oadldb - OADL Manual Page

NAME

oadldb - OADL binary debugger

SYNOPSIS

oadldb [flags] [filename]

The [flags] are zero or more of:

-m size: initial size of the heap (default 1MB)
-ah thresh: sets array heap-vs-malloc threshold
-t: generate instruction traces during execution
-lLIB: loads libLIB.oax from the OADL library path
-Ldir: adds dir to the library search path

The [filename] is an executable file (with a suffix of ".oax").

DESCRIPTION

oadldb is a console-mode debugger for executable oadl programs (compiled by oadlc into .oax files).

Available commands

oadldb inherits a lot of design philosophy from gdb; as such, many of the following commands may be familiar. Note that oadldb has extensive online help; more information about each command may be obtained by typing "help <command>".

Cmd	Alt	Description
b	break	set a breakpoint
tbreak		set a temporary breakpoint
w	watch	set an expression watchpoint
d	disable	disable breakpoints
e	enable	enable breakpoints
delete		delete breakpoints by number
clear		delete breakpoints by location
info		get info about breakpoints
r	run	run the OADL program
c	continue	continue execution
until		continue execution until a specified line
restart		restarts the program
j	jump	jumps to a specific location
s	step	single step
n	next	single step, stepping over procedure calls
si	stepi	single step an instruction
ni	nexti	single step an instruction, stepping into CALLs
finish		complete execution of function at current stack frame
return		return immediately from function at current stack frame
bt	backtrace	prints a stack backtrace
up		move up in the stack frames (toward stack base)
down		move down in the stack frames (toward top of stack)
f	frame	change or print info about stack frames
q	quit	exit the debugger
l	list	display program source and/or disassembly
set		set a variable to an evaluated expression
p	print	print the value of an expression
dprint		deferred print of the value of an expression
t	throw	throw an exception
v	var	declare (and optionally intialize) a new global variable
<cr>	again	repeat the last command
env		set debugging environment parameters
h	help	prints help. Topics include: breakpoints locations stack <command>

Breakpoints

The OADL debugger has several commands which handle breakpoints. These include:

breakpoint location	set a breakpoint
breakpoint location if expr	set a conditional breakpoint
watch expr	set an expression watchpoint
disable opt-breakpoints	disable some breakpoints
enable opt-breakpoints	enable some breakpoints
delete opt-breakpoints	delete some breakpoints by number
clear opt-location	delete breakpoints at some location
info opt-breakpoints	print a table of breakpoints

The opt-breakpoints is a list of zero or more breakpoint numbers. It may contain ranges, such as "3 - 5". It may also be the character "*", which is interpreted as "all". The "*" may be followed by a "-" and then a list of numbers, which is interpreted as "all but these breakpoints." For example, "disable * - 3" disables every breakpoint except for breakpoint number 3.

Code locations

OADL code locations are specified in one of several ways:

They may be the name of an OADL function; for example:
b fooFunc
They may be an expression that evaluates to an OADL function; for example:
b obj.create
b procArray[5]
They may be a function / code address combination; for example:
b fooFunc@15
b obj.create@13
They may be a code address in the current function; for example:
b @29
They may be a filename:linenum combination; for example:
b foo.oad:37
They may be a just a line number in the current file; for example:
b 76

If no location is given, the currently executing line of the OADL program is assumed. If a reference to a line with no code is given, the location will be recalculated as the location of the next valid line. Similarly, if an instruction address contained within a multi- byte instruction is given, the location will be recalculated as the address of the next instruction in the function.

If a file's directory path is not given, any source file whose name matches the given location may resolve the location. If multiple source files have the same base name, unpredictable results will occur.

EXAMPLE

    bash $ oadlc foo.oad -o foo.oax
    bash $ oadldb foo.oax
    db> b main
    Breakpoint #0 main
    db> run
    Hit breakpoint #0 main
    -> 1        proc main()
       2        {
       3            var a = 3->iterate();
       4            "", a, '\n';
    db> next
    3               var a = 3->iterate();
    db> print a
    0 1 2
    db> help continue
    continue
    c
        Continue program execution after an interruption.

    continue <ignore-count>
        Continue program execution, ignoring breakpoints at the current
        program location for <ignore-count> times.
    db> quit
    bash $