TZIPFile*¶
Describes a ZIP archive file containing multiple sub-files.
Typically the sub-files are ROOT files. Notice that
the ROOT files should not be compressed when being added to the
ZIP file, since ROOT files are normally already compressed.
Such a ZIP file should be created like:
zip -n root multi file1.root file2.root
which creates a ZIP file multi.zip.
A ZIP archive consists of files compressed with the popular ZLIB
compression algorithm. The archive format is used among others by
PKZip and Info-ZIP. The compression algorithm is also used by
GZIP and the PNG graphics standard. The format of the archives is
explained briefly below. This class provides an interface to read
such archives.
A ZIP archive contains a prefix, series of archive members
(sub-files), and a central directory. In theory the archive could
span multiple disks (or files) with the central directory of the
whole archive on the last disk, but this class does not support
such multi-part archives. The prefix is only used in self-extracting
executable archive files.
The members are stored in the archive sequentially, each with a
local header followed by the (optionally) compressed data; the local
header describes the member, including its file name and compressed
and real sizes. The central directory includes the member details
again, plus allows an extra member comment to be added. The last
member in the central directory is an end marker that can contain
a comment for the whole archive. Both the local header and the
central directory can also carry extra member-specific data; the
data in the local and global parts can be different.
The fact that the archive has a global directory makes it efficient
and allows for only the reading of the desired data, one does not
have to scan through the whole file to find the desired sub-file.
The Zip64 extensions are supported so files larger than 2GB can be
stored in archives larger than 4 GB.
Once the archive has been opened, the client can query the members
and read their contents by asking the archive for an offset where
the sub-file starts. The members can be accessed in any order.
class TZIPFile : public TArchiveFile
class TZIPMember : public TArchiveMember
class¶
protected:
Long64_t fDirPos; ///< Central directory position
Long64_t fDirSize; ///< Central directory size
Long64_t fDirOffset; ///< Central directory offset (from the beginning of the archive)
TString fComment; ///< Archive comment
Long64_t FindEndHeader();
/// Find the end header of the ZIP archive. Returns 0 in case of error.
Int_t ReadEndHeader(Long64_t pos);
/// Read the end header of the ZIP archive including the archive comment
/// at the current file position. Check that it really was a single-disk
/// archive with all the entries as expected. Most importantly, figure
/// out where the central directory begins. Returns -1 in case of error,
/// 0 otherwise.
Long64_t ReadZip64EndLocator(Long64_t pos);
/// Read Zip64 end of central directory locator. Returns -1 in case of error,
/// -2 in case end locator magic is not found (i.e. not a zip64 file) and
/// offset of Zip64 end of central directory record in case of success.
Int_t ReadZip64EndRecord(Long64_t pos);
/// Read Zip64 end of central directory record. Returns -1 in case of error
/// and 0 in case of success.
Int_t ReadDirectory();
/// Read the directory of the ZIP archive. Returns -1 in case of error,
/// 0 otherwise.
Int_t ReadMemberHeader(TZIPMember *member);
/// Read the member header of the ZIP archive. Sets the position where
/// the data starts in the member object. Returns -1 in case of error,
/// 0 otherwise.
UInt_t Get(const void *buffer, Int_t bytes);
/// Read a "bytes" long little-endian integer value from "buffer".
ULong64_t Get64(const void *buffer, Int_t bytes);
/// Read a 8 byte long little-endian integer value from "buffer".
Int_t DecodeZip64ExtendedExtraField(TZIPMember *m, Bool_t global = kTRUE);
/// Decode the Zip64 extended extra field. If global is true, decode the
/// extra field coming from the central directory, if false decode the
/// extra field coming from the local file header. Returns -1 in case of
/// error, -2 in case Zip64 extra block was not found and 0 in case of
/// success.
/// ZIP archive constants
enum EZIPConstants {
// - Archive version required (and made)
kARCHIVE_VERSION = 45,
// - Magic header constants
kDIR_HEADER_MAGIC = 0x02014b50,
kENTRY_HEADER_MAGIC = 0x04034b50,
kEND_HEADER_MAGIC = 0x06054b50,
kZIP64_EDR_HEADER_MAGIC = 0x06064b50,
kZIP64_EDL_HEADER_MAGIC = 0x07064b50,
kZIP64_EXTENDED_MAGIC = 0x0001, ///< Zip64 Extended Information Extra Field
kZIP_MAGIC_LEN = 4, ///< Length of magic's
kMAX_VAR_LEN = 0xffff, ///< Max variable-width field length
kMAX_SIZE = 0xffffffff, ///< Max size of things
// - Offsets into the central directory headers
kDIR_MAGIC_OFF = 0,
kDIR_VMADE_OFF = 4, kDIR_VMADE_LEN = 2,
kDIR_VREQD_OFF = 6, kDIR_VREQD_LEN = 2,
kDIR_FLAG_OFF = 8, kDIR_FLAG_LEN = 2,
kDIR_METHOD_OFF = 10, kDIR_METHOD_LEN = 2,
kDIR_DATE_OFF = 12, kDIR_DATE_LEN = 4,
kDIR_CRC32_OFF = 16, kDIR_CRC32_LEN = 4,
kDIR_CSIZE_OFF = 20, kDIR_CSIZE_LEN = 4,
kDIR_USIZE_OFF = 24, kDIR_USIZE_LEN = 4,
kDIR_NAMELEN_OFF = 28, kDIR_NAMELEN_LEN = 2,
kDIR_EXTRALEN_OFF = 30, kDIR_EXTRALEN_LEN = 2,
kDIR_COMMENTLEN_OFF = 32, kDIR_COMMENTLEN_LEN = 2,
kDIR_DISK_START_OFF = 34, kDIR_DISK_START_LEN = 2,
kDIR_INT_ATTR_OFF = 36, kDIR_INT_ATTR_LEN = 2,
kDIR_EXT_ATTR_OFF = 38, kDIR_EXT_ATTR_LEN = 4,
kDIR_ENTRY_POS_OFF = 42, kDIR_ENTRY_POS_LEN = 4,
kDIR_HEADER_SIZE = 46,
// - Offsets into the Zip64 end of central directory record (EDR)
kZIP64_EDR_MAGIC_OFF = 0,
kZIP64_EDR_SIZE_OFF = 4, kZIP64_EDR_SIZE_LEN = 8,
kZIP64_EDR_VERS_MADE_OFF = 12, kZIP64_EDR_VERS_MADE_LEN = 2,
kZIP64_EDR_VERS_EXT_OFF = 14, kZIP64_EDR_VERS_EXT_LEN = 2,
kZIP64_EDR_DISK_OFF = 16, kZIP64_EDR_DISK_LEN = 4,
kZIP64_EDR_DIR_DISK_OFF = 20, kZIP64_EDR_DIR_DISK_LEN = 4,
kZIP64_EDR_DISK_HDRS_OFF = 24, kZIP64_EDR_DISK_HDRS_LEN = 8,
kZIP64_EDR_TOTAL_HDRS_OFF = 32, kZIP64_EDR_TOTAL_HDRS_LEN = 8,
kZIP64_EDR_DIR_SIZE_OFF = 40, kZIP64_EDR_DIR_SIZE_LEN = 8,
kZIP64_EDR_DIR_OFFSET_OFF = 48, kZIP64_EDR_DIR_OFFSET_LEN = 8,
kZIP64_EDR_HEADER_SIZE = 56,
// - Offsets into the Zip64 end of central directory locator (EDL)
kZIP64_EDL_MAGIC_OFF = 0,
kZIP64_EDL_DISK_OFF = 4, kZIP64_EDL_DISK_LEN = 4,
kZIP64_EDL_REC_OFFSET_OFF = 8, kZIP64_EDL_REC_OFFSET_LEN = 8,
kZIP64_EDL_TOTAL_DISK_OFF = 16, kZIP64_EDL_TOTAL_DISK_LEN = 4,
kZIP64_EDL_HEADER_SIZE = 20,
// - Offsets into the end-of-archive header
kEND_MAGIC_OFF = 0,
kEND_DISK_OFF = 4, kEND_DISK_LEN = 2,
kEND_DIR_DISK_OFF = 6, kEND_DIR_DISK_LEN = 2,
kEND_DISK_HDRS_OFF = 8, kEND_DISK_HDRS_LEN = 2,
kEND_TOTAL_HDRS_OFF = 10, kEND_TOTAL_HDRS_LEN = 2,
kEND_DIR_SIZE_OFF = 12, kEND_DIR_SIZE_LEN = 4,
kEND_DIR_OFFSET_OFF = 16, kEND_DIR_OFFSET_LEN = 4,
kEND_COMMENTLEN_OFF = 20, kEND_COMMENTLEN_LEN = 2,
kEND_HEADER_SIZE = 22,
// - Offsets into the local entry headers
kENTRY_MAGIC_OFF = 0,
kENTRY_VREQD_OFF = 4, kENTRY_VREQD_LEN = 2,
kENTRY_FLAG_OFF = 6, kENTRY_FLAG_LEN = 2,
kENTRY_METHOD_OFF = 8, kENTRY_METHOD_LEN = 2,
kENTRY_DATE_OFF = 10, kENTRY_DATE_LEN = 4,
kENTRY_CRC32_OFF = 14, kENTRY_CRC32_LEN = 4,
kENTRY_CSIZE_OFF = 18, kENTRY_CSIZE_LEN = 4,
kENTRY_USIZE_OFF = 22, kENTRY_USIZE_LEN = 4,
kENTRY_NAMELEN_OFF = 26, kENTRY_NAMELEN_LEN = 2,
kENTRY_EXTRALEN_OFF = 28, kENTRY_EXTRALEN_LEN = 2,
kENTRY_HEADER_SIZE = 30,
// - Offsets into the Zip64 Extended Information Extra Field
kZIP64_EXTENDED_MAGIC_OFF = 0, kZIP64_EXTENDED_MAGIC_LEN = 2,
kZIP64_EXTENDED_SIZE_OFF = 2, kZIP64_EXTENDED_SIZE_LEN = 2,
kZIP64_EXTENDED_USIZE_OFF = 4, kZIP64_EXTENDED_USIZE_LEN = 8,
kZIP64_EXTENTED_CSIZE_OFF = 12, kZIP64_EXTENDED_CSIZE_LEN = 8,
kZIP64_EXTENDED_HDR_OFFSET_OFF = 20, kZIP64_EXTENDED_HDR_OFFSET_LEN = 8,
kZIP64_EXTENDED_DISK_OFF = 28, kZIP64_EXTENDED_DISK_LEN = 4,
kZIP64_EXTENDED_SIZE = 32,
// - Compression method and strategy
kSTORED = 0, ///< Stored as is
kDEFLATED = 8 ///< Stored using deflate
};
TZIPFile(const TZIPFile&); // Not implemented
TZIPFile& operator=(const TZIPFile&); // Not implemented
public:
TZIPFile();
TZIPFile(const char *archive, const char *member, TFile *file);
/// Specify the archive name and member name. The member can be a decimal
/// number which allows to access the n-th member.
virtual ~TZIPFile() { }
virtual Int_t OpenArchive();
/// Open archive and read end-header and directory. Returns -1 in case
/// of error, 0 otherwise.
virtual Int_t SetCurrentMember();
/// Find the desired member in the member array and make it the
/// current member. Returns -1 in case member is not found, 0 otherwise.
void Print(Option_t *option = "") const;
/// Pretty print ZIP archive members.
TZIPMember
/**
\class TZIPMember
\ingroup IO
A ZIP archive consists of files compressed with the popular ZLIB
compression algorithm; this class records the information about a
single archive member.
*/
friend class TZIPFile;
private:
void *fLocal; ///< Extra file header data
UInt_t fLocalLen; ///< Length of extra file header data
void *fGlobal; ///< Extra directory data
UInt_t fGlobalLen; ///< Length of extra directory data
UInt_t fCRC32; ///< CRC-32 for all decompressed data
UInt_t fAttrInt; ///< Internal file attributes
UInt_t fAttrExt; ///< External file attributes
UInt_t fMethod; ///< Compression type
UInt_t fLevel; ///< Compression level
public:
TZIPMember();
TZIPMember(const char *name);/// Create ZIP member file.
TZIPMember(const TZIPMember &member);
TZIPMember &operator=(const TZIPMember &rhs);
virtual ~TZIPMember();
void *GetLocal() const { return fLocal; }
UInt_t GetLocalLen() const { return fLocalLen; }
void *GetGlobal() const { return fGlobal; }
UInt_t GetGlobalLen() const { return fGlobalLen; }
UInt_t GetCRC32() const { return fCRC32; }
UInt_t GetAttrInt() const { return fAttrInt; }
UInt_t GetAttrExt() const { return fAttrExt; }
UInt_t GetMethod() const { return fMethod; }
UInt_t GetLevel() const { return fLevel; }
void Print(Option_t *option = "") const;
/// Pretty print basic ZIP member info.