compress 6.3 KB

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  1. #------------------------------------------------------------------------------
  2. # compress: file(1) magic for pure-compression formats (no archives)
  3. #
  4. # compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, etc.
  5. #
  6. # Formats for various forms of compressed data
  7. # Formats for "compress" proper have been moved into "compress.c",
  8. # because it tries to uncompress it to figure out what's inside.
  9. # standard unix compress
  10. 0 string \037\235 compress'd data
  11. >2 byte&0x80 >0 block compressed
  12. >2 byte&0x1f x %d bits
  13. # gzip (GNU zip, not to be confused with Info-ZIP or PKWARE zip archiver)
  14. # Edited by Chris Chittleborough <cchittleborough@yahoo.com.au>, March 2002
  15. # * Original filename is only at offset 10 if "extra field" absent
  16. # * Produce shorter output - notably, only report compression methods
  17. # other than 8 ("deflate", the only method defined in RFC 1952).
  18. 0 string \037\213 gzip compressed data
  19. >2 byte <8 \b, reserved method
  20. >2 byte >8 \b, unknown method
  21. >3 byte &0x01 \b, ASCII
  22. >3 byte &0x02 \b, has CRC
  23. >3 byte &0x04 \b, extra field
  24. >3 byte&0xC =0x08
  25. >>10 string x \b, was "%s"
  26. >3 byte &0x10 \b, has comment
  27. >9 byte =0x00 \b, from FAT filesystem (MS-DOS, OS/2, NT)
  28. >9 byte =0x01 \b, from Amiga
  29. >9 byte =0x02 \b, from VMS
  30. >9 byte =0x03 \b, from Unix
  31. >9 byte =0x04 \b, from VM/CMS
  32. >9 byte =0x05 \b, from Atari
  33. >9 byte =0x06 \b, from HPFS filesystem (OS/2, NT)
  34. >9 byte =0x07 \b, from MacOS
  35. >9 byte =0x08 \b, from Z-System
  36. >9 byte =0x09 \b, from CP/M
  37. >9 byte =0x0A \b, from TOPS/20
  38. >9 byte =0x0B \b, from NTFS filesystem (NT)
  39. >9 byte =0x0C \b, from QDOS
  40. >9 byte =0x0D \b, from Acorn RISCOS
  41. >3 byte &0x10 \b, comment
  42. >3 byte &0x20 \b, encrypted
  43. >4 ledate >0 \b, last modified: %s
  44. >8 byte 2 \b, max compression
  45. >8 byte 4 \b, max speed
  46. # packed data, Huffman (minimum redundancy) codes on a byte-by-byte basis
  47. 0 string \037\036 packed data
  48. >2 belong >1 \b, %d characters originally
  49. >2 belong =1 \b, %d character originally
  50. #
  51. # This magic number is byte-order-independent.
  52. 0 short 0x1f1f old packed data
  53. # XXX - why *two* entries for "compacted data", one of which is
  54. # byte-order independent, and one of which is byte-order dependent?
  55. #
  56. 0 short 0x1fff compacted data
  57. # This string is valid for SunOS (BE) and a matching "short" is listed
  58. # in the Ultrix (LE) magic file.
  59. 0 string \377\037 compacted data
  60. 0 short 0145405 huf output
  61. # bzip2
  62. 0 string BZh bzip2 compressed data
  63. >3 byte >47 \b, block size = %c00k
  64. # squeeze and crunch
  65. # Michael Haardt <michael@cantor.informatik.rwth-aachen.de>
  66. 0 beshort 0x76FF squeezed data,
  67. >4 string x original name %s
  68. 0 beshort 0x76FE crunched data,
  69. >2 string x original name %s
  70. 0 beshort 0x76FD LZH compressed data,
  71. >2 string x original name %s
  72. # Freeze
  73. 0 string \037\237 frozen file 2.1
  74. 0 string \037\236 frozen file 1.0 (or gzip 0.5)
  75. # SCO compress -H (LZH)
  76. 0 string \037\240 SCO compress -H (LZH) data
  77. # European GSM 06.10 is a provisional standard for full-rate speech
  78. # transcoding, prI-ETS 300 036, which uses RPE/LTP (residual pulse
  79. # excitation/long term prediction) coding at 13 kbit/s.
  80. #
  81. # There's only a magic nibble (4 bits); that nibble repeats every 33
  82. # bytes. This isn't suited for use, but maybe we can use it someday.
  83. #
  84. # This will cause very short GSM files to be declared as data and
  85. # mismatches to be declared as data too!
  86. #0 byte&0xF0 0xd0 data
  87. #>33 byte&0xF0 0xd0
  88. #>66 byte&0xF0 0xd0
  89. #>99 byte&0xF0 0xd0
  90. #>132 byte&0xF0 0xd0 GSM 06.10 compressed audio
  91. # bzip a block-sorting file compressor
  92. # by Julian Seward <sewardj@cs.man.ac.uk> and others
  93. #
  94. 0 string BZ bzip compressed data
  95. >2 byte x \b, version: %c
  96. >3 string =1 \b, compression block size 100k
  97. >3 string =2 \b, compression block size 200k
  98. >3 string =3 \b, compression block size 300k
  99. >3 string =4 \b, compression block size 400k
  100. >3 string =5 \b, compression block size 500k
  101. >3 string =6 \b, compression block size 600k
  102. >3 string =7 \b, compression block size 700k
  103. >3 string =8 \b, compression block size 800k
  104. >3 string =9 \b, compression block size 900k
  105. # lzop from <markus.oberhumer@jk.uni-linz.ac.at>
  106. 0 string \x89\x4c\x5a\x4f\x00\x0d\x0a\x1a\x0a lzop compressed data
  107. >9 beshort <0x0940
  108. >>9 byte&0xf0 =0x00 - version 0.
  109. >>9 beshort&0x0fff x \b%03x,
  110. >>13 byte 1 LZO1X-1,
  111. >>13 byte 2 LZO1X-1(15),
  112. >>13 byte 3 LZO1X-999,
  113. ## >>22 bedate >0 last modified: %s,
  114. >>14 byte =0x00 os: MS-DOS
  115. >>14 byte =0x01 os: Amiga
  116. >>14 byte =0x02 os: VMS
  117. >>14 byte =0x03 os: Unix
  118. >>14 byte =0x05 os: Atari
  119. >>14 byte =0x06 os: OS/2
  120. >>14 byte =0x07 os: MacOS
  121. >>14 byte =0x0A os: Tops/20
  122. >>14 byte =0x0B os: WinNT
  123. >>14 byte =0x0E os: Win32
  124. >9 beshort >0x0939
  125. >>9 byte&0xf0 =0x00 - version 0.
  126. >>9 byte&0xf0 =0x10 - version 1.
  127. >>9 byte&0xf0 =0x20 - version 2.
  128. >>9 beshort&0x0fff x \b%03x,
  129. >>15 byte 1 LZO1X-1,
  130. >>15 byte 2 LZO1X-1(15),
  131. >>15 byte 3 LZO1X-999,
  132. ## >>25 bedate >0 last modified: %s,
  133. >>17 byte =0x00 os: MS-DOS
  134. >>17 byte =0x01 os: Amiga
  135. >>17 byte =0x02 os: VMS
  136. >>17 byte =0x03 os: Unix
  137. >>17 byte =0x05 os: Atari
  138. >>17 byte =0x06 os: OS/2
  139. >>17 byte =0x07 os: MacOS
  140. >>17 byte =0x0A os: Tops/20
  141. >>17 byte =0x0B os: WinNT
  142. >>17 byte =0x0E os: Win32
  143. # 4.3BSD-Quasijarus Strong Compression
  144. # http://minnie.tuhs.org/Quasijarus/compress.html
  145. 0 string \037\241 Quasijarus strong compressed data
  146. # From: Cory Dikkers <cdikkers@swbell.net>
  147. 0 string XPKF Amiga xpkf.library compressed data
  148. 0 string PP11 Power Packer 1.1 compressed data
  149. 0 string PP20 Power Packer 2.0 compressed data,
  150. >4 belong 0x09090909 fast compression
  151. >4 belong 0x090A0A0A mediocre compression
  152. >4 belong 0x090A0B0B good compression
  153. >4 belong 0x090A0C0C very good compression
  154. >4 belong 0x090A0C0D best compression
  155. # 7-zip archiver, from Thomas Klausner (wiz@danbala.tuwien.ac.at)
  156. # http://www.7-zip.org or DOC/7zFormat.txt
  157. #
  158. 0 string 7z\274\257\047\034 7-zip archive data,
  159. >6 byte x version %d
  160. >7 byte x \b.%d
  161. # AFX compressed files (Wolfram Kleff)
  162. 2 string -afx- AFX compressed file data
  163. # Supplementary magic data for the file(1) command to support
  164. # rzip(1). The format is described in magic(5).
  165. #
  166. # Copyright (C) 2003 by Andrew Tridgell. You may do whatever you want with
  167. # this file.
  168. #
  169. 0 string RZIP rzip compressed data
  170. >4 byte x - version %d
  171. >5 byte x \b.%d
  172. >6 belong x (%d bytes)