/* * Copyright (C) 2006 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. */ // // Asset management class. AssetManager objects are thread-safe. // #ifndef __LIBS_ASSETMANAGER_H #define __LIBS_ASSETMANAGER_H #include <utils/Asset.h> #include <utils/AssetDir.h> #include <utils/KeyedVector.h> #include <utils/String8.h> #include <utils/Vector.h> #include <utils/String16.h> #include <utils/ZipFileRO.h> #include <utils/threads.h> namespace android { class Asset; // fwd decl for things that include Asset.h first class ResTable; struct ResTable_config; /* * Every application that uses assets needs one instance of this. A * single instance may be shared across multiple threads, and a single * thread may have more than one instance (the latter is discouraged). * * The purpose of the AssetManager is to create Asset objects. To do * this efficiently it may cache information about the locations of * files it has seen. This can be controlled with the "cacheMode" * argument. * * The asset hierarchy may be examined like a filesystem, using * AssetDir objects to peruse a single directory. */ class AssetManager { public: typedef enum CacheMode { CACHE_UNKNOWN = 0, CACHE_OFF, // don't try to cache file locations CACHE_DEFER, // construct cache as pieces are needed //CACHE_SCAN, // scan full(!) asset hierarchy at init() time } CacheMode; AssetManager(CacheMode cacheMode = CACHE_OFF); virtual ~AssetManager(void); static int32_t getGlobalCount(); /* * Add a new source for assets. This can be called multiple times to * look in multiple places for assets. It can be either a directory (for * finding assets as raw files on the disk) or a ZIP file. This newly * added asset path will be examined first when searching for assets, * before any that were previously added. * * Returns "true" on success, "false" on failure. If 'cookie' is non-NULL, * then on success, *cookie is set to the value corresponding to the * newly-added asset source. */ bool addAssetPath(const String8& path, void** cookie); /* * Convenience for adding the standard system assets. Uses the * ANDROID_ROOT environment variable to find them. */ bool addDefaultAssets(); /* * Iterate over the asset paths in this manager. (Previously * added via addAssetPath() and addDefaultAssets().) On first call, * 'cookie' must be NULL, resulting in the first cookie being returned. * Each next cookie will be returned there-after, until NULL indicating * the end has been reached. */ void* nextAssetPath(void* cookie) const; /* * Return an asset path in the manager. 'which' must be between 0 and * countAssetPaths(). */ String8 getAssetPath(void* cookie) const; /* * Set the current locale and vendor. The locale can change during * the lifetime of an AssetManager if the user updates the device's * language setting. The vendor is less likely to change. * * Pass in NULL to indicate no preference. */ void setLocale(const char* locale); void setVendor(const char* vendor); /* * Choose screen orientation for resources values returned. */ void setConfiguration(const ResTable_config& config, const char* locale = NULL); typedef Asset::AccessMode AccessMode; // typing shortcut /* * Open an asset. * * This will search through locale-specific and vendor-specific * directories and packages to find the file. * * The object returned does not depend on the AssetManager. It should * be freed by calling Asset::close(). */ Asset* open(const char* fileName, AccessMode mode); /* * Open a non-asset file as an asset. * * This is for opening files that are included in an asset package * but aren't assets. These sit outside the usual "locale/vendor" * path hierarchy, and will not be seen by "AssetDir" or included * in our filename cache. */ Asset* openNonAsset(const char* fileName, AccessMode mode); /* * Explicit non-asset file. The file explicitly named by the cookie (the * resource set to look in) and fileName will be opened and returned. */ Asset* openNonAsset(void* cookie, const char* fileName, AccessMode mode); /* * Open a directory within the asset hierarchy. * * The contents of the directory are an amalgam of vendor-specific, * locale-specific, and generic assets stored loosely or in asset * packages. Depending on the cache setting and previous accesses, * this call may incur significant disk overhead. * * To open the top-level directory, pass in "". */ AssetDir* openDir(const char* dirName); /* * Open a directory within a particular path of the asset manager. * * The contents of the directory are an amalgam of vendor-specific, * locale-specific, and generic assets stored loosely or in asset * packages. Depending on the cache setting and previous accesses, * this call may incur significant disk overhead. * * To open the top-level directory, pass in "". */ AssetDir* openNonAssetDir(void* cookie, const char* dirName); /* * Get the type of a file in the asset hierarchy. They will either * be "regular" or "directory". [Currently only works for "regular".] * * Can also be used as a quick test for existence of a file. */ FileType getFileType(const char* fileName); /* * Return the complete resource table to find things in the package. */ const ResTable& getResources(bool required = true) const; /* * Discard cached filename information. This only needs to be called * if somebody has updated the set of "loose" files, and we want to * discard our cached notion of what's where. */ void purge(void) { purgeFileNameCacheLocked(); } /* * Return true if the files this AssetManager references are all * up-to-date (have not been changed since it was created). If false * is returned, you will need to create a new AssetManager to get * the current data. */ bool isUpToDate(); /** * Get the known locales for this asset manager object. */ void getLocales(Vector<String8>* locales) const; private: struct asset_path { String8 path; FileType type; }; Asset* openInPathLocked(const char* fileName, AccessMode mode, const asset_path& path); Asset* openNonAssetInPathLocked(const char* fileName, AccessMode mode, const asset_path& path); Asset* openInLocaleVendorLocked(const char* fileName, AccessMode mode, const asset_path& path, const char* locale, const char* vendor); String8 createPathNameLocked(const asset_path& path, const char* locale, const char* vendor); String8 createPathNameLocked(const asset_path& path, const char* rootDir); String8 createZipSourceNameLocked(const String8& zipFileName, const String8& dirName, const String8& fileName); ZipFileRO* getZipFileLocked(const asset_path& path); Asset* openAssetFromFileLocked(const String8& fileName, AccessMode mode); Asset* openAssetFromZipLocked(const ZipFileRO* pZipFile, const ZipEntryRO entry, AccessMode mode, const String8& entryName); bool scanAndMergeDirLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, const asset_path& path, const char* rootDir, const char* dirName); SortedVector<AssetDir::FileInfo>* scanDirLocked(const String8& path); bool scanAndMergeZipLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, const asset_path& path, const char* rootDir, const char* dirName); void mergeInfoLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, const SortedVector<AssetDir::FileInfo>* pContents); void loadFileNameCacheLocked(void); void fncScanLocked(SortedVector<AssetDir::FileInfo>* pMergedInfo, const char* dirName); bool fncScanAndMergeDirLocked( SortedVector<AssetDir::FileInfo>* pMergedInfo, const asset_path& path, const char* locale, const char* vendor, const char* dirName); void purgeFileNameCacheLocked(void); const ResTable* getResTable(bool required = true) const; void setLocaleLocked(const char* locale); void updateResourceParamsLocked() const; class SharedZip : public RefBase { public: static sp<SharedZip> get(const String8& path); ZipFileRO* getZip(); Asset* getResourceTableAsset(); Asset* setResourceTableAsset(Asset* asset); ResTable* getResourceTable(); ResTable* setResourceTable(ResTable* res); bool isUpToDate(); protected: ~SharedZip(); private: SharedZip(const String8& path, time_t modWhen); SharedZip(); // <-- not implemented String8 mPath; ZipFileRO* mZipFile; time_t mModWhen; Asset* mResourceTableAsset; ResTable* mResourceTable; static Mutex gLock; static DefaultKeyedVector<String8, wp<SharedZip> > gOpen; }; /* * Manage a set of Zip files. For each file we need a pointer to the * ZipFile and a time_t with the file's modification date. * * We currently only have two zip files (current app, "common" app). * (This was originally written for 8, based on app/locale/vendor.) */ class ZipSet { public: ZipSet(void); ~ZipSet(void); /* * Return a ZipFileRO structure for a ZipFileRO with the specified * parameters. */ ZipFileRO* getZip(const String8& path); Asset* getZipResourceTableAsset(const String8& path); Asset* setZipResourceTableAsset(const String8& path, Asset* asset); ResTable* getZipResourceTable(const String8& path); ResTable* setZipResourceTable(const String8& path, ResTable* res); // generate path, e.g. "common/en-US-noogle.zip" static String8 getPathName(const char* path); bool isUpToDate(); private: void closeZip(int idx); int getIndex(const String8& zip) const; mutable Vector<String8> mZipPath; mutable Vector<sp<SharedZip> > mZipFile; }; // Protect all internal state. mutable Mutex mLock; ZipSet mZipSet; Vector<asset_path> mAssetPaths; char* mLocale; char* mVendor; mutable ResTable* mResources; ResTable_config* mConfig; /* * Cached data for "loose" files. This lets us avoid poking at the * filesystem when searching for loose assets. Each entry is the * "extended partial" path, e.g. "default/default/foo/bar.txt". The * full set of files is present, including ".EXCLUDE" entries. * * We do not cache directory names. We don't retain the ".gz", * because to our clients "foo" and "foo.gz" both look like "foo". */ CacheMode mCacheMode; // is the cache enabled? bool mCacheValid; // clear when locale or vendor changes SortedVector<AssetDir::FileInfo> mCache; }; }; // namespace android #endif // __LIBS_ASSETMANAGER_H