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Diffstat (limited to 'modules/libjar/nsZipArchive.h')
-rw-r--r-- | modules/libjar/nsZipArchive.h | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/modules/libjar/nsZipArchive.h b/modules/libjar/nsZipArchive.h new file mode 100644 index 0000000000..e38445ea87 --- /dev/null +++ b/modules/libjar/nsZipArchive.h @@ -0,0 +1,401 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef nsZipArchive_h_ +#define nsZipArchive_h_ + +#include "mozilla/Attributes.h" + +#define ZIP_TABSIZE 256 +#define ZIP_BUFLEN \ + (4 * 1024) /* Used as output buffer when deflating items to a file */ + +#include "zlib.h" +#include "zipstruct.h" +#include "nsIFile.h" +#include "nsISupportsImpl.h" // For mozilla::ThreadSafeAutoRefCnt +#include "mozilla/ArenaAllocator.h" +#include "mozilla/FileUtils.h" +#include "mozilla/FileLocation.h" +#include "mozilla/Mutex.h" +#include "mozilla/UniquePtr.h" + +class nsZipFind; +struct PRFileDesc; + +/** + * This file defines some of the basic structures used by libjar to + * read Zip files. It makes use of zlib in order to do the decompression. + * + * A few notes on the classes/structs: + * nsZipArchive represents a single Zip file, and maintains an index + * of all the items in the file. + * nsZipItem represents a single item (file) in the Zip archive. + * nsZipFind represents the metadata involved in doing a search, + * and current state of the iteration of found objects. + * 'MT''safe' reading from the zipfile is performed through JARInputStream, + * which maintains its own file descriptor, allowing for multiple reads + * concurrently from the same zip file. + * + * nsZipArchives are accessed from multiple threads. + */ + +/** + * nsZipItem -- a helper struct for nsZipArchive + * + * each nsZipItem represents one file in the archive and all the + * information needed to manipulate it. + */ +class nsZipItem final { + public: + nsZipItem(); + + const char* Name() { return ((const char*)central) + ZIPCENTRAL_SIZE; } + + uint32_t LocalOffset(); + uint32_t Size(); + uint32_t RealSize(); + uint32_t CRC32(); + uint16_t Date(); + uint16_t Time(); + uint16_t Compression(); + bool IsDirectory(); + uint16_t Mode(); + const uint8_t* GetExtraField(uint16_t aTag, uint16_t* aBlockSize); + PRTime LastModTime(); + + nsZipItem* next; + const ZipCentral* central; + uint16_t nameLength; + bool isSynthetic; +}; + +class nsZipHandle; + +/** + * nsZipArchive -- a class for reading the PKZIP file format. + * + */ +class nsZipArchive final { + friend class nsZipFind; + + /** destructing the object closes the archive */ + ~nsZipArchive(); + + public: + static const char* sFileCorruptedReason; + + /** + * OpenArchive + * + * @param aZipHandle The nsZipHandle used to access the zip + * @param aFd Optional PRFileDesc for Windows readahead optimization + * @return status code + */ + static already_AddRefed<nsZipArchive> OpenArchive(nsZipHandle* aZipHandle, + PRFileDesc* aFd = nullptr); + + /** + * OpenArchive + * + * Convenience function that generates nsZipHandle + * + * @param aFile The file used to access the zip + * @return status code + */ + static already_AddRefed<nsZipArchive> OpenArchive(nsIFile* aFile); + + /** + * Test the integrity of items in this archive by running + * a CRC check after extracting each item into a memory + * buffer. If an entry name is supplied only the + * specified item is tested. Else, if null is supplied + * then all the items in the archive are tested. + * + * @return status code + */ + nsresult Test(const char* aEntryName); + + /** + * GetItem + * @param aEntryName Name of file in the archive + * @return pointer to nsZipItem + */ + nsZipItem* GetItem(const char* aEntryName); + + /** + * ExtractFile + * + * @param zipEntry Name of file in archive to extract + * @param outFD Filedescriptor to write contents to + * @param outname Name of file to write to + * @return status code + */ + nsresult ExtractFile(nsZipItem* zipEntry, nsIFile* outFile, + PRFileDesc* outFD); + + /** + * FindInit + * + * Initializes a search for files in the archive. FindNext() returns + * the actual matches. The nsZipFind must be deleted when you're done + * + * @param aPattern a string or RegExp pattern to search for + * (may be nullptr to find all files in archive) + * @param aFind a pointer to a pointer to a structure used + * in FindNext. In the case of an error this + * will be set to nullptr. + * @return status code + */ + nsresult FindInit(const char* aPattern, nsZipFind** aFind); + + /* + * Gets an undependent handle to the mapped file. + */ + nsZipHandle* GetFD() const; + + /** + * Gets the data offset. + * @param aItem Pointer to nsZipItem + * returns 0 on failure. + */ + uint32_t GetDataOffset(nsZipItem* aItem); + + /** + * Get pointer to the data of the item. + * @param aItem Pointer to nsZipItem + * reutrns null when zip file is corrupt. + */ + const uint8_t* GetData(nsZipItem* aItem); + + /** + * Gets the amount of memory taken up by the archive's mapping. + * @return the size + */ + int64_t SizeOfMapping(); + + /* + * Refcounting + */ + NS_METHOD_(MozExternalRefCountType) AddRef(void); + NS_METHOD_(MozExternalRefCountType) Release(void); + + private: + nsZipArchive(nsZipHandle* aZipHandle, PRFileDesc* aFd, nsresult& aRv); + + //--- private members --- + mozilla::ThreadSafeAutoRefCnt mRefCnt; /* ref count */ + NS_DECL_OWNINGTHREAD + + // These fields are all effectively const after the constructor + // file handle + const RefPtr<nsZipHandle> mFd; + // file URI, for logging + nsCString mURI; + // Is true if we use zipLog to log accesses in jar/zip archives. This helper + // variable avoids grabbing zipLog's lock when not necessary. + // Effectively const after constructor + bool mUseZipLog; + + mozilla::Mutex mLock{"nsZipArchive"}; + // all of the following members are guarded by mLock: + nsZipItem* mFiles[ZIP_TABSIZE] MOZ_GUARDED_BY(mLock); + mozilla::ArenaAllocator<1024, sizeof(void*)> mArena MOZ_GUARDED_BY(mLock); + // Whether we synthesized the directory entries + bool mBuiltSynthetics MOZ_GUARDED_BY(mLock); + + private: + //--- private methods --- + nsZipItem* CreateZipItem() MOZ_REQUIRES(mLock); + nsresult BuildFileList(PRFileDesc* aFd = nullptr); + nsresult BuildSynthetics(); + + nsZipArchive& operator=(const nsZipArchive& rhs) = delete; + nsZipArchive(const nsZipArchive& rhs) = delete; +}; + +/** + * nsZipFind + * + * a helper class for nsZipArchive, representing a search + */ +class nsZipFind final { + public: + nsZipFind(nsZipArchive* aZip, char* aPattern, bool regExp); + ~nsZipFind(); + + nsresult FindNext(const char** aResult, uint16_t* aNameLen); + + private: + RefPtr<nsZipArchive> mArchive; + char* mPattern; + nsZipItem* mItem; + uint16_t mSlot; + bool mRegExp; + + nsZipFind& operator=(const nsZipFind& rhs) = delete; + nsZipFind(const nsZipFind& rhs) = delete; +}; + +/** + * nsZipCursor -- a low-level class for reading the individual items in a zip. + */ +class nsZipCursor final { + public: + /** + * Initializes the cursor + * + * @param aItem Item of interest + * @param aZip Archive + * @param aBuf Buffer used for decompression. + * This determines the maximum Read() size in the + * compressed case. + * @param aBufSize Buffer size + * @param doCRC When set to true Read() will check crc + */ + nsZipCursor(nsZipItem* aItem, nsZipArchive* aZip, uint8_t* aBuf = nullptr, + uint32_t aBufSize = 0, bool doCRC = false); + + ~nsZipCursor(); + + /** + * Performs reads. In the compressed case it uses aBuf(passed in constructor), + * for stored files it returns a zero-copy buffer. + * + * @param aBytesRead Outparam for number of bytes read. + * @return data read or nullptr if item is corrupted. + */ + uint8_t* Read(uint32_t* aBytesRead) { return ReadOrCopy(aBytesRead, false); } + + /** + * Performs a copy. It always uses aBuf(passed in constructor). + * + * @param aBytesRead Outparam for number of bytes read. + * @return data read or nullptr if item is corrupted. + */ + uint8_t* Copy(uint32_t* aBytesRead) { return ReadOrCopy(aBytesRead, true); } + + private: + /* Actual implementation for both Read and Copy above */ + uint8_t* ReadOrCopy(uint32_t* aBytesRead, bool aCopy); + + nsZipItem* mItem; + uint8_t* mBuf; + uint32_t mBufSize; + z_stream mZs; + uint32_t mCRC; + bool mDoCRC; +}; + +/** + * nsZipItemPtr - a RAII convenience class for reading the individual items in a + * zip. It reads whole files and does zero-copy IO for stored files. A buffer is + * allocated for decompression. Do not use when the file may be very large. + */ +class nsZipItemPtr_base { + public: + /** + * Initializes the reader + * + * @param aZip Archive + * @param aEntryName Archive membername + * @param doCRC When set to true Read() will check crc + */ + nsZipItemPtr_base(nsZipArchive* aZip, const char* aEntryName, bool doCRC); + + uint32_t Length() const { return mReadlen; } + + protected: + RefPtr<nsZipHandle> mZipHandle; + mozilla::UniquePtr<uint8_t[]> mAutoBuf; + uint8_t* mReturnBuf; + uint32_t mReadlen; +}; + +template <class T> +class nsZipItemPtr final : public nsZipItemPtr_base { + static_assert(sizeof(T) == sizeof(char), + "This class cannot be used with larger T without re-examining" + " a number of assumptions."); + + public: + nsZipItemPtr(nsZipArchive* aZip, const char* aEntryName, bool doCRC = false) + : nsZipItemPtr_base(aZip, aEntryName, doCRC) {} + /** + * @return buffer containing the whole zip member or nullptr on error. + * The returned buffer is owned by nsZipItemReader. + */ + const T* Buffer() const { return (const T*)mReturnBuf; } + + operator const T*() const { return Buffer(); } + + /** + * Relinquish ownership of zip member if compressed. + * Copy member into a new buffer if uncompressed. + * @return a buffer with whole zip member. It is caller's responsibility to + * free() it. + */ + mozilla::UniquePtr<T[]> Forget() { + if (!mReturnBuf) return nullptr; + // In uncompressed mmap case, give up buffer + if (mAutoBuf.get() == mReturnBuf) { + mReturnBuf = nullptr; + return mozilla::UniquePtr<T[]>(reinterpret_cast<T*>(mAutoBuf.release())); + } + auto ret = mozilla::MakeUnique<T[]>(Length()); + memcpy(ret.get(), mReturnBuf, Length()); + mReturnBuf = nullptr; + return ret; + } +}; + +class nsZipHandle final { + friend class nsZipArchive; + friend class nsZipFind; + friend class mozilla::FileLocation; + friend class nsJARInputStream; +#if defined(XP_UNIX) && !defined(XP_DARWIN) + friend class MmapAccessScope; +#endif + + public: + static nsresult Init(nsIFile* file, nsZipHandle** ret, + PRFileDesc** aFd = nullptr); + static nsresult Init(nsZipArchive* zip, const char* entry, nsZipHandle** ret); + + NS_METHOD_(MozExternalRefCountType) AddRef(void); + NS_METHOD_(MozExternalRefCountType) Release(void); + + int64_t SizeOfMapping(); + + nsresult GetNSPRFileDesc(PRFileDesc** aNSPRFileDesc); + + protected: + const uint8_t* mFileData; /* pointer to zip data */ + uint32_t mLen; /* length of zip data */ + mozilla::FileLocation mFile; /* source file if any, for logging */ + + private: + nsZipHandle(); + ~nsZipHandle(); + + nsresult findDataStart(); + + PRFileMap* mMap; /* nspr datastructure for mmap */ + mozilla::AutoFDClose mNSPRFileDesc; + mozilla::UniquePtr<nsZipItemPtr<uint8_t> > mBuf; + mozilla::ThreadSafeAutoRefCnt mRefCnt; /* ref count */ + NS_DECL_OWNINGTHREAD + + const uint8_t* mFileStart; /* pointer to mmaped file */ + uint32_t mTotalLen; /* total length of the mmaped file */ + + /* Magic number for CRX type expressed in Big Endian since it is a literal */ + static const uint32_t kCRXMagic = 0x34327243; +}; + +nsresult gZlibInit(z_stream* zs); + +#endif /* nsZipArchive_h_ */ |