/*
* 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 <androidfw/Asset.h>
#include <androidfw/AssetDir.h>
#include <androidfw/ZipFileRO.h>
#include <utils/KeyedVector.h>
#include <utils/SortedVector.h>
#include <utils/String16.h>
#include <utils/String8.h>
#include <utils/threads.h>
#include <utils/Vector.h>
/*
* Native-app access is via the opaque typedef struct AAssetManager in the C namespace.
*/
#ifdef __cplusplus
extern "C" {
#endif
struct AAssetManager { };
#ifdef __cplusplus
};
#endif
/*
* Now the proper C++ android-namespace definitions
*/
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 AAssetManager {
public:
static const char* RESOURCES_FILENAME;
static const char* IDMAP_BIN;
static const char* OVERLAY_DIR;
static const char* TARGET_PACKAGE_NAME;
static const char* TARGET_APK_PATH;
static const char* IDMAP_DIR;
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, the assets are added as shared
* library if appAsLib is true.
*
* 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, int32_t* cookie,
bool appAsLib=false, bool isSystemAsset=false);
bool addOverlayPath(const String8& path, int32_t* 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 0, resulting in the first cookie being returned.
* Each next cookie will be returned there-after, until -1 indicating
* the end has been reached.
*/
int32_t nextAssetPath(const int32_t cookie) const;
/*
* Return an asset path in the manager. 'which' must be between 0 and
* countAssetPaths().
*/
String8 getAssetPath(const int32_t 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);
void getConfiguration(ResTable_config* outConfig) const;
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, int32_t* outCookie = NULL);
/*
* 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(const int32_t 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(const int32_t 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, bool includeSystemLocales=true) const;
/**
* Generate idmap data to translate resources IDs between a package and a
* corresponding overlay package.
*/
bool createIdmap(const char* targetApkPath, const char* overlayApkPath,
uint32_t targetCrc, uint32_t overlayCrc, uint32_t** outData, size_t* outSize);
private:
struct asset_path
{
asset_path() : path(""), type(kFileTypeRegular), idmap(""),
isSystemOverlay(false), isSystemAsset(false) {}
String8 path;
FileType type;
String8 idmap;
bool isSystemOverlay;
bool isSystemAsset;
};
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;
bool appendPathToResTable(const asset_path& ap, bool appAsLib=false) const;
Asset* openIdmapLocked(const struct asset_path& ap) const;
void addSystemOverlays(const char* pathOverlaysList, const String8& targetPackagePath,
ResTable* sharedRes, size_t offset) const;
class SharedZip : public RefBase {
public:
static sp<SharedZip> get(const String8& path, bool createIfNotPresent = true);
ZipFileRO* getZip();
Asset* getResourceTableAsset();
Asset* setResourceTableAsset(Asset* asset);
ResTable* getResourceTable();
ResTable* setResourceTable(ResTable* res);
bool isUpToDate();
void addOverlay(const asset_path& ap);
bool getOverlay(size_t idx, asset_path* out) const;
protected:
~SharedZip();
private:
SharedZip(const String8& path, time_t modWhen);
SharedZip(); // <-- not implemented
String8 mPath;
ZipFileRO* mZipFile;
time_t mModWhen;
Asset* mResourceTableAsset;
ResTable* mResourceTable;
Vector<asset_path> mOverlays;
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();
void addOverlay(const String8& path, const asset_path& overlay);
bool getOverlay(const String8& path, size_t idx, asset_path* out) const;
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