1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #define LOG_TAG "Minikin"
18
19 #include "FontLanguageListCache.h"
20
21 #include <unicode/uloc.h>
22 #include <unordered_set>
23
24 #include <log/log.h>
25
26 #include "FontLanguage.h"
27 #include "MinikinInternal.h"
28
29 namespace minikin {
30
31 const uint32_t FontLanguageListCache::kEmptyListId;
32
33 // Returns the text length of output.
toLanguageTag(char * output,size_t outSize,const std::string & locale)34 static size_t toLanguageTag(char* output,
35 size_t outSize,
36 const std::string& locale) {
37 output[0] = '\0';
38 if (locale.empty()) {
39 return 0;
40 }
41
42 size_t outLength = 0;
43 UErrorCode uErr = U_ZERO_ERROR;
44 outLength = uloc_canonicalize(locale.c_str(), output, outSize, &uErr);
45 if (U_FAILURE(uErr)) {
46 // unable to build a proper language identifier
47 ALOGD("uloc_canonicalize(\"%s\") failed: %s", locale.c_str(),
48 u_errorName(uErr));
49 output[0] = '\0';
50 return 0;
51 }
52
53 // Preserve "und" and "und-****" since uloc_addLikelySubtags changes "und" to
54 // "en-Latn-US".
55 if (strncmp(output, "und", 3) == 0 &&
56 (outLength == 3 || (outLength == 8 && output[3] == '_'))) {
57 return outLength;
58 }
59
60 char likelyChars[ULOC_FULLNAME_CAPACITY];
61 uErr = U_ZERO_ERROR;
62 uloc_addLikelySubtags(output, likelyChars, ULOC_FULLNAME_CAPACITY, &uErr);
63 if (U_FAILURE(uErr)) {
64 // unable to build a proper language identifier
65 ALOGD("uloc_addLikelySubtags(\"%s\") failed: %s", output,
66 u_errorName(uErr));
67 output[0] = '\0';
68 return 0;
69 }
70
71 uErr = U_ZERO_ERROR;
72 outLength = uloc_toLanguageTag(likelyChars, output, outSize, FALSE, &uErr);
73 if (U_FAILURE(uErr)) {
74 // unable to build a proper language identifier
75 ALOGD("uloc_toLanguageTag(\"%s\") failed: %s", likelyChars,
76 u_errorName(uErr));
77 output[0] = '\0';
78 return 0;
79 }
80 #ifdef VERBOSE_DEBUG
81 ALOGD("ICU normalized '%s' to '%s'", locale.c_str(), output);
82 #endif
83 return outLength;
84 }
85
parseLanguageList(const std::string & input)86 static std::vector<FontLanguage> parseLanguageList(const std::string& input) {
87 std::vector<FontLanguage> result;
88 size_t currentIdx = 0;
89 size_t commaLoc = 0;
90 char langTag[ULOC_FULLNAME_CAPACITY];
91 std::unordered_set<uint64_t> seen;
92 std::string locale(input.size(), 0);
93
94 while ((commaLoc = input.find_first_of(',', currentIdx)) !=
95 std::string::npos) {
96 locale.assign(input, currentIdx, commaLoc - currentIdx);
97 currentIdx = commaLoc + 1;
98 size_t length = toLanguageTag(langTag, ULOC_FULLNAME_CAPACITY, locale);
99 FontLanguage lang(langTag, length);
100 uint64_t identifier = lang.getIdentifier();
101 if (!lang.isUnsupported() && seen.count(identifier) == 0) {
102 result.push_back(lang);
103 if (result.size() == FONT_LANGUAGES_LIMIT) {
104 break;
105 }
106 seen.insert(identifier);
107 }
108 }
109 if (result.size() < FONT_LANGUAGES_LIMIT) {
110 locale.assign(input, currentIdx, input.size() - currentIdx);
111 size_t length = toLanguageTag(langTag, ULOC_FULLNAME_CAPACITY, locale);
112 FontLanguage lang(langTag, length);
113 uint64_t identifier = lang.getIdentifier();
114 if (!lang.isUnsupported() && seen.count(identifier) == 0) {
115 result.push_back(lang);
116 }
117 }
118 return result;
119 }
120
121 // static
getId(const std::string & languages)122 uint32_t FontLanguageListCache::getId(const std::string& languages) {
123 FontLanguageListCache* inst = FontLanguageListCache::getInstance();
124 std::unordered_map<std::string, uint32_t>::const_iterator it =
125 inst->mLanguageListLookupTable.find(languages);
126 if (it != inst->mLanguageListLookupTable.end()) {
127 return it->second;
128 }
129
130 // Given language list is not in cache. Insert it and return newly assigned
131 // ID.
132 const uint32_t nextId = inst->mLanguageLists.size();
133 FontLanguages fontLanguages(parseLanguageList(languages));
134 if (fontLanguages.empty()) {
135 return kEmptyListId;
136 }
137 inst->mLanguageLists.push_back(std::move(fontLanguages));
138 inst->mLanguageListLookupTable.insert(std::make_pair(languages, nextId));
139 return nextId;
140 }
141
142 // static
getById(uint32_t id)143 const FontLanguages& FontLanguageListCache::getById(uint32_t id) {
144 FontLanguageListCache* inst = FontLanguageListCache::getInstance();
145 LOG_ALWAYS_FATAL_IF(id >= inst->mLanguageLists.size(),
146 "Lookup by unknown language list ID.");
147 return inst->mLanguageLists[id];
148 }
149
150 // static
getInstance()151 FontLanguageListCache* FontLanguageListCache::getInstance() {
152 assertMinikinLocked();
153 static FontLanguageListCache* instance = nullptr;
154 if (instance == nullptr) {
155 instance = new FontLanguageListCache();
156
157 // Insert an empty language list for mapping default language list to
158 // kEmptyListId. The default language list has only one FontLanguage and it
159 // is the unsupported language.
160 instance->mLanguageLists.push_back(FontLanguages());
161 instance->mLanguageListLookupTable.insert(std::make_pair("", kEmptyListId));
162 }
163 return instance;
164 }
165
166 } // namespace minikin
167