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