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 struct AAssetManager { }; 37 38 /* 39 * Now the proper C++ android-namespace definitions 40 */ 41 42 namespace android { 43 44 class Asset; // fwd decl for things that include Asset.h first 45 class ResTable; 46 struct ResTable_config; 47 48 /* 49 * Every application that uses assets needs one instance of this. A 50 * single instance may be shared across multiple threads, and a single 51 * thread may have more than one instance (the latter is discouraged). 52 * 53 * The purpose of the AssetManager is to create Asset objects. 54 * 55 * The asset hierarchy may be examined like a filesystem, using 56 * AssetDir objects to peruse a single directory. 57 */ 58 class AssetManager : public AAssetManager { 59 public: 60 static const char* RESOURCES_FILENAME; 61 static const char* IDMAP_BIN; 62 static const char* OVERLAY_DIR; 63 static const char* PRODUCT_OVERLAY_DIR; 64 /* 65 * If OVERLAY_THEME_DIR_PROPERTY is set, search for runtime resource overlay 66 * APKs in OVERLAY_DIR/<value of OVERLAY_THEME_DIR_PROPERTY> in addition to 67 * OVERLAY_DIR. 68 */ 69 static const char* OVERLAY_THEME_DIR_PROPERTY; 70 static const char* TARGET_PACKAGE_NAME; 71 static const char* TARGET_APK_PATH; 72 static const char* IDMAP_DIR; 73 74 AssetManager(); 75 virtual ~AssetManager(void); 76 77 static int32_t getGlobalCount(); 78 79 /* 80 * Add a new source for assets. This can be called multiple times to 81 * look in multiple places for assets. It can be either a directory (for 82 * finding assets as raw files on the disk) or a ZIP file. This newly 83 * added asset path will be examined first when searching for assets, 84 * before any that were previously added, the assets are added as shared 85 * library if appAsLib is true. 86 * 87 * Returns "true" on success, "false" on failure. If 'cookie' is non-NULL, 88 * then on success, *cookie is set to the value corresponding to the 89 * newly-added asset source. 90 */ 91 bool addAssetPath(const String8& path, int32_t* cookie, 92 bool appAsLib=false, bool isSystemAsset=false); 93 bool addOverlayPath(const String8& path, int32_t* cookie); 94 95 /* 96 * Add a new source for assets from an already open file descriptor. 97 * This does not give full AssetManager functionality for these assets, 98 * since the origin of the file is not known for purposes of sharing, 99 * overlay resolution, and other features. However it does allow you 100 * to do simple access to the contents of the given fd as an apk file. 101 * 102 * Returns "true" on success, "false" on failure. If 'cookie' is non-NULL, 103 * then on success, *cookie is set to the value corresponding to the 104 * newly-added asset source. 105 */ 106 bool addAssetFd(int fd, const String8& debugPathName, int32_t* cookie, 107 bool appAsLib=false, bool assume_ownership=true); 108 109 /* 110 * Convenience for adding the standard system assets. Uses the 111 * ANDROID_ROOT environment variable to find them. 112 */ 113 bool addDefaultAssets(); 114 115 /* 116 * Iterate over the asset paths in this manager. (Previously 117 * added via addAssetPath() and addDefaultAssets().) On first call, 118 * 'cookie' must be 0, resulting in the first cookie being returned. 119 * Each next cookie will be returned there-after, until -1 indicating 120 * the end has been reached. 121 */ 122 int32_t nextAssetPath(const int32_t cookie) const; 123 124 /* 125 * Return an asset path in the manager. 'cookie' must be a non-negative value 126 * previously returned from addAssetPath() or nextAssetPath(). 127 */ 128 String8 getAssetPath(const int32_t cookie) const; 129 130 /* 131 * Sets various device configuration parameters, like screen orientation, layout, 132 * size, locale, etc. 133 * The optional 'locale' string takes precedence over the locale within 'config' 134 * and must be in bcp47 format. 135 */ 136 void setConfiguration(const ResTable_config& config, const char* locale = NULL); 137 138 void getConfiguration(ResTable_config* outConfig) const; 139 140 typedef Asset::AccessMode AccessMode; // typing shortcut 141 142 /* 143 * Open an asset. 144 * 145 * The object returned does not depend on the AssetManager. It should 146 * be freed by calling Asset::close(). 147 */ 148 Asset* open(const char* fileName, AccessMode mode); 149 150 /* 151 * Open a non-asset file as an asset. 152 * 153 * This is for opening files that are included in an asset package 154 * but aren't assets. These sit outside the usual "assets/" 155 * path hierarchy, and will not be seen by "AssetDir". 156 */ 157 Asset* openNonAsset(const char* fileName, AccessMode mode, int32_t* outCookie = NULL); 158 159 /* 160 * Explicit non-asset file. The file explicitly named by the cookie (the 161 * resource set to look in) and fileName will be opened and returned. 162 */ 163 Asset* openNonAsset(const int32_t cookie, const char* fileName, AccessMode mode); 164 165 /* 166 * Open a directory within the asset hierarchy. 167 * 168 * To open the top-level directory, pass in "". 169 */ 170 AssetDir* openDir(const char* dirName); 171 172 /* 173 * Open a directory within a particular path of the asset manager. 174 * 175 * To open the top-level directory, pass in "". 176 */ 177 AssetDir* openNonAssetDir(const int32_t cookie, const char* dirName); 178 179 /* 180 * Get the type of a file in the asset hierarchy. They will either 181 * be "regular" or "directory". [Currently only works for "regular".] 182 * 183 * Can also be used as a quick test for existence of a file. 184 */ 185 FileType getFileType(const char* fileName); 186 187 /* 188 * Return the complete resource table to find things in the package. 189 */ 190 const ResTable& getResources(bool required = true) const; 191 192 /* 193 * Return true if the files this AssetManager references are all 194 * up-to-date (have not been changed since it was created). If false 195 * is returned, you will need to create a new AssetManager to get 196 * the current data. 197 */ 198 bool isUpToDate(); 199 200 /** 201 * Get the known locales for this asset manager object. 202 */ 203 void getLocales(Vector<String8>* locales, bool includeSystemLocales=true) const; 204 205 /** 206 * Generate idmap data to translate resources IDs between a package and a 207 * corresponding overlay package. 208 */ 209 bool createIdmap(const char* targetApkPath, const char* overlayApkPath, 210 uint32_t targetCrc, uint32_t overlayCrc, uint32_t** outData, size_t* outSize); 211 212 private: 213 class SharedZip; 214 215 struct asset_path 216 { asset_pathasset_path217 asset_path() : path(""), rawFd(-1), type(kFileTypeRegular), idmap(""), 218 isSystemOverlay(false), isSystemAsset(false), assumeOwnership(false) {} 219 String8 path; 220 int rawFd; 221 FileType type; 222 String8 idmap; 223 bool isSystemOverlay; 224 bool isSystemAsset; 225 bool assumeOwnership; 226 sp<SharedZip> zip; 227 }; 228 229 Asset* openNonAssetInPathLocked(const char* fileName, AccessMode mode, 230 asset_path& path); 231 String8 createPathNameLocked(const asset_path& path, const char* rootDir); 232 String8 createZipSourceNameLocked(const String8& zipFileName, 233 const String8& dirName, const String8& fileName); 234 235 ZipFileRO* getZipFileLocked(asset_path& path); 236 Asset* openAssetFromFileLocked(const String8& fileName, AccessMode mode); 237 Asset* openAssetFromZipLocked(const ZipFileRO* pZipFile, 238 const ZipEntryRO entry, AccessMode mode, const String8& entryName); 239 240 bool scanAndMergeDirLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 241 const asset_path& path, const char* rootDir, const char* dirName); 242 SortedVector<AssetDir::FileInfo>* scanDirLocked(const String8& path); 243 bool scanAndMergeZipLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 244 const asset_path& path, const char* rootDir, const char* dirName); 245 void mergeInfoLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, 246 const SortedVector<AssetDir::FileInfo>* pContents); 247 248 const ResTable* getResTable(bool required = true) const; 249 void setLocaleLocked(const char* locale); 250 void updateResourceParamsLocked() const; 251 bool appendPathToResTable(asset_path& ap, bool appAsLib=false) const; 252 253 Asset* openIdmapLocked(const struct asset_path& ap) const; 254 255 void addSystemOverlays(const char* pathOverlaysList, const String8& targetPackagePath, 256 ResTable* sharedRes, size_t offset) const; 257 258 class SharedZip : public RefBase { 259 public: 260 static sp<SharedZip> get(const String8& path, bool createIfNotPresent = true); 261 static sp<SharedZip> create(int fd, const String8& path); 262 263 ZipFileRO* getZip(); 264 265 Asset* getResourceTableAsset(); 266 Asset* setResourceTableAsset(Asset* asset); 267 268 ResTable* getResourceTable(); 269 ResTable* setResourceTable(ResTable* res); 270 271 bool isUpToDate(); 272 273 void addOverlay(const asset_path& ap); 274 bool getOverlay(size_t idx, asset_path* out) const; 275 276 protected: 277 ~SharedZip(); 278 279 private: 280 SharedZip(const String8& path, time_t modWhen); 281 SharedZip(int fd, const String8& path); 282 SharedZip(); // <-- not implemented 283 284 String8 mPath; 285 ZipFileRO* mZipFile; 286 time_t mModWhen; 287 288 Asset* mResourceTableAsset; 289 ResTable* mResourceTable; 290 291 Vector<asset_path> mOverlays; 292 293 static Mutex gLock; 294 static DefaultKeyedVector<String8, wp<SharedZip> > gOpen; 295 }; 296 297 /* 298 * Manage a set of Zip files. For each file we need a pointer to the 299 * ZipFile and a time_t with the file's modification date. 300 * 301 * We currently only have two zip files (current app, "common" app). 302 * (This was originally written for 8, based on app/locale/vendor.) 303 */ 304 class ZipSet { 305 public: 306 ZipSet() = default; 307 ~ZipSet(); 308 309 /* 310 * Return a ZipFileRO structure for a ZipFileRO with the specified 311 * parameters. 312 */ 313 ZipFileRO* getZip(const String8& path); 314 315 const sp<SharedZip> getSharedZip(const String8& path); 316 317 Asset* getZipResourceTableAsset(const String8& path); 318 Asset* setZipResourceTableAsset(const String8& path, Asset* asset); 319 320 ResTable* getZipResourceTable(const String8& path); 321 ResTable* setZipResourceTable(const String8& path, ResTable* res); 322 323 // generate path, e.g. "common/en-US-noogle.zip" 324 static String8 getPathName(const char* path); 325 326 bool isUpToDate(); 327 328 void addOverlay(const String8& path, const asset_path& overlay); 329 bool getOverlay(const String8& path, size_t idx, asset_path* out) const; 330 331 private: 332 void closeZip(int idx); 333 334 int getIndex(const String8& zip) const; 335 mutable Vector<String8> mZipPath; 336 mutable Vector<sp<SharedZip> > mZipFile; 337 }; 338 339 // Protect all internal state. 340 mutable Mutex mLock; 341 342 ZipSet mZipSet; 343 344 Vector<asset_path> mAssetPaths; 345 char* mLocale; 346 347 mutable ResTable* mResources; 348 ResTable_config* mConfig; 349 }; 350 351 }; // namespace android 352 353 #endif // __LIBS_ASSETMANAGER_H 354