#------------------------------------------------------------------------------ # $File: acorn,v 1.6 2017/10/19 16:40:37 christos Exp $ # acorn: file(1) magic for files found on Acorn systems # # RISC OS Chunk File Format # From RISC OS Programmer's Reference Manual, Appendix D # We guess the file type from the type of the first chunk. 0 lelong 0xc3cbc6c5 RISC OS Chunk data >12 string OBJ_ \b, AOF object >12 string LIB_ \b, ALF library # RISC OS AIF, contains "SWI OS_Exit" at offset 16. 16 lelong 0xef000011 RISC OS AIF executable # RISC OS Draw files # From RISC OS Programmer's Reference Manual, Appendix E 0 string Draw RISC OS Draw file data # RISC OS new format font files # From RISC OS Programmer's Reference Manual, Appendix E 0 string FONT\0 RISC OS outline font data, >5 byte x version %d 0 string FONT\1 RISC OS 1bpp font data, >5 byte x version %d 0 string FONT\4 RISC OS 4bpp font data >5 byte x version %d # RISC OS Music files # From RISC OS Programmer's Reference Manual, Appendix E 0 string Maestro\r RISC OS music file >8 byte x version %d >8 byte x type %d # Digital Symphony data files # From: Bernard Jungen (bern8817@euphonynet.be) 0 string \x02\x01\x13\x13\x13\x01\x0d\x10 Digital Symphony sound sample (RISC OS), >8 byte x version %d, >9 pstring x named "%s", >(9.b+19) byte =0 8-bit logarithmic >(9.b+19) byte =1 LZW-compressed linear >(9.b+19) byte =2 8-bit linear signed >(9.b+19) byte =3 16-bit linear signed >(9.b+19) byte =4 SigmaDelta-compressed linear >(9.b+19) byte =5 SigmaDelta-compressed logarithmic >(9.b+19) byte >5 unknown format 0 string \x02\x01\x13\x13\x14\x12\x01\x0b Digital Symphony song (RISC OS), >8 byte x version %d, >9 byte =1 1 voice, >9 byte !1 %d voices, >10 leshort =1 1 track, >10 leshort !1 %d tracks, >12 leshort =1 1 pattern >12 leshort !1 %d patterns 0 string \x02\x01\x13\x13\x10\x14\x12\x0e >9 byte =0 Digital Symphony sequence (RISC OS), >>8 byte x version %d, >>10 byte =1 1 line, >>10 byte !1 %d lines, >>11 leshort =1 1 position >>11 leshort !1 %d positions >9 byte =1 Digital Symphony pattern data (RISC OS), >>8 byte x version %d, >>10 leshort =1 1 pattern >>10 leshort !1 %d patterns # From: Joerg Jenderek # URL: https://www.kyzer.me.uk/pack/xad/#PackDir # reference: https://www.kyzer.me.uk/pack/xad/xad_PackDir.lha/PackDir.c # GRR: line below is too general as it matches also "Git pack" in ./revision 0 string PACK\0 # check for valid compression method 0-4 >5 ulelong <5 # https://www.riscosopen.org/wiki/documentation/show/Introduction%20To%20Filing%20Systems # To skip "Git pack" version 0 test for root directory object like # ADFS::RPC.$.websitezip.FONTFIX >>9 string >ADFS\ PackDir archive (RISC OS) # TrID labels above as "Acorn PackDir compressed Archive" # compression mode y (0 - 4) for GIF LZW with a maximum n bits # (y~n,0~12,1~13,2~14,3~15,4~16) >>>5 ulelong+12 x \b, LZW %u-bits compression # http://www.filebase.org.uk/filetypes # !Packdir compressed archive has three hexadecimal digits code 68E !:mime application/x-acorn-68E !:ext pkd/bin # null terminated root directory object like IDEFS::IDE-4.$.Apps.GRAPHICS.!XFMPdemo >>>9 string x \b, root "%s" # load address 0xFFFtttdd, ttt is the object filetype and dddddddddd is time >>>>&1 ulelong x \b, load address 0x%x # execution address 0xdddddddd dddddddddd is 40 bit unsigned centiseconds since 1.1.1900 UTC >>>>&5 ulelong x \b, exec address 0x%x # attributes (bits: 0~owner read,1~owner write,3~no delete,4~public read,5~public write) >>>>&9 ulelong x \b, attributes 0x%x # number of entries in this directory. for root dir 0 #>>>&13 ulelong x \b, entries 0x%x # the entries start here with object name >>>>&17 string x \b, 1st object "%s"