diff options
Diffstat (limited to 'include/androidfw/ZipFileRO.h')
| -rw-r--r-- | include/androidfw/ZipFileRO.h | 172 |
1 files changed, 40 insertions, 132 deletions
diff --git a/include/androidfw/ZipFileRO.h b/include/androidfw/ZipFileRO.h index 547e36a09864..ad5be1232e67 100644 --- a/include/androidfw/ZipFileRO.h +++ b/include/androidfw/ZipFileRO.h @@ -40,6 +40,8 @@ #include <unistd.h> #include <time.h> +typedef void* ZipArchiveHandle; + namespace android { /* @@ -51,18 +53,13 @@ typedef void* ZipEntryRO; /* * Open a Zip archive for reading. * - * We want "open" and "find entry by name" to be fast operations, and we - * want to use as little memory as possible. We memory-map the file, - * and load a hash table with pointers to the filenames (which aren't - * null-terminated). The other fields are at a fixed offset from the - * filename, so we don't need to extract those (but we do need to byte-read - * and endian-swap them every time we want them). + * Implemented as a thin wrapper over system/core/libziparchive. + * + * "open" and "find entry by name" are fast operations and use as little + * memory as possible. * - * To speed comparisons when doing a lookup by name, we could make the mapping - * "private" (copy-on-write) and null-terminate the filenames after verifying - * the record structure. However, this requires a private mapping of - * every page that the Central Directory touches. Easier to tuck a copy - * of the string length into the hash table entry. + * We also support fast iteration over all entries in the file (with a + * stable, but unspecified iteration order). * * NOTE: If this is used on file descriptors inherited from a fork() operation, * you must be on a platform that implements pread() to guarantee correctness @@ -70,48 +67,44 @@ typedef void* ZipEntryRO; */ class ZipFileRO { public: - ZipFileRO() - : mFd(-1), mFileName(NULL), mFileLength(-1), - mDirectoryMap(NULL), - mNumEntries(-1), mDirectoryOffset(-1), - mHashTableSize(-1), mHashTable(NULL) - {} - - ~ZipFileRO(); + /* Zip compression methods we support */ + enum { + kCompressStored = 0, // no compression + kCompressDeflated = 8, // standard deflate + }; /* * Open an archive. */ - status_t open(const char* zipFileName); + static ZipFileRO* open(const char* zipFileName); /* * Find an entry, by name. Returns the entry identifier, or NULL if * not found. - * - * If two entries have the same name, one will be chosen at semi-random. */ - ZipEntryRO findEntryByName(const char* fileName) const; + ZipEntryRO findEntryByName(const char* entryName) const; + /* - * Return the #of entries in the Zip archive. + * Start iterating over the list of entries in the zip file. Requires + * a matching call to endIteration with the same cookie. */ - int getNumEntries(void) const { - return mNumEntries; - } + bool startIteration(void** cookie); + + /** + * Return the next entry in iteration order, or NULL if there are no more + * entries in this archive. + */ + ZipEntryRO nextEntry(void* cookie); + + void endIteration(void* cookie); + + void releaseEntry(ZipEntryRO entry) const; /* - * Return the Nth entry. Zip file entries are not stored in sorted - * order, and updated entries may appear at the end, so anyone walking - * the archive needs to avoid making ordering assumptions. We take - * that further by returning the Nth non-empty entry in the hash table - * rather than the Nth entry in the archive. - * - * Valid values are [0..numEntries). - * - * [This is currently O(n). If it needs to be fast we can allocate an - * additional data structure or provide an iterator interface.] + * Return the #of entries in the Zip archive. */ - ZipEntryRO findEntryByIndex(int idx) const; + int getNumEntries(); /* * Copy the filename into the supplied buffer. Returns 0 on success, @@ -149,112 +142,27 @@ public: * * Returns "true" on success. */ - bool uncompressEntry(ZipEntryRO entry, void* buffer) const; + bool uncompressEntry(ZipEntryRO entry, void* buffer, size_t size) const; /* * Uncompress the data to an open file descriptor. */ bool uncompressEntry(ZipEntryRO entry, int fd) const; - /* Zip compression methods we support */ - enum { - kCompressStored = 0, // no compression - kCompressDeflated = 8, // standard deflate - }; - - /* - * Utility function: uncompress deflated data, buffer to buffer. - */ - static bool inflateBuffer(void* outBuf, const void* inBuf, - size_t uncompLen, size_t compLen); - - /* - * Utility function: uncompress deflated data, buffer to fd. - */ - static bool inflateBuffer(int fd, const void* inBuf, - size_t uncompLen, size_t compLen); - - /* - * Utility function to convert ZIP's time format to a timespec struct. - */ - static inline void zipTimeToTimespec(long when, struct tm* timespec) { - const long date = when >> 16; - timespec->tm_year = ((date >> 9) & 0x7F) + 80; // Zip is years since 1980 - timespec->tm_mon = (date >> 5) & 0x0F; - timespec->tm_mday = date & 0x1F; - - timespec->tm_hour = (when >> 11) & 0x1F; - timespec->tm_min = (when >> 5) & 0x3F; - timespec->tm_sec = (when & 0x1F) << 1; - } - - /* - * Some basic functions for raw data manipulation. "LE" means - * Little Endian. - */ - static inline unsigned short get2LE(const unsigned char* buf) { - return buf[0] | (buf[1] << 8); - } - static inline unsigned long get4LE(const unsigned char* buf) { - return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24); - } + ~ZipFileRO(); private: - /* these are private and not defined */ + /* these are private and not defined */ ZipFileRO(const ZipFileRO& src); ZipFileRO& operator=(const ZipFileRO& src); - /* locate and parse the central directory */ - bool mapCentralDirectory(void); - - /* parse the archive, prepping internal structures */ - bool parseZipArchive(void); - - /* add a new entry to the hash table */ - void addToHash(const char* str, int strLen, unsigned int hash); - - /* compute string hash code */ - static unsigned int computeHash(const char* str, int len); - - /* convert a ZipEntryRO back to a hash table index */ - int entryToIndex(const ZipEntryRO entry) const; - - /* - * One entry in the hash table. - */ - typedef struct HashEntry { - const char* name; - unsigned short nameLen; - //unsigned int hash; - } HashEntry; - - /* open Zip archive */ - int mFd; - - /* Lock for handling the file descriptor (seeks, etc) */ - mutable Mutex mFdLock; - - /* zip file name */ - char* mFileName; - - /* length of file */ - size_t mFileLength; - - /* mapped file */ - FileMap* mDirectoryMap; - - /* number of entries in the Zip archive */ - int mNumEntries; - - /* CD directory offset in the Zip archive */ - off64_t mDirectoryOffset; + ZipFileRO(ZipArchiveHandle handle, char* fileName) : mHandle(handle), + mFileName(fileName) + { + } - /* - * We know how many entries are in the Zip archive, so we have a - * fixed-size hash table. We probe for an empty slot. - */ - int mHashTableSize; - HashEntry* mHashTable; + const ZipArchiveHandle mHandle; + char* mFileName; }; }; // namespace android |