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Revision: 1.4
Committed: 2000-09-25T12:44:30Z (24 years, 1 month ago) by cebix
Branch: MAIN
Changes since 1.3: +11 -10 lines
Log Message:
- replaced 680x0 and 80x86 disassemblers with the ones from GNU binutils
- 680x0 disassembler shows symbolic MacOS low memory globals

File Contents

# User Rev Content
1 cebix 1.1
2 cebix 1.4 mon, Version 3.0
3     A command-driven file monitor
4 cebix 1.1
5 cebix 1.4 Copyright (C) 1997-2000 Christian Bauer, Marc Hellwig
6     GNU binutils disassemblers (C) 1988, 89, 91, 93, 94, 95, 96, 97, 1998
7     Free Software Foundation, Inc.
8 cebix 1.1
9    
10 cebix 1.2 License
11     -------
12    
13     mon is available under the terms of the GNU General Public License. See the
14     file "COPYING" that is included in the distribution for details.
15    
16    
17 cebix 1.1 Overview
18     --------
19    
20     "mon" is an interactive command-driven file manipulation tool that is inspired
21     by the "Amiga Monitor" by Timo Rossi <trossi@jyu.fi>. It has commands and
22     features similar to a machine code monitor/debugger, but it is not intended
23     to be used for debugging. It doesn't operate on physical or virtual RAM
24     locations of a process but rather on a fixed-size (but adjustable) buffer with
25     adresses starting at 0. Also, there are no commands to trace code, set
26 cebix 1.4 breakpoints etc. There are, however, built-in PowerPC, 680x0, 80x86, 6502 and
27     8080 disassemblers.
28 cebix 1.1
29    
30     Installation
31     ------------
32    
33 cebix 1.2 Please consult the file "INSTALL" for installation instructions.
34 cebix 1.1
35    
36     Usage
37     -----
38    
39     mon can be started from the Shell or from the Tracker (BeOS), but command line
40     history doesn't work when started from the Tracker). If you give no command
41     line arguments, mon enters interactive mode. Otherwise, all arguments are
42     interpreted and executed as mon commands. The default buffer size is 1MB.
43     The mon command prompt looks like this:
44    
45     [00000000]->
46    
47     The number in brackets is the value of "." (the "current address", see the
48     section on expressions). You can get a short command overview by entering
49     "h".
50    
51     Commands that create a longer output can be interrupted with Ctrl-C.
52    
53     To quit mon, enter the command "x".
54    
55    
56     Constants, variables and expressions
57     ------------------------------------
58    
59     The default number base is hexadecimal. Decimal numbers must be prefixed with
60     "_". Hexadecimal numbers may also be prefixed with "$" for clarity. Numbers
61     can also be entered as ASCII characters enclosed in single quotes (e.g. 'BAPP'
62     is the same as $42415050). All numbers are 32-bit values (one word).
63    
64     With the "set" command, variables can be defined that hold 32-bit integer
65     values. A variable is referred to by its name. Variable names may be arbitrary
66     combinations of digits and letters (they may also start with a digit) that
67     are not also valid hexadecimal numbers. Names are case-sensitive.
68    
69     mon accepts expressions in all places where you have to specify a number. The
70     following operators are available and have the same meaning and precedence as
71     in the C programming language:
72    
73     ~ complement
74     + unary plus
75     - unary minus
76     * multiplication
77     / integer division
78     % modulo
79     + addition
80     - subtraction
81     << shift left
82     >> shift right
83     & bitwise AND
84     ^ bitwise exclusive OR
85     | bitwise inclusive OR
86    
87     Parentheses may be used to change the evaluation order of sub-expressions.
88    
89     There are two special symbols that can be used in expressions:
90    
91     . represents the "current address" (the value of "." is also displayed in
92     the command prompt). What exactly the current address is, depends on the
93     command last executed. The display commands set "." to the address after
94     the last address displayed, the "hunt" commands sets "." to the address
95     of the first found occurence of the search string, etc.
96     : is used by the "apply" ("y") command and holds the value of the byte/
97     half-word/word at the current address.
98    
99     The "modify" (":"), "fill" ("f") and "hunt" ("h") commands require you to
100     specify a byte string. Byte strings consist of an arbitrary number of byte
101     values and ASCII strings separated by commas. Examples:
102    
103     "string"
104     12,34,56,78,9a,bc,de,f0
105     "this",0a,"is a string",0a,"with","newlines",_10
106    
107    
108     The buffer
109     ----------
110    
111     Those mon commands that operate on "memory" operate on a buffer allocated by
112     mon whose size is adjustable with the "@" command. The default buffer size is
113     1MB. The buffer is an array of bytes where each byte has a 32-bit integer
114     address. Addresses start at 0 and are taken modulo the buffer size (i.e. for
115     the default 1MB buffer, addresses 0 and 100000 refer to the same byte).
116    
117     The buffer is the working area of mon where you load files into, manipulate
118     them, and write files back from. Arbitraty portions of the buffer may be used
119     as scratch space.
120    
121    
122     Commands
123     --------
124    
125     The following commands are available in mon ('[]' marks a parameter than can be
126     left out):
127    
128    
129     x Quit mon
130    
131     quits mon and returns to the shell.
132    
133    
134     h Show help text
135    
136     displays a short overview of commands.
137    
138    
139     ?? Show list of commands
140    
141     displays a short list of available commands.
142    
143    
144     ver Show version
145    
146     shows the version number of mon.
147    
148    
149     ? expression Calculate expression
150    
151     displays the value of the given expression in hex, decimal, and ASCII
152     characters. If the value is negative, it is displayed as a signed and unsigned
153     number.
154    
155    
156     @ [size] Reallocate buffer
157    
158     changes the size of the buffer to the given number of bytes while preserving
159     the contents of the buffer. If the "size" argument is omitted, the current
160     buffer size is displayed.
161    
162    
163     i [start [end]] ASCII memory dump
164    
165     displays the buffer contents from address "start" to address "end" as ASCII
166     characters. Entering "i" without arguments is equivalent to "i .". The value
167     of "." is set to the address after the last address displayed.
168    
169    
170 cebix 1.3 b [start [end]] Binary memory dump
171    
172     displays the buffer contents from address "start" to address "end" in a binary
173     format. Entering "b" without arguments is equivalent to "b .". The value of
174     "." is set to the address after the last address displayed.
175    
176    
177 cebix 1.1 m [start [end]] Hex/ASCII memory dump
178    
179     displays the buffer contents from address "start" to address "end" as hex
180     words and ASCII characters. Entering "m" without arguments is equivalent to
181     "m .". The value of "." is set to the address after the last address displayed.
182    
183    
184     d [start [end]] Disassemble PowerPC code
185    
186     disassembles the buffer contents from address "start" to address "end".
187     Entering "d" without arguments is equivalent to "d .". The value of "." is
188     set to the address after the last address displayed.
189    
190    
191 cebix 1.4 d65 [start [end]] Disassemble 6502 code
192 cebix 1.1
193     disassembles the buffer contents from address "start" to address "end".
194     Entering "d65" without arguments is equivalent to "d65 .". The value of
195     "." is set to the address after the last address displayed.
196    
197    
198 cebix 1.4 d68 [start [end]] Disassemble 680x0 code
199 cebix 1.1
200     disassembles the buffer contents from address "start" to address "end".
201     Entering "d68" without arguments is equivalent to "d68 .". The value of
202     "." is set to the address after the last address displayed.
203    
204    
205 cebix 1.4 d80 [start [end]] Disassemble 8080 code
206 cebix 1.1
207     disassembles the buffer contents from address "start" to address "end".
208     Entering "d80" without arguments is equivalent to "d80 .". The value of
209     "." is set to the address after the last address displayed.
210    
211    
212 cebix 1.4 d86 [start [end]] Disassemble 80x86 code
213 cebix 1.1
214     disassembles the buffer contents from address "start" to address "end".
215     Entering "d86" without arguments is equivalent to "d86 .". The value of
216     "." is set to the address after the last address displayed.
217    
218    
219     : start string Modify memory
220    
221     puts the specified byte string at the address "start" into the buffer. The
222     value of "." is set to the address after the last address modified.
223    
224    
225     f start end string Fill memory
226    
227     fill the buffer in the range from "start" to (and including) "end" with the
228     given byte string.
229    
230    
231     y[b|h|w] start end expr Apply expression to memory
232    
233     works like the "fill" ("f") command, but it doesn't fill with a byte string
234     but with the value of an expression that is re-evaluated for each buffer
235     location to be filled. The command comes in three flavors: "y"/"yb" works on
236     bytes (8-bit), "yh" on half-words (16-bit) and "yw" on words (32-bit). The
237     value of "." is the current address to be modified, the value of ":" holds
238     the contents of this address before modification.
239    
240     Examples:
241     yw 0 fff :<<8 shifts all words in the address range 0..fff to the left
242     by 8 bits (you can use this to convert bitmap data from
243     ARGB to RGBA format, for example)
244     y 0 1234 ~: inverts all bytes in the address range 0..1234
245     yh 2 ff 20000/. creates a table of the fractional parts of the reciprocals
246     of 1..7f
247    
248    
249     t start end dest Transfer memory
250    
251     transfers the buffer contents from "start" to (and including) "end" to "dest".
252     Source and destination may overlap.
253    
254    
255     c start end dest Compare memory
256    
257     compares the buffer contents in the range from "start" to (and including)
258     "end" with the contents at "dest". The addresses of all different bytes and
259     the total number of differences (decimal) are printed.
260    
261    
262     h start end string Search for byte string
263    
264     searches for the given byte string in the buffer starting at "start" up to
265     (and including) "end". The addresses and the total number of occurrences are
266     displayed. The value of "." is set to the address of the first occurrence.
267    
268    
269     \ "command" Execute shell command
270    
271     executes the given shell command which must be enclosed in quotes.
272    
273    
274     ls [args] List directory contents
275    
276     works as the shell command "ls".
277    
278    
279     rm [args] Remove file(s)
280    
281     works as the shell command "rm".
282    
283    
284     cp [args] Copy file(s)
285    
286     works as the shell command "cp".
287    
288    
289     mv [args] Move file(s)
290    
291     works as the shell command "mv".
292    
293    
294     cd directory Change current directory
295    
296     works as the shell command "cd". The name of the directory doesn't have to be
297     enclosed in quotes.
298    
299    
300     o ["file"] Redirect output
301    
302     When a file name is specified, all following output is redirected to this
303     file. The file name must be enclosed in quotation marks even if it contains
304     no spaces. Entering "o" without parameters closes the file and directs the
305     output into the terminal window again.
306    
307    
308     [ start "file" Load data from file
309    
310     loads the contents of the specified file into the buffer starting from address
311     "start". The file name must be enclosed in quotation marks even if it contains
312     no spaces. The value of "." is set to the address after the last address
313     affected by the load.
314    
315    
316     ] start size "file" Save data to file
317    
318     writes "size" number of bytes of the buffer from "start" to the specified file.
319     The file name must be enclosed in quotation marks even if it contains no spaces.
320    
321    
322     set [var[=value]] Set/clear/show variables
323    
324     If no arguments are given, all currently defined variables are displayed.
325     Otherwise, the value of "var" is set to the specified value. If "=value"
326     is omitted, the variable "var" is cleared.
327    
328    
329     cv Clear all variables
330    
331     clears all currently defined variables.
332    
333    
334     rmon
335     ----
336    
337     When mon is started as "rmon", it enters "real mode". That is, all memory
338     related functions no longer operate on the buffer but on "real" (virtual)
339     memory. Unless you are writing Mac emulators, this is probably of not much
340     use. :-)
341    
342    
343     Examples
344     --------
345    
346     Here are some simple examples for what is possible with mon.
347    
348     Join "file1" and "file2" to "file3":
349    
350     [ 0 "file1"
351     [ . "file2"
352     ] 0 . "file3"
353    
354     Remove the first 24 bytes (e.g. an unneeded header) of a file:
355    
356     [ 0 "file"
357     ] 18 .-18 "file"
358    
359     Load the mon executable and search for PowerPC "nop" commands:
360    
361     [ 0 "mon"
362     h 0 . 60,00,00,00
363    
364     Create a modified version of mon so that the prompt has " $" instead of "->":
365    
366     [ 0 "mon"
367     set size=.
368     h 0 . "->"
369     : . " $"
370     ] 0 size "mon1"
371    
372     Convert a binary file which contains 16-bit numbers in little-endian format
373     to big-endian format (or vice-versa):
374    
375     [ 0 "file"
376     yh 0 .-1 :>>8|:<<8
377     ] 0 . "file"
378    
379     Load a BeBox boot ROM image and start disassembling the system reset handler:
380    
381     [ 0 "bootnub.image"
382     d 100
383    
384    
385     History
386     -------
387    
388 cebix 1.2 Please consult the file "ChangeLog" for the release history.
389 cebix 1.1
390    
391     Christian Bauer
392 cebix 1.2 <Christian.Bauer@uni-mainz.de>
393 cebix 1.1
394     Marc Hellwig
395 cebix 1.2 <Marc.Hellwig@uni-mainz.de>