1 /* 2 * Copyright (C) 2006 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 // 18 // Asset management class. AssetManager objects are thread-safe. 19 // 20 #ifndef __LIBS_ASSETMANAGER_H 21 #define __LIBS_ASSETMANAGER_H 22 23 #include <androidfw/Asset.h> 24 #include <androidfw/AssetDir.h> 25 #include <androidfw/ZipFileRO.h> 26 #include <utils/KeyedVector.h> 27 #include <utils/SortedVector.h> 28 #include <utils/String16.h> 29 #include <utils/String8.h> 30 #include <utils/threads.h> 31 #include <utils/Vector.h> 32 33 /* 34 * Native-app access is via the opaque typedef struct AAssetManager in the C namespace. 35 */ 36 #ifdef __cplusplus 37 extern "C" { 38 #endif 39 40 struct AAssetManager { }; 41 42 #ifdef __cplusplus 43 }; 44 #endif 45 46 47 /* 48 * Now the proper C++ android-namespace definitions 49 */ 50 51 namespace android { 52 53 class Asset; // fwd decl for things that include Asset.h first 54 class ResTable; 55 struct ResTable_config; 56 57 /* 58 * Every application that uses assets needs one instance of this. A 59 * single instance may be shared across multiple threads, and a single 60 * thread may have more than one instance (the latter is discouraged). 61 * 62 * The purpose of the AssetManager is to create Asset objects. To do 63 * this efficiently it may cache information about the locations of 64 * files it has seen. This can be controlled with the "cacheMode" 65 * argument. 66 * 67 * The asset hierarchy may be examined like a filesystem, using 68 * AssetDir objects to peruse a single directory. 69 */ 70 class AssetManager : public AAssetManager { 71 public: 72 static const char* RESOURCES_FILENAME; 73 static const char* IDMAP_BIN; 74 static const char* OVERLAY_DIR; 75 static const char* TARGET_PACKAGE_NAME; 76 static const char* TARGET_APK_PATH; 77 static const char* IDMAP_DIR; 78 79 typedef enum CacheMode { 80 CACHE_UNKNOWN = 0, 81 CACHE_OFF, // don't try to cache file locations 82 CACHE_DEFER, // construct cache as pieces are needed 83 //CACHE_SCAN, // scan full(!) asset hierarchy at init() time 84 } CacheMode; 85 86 AssetManager(CacheMode cacheMode = CACHE_OFF); 87 virtual ~AssetManager(void); 88 89 static int32_t getGlobalCount(); 90 91 /* 92 * Add a new source for assets. This can be called multiple times to 93 * look in multiple places for assets. It can be either a directory (for 94 * finding assets as raw files on the disk) or a ZIP file. This newly 95 * added asset path will be examined first when searching for assets, 96 * before any that were previously added. 97 * 98 * Returns "true" on success, "false" on failure. If 'cookie' is non-NULL, 99 * then on success, *cookie is set to the value corresponding to the 100 * newly-added asset source. 101 */ 102 bool addAssetPath(const String8& path, int32_t* cookie); 103 bool addOverlayPath(const String8& path, int32_t* cookie); 104 105 /* 106 * Convenience for adding the standard system assets. Uses the 107 * ANDROID_ROOT environment variable to find them. 108 */ 109 bool addDefaultAssets(); 110 111 /* 112 * Iterate over the asset paths in this manager. (Previously 113 * added via addAssetPath() and addDefaultAssets().) On first call, 114 * 'cookie' must be 0, resulting in the first cookie being returned. 115 * Each next cookie will be returned there-after, until -1 indicating 116 * the end has been reached. 117 */ 118 int32_t nextAssetPath(const int32_t cookie) const; 119 120 /* 121 * Return an asset path in the manager. 'which' must be between 0 and 122 * countAssetPaths(). 123 */ 124 String8 getAssetPath(const int32_t cookie) const; 125 126 /* 127 * Set the current locale and vendor. The locale can change during 128 * the lifetime of an AssetManager if the user updates the device's 129 * language setting. The vendor is less likely to change. 130 * 131 * Pass in NULL to indicate no preference. 132 */ 133 void setLocale(const char* locale); 134 void setVendor(const char* vendor); 135 136 /* 137 * Choose screen orientation for resources values returned. 138 */ 139 void setConfiguration(const ResTable_config& config, const char* locale = NULL); 140 141 void getConfiguration(ResTable_config* outConfig) const; 142 143 typedef Asset::AccessMode AccessMode; // typing shortcut 144 145 /* 146 * Open an asset. 147 * 148 * This will search through locale-specific and vendor-specific 149 * directories and packages to find the file. 150 * 151 * The object returned does not depend on the AssetManager. It should 152 * be freed by calling Asset::close(). 153 */ 154 Asset* open(const char* fileName, AccessMode mode); 155 156 /* 157 * Open a non-asset file as an asset. 158 * 159 * This is for opening files that are included in an asset package 160 * but aren't assets. These sit outside the usual "locale/vendor" 161 * path hierarchy, and will not be seen by "AssetDir" or included 162 * in our filename cache. 163 */ 164 Asset* openNonAsset(const char* fileName, AccessMode mode, int32_t* outCookie = NULL); 165 166 /* 167 * Explicit non-asset file. The file explicitly named by the cookie (the 168 * resource set to look in) and fileName will be opened and returned. 169 */ 170 Asset* openNonAsset(const int32_t cookie, const char* fileName, AccessMode mode); 171 172 /* 173 * Open a directory within the asset hierarchy. 174 * 175 * The contents of the directory are an amalgam of vendor-specific, 176 * locale-specific, and generic assets stored loosely or in asset 177 * packages. Depending on the cache setting and previous accesses, 178 * this call may incur significant disk overhead. 179 * 180 * To open the top-level directory, pass in "". 181 */ 182 AssetDir* openDir(const char* dirName); 183 184 /* 185 * Open a directory within a particular path of the asset manager. 186 * 187 * The contents of the directory are an amalgam of vendor-specific, 188 * locale-specific, and generic assets stored loosely or in asset 189 * packages. Depending on the cache setting and previous accesses, 190 * this call may incur significant disk overhead. 191 * 192 * To open the top-level directory, pass in "". 193 */ 194 AssetDir* openNonAssetDir(const int32_t cookie, const char* dirName); 195 196 /* 197 * Get the type of a file in the asset hierarchy. They will either 198 * be "regular" or "directory". [Currently only works for "regular".] 199 * 200 * Can also be used as a quick test for existence of a file. 201 */ 202 FileType getFileType(const char* fileName); 203 204 /* 205 * Return the complete resource table to find things in the package. 206 */ 207 const ResTable& getResources(bool required = true) const; 208 209 /* 210 * Discard cached filename information. This only needs to be called 211 * if somebody has updated the set of "loose" files, and we want to 212 * discard our cached notion of what's where. 213 */ 214 void purge(void) { purgeFileNameCacheLocked(); } 215 216 /* 217 * Return true if the files this AssetManager references are all 218 * up-to-date (have not been changed since it was created). If false 219 * is returned, you will need to create a new AssetManager to get 220 * the current data. 221 */ 222 bool isUpToDate(); 223 224 /** 225 * Get the known locales for this asset manager object. 226 */ 227 void getLocales(Vector<String8>* locales) const; 228 229 /** 230 * Generate idmap data to translate resources IDs between a package and a 231 * corresponding overlay package. 232 */ 233 bool createIdmap(const char* targetApkPath, const char* overlayApkPath, 234 uint32_t targetCrc, uint32_t overlayCrc, uint32_t** outData, size_t* outSize); 235 236 private: 237 struct asset_path 238 { 239 String8 path; 240 FileType type; 241 String8 idmap; 242 }; 243 244 Asset* openInPathLocked(const char* fileName, AccessMode mode, 245 const asset_path& path); 246 Asset* openNonAssetInPathLocked(const char* fileName, AccessMode mode, 247 const asset_path& path); 248 Asset* openInLocaleVendorLocked(const char* fileName, AccessMode mode, 249 const asset_path& path, const char* locale, const char* vendor); 250 String8 createPathNameLocked(const asset_path& path, const char* locale, 251 const char* vendor); 252 String8 createPathNameLocked(const asset_path& path, const char* rootDir); 253 String8 createZipSourceNameLocked(const String8& zipFileName, 254 const String8& dirName, const String8& fileName); 255 256 ZipFileRO* getZipFileLocked(const asset_path& path); 257 Asset* openAssetFromFileLocked(const String8& fileName, AccessMode mode); 258 Asset* openAssetFromZipLocked(const ZipFileRO* pZipFile, 259 const ZipEntryRO entry, AccessMode mode, const String8& entryName); 260 261 bool scanAndMergeDirLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 262 const asset_path& path, const char* rootDir, const char* dirName); 263 SortedVector<AssetDir::FileInfo>* scanDirLocked(const String8& path); 264 bool scanAndMergeZipLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 265 const asset_path& path, const char* rootDir, const char* dirName); 266 void mergeInfoLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 267 const SortedVector<AssetDir::FileInfo>* pContents); 268 269 void loadFileNameCacheLocked(void); 270 void fncScanLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 271 const char* dirName); 272 bool fncScanAndMergeDirLocked( 273 SortedVector<AssetDir::FileInfo>* pMergedInfo, 274 const asset_path& path, const char* locale, const char* vendor, 275 const char* dirName); 276 void purgeFileNameCacheLocked(void); 277 278 const ResTable* getResTable(bool required = true) const; 279 void setLocaleLocked(const char* locale); 280 void updateResourceParamsLocked() const; 281 bool appendPathToResTable(const asset_path& ap) const; 282 283 Asset* openIdmapLocked(const struct asset_path& ap) const; 284 285 void addSystemOverlays(const char* pathOverlaysList, const String8& targetPackagePath, 286 ResTable* sharedRes, size_t offset) const; 287 288 class SharedZip : public RefBase { 289 public: 290 static sp<SharedZip> get(const String8& path, bool createIfNotPresent = true); 291 292 ZipFileRO* getZip(); 293 294 Asset* getResourceTableAsset(); 295 Asset* setResourceTableAsset(Asset* asset); 296 297 ResTable* getResourceTable(); 298 ResTable* setResourceTable(ResTable* res); 299 300 bool isUpToDate(); 301 302 void addOverlay(const asset_path& ap); 303 bool getOverlay(size_t idx, asset_path* out) const; 304 305 protected: 306 ~SharedZip(); 307 308 private: 309 SharedZip(const String8& path, time_t modWhen); 310 SharedZip(); // <-- not implemented 311 312 String8 mPath; 313 ZipFileRO* mZipFile; 314 time_t mModWhen; 315 316 Asset* mResourceTableAsset; 317 ResTable* mResourceTable; 318 319 Vector<asset_path> mOverlays; 320 321 static Mutex gLock; 322 static DefaultKeyedVector<String8, wp<SharedZip> > gOpen; 323 }; 324 325 /* 326 * Manage a set of Zip files. For each file we need a pointer to the 327 * ZipFile and a time_t with the file's modification date. 328 * 329 * We currently only have two zip files (current app, "common" app). 330 * (This was originally written for 8, based on app/locale/vendor.) 331 */ 332 class ZipSet { 333 public: 334 ZipSet(void); 335 ~ZipSet(void); 336 337 /* 338 * Return a ZipFileRO structure for a ZipFileRO with the specified 339 * parameters. 340 */ 341 ZipFileRO* getZip(const String8& path); 342 343 Asset* getZipResourceTableAsset(const String8& path); 344 Asset* setZipResourceTableAsset(const String8& path, Asset* asset); 345 346 ResTable* getZipResourceTable(const String8& path); 347 ResTable* setZipResourceTable(const String8& path, ResTable* res); 348 349 // generate path, e.g. "common/en-US-noogle.zip" 350 static String8 getPathName(const char* path); 351 352 bool isUpToDate(); 353 354 void addOverlay(const String8& path, const asset_path& overlay); 355 bool getOverlay(const String8& path, size_t idx, asset_path* out) const; 356 357 private: 358 void closeZip(int idx); 359 360 int getIndex(const String8& zip) const; 361 mutable Vector<String8> mZipPath; 362 mutable Vector<sp<SharedZip> > mZipFile; 363 }; 364 365 // Protect all internal state. 366 mutable Mutex mLock; 367 368 ZipSet mZipSet; 369 370 Vector<asset_path> mAssetPaths; 371 char* mLocale; 372 char* mVendor; 373 374 mutable ResTable* mResources; 375 ResTable_config* mConfig; 376 377 /* 378 * Cached data for "loose" files. This lets us avoid poking at the 379 * filesystem when searching for loose assets. Each entry is the 380 * "extended partial" path, e.g. "default/default/foo/bar.txt". The 381 * full set of files is present, including ".EXCLUDE" entries. 382 * 383 * We do not cache directory names. We don't retain the ".gz", 384 * because to our clients "foo" and "foo.gz" both look like "foo". 385 */ 386 CacheMode mCacheMode; // is the cache enabled? 387 bool mCacheValid; // clear when locale or vendor changes 388 SortedVector<AssetDir::FileInfo> mCache; 389 }; 390 391 }; // namespace android 392 393 #endif // __LIBS_ASSETMANAGER_H 394
