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 <unicode/umachine.h>
23 #include <unordered_set>
24
25 #include <log/log.h>
26
27 #include "FontLanguage.h"
28 #include "MinikinInternal.h"
29
30 namespace minikin {
31
32 const uint32_t FontLanguageListCache::kEmptyListId;
33
34 // Returns the text length of output.
toLanguageTag(char * output,size_t outSize,const std::string & locale)35 static size_t toLanguageTag(char* output,
36 size_t outSize,
37 const std::string& locale) {
38 output[0] = '\0';
39 if (locale.empty()) {
40 return 0;
41 }
42
43 size_t outLength = 0;
44 UErrorCode uErr = U_ZERO_ERROR;
45 outLength = uloc_canonicalize(locale.c_str(), output, outSize, &uErr);
46 if (U_FAILURE(uErr)) {
47 // unable to build a proper language identifier
48 ALOGD("uloc_canonicalize(\"%s\") failed: %s", locale.c_str(),
49 u_errorName(uErr));
50 output[0] = '\0';
51 return 0;
52 }
53
54 // Preserve "und" and "und-****" since uloc_addLikelySubtags changes "und" to
55 // "en-Latn-US".
56 if (strncmp(output, "und", 3) == 0 &&
57 (outLength == 3 || (outLength == 8 && output[3] == '_'))) {
58 return outLength;
59 }
60
61 char likelyChars[ULOC_FULLNAME_CAPACITY];
62 uErr = U_ZERO_ERROR;
63 uloc_addLikelySubtags(output, likelyChars, ULOC_FULLNAME_CAPACITY, &uErr);
64 if (U_FAILURE(uErr)) {
65 // unable to build a proper language identifier
66 ALOGD("uloc_addLikelySubtags(\"%s\") failed: %s", output,
67 u_errorName(uErr));
68 output[0] = '\0';
69 return 0;
70 }
71
72 uErr = U_ZERO_ERROR;
73 outLength =
74 uloc_toLanguageTag(likelyChars, output, outSize, /*false*/ 0, &uErr);
75 if (U_FAILURE(uErr)) {
76 // unable to build a proper language identifier
77 ALOGD("uloc_toLanguageTag(\"%s\") failed: %s", likelyChars,
78 u_errorName(uErr));
79 output[0] = '\0';
80 return 0;
81 }
82 #ifdef VERBOSE_DEBUG
83 ALOGD("ICU normalized '%s' to '%s'", locale.c_str(), output);
84 #endif
85 return outLength;
86 }
87
parseLanguageList(const std::string & input)88 static std::vector<FontLanguage> parseLanguageList(const std::string& input) {
89 std::vector<FontLanguage> result;
90 size_t currentIdx = 0;
91 size_t commaLoc = 0;
92 char langTag[ULOC_FULLNAME_CAPACITY];
93 std::unordered_set<uint64_t> seen;
94 std::string locale(input.size(), 0);
95
96 while ((commaLoc = input.find_first_of(',', currentIdx)) !=
97 std::string::npos) {
98 locale.assign(input, currentIdx, commaLoc - currentIdx);
99 currentIdx = commaLoc + 1;
100 size_t length = toLanguageTag(langTag, ULOC_FULLNAME_CAPACITY, locale);
101 FontLanguage lang(langTag, length);
102 uint64_t identifier = lang.getIdentifier();
103 if (!lang.isUnsupported() && seen.count(identifier) == 0) {
104 result.push_back(lang);
105 if (result.size() == FONT_LANGUAGES_LIMIT) {
106 break;
107 }
108 seen.insert(identifier);
109 }
110 }
111 if (result.size() < FONT_LANGUAGES_LIMIT) {
112 locale.assign(input, currentIdx, input.size() - currentIdx);
113 size_t length = toLanguageTag(langTag, ULOC_FULLNAME_CAPACITY, locale);
114 FontLanguage lang(langTag, length);
115 uint64_t identifier = lang.getIdentifier();
116 if (!lang.isUnsupported() && seen.count(identifier) == 0) {
117 result.push_back(lang);
118 }
119 }
120 return result;
121 }
122
123 // static
getId(const std::string & languages)124 uint32_t FontLanguageListCache::getId(const std::string& languages) {
125 FontLanguageListCache* inst = FontLanguageListCache::getInstance();
126 std::unordered_map<std::string, uint32_t>::const_iterator it =
127 inst->mLanguageListLookupTable.find(languages);
128 if (it != inst->mLanguageListLookupTable.end()) {
129 return it->second;
130 }
131
132 // Given language list is not in cache. Insert it and return newly assigned
133 // ID.
134 const uint32_t nextId = inst->mLanguageLists.size();
135 FontLanguages fontLanguages(parseLanguageList(languages));
136 if (fontLanguages.empty()) {
137 return kEmptyListId;
138 }
139 inst->mLanguageLists.push_back(std::move(fontLanguages));
140 inst->mLanguageListLookupTable.insert(std::make_pair(languages, nextId));
141 return nextId;
142 }
143
144 // static
getById(uint32_t id)145 const FontLanguages& FontLanguageListCache::getById(uint32_t id) {
146 FontLanguageListCache* inst = FontLanguageListCache::getInstance();
147 LOG_ALWAYS_FATAL_IF(id >= inst->mLanguageLists.size(),
148 "Lookup by unknown language list ID.");
149 return inst->mLanguageLists[id];
150 }
151
152 // static
getInstance()153 FontLanguageListCache* FontLanguageListCache::getInstance() {
154 assertMinikinLocked();
155 static FontLanguageListCache* instance = nullptr;
156 if (instance == nullptr) {
157 instance = new FontLanguageListCache();
158
159 // Insert an empty language list for mapping default language list to
160 // kEmptyListId. The default language list has only one FontLanguage and it
161 // is the unsupported language.
162 instance->mLanguageLists.push_back(FontLanguages());
163 instance->mLanguageListLookupTable.insert(std::make_pair("", kEmptyListId));
164 }
165 return instance;
166 }
167
168 } // namespace minikin
169