[ViewVC] Contents of: cebix/mon/README


  cxmon, Version 3.0
  A command-line file manipulation tool and disassembler

  Copyright (C) 1997-2000 Christian Bauer, Marc Hellwig
  GNU binutils disassemblers Copyright (C) 1988, 89, 91, 93, 94, 95, 96, 97, 1998
    Free Software Foundation, Inc.


License
-------

cxmon is available under the terms of the GNU General Public License. See the
file "COPYING" that is included in the distribution for details.


Overview
--------

cxmon is an interactive command-driven file manipulation tool that is
inspired by the "Amiga Monitor" by Timo Rossi. It has commands and features
similar to a machine code monitor/debugger, but it lacks any functions for
running/tracing code. There are, however, built-in PowerPC, 680x0, 80x86,
6502 and Z80 disassemblers and special support for disassembling MacOS code.
By default, cxmon operates on a fixed-size (but adjustable) memory buffer
with adresses starting at 0.


Installation
------------

Please consult the file "INSTALL" for installation instructions.


Usage
-----

cxmon can be started from the Shell or from the Tracker (BeOS), but command
line history doesn't work when started from the Tracker.

Options:
  -m  enables symbolic MacOS A-Trap and low memory globals display in the
      680x0 disassembler
  -r  makes cxmon operate in real (virtual) memory space instead of an
      allocated buffer

If no additional command line arguments are given, cxmon enters interactive
mode. Otherwise, all remaining arguments are interpreted and executed as cxmon
commands.

The default buffer size is 1MB.

The cxmon command prompt looks like this:

  [00000000]->

The number in brackets is the value of "." (the "current address", see the
section on expressions). You can get a short command overview by entering
"h".

Commands that create a longer output can be interrupted with Ctrl-C.

To quit cxmon, enter the command "x".


Constants, variables and expressions
------------------------------------

The default number base is hexadecimal. Decimal numbers must be prefixed with
"_". Hexadecimal numbers may also be prefixed with "$" for clarity. Numbers
can also be entered as ASCII characters enclosed in single quotes (e.g. 'BAPP'
is the same as $42415050). All numbers are 32-bit values (one word).

With the "set" command, variables can be defined that hold 32-bit integer
values. A variable is referred to by its name. Variable names may be arbitrary
combinations of digits and letters (they may also start with a digit) that
are not also valid hexadecimal numbers. Names are case-sensitive.

cxmon accepts expressions in all places where you have to specify a number.
The following operators are available and have the same meaning and
precedence as in the C programming language:

  ~   complement
  +   unary plus
  -   unary minus
  *   multiplication
  /   integer division
  %   modulo
  +   addition
  -   subtraction
  <<  shift left
  >>  shift right
  &   bitwise AND
  ^   bitwise exclusive OR
  |   bitwise inclusive OR

Parentheses may be used to change the evaluation order of sub-expressions.

There are two special symbols that can be used in expressions:

  .   represents the "current address" (the value of "." is also displayed in
      the command prompt). What exactly the current address is, depends on the
      command last executed. The display commands set "." to the address after
      the last address displayed, the "hunt" commands sets "." to the address
      of the first found occurence of the search string, etc.
  :   is used by the "apply" ("y") command and holds the value of the byte/
      half-word/word at the current address.

The "modify" (":"), "fill" ("f") and "hunt" ("h") commands require you to
specify a byte string. Byte strings consist of an arbitrary number of byte
values and ASCII strings separated by commas. Examples:

  "string"
  12,34,56,78,9a,bc,de,f0
  "this",0a,"is a string",0a,"with","newlines",_10


The buffer
----------

Those cxmon commands that operate on "memory" operate on a buffer allocated
by cxmon whose size is adjustable with the "@" command. The default buffer
size is 1MB. The buffer is an array of bytes where each byte has a 32-bit
integer address. Addresses start at 0 and are taken modulo the buffer size
(i.e. for the default 1MB buffer, addresses 0 and 100000 refer to the same
byte).

The buffer is the working area of cxmon where you load files into, manipulate
them, and write files back from. Arbitraty portions of the buffer may be used
as scratch space.


Commands
--------

The following commands are available in cxmon ('[]' marks a parameter than
can be left out):


  x                        Quit cxmon

quits cxmon and returns to the shell.


  h                        Show help text

displays a short overview of commands.


  ??                       Show list of commands

displays a short list of available commands.


  ver                      Show version

shows the version number of cxmon.


  ? expression             Calculate expression

displays the value of the given expression in hex, decimal, and ASCII
characters. If the value is negative, it is displayed as a signed and unsigned
number.


  @ [size]                 Reallocate buffer

changes the size of the buffer to the given number of bytes while preserving
the contents of the buffer. If the "size" argument is omitted, the current
buffer size is displayed.


  i [start [end]]          ASCII memory dump

displays the buffer contents from address "start" to address "end" as ASCII
characters. Entering "i" without arguments is equivalent to "i .". The value
of "." is set to the address after the last address displayed.


  b [start [end]]          Binary memory dump

displays the buffer contents from address "start" to address "end" in a binary
format. Entering "b" without arguments is equivalent to "b .". The value of
"." is set to the address after the last address displayed.


  m [start [end]]          Hex/ASCII memory dump

displays the buffer contents from address "start" to address "end" as hex
words and ASCII characters. Entering "m" without arguments is equivalent to
"m .". The value of "." is set to the address after the last address displayed.


  d [start [end]]          Disassemble PowerPC code

disassembles the buffer contents from address "start" to address "end".
Entering "d" without arguments is equivalent to "d .". The value of "." is
set to the address after the last address displayed.


  d65 [start [end]]        Disassemble 6502 code

disassembles the buffer contents from address "start" to address "end".
Entering "d65" without arguments is equivalent to "d65 .". The value of
"." is set to the address after the last address displayed.


  d68 [start [end]]        Disassemble 680x0 code

disassembles the buffer contents from address "start" to address "end".
Entering "d68" without arguments is equivalent to "d68 .". The value of
"." is set to the address after the last address displayed.


  d80 [start [end]]        Disassemble Z80 code

disassembles the buffer contents from address "start" to address "end".
Entering "d80" without arguments is equivalent to "d80 .". The value of
"." is set to the address after the last address displayed.


  d86 [start [end]]        Disassemble 80x86 (32-bit) code

disassembles the buffer contents from address "start" to address "end".
Entering "d86" without arguments is equivalent to "d86 .". The value of
"." is set to the address after the last address displayed.


  d8086 [start [end]]      Disassemble 80x86 (16-bit) code

disassembles the buffer contents from address "start" to address "end".
Entering "d8086" without arguments is equivalent to "d8086 .". The value
of "." is set to the address after the last address displayed.


  : start string           Modify memory

puts the specified byte string at the address "start" into the buffer. The
value of "." is set to the address after the last address modified.


  f start end string       Fill memory

fill the buffer in the range from "start" to (and including) "end" with the
given byte string.


  y[b|h|w] start end expr  Apply expression to memory

works like the "fill" ("f") command, but it doesn't fill with a byte string
but with the value of an expression that is re-evaluated for each buffer
location to be filled. The command comes in three flavors: "y"/"yb" works on
bytes (8-bit), "yh" on half-words (16-bit) and "yw" on words (32-bit). The
value of "." is the current address to be modified,  the value of ":" holds
the contents of this address before modification.

Examples:
  yw 0 fff :<<8    shifts all words in the address range 0..fff to the left
                   by 8 bits (you can use this to convert bitmap data from
                   ARGB to RGBA format, for example)
  y 0 1234 ~:      inverts all bytes in the address range 0..1234
  yh 2 ff 20000/.  creates a table of the fractional parts of the reciprocals
                   of 1..7f


  t start end dest         Transfer memory

transfers the buffer contents from "start" to (and including) "end" to "dest".
Source and destination may overlap.


  c start end dest         Compare memory

compares the buffer contents in the range from "start" to (and including)
"end" with the contents at "dest". The addresses of all different bytes and
the total number of differences (decimal) are printed.


  h start end string       Search for byte string

searches for the given byte string in the buffer starting at "start" up to
(and including) "end". The addresses and the total number of occurrences are
displayed. The value of "." is set to the address of the first occurrence. 


  \ "command"              Execute shell command

executes the given shell command which must be enclosed in quotes.


  ls [args]                List directory contents

works as the shell command "ls".


  rm [args]                Remove file(s)

works as the shell command "rm".


  cp [args]                Copy file(s)

works as the shell command "cp".


  mv [args]                Move file(s)

works as the shell command "mv".


  cd directory             Change current directory

works as the shell command "cd". The name of the directory doesn't have to be
enclosed in quotes.


  o ["file"]               Redirect output

When a file name is specified, all following output is redirected to this
file. The file name must be enclosed in quotation marks even if it contains
no spaces. Entering "o" without parameters closes the file and directs the
output into the terminal window again.


  [ start "file"           Load data from file

loads the contents of the specified file into the buffer starting from address
"start". The file name must be enclosed in quotation marks even if it contains
no spaces. The value of "." is set to the address after the last address
affected by the load.


  ] start size "file"      Save data to file

writes "size" number of bytes of the buffer from "start" to the specified file.
The file name must be enclosed in quotation marks even if it contains no spaces.


  set [var[=value]]        Set/clear/show variables

If no arguments are given, all currently defined variables are displayed.
Otherwise, the value of "var" is set to the specified value. If "=value"
is omitted, the variable "var" is cleared.


  cv                       Clear all variables

clears all currently defined variables.


Examples
--------

Here are some simple examples for what is possible with cxmon.

Join "file1" and "file2" to "file3":

  [ 0 "file1"
  [ . "file2"
  ] 0 . "file3"

Remove the first 24 bytes (e.g. an unneeded header) of a file:

  [ 0 "file"
  ] 18 .-18 "file"

Load the cxmon executable and search for PowerPC "nop" commands:

  [ 0 "cxmon"
  h 0 . 60,00,00,00

Create a modified version of cxmon so that the prompt has " $" instead of
"->":

  [ 0 "cxmon"
  set size=.
  h 0 . "->"
  : . " $"
  ] 0 size "cxmon1"

Convert a binary file which contains 16-bit numbers in little-endian format
to big-endian format (or vice-versa):

  [ 0 "file"
  yh 0 .-1 :>>8|:<<8  
  ] 0 . "file"

Load a BeBox boot ROM image and start disassembling the system reset handler:

  [ 0 "bootnub.image"
  d 100


Using cxmon in your own programs
--------------------------------

cxmon provides a simple interface for integration in other programs. It can,
for example, be used as a monitor/debugger for an emulator (it is used in
Basilisk II in this way).

Here's how to do it (all functions are defined in the mon.h header file):

 1. Link all the cxmon object files, except main.o, to your program.
 2. In your program, call mon_init() before using any other cxmon functions.
 3. After calling mon_init(), set the mon_read_byte and mon_write_byte
    function pointers to the routines used for accessing memory.
 4. You can use mon_add_command() to add new commands to cxmon by specifying
    the command name, function and help text. From within your command
    function, you can use mon_get_token() and mon_expression() to parse the
    arguments and the mon_read/write_*() functions to access memory.
 5. To enter cxmon, call the mon() function like this:

      char *args[3] = {"mon", "-r", NULL};
      mon(2, args);

 6. If you're done with cxmon, call mon_exit().


History
-------

Please consult the file "ChangeLog" for the release history.


Christian Bauer
<Christian.Bauer@uni-mainz.de>

Marc Hellwig
<Marc.Hellwig@uni-mainz.de>
Revision:	1.10
Committed:	2000-10-18T13:42:55Z (24 years, 1 month ago) by cebix
Branch:	MAIN
Changes since 1.9:	+6 -5 lines
Log Message:	updated docs
#	Content
1
2	cxmon, Version 3.0
3	A command-line file manipulation tool and disassembler
4
5	Copyright (C) 1997-2000 Christian Bauer, Marc Hellwig
6	GNU binutils disassemblers Copyright (C) 1988, 89, 91, 93, 94, 95, 96, 97, 1998
7	Free Software Foundation, Inc.
8
9
10	License
11	-------
12
13	cxmon 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	Overview
18	--------
19
20	cxmon is an interactive command-driven file manipulation tool that is
21	inspired by the "Amiga Monitor" by Timo Rossi. It has commands and features
22	similar to a machine code monitor/debugger, but it lacks any functions for
23	running/tracing code. There are, however, built-in PowerPC, 680x0, 80x86,
24	6502 and Z80 disassemblers and special support for disassembling MacOS code.
25	By default, cxmon operates on a fixed-size (but adjustable) memory buffer
26	with adresses starting at 0.
27
28
29	Installation
30	------------
31
32	Please consult the file "INSTALL" for installation instructions.
33
34
35	Usage
36	-----
37
38	cxmon can be started from the Shell or from the Tracker (BeOS), but command
39	line history doesn't work when started from the Tracker.
40
41	Options:
42	-m enables symbolic MacOS A-Trap and low memory globals display in the
43	680x0 disassembler
44	-r makes cxmon operate in real (virtual) memory space instead of an
45	allocated buffer
46
47	If no additional command line arguments are given, cxmon enters interactive
48	mode. Otherwise, all remaining arguments are interpreted and executed as cxmon
49	commands.
50
51	The default buffer size is 1MB.
52
53	The cxmon command prompt looks like this:
54
55	[00000000]->
56
57	The number in brackets is the value of "." (the "current address", see the
58	section on expressions). You can get a short command overview by entering
59	"h".
60
61	Commands that create a longer output can be interrupted with Ctrl-C.
62
63	To quit cxmon, enter the command "x".
64
65
66	Constants, variables and expressions
67	------------------------------------
68
69	The default number base is hexadecimal. Decimal numbers must be prefixed with
70	"_". Hexadecimal numbers may also be prefixed with "$" for clarity. Numbers
71	can also be entered as ASCII characters enclosed in single quotes (e.g. 'BAPP'
72	is the same as $42415050). All numbers are 32-bit values (one word).
73
74	With the "set" command, variables can be defined that hold 32-bit integer
75	values. A variable is referred to by its name. Variable names may be arbitrary
76	combinations of digits and letters (they may also start with a digit) that
77	are not also valid hexadecimal numbers. Names are case-sensitive.
78
79	cxmon accepts expressions in all places where you have to specify a number.
80	The following operators are available and have the same meaning and
81	precedence as in the C programming language:
82
83	~ complement
84	+ unary plus
85	- unary minus
86	* multiplication
87	/ integer division
88	% modulo
89	+ addition
90	- subtraction
91	<< shift left
92	>> shift right
93	& bitwise AND
94	^ bitwise exclusive OR
95	\| bitwise inclusive OR
96
97	Parentheses may be used to change the evaluation order of sub-expressions.
98
99	There are two special symbols that can be used in expressions:
100
101	. represents the "current address" (the value of "." is also displayed in
102	the command prompt). What exactly the current address is, depends on the
103	command last executed. The display commands set "." to the address after
104	the last address displayed, the "hunt" commands sets "." to the address
105	of the first found occurence of the search string, etc.
106	: is used by the "apply" ("y") command and holds the value of the byte/
107	half-word/word at the current address.
108
109	The "modify" (":"), "fill" ("f") and "hunt" ("h") commands require you to
110	specify a byte string. Byte strings consist of an arbitrary number of byte
111	values and ASCII strings separated by commas. Examples:
112
113	"string"
114	12,34,56,78,9a,bc,de,f0
115	"this",0a,"is a string",0a,"with","newlines",_10
116
117
118	The buffer
119	----------
120
121	Those cxmon commands that operate on "memory" operate on a buffer allocated
122	by cxmon whose size is adjustable with the "@" command. The default buffer
123	size is 1MB. The buffer is an array of bytes where each byte has a 32-bit
124	integer address. Addresses start at 0 and are taken modulo the buffer size
125	(i.e. for the default 1MB buffer, addresses 0 and 100000 refer to the same
126	byte).
127
128	The buffer is the working area of cxmon where you load files into, manipulate
129	them, and write files back from. Arbitraty portions of the buffer may be used
130	as scratch space.
131
132
133	Commands
134	--------
135
136	The following commands are available in cxmon ('[]' marks a parameter than
137	can be left out):
138
139
140	x Quit cxmon
141
142	quits cxmon and returns to the shell.
143
144
145	h Show help text
146
147	displays a short overview of commands.
148
149
150	?? Show list of commands
151
152	displays a short list of available commands.
153
154
155	ver Show version
156
157	shows the version number of cxmon.
158
159
160	? expression Calculate expression
161
162	displays the value of the given expression in hex, decimal, and ASCII
163	characters. If the value is negative, it is displayed as a signed and unsigned
164	number.
165
166
167	@ [size] Reallocate buffer
168
169	changes the size of the buffer to the given number of bytes while preserving
170	the contents of the buffer. If the "size" argument is omitted, the current
171	buffer size is displayed.
172
173
174	i [start [end]] ASCII memory dump
175
176	displays the buffer contents from address "start" to address "end" as ASCII
177	characters. Entering "i" without arguments is equivalent to "i .". The value
178	of "." is set to the address after the last address displayed.
179
180
181	b [start [end]] Binary memory dump
182
183	displays the buffer contents from address "start" to address "end" in a binary
184	format. Entering "b" without arguments is equivalent to "b .". The value of
185	"." is set to the address after the last address displayed.
186
187
188	m [start [end]] Hex/ASCII memory dump
189
190	displays the buffer contents from address "start" to address "end" as hex
191	words and ASCII characters. Entering "m" without arguments is equivalent to
192	"m .". The value of "." is set to the address after the last address displayed.
193
194
195	d [start [end]] Disassemble PowerPC code
196
197	disassembles the buffer contents from address "start" to address "end".
198	Entering "d" without arguments is equivalent to "d .". The value of "." is
199	set to the address after the last address displayed.
200
201
202	d65 [start [end]] Disassemble 6502 code
203
204	disassembles the buffer contents from address "start" to address "end".
205	Entering "d65" without arguments is equivalent to "d65 .". The value of
206	"." is set to the address after the last address displayed.
207
208
209	d68 [start [end]] Disassemble 680x0 code
210
211	disassembles the buffer contents from address "start" to address "end".
212	Entering "d68" without arguments is equivalent to "d68 .". The value of
213	"." is set to the address after the last address displayed.
214
215
216	d80 [start [end]] Disassemble Z80 code
217
218	disassembles the buffer contents from address "start" to address "end".
219	Entering "d80" without arguments is equivalent to "d80 .". The value of
220	"." is set to the address after the last address displayed.
221
222
223	d86 [start [end]] Disassemble 80x86 (32-bit) code
224
225	disassembles the buffer contents from address "start" to address "end".
226	Entering "d86" without arguments is equivalent to "d86 .". The value of
227	"." is set to the address after the last address displayed.
228
229
230	d8086 [start [end]] Disassemble 80x86 (16-bit) code
231
232	disassembles the buffer contents from address "start" to address "end".
233	Entering "d8086" without arguments is equivalent to "d8086 .". The value
234	of "." is set to the address after the last address displayed.
235
236
237	: start string Modify memory
238
239	puts the specified byte string at the address "start" into the buffer. The
240	value of "." is set to the address after the last address modified.
241
242
243	f start end string Fill memory
244
245	fill the buffer in the range from "start" to (and including) "end" with the
246	given byte string.
247
248
249	y[b\|h\|w] start end expr Apply expression to memory
250
251	works like the "fill" ("f") command, but it doesn't fill with a byte string
252	but with the value of an expression that is re-evaluated for each buffer
253	location to be filled. The command comes in three flavors: "y"/"yb" works on
254	bytes (8-bit), "yh" on half-words (16-bit) and "yw" on words (32-bit). The
255	value of "." is the current address to be modified, the value of ":" holds
256	the contents of this address before modification.
257
258	Examples:
259	yw 0 fff :<<8 shifts all words in the address range 0..fff to the left
260	by 8 bits (you can use this to convert bitmap data from
261	ARGB to RGBA format, for example)
262	y 0 1234 ~: inverts all bytes in the address range 0..1234
263	yh 2 ff 20000/. creates a table of the fractional parts of the reciprocals
264	of 1..7f
265
266
267	t start end dest Transfer memory
268
269	transfers the buffer contents from "start" to (and including) "end" to "dest".
270	Source and destination may overlap.
271
272
273	c start end dest Compare memory
274
275	compares the buffer contents in the range from "start" to (and including)
276	"end" with the contents at "dest". The addresses of all different bytes and
277	the total number of differences (decimal) are printed.
278
279
280	h start end string Search for byte string
281
282	searches for the given byte string in the buffer starting at "start" up to
283	(and including) "end". The addresses and the total number of occurrences are
284	displayed. The value of "." is set to the address of the first occurrence.
285
286
287	\ "command" Execute shell command
288
289	executes the given shell command which must be enclosed in quotes.
290
291
292	ls [args] List directory contents
293
294	works as the shell command "ls".
295
296
297	rm [args] Remove file(s)
298
299	works as the shell command "rm".
300
301
302	cp [args] Copy file(s)
303
304	works as the shell command "cp".
305
306
307	mv [args] Move file(s)
308
309	works as the shell command "mv".
310
311
312	cd directory Change current directory
313
314	works as the shell command "cd". The name of the directory doesn't have to be
315	enclosed in quotes.
316
317
318	o ["file"] Redirect output
319
320	When a file name is specified, all following output is redirected to this
321	file. The file name must be enclosed in quotation marks even if it contains
322	no spaces. Entering "o" without parameters closes the file and directs the
323	output into the terminal window again.
324
325
326	[ start "file" Load data from file
327
328	loads the contents of the specified file into the buffer starting from address
329	"start". The file name must be enclosed in quotation marks even if it contains
330	no spaces. The value of "." is set to the address after the last address
331	affected by the load.
332
333
334	] start size "file" Save data to file
335
336	writes "size" number of bytes of the buffer from "start" to the specified file.
337	The file name must be enclosed in quotation marks even if it contains no spaces.
338
339
340	set [var[=value]] Set/clear/show variables
341
342	If no arguments are given, all currently defined variables are displayed.
343	Otherwise, the value of "var" is set to the specified value. If "=value"
344	is omitted, the variable "var" is cleared.
345
346
347	cv Clear all variables
348
349	clears all currently defined variables.
350
351
352	Examples
353	--------
354
355	Here are some simple examples for what is possible with cxmon.
356
357	Join "file1" and "file2" to "file3":
358
359	[ 0 "file1"
360	[ . "file2"
361	] 0 . "file3"
362
363	Remove the first 24 bytes (e.g. an unneeded header) of a file:
364
365	[ 0 "file"
366	] 18 .-18 "file"
367
368	Load the cxmon executable and search for PowerPC "nop" commands:
369
370	[ 0 "cxmon"
371	h 0 . 60,00,00,00
372
373	Create a modified version of cxmon so that the prompt has " $" instead of
374	"->":
375
376	[ 0 "cxmon"
377	set size=.
378	h 0 . "->"
379	: . " $"
380	] 0 size "cxmon1"
381
382	Convert a binary file which contains 16-bit numbers in little-endian format
383	to big-endian format (or vice-versa):
384
385	[ 0 "file"
386	yh 0 .-1 :>>8\|:<<8
387	] 0 . "file"
388
389	Load a BeBox boot ROM image and start disassembling the system reset handler:
390
391	[ 0 "bootnub.image"
392	d 100
393
394
395	Using cxmon in your own programs
396	--------------------------------
397
398	cxmon provides a simple interface for integration in other programs. It can,
399	for example, be used as a monitor/debugger for an emulator (it is used in
400	Basilisk II in this way).
401
402	Here's how to do it (all functions are defined in the mon.h header file):
403
404	1. Link all the cxmon object files, except main.o, to your program.
405	2. In your program, call mon_init() before using any other cxmon functions.
406	3. After calling mon_init(), set the mon_read_byte and mon_write_byte
407	function pointers to the routines used for accessing memory.
408	4. You can use mon_add_command() to add new commands to cxmon by specifying
409	the command name, function and help text. From within your command
410	function, you can use mon_get_token() and mon_expression() to parse the
411	arguments and the mon_read/write_*() functions to access memory.
412	5. To enter cxmon, call the mon() function like this:
413
414	char *args[3] = {"mon", "-r", NULL};
415	mon(2, args);
416
417	6. If you're done with cxmon, call mon_exit().
418
419
420	History
421	-------
422
423	Please consult the file "ChangeLog" for the release history.
424
425
426	Christian Bauer
427	<Christian.Bauer@uni-mainz.de>
428
429	Marc Hellwig
430	<Marc.Hellwig@uni-mainz.de>