1 package IO::Compress::Gzip::Constants;
9 our ($VERSION, @ISA, @EXPORT, %GZIP_OS_Names);
10 our ($GZIP_FNAME_INVALID_CHAR_RE, $GZIP_FCOMMENT_INVALID_CHAR_RE);
37 GZIP_FEXTRA_HEADER_SIZE
39 GZIP_FEXTRA_SUBFIELD_HEADER_SIZE
40 GZIP_FEXTRA_SUBFIELD_ID_SIZE
41 GZIP_FEXTRA_SUBFIELD_LEN_SIZE
42 GZIP_FEXTRA_SUBFIELD_MAX_SIZE
44 $GZIP_FNAME_INVALID_CHAR_RE
45 $GZIP_FCOMMENT_INVALID_CHAR_RE
63 # Constant names derived from RFC 1952
65 use constant GZIP_ID_SIZE => 2 ;
66 use constant GZIP_ID1 => 0x1F;
67 use constant GZIP_ID2 => 0x8B;
69 use constant GZIP_MIN_HEADER_SIZE => 10 ;# minimum gzip header size
70 use constant GZIP_TRAILER_SIZE => 8 ;
73 use constant GZIP_FLG_DEFAULT => 0x00 ;
74 use constant GZIP_FLG_FTEXT => 0x01 ;
75 use constant GZIP_FLG_FHCRC => 0x02 ; # called CONTINUATION in gzip
76 use constant GZIP_FLG_FEXTRA => 0x04 ;
77 use constant GZIP_FLG_FNAME => 0x08 ;
78 use constant GZIP_FLG_FCOMMENT => 0x10 ;
79 #use constant GZIP_FLG_ENCRYPTED => 0x20 ; # documented in gzip sources
80 use constant GZIP_FLG_RESERVED => (0x20 | 0x40 | 0x80) ;
82 use constant GZIP_XFL_DEFAULT => 0x00 ;
84 use constant GZIP_MTIME_DEFAULT => 0x00 ;
86 use constant GZIP_FEXTRA_HEADER_SIZE => 2 ;
87 use constant GZIP_FEXTRA_MAX_SIZE => 0xFF ;
88 use constant GZIP_FEXTRA_SUBFIELD_ID_SIZE => 2 ;
89 use constant GZIP_FEXTRA_SUBFIELD_LEN_SIZE => 2 ;
90 use constant GZIP_FEXTRA_SUBFIELD_HEADER_SIZE => GZIP_FEXTRA_SUBFIELD_ID_SIZE +
91 GZIP_FEXTRA_SUBFIELD_LEN_SIZE;
92 use constant GZIP_FEXTRA_SUBFIELD_MAX_SIZE => GZIP_FEXTRA_MAX_SIZE -
93 GZIP_FEXTRA_SUBFIELD_HEADER_SIZE ;
99 $GZIP_FNAME_INVALID_CHAR_RE = '[\x00-\x3f\xff]';
100 $GZIP_FCOMMENT_INVALID_CHAR_RE = '[\x00-\x0a\x11-\x14\x16-\x3f\xff]';
105 $GZIP_FNAME_INVALID_CHAR_RE = '[\x00-\x1F\x7F-\x9F]';
106 $GZIP_FCOMMENT_INVALID_CHAR_RE = '[\x00-\x09\x11-\x1F\x7F-\x9F]';
109 use constant GZIP_FHCRC_SIZE => 2 ; # aka CONTINUATION in gzip
111 use constant GZIP_CM_DEFLATED => 8 ;
113 use constant GZIP_NULL_BYTE => "\x00";
114 use constant GZIP_ISIZE_MAX => 0xFFFFFFFF ;
115 use constant GZIP_ISIZE_MOD_VALUE => GZIP_ISIZE_MAX + 1 ;
117 # OS Names sourced from http://www.gzip.org/format.txt
119 use constant GZIP_OS_DEFAULT=> 0xFF ;
127 6 => 'HPFS (OS/2, NT)',
134 13 => 'Acorn RISCOS',
135 14 => 'VFAT file system (Win95, NT)',
140 GZIP_OS_DEFAULT() => 'Unknown',
143 use constant GZIP_MINIMUM_HEADER => pack("C4 V C C",
144 GZIP_ID1, GZIP_ID2, GZIP_CM_DEFLATED, GZIP_FLG_DEFAULT,
145 GZIP_MTIME_DEFAULT, GZIP_XFL_DEFAULT, GZIP_OS_DEFAULT) ;