xref: /freebsd/contrib/file/magic/Magdir/acorn (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
1
2#------------------------------------------------------------------------------
3# $File: acorn,v 1.7 2019/04/19 00:42:27 christos Exp $
4# acorn:  file(1) magic for files found on Acorn systems
5#
6
7# RISC OS Chunk File Format
8# From RISC OS Programmer's Reference Manual, Appendix D
9# We guess the file type from the type of the first chunk.
100	lelong		0xc3cbc6c5	RISC OS Chunk data
11>12	string		OBJ_		\b, AOF object
12>12	string		LIB_		\b, ALF library
13
14# RISC OS AIF, contains "SWI OS_Exit" at offset 16.
1516	lelong		0xef000011	RISC OS AIF executable
16
17# RISC OS Draw files
18# From RISC OS Programmer's Reference Manual, Appendix E
190	string 		Draw		RISC OS Draw file data
20
21# RISC OS new format font files
22# From RISC OS Programmer's Reference Manual, Appendix E
230	string		FONT\0		RISC OS outline font data,
24>5	byte		x		version %d
250	string		FONT\1		RISC OS 1bpp font data,
26>5	byte		x		version %d
270	string		FONT\4		RISC OS 4bpp font data
28>5	byte		x		version %d
29
30# RISC OS Music files
31# From RISC OS Programmer's Reference Manual, Appendix E
320	string		Maestro\r	RISC OS music file
33>8	byte		x		version %d
34
35>8	byte		x		type %d
36
37# Digital Symphony data files
38# From: Bernard Jungen (bern8817@euphonynet.be)
390		string	\x02\x01\x13\x13\x13\x01\x0d\x10	Digital Symphony sound sample (RISC OS),
40>8		byte	x	version %d,
41>9		pstring	x	named "%s",
42>(9.b+19)	byte	=0	8-bit logarithmic
43>(9.b+19)	byte	=1	LZW-compressed linear
44>(9.b+19)	byte	=2	8-bit linear signed
45>(9.b+19)	byte	=3	16-bit linear signed
46>(9.b+19)	byte	=4	SigmaDelta-compressed linear
47>(9.b+19)	byte	=5	SigmaDelta-compressed logarithmic
48>(9.b+19)	byte	>5	unknown format
49
500	string	\x02\x01\x13\x13\x14\x12\x01\x0b	Digital Symphony song (RISC OS),
51>8	byte	x	version %d,
52>9	byte	=1	1 voice,
53>9	byte	!1	%d voices,
54>10	leshort	=1	1 track,
55>10	leshort	!1	%d tracks,
56>12	leshort	=1	1 pattern
57>12	leshort	!1	%d patterns
58
590	string	\x02\x01\x13\x13\x10\x14\x12\x0e
60>9	byte	=0	Digital Symphony sequence (RISC OS),
61>>8	byte	x	version %d,
62>>10	byte	=1	1 line,
63>>10	byte	!1	%d lines,
64>>11	leshort	=1	1 position
65>>11	leshort	!1	%d positions
66>9	byte	=1	Digital Symphony pattern data (RISC OS),
67>>8	byte	x	version %d,
68>>10	leshort	=1	1 pattern
69>>10	leshort	!1	%d patterns
70
71# From: Joerg Jenderek
72# URL: https://www.kyzer.me.uk/pack/xad/#PackDir
73# reference: https://www.kyzer.me.uk/pack/xad/xad_PackDir.lha/PackDir.c
74# GRR: line below is too general as it matches also "Git pack" in ./revision
750	string	PACK\0
76# check for valid compression method 0-4
77>5	ulelong	<5
78# https://www.riscosopen.org/wiki/documentation/show/Introduction%20To%20Filing%20Systems
79# To skip "Git pack" version 0 test for root directory object like
80# ADFS::RPC.$.websitezip.FONTFIX
81>>9	string	>ADFS\  PackDir archive (RISC OS)
82# TrID labels above as "Acorn PackDir compressed Archive"
83# compression mode y (0 - 4) for GIF LZW with a maximum n bits
84# (y~n,0~12,1~13,2~14,3~15,4~16)
85>>>5	ulelong+12 x	\b, LZW %u-bits compression
86# https://www.filebase.org.uk/filetypes
87# !Packdir compressed archive has three hexadecimal digits code 68E
88!:mime	application/x-acorn-68E
89!:ext	pkd/bin
90# null terminated root directory object like IDEFS::IDE-4.$.Apps.GRAPHICS.!XFMPdemo
91>>>9	string	x	\b, root "%s"
92# load address 0xFFFtttdd, ttt is the object filetype and dddddddddd is time
93>>>>&1	ulelong	x	\b, load address 0x%x
94# execution address 0xdddddddd dddddddddd is 40 bit unsigned centiseconds since 1.1.1900 UTC
95>>>>&5	ulelong	x	\b, exec address 0x%x
96# attributes (bits: 0~owner read,1~owner write,3~no delete,4~public read,5~public write)
97>>>>&9	ulelong	x	\b, attributes 0x%x
98# number of entries in this directory. for root dir 0
99#>>>&13	ulelong	x	\b, entries 0x%x
100# the entries start here with object name
101>>>>&17	string	x	\b, 1st object "%s"
102
103