Implement wcwidth(3) in terms of icu4c.

Based on com.google.i18n.CharWidth by the icu-team folks.

Bug: N/A
Test: ran tests
Change-Id: Ia9d818ec4ae60f2f3978533195330d00699397c5
diff --git a/libc/bionic/icu_wrappers.cpp b/libc/bionic/icu_wrappers.cpp
new file mode 100644
index 0000000..d9f2745
--- /dev/null
+++ b/libc/bionic/icu_wrappers.cpp
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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 "private/icu.h"
+
+int8_t __icu_charType(wint_t wc) {
+  typedef int8_t (*u_charType_t)(UChar32);
+  static auto u_charType = reinterpret_cast<u_charType_t>(__find_icu_symbol("u_charType"));
+  return u_charType ? u_charType(wc) : -1;
+}
+
+int32_t __icu_getIntPropertyValue(wint_t wc, UProperty property) {
+  typedef int32_t (*u_getIntPropertyValue_t)(UChar32, UProperty);
+  static auto u_getIntPropertyValue =
+      reinterpret_cast<u_getIntPropertyValue_t>(__find_icu_symbol("u_getIntPropertyValue"));
+  return u_getIntPropertyValue ? u_getIntPropertyValue(wc, property) : 0;
+}
+
+bool __icu_hasBinaryProperty(wint_t wc, UProperty property, int (*fallback)(int)) {
+  typedef UBool (*u_hasBinaryProperty_t)(UChar32, UProperty);
+  static auto u_hasBinaryProperty =
+      reinterpret_cast<u_hasBinaryProperty_t>(__find_icu_symbol("u_hasBinaryProperty"));
+  return u_hasBinaryProperty ? u_hasBinaryProperty(wc, property) : fallback(wc);
+}