1 /* 2 * Copyright (C) 2011 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 #include "file_utils.h" 18 19 #include <inttypes.h> 20 #include <sys/stat.h> 21 #include <sys/types.h> 22 #include <sys/wait.h> 23 #include <unistd.h> 24 25 // We need dladdr. 26 #ifndef __APPLE__ 27 #ifndef _GNU_SOURCE 28 #define _GNU_SOURCE 29 #define DEFINED_GNU_SOURCE 30 #endif 31 #include <dlfcn.h> 32 #include <libgen.h> 33 #ifdef DEFINED_GNU_SOURCE 34 #undef _GNU_SOURCE 35 #undef DEFINED_GNU_SOURCE 36 #endif 37 #endif 38 39 40 #include <memory> 41 42 #include "android-base/stringprintf.h" 43 #include "android-base/strings.h" 44 45 #include "base/bit_utils.h" 46 #include "base/stl_util.h" 47 #include "base/os.h" 48 #include "base/unix_file/fd_file.h" 49 #include "dex/dex_file_loader.h" 50 #include "globals.h" 51 52 #if defined(__APPLE__) 53 #include <crt_externs.h> 54 #include <sys/syscall.h> 55 #include "AvailabilityMacros.h" // For MAC_OS_X_VERSION_MAX_ALLOWED 56 #endif 57 58 #if defined(__linux__) 59 #include <linux/unistd.h> 60 #endif 61 62 namespace art { 63 64 using android::base::StringAppendF; 65 using android::base::StringPrintf; 66 67 bool ReadFileToString(const std::string& file_name, std::string* result) { 68 File file(file_name, O_RDONLY, false); 69 if (!file.IsOpened()) { 70 return false; 71 } 72 73 std::vector<char> buf(8 * KB); 74 while (true) { 75 int64_t n = TEMP_FAILURE_RETRY(read(file.Fd(), &buf[0], buf.size())); 76 if (n == -1) { 77 return false; 78 } 79 if (n == 0) { 80 return true; 81 } 82 result->append(&buf[0], n); 83 } 84 } 85 86 bool PrintFileToLog(const std::string& file_name, android::base::LogSeverity level) { 87 File file(file_name, O_RDONLY, false); 88 if (!file.IsOpened()) { 89 return false; 90 } 91 92 constexpr size_t kBufSize = 256; // Small buffer. Avoid stack overflow and stack size warnings. 93 char buf[kBufSize + 1]; // +1 for terminator. 94 size_t filled_to = 0; 95 while (true) { 96 DCHECK_LT(filled_to, kBufSize); 97 int64_t n = TEMP_FAILURE_RETRY(read(file.Fd(), &buf[filled_to], kBufSize - filled_to)); 98 if (n <= 0) { 99 // Print the rest of the buffer, if it exists. 100 if (filled_to > 0) { 101 buf[filled_to] = 0; 102 LOG(level) << buf; 103 } 104 return n == 0; 105 } 106 // Scan for '\n'. 107 size_t i = filled_to; 108 bool found_newline = false; 109 for (; i < filled_to + n; ++i) { 110 if (buf[i] == '\n') { 111 // Found a line break, that's something to print now. 112 buf[i] = 0; 113 LOG(level) << buf; 114 // Copy the rest to the front. 115 if (i + 1 < filled_to + n) { 116 memmove(&buf[0], &buf[i + 1], filled_to + n - i - 1); 117 filled_to = filled_to + n - i - 1; 118 } else { 119 filled_to = 0; 120 } 121 found_newline = true; 122 break; 123 } 124 } 125 if (found_newline) { 126 continue; 127 } else { 128 filled_to += n; 129 // Check if we must flush now. 130 if (filled_to == kBufSize) { 131 buf[kBufSize] = 0; 132 LOG(level) << buf; 133 filled_to = 0; 134 } 135 } 136 } 137 } 138 139 std::string GetAndroidRootSafe(std::string* error_msg) { 140 // Prefer ANDROID_ROOT if it's set. 141 const char* android_dir = getenv("ANDROID_ROOT"); 142 if (android_dir != nullptr) { 143 if (!OS::DirectoryExists(android_dir)) { 144 *error_msg = StringPrintf("Failed to find ANDROID_ROOT directory %s", android_dir); 145 return ""; 146 } 147 return android_dir; 148 } 149 150 // Check where libart is from, and derive from there. Only do this for non-Mac. 151 #ifndef __APPLE__ 152 { 153 Dl_info info; 154 if (dladdr(reinterpret_cast<const void*>(&GetAndroidRootSafe), /* out */ &info) != 0) { 155 // Make a duplicate of the fname so dirname can modify it. 156 UniqueCPtr<char> fname(strdup(info.dli_fname)); 157 158 char* dir1 = dirname(fname.get()); // This is the lib directory. 159 char* dir2 = dirname(dir1); // This is the "system" directory. 160 if (OS::DirectoryExists(dir2)) { 161 std::string tmp = dir2; // Make a copy here so that fname can be released. 162 return tmp; 163 } 164 } 165 } 166 #endif 167 168 // Try "/system". 169 if (!OS::DirectoryExists("/system")) { 170 *error_msg = "Failed to find ANDROID_ROOT directory /system"; 171 return ""; 172 } 173 return "/system"; 174 } 175 176 std::string GetAndroidRoot() { 177 std::string error_msg; 178 std::string ret = GetAndroidRootSafe(&error_msg); 179 if (ret.empty()) { 180 LOG(FATAL) << error_msg; 181 UNREACHABLE(); 182 } 183 return ret; 184 } 185 186 187 static const char* GetAndroidDirSafe(const char* env_var, 188 const char* default_dir, 189 std::string* error_msg) { 190 const char* android_dir = getenv(env_var); 191 if (android_dir == nullptr) { 192 if (OS::DirectoryExists(default_dir)) { 193 android_dir = default_dir; 194 } else { 195 *error_msg = StringPrintf("%s not set and %s does not exist", env_var, default_dir); 196 return nullptr; 197 } 198 } 199 if (!OS::DirectoryExists(android_dir)) { 200 *error_msg = StringPrintf("Failed to find %s directory %s", env_var, android_dir); 201 return nullptr; 202 } 203 return android_dir; 204 } 205 206 static const char* GetAndroidDir(const char* env_var, const char* default_dir) { 207 std::string error_msg; 208 const char* dir = GetAndroidDirSafe(env_var, default_dir, &error_msg); 209 if (dir != nullptr) { 210 return dir; 211 } else { 212 LOG(FATAL) << error_msg; 213 return nullptr; 214 } 215 } 216 217 const char* GetAndroidData() { 218 return GetAndroidDir("ANDROID_DATA", "/data"); 219 } 220 221 const char* GetAndroidDataSafe(std::string* error_msg) { 222 return GetAndroidDirSafe("ANDROID_DATA", "/data", error_msg); 223 } 224 225 std::string GetDefaultBootImageLocation(std::string* error_msg) { 226 std::string android_root = GetAndroidRootSafe(error_msg); 227 if (android_root.empty()) { 228 return ""; 229 } 230 return StringPrintf("%s/framework/boot.art", android_root.c_str()); 231 } 232 233 void GetDalvikCache(const char* subdir, const bool create_if_absent, std::string* dalvik_cache, 234 bool* have_android_data, bool* dalvik_cache_exists, bool* is_global_cache) { 235 CHECK(subdir != nullptr); 236 std::string error_msg; 237 const char* android_data = GetAndroidDataSafe(&error_msg); 238 if (android_data == nullptr) { 239 *have_android_data = false; 240 *dalvik_cache_exists = false; 241 *is_global_cache = false; 242 return; 243 } else { 244 *have_android_data = true; 245 } 246 const std::string dalvik_cache_root(StringPrintf("%s/dalvik-cache/", android_data)); 247 *dalvik_cache = dalvik_cache_root + subdir; 248 *dalvik_cache_exists = OS::DirectoryExists(dalvik_cache->c_str()); 249 *is_global_cache = strcmp(android_data, "/data") == 0; 250 if (create_if_absent && !*dalvik_cache_exists && !*is_global_cache) { 251 // Don't create the system's /data/dalvik-cache/... because it needs special permissions. 252 *dalvik_cache_exists = ((mkdir(dalvik_cache_root.c_str(), 0700) == 0 || errno == EEXIST) && 253 (mkdir(dalvik_cache->c_str(), 0700) == 0 || errno == EEXIST)); 254 } 255 } 256 257 std::string GetDalvikCache(const char* subdir) { 258 CHECK(subdir != nullptr); 259 const char* android_data = GetAndroidData(); 260 const std::string dalvik_cache_root(StringPrintf("%s/dalvik-cache/", android_data)); 261 const std::string dalvik_cache = dalvik_cache_root + subdir; 262 if (!OS::DirectoryExists(dalvik_cache.c_str())) { 263 // TODO: Check callers. Traditional behavior is to not abort. 264 return ""; 265 } 266 return dalvik_cache; 267 } 268 269 bool GetDalvikCacheFilename(const char* location, const char* cache_location, 270 std::string* filename, std::string* error_msg) { 271 if (location[0] != '/') { 272 *error_msg = StringPrintf("Expected path in location to be absolute: %s", location); 273 return false; 274 } 275 std::string cache_file(&location[1]); // skip leading slash 276 if (!android::base::EndsWith(location, ".dex") && 277 !android::base::EndsWith(location, ".art") && 278 !android::base::EndsWith(location, ".oat")) { 279 cache_file += "/"; 280 cache_file += DexFileLoader::kClassesDex; 281 } 282 std::replace(cache_file.begin(), cache_file.end(), '/', '@'); 283 *filename = StringPrintf("%s/%s", cache_location, cache_file.c_str()); 284 return true; 285 } 286 287 std::string GetVdexFilename(const std::string& oat_location) { 288 return ReplaceFileExtension(oat_location, "vdex"); 289 } 290 291 static void InsertIsaDirectory(const InstructionSet isa, std::string* filename) { 292 // in = /foo/bar/baz 293 // out = /foo/bar/<isa>/baz 294 size_t pos = filename->rfind('/'); 295 CHECK_NE(pos, std::string::npos) << *filename << " " << isa; 296 filename->insert(pos, "/", 1); 297 filename->insert(pos + 1, GetInstructionSetString(isa)); 298 } 299 300 std::string GetSystemImageFilename(const char* location, const InstructionSet isa) { 301 // location = /system/framework/boot.art 302 // filename = /system/framework/<isa>/boot.art 303 std::string filename(location); 304 InsertIsaDirectory(isa, &filename); 305 return filename; 306 } 307 308 std::string ReplaceFileExtension(const std::string& filename, const std::string& new_extension) { 309 const size_t last_ext = filename.find_last_of('.'); 310 if (last_ext == std::string::npos) { 311 return filename + "." + new_extension; 312 } else { 313 return filename.substr(0, last_ext + 1) + new_extension; 314 } 315 } 316 317 bool LocationIsOnSystem(const char* path) { 318 UniqueCPtr<const char[]> full_path(realpath(path, nullptr)); 319 return full_path != nullptr && 320 android::base::StartsWith(full_path.get(), GetAndroidRoot().c_str()); 321 } 322 323 bool LocationIsOnSystemFramework(const char* full_path) { 324 std::string error_msg; 325 std::string root_path = GetAndroidRootSafe(&error_msg); 326 if (root_path.empty()) { 327 // Could not find Android root. 328 // TODO(dbrazdil): change to stricter GetAndroidRoot() once b/76452688 is resolved. 329 return false; 330 } 331 std::string framework_path = root_path + "/framework/"; 332 return android::base::StartsWith(full_path, framework_path); 333 } 334 335 } // namespace art 336
