1/* 2 * Copyright (C) 2016 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29#include "private/icu.h" 30 31#include <dirent.h> 32#include <dlfcn.h> 33#include <pthread.h> 34#include <stdlib.h> 35#include <string.h> 36 37#include <async_safe/log.h> 38 39// Allowed icu4c version numbers are in the range [44, 999]. 40// Gingerbread's icu4c 4.4 is the minimum supported ICU version. 41static constexpr auto ICUDATA_VERSION_MIN_LENGTH = 2; 42static constexpr auto ICUDATA_VERSION_MAX_LENGTH = 3; 43static constexpr auto ICUDATA_VERSION_MIN = 44; 44 45static char g_icudata_version[ICUDATA_VERSION_MAX_LENGTH + 1]; 46 47static void* g_libicuuc_handle = nullptr; 48 49static int __icu_dat_file_filter(const dirent* dirp) { 50 const char* name = dirp->d_name; 51 52 // Is the name the right length to match 'icudt(\d\d\d)l.dat'? 53 const size_t len = strlen(name); 54 if (len < 10 + ICUDATA_VERSION_MIN_LENGTH || len > 10 + ICUDATA_VERSION_MAX_LENGTH) return 0; 55 56 return !strncmp(name, "icudt", 5) && !strncmp(&name[len - 5], "l.dat", 5); 57} 58 59static bool __find_icu() { 60 dirent** namelist = nullptr; 61 int n = scandir("/system/usr/icu", &namelist, &__icu_dat_file_filter, alphasort); 62 int max_version = -1; 63 while (n--) { 64 // We prefer the latest version available. 65 int version = atoi(&namelist[n]->d_name[strlen("icudt")]); 66 if (version != 0 && version > max_version) max_version = version; 67 free(namelist[n]); 68 } 69 free(namelist); 70 71 if (max_version < ICUDATA_VERSION_MIN) { 72 async_safe_write_log(ANDROID_LOG_ERROR, "bionic-icu", "couldn't find an ICU .dat file"); 73 return false; 74 } 75 76 snprintf(g_icudata_version, sizeof(g_icudata_version), "_%d", max_version); 77 78 g_libicuuc_handle = dlopen("libicuuc.so", RTLD_LOCAL); 79 if (g_libicuuc_handle == nullptr) { 80 async_safe_format_log(ANDROID_LOG_ERROR, "bionic-icu", "couldn't open libicuuc.so: %s", 81 dlerror()); 82 return false; 83 } 84 85 return true; 86} 87 88void* __find_icu_symbol(const char* symbol_name) { 89 static bool found_icu = __find_icu(); 90 if (!found_icu) return nullptr; 91 92 char versioned_symbol_name[strlen(symbol_name) + sizeof(g_icudata_version)]; 93 snprintf(versioned_symbol_name, sizeof(versioned_symbol_name), "%s%s", 94 symbol_name, g_icudata_version); 95 96 void* symbol = dlsym(g_libicuuc_handle, versioned_symbol_name); 97 if (symbol == nullptr) { 98 async_safe_format_log(ANDROID_LOG_ERROR, "bionic-icu", "couldn't find %s", 99 versioned_symbol_name); 100 } 101 return symbol; 102} 103