1 files changed, 65 insertions, 0 deletions
diff --git a/native/jni/src/char_utils.h b/native/jni/src/char_utils.h
new file mode 100644
index 000000000..607dc5195
--- /dev/null
+++ b/native/jni/src/char_utils.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+#ifndef LATINIME_CHAR_UTILS_H
+#define LATINIME_CHAR_UTILS_H
+
+namespace latinime {
+
+inline static int isAsciiUpper(unsigned short c) {
+    return c >= 'A' && c <= 'Z';
+}
+
+inline static unsigned short toAsciiLower(unsigned short c) {
+    return c - 'A' + 'a';
+}
+
+inline static int isAscii(unsigned short c) {
+    return c <= 127;
+}
+
+unsigned short latin_tolower(unsigned short c);
+
+/**
+ * Table mapping most combined Latin, Greek, and Cyrillic characters
+ * to their base characters.  If c is in range, BASE_CHARS[c] == c
+ * if c is not a combined character, or the base character if it
+ * is combined.
+ */
+
+static const int BASE_CHARS_SIZE = 0x0500;
+extern const unsigned short BASE_CHARS[BASE_CHARS_SIZE];
+
+inline static unsigned short toBaseChar(unsigned short c) {
+    if (c < BASE_CHARS_SIZE) {
+        return BASE_CHARS[c];
+    }
+    return c;
+}
+
+inline static unsigned short toBaseLowerCase(unsigned short c) {
+    c = toBaseChar(c);
+    if (isAsciiUpper(c)) {
+        return toAsciiLower(c);
+    } else if (isAscii(c)) {
+        return c;
+    }
+    return latin_tolower(c);
+}
+
+} // namespace latinime
+
+#endif // LATINIME_CHAR_UTILS_H