diff --git a/libc/Android.mk b/libc/Android.mk
index fd14232..b84c1e1 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -81,7 +81,6 @@
     stdio/sprintf.c \
     stdio/vfprintf.c \
     stdlib/atexit.c \
-    stdlib/ctype_.c \
     stdlib/getenv.c \
     stdlib/putenv.c \
     stdlib/setenv.c \
@@ -338,10 +337,12 @@
 
 libc_upstream_openbsd_src_files := \
     upstream-openbsd/lib/libc/gen/alarm.c \
+    upstream-openbsd/lib/libc/gen/ctype_.c \
     upstream-openbsd/lib/libc/gen/exec.c \
     upstream-openbsd/lib/libc/gen/fnmatch.c \
     upstream-openbsd/lib/libc/gen/ftok.c \
     upstream-openbsd/lib/libc/gen/getprogname.c \
+    upstream-openbsd/lib/libc/gen/isctype.c \
     upstream-openbsd/lib/libc/gen/setprogname.c \
     upstream-openbsd/lib/libc/gen/time.c \
     upstream-openbsd/lib/libc/gen/tolower_.c \
diff --git a/libc/stdlib/ctype_.c b/libc/stdlib/ctype_.c
deleted file mode 100644
index c4f294d..0000000
--- a/libc/stdlib/ctype_.c
+++ /dev/null
@@ -1,159 +0,0 @@
-/*	$OpenBSD: ctype_.c,v 1.9 2005/08/08 08:05:33 espie Exp $ */
-/*
- * Copyright (c) 1989 The Regents of the University of California.
- * All rights reserved.
- * (c) UNIX System Laboratories, Inc.
- * All or some portions of this file are derived from material licensed
- * to the University of California by American Telephone and Telegraph
- * Co. or Unix System Laboratories, Inc. and are reproduced herein with
- * the permission of UNIX System Laboratories, Inc.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <ctype.h>
-#include "ctype_private.h"
-
-#define _U _CTYPE_U
-#define _L _CTYPE_L
-#define _D _CTYPE_D
-#define _S _CTYPE_S
-#define _P _CTYPE_P
-#define _C _CTYPE_C
-#define _X _CTYPE_X
-#define _B _CTYPE_B
-
-const char _C_ctype_[1 + CTYPE_NUM_CHARS] = {
-	0,
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
-	_C,	_C|_S,	_C|_S,	_C|_S,	_C|_S,	_C|_S,	_C,	_C,
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
-   _S|(char)_B,	_P,	_P,	_P,	_P,	_P,	_P,	_P,
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P,
-	_D,	_D,	_D,	_D,	_D,	_D,	_D,	_D,
-	_D,	_D,	_P,	_P,	_P,	_P,	_P,	_P,
-	_P,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U,
-	_U,	_U,	_U,	_U,	_U,	_U,	_U,	_U,
-	_U,	_U,	_U,	_U,	_U,	_U,	_U,	_U,
-	_U,	_U,	_U,	_P,	_P,	_P,	_P,	_P,
-	_P,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L,
-	_L,	_L,	_L,	_L,	_L,	_L,	_L,	_L,
-	_L,	_L,	_L,	_L,	_L,	_L,	_L,	_L,
-	/* determine printability based on the IS0 8859 8-bit standard */
-	_L,	_L,	_L,	_P,	_P,	_P,	_P,	_C,
-
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C, /* 80 */
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C, /* 88 */
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C, /* 90 */
-	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C, /* 98 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* A0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* A8 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* B0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* B8 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* C0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* C8 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* D0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* D8 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* E0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* E8 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P, /* F0 */
-	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P  /* F8 */
-};
-
-const char *_ctype_ = _C_ctype_;
-
-int isalnum(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_U|_L|_D)));
-}
-
-int isalpha(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_U|_L)));
-}
-
-int iscntrl(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _C));
-}
-
-int isdigit(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _D));
-}
-
-int isgraph(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_P|_U|_L|_D)));
-}
-
-int islower(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _L));
-}
-
-int isprint(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_P|_U|_L|_D|_B)));
-}
-
-int ispunct(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _P));
-}
-
-int isspace(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _S));
-}
-
-int isupper(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _U));
-}
-
-int isxdigit(int c)
-{
-	return (c == -1 ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_D|_X)));
-}
-
-int isblank(int c)
-{
-	return (c == ' ' || c == '\t');
-}
-
-int isascii(int c)
-{
-	return ((unsigned int)c <= 0177);
-}
-
-int toascii(int c)
-{
-	return (c & 0177);
-}
-
-__strong_alias(_toupper, toupper);
-__strong_alias(_tolower, tolower);
diff --git a/libc/upstream-openbsd/lib/libc/gen/ctype_.c b/libc/upstream-openbsd/lib/libc/gen/ctype_.c
new file mode 100644
index 0000000..89c8257
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/gen/ctype_.c
@@ -0,0 +1,76 @@
+/*	$OpenBSD: ctype_.c,v 1.10 2011/09/22 09:06:10 stsp Exp $ */
+/*
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <ctype.h>
+#include "ctype_private.h"
+
+const char _C_ctype_[1 + CTYPE_NUM_CHARS] = {
+	0,
+	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
+	_C,	_C|_S,	_C|_S,	_C|_S,	_C|_S,	_C|_S,	_C,	_C,
+	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
+	_C,	_C,	_C,	_C,	_C,	_C,	_C,	_C,
+   _S|(char)_B,	_P,	_P,	_P,	_P,	_P,	_P,	_P,
+	_P,	_P,	_P,	_P,	_P,	_P,	_P,	_P,
+	_N,	_N,	_N,	_N,	_N,	_N,	_N,	_N,
+	_N,	_N,	_P,	_P,	_P,	_P,	_P,	_P,
+	_P,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U|_X,	_U,
+	_U,	_U,	_U,	_U,	_U,	_U,	_U,	_U,
+	_U,	_U,	_U,	_U,	_U,	_U,	_U,	_U,
+	_U,	_U,	_U,	_P,	_P,	_P,	_P,	_P,
+	_P,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L|_X,	_L,
+	_L,	_L,	_L,	_L,	_L,	_L,	_L,	_L,
+	_L,	_L,	_L,	_L,	_L,	_L,	_L,	_L,
+	_L,	_L,	_L,	_P,	_P,	_P,	_P,	_C,
+
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* 80 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* 88 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* 90 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* 98 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* A0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* A8 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* B0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* B8 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* C0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* C8 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* D0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* D8 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* E0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* E8 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0, /* F0 */
+	 0,	 0,	 0,	 0,	 0,	 0,	 0,	 0  /* F8 */
+};
+
+const char *_ctype_ = _C_ctype_;
diff --git a/libc/upstream-openbsd/lib/libc/gen/isctype.c b/libc/upstream-openbsd/lib/libc/gen/isctype.c
new file mode 100644
index 0000000..970b5e2
--- /dev/null
+++ b/libc/upstream-openbsd/lib/libc/gen/isctype.c
@@ -0,0 +1,150 @@
+/*	$OpenBSD: isctype.c,v 1.11 2005/08/08 08:05:34 espie Exp $ */
+/*
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#define _ANSI_LIBRARY
+#include <ctype.h>
+#include <stdio.h>
+
+#undef isalnum
+int
+isalnum(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_U|_L|_N)));
+}
+
+#undef isalpha
+int
+isalpha(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_U|_L)));
+}
+
+#undef isblank
+int
+isblank(int c)
+{
+	return (c == ' ' || c == '\t');
+}
+
+#undef iscntrl
+int
+iscntrl(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _C));
+}
+
+#undef isdigit
+int
+isdigit(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _N));
+}
+
+#undef isgraph
+int
+isgraph(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_P|_U|_L|_N)));
+}
+
+#undef islower
+int
+islower(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _L));
+}
+
+#undef isprint
+int
+isprint(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_P|_U|_L|_N|_B)));
+}
+
+#undef ispunct
+int
+ispunct(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _P));
+}
+
+#undef isspace
+int
+isspace(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _S));
+}
+
+#undef isupper
+int
+isupper(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & _U));
+}
+
+#undef isxdigit
+int
+isxdigit(int c)
+{
+	return (c == EOF ? 0 : ((_ctype_ + 1)[(unsigned char)c] & (_N|_X)));
+}
+
+#undef isascii
+int
+isascii(int c)
+{
+	return ((unsigned int)c <= 0177);
+}
+
+#undef toascii
+int
+toascii(int c)
+{
+	return (c & 0177);
+}
+
+#undef _toupper
+int
+_toupper(int c)
+{
+	return (c - 'a' + 'A');
+}
+
+#undef _tolower
+int
+_tolower(int c)
+{
+	return (c - 'A' + 'a');
+}
diff --git a/libc/stdlib/ctype_private.h b/libc/upstream-openbsd/lib/libc/include/ctype_private.h
similarity index 100%
rename from libc/stdlib/ctype_private.h
rename to libc/upstream-openbsd/lib/libc/include/ctype_private.h
diff --git a/libc/upstream-openbsd/openbsd-compat.h b/libc/upstream-openbsd/openbsd-compat.h
index 2c3fe56..b55f390 100644
--- a/libc/upstream-openbsd/openbsd-compat.h
+++ b/libc/upstream-openbsd/openbsd-compat.h
@@ -20,4 +20,16 @@
 #define _GNU_SOURCE
 #define __USE_BSD
 
+/* OpenBSD's <ctype.h> uses these names, which conflicted with stlport.
+ * Additionally, we changed the numeric/digit type from N to D for libcxx.
+ */
+#define _U _CTYPE_U
+#define _L _CTYPE_L
+#define _N _CTYPE_D
+#define _S _CTYPE_S
+#define _P _CTYPE_P
+#define _C _CTYPE_C
+#define _X _CTYPE_X
+#define _B _CTYPE_B
+
 #endif
diff --git a/tests/Android.mk b/tests/Android.mk
index b32d8d4..723d7cf 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -40,6 +40,7 @@
 
 libBionicStandardTests_src_files := \
     buffer_tests.cpp \
+    ctype_test.cpp \
     dirent_test.cpp \
     eventfd_test.cpp \
     fcntl_test.cpp \
diff --git a/tests/ctype_test.cpp b/tests/ctype_test.cpp
new file mode 100644
index 0000000..7b27d64
--- /dev/null
+++ b/tests/ctype_test.cpp
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gtest/gtest.h>
+
+#include <ctype.h>
+
+TEST(ctype, isalnum) {
+  EXPECT_TRUE(isalnum('1'));
+  EXPECT_TRUE(isalnum('a'));
+  EXPECT_TRUE(isalnum('A'));
+  EXPECT_FALSE(isalnum('!'));
+  EXPECT_FALSE(isalnum(' '));
+}
+
+TEST(ctype, isalpha) {
+  EXPECT_FALSE(isalpha('1'));
+  EXPECT_TRUE(isalpha('a'));
+  EXPECT_TRUE(isalpha('A'));
+  EXPECT_FALSE(isalpha('!'));
+  EXPECT_FALSE(isalpha(' '));
+}
+
+TEST(ctype, isascii) {
+  EXPECT_TRUE(isascii('\x7f'));
+  EXPECT_FALSE(isascii('\x80'));
+}
+
+TEST(ctype, isblank) {
+  EXPECT_FALSE(isblank('1'));
+  EXPECT_TRUE(isblank(' '));
+  EXPECT_TRUE(isblank('\t'));
+}
+
+TEST(ctype, iscntrl) {
+  EXPECT_FALSE(iscntrl('1'));
+  EXPECT_TRUE(iscntrl('\b'));
+}
+
+TEST(ctype, isdigit) {
+  EXPECT_TRUE(isdigit('1'));
+  EXPECT_FALSE(isdigit('a'));
+  EXPECT_FALSE(isdigit('x'));
+}
+
+TEST(ctype, isgraph) {
+  EXPECT_TRUE(isgraph('a'));
+  EXPECT_TRUE(isgraph('A'));
+  EXPECT_TRUE(isgraph('1'));
+  EXPECT_TRUE(isgraph('!'));
+  EXPECT_FALSE(isgraph(' '));
+}
+
+TEST(ctype, islower) {
+  EXPECT_TRUE(islower('a'));
+  EXPECT_FALSE(islower('A'));
+  EXPECT_FALSE(islower('!'));
+}
+
+TEST(ctype, isprint) {
+  EXPECT_TRUE(isprint('a'));
+  EXPECT_TRUE(isprint(' '));
+  EXPECT_FALSE(isprint('\b'));
+}
+
+TEST(ctype, ispunct) {
+  EXPECT_TRUE(ispunct('!'));
+  EXPECT_FALSE(ispunct('a'));
+  EXPECT_FALSE(ispunct(' '));
+  EXPECT_FALSE(ispunct('\b'));
+}
+
+TEST(ctype, isspace) {
+  EXPECT_TRUE(isspace(' '));
+  EXPECT_TRUE(isspace('\f'));
+  EXPECT_TRUE(isspace('\n'));
+  EXPECT_TRUE(isspace('\r'));
+  EXPECT_TRUE(isspace('\t'));
+  EXPECT_TRUE(isspace('\v'));
+  EXPECT_FALSE(isspace('a'));
+  EXPECT_FALSE(isspace('!'));
+}
+
+TEST(ctype, isupper) {
+  EXPECT_TRUE(isupper('A'));
+  EXPECT_FALSE(isupper('a'));
+  EXPECT_FALSE(isupper('!'));
+}
+
+TEST(ctype, isxdigit) {
+  EXPECT_TRUE(isxdigit('0'));
+  EXPECT_FALSE(isxdigit('x'));
+  EXPECT_TRUE(isxdigit('1'));
+  EXPECT_TRUE(isxdigit('a'));
+  EXPECT_TRUE(isxdigit('A'));
+  EXPECT_FALSE(isxdigit('g'));
+  EXPECT_FALSE(isxdigit(' '));
+}
+
+TEST(ctype, toascii) {
+  EXPECT_EQ('a', toascii('a'));
+  EXPECT_EQ('a', toascii(0x80 | 'a'));
+}
+
+TEST(ctype, tolower) {
+  EXPECT_EQ('!', tolower('!'));
+  EXPECT_EQ('a', tolower('a'));
+  EXPECT_EQ('a', tolower('A'));
+}
+
+TEST(ctype, _tolower) {
+  // _tolower may mangle characters for which isupper is false.
+  EXPECT_EQ('a', _tolower('A'));
+}
+
+TEST(ctype, toupper) {
+  EXPECT_EQ('!', toupper('!'));
+  EXPECT_EQ('A', toupper('a'));
+  EXPECT_EQ('A', toupper('A'));
+}
+
+TEST(ctype, _toupper) {
+  // _toupper may mangle characters for which islower is false.
+  EXPECT_EQ('A', _toupper('a'));
+}