The virtual AmigaOS runtime (aka Wine for Amiga 🙂
vamos is a tool that allows to run AmigaOS m68k binaries directly on your Mac. It emulates the AmigaOS by providing implementations for some functions of the Exec and DOS library. It will run typical console binaries that do not rely on user interface (intuition) or graphics stuff. Its main focus is to run old compilers and assemblers to have some sort of “cross” compilers. This approach will not run any applications or games using direct hardware register access – for this a machine emulator like P-UAE is the tool you will need…
vamos uses the native Musashi m68k CPU Emulator written in C to run m68k code. I added a simply memory interface that provides some RAM space for the program code and added an interface for python to trap library calls and emulate their behavior in Mac OS.
- Fast m68k CPU emulation with Musashi CPU Emulator
- Supports native library loading for application libs (e.g. SAS sc1.library)
- Dos Library supports: Locks, Files (Open, Read, Write, Seek, Close)
- Exec Library supports: AllocMem/Vec, LoadLibrary
- Many useful tracing and logging features
vamos contains a native library for the CPU/memory emulation. This library needs to be compiled first. All other code is python and runs directly out of the box.
Build the library with:
cd musashi make
This will create libmusashi.so|.dylib in this directory. Now you are ready to run vamos from the top-level directory!
vamos uses a configuration file as source for setup information. It is usually named .vamosrc and is first searched in the $HOME directory and then in the current directory. You can also use the -c option to specify an own config file. The config file uses the syntax of the well-known .ini files.
Additionally, you can specify the parameters also on the command line. These will overwrite the settings specified in a config file.
In the source archive see config/sample_vamosrc for an example config file.
vamos works internally with AmigaOS compatible file and path names. An AmigaOS absolute path is usually rooted in a volume (“volname:abs/path/file”). vamos automatically translates these paths to Mac system paths for file access. This is done by specifying a volume to system path mapping.
In the config file the section volumes contains this mapping:
[volumes] system=~/amiga/wb310 home=~ work=~/amiga/work shared=$HOME/amiga/shared
This example defines the volume names system:. home:, work:, and shared: and assigns them native paths on my Mac.
Note that the native path may contain ~ for your home directory. Even $ENV environment variable access is possible.
You can also specify volumes on the command line with:
./vamos -V system:~/amiga/wb310 -V work:. ..
By default vamos defines the root: volume name to be root of your file system (/). So every Mac system path can be mapped to an Amiga path.
If multiple volumes share subtrees in the file system then the Amiga volume is always assigned from the longest path match. E.g. in our example above the path ~/amiga/wb310/c is covered by system: and home: volume. The mapper then takes the longest match and thus this path is converted to system:c.
AmigaOS also allows to use assigns to introduce some kind of virtual volume names that map to other amiga paths. Many applications use this mechanism to find their install directory (sc:) or things like includes (include:) or libs (lib:).
vamos adapts this mechanism and allows to define assigns yourself in the config file or on the command line. The config file needs a section assigns:
[assigns] sc=shared:sc include=sc:include lib=sc:lib c=system:c,sc:c
Note: an assign might reference other assigns and also allows to specify multiple expansions seperated with commas.
Note2: assigns always map to amiga paths and never directly to system paths. Mac system paths are only allowed when defining volumes.
On the command line assigns are given by -a options:
./vamos -a c:system:c -a lib:sc:lib ...
If an assign is specified in the config file and later on the command line then the original assign in the config file is overwritten. You can extend an assign by writing a plus sign right at the beginning of the mapping:
./vamos -a c:+cool:c
This example will extend the c: assign that might be already defined in the config file and does not replace it.
2.2 Auto Assign
If an amiga path cannot be mapped to a Mac system path (because it uses undefined volume or assign names) then vamos will abort. You will then have to restart vamos and specify the required assign or volume mappings.
vamos also provides a feature called Auto Assign. If enabled then you assign a single amiga path prefix. If vamos then finds an unknown assign it will not abort vamos but implicitly map the assign to a directory in the given path prefix.
In the config file write this:
On the command line give the -A option:
./vamos -A system:
With this auto assign in place the unknown assign t: will be mapped to the amiga path system:t
3. Usage Examples
Pick an amiga binary (e.g. here I use the A68k assembler from aminet) and run it:
> ./vamos a68k Source file name is missing. 68000 Assembler - version 2.71 (April 16, 1991) Copyright 1985 by Brian R. Anderson AmigaDOS conversion copyright 1991 by Charlie Gibbs. Usage: a68k <source file> [-d[[!]<prefix>]] [-o<object file>] [-e[<equate file>]] [-p<page depth>] [-f] [-q[<quiet interval>]] [-g] [-s] [-h<header file>] [-t] [-i<include dirlist>] [-w[<hash size>][,<heap size>]] [-k] [-x] [-l[<listing file>]] [-y] [-m<small data offset>] [-z[<debug start>][,<debug end>]] [-n] Heap size default: -w2047,1024
Yehaw! What has happened? Vamos loaded the amiga binary and ran it in the m68k Emulation… The output you see was generated as output by a68k.
Let’s enable some verboseness during operation:
> ./vamos -v a68k 19:14:26.661 main: INFO: setting up main memory with 1024 KiB RAM: top=100000 19:14:26.661 main: INFO: loading binary: test_bin/a68k 19:14:26.663 main: INFO: args: (2) 19:14:26.692 main: INFO: setting up m68k 19:14:26.694 main: INFO: start cpu: 002004 ... 19:14:26.705 main: INFO: done (284836 cycles in 0.0025s -> 114.19 MHz, trap time 0.0083s)
Wow! The m68k in the emulation is running really fast: 114 MHz. The trap time mentioned there is the time spent in the Library emulation of vamos written in Python…
You can have more info during runtime by enabling logging channels with -l switch:
> ./vamos -l dos:info,exec:info a68k 19:18:10.840 exec: INFO: open exec.library V39 19:18:10.840 dos: INFO: dos fs handler port: fd0000 19:18:10.843 exec: INFO: SetSignals: new_signals=00000000 signal_mask=00003000 old_signals=00000000 19:18:10.845 dos: INFO: open dos.library V39 19:18:10.845 exec: INFO: OpenLibrary: 'dos.library' V0 -> [Lib:'dos.library',V0] 19:18:10.845 dos: INFO: Input: [FH:''(ami='<STDIN>',sys='',nc=False)@fe0000=B@3f8000] 19:18:10.845 dos: INFO: Output: [FH:''(ami='<STDOUT>',sys='',nc=False)@fe002c=B@3f800b] 19:18:10.845 dos: INFO: Open: name='*' (old/1005/rb) -> [FH:''(ami='*',sys='',nc=False)@fe0058=B@3f8016] 19:18:10.846 exec: INFO: SetSignals: new_signals=00000000 signal_mask=00003000 old_signals=00000000 Source file name is missing. 19:18:10.846 dos: INFO: Write([FH:''(ami='*',sys='',nc=False)@fe0058=B@3f8016], 00ffa0, 29) -> 29 19:18:10.846 exec: INFO: SetSignals: new_signals=00000000 signal_mask=00003000 old_signals=00000000 ...
Now you see what library calls occurred and how they were handled by vamos.
Use -L <file> to redirect the logging into a file instead of stdout.
You can even look deeper inside the workings of vamos by enabling memory tracing with -t (and -T for vamos’ own memory accesses during traps) (You have to specify -t/-T to enable memory tracing at all and then you will need to enable the according logging channels to see the traces). Memory tracing will catch each memory access of the CPU emulation and redirects it to vamos. This is very slow! So enable it only for debugging:
> ./vamos -t -T -l mem:info a68k 19:23:36.033 mem: INFO: R(2): 00f7c6: 4e70 TRAP [@00f5bc +00020a exec.library] -306  19:23:36.033 mem: INFO: R(2): 00f7c8: 4e75 TRAP [@00f5bc +00020c exec.library] -304  19:23:36.033 mem: INFO: R(2): 00f6d0: 4e70 TRAP [@00f5bc +000114 exec.library] -552  19:23:36.035 mem: INFO: R(2): 00f6d2: 4e75 TRAP [@00f5bc +000116 exec.library] -550  19:23:36.035 mem: INFO: R(4): 00fa0c: 0000f4d8 Struct [@00f5bc +000450 exec.library] ExecLibrary+276 = ThisTask(Task*)+0 19:23:36.035 mem: INFO: R(4): 00f570: 00000000 Struct [@00f4d8 +000098 ThisTask] Process+152 = pr_CurrentDir(BPTR)+0 19:23:36.036 mem: INFO: R(4): 00f584: 00003d22 Struct [@00f4d8 +0000ac ThisTask] Process+172 = pr_CLI(BPTR)+0 19:23:36.036 mem: INFO: R(4): 00f584: 00003d22 Struct [@00f4d8 +0000ac ThisTask] Process+172 = pr_CLI(BPTR)+0 19:23:36.036 mem: INFO: R(4): 00f498: 00003d32 Struct [@00f488 +000010 CLI] CLI+16 = cli_CommandName(BSTR)+0 19:23:36.037 mem: INFO: R(2): 00f832: 4e70 TRAP [@00f5bc +000276 exec.library] -198  19:23:36.037 mem: INFO: R(2): 00f834: 4e75 TRAP [@00f5bc +000278 exec.library] -196  19:23:36.043 mem: INFO: R(2): 00ff28: 4e70 TRAP [@00fb74 +0003b4 dos.library] -54  ...
Now you can see every trapped library call and even access to in memory structures… That’s very convenient for debugging! It even labels every memory location with a source description (library, code segment) and shows symbolic names of structure entries…
The lowest level is memory debugging on level debug. Then _every_ access to memory is logged:
> ./vamos -t -T -l mem:debug a68k 19:26:47.022 mem: DEBUG: R(4): 000000: 00001ff8 [@000000 +000000 zero_page] 19:26:47.022 mem: DEBUG: R(4): 000004: 00002004 [@000000 +000004 zero_page] 19:26:47.022 mem: DEBUG: R(2): 002004: 48e7 [@002004 +000000 a68k:0:code] 19:26:47.023 mem: DEBUG: R(2): 002006: 7efe [@002004 +000002 a68k:0:code] 19:26:47.023 mem: DEBUG: W(4): 001ff4: 00fc0000 [@001000 +000ff4 stack] 19:26:47.023 mem: DEBUG: W(4): 001ff0: 00fc0000 [@001000 +000ff0 stack] 19:26:47.023 mem: DEBUG: W(4): 001fec: 00000000 [@001000 +000fec stack] 19:26:47.023 mem: DEBUG: W(4): 001fe8: 00000000 [@001000 +000fe8 stack] 19:26:47.023 mem: DEBUG: W(4): 001fe4: 00fc0000 [@001000 +000fe4 stack] 19:26:47.023 mem: DEBUG: W(4): 001fe0: 00000000 [@001000 +000fe0 stack] 19:26:47.023 mem: DEBUG: W(4): 001fdc: 0000f484 [@001000 +000fdc stack] 19:26:47.023 mem: DEBUG: W(4): 001fd8: 00000000 [@001000 +000fd8 stack] 19:26:47.023 mem: DEBUG: W(4): 001fd4: 00000000 [@001000 +000fd4 stack] 19:26:47.024 mem: DEBUG: W(4): 001fd0: 00000000 [@001000 +000fd0 stack] 19:26:47.024 mem: DEBUG: W(4): 001fcc: 00000000 [@001000 +000fcc stack] 19:26:47.024 mem: DEBUG: W(4): 001fc8: 00000000 [@001000 +000fc8 stack] 19:26:47.024 mem: DEBUG: W(4): 001fc4: 00000000 [@001000 +000fc4 stack] 19:26:47.024 mem: DEBUG: R(2): 002008: 2448 [@002004 +000004 a68k:0:code] 19:26:47.024 mem: DEBUG: R(2): 00200a: 2400 [@002004 +000006 a68k:0:code] 19:26:47.024 mem: DEBUG: R(2): 00200c: 49f9 [@002004 +000008 a68k:0:code] 19:26:47.024 mem: DEBUG: R(4): 00200e: 0000d9c4 [@002004 +00000a a68k:0:code] 19:26:47.024 mem: DEBUG: R(2): 002012: 2c78 [@002004 +00000e a68k:0:code] 19:26:47.025 mem: DEBUG: R(2): 002014: 0004 [@002004 +000010 a68k:0:code] 19:26:47.025 mem: DEBUG: R(4): 000004: 0000f8f8 [@000000 +000004 zero_page] ...
This output is very useful to see all code fetches and have a look what code is running now. Use a hunktool disassembly side-by-side to check out whats going on or going wrong 😉
You can use the -c option to limit the program execution to a given number of cycles to keep the output short…
That’s it for now! Have fun playing with vamos!