:	arg->i = va_arg(*ap, ptrdiff_t);
+	break; case UIPTR:	arg->i = (uintptr_t)va_arg(*ap, void *);
+#endif
+	break; case DBL:	arg->f = va_arg(*ap, double);
+	break; case LDBL:	arg->f = va_arg(*ap, long double);
+	}
+}
+
+static void out(FILE *f, const char *s, size_t l)
+{
+#if defined(__ANDROID__)
+        fake_file_out(f, s, l);
+#else
+	__fwritex((void *)s, l, f);
+#endif
+}
+
+static void pad(FILE *f, char c, int w, int l, int fl)
+{
+	char pad[256];
+	if (fl & (LEFT_ADJ | ZERO_PAD) || l >= w) return;
+	l = w - l;
+	memset(pad, c, l>sizeof pad ? sizeof pad : l);
+	for (; l >= sizeof pad; l -= sizeof pad)
+		out(f, pad, sizeof pad);
+	out(f, pad, l);
+}
+
+static const char xdigits[16] = {
+	"0123456789ABCDEF"
+};
+
+static char *fmt_x(uintmax_t x, char *s, int lower)
+{
+	for (; x; x>>=4) *--s = xdigits[(x&15)]|lower;
+	return s;
+}
+
+static char *fmt_o(uintmax_t x, char *s)
+{
+	for (; x; x>>=3) *--s = '0' + (x&7);
+	return s;
+}
+
+static char *fmt_u(uintmax_t x, char *s)
+{
+	unsigned long y;
+	for (   ; x>ULONG_MAX; x/=10) *--s = '0' + x%10;
+	for (y=x;           y; y/=10) *--s = '0' + y%10;
+	return s;
+}
+
+static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
+{
+	uint32_t big[(LDBL_MAX_EXP+LDBL_MANT_DIG)/9+1];
+	uint32_t *a, *d, *r, *z;
+	int e2=0, e, i, j, l;
+	char buf[9+LDBL_MANT_DIG/4], *s;
+	const char *prefix="-0X+0X 0X-0x+0x 0x";
+	int pl;
+	char ebuf0[3*sizeof(int)], *ebuf=&ebuf0[3*sizeof(int)], *estr;
+
+	pl=1;
+	if (signbit(y)) {
+		y=-y;
+	} else if (fl & MARK_POS) {
+		prefix+=3;
+	} else if (fl & PAD_POS) {
+		prefix+=6;
+	} else prefix++, pl=0;
+
+	if (!isfinite(y)) {
+		char *s = (t&32)?"inf":"INF";
+		if (y!=y) s=(t&32)?"nan":"NAN", pl=0;
+		pad(f, ' ', w, 3+pl, fl&~ZERO_PAD);
+		out(f, prefix, pl);
+		out(f, s, 3);
+		pad(f, ' ', w, 3+pl, fl^LEFT_ADJ);
+		return MAX(w, 3+pl);
+	}
+
+	y = frexpl(y, &e2) * 2;
+	if (y) e2--;
+
+	if ((t|32)=='a') {
+		long double round = 8.0;
+		int re;
+
+		if (t&32) prefix += 9;
+		pl += 2;
+
+		if (p<0 || p>=LDBL_MANT_DIG/4-1) re=0;
+		else re=LDBL_MANT_DIG/4-1-p;
+
+		if (re) {
+			while (re--) round*=16;
+			if (*prefix=='-') {
+				y=-y;
+				y-=round;
+				y+=round;
+				y=-y;
+			} else {
+				y+=round;
+				y-=round;
+			}
+		}
+
+		estr=fmt_u(e2<0 ? -e2 : e2, ebuf);
+		if (estr==ebuf) *--estr='0';
+		*--estr = (e2<0 ? '-' : '+');
+		*--estr = t+('p'-'a');
+
+		s=buf;
+		do {
+			int x=y;
+			*s++=xdigits[x]|(t&32);
+			y=16*(y-x);
+			if (s-buf==1 && (y||p>0||(fl&ALT_FORM))) *s++='.';
+		} while (y);
+
+		if (p && s-buf-2 < p)
+			l = (p+2) + (ebuf-estr);
+		else
+			l = (s-buf) + (ebuf-estr);
+
+		pad(f, ' ', w, pl+l, fl);
+		out(f, prefix, pl);
+		pad(f, '0', w, pl+l, fl^ZERO_PAD);
+		out(f, buf, s-buf);
+		pad(f, '0', l-(ebuf-estr)-(s-buf), 0, 0);
+		out(f, estr, ebuf-estr);
+		pad(f, ' ', w, pl+l, fl^LEFT_ADJ);
+		return MAX(w, pl+l);
+	}
+	if (p<0) p=6;
+
+	if (y) y *= 0x1p28, e2-=28;
+
+	if (e2<0) a=r=z=big;
+	else a=r=z=big+sizeof(big)/sizeof(*big) - LDBL_MANT_DIG - 1;
+
+	do {
+		*z = y;
+		y = 1000000000*(y-*z++);
+	} while (y);
+
+	while (e2>0) {
+		uint32_t carry=0;
+		int sh=MIN(29,e2);
+		for (d=z-1; d>=a; d--) {
+			uint64_t x = ((uint64_t)*d<<sh)+carry;
+			*d = x % 1000000000;
+			carry = x / 1000000000;
+		}
+		if (!z[-1] && z>a) z--;
+		if (carry) *--a = carry;
+		e2-=sh;
+	}
+	while (e2<0) {
+		uint32_t carry=0, *b;
+		int sh=MIN(9,-e2);
+		for (d=a; d<z; d++) {
+			uint32_t rm = *d & (1<<sh)-1;
+			*d = (*d>>sh) + carry;
+			carry = (1000000000>>sh) * rm;
+		}
+		if (!*a) a++;
+		if (carry) *z++ = carry;
+		/* Avoid (slow!) computation past requested precision */
+		b = (t|32)=='f' ? r : a;
+		if (z-b > 2+p/9) z = b+2+p/9;
+		e2+=sh;
+	}
+
+	if (a<z) for (i=10, e=9*(r-a); *a>=i; i*=10, e++);
+	else e=0;
+
+	/* Perform rounding: j is precision after the radix (possibly neg) */
+	j = p - ((t|32)!='f')*e - ((t|32)=='g' && p);
+	if (j < 9*(z-r-1)) {
+		uint32_t x;
+		/* We avoid C's broken division of negative numbers */
+		d = r + 1 + ((j+9*LDBL_MAX_EXP)/9 - LDBL_MAX_EXP);
+		j += 9*LDBL_MAX_EXP;
+		j %= 9;
+		for (i=10, j++; j<9; i*=10, j++);
+		x = *d % i;
+		/* Are there any significant digits past j? */
+		if (x || d+1!=z) {
+			long double round = CONCAT(0x1p,LDBL_MANT_DIG);
+			long double small;
+			if (*d/i & 1) round += 2;
+			if (x<i/2) small=0x0.8p0;
+			else if (x==i/2 && d+1==z) small=0x1.0p0;
+			else small=0x1.8p0;
+			if (pl && *prefix=='-') round*=-1, small*=-1;
+			*d -= x;
+			/* Decide whether to round by probing round+small */
+			if (round+small != round) {
+				*d = *d + i;
+				while (*d > 999999999) {
+					*d--=0;
+					(*d)++;
+				}
+				if (d<a) a=d;
+				for (i=10, e=9*(r-a); *a>=i; i*=10, e++);
+			}
+		}
+		if (z>d+1) z=d+1;
+		for (; !z[-1] && z>a; z--);
+	}
+	
+	if ((t|32)=='g') {
+		if (!p) p++;
+		if (p>e && e>=-4) {
+			t--;
+			p-=e+1;
+		} else {
+			t-=2;
+			p--;
+		}
+		if (!(fl&ALT_FORM)) {
+			/* Count trailing zeros in last place */
+			if (z>a && z[-1]) for (i=10, j=0; z[-1]%i==0; i*=10, j++);
+			else j=9;
+			if ((t|32)=='f')
+				p = MIN(p,MAX(0,9*(z-r-1)-j));
+			else
+				p = MIN(p,MAX(0,9*(z-r-1)+e-j));
+		}
+	}
+	l = 1 + p + (p || (fl&ALT_FORM));
+	if ((t|32)=='f') {
+		if (e>0) l+=e;
+	} else {
+		estr=fmt_u(e<0 ? -e : e, ebuf);
+		while(ebuf-estr<2) *--estr='0';
+		*--estr = (e<0 ? '-' : '+');
+		*--estr = t;
+		l += ebuf-estr;
+	}
+
+	pad(f, ' ', w, pl+l, fl);
+	out(f, prefix, pl);
+	pad(f, '0', w, pl+l, fl^ZERO_PAD);
+
+	if ((t|32)=='f') {
+		if (a>r) a=r;
+		for (d=a; d<=r; d++) {
+			char *s = fmt_u(*d, buf+9);
+			if (d!=a) while (s>buf) *--s='0';
+			else if (s==buf+9) *--s='0';
+			out(f, s, buf+9-s);
+		}
+		if (p || (fl&ALT_FORM)) out(f, ".", 1);
+		for (; d<z && p>0; d++, p-=9) {
+			char *s = fmt_u(*d, buf+9);
+			while (s>buf) *--s='0';
+			out(f, s, MIN(9,p));
+		}
+		pad(f, '0', p+9, 9, 0);
+	} else {
+		if (z<=a) z=a+1;
+		for (d=a; d<z && p>=0; d++) {
+			char *s = fmt_u(*d, buf+9);
+			if (s==buf+9) *--s='0';
+			if (d!=a) while (s>buf) *--s='0';
+			else {
+				out(f, s++, 1);
+				if (p>0||(fl&ALT_FORM)) out(f, ".", 1);
+			}
+			out(f, s, MIN(buf+9-s, p));
+			p -= buf+9-s;
+		}
+		pad(f, '0', p+18, 18, 0);
+		out(f, estr, ebuf-estr);
+	}
+
+	pad(f, ' ', w, pl+l, fl^LEFT_ADJ);
+
+	return MAX(w, pl+l);
+}
+
+static int getint(char **s) {
+	int i;
+	for (i=0; isdigit(**s); (*s)++)
+		i = 10*i + (**s-'0');
+	return i;
+}
+
+static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg, int *nl_type)
+{
+	char *a, *z, *s=(char *)fmt;
+	unsigned l10n=0, fl;
+	int w, p;
+	union arg arg;
+	int argpos;
+	unsigned st, ps;
+	int cnt=0, l=0;
+	int i;
+	char buf[sizeof(uintmax_t)*3+3+LDBL_MANT_DIG/4];
+	const char *prefix;
+	int t, pl;
+	wchar_t wc[2], *ws;
+	char mb[4];
+
+	for (;;) {
+		/* Update output count, end loop when fmt is exhausted */
+		if (cnt >= 0) {
+			if (l > INT_MAX - cnt) {
+				errno = EOVERFLOW;
+				cnt = -1;
+			} else cnt += l;
+		}
+		if (!*s) break;
+
+		/* Handle literal text and %% format specifiers */
+		for (a=s; *s && *s!='%'; s++);
+		for (z=s; s[0]=='%' && s[1]=='%'; z++, s+=2);
+		l = z-a;
+		if (f) out(f, a, l);
+		if (l) continue;
+
+		if (isdigit(s[1]) && s[2]=='$') {
+			l10n=1;
+			argpos = s[1]-'0';
+			s+=3;
+		} else {
+			argpos = -1;
+			s++;
+		}
+
+		/* Read modifier flags */
+		for (fl=0; (unsigned)*s-' '<32 && (FLAGMASK&(1U<<*s-' ')); s++)
+			fl |= 1U<<*s-' ';
+
+		/* Read field width */
+		if (*s=='*') {
+			if (isdigit(s[1]) && s[2]=='$') {
+				l10n=1;
+				nl_type[s[1]-'0'] = INT;
+				w = nl_arg[s[1]-'0'].i;
+				s+=3;
+			} else if (!l10n) {
+				w = f ? va_arg(*ap, int) : 0;
+				s++;
+			} else return -1;
+			if (w<0) fl|=LEFT_ADJ, w=-w;
+		} else if ((w=getint(&s))<0) return -1;
+
+		/* Read precision */
+		if (*s=='.' && s[1]=='*') {
+			if (isdigit(s[2]) && s[3]=='$') {
+				nl_type[s[2]-'0'] = INT;
+				p = nl_arg[s[2]-'0'].i;
+				s+=4;
+			} else if (!l10n) {
+				p = f ? va_arg(*ap, int) : 0;
+				s+=2;
+			} else return -1;
+		} else if (*s=='.') {
+			s++;
+			p = getint(&s);
+		} else p = -1;
+
+		/* Format specifier state machine */
+		st=0;
+		do {
+			if (OOB(*s)) return -1;
+			ps=st;
+			st=states[st]S(*s++);
+		} while (st-1<STOP);
+		if (!st) return -1;
+
+		/* Check validity of argument type (nl/normal) */
+		if (st==NOARG) {
+			if (argpos>=0) return -1;
+			else if (!f) continue;
+		} else {
+			if (argpos>=0) nl_type[argpos]=st, arg=nl_arg[argpos];
+			else if (f) pop_arg(&arg, st, ap);
+			else return 0;
+		}
+
+		if (!f) continue;
+
+		z = buf + sizeof(buf);
+		prefix = "-+   0X0x";
+		pl = 0;
+		t = s[-1];
+
+		/* Transform ls,lc -> S,C */
+		if (ps && (t&15)==3) t&=~32;
+
+		/* - and 0 flags are mutually exclusive */
+		if (fl & LEFT_ADJ) fl &= ~ZERO_PAD;
+
+		switch(t) {
+		case 'n':
+#ifndef __ANDROID__  /* Disabled on Android for security reasons. */
+			switch(ps) {
+			case BARE: *(int *)arg.p = cnt; break;
+			case LPRE: *(long *)arg.p = cnt; break;
+			case LLPRE: *(long long *)arg.p = cnt; break;
+			case HPRE: *(unsigned short *)arg.p = cnt; break;
+			case HHPRE: *(unsigned char *)arg.p = cnt; break;
+			case ZTPRE: *(size_t *)arg.p = cnt; break;
+			case JPRE: *(uintmax_t *)arg.p = cnt; break;
+			}
+#endif  /* !__ANDROID__ */
+			continue;
+		case 'p':
+			p = MAX(p, 2*sizeof(void*));
+			t = 'x';
+			fl |= ALT_FORM;
+		case 'x': case 'X':
+			a = fmt_x(arg.i, z, t&32);
+			if (arg.i && (fl & ALT_FORM)) prefix+=(t>>4), pl=2;
+			if (0) {
+		case 'o':
+			a = fmt_o(arg.i, z);
+			if ((fl&ALT_FORM) && arg.i) prefix+=5, pl=1;
+			} if (0) {
+		case 'd': case 'i':
+			pl=1;
+			if (arg.i>INTMAX_MAX) {
+				arg.i=-arg.i;
+			} else if (fl & MARK_POS) {
+				prefix++;
+			} else if (fl & PAD_POS) {
+				prefix+=2;
+			} else pl=0;
+		case 'u':
+			a = fmt_u(arg.i, z);
+			}
+			if (p>=0) fl &= ~ZERO_PAD;
+			if (!arg.i && !p) {
+				a=z;
+				break;
+			}
+			p = MAX(p, z-a + !arg.i);
+			break;
+		case 'c':
+			*(a=z-(p=1))=arg.i;
+			fl &= ~ZERO_PAD;
+			break;
+		case 'm':
+			if (1) a = strerror(errno); else
+		case 's':
+			a = arg.p ? arg.p : "(null)";
+#if defined(__ANDROID__)
+                        /* On Android, memchr() will return NULL for
+                         * out-of-bound requests, e.g. if |p == -1|. */
+                        if (p >= 0) {
+                          z = memchr(a, 0, p);
+                          if (!z) z=a+p;
+                          else p=z-a;
+                        } else {
+                          p=strlen(a);
+                          z=a+p;
+                        }
+#else  /* !__ANDROID__ */
+			if (!z) z=a+p;
+			else p=z-a;
+#endif  /* !__ANDROID__ */
+			fl &= ~ZERO_PAD;
+			break;
+		case 'C':
+			wc[0] = arg.i;
+			wc[1] = 0;
+			arg.p = wc;
+			p = -1;
+		case 'S':
+			ws = arg.p;
+			for (i=l=0; i<0U+p && *ws && (l=wctomb(mb, *ws++))>=0 && l<=0U+p-i; i+=l);
+			if (l<0) return -1;
+			p = i;
+			pad(f, ' ', w, p, fl);
+			ws = arg.p;
+			for (i=0; i<0U+p && *ws && i+(l=wctomb(mb, *ws++))<=p; i+=l)
+				out(f, mb, l);
+			pad(f, ' ', w, p, fl^LEFT_ADJ);
+			l = w>p ? w : p;
+			continue;
+		case 'e': case 'f': case 'g': case 'a':
+		case 'E': case 'F': case 'G': case 'A':
+			l = fmt_fp(f, arg.f, w, p, fl, t);
+			continue;
+		}
+
+		if (p < z-a) p = z-a;
+		if (w < pl+p) w = pl+p;
+
+		pad(f, ' ', w, pl+p, fl);
+		out(f, prefix, pl);
+		pad(f, '0', w, pl+p, fl^ZERO_PAD);
+		pad(f, '0', p, z-a, 0);
+		out(f, a, z-a);
+		pad(f, ' ', w, pl+p, fl^LEFT_ADJ);
+
+		l = w;
+	}
+
+	if (f) return cnt;
+	if (!l10n) return 0;
+
+	for (i=1; i<=NL_ARGMAX && nl_type[i]; i++)
+		pop_arg(nl_arg+i, nl_type[i], ap);
+	for (; i<=NL_ARGMAX && !nl_type[i]; i++);
+	if (i<=NL_ARGMAX) return -1;
+	return 1;
+}
+
+#ifdef __ANDROID__
+#undef FILE  /* no longer needed */
+
+int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap)
+{
+	va_list ap2;
+	int nl_type[NL_ARGMAX+1] = {0};
+	union arg nl_arg[NL_ARGMAX+1];
+	int ret;
+        FakeFILE out[1];
+        fake_file_init_file(out, f);
+
+	va_copy(ap2, ap);
+        ret = printf_core(0, fmt, &ap2, nl_arg, nl_type);
+        va_end(ap2);
+        if (ret < 0)
+          return -1;
+
+        va_copy(ap2, ap);
+	ret = printf_core(out, fmt, &ap2, nl_arg, nl_type);
+	va_end(ap2);
+	return ret;
+}
+
+int vsnprintf(char *restrict s, size_t n, const char *restrict fmt, va_list ap)
+{
+        va_list ap2;
+        int nl_type[NL_ARGMAX+1] = {0};
+        union arg nl_arg[NL_ARGMAX+1];
+        int r;
+        char b;
+        FakeFILE out[1];
+
+        if (n-1 > INT_MAX-1) {
+                if (n) {
+                        errno = EOVERFLOW;
+                        return -1;
+                }
+                s = &b;
+                n = 1;
+        }
+
+        /* Ensure pointers don't wrap if "infinite" n is passed in */
+        if (n > (char *)0+SIZE_MAX-s-1) n = (char *)0+SIZE_MAX-s-1;
+        fake_file_init_buffer(out, s, n);
+
+        va_copy(ap2, ap);
+        r = printf_core(out, fmt, &ap2, nl_arg, nl_type);
+        va_end(ap2);
+
+        if (r < n)
+          s[r] = '\0';
+        else
+          s[n - 1] = '\0';
+
+        return r;
+}
+
+#else  /* !__ANDROID__ */
+int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap)
+{
+        va_list ap2;
+        int nl_type[NL_ARGMAX+1] = {0};
+        union arg nl_arg[NL_ARGMAX+1];
+        unsigned char internal_buf[80], *saved_buf = 0;
+        int ret;
+
+        va_copy(ap2, ap);
+        if (printf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) return -1;
+
+        FLOCK(f);
+        if (!f->buf_size) {
+                saved_buf = f->buf;
+                f->wpos = f->wbase = f->buf = internal_buf;
+                f->buf_size = sizeof internal_buf;
+                f->wend = internal_buf + sizeof internal_buf;
+        }
+        ret = printf_core(f, fmt, &ap2, nl_arg, nl_type);
+        if (saved_buf) {
+                f->write(f, 0, 0);
+                if (!f->wpos) ret = -1;
+                f->buf = saved_buf;
+                f->buf_size = 0;
+                f->wpos = f->wbase = f->wend = 0;
+        }
+        FUNLOCK(f);
+        va_end(ap2);
+        return ret;
+}
+#endif /* !__ANDROID__ */
diff --git a/sources/android/support/src/stdio/vfwprintf.c b/sources/android/support/src/stdio/vfwprintf.c
index 56e5c48..4bf79d6 100644
--- a/sources/android/support/src/stdio/vfwprintf.c
+++ b/sources/android/support/src/stdio/vfwprintf.c
@@ -23,7 +23,6 @@
   Modified in 2013 for the Android Open Source Project.
  */
 
-//#include "stdio_impl.h"
 #include <errno.h>
 #include <ctype.h>
 #include <limits.h>
@@ -32,95 +31,7 @@
 #include <wchar.h>
 #include <inttypes.h>
 
-// A wrapper around either a FILE* or a string buffer, used to output
-// the result of formatted expansion.
-typedef struct {
-  FILE*    file;
-  wchar_t* buffer;
-  size_t   buffer_pos;
-  size_t   buffer_size;
-} Out;
-
-void out_init_file(Out* out, FILE* f) {
-  memset(out, 0, sizeof(*out));
-  out->file = f;
-}
-
-void out_init_buffer(Out* out, wchar_t* buffer, size_t buffer_size) {
-  memset(out, 0, sizeof(*out));
-  out->buffer = buffer;
-  out->buffer_pos = 0;
-  out->buffer_size = buffer_size;
-}
-
-void out_write(Out* out, const wchar_t* text, size_t length) {
-  if (out->file != NULL) {
-    // Write into a file the UTF-8 encoded version.
-    // TODO(digit): Support locale-specific encoding.
-    size_t mb_len = wcstombs(NULL, text, length);
-    char* mb_buffer = malloc(mb_len);
-    wcstombs(mb_buffer, text, length);
-    fwrite(mb_buffer, 1, mb_len, out->file);
-    free(mb_buffer);
-  } else {
-    // Write into a bounded buffer.
-    size_t avail = out->buffer_size - out->buffer_pos;
-    if (length > avail)
-      length = avail;
-    memcpy((char*)(out->buffer + out->buffer_pos),
-           (const char*)text,
-           length * sizeof(wchar_t));
-    out->buffer_pos += length;
-  }
-}
-
-void out_putwc(Out* out, wchar_t wc) {
-  if (out->file)
-    fputwc(wc, out->file);
-  else {
-    if (out->buffer_pos < out->buffer_size)
-      out->buffer[out->buffer_pos++] = wc;
-  }
-}
-
-int out_printf(Out* out, const char* format, ...) {
-  va_list args;
-  va_start(args, format);
-  if (out->file)
-    return vfprintf(out->file, format, args);
-  else {
-    // TODO(digit): Make this faster.
-    // First, generate formatted byte output.
-    int mb_len = vsnprintf(NULL, 0, format, args);
-    char* mb_buffer = malloc(mb_len + 1);
-    vsnprintf(mb_buffer, mb_len + 1, format, args);
-    // Then convert to wchar_t buffer.
-    size_t wide_len = mbstowcs(NULL, mb_buffer, mb_len);
-    wchar_t* wide_buffer = malloc((wide_len + 1) * sizeof(wchar_t));
-    mbstowcs(wide_buffer, mb_buffer, mb_len);
-    // Add to buffer.
-    out_write(out, wide_buffer, wide_len);
-    // finished
-    free(wide_buffer);
-    free(mb_buffer);
-
-    return wide_len;
-  }
-  va_end(args);
-}
-int out_error(Out* out) {
-  if (out->file != NULL)
-    return ferror(out->file);
-
-  return 0;
-}
-
-int out_overflow(Out* out) {
-  if (out->file != NULL)
-    return feof(out->file);
-  else
-    return (out->buffer_pos >= out->buffer_size);
-}
+#include "stdio_impl.h"
 
 /* Convenient bit representation for modifier flags, which all fall
  * within 31 codepoints of the space character. */
@@ -262,6 +173,15 @@
 	}
 }
 
+static void out(FILE *f, const wchar_t *s, size_t l)
+{
+#if defined(__ANDROID__)
+        fake_file_outw(f, s, l);
+#else
+	while (l--) fputwc(*s++, f);
+#endif
+}
+
 static int getint(wchar_t **s) {
 	int i;
 	for (i=0; iswdigit(**s); (*s)++)
@@ -275,7 +195,7 @@
 ['p'-'a']='j'
 };
 
-static int wprintf_core(Out *out, const wchar_t *fmt, va_list *ap, union arg *nl_arg, int *nl_type)
+static int wprintf_core(FILE *f, const wchar_t *fmt, va_list *ap, union arg *nl_arg, int *nl_type)
 {
 	wchar_t *a, *z, *s=(wchar_t *)fmt, *s0;
 	unsigned l10n=0, litpct, fl;
@@ -294,7 +214,7 @@
 		/* Update output count, end loop when fmt is exhausted */
 		if (cnt >= 0) {
 			if (l > INT_MAX - cnt) {
-				if (!out_error(out)) errno = EOVERFLOW;
+				if (!ferror(f)) errno = EOVERFLOW;
 				cnt = -1;
 			} else cnt += l;
 		}
@@ -306,7 +226,7 @@
 		z = s+litpct;
 		s += 2*litpct;
 		l = z-a;
-		if (out) out_write(out, a, l);
+		if (f) out(f, a, l);
 		if (l) continue;
 
 		if (iswdigit(s[1]) && s[2]=='$') {
@@ -330,7 +250,7 @@
 				w = nl_arg[s[1]-'0'].i;
 				s+=3;
 			} else if (!l10n) {
-				w = out ? va_arg(*ap, int) : 0;
+				w = f ? va_arg(*ap, int) : 0;
 				s++;
 			} else return -1;
 			if (w<0) fl|=LEFT_ADJ, w=-w;
@@ -343,7 +263,7 @@
 				p = nl_arg[s[2]-'0'].i;
 				s+=4;
 			} else if (!l10n) {
-				p = out ? va_arg(*ap, int) : 0;
+				p = f ? va_arg(*ap, int) : 0;
 				s+=2;
 			} else return -1;
 		} else if (*s=='.') {
@@ -364,19 +284,20 @@
 		/* Check validity of argument type (nl/normal) */
 		if (st==NOARG) {
 			if (argpos>=0) return -1;
-			else if (!out) continue;
+			else if (!f) continue;
 		} else {
 			if (argpos>=0) nl_type[argpos]=st, arg=nl_arg[argpos];
-			else if (out) pop_arg(&arg, st, ap);
+			else if (f) pop_arg(&arg, st, ap);
 			else return 0;
 		}
 
-		if (!out) continue;
+		if (!f) continue;
 		t = s[-1];
 		if (ps && (t&15)==3) t&=~32;
 
 		switch (t) {
 		case 'n':
+#ifndef __ANDROID__  /* Disabled on Android for security reasons. */
 			switch(ps) {
 			case BARE: *(int *)arg.p = cnt; break;
 			case LPRE: *(long *)arg.p = cnt; break;
@@ -386,13 +307,14 @@
 			case ZTPRE: *(size_t *)arg.p = cnt; break;
 			case JPRE: *(uintmax_t *)arg.p = cnt; break;
 			}
+#endif  /* !__ANDROID__ */
 			continue;
 		case 'c':
-			out_putwc(out, btowc(arg.i));
+			fputwc(btowc(arg.i), f);
 			l = 1;
 			continue;
 		case 'C':
-			out_putwc(out, arg.i);
+			fputwc(arg.i, f);
 			l = 1;
 			continue;
 		case 'S':
@@ -401,9 +323,9 @@
 			if (!z) z=a+p;
 			else p=z-a;
 			if (w<p) w=p;
-			if (!(fl&LEFT_ADJ)) out_printf(out, "%.*s", w-p, "");
-			out_write(out, a, p);
-			if ((fl&LEFT_ADJ)) out_printf(out, "%.*s", w-p, "");
+			if (!(fl&LEFT_ADJ)) fprintf(f, "%.*s", w-p, "");
+			out(f, a, p);
+			if ((fl&LEFT_ADJ)) fprintf(f, "%.*s", w-p, "");
 			l=w;
 			continue;
 		case 's':
@@ -413,14 +335,14 @@
 			if (i<0) return -1;
 			p=l;
 			if (w<p) w=p;
-			if (!(fl&LEFT_ADJ)) out_printf(out, "%.*s", w-p, "");
+			if (!(fl&LEFT_ADJ)) fprintf(f, "%.*s", w-p, "");
 			bs = arg.p;
 			while (l--) {
 				i=mbtowc(&wc, bs, MB_LEN_MAX);
 				bs+=i;
-				out_putwc(out, wc);
+				fputwc(wc, f);
 			}
-			if ((fl&LEFT_ADJ)) out_printf(out, "%.*s", w-p, "");
+			if ((fl&LEFT_ADJ)) fprintf(f, "%.*s", w-p, "");
 			l=w;
 			continue;
 		}
@@ -435,15 +357,15 @@
 
 		switch (t|32) {
 		case 'a': case 'e': case 'f': case 'g':
-			l = out_printf(out, charfmt, w, p, arg.f);
+			l = fprintf(f, charfmt, w, p, arg.f);
 			break;
 		case 'd': case 'i': case 'o': case 'u': case 'x': case 'p':
-			l = out_printf(out, charfmt, w, p, arg.i);
+			l = fprintf(f, charfmt, w, p, arg.i);
 			break;
 		}
 	}
 
-	if (out) return cnt;
+	if (f) return cnt;
 	if (!l10n) return 0;
 
 	for (i=1; i<=NL_ARGMAX && nl_type[i]; i++)
@@ -453,14 +375,16 @@
 	return 1;
 }
 
+#ifdef __ANDROID__
+#undef FILE  /* no longer needed */
 int vfwprintf(FILE *restrict f, const wchar_t *restrict fmt, va_list ap)
 {
 	va_list ap2;
 	int nl_type[NL_ARGMAX] = {0};
 	union arg nl_arg[NL_ARGMAX];
 	int ret;
-        Out out[1];
-        out_init_file(out, f);
+        FakeFILE out[1];
+        fake_file_init_file(out, f);
 	va_copy(ap2, ap);
         // Check for error in format string before writing anything to file.
 	if (wprintf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) {
@@ -478,11 +402,29 @@
   int nl_type[NL_ARGMAX] = {0};
   union arg nl_arg[NL_ARGMAX];
   int ret;
-  Out out[1];
-  out_init_buffer(out, s, l);
+  FakeFILE out[1];
+  fake_file_init_wbuffer(out, s, l);
   va_copy(ap2, ap);
   ret = wprintf_core(out, fmt, &ap2, nl_arg, nl_type);
   va_end(ap2);
-  if (out_overflow(out)) return -1;
+  if (fake_feof(out)) return -1;
   return ret;
 }
+#else  /* !__ANDROID__ */
+int vfwprintf(FILE *restrict f, const wchar_t *restrict fmt, va_list ap)
+{
+	va_list ap2;
+	int nl_type[NL_ARGMAX] = {0};
+	union arg nl_arg[NL_ARGMAX];
+	int ret;
+
+	va_copy(ap2, ap);
+	if (wprintf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) return -1;
+
+	FLOCK(f);
+	ret = wprintf_core(f, fmt, &ap2, nl_arg, nl_type);
+	FUNLOCK(f);
+	va_end(ap2);
+	return ret;
+}
+#endif  /* !__ANDROID__ */
diff --git a/sources/android/support/tests/stdio_unittest.cc b/sources/android/support/tests/stdio_unittest.cc
index 08ace9a..fca503d 100644
--- a/sources/android/support/tests/stdio_unittest.cc
+++ b/sources/android/support/tests/stdio_unittest.cc
@@ -16,6 +16,9 @@
   EXPECT_EQ(L'\0', char_buff[11]);
   EXPECT_EQ(12, snprintf(char_buff, 1, "%s", kString));
   EXPECT_EQ(L'\0', char_buff[0]);
+
+  EXPECT_EQ(20, snprintf(char_buff, char_buff_len, "%a", 3.1415926535));
+  EXPECT_STREQ("0x1.921fb54411744p+1", char_buff);
 }
 
 TEST(stdio,swprintf) {