| /* |
| * Copyright (C) 2016 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 <cstdint> |
| #include <cstdlib> |
| #include <cstring> |
| #include <string> |
| #include <unordered_map> |
| #include <unordered_set> |
| |
| #include <androidfw/LocaleData.h> |
| |
| namespace android { |
| |
| #include "LocaleDataTables.cpp" |
| |
| inline uint32_t packLocale(const char* language, const char* region) { |
| return (((uint8_t) language[0]) << 24u) | (((uint8_t) language[1]) << 16u) | |
| (((uint8_t) region[0]) << 8u) | ((uint8_t) region[1]); |
| } |
| |
| inline uint32_t dropRegion(uint32_t packed_locale) { |
| return packed_locale & 0xFFFF0000lu; |
| } |
| |
| inline bool hasRegion(uint32_t packed_locale) { |
| return (packed_locale & 0x0000FFFFlu) != 0; |
| } |
| |
| const size_t SCRIPT_LENGTH = 4; |
| const size_t SCRIPT_PARENTS_COUNT = sizeof(SCRIPT_PARENTS)/sizeof(SCRIPT_PARENTS[0]); |
| const uint32_t PACKED_ROOT = 0; // to represent the root locale |
| |
| uint32_t findParent(uint32_t packed_locale, const char* script) { |
| if (hasRegion(packed_locale)) { |
| for (size_t i = 0; i < SCRIPT_PARENTS_COUNT; i++) { |
| if (memcmp(script, SCRIPT_PARENTS[i].script, SCRIPT_LENGTH) == 0) { |
| auto map = SCRIPT_PARENTS[i].map; |
| auto lookup_result = map->find(packed_locale); |
| if (lookup_result != map->end()) { |
| return lookup_result->second; |
| } |
| break; |
| } |
| } |
| return dropRegion(packed_locale); |
| } |
| return PACKED_ROOT; |
| } |
| |
| // Find the ancestors of a locale, and fill 'out' with it (assumes out has enough |
| // space). If any of the members of stop_list was seen, write it in the |
| // output but stop afterwards. |
| // |
| // This also outputs the index of the last written ancestor in the stop_list |
| // to stop_list_index, which will be -1 if it is not found in the stop_list. |
| // |
| // Returns the number of ancestors written in the output, which is always |
| // at least one. |
| size_t findAncestors(uint32_t* out, ssize_t* stop_list_index, |
| uint32_t packed_locale, const char* script, |
| const uint32_t* stop_list, size_t stop_set_length) { |
| uint32_t ancestor = packed_locale; |
| size_t count = 0; |
| do { |
| out[count++] = ancestor; |
| for (size_t i = 0; i < stop_set_length; i++) { |
| if (stop_list[i] == ancestor) { |
| *stop_list_index = (ssize_t) i; |
| return count; |
| } |
| } |
| ancestor = findParent(ancestor, script); |
| } while (ancestor != PACKED_ROOT); |
| *stop_list_index = (ssize_t) -1; |
| return count; |
| } |
| |
| size_t findDistance(uint32_t supported, |
| const char* script, |
| const uint32_t* request_ancestors, |
| size_t request_ancestors_count) { |
| uint32_t supported_ancestors[MAX_PARENT_DEPTH+1]; |
| ssize_t request_ancestors_index; |
| const size_t supported_ancestor_count = findAncestors( |
| supported_ancestors, &request_ancestors_index, |
| supported, script, |
| request_ancestors, request_ancestors_count); |
| // Since both locales share the same root, there will always be a shared |
| // ancestor, so the distance in the parent tree is the sum of the distance |
| // of 'supported' to the lowest common ancestor (number of ancestors |
| // written for 'supported' minus 1) plus the distance of 'request' to the |
| // lowest common ancestor (the index of the ancestor in request_ancestors). |
| return supported_ancestor_count + request_ancestors_index - 1; |
| } |
| |
| inline bool isRepresentative(uint32_t language_and_region, const char* script) { |
| const uint64_t packed_locale = ( |
| (((uint64_t) language_and_region) << 32u) | |
| (((uint64_t) script[0]) << 24u) | |
| (((uint64_t) script[1]) << 16u) | |
| (((uint64_t) script[2]) << 8u) | |
| ((uint64_t) script[3])); |
| |
| return (REPRESENTATIVE_LOCALES.count(packed_locale) != 0); |
| } |
| |
| int localeDataCompareRegions( |
| const char* left_region, const char* right_region, |
| const char* requested_language, const char* requested_script, |
| const char* requested_region) { |
| |
| if (left_region[0] == right_region[0] && left_region[1] == right_region[1]) { |
| return 0; |
| } |
| const uint32_t left = packLocale(requested_language, left_region); |
| const uint32_t right = packLocale(requested_language, right_region); |
| const uint32_t request = packLocale(requested_language, requested_region); |
| |
| uint32_t request_ancestors[MAX_PARENT_DEPTH+1]; |
| ssize_t left_right_index; |
| // Find the parents of the request, but stop as soon as we saw left or right |
| const uint32_t left_and_right[] = {left, right}; |
| const size_t ancestor_count = findAncestors( |
| request_ancestors, &left_right_index, |
| request, requested_script, |
| left_and_right, sizeof(left_and_right)/sizeof(left_and_right[0])); |
| if (left_right_index == 0) { // We saw left earlier |
| return 1; |
| } |
| if (left_right_index == 1) { // We saw right earlier |
| return -1; |
| } |
| |
| // If we are here, neither left nor right are an ancestor of the |
| // request. This means that all the ancestors have been computed and |
| // the last ancestor is just the language by itself. We will use the |
| // distance in the parent tree for determining the better match. |
| const size_t left_distance = findDistance( |
| left, requested_script, request_ancestors, ancestor_count); |
| const size_t right_distance = findDistance( |
| right, requested_script, request_ancestors, ancestor_count); |
| if (left_distance != right_distance) { |
| return (int) right_distance - (int) left_distance; // smaller distance is better |
| } |
| |
| // If we are here, left and right are equidistant from the request. We will |
| // try and see if any of them is a representative locale. |
| const bool left_is_representative = isRepresentative(left, requested_script); |
| const bool right_is_representative = isRepresentative(right, requested_script); |
| if (left_is_representative != right_is_representative) { |
| return (int) left_is_representative - (int) right_is_representative; |
| } |
| |
| // We have no way of figuring out which locale is a better match. For |
| // the sake of stability, we consider the locale with the lower region |
| // code (in dictionary order) better, with two-letter codes before |
| // three-digit codes (since two-letter codes are more specific). |
| return (int64_t) right - (int64_t) left; |
| } |
| |
| void localeDataComputeScript(char out[4], const char* language, const char* region) { |
| if (language[0] == '\0') { |
| memset(out, '\0', SCRIPT_LENGTH); |
| return; |
| } |
| uint32_t lookup_key = packLocale(language, region); |
| auto lookup_result = LIKELY_SCRIPTS.find(lookup_key); |
| if (lookup_result == LIKELY_SCRIPTS.end()) { |
| // We couldn't find the locale. Let's try without the region |
| if (region[0] != '\0') { |
| lookup_key = dropRegion(lookup_key); |
| lookup_result = LIKELY_SCRIPTS.find(lookup_key); |
| if (lookup_result != LIKELY_SCRIPTS.end()) { |
| memcpy(out, SCRIPT_CODES[lookup_result->second], SCRIPT_LENGTH); |
| return; |
| } |
| } |
| // We don't know anything about the locale |
| memset(out, '\0', SCRIPT_LENGTH); |
| return; |
| } else { |
| // We found the locale. |
| memcpy(out, SCRIPT_CODES[lookup_result->second], SCRIPT_LENGTH); |
| } |
| } |
| |
| } // namespace android |