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

package DB;

$header = '$RCSfile: perldb.pl,v $$Revision: 4.0.1.1 $$Date: 91/06/07 11:17:44 $';
#
# 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 4.0.1.1  91/06/07  11:17:44  lwall
# patch4: added $^P variable to control calling of perldb routines
# patch4: debugger sometimes listed wrong number of lines for a statement
# 
# Revision 4.0  91/03/20  01:25:50  lwall
# 4.0 baseline.
# 
# 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 $package;";		# this won't let them modify, alas
    local($^P) = 0;			# don't debug our own evals
    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;
      CMD:
	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;
		};
		$cmd =~ /^q$/ && 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; };
		$cmd =~ /^t$/ && do {
		    $trace = !$trace;
		    print OUT "Trace = ".($trace?"on":"off")."\n";
		    next CMD; };
		$cmd =~ /^S$/ && do {
		    foreach $subname (sort(keys %sub)) {
			print OUT $subname,"\n";
		    }
		    next CMD; };
		$cmd =~ s/^X\b/V $package/;
		$cmd =~ /^V$/ && do {
		    $cmd = 'V $package'; };
		$cmd =~ /^V\b\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; };
		$cmd =~ /^f\b\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 CMD;
		    }
		    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 $file.\n";
			next CMD;
		    }
		    elsif ($file ne $filename) {
			*dbline = "_<$file";
			$max = $#dbline;
			$filename = $file;
			$start = 1;
			$cmd = "l";
		    } };
		$cmd =~ /^l\b\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;
		    } };
		$cmd =~ /^w\b\s*(\d*)$/ && 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); };
		$cmd =~ /^l\b\s*(\d*)\+(\d*)$/ && do {
		    $start = $1 if $1;
		    $incr = $2;
		    $incr = $window - 1 unless $incr;
		    $cmd = 'l ' . $start . '-' . ($start + $incr); };
		$cmd =~ /^l\b\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; };
		$cmd =~ /^D$/ && 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; };
		$cmd =~ /^L$/ && 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; };
		$cmd =~ /^b\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; };
		$cmd =~ /^b\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; };
		$cmd =~ /^d\b\s*(\d+)?/ && do {
		    $i = ($1?$1:$line);
		    $dbline{$i} =~ s/^[^\0]*//;
		    delete $dbline{$i} if $dbline{$i} eq '';
		    next CMD; };
		$cmd =~ /^A$/ && 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; };
		$cmd =~ /^<\s*(.*)/ && do {
		    $pre = do action($1);
		    next CMD; };
		$cmd =~ /^>\s*(.*)/ && do {
		    $post = do action($1);
		    next CMD; };
		$cmd =~ /^a\b\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; };
		$cmd =~ /^n$/ && do {
		    $single = 2;
		    $laststep = $cmd;
		    last CMD; };
		$cmd =~ /^s$/ && do {
		    $single = 1;
		    $laststep = $cmd;
		    last CMD; };
		$cmd =~ /^c\b\s*(\d*)\s*$/ && do {
		    $i = $1;
		    if ($i) {
			if ($dbline[$i] == 0) {
			    print OUT "Line $i not breakable.\n";
			    next CMD;
			}
			$dbline{$i} =~ s/(\0|$)/;9$1/;	# add one-time-only b.p.
		    }
		    for ($i=0; $i <= $#stack; ) {
			$stack[$i++] &= ~1;
		    }
		    last CMD; };
		$cmd =~ /^r$/ && do {
		    $stack[$#stack] |= 2;
		    last CMD; };
		$cmd =~ /^T$/ && 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; };
		$cmd =~ /^\/(.*)$/ && do {
		    $inpat = $1;
		    $inpat =~ s:([^\\])/$:$1:;
		    if ($inpat ne "") {
			eval '$inpat =~ m'."\n$inpat\n";	
			if ($@ ne "") {
			    print OUT "$@";
			    next CMD;
			}
			$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; };
		$cmd =~ /^\?(.*)$/ && do {
		    $inpat = $1;
		    $inpat =~ s:([^\\])\?$:$1:;
		    if ($inpat ne "") {
			eval '$inpat =~ m'."\n$inpat\n";	
			if ($@ ne "") {
			    print OUT "$@";
			    next CMD;
			}
			$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; };
		$cmd =~ /^!+\s*(-)?(\d+)?$/ && 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; };
		$cmd =~ /^!(.+)$/ && 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;
		    }
		    $cmd = $hist[$i] . "\n";
		    print OUT $cmd;
		    redo CMD; };
		$cmd =~ /^H\b\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; };
		$cmd =~ s/^p( .*)?$/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 CMD; };
	    }
	    $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
9ef589d8	3	$header = '$RCSfile: perldb.pl,v $$Revision: 4.0.1.1 $$Date: 91/06/07 11:17:44 $';
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 $
9ef589d8	13	# Revision 4.0.1.1 91/06/07 11:17:44 lwall
	14	# patch4: added $^P variable to control calling of perldb routines
	15	# patch4: debugger sometimes listed wrong number of lines for a statement
	16	#
fe14fcc3	17	# Revision 4.0 91/03/20 01:25:50 lwall
	18	# 4.0 baseline.
	19	#
27e2fb84	20	# Revision 3.0.1.6 91/01/11 18:08:58 lwall
	21	# patch42: @_ couldn't be accessed from debugger
	22	#
34de22dd	23	# Revision 3.0.1.5 90/11/10 01:40:26 lwall
	24	# patch38: the debugger wouldn't stop correctly or do action routines
	25	#
76854fea	26	# Revision 3.0.1.4 90/10/15 17:40:38 lwall
	27	# patch29: added caller
	28	# patch29: the debugger now understands packages and evals
	29	# patch29: scripts now run at almost full speed under the debugger
	30	# patch29: more variables are settable from debugger
	31	#
33b78306	32	# Revision 3.0.1.3 90/08/09 04:00:58 lwall
	33	# patch19: debugger now allows continuation lines
	34	# patch19: debugger can now dump lists of variables
	35	# patch19: debugger can now add aliases easily from prompt
	36	#
79a0689e	37	# Revision 3.0.1.2 90/03/12 16:39:39 lwall
	38	# patch13: perl -d didn't format stack traces of *foo right
	39	# patch13: perl -d wiped out scalar return values of subroutines
	40	#
03a14243	41	# Revision 3.0.1.1 89/10/26 23:14:02 lwall
	42	# patch1: RCS expanded an unintended $Header in lib/perldb.pl
	43	#
a687059c	44	# Revision 3.0 89/10/18 15:19:46 lwall
	45	# 3.0 baseline
	46	#
	47	# Revision 2.0 88/06/05 00:09:45 root
	48	# Baseline version 2.0.
	49	#
	50	#
	51
76854fea	52	open(IN, "</dev/tty") \|\| open(IN, "<&STDIN"); # so we don't dingle stdin
76854fea	53	open(OUT,">/dev/tty") \|\| open(OUT, ">&STDOUT"); # so we don't dongle stdout
a687059c	54	select(OUT);
	55	$\| = 1; # for DB'OUT
	56	select(STDOUT);
	57	$\| = 1; # for real STDOUT
76854fea	58	$sub = '';
a687059c	59
03a14243	60	$header =~ s/.Header: ([^,]+),v(\s+\S+\s+\S+).*$/$1$2/;
76854fea	61	print OUT "\nLoading DB routines from $header\n\nEnter h for help.\n\n";
a687059c	62
a687059c	63	sub DB {
76854fea	64	&save;
	65	($package, $filename, $line) = caller;
	66	$usercontext = '($@, $!, $[, $,, $/, $\) = @saved;' .
	67	"package $package;"; # this won't let them modify, alas
9ef589d8	68	local($^P) = 0; # don't debug our own evals
76854fea	69	local(*dbline) = "_<$filename";
	70	$max = $#dbline;
	71	if (($stop,$action) = split(/\0/,$dbline{$line})) {
a687059c	72	if ($stop eq '1') {
	73	$signal \|= 1;
	74	}
	75	else {
27e2fb84	76	$evalarg = "\$DB'signal \|= do {$stop;}"; &eval;
76854fea	77	$dbline{$line} =~ s/;9($\|\0)/$1/;
a687059c	78	}
	79	}
	80	if ($single \|\| $trace \|\| $signal) {
76854fea	81	print OUT "$package'" unless $sub =~ /'/;
	82	print OUT "$sub($filename:$line):\t",$dbline[$line];
	83	for ($i = $line + 1; $i <= $max && $dbline[$i] == 0; ++$i) {
9ef589d8	84	last if $dbline[$i] =~ /^\s*(;\|}\|#\|\n)/;
76854fea	85	print OUT "$sub($filename:$i):\t",$dbline[$i];
a687059c	86	}
a687059c	87	}
27e2fb84	88	$evalarg = $action, &eval if $action;
a687059c	89	if ($single \|\| $signal) {
27e2fb84	90	$evalarg = $pre, &eval if $pre;
a687059c	91	print OUT $#stack . " levels deep in subroutine calls!\n"
	92	if $single & 4;
	93	$start = $line;
fe14fcc3	94	CMD:
76854fea	95	while ((print OUT " DB<", $#hist+1, "> "), $cmd=&gets) {
fe14fcc3	96	{
	97	$single = 0;
	98	$signal = 0;
	99	$cmd eq '' && exit 0;
	100	chop($cmd);
	101	$cmd =~ s/\\$// && do {
	102	print OUT " cont: ";
	103	$cmd .= &gets;
	104	redo CMD;
	105	};
	106	$cmd =~ /^q$/ && exit 0;
	107	$cmd =~ /^$/ && ($cmd = $laststep);
	108	push(@hist,$cmd) if length($cmd) > 1;
	109	($i) = split(/\s+/,$cmd);
	110	eval "\$cmd =~ $alias{$i}", print OUT $@ if $alias{$i};
	111	$cmd =~ /^h$/ && do {
	112	print OUT "
a687059c	113	T Stack trace.
	114	s Single step.
	115	n Next, steps over subroutine calls.
76854fea	116	r Return from current subroutine.
a687059c	117	c [line] Continue; optionally inserts a one-time-only breakpoint
	118	at the specified line.
	119	<CR> Repeat last n or s.
	120	l min+incr List incr+1 lines starting at min.
	121	l min-max List lines.
	122	l line List line;
	123	l List next window.
	124	- List previous window.
	125	w line List window around line.
	126	l subname List subroutine.
76854fea	127	f filename Switch to filename.
a687059c	128	/pattern/ Search forwards for pattern; final / is optional.
	129	?pattern? Search backwards for pattern.
	130	L List breakpoints and actions.
	131	S List subroutine names.
	132	t Toggle trace mode.
	133	b [line] [condition]
	134	Set breakpoint; line defaults to the current execution line;
	135	condition breaks if it evaluates to true, defaults to \'1\'.
	136	b subname [condition]
	137	Set breakpoint at first line of subroutine.
	138	d [line] Delete breakpoint.
	139	D Delete all breakpoints.
	140	a [line] command
	141	Set an action to be done before the line is executed.
	142	Sequence is: check for breakpoint, print line if necessary,
	143	do action, prompt user if breakpoint or step, evaluate line.
	144	A Delete all actions.
76854fea	145	V [pkg [vars]] List some (default all) variables in package (default current).
76854fea	146	X [vars] Same as \"V currentpackage [vars]\".
a687059c	147	< command Define command before prompt.
	148	> command Define command after prompt.
	149	! number Redo command (default previous command).
	150	! -number Redo number\'th to last command.
	151	H -number Display last number commands (default all).
	152	q or ^D Quit.
76854fea	153	p expr Same as \"print DB'OUT expr\" in current package.
33b78306	154	= [alias value] Define a command alias, or list current aliases.
76854fea	155	command Execute as a perl statement in current package.
a687059c	156
a687059c	157	";
fe14fcc3	158	next CMD; };
	159	$cmd =~ /^t$/ && do {
	160	$trace = !$trace;
	161	print OUT "Trace = ".($trace?"on":"off")."\n";
	162	next CMD; };
	163	$cmd =~ /^S$/ && do {
	164	foreach $subname (sort(keys %sub)) {
	165	print OUT $subname,"\n";
	166	}
	167	next CMD; };
	168	$cmd =~ s/^X\b/V $package/;
	169	$cmd =~ /^V$/ && do {
	170	$cmd = 'V $package'; };
	171	$cmd =~ /^V\b\s(\S+)\s(.*)/ && do {
	172	$packname = $1;
	173	@vars = split(' ',$2);
	174	do 'dumpvar.pl' unless defined &main'dumpvar;
	175	if (defined &main'dumpvar) {
	176	&main'dumpvar($packname,@vars);
	177	}
	178	else {
	179	print DB'OUT "dumpvar.pl not available.\n";
76854fea	180	}
fe14fcc3	181	next CMD; };
	182	$cmd =~ /^f\b\s(.)/ && do {
	183	$file = $1;
	184	if (!$file) {
	185	print OUT "The old f command is now the r command.\n";
	186	print OUT "The new f command switches filenames.\n";
	187	next CMD;
a687059c	188	}
fe14fcc3	189	if (!defined $_main{'_<' . $file}) {
	190	if (($try) = grep(m#^_<.*$file#, keys %_main)) {
	191	$file = substr($try,2);
	192	print "\n$file:\n";
76854fea	193	}
76854fea	194	}
fe14fcc3	195	if (!defined $_main{'_<' . $file}) {
	196	print OUT "There's no code here anything matching $file.\n";
	197	next CMD;
	198	}
	199	elsif ($file ne $filename) {
	200	*dbline = "_<$file";
	201	$max = $#dbline;
	202	$filename = $file;
	203	$start = 1;
	204	$cmd = "l";
	205	} };
	206	$cmd =~ /^l\b\s(['A-Za-z_]['\w])/ && do {
	207	$subname = $1;
	208	$subname = "main'" . $subname unless $subname =~ /'/;
	209	$subname = "main" . $subname if substr($subname,0,1) eq "'";
	210	($file,$subrange) = split(/:/,$sub{$subname});
	211	if ($file ne $filename) {
	212	*dbline = "_<$file";
	213	$max = $#dbline;
	214	$filename = $file;
	215	}
	216	if ($subrange) {
	217	if (eval($subrange) < -$window) {
	218	$subrange =~ s/-.*/+/;
	219	}
	220	$cmd = "l $subrange";
	221	} else {
	222	print OUT "Subroutine $1 not found.\n";
	223	next CMD;
	224	} };
	225	$cmd =~ /^w\b\s(\d)$/ && do {
	226	$incr = $window - 1;
	227	$start = $1 if $1;
	228	$start -= $preview;
	229	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	230	$cmd =~ /^-$/ && do {
	231	$incr = $window - 1;
	232	$cmd = 'l ' . ($start-$window*2) . '+'; };
	233	$cmd =~ /^l$/ && do {
	234	$incr = $window - 1;
	235	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	236	$cmd =~ /^l\b\s(\d)\+(\d*)$/ && do {
	237	$start = $1 if $1;
	238	$incr = $2;
	239	$incr = $window - 1 unless $incr;
	240	$cmd = 'l ' . $start . '-' . ($start + $incr); };
	241	$cmd =~ /^l\b\s*(([\d\$\.]+)([-,]([\d\$\.]+))?)?/ && do {
	242	$end = (!$2) ? $max : ($4 ? $4 : $2);
	243	$end = $max if $end > $max;
	244	$i = $2;
	245	$i = $line if $i eq '.';
	246	$i = 1 if $i < 1;
	247	for (; $i <= $end; $i++) {
76854fea	248	print OUT "$i:\t", $dbline[$i];
a687059c	249	last if $signal;
a687059c	250	}
fe14fcc3	251	$start = $i; # remember in case they want more
	252	$start = $max if $start > $max;
	253	next CMD; };
	254	$cmd =~ /^D$/ && do {
	255	print OUT "Deleting all breakpoints...\n";
	256	for ($i = 1; $i <= $max ; $i++) {
	257	if (defined $dbline{$i}) {
	258	$dbline{$i} =~ s/^[^\0]+//;
	259	if ($dbline{$i} =~ s/^\0?$//) {
	260	delete $dbline{$i};
	261	}
	262	}
	263	}
	264	next CMD; };
	265	$cmd =~ /^L$/ && do {
	266	for ($i = 1; $i <= $max; $i++) {
	267	if (defined $dbline{$i}) {
	268	print OUT "$i:\t", $dbline[$i];
	269	($stop,$action) = split(/\0/, $dbline{$i});
	270	print OUT " break if (", $stop, ")\n"
	271	if $stop;
	272	print OUT " action: ", $action, "\n"
	273	if $action;
	274	last if $signal;
	275	}
	276	}
	277	next CMD; };
	278	$cmd =~ /^b\b\s(['A-Za-z_]['\w])\s(.)/ && do {
	279	$subname = $1;
	280	$cond = $2 \|\| '1';
	281	$subname = "$package'" . $subname unless $subname =~ /'/;
	282	$subname = "main" . $subname if substr($subname,0,1) eq "'";
	283	($filename,$i) = split(/[:-]/, $sub{$subname});
	284	if ($i) {
	285	*dbline = "_<$filename";
	286	++$i while $dbline[$i] == 0 && $i < $#dbline;
	287	$dbline{$i} =~ s/^[^\0]*/$cond/;
	288	} else {
	289	print OUT "Subroutine $subname not found.\n";
76854fea	290	}
fe14fcc3	291	next CMD; };
	292	$cmd =~ /^b\b\s(\d)\s(.)/ && do {
	293	$i = ($1?$1:$line);
	294	$cond = $2 \|\| '1';
76854fea	295	if ($dbline[$i] == 0) {
fe14fcc3	296	print OUT "Line $i not breakable.\n";
	297	} else {
	298	$dbline{$i} =~ s/^[^\0]*/$cond/;
a687059c	299	}
fe14fcc3	300	next CMD; };
	301	$cmd =~ /^d\b\s*(\d+)?/ && do {
	302	$i = ($1?$1:$line);
	303	$dbline{$i} =~ s/^[^\0]*//;
	304	delete $dbline{$i} if $dbline{$i} eq '';
	305	next CMD; };
	306	$cmd =~ /^A$/ && do {
	307	for ($i = 1; $i <= $max ; $i++) {
	308	if (defined $dbline{$i}) {
	309	$dbline{$i} =~ s/\0[^\0]*//;
	310	delete $dbline{$i} if $dbline{$i} eq '';
76854fea	311	}
fe14fcc3	312	}
	313	next CMD; };
	314	$cmd =~ /^<\s(.)/ && do {
	315	$pre = do action($1);
	316	next CMD; };
	317	$cmd =~ /^>\s(.)/ && do {
	318	$post = do action($1);
	319	next CMD; };
	320	$cmd =~ /^a\b\s(\d+)(\s+(.))?/ && do {
	321	$i = $1;
	322	if ($dbline[$i] == 0) {
	323	print OUT "Line $i may not have an action.\n";
	324	} else {
	325	$dbline{$i} =~ s/\0[^\0]*//;
	326	$dbline{$i} .= "\0" . do action($3);
	327	}
	328	next CMD; };
	329	$cmd =~ /^n$/ && do {
	330	$single = 2;
	331	$laststep = $cmd;
	332	last CMD; };
	333	$cmd =~ /^s$/ && do {
	334	$single = 1;
	335	$laststep = $cmd;
	336	last CMD; };
	337	$cmd =~ /^c\b\s(\d)\s*$/ && do {
	338	$i = $1;
	339	if ($i) {
	340	if ($dbline[$i] == 0) {
	341	print OUT "Line $i not breakable.\n";
	342	next CMD;
76854fea	343	}
fe14fcc3	344	$dbline{$i} =~ s/(\0\|$)/;9$1/; # add one-time-only b.p.
76854fea	345	}
fe14fcc3	346	for ($i=0; $i <= $#stack; ) {
fe14fcc3	347	$stack[$i++] &= ~1;
a687059c	348	}
fe14fcc3	349	last CMD; };
	350	$cmd =~ /^r$/ && do {
	351	$stack[$#stack] \|= 2;
	352	last CMD; };
	353	$cmd =~ /^T$/ && do {
	354	local($p,$f,$l,$s,$h,$a,@a,@sub);
	355	for ($i = 1; ($p,$f,$l,$s,$h,$w) = caller($i); $i++) {
	356	@a = @args;
	357	for (@a) {
	358	if (/^StB\000/ && length($_) == length($_main{'_main'})) {
	359	$_ = sprintf("%s",$_);
	360	}
	361	else {
	362	s/'/\\'/g;
	363	s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/;
	364	s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
	365	s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
	366	}
	367	}
	368	$w = $w ? '@ = ' : '$ = ';
	369	$a = $h ? '(' . join(', ', @a) . ')' : '';
	370	push(@sub, "$w&$s$a from file $f line $l\n");
	371	last if $signal;
a687059c	372	}
fe14fcc3	373	for ($i=0; $i <= $#sub; $i++) {
	374	last if $signal;
	375	print OUT $sub[$i];
a687059c	376	}
fe14fcc3	377	next CMD; };
	378	$cmd =~ /^\/(.*)$/ && do {
	379	$inpat = $1;
	380	$inpat =~ s:([^\\])/$:$1:;
	381	if ($inpat ne "") {
	382	eval '$inpat =~ m'."\n$inpat\n";
	383	if ($@ ne "") {
	384	print OUT "$@";
	385	next CMD;
	386	}
	387	$pat = $inpat;
a687059c	388	}
fe14fcc3	389	$end = $start;
	390	eval '
	391	for (;;) {
	392	++$start;
	393	$start = 1 if ($start > $max);
	394	last if ($start == $end);
	395	if ($dbline[$start] =~ m'."\n$pat\n".'i) {
	396	print OUT "$start:\t", $dbline[$start], "\n";
	397	last;
	398	}
	399	} ';
	400	print OUT "/$pat/: not found\n" if ($start == $end);
	401	next CMD; };
	402	$cmd =~ /^\?(.*)$/ && do {
	403	$inpat = $1;
	404	$inpat =~ s:([^\\])\?$:$1:;
	405	if ($inpat ne "") {
	406	eval '$inpat =~ m'."\n$inpat\n";
	407	if ($@ ne "") {
	408	print OUT "$@";
	409	next CMD;
	410	}
	411	$pat = $inpat;
	412	}
	413	$end = $start;
	414	eval '
	415	for (;;) {
	416	--$start;
	417	$start = $max if ($start <= 0);
	418	last if ($start == $end);
	419	if ($dbline[$start] =~ m'."\n$pat\n".'i) {
	420	print OUT "$start:\t", $dbline[$start], "\n";
	421	last;
	422	}
	423	} ';
	424	print OUT "?$pat?: not found\n" if ($start == $end);
	425	next CMD; };
	426	$cmd =~ /^!+\s*(-)?(\d+)?$/ && do {
	427	pop(@hist) if length($cmd) > 1;
	428	$i = ($1?($#hist-($2?$2:1)):($2?$2:$#hist));
	429	$cmd = $hist[$i] . "\n";
	430	print OUT $cmd;
	431	redo CMD; };
	432	$cmd =~ /^!(.+)$/ && do {
	433	$pat = "^$1";
	434	pop(@hist) if length($cmd) > 1;
	435	for ($i = $#hist; $i; --$i) {
	436	last if $hist[$i] =~ $pat;
	437	}
	438	if (!$i) {
	439	print OUT "No such command!\n\n";
	440	next CMD;
	441	}
	442	$cmd = $hist[$i] . "\n";
	443	print OUT $cmd;
	444	redo CMD; };
	445	$cmd =~ /^H\b\s*(-(\d+))?/ && do {
	446	$end = $2?($#hist-$2):0;
	447	$hist = 0 if $hist < 0;
	448	for ($i=$#hist; $i>$end; $i--) {
	449	print OUT "$i: ",$hist[$i],"\n"
	450	unless $hist[$i] =~ /^.?$/;
	451	};
	452	next CMD; };
453	$cmd =~ s/^p( .*)?$/print DB'OUT$1/;
454	$cmd =~ /^=/ && do {
455	if (local($k,$v) = ($cmd =~ /^=\s(\S+)\s+(.)/)) {
456	$alias{$k}="s~$k~$v~";
457	print OUT "$k = $v\n";
458	} elsif ($cmd =~ /^=\s*$/) {
459	foreach $k (sort keys(%alias)) {
460	if (($v = $alias{$k}) =~ s~^s\~$k\~(.*)\~$~$1~) {
461	print OUT "$k = $v\n";
462	} else {
463	print OUT "$k\t$alias{$k}\n";
464	};
33b78306	465	};
33b78306	466	};
fe14fcc3	467	next CMD; };
fe14fcc3	468	}
27e2fb84	469	$evalarg = $cmd; &eval;
76854fea	470	print OUT "\n";
a687059c	471	}
a687059c	472	if ($post) {
27e2fb84	473	$evalarg = $post; &eval;
a687059c	474	}
a687059c	475	}
76854fea	476	($@, $!, $[, $,, $/, $\) = @saved;
	477	}
	478
	479	sub save {
	480	@saved = ($@, $!, $[, $,, $/, $\);
	481	$[ = 0; $, = ""; $/ = "\n"; $\ = "";
	482	}
	483
27e2fb84	484	# The following takes its argument via $evalarg to preserve current @_
27e2fb84	485
76854fea	486	sub eval {
27e2fb84	487	eval "$usercontext $evalarg; &DB'save";
76854fea	488	print OUT $@;
a687059c	489	}
	490
	491	sub action {
	492	local($action) = @_;
	493	while ($action =~ s/\\$//) {
	494	print OUT "+ ";
76854fea	495	$action .= &gets;
a687059c	496	}
	497	$action;
	498	}
	499
76854fea	500	sub gets {
	501	local($.);
	502	<IN>;
	503	}
	504
a687059c	505	sub catch {
	506	$signal = 1;
	507	}
	508
	509	sub sub {
	510	push(@stack, $single);
	511	$single &= 1;
	512	$single \|= 4 if $#stack == $deep;
a687059c	513	if (wantarray) {
a687059c	514	@i = &$sub;
79a0689e	515	$single \|= pop(@stack);
79a0689e	516	@i;
a687059c	517	}
	518	else {
	519	$i = &$sub;
79a0689e	520	$single \|= pop(@stack);
79a0689e	521	$i;
a687059c	522	}
a687059c	523	}
	524
	525	$single = 1; # so it stops on first executable statement
a687059c	526	@hist = ('?');
	527	$SIG{'INT'} = "DB'catch";
	528	$deep = 100; # warning if stack gets this deep
	529	$window = 10;
	530	$preview = 3;
	531
	532	@stack = (0);
76854fea	533	@ARGS = @ARGV;
a687059c	534	for (@args) {
	535	s/'/\\'/g;
	536	s/(.*)/'$1'/ unless /^-?[\d.]+$/;
	537	}
a687059c	538
	539	if (-f '.perldb') {
	540	do './.perldb';
	541	}
	542	elsif (-f "$ENV{'LOGDIR'}/.perldb") {
	543	do "$ENV{'LOGDIR'}/.perldb";
	544	}
	545	elsif (-f "$ENV{'HOME'}/.perldb") {
	546	do "$ENV{'HOME'}/.perldb";
	547	}
	548
	549	1;