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/*
* Copyright (C) 2009 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 <stdio.h>
#include <stdlib.h>
#include "PhoneticStringUtils.h"
#include <utils/String8.h>
// We'd like 0 length string last of sorted list. So when input string is NULL
// or 0 length string, we use these instead.
#define CODEPOINT_FOR_NULL_STR 0xFFFD
#define STR_FOR_NULL_STR "\xEF\xBF\xBD"
// We assume that users will not notice strings not sorted properly when the
// first 128 characters are the same.
#define MAX_CODEPOINTS 128
namespace android {
// Get hiragana from halfwidth katakana.
static int GetHiraganaFromHalfwidthKatakana(char32_t codepoint,
char32_t next_codepoint,
bool *next_is_consumed) {
if (codepoint < 0xFF66 || 0xFF9F < codepoint) {
return codepoint;
}
switch (codepoint) {
case 0xFF66: // wo
return 0x3092;
case 0xFF67: // xa
return 0x3041;
case 0xFF68: // xi
return 0x3043;
case 0xFF69: // xu
return 0x3045;
case 0xFF6A: // xe
return 0x3047;
case 0xFF6B: // xo
return 0x3049;
case 0xFF6C: // xya
return 0x3083;
case 0xFF6D: // xyu
return 0x3085;
case 0xFF6E: // xyo
return 0x3087;
case 0xFF6F: // xtsu
return 0x3063;
case 0xFF70: // -
return 0x30FC;
case 0xFF9C: // wa
return 0x308F;
case 0xFF9D: // n
return 0x3093;
break;
default: {
if (0xFF71 <= codepoint && codepoint <= 0xFF75) {
// a, i, u, e, o
if (codepoint == 0xFF73 && next_codepoint == 0xFF9E) {
if (next_is_consumed != NULL) {
*next_is_consumed = true;
}
return 0x3094; // vu
} else {
return 0x3042 + (codepoint - 0xFF71) * 2;
}
} else if (0xFF76 <= codepoint && codepoint <= 0xFF81) {
// ka - chi
if (next_codepoint == 0xFF9E) {
// "dakuten" (voiced mark)
if (next_is_consumed != NULL) {
*next_is_consumed = true;
}
return 0x304B + (codepoint - 0xFF76) * 2 + 1;
} else {
return 0x304B + (codepoint - 0xFF76) * 2;
}
} else if (0xFF82 <= codepoint && codepoint <= 0xFF84) {
// tsu, te, to (skip xtsu)
if (next_codepoint == 0xFF9E) {
// "dakuten" (voiced mark)
if (next_is_consumed != NULL) {
*next_is_consumed = true;
}
return 0x3064 + (codepoint - 0xFF82) * 2 + 1;
} else {
return 0x3064 + (codepoint - 0xFF82) * 2;
}
} else if (0xFF85 <= codepoint && codepoint <= 0xFF89) {
// na, ni, nu, ne, no
return 0x306A + (codepoint - 0xFF85);
} else if (0xFF8A <= codepoint && codepoint <= 0xFF8E) {
// ha, hi, hu, he, ho
if (next_codepoint == 0xFF9E) {
// "dakuten" (voiced mark)
if (next_is_consumed != NULL) {
*next_is_consumed = true;
}
return 0x306F + (codepoint - 0xFF8A) * 3 + 1;
} else if (next_codepoint == 0xFF9F) {
// "han-dakuten" (half voiced mark)
if (next_is_consumed != NULL) {
*next_is_consumed = true;
}
return 0x306F + (codepoint - 0xFF8A) * 3 + 2;
} else {
return 0x306F + (codepoint - 0xFF8A) * 3;
}
} else if (0xFF8F <= codepoint && codepoint <= 0xFF93) {
// ma, mi, mu, me, mo
return 0x307E + (codepoint - 0xFF8F);
} else if (0xFF94 <= codepoint && codepoint <= 0xFF96) {
// ya, yu, yo
return 0x3084 + (codepoint - 0xFF94) * 2;
} else if (0xFF97 <= codepoint && codepoint <= 0xFF9B) {
// ra, ri, ru, re, ro
return 0x3089 + (codepoint - 0xFF97);
}
// Note: 0xFF9C, 0xFF9D are handled above
} // end of default
}
return codepoint;
}
// Assuming input is hiragana, convert the hiragana to "normalized" hiragana.
static int GetNormalizedHiragana(int codepoint) {
if (codepoint < 0x3040 || 0x309F < codepoint) {
return codepoint;
}
// TODO: should care (semi-)voiced mark (0x3099, 0x309A).
// Trivial kana conversions.
// e.g. xa => a
switch (codepoint) {
case 0x3041:
case 0x3043:
case 0x3045:
case 0x3047:
case 0x3049:
case 0x308E: // xwa
return codepoint + 1;
case 0x3095: // xka
return 0x304B;
case 0x3096: // xku
return 0x304F;
default:
return codepoint;
}
}
static int GetNormalizedKana(char32_t codepoint,
char32_t next_codepoint,
bool *next_is_consumed) {
// First, convert fullwidth katakana and halfwidth katakana to hiragana.
if (0x30A1 <= codepoint && codepoint <= 0x30F6) {
// Make fullwidth katakana same as hiragana.
// 96 == 0x30A1 - 0x3041c
codepoint = codepoint - 96;
} else {
codepoint = GetHiraganaFromHalfwidthKatakana(
codepoint, next_codepoint, next_is_consumed);
}
// Normalize Hiragana.
return GetNormalizedHiragana(codepoint);
}
int GetNormalizedCodePoint(char32_t codepoint,
char32_t next_codepoint,
bool *next_is_consumed) {
if (next_is_consumed != NULL) {
*next_is_consumed = false;
}
if (codepoint <= 0x0020 || codepoint == 0x3000) {
// Whitespaces. Keep it as is.
return codepoint;
} else if ((0x0021 <= codepoint && codepoint <= 0x007E) ||
(0xFF01 <= codepoint && codepoint <= 0xFF5E)) {
// Ascii and fullwidth ascii. Keep it as is
return codepoint;
} else if (codepoint == 0x02DC || codepoint == 0x223C) {
// tilde
return 0xFF5E;
} else if (codepoint <= 0x3040 ||
(0x3100 <= codepoint && codepoint < 0xFF00) ||
codepoint == CODEPOINT_FOR_NULL_STR) {
// Keep it as is.
return codepoint;
}
// Below is Kana-related handling.
return GetNormalizedKana(codepoint, next_codepoint, next_is_consumed);
}
static bool GetExpectedString(
const char *src, char **dst, size_t *dst_len,
int (*get_codepoint_function)(char32_t, char32_t, bool*)) {
if (dst == NULL || dst_len == NULL) {
return false;
}
if (src == NULL || *src == '\0') {
src = STR_FOR_NULL_STR;
}
char32_t codepoints[MAX_CODEPOINTS]; // if array size is changed the for loop needs to be changed
size_t src_len = utf8_length(src);
if (src_len == 0) {
return false;
}
bool next_is_consumed;
size_t j = 0;
for (size_t i = 0; i < src_len && j < MAX_CODEPOINTS;) {
int32_t ret = utf32_at(src, src_len, i, &i);
if (ret < 0) {
// failed to parse UTF-8
return false;
}
ret = get_codepoint_function(
static_cast<char32_t>(ret),
i + 1 < src_len ? src[i + 1] : 0,
&next_is_consumed);
if (ret > 0) {
codepoints[j] = static_cast<char32_t>(ret);
j++;
}
if (next_is_consumed) {
i++;
}
}
size_t length = j;
if (length == 0) {
// If all of codepoints are invalid, we place the string at the end of
// the list.
codepoints[0] = 0x10000 + CODEPOINT_FOR_NULL_STR;
length = 1;
}
size_t new_len = utf8_length_from_utf32(codepoints, length);
*dst = static_cast<char *>(malloc(new_len + 1));
if (*dst == NULL) {
return false;
}
if (utf32_to_utf8(codepoints, length, *dst, new_len + 1) != new_len) {
free(*dst);
*dst = NULL;
return false;
}
*dst_len = new_len;
return true;
}
bool GetNormalizedString(const char *src, char **dst, size_t *len) {
return GetExpectedString(src, dst, len, GetNormalizedCodePoint);
}
} // namespace android