[p5sagit/p5-mst-13.2.git] / lib / perldb.pl

package DB;

$header = '$Header: perldb.pl,v 3.0.1.6 91/01/11 18:08:58 lwall Locked $';
#
# This file is automatically included if you do perl -d.
# It's probably not useful to include this yourself.
#
# Perl supplies the values for @line and %sub.  It effectively inserts
# a do DB'DB(<linenum>); in front of every place that can
# have a breakpoint.  It also inserts a do 'perldb.pl' before the first line.
#
# $Log:	perldb.pl,v $
# Revision 3.0.1.6  91/01/11  18:08:58  lwall
# patch42: @_ couldn't be accessed from debugger
# 
# Revision 3.0.1.5  90/11/10  01:40:26  lwall
# patch38: the debugger wouldn't stop correctly or do action routines
# 
# Revision 3.0.1.4  90/10/15  17:40:38  lwall
# patch29: added caller
# patch29: the debugger now understands packages and evals
# patch29: scripts now run at almost full speed under the debugger
# patch29: more variables are settable from debugger
# 
# Revision 3.0.1.3  90/08/09  04:00:58  lwall
# patch19: debugger now allows continuation lines
# patch19: debugger can now dump lists of variables
# patch19: debugger can now add aliases easily from prompt
# 
# Revision 3.0.1.2  90/03/12  16:39:39  lwall
# patch13: perl -d didn't format stack traces of *foo right
# patch13: perl -d wiped out scalar return values of subroutines
# 
# Revision 3.0.1.1  89/10/26  23:14:02  lwall
# patch1: RCS expanded an unintended $Header in lib/perldb.pl
# 
# Revision 3.0  89/10/18  15:19:46  lwall
# 3.0 baseline
# 
# Revision 2.0  88/06/05  00:09:45  root
# Baseline version 2.0.
# 
#

open(IN, "</dev/tty") || open(IN,  "<&STDIN");	# so we don't dingle stdin
open(OUT,">/dev/tty") || open(OUT, ">&STDOUT");	# so we don't dongle stdout
select(OUT);
$| = 1;				# for DB'OUT
select(STDOUT);
$| = 1;				# for real STDOUT
$sub = '';

$header =~ s/.Header: ([^,]+),v(\s+\S+\s+\S+).*$/$1$2/;
print OUT "\nLoading DB routines from $header\n\nEnter h for help.\n\n";

sub DB {
    &save;
    ($package, $filename, $line) = caller;
    $usercontext = '($@, $!, $[, $,, $/, $\) = @saved;' .
	"package $package;";		# this won't let them modify, alas
    local(*dbline) = "_<$filename";
    $max = $#dbline;
    if (($stop,$action) = split(/\0/,$dbline{$line})) {
	if ($stop eq '1') {
	    $signal |= 1;
	}
	else {
	    $evalarg = "\$DB'signal |= do {$stop;}"; &eval;
	    $dbline{$line} =~ s/;9($|\0)/$1/;
	}
    }
    if ($single || $trace || $signal) {
	print OUT "$package'" unless $sub =~ /'/;
	print OUT "$sub($filename:$line):\t",$dbline[$line];
	for ($i = $line + 1; $i <= $max && $dbline[$i] == 0; ++$i) {
	    last if $dbline[$i] =~ /^\s*(}|#|\n)/;
	    print OUT "$sub($filename:$i):\t",$dbline[$i];
	}
    }
    $evalarg = $action, &eval if $action;
    if ($single || $signal) {
	$evalarg = $pre, &eval if $pre;
	print OUT $#stack . " levels deep in subroutine calls!\n"
	    if $single & 4;
	$start = $line;
	while ((print OUT "  DB<", $#hist+1, "> "), $cmd=&gets) {
	    $single = 0;
	    $signal = 0;
	    $cmd eq '' && exit 0;
	    chop($cmd);
	    $cmd =~ s/\\$// && do {
		print OUT "  cont: ";
		$cmd .= &gets;
		redo;
	    };
	    $cmd =~ /^q$/ && exit 0;
	    $cmd =~ /^$/ && ($cmd = $laststep);
	    push(@hist,$cmd) if length($cmd) > 1;
	    ($i) = split(/\s+/,$cmd);
	    eval "\$cmd =~ $alias{$i}", print OUT $@ if $alias{$i};
	    $cmd =~ /^h$/ && do {
		print OUT "
T		Stack trace.
s		Single step.
n		Next, steps over subroutine calls.
r		Return from current subroutine.
c [line]	Continue; optionally inserts a one-time-only breakpoint 
		at the specified line.
<CR>		Repeat last n or s.
l min+incr	List incr+1 lines starting at min.
l min-max	List lines.
l line		List line;
l		List next window.
-		List previous window.
w line		List window around line.
l subname	List subroutine.
f filename	Switch to filename.
/pattern/	Search forwards for pattern; final / is optional.
?pattern?	Search backwards for pattern.
L		List breakpoints and actions.
S		List subroutine names.
t		Toggle trace mode.
b [line] [condition]
		Set breakpoint; line defaults to the current execution line; 
		condition breaks if it evaluates to true, defaults to \'1\'.
b subname [condition]
		Set breakpoint at first line of subroutine.
d [line]	Delete breakpoint.
D		Delete all breakpoints.
a [line] command
		Set an action to be done before the line is executed.
		Sequence is: check for breakpoint, print line if necessary,
		do action, prompt user if breakpoint or step, evaluate line.
A		Delete all actions.
V [pkg [vars]]	List some (default all) variables in package (default current).
X [vars]	Same as \"V currentpackage [vars]\".
< command	Define command before prompt.
> command	Define command after prompt.
! number	Redo command (default previous command).
! -number	Redo number\'th to last command.
H -number	Display last number commands (default all).
q or ^D		Quit.
p expr		Same as \"print DB'OUT expr\" in current package.
= [alias value]	Define a command alias, or list current aliases.
command		Execute as a perl statement in current package.

";
		next; };
	    $cmd =~ /^t$/ && do {
		$trace = !$trace;
		print OUT "Trace = ".($trace?"on":"off")."\n";
		next; };
	    $cmd =~ /^S$/ && do {
		foreach $subname (sort(keys %sub)) {
		    print OUT $subname,"\n";
		}
		next; };
	    $cmd =~ s/^X\b/V $package/;
	    $cmd =~ /^V$/ && do {
		$cmd = 'V $package'; };
	    $cmd =~ /^V\s*(\S+)\s*(.*)/ && do {
		$packname = $1;
		@vars = split(' ',$2);
		do 'dumpvar.pl' unless defined &main'dumpvar;
		if (defined &main'dumpvar) {
		    &main'dumpvar($packname,@vars);
		}
		else {
		    print DB'OUT "dumpvar.pl not available.\n";
		}
		next; };
	    $cmd =~ /^f\s*(.*)/ && do {
		$file = $1;
		if (!$file) {
		    print OUT "The old f command is now the r command.\n";
		    print OUT "The new f command switches filenames.\n";
		    next;
		}
		if (!defined $_main{'_<' . $file}) {
		    if (($try) = grep(m#^_<.*$file#, keys %_main)) {
			$file = substr($try,2);
			print "\n$file:\n";
		    }
		}
		if (!defined $_main{'_<' . $file}) {
		    print OUT "There's no code here anything matching $file.\n";
		    next;
		}
		elsif ($file ne $filename) {
		    *dbline = "_<$file";
		    $max = $#dbline;
		    $filename = $file;
		    $start = 1;
		    $cmd = "l";
		} };
	    $cmd =~ /^l\s*(['A-Za-z_]['\w]*)/ && do {
		$subname = $1;
		$subname = "main'" . $subname unless $subname =~ /'/;
		$subname = "main" . $subname if substr($subname,0,1) eq "'";
		($file,$subrange) = split(/:/,$sub{$subname});
		if ($file ne $filename) {
		    *dbline = "_<$file";
		    $max = $#dbline;
		    $filename = $file;
		}
		if ($subrange) {
		    if (eval($subrange) < -$window) {
			$subrange =~ s/-.*/+/;
		    }
		    $cmd = "l $subrange";
		} else {
		    print OUT "Subroutine $1 not found.\n";
		    next;
		} };
	    $cmd =~ /^w\s*(\d*)$/ && do {
		$incr = $window - 1;
		$start = $1 if $1;
		$start -= $preview;
		$cmd = 'l ' . $start . '-' . ($start + $incr); };
	    $cmd =~ /^-$/ && do {
		$incr = $window - 1;
		$cmd = 'l ' . ($start-$window*2) . '+'; };
	    $cmd =~ /^l$/ && do {
		$incr = $window - 1;
		$cmd = 'l ' . $start . '-' . ($start + $incr); };
	    $cmd =~ /^l\s*(\d*)\+(\d*)$/ && do {
		$start = $1 if $1;
		$incr = $2;
		$incr = $window - 1 unless $incr;
		$cmd = 'l ' . $start . '-' . ($start + $incr); };
	    $cmd =~ /^l\s*(([\d\$\.]+)([-,]([\d\$\.]+))?)?/ && do {
		$end = (!$2) ? $max : ($4 ? $4 : $2);
		$end = $max if $end > $max;
		$i = $2;
		$i = $line if $i eq '.';
		$i = 1 if $i < 1;
		for (; $i <= $end; $i++) {
		    print OUT "$i:\t", $dbline[$i];
		    last if $signal;
		}
		$start = $i;	# remember in case they want more
		$start = $max if $start > $max;
		next; };
	    $cmd =~ /^D$/ && do {
		print OUT "Deleting all breakpoints...\n";
		for ($i = 1; $i <= $max ; $i++) {
		    if (defined $dbline{$i}) {
			$dbline{$i} =~ s/^[^\0]+//;
			if ($dbline{$i} =~ s/^\0?$//) {
			    delete $dbline{$i};
			}
		    }
		}
		next; };
	    $cmd =~ /^L$/ && do {
		for ($i = 1; $i <= $max; $i++) {
		    if (defined $dbline{$i}) {
			print OUT "$i:\t", $dbline[$i];
			($stop,$action) = split(/\0/, $dbline{$i});
			print OUT "  break if (", $stop, ")\n" 
			    if $stop;
			print OUT "  action:  ", $action, "\n" 
			    if $action;
			last if $signal;
		    }
		}
		next; };
	    $cmd =~ /^b\s*(['A-Za-z_]['\w]*)\s*(.*)/ && do {
		$subname = $1;
		$cond = $2 || '1';
		$subname = "$package'" . $subname unless $subname =~ /'/;
		$subname = "main" . $subname if substr($subname,0,1) eq "'";
		($filename,$i) = split(/[:-]/, $sub{$subname});
		if ($i) {
		    *dbline = "_<$filename";
		    ++$i while $dbline[$i] == 0 && $i < $#dbline;
		    $dbline{$i} =~ s/^[^\0]*/$cond/;
		} else {
		    print OUT "Subroutine $subname not found.\n";
		}
		next; };
	    $cmd =~ /^b\s*(\d*)\s*(.*)/ && do {
		$i = ($1?$1:$line);
		$cond = $2 || '1';
		if ($dbline[$i] == 0) {
		    print OUT "Line $i not breakable.\n";
		} else {
		    $dbline{$i} =~ s/^[^\0]*/$cond/;
		}
		next; };
	    $cmd =~ /^d\s*(\d+)?/ && do {
		$i = ($1?$1:$line);
		$dbline{$i} =~ s/^[^\0]*//;
		delete $dbline{$i} if $dbline{$i} eq '';
		next; };
	    $cmd =~ /^A$/ && do {
		for ($i = 1; $i <= $max ; $i++) {
		    if (defined $dbline{$i}) {
			$dbline{$i} =~ s/\0[^\0]*//;
			delete $dbline{$i} if $dbline{$i} eq '';
		    }
		}
		next; };
	    $cmd =~ /^<\s*(.*)/ && do {
		$pre = do action($1);
		next; };
	    $cmd =~ /^>\s*(.*)/ && do {
		$post = do action($1);
		next; };
	    $cmd =~ /^a\s*(\d+)(\s+(.*))?/ && do {
		$i = $1;
		if ($dbline[$i] == 0) {
		    print OUT "Line $i may not have an action.\n";
		} else {
		    $dbline{$i} =~ s/\0[^\0]*//;
		    $dbline{$i} .= "\0" . do action($3);
		}
		next; };
	    $cmd =~ /^n$/ && do {
		$single = 2;
		$laststep = $cmd;
		last; };
	    $cmd =~ /^s$/ && do {
		$single = 1;
		$laststep = $cmd;
		last; };
	    $cmd =~ /^c\s*(\d*)\s*$/ && do {
		$i = $1;
		if ($i) {
		    if ($dbline[$i] == 0) {
		        print OUT "Line $i not breakable.\n";
			next;
		    }
		    $dbline{$i} =~ s/(\0|$)/;9$1/;	# add one-time-only b.p.
		}
		for ($i=0; $i <= $#stack; ) {
		    $stack[$i++] &= ~1;
		}
		last; };
	    $cmd =~ /^r$/ && do {
		$stack[$#stack] |= 2;
		last; };
	    $cmd =~ /^T$/ && do {
		local($p,$f,$l,$s,$h,$a,@a,@sub);
		for ($i = 1; ($p,$f,$l,$s,$h,$w) = caller($i); $i++) {
		    @a = @args;
		    for (@a) {
			if (/^StB\000/ && length($_) == length($_main{'_main'})) {
			    $_ = sprintf("%s",$_);
			}
			else {
			    s/'/\\'/g;
			    s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/;
			    s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
			    s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
			}
		    }
		    $w = $w ? '@ = ' : '$ = ';
		    $a = $h ? '(' . join(', ', @a) . ')' : '';
		    push(@sub, "$w&$s$a from file $f line $l\n");
		    last if $signal;
		}
		for ($i=0; $i <= $#sub; $i++) {
		    last if $signal;
		    print OUT $sub[$i];
		}
	        next; };
	    $cmd =~ /^\/(.*)$/ && do {
		$inpat = $1;
		$inpat =~ s:([^\\])/$:$1:;
		if ($inpat ne "") {
		    eval '$inpat =~ m'."\n$inpat\n";	
		    if ($@ ne "") {
		    	print OUT "$@";
		    	next;
		    }
		    $pat = $inpat;
		}
		$end = $start;
		eval '
		for (;;) {
		    ++$start;
		    $start = 1 if ($start > $max);
		    last if ($start == $end);
		    if ($dbline[$start] =~ m'."\n$pat\n".'i) {
			print OUT "$start:\t", $dbline[$start], "\n";
			last;
		    }
		} ';
		print OUT "/$pat/: not found\n" if ($start == $end);
		next; };
	    $cmd =~ /^\?(.*)$/ && do {
		$inpat = $1;
		$inpat =~ s:([^\\])\?$:$1:;
		if ($inpat ne "") {
		    eval '$inpat =~ m'."\n$inpat\n";	
		    if ($@ ne "") {
		    	print OUT "$@";
		    	next;
		    }
		    $pat = $inpat;
		}
		$end = $start;
		eval '
		for (;;) {
		    --$start;
		    $start = $max if ($start <= 0);
		    last if ($start == $end);
		    if ($dbline[$start] =~ m'."\n$pat\n".'i) {
			print OUT "$start:\t", $dbline[$start], "\n";
			last;
		    }
		} ';
		print OUT "?$pat?: not found\n" if ($start == $end);
		next; };
	    $cmd =~ /^!+\s*(-)?(\d+)?$/ && do {
		pop(@hist) if length($cmd) > 1;
		$i = ($1?($#hist-($2?$2:1)):($2?$2:$#hist));
		$cmd = $hist[$i] . "\n";
		print OUT $cmd;
		redo; };
	    $cmd =~ /^!(.+)$/ && do {
		$pat = "^$1";
		pop(@hist) if length($cmd) > 1;
		for ($i = $#hist; $i; --$i) {
		    last if $hist[$i] =~ $pat;
		}
		if (!$i) {
		    print OUT "No such command!\n\n";
		    next;
		}
		$cmd = $hist[$i] . "\n";
		print OUT $cmd;
		redo; };
	    $cmd =~ /^H\s*(-(\d+))?/ && do {
		$end = $2?($#hist-$2):0;
		$hist = 0 if $hist < 0;
		for ($i=$#hist; $i>$end; $i--) {
		    print OUT "$i: ",$hist[$i],"\n"
			unless $hist[$i] =~ /^.?$/;
		};
		next; };
	    $cmd =~ s/^p( .*)?$/print DB'OUT$1/;
	    $cmd =~ /^=/ && do {
		if (local($k,$v) = ($cmd =~ /^=\s*(\S+)\s+(.*)/)) {
		    $alias{$k}="s~$k~$v~";
		    print OUT "$k = $v\n";
		} elsif ($cmd =~ /^=\s*$/) {
		    foreach $k (sort keys(%alias)) {
			if (($v = $alias{$k}) =~ s~^s\~$k\~(.*)\~$~$1~) {
			    print OUT "$k = $v\n";
			} else {
			    print OUT "$k\t$alias{$k}\n";
			};
		    };
		};
		next; };
	    $evalarg = $cmd; &eval;
	    print OUT "\n";
	}
	if ($post) {
	    $evalarg = $post; &eval;
	}
    }
    ($@, $!, $[, $,, $/, $\) = @saved;
}

sub save {
    @saved = ($@, $!, $[, $,, $/, $\);
    $[ = 0; $, = ""; $/ = "\n"; $\ = "";
}

# The following takes its argument via $evalarg to preserve current @_

sub eval {
    eval "$usercontext $evalarg; &DB'save";
    print OUT $@;
}

sub action {
    local($action) = @_;
    while ($action =~ s/\\$//) {
	print OUT "+ ";
	$action .= &gets;
    }
    $action;
}

sub gets {
    local($.);
    <IN>;
}

sub catch {
    $signal = 1;
}

sub sub {
    push(@stack, $single);
    $single &= 1;
    $single |= 4 if $#stack == $deep;
    if (wantarray) {
	@i = &$sub;
	$single |= pop(@stack);
	@i;
    }
    else {
	$i = &$sub;
	$single |= pop(@stack);
	$i;
    }
}

$single = 1;			# so it stops on first executable statement
@hist = ('?');
$SIG{'INT'} = "DB'catch";
$deep = 100;		# warning if stack gets this deep
$window = 10;
$preview = 3;

@stack = (0);
@ARGS = @ARGV;
for (@args) {
    s/'/\\'/g;
    s/(.*)/'$1'/ unless /^-?[\d.]+$/;
}

if (-f '.perldb') {
    do './.perldb';
}
elsif (-f "$ENV{'LOGDIR'}/.perldb") {
    do "$ENV{'LOGDIR'}/.perldb";
}
elsif (-f "$ENV{'HOME'}/.perldb") {
    do "$ENV{'HOME'}/.perldb";
}

1;
Commit	Line	Data
a687059c	1	package DB;
a687059c	2
27e2fb84	3	$header = '$Header: perldb.pl,v 3.0.1.6 91/01/11 18:08:58 lwall Locked $';
a687059c	4	#
	5	# This file is automatically included if you do perl -d.
	6	# It's probably not useful to include this yourself.
	7	#
	8	# Perl supplies the values for @line and %sub. It effectively inserts
	9	# a do DB'DB(<linenum>); in front of every place that can
	10	# have a breakpoint. It also inserts a do 'perldb.pl' before the first line.
	11	#
	12	# $Log: perldb.pl,v $
27e2fb84	13	# Revision 3.0.1.6 91/01/11 18:08:58 lwall
	14	# patch42: @_ couldn't be accessed from debugger
	15	#
34de22dd	16	# Revision 3.0.1.5 90/11/10 01:40:26 lwall
	17	# patch38: the debugger wouldn't stop correctly or do action routines
	18	#
76854fea	19	# Revision 3.0.1.4 90/10/15 17:40:38 lwall
	20	# patch29: added caller
	21	# patch29: the debugger now understands packages and evals
	22	# patch29: scripts now run at almost full speed under the debugger
	23	# patch29: more variables are settable from debugger
	24	#
33b78306	25	# Revision 3.0.1.3 90/08/09 04:00:58 lwall
	26	# patch19: debugger now allows continuation lines
	27	# patch19: debugger can now dump lists of variables
	28	# patch19: debugger can now add aliases easily from prompt
	29	#
79a0689e	30	# Revision 3.0.1.2 90/03/12 16:39:39 lwall
	31	# patch13: perl -d didn't format stack traces of *foo right
	32	# patch13: perl -d wiped out scalar return values of subroutines
	33	#
03a14243	34	# Revision 3.0.1.1 89/10/26 23:14:02 lwall
	35	# patch1: RCS expanded an unintended $Header in lib/perldb.pl
	36	#
a687059c	37	# Revision 3.0 89/10/18 15:19:46 lwall
	38	# 3.0 baseline
	39	#
	40	# Revision 2.0 88/06/05 00:09:45 root
	41	# Baseline version 2.0.
	42	#
	43	#
	44
76854fea	45	open(IN, "</dev/tty") \|\| open(IN, "<&STDIN"); # so we don't dingle stdin
76854fea	46	open(OUT,">/dev/tty") \|\| open(OUT, ">&STDOUT"); # so we don't dongle stdout
a687059c	47	select(OUT);
	48	$\| = 1; # for DB'OUT
	49	select(STDOUT);
	50	$\| = 1; # for real STDOUT
76854fea	51	$sub = '';
a687059c	52
03a14243	53	$header =~ s/.Header: ([^,]+),v(\s+\S+\s+\S+).*$/$1$2/;
76854fea	54	print OUT "\nLoading DB routines from $header\n\nEnter h for help.\n\n";
a687059c	55
a687059c	56	sub DB {
76854fea	57	&save;
	58	($package, $filename, $line) = caller;
	59	$usercontext = '($@, $!, $[, $,, $/, $\) = @saved;' .
	60	"package $package;"; # this won't let them modify, alas
	61	local(*dbline) = "_<$filename";
	62	$max = $#dbline;
	63	if (($stop,$action) = split(/\0/,$dbline{$line})) {
a687059c	64	if ($stop eq '1') {
	65	$signal \|= 1;
	66	}
	67	else {
27e2fb84	68	$evalarg = "\$DB'signal \|= do {$stop;}"; &eval;
76854fea	69	$dbline{$line} =~ s/;9($\|\0)/$1/;
a687059c	70	}
	71	}
	72	if ($single \|\| $trace \|\| $signal) {
76854fea	73	print OUT "$package'" unless $sub =~ /'/;
	74	print OUT "$sub($filename:$line):\t",$dbline[$line];
	75	for ($i = $line + 1; $i <= $max && $dbline[$i] == 0; ++$i) {
	76	last if $dbline[$i] =~ /^\s*(}\|#\|\n)/;
	77	print OUT "$sub($filename:$i):\t",$dbline[$i];
a687059c	78	}
a687059c	79	}
27e2fb84	80	$evalarg = $action, &eval if $action;
a687059c	81	if ($single \|\| $signal) {
27e2fb84	82	$evalarg = $pre, &eval if $pre;
a687059c	83	print OUT $#stack . " levels deep in subroutine calls!\n"
	84	if $single & 4;
	85	$start = $line;
76854fea	86	while ((print OUT " DB<", $#hist+1, "> "), $cmd=&gets) {
a687059c	87	$single = 0;
	88	$signal = 0;
	89	$cmd eq '' && exit 0;
	90	chop($cmd);
33b78306	91	$cmd =~ s/\\$// && do {
33b78306	92	print OUT " cont: ";
76854fea	93	$cmd .= &gets;
33b78306	94	redo;
33b78306	95	};
a687059c	96	$cmd =~ /^q$/ && exit 0;
	97	$cmd =~ /^$/ && ($cmd = $laststep);
	98	push(@hist,$cmd) if length($cmd) > 1;
	99	($i) = split(/\s+/,$cmd);
	100	eval "\$cmd =~ $alias{$i}", print OUT $@ if $alias{$i};
	101	$cmd =~ /^h$/ && do {
	102	print OUT "
	103	T Stack trace.
	104	s Single step.
	105	n Next, steps over subroutine calls.
76854fea	106	r Return from current subroutine.
a687059c	107	c [line] Continue; optionally inserts a one-time-only breakpoint
	108	at the specified line.
	109	<CR> Repeat last n or s.
	110	l min+incr List incr+1 lines starting at min.
	111	l min-max List lines.
	112	l line List line;
	113	l List next window.
	114	- List previous window.
	115	w line List window around line.
	116	l subname List subroutine.
76854fea	117	f filename Switch to filename.
a687059c	118	/pattern/ Search forwards for pattern; final / is optional.
	119	?pattern? Search backwards for pattern.
	120	L List breakpoints and actions.
	121	S List subroutine names.
	122	t Toggle trace mode.
	123	b [line] [condition]
	124	Set breakpoint; line defaults to the current execution line;
	125	condition breaks if it evaluates to true, defaults to \'1\'.
	126	b subname [condition]
	127	Set breakpoint at first line of subroutine.
	128	d [line] Delete breakpoint.
	129	D Delete all breakpoints.
	130	a [line] command
	131	Set an action to be done before the line is executed.
	132	Sequence is: check for breakpoint, print line if necessary,
	133	do action, prompt user if breakpoint or step, evaluate line.
	134	A Delete all actions.
76854fea	135	V [pkg [vars]] List some (default all) variables in package (default current).
76854fea	136	X [vars] Same as \"V currentpackage [vars]\".
a687059c	137	< command Define command before prompt.
	138	> command Define command after prompt.
	139	! number Redo command (default previous command).
	140	! -number Redo number\'th to last command.
	141	H -number Display last number commands (default all).
	142	q or ^D Quit.
76854fea	143	p expr Same as \"print DB'OUT expr\" in current package.
33b78306	144	= [alias value] Define a command alias, or list current aliases.
76854fea	145	command Execute as a perl statement in current package.
a687059c	146
	147	";
	148	next; };
	149	$cmd =~ /^t$/ && do {
	150	$trace = !$trace;
	151	print OUT "Trace = ".($trace?"on":"off")."\n";
	152	next; };
	153	$cmd =~ /^S$/ && do {
	154	foreach $subname (sort(keys %sub)) {
76854fea	155	print OUT $subname,"\n";
a687059c	156	}
a687059c	157	next; };
76854fea	158	$cmd =~ s/^X\b/V $package/;
a687059c	159	$cmd =~ /^V$/ && do {
76854fea	160	$cmd = 'V $package'; };
76854fea	161	$cmd =~ /^V\s(\S+)\s(.*)/ && do {
a687059c	162	$packname = $1;
33b78306	163	@vars = split(' ',$2);
a687059c	164	do 'dumpvar.pl' unless defined &main'dumpvar;
a687059c	165	if (defined &main'dumpvar) {
33b78306	166	&main'dumpvar($packname,@vars);
a687059c	167	}
	168	else {
	169	print DB'OUT "dumpvar.pl not available.\n";
	170	}
	171	next; };
76854fea	172	$cmd =~ /^f\s(.)/ && do {
	173	$file = $1;
	174	if (!$file) {
	175	print OUT "The old f command is now the r command.\n";
	176	print OUT "The new f command switches filenames.\n";
	177	next;
	178	}
	179	if (!defined $_main{'_<' . $file}) {
	180	if (($try) = grep(m#^_<.*$file#, keys %_main)) {
	181	$file = substr($try,2);
	182	print "\n$file:\n";
	183	}
	184	}
	185	if (!defined $_main{'_<' . $file}) {
	186	print OUT "There's no code here anything matching $file.\n";
	187	next;
	188	}
	189	elsif ($file ne $filename) {
	190	*dbline = "_<$file";
	191	$max = $#dbline;
	192	$filename = $file;
	193	$start = 1;
	194	$cmd = "l";
	195	} };
a687059c	196	$cmd =~ /^l\s(['A-Za-z_]['\w])/ && do {
	197	$subname = $1;
	198	$subname = "main'" . $subname unless $subname =~ /'/;
76854fea	199	$subname = "main" . $subname if substr($subname,0,1) eq "'";
	200	($file,$subrange) = split(/:/,$sub{$subname});
	201	if ($file ne $filename) {
	202	*dbline = "_<$file";
	203	$max = $#dbline;
	204	$filename = $file;
	205	}
a687059c	206	if ($subrange) {
	207	if (eval($subrange) < -$window) {
	208	$subrange =~ s/-.*/+/;
	209	}
	210	$cmd = "l $subrange";
	211	} else {
	212	print OUT "Subroutine $1 not found.\n";
	213	next;
	214	} };
	215	$cmd =~ /^w\s(\d)$/ && do {
	216	$incr = $window - 1;
	217	$start = $1 if $1;
	218	$start -= $preview;
	219	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	220	$cmd =~ /^-$/ && do {
	221	$incr = $window - 1;
	222	$cmd = 'l ' . ($start-$window*2) . '+'; };
	223	$cmd =~ /^l$/ && do {
	224	$incr = $window - 1;
	225	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	226	$cmd =~ /^l\s(\d)\+(\d*)$/ && do {
	227	$start = $1 if $1;
	228	$incr = $2;
	229	$incr = $window - 1 unless $incr;
	230	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	231	$cmd =~ /^l\s*(([\d\$\.]+)([-,]([\d\$\.]+))?)?/ && do {
	232	$end = (!$2) ? $max : ($4 ? $4 : $2);
	233	$end = $max if $end > $max;
	234	$i = $2;
	235	$i = $line if $i eq '.';
	236	$i = 1 if $i < 1;
	237	for (; $i <= $end; $i++) {
76854fea	238	print OUT "$i:\t", $dbline[$i];
a687059c	239	last if $signal;
	240	}
	241	$start = $i; # remember in case they want more
	242	$start = $max if $start > $max;
	243	next; };
	244	$cmd =~ /^D$/ && do {
	245	print OUT "Deleting all breakpoints...\n";
	246	for ($i = 1; $i <= $max ; $i++) {
76854fea	247	if (defined $dbline{$i}) {
	248	$dbline{$i} =~ s/^[^\0]+//;
	249	if ($dbline{$i} =~ s/^\0?$//) {
	250	delete $dbline{$i};
	251	}
	252	}
a687059c	253	}
	254	next; };
	255	$cmd =~ /^L$/ && do {
	256	for ($i = 1; $i <= $max; $i++) {
76854fea	257	if (defined $dbline{$i}) {
	258	print OUT "$i:\t", $dbline[$i];
	259	($stop,$action) = split(/\0/, $dbline{$i});
	260	print OUT " break if (", $stop, ")\n"
	261	if $stop;
	262	print OUT " action: ", $action, "\n"
	263	if $action;
a687059c	264	last if $signal;
	265	}
	266	}
	267	next; };
	268	$cmd =~ /^b\s(['A-Za-z_]['\w])\s(.)/ && do {
	269	$subname = $1;
76854fea	270	$cond = $2 \|\| '1';
	271	$subname = "$package'" . $subname unless $subname =~ /'/;
	272	$subname = "main" . $subname if substr($subname,0,1) eq "'";
	273	($filename,$i) = split(/[:-]/, $sub{$subname});
a687059c	274	if ($i) {
76854fea	275	*dbline = "_<$filename";
	276	++$i while $dbline[$i] == 0 && $i < $#dbline;
	277	$dbline{$i} =~ s/^[^\0]*/$cond/;
a687059c	278	} else {
76854fea	279	print OUT "Subroutine $subname not found.\n";
a687059c	280	}
	281	next; };
	282	$cmd =~ /^b\s(\d)\s(.)/ && do {
	283	$i = ($1?$1:$line);
76854fea	284	$cond = $2 \|\| '1';
76854fea	285	if ($dbline[$i] == 0) {
a687059c	286	print OUT "Line $i not breakable.\n";
a687059c	287	} else {
76854fea	288	$dbline{$i} =~ s/^[^\0]*/$cond/;
a687059c	289	}
	290	next; };
	291	$cmd =~ /^d\s*(\d+)?/ && do {
	292	$i = ($1?$1:$line);
76854fea	293	$dbline{$i} =~ s/^[^\0]*//;
76854fea	294	delete $dbline{$i} if $dbline{$i} eq '';
a687059c	295	next; };
	296	$cmd =~ /^A$/ && do {
	297	for ($i = 1; $i <= $max ; $i++) {
76854fea	298	if (defined $dbline{$i}) {
	299	$dbline{$i} =~ s/\0[^\0]*//;
	300	delete $dbline{$i} if $dbline{$i} eq '';
	301	}
a687059c	302	}
	303	next; };
	304	$cmd =~ /^<\s(.)/ && do {
	305	$pre = do action($1);
	306	next; };
	307	$cmd =~ /^>\s(.)/ && do {
	308	$post = do action($1);
	309	next; };
	310	$cmd =~ /^a\s(\d+)(\s+(.))?/ && do {
	311	$i = $1;
76854fea	312	if ($dbline[$i] == 0) {
a687059c	313	print OUT "Line $i may not have an action.\n";
a687059c	314	} else {
76854fea	315	$dbline{$i} =~ s/\0[^\0]*//;
34de22dd	316	$dbline{$i} .= "\0" . do action($3);
a687059c	317	}
	318	next; };
	319	$cmd =~ /^n$/ && do {
	320	$single = 2;
	321	$laststep = $cmd;
	322	last; };
	323	$cmd =~ /^s$/ && do {
	324	$single = 1;
	325	$laststep = $cmd;
	326	last; };
	327	$cmd =~ /^c\s(\d)\s*$/ && do {
	328	$i = $1;
	329	if ($i) {
76854fea	330	if ($dbline[$i] == 0) {
a687059c	331	print OUT "Line $i not breakable.\n";
	332	next;
	333	}
76854fea	334	$dbline{$i} =~ s/(\0\|$)/;9$1/; # add one-time-only b.p.
a687059c	335	}
	336	for ($i=0; $i <= $#stack; ) {
	337	$stack[$i++] &= ~1;
	338	}
	339	last; };
76854fea	340	$cmd =~ /^r$/ && do {
a687059c	341	$stack[$#stack] \|= 2;
	342	last; };
	343	$cmd =~ /^T$/ && do {
76854fea	344	local($p,$f,$l,$s,$h,$a,@a,@sub);
	345	for ($i = 1; ($p,$f,$l,$s,$h,$w) = caller($i); $i++) {
	346	@a = @args;
	347	for (@a) {
	348	if (/^StB\000/ && length($_) == length($_main{'_main'})) {
	349	$_ = sprintf("%s",$_);
	350	}
	351	else {
	352	s/'/\\'/g;
	353	s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/;
	354	s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
	355	s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
	356	}
	357	}
	358	$w = $w ? '@ = ' : '$ = ';
	359	$a = $h ? '(' . join(', ', @a) . ')' : '';
	360	push(@sub, "$w&$s$a from file $f line $l\n");
	361	last if $signal;
	362	}
	363	for ($i=0; $i <= $#sub; $i++) {
a687059c	364	last if $signal;
76854fea	365	print OUT $sub[$i];
a687059c	366	}
	367	next; };
	368	$cmd =~ /^\/(.*)$/ && do {
	369	$inpat = $1;
	370	$inpat =~ s:([^\\])/$:$1:;
	371	if ($inpat ne "") {
	372	eval '$inpat =~ m'."\n$inpat\n";
	373	if ($@ ne "") {
	374	print OUT "$@";
	375	next;
	376	}
	377	$pat = $inpat;
	378	}
	379	$end = $start;
	380	eval '
	381	for (;;) {
	382	++$start;
	383	$start = 1 if ($start > $max);
	384	last if ($start == $end);
76854fea	385	if ($dbline[$start] =~ m'."\n$pat\n".'i) {
76854fea	386	print OUT "$start:\t", $dbline[$start], "\n";
a687059c	387	last;
	388	}
	389	} ';
	390	print OUT "/$pat/: not found\n" if ($start == $end);
	391	next; };
	392	$cmd =~ /^\?(.*)$/ && do {
	393	$inpat = $1;
	394	$inpat =~ s:([^\\])\?$:$1:;
	395	if ($inpat ne "") {
	396	eval '$inpat =~ m'."\n$inpat\n";
	397	if ($@ ne "") {
	398	print OUT "$@";
	399	next;
	400	}
	401	$pat = $inpat;
	402	}
	403	$end = $start;
	404	eval '
	405	for (;;) {
	406	--$start;
	407	$start = $max if ($start <= 0);
	408	last if ($start == $end);
76854fea	409	if ($dbline[$start] =~ m'."\n$pat\n".'i) {
76854fea	410	print OUT "$start:\t", $dbline[$start], "\n";
a687059c	411	last;
	412	}
	413	} ';
	414	print OUT "?$pat?: not found\n" if ($start == $end);
	415	next; };
	416	$cmd =~ /^!+\s*(-)?(\d+)?$/ && do {
	417	pop(@hist) if length($cmd) > 1;
	418	$i = ($1?($#hist-($2?$2:1)):($2?$2:$#hist));
	419	$cmd = $hist[$i] . "\n";
	420	print OUT $cmd;
	421	redo; };
	422	$cmd =~ /^!(.+)$/ && do {
	423	$pat = "^$1";
	424	pop(@hist) if length($cmd) > 1;
	425	for ($i = $#hist; $i; --$i) {
	426	last if $hist[$i] =~ $pat;
	427	}
	428	if (!$i) {
	429	print OUT "No such command!\n\n";
	430	next;
	431	}
	432	$cmd = $hist[$i] . "\n";
	433	print OUT $cmd;
	434	redo; };
	435	$cmd =~ /^H\s*(-(\d+))?/ && do {
	436	$end = $2?($#hist-$2):0;
	437	$hist = 0 if $hist < 0;
	438	for ($i=$#hist; $i>$end; $i--) {
	439	print OUT "$i: ",$hist[$i],"\n"
	440	unless $hist[$i] =~ /^.?$/;
	441	};
	442	next; };
	443	$cmd =~ s/^p( .*)?$/print DB'OUT$1/;
33b78306	444	$cmd =~ /^=/ && do {
	445	if (local($k,$v) = ($cmd =~ /^=\s(\S+)\s+(.)/)) {
	446	$alias{$k}="s~$k~$v~";
	447	print OUT "$k = $v\n";
	448	} elsif ($cmd =~ /^=\s*$/) {
	449	foreach $k (sort keys(%alias)) {
	450	if (($v = $alias{$k}) =~ s~^s\~$k\~(.*)\~$~$1~) {
	451	print OUT "$k = $v\n";
	452	} else {
	453	print OUT "$k\t$alias{$k}\n";
	454	};
	455	};
	456	};
	457	next; };
27e2fb84	458	$evalarg = $cmd; &eval;
76854fea	459	print OUT "\n";
a687059c	460	}
a687059c	461	if ($post) {
27e2fb84	462	$evalarg = $post; &eval;
a687059c	463	}
a687059c	464	}
76854fea	465	($@, $!, $[, $,, $/, $\) = @saved;
	466	}
	467
	468	sub save {
	469	@saved = ($@, $!, $[, $,, $/, $\);
	470	$[ = 0; $, = ""; $/ = "\n"; $\ = "";
	471	}
	472
27e2fb84	473	# The following takes its argument via $evalarg to preserve current @_
27e2fb84	474
76854fea	475	sub eval {
27e2fb84	476	eval "$usercontext $evalarg; &DB'save";
76854fea	477	print OUT $@;
a687059c	478	}
	479
	480	sub action {
	481	local($action) = @_;
	482	while ($action =~ s/\\$//) {
	483	print OUT "+ ";
76854fea	484	$action .= &gets;
a687059c	485	}
	486	$action;
	487	}
	488
76854fea	489	sub gets {
	490	local($.);
	491	<IN>;
	492	}
	493
a687059c	494	sub catch {
	495	$signal = 1;
	496	}
	497
	498	sub sub {
	499	push(@stack, $single);
	500	$single &= 1;
	501	$single \|= 4 if $#stack == $deep;
a687059c	502	if (wantarray) {
a687059c	503	@i = &$sub;
79a0689e	504	$single \|= pop(@stack);
79a0689e	505	@i;
a687059c	506	}
	507	else {
	508	$i = &$sub;
79a0689e	509	$single \|= pop(@stack);
79a0689e	510	$i;
a687059c	511	}
a687059c	512	}
	513
	514	$single = 1; # so it stops on first executable statement
a687059c	515	@hist = ('?');
	516	$SIG{'INT'} = "DB'catch";
	517	$deep = 100; # warning if stack gets this deep
	518	$window = 10;
	519	$preview = 3;
	520
	521	@stack = (0);
76854fea	522	@ARGS = @ARGV;
a687059c	523	for (@args) {
	524	s/'/\\'/g;
	525	s/(.*)/'$1'/ unless /^-?[\d.]+$/;
	526	}
a687059c	527
	528	if (-f '.perldb') {
	529	do './.perldb';
	530	}
	531	elsif (-f "$ENV{'LOGDIR'}/.perldb") {
	532	do "$ENV{'LOGDIR'}/.perldb";
	533	}
	534	elsif (-f "$ENV{'HOME'}/.perldb") {
	535	do "$ENV{'HOME'}/.perldb";
	536	}
	537
	538	1;