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43d8869b |
1 | # |
2 | # Documentation is at the __END__ |
3 | # |
4 | |
5 | package DB; |
6 | |
7 | # "private" globals |
8 | |
9 | my ($running, $ready, $deep, $usrctxt, $evalarg, |
10 | @stack, @saved, @skippkg, @clients); |
11 | my $preeval = {}; |
12 | my $posteval = {}; |
13 | my $ineval = {}; |
14 | |
15 | #### |
16 | # |
17 | # Globals - must be defined at startup so that clients can refer to |
18 | # them right after a C<require DB;> |
19 | # |
20 | #### |
21 | |
22 | BEGIN { |
23 | |
24 | # these are hardcoded in perl source (some are magical) |
25 | |
26 | $DB::sub = ''; # name of current subroutine |
27 | %DB::sub = (); # "filename:fromline-toline" for every known sub |
28 | $DB::single = 0; # single-step flag (set it to 1 to enable stops in BEGIN/use) |
29 | $DB::signal = 0; # signal flag (will cause a stop at the next line) |
30 | $DB::trace = 0; # are we tracing through subroutine calls? |
31 | @DB::args = (); # arguments of current subroutine or @ARGV array |
32 | @DB::dbline = (); # list of lines in currently loaded file |
33 | %DB::dbline = (); # actions in current file (keyed by line number) |
34 | @DB::ret = (); # return value of last sub executed in list context |
35 | $DB::ret = ''; # return value of last sub executed in scalar context |
36 | |
37 | # other "public" globals |
38 | |
39 | $DB::package = ''; # current package space |
40 | $DB::filename = ''; # current filename |
41 | $DB::subname = ''; # currently executing sub (fullly qualified name) |
42 | $DB::lineno = ''; # current line number |
43 | |
44 | $DB::VERSION = $DB::VERSION = '1.0'; |
45 | |
46 | # initialize private globals to avoid warnings |
47 | |
48 | $running = 1; # are we running, or are we stopped? |
49 | @stack = (0); |
50 | @clients = (); |
51 | $deep = 100; |
52 | $ready = 0; |
53 | @saved = (); |
54 | @skippkg = (); |
55 | $usrctxt = ''; |
56 | $evalarg = ''; |
57 | } |
58 | |
59 | #### |
60 | # entry point for all subroutine calls |
61 | # |
62 | sub sub { |
63 | push(@stack, $DB::single); |
64 | $DB::single &= 1; |
65 | $DB::single |= 4 if $#stack == $deep; |
66 | # print $DB::sub, "\n"; |
67 | if ($DB::sub =~ /(?:^|::)DESTROY$/ or not defined wantarray) { |
68 | &$DB::sub; |
69 | $DB::single |= pop(@stack); |
70 | $DB::ret = undef; |
71 | } |
72 | elsif (wantarray) { |
73 | @DB::ret = &$DB::sub; |
74 | $DB::single |= pop(@stack); |
75 | @DB::ret; |
76 | } |
77 | else { |
78 | $DB::ret = &$DB::sub; |
79 | $DB::single |= pop(@stack); |
80 | $DB::ret; |
81 | } |
82 | } |
83 | |
84 | #### |
85 | # this is called by perl for every statement |
86 | # |
87 | sub DB { |
88 | return unless $ready; |
89 | &save; |
90 | ($DB::package, $DB::filename, $DB::lineno) = caller; |
91 | |
92 | return if @skippkg and grep { $_ eq $DB::package } @skippkg; |
93 | |
94 | $usrctxt = "package $DB::package;"; # this won't let them modify, alas |
95 | local(*DB::dbline) = "::_<$DB::filename"; |
96 | my ($stop, $action); |
97 | if (($stop,$action) = split(/\0/,$DB::dbline{$DB::lineno})) { |
98 | if ($stop eq '1') { |
99 | $DB::signal |= 1; |
100 | } |
101 | else { |
102 | $stop = 0 unless $stop; # avoid un_init warning |
103 | $evalarg = "\$DB::signal |= do { $stop; }"; &eval; |
104 | $DB::dbline{$DB::lineno} =~ s/;9($|\0)/$1/; # clear any temp breakpt |
105 | } |
106 | } |
107 | if ($DB::single || $DB::trace || $DB::signal) { |
108 | $DB::subname = ($DB::sub =~ /\'|::/) ? $DB::sub : "${DB::package}::$DB::sub"; #'; |
109 | DB->loadfile($DB::filename, $DB::lineno); |
110 | } |
111 | $evalarg = $action, &eval if $action; |
112 | if ($DB::single || $DB::signal) { |
113 | _outputall($#stack . " levels deep in subroutine calls.\n") if $DB::single & 4; |
114 | $DB::single = 0; |
115 | $DB::signal = 0; |
116 | $running = 0; |
117 | |
118 | &eval if ($evalarg = DB->prestop); |
119 | my $c; |
120 | for $c (@clients) { |
121 | # perform any client-specific prestop actions |
122 | &eval if ($evalarg = $c->cprestop); |
123 | |
124 | # Now sit in an event loop until something sets $running |
125 | do { |
126 | $c->idle; # call client event loop; must not block |
127 | if ($running == 2) { # client wants something eval-ed |
128 | &eval if ($evalarg = $c->evalcode); |
129 | $running = 0; |
130 | } |
131 | } until $running; |
132 | |
133 | # perform any client-specific poststop actions |
134 | &eval if ($evalarg = $c->cpoststop); |
135 | } |
136 | &eval if ($evalarg = DB->poststop); |
137 | } |
138 | ($@, $!, $,, $/, $\, $^W) = @saved; |
139 | (); |
140 | } |
141 | |
142 | #### |
143 | # this takes its argument via $evalarg to preserve current @_ |
144 | # |
145 | sub eval { |
146 | ($@, $!, $,, $/, $\, $^W) = @saved; |
147 | eval "$usrctxt $evalarg; &DB::save"; |
148 | _outputall($@) if $@; |
149 | } |
150 | |
151 | ############################################################################### |
152 | # no compile-time subroutine call allowed before this point # |
153 | ############################################################################### |
154 | |
155 | use strict; # this can run only after DB() and sub() are defined |
156 | |
157 | sub save { |
158 | @saved = ($@, $!, $,, $/, $\, $^W); |
159 | $, = ""; $/ = "\n"; $\ = ""; $^W = 0; |
160 | } |
161 | |
162 | sub catch { |
163 | for (@clients) { $_->awaken; } |
164 | $DB::signal = 1; |
165 | $ready = 1; |
166 | } |
167 | |
168 | #### |
169 | # |
170 | # Client callable (read inheritable) methods defined after this point |
171 | # |
172 | #### |
173 | |
174 | sub register { |
175 | my $s = shift; |
176 | $s = _clientname($s) if ref($s); |
177 | push @clients, $s; |
178 | } |
179 | |
180 | sub done { |
181 | my $s = shift; |
182 | $s = _clientname($s) if ref($s); |
183 | @clients = grep {$_ ne $s} @clients; |
184 | $s->cleanup; |
185 | # $running = 3 unless @clients; |
186 | exit(0) unless @clients; |
187 | } |
188 | |
189 | sub _clientname { |
190 | my $name = shift; |
191 | "$name" =~ /^(.+)=[A-Z]+\(.+\)$/; |
192 | return $1; |
193 | } |
194 | |
195 | sub next { |
196 | my $s = shift; |
197 | $DB::single = 2; |
198 | $running = 1; |
199 | } |
200 | |
201 | sub step { |
202 | my $s = shift; |
203 | $DB::single = 1; |
204 | $running = 1; |
205 | } |
206 | |
207 | sub cont { |
208 | my $s = shift; |
209 | my $i = shift; |
210 | $s->set_tbreak($i) if $i; |
211 | for ($i = 0; $i <= $#stack;) { |
212 | $stack[$i++] &= ~1; |
213 | } |
214 | $DB::single = 0; |
215 | $running = 1; |
216 | } |
217 | |
218 | #### |
219 | # XXX caller must experimentally determine $i (since it depends |
220 | # on how many client call frames are between this call and the DB call). |
221 | # Such is life. |
222 | # |
223 | sub ret { |
224 | my $s = shift; |
225 | my $i = shift; # how many levels to get to DB sub |
226 | $i = 0 unless defined $i; |
227 | $stack[$#stack-$i] |= 1; |
228 | $DB::single = 0; |
229 | $running = 1; |
230 | } |
231 | |
232 | #### |
233 | # XXX caller must experimentally determine $start (since it depends |
234 | # on how many client call frames are between this call and the DB call). |
235 | # Such is life. |
236 | # |
237 | sub backtrace { |
238 | my $self = shift; |
239 | my $start = shift; |
240 | my($p,$f,$l,$s,$h,$w,$e,$r,$a, @a, @ret,$i); |
241 | $start = 1 unless $start; |
242 | for ($i = $start; ($p,$f,$l,$s,$h,$w,$e,$r) = caller($i); $i++) { |
243 | @a = @DB::args; |
244 | for (@a) { |
245 | s/'/\\'/g; |
246 | s/([^\0]*)/'$1'/ unless /^-?[\d.]+$/; |
247 | s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg; |
248 | s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg; |
249 | } |
250 | $w = $w ? '@ = ' : '$ = '; |
251 | $a = $h ? '(' . join(', ', @a) . ')' : ''; |
252 | $e =~ s/\n\s*\;\s*\Z// if $e; |
253 | $e =~ s/[\\\']/\\$1/g if $e; |
254 | if ($r) { |
255 | $s = "require '$e'"; |
256 | } elsif (defined $r) { |
257 | $s = "eval '$e'"; |
258 | } elsif ($s eq '(eval)') { |
259 | $s = "eval {...}"; |
260 | } |
261 | $f = "file `$f'" unless $f eq '-e'; |
262 | push @ret, "$w&$s$a from $f line $l"; |
263 | last if $DB::signal; |
264 | } |
265 | return @ret; |
266 | } |
267 | |
268 | sub _outputall { |
269 | my $c; |
270 | for $c (@clients) { |
271 | $c->output(@_); |
272 | } |
273 | } |
274 | |
275 | sub trace_toggle { |
276 | my $s = shift; |
277 | $DB::trace = !$DB::trace; |
278 | } |
279 | |
280 | |
281 | #### |
282 | # without args: returns all defined subroutine names |
283 | # with subname args: returns a listref [file, start, end] |
284 | # |
285 | sub subs { |
286 | my $s = shift; |
287 | if (@_) { |
288 | my(@ret) = (); |
289 | while (@_) { |
290 | my $name = shift; |
291 | push @ret, [$DB::sub{$name} =~ /^(.*)\:(\d+)-(\d+)$/] |
292 | if exists $DB::sub{$name}; |
293 | } |
294 | return @ret; |
295 | } |
296 | return keys %DB::sub; |
297 | } |
298 | |
299 | #### |
300 | # first argument is a filename whose subs will be returned |
301 | # if a filename is not supplied, all subs in the current |
302 | # filename are returned. |
303 | # |
304 | sub filesubs { |
305 | my $s = shift; |
306 | my $fname = shift; |
307 | $fname = $DB::filename unless $fname; |
308 | return grep { $DB::sub{$_} =~ /^$fname/ } keys %DB::sub; |
309 | } |
310 | |
311 | #### |
312 | # returns a list of all filenames that DB knows about |
313 | # |
314 | sub files { |
315 | my $s = shift; |
316 | my(@f) = grep(m|^_<|, keys %main::); |
317 | return map { substr($_,2) } @f; |
318 | } |
319 | |
320 | #### |
321 | # returns reference to an array holding the lines in currently |
322 | # loaded file |
323 | # |
324 | sub lines { |
325 | my $s = shift; |
326 | return \@DB::dbline; |
327 | } |
328 | |
329 | #### |
330 | # loadfile($file, $line) |
331 | # |
332 | sub loadfile { |
333 | my $s = shift; |
334 | my($file, $line) = @_; |
335 | if (!defined $main::{'_<' . $file}) { |
336 | my $try; |
337 | if (($try) = grep(m|^_<.*$file|, keys %main::)) { |
338 | $file = substr($try,2); |
339 | } |
340 | } |
341 | if (defined($main::{'_<' . $file})) { |
342 | my $c; |
343 | # _outputall("Loading file $file.."); |
344 | *DB::dbline = "::_<$file"; |
345 | $DB::filename = $file; |
346 | for $c (@clients) { |
347 | # print "2 ", $file, '|', $line, "\n"; |
348 | $c->showfile($file, $line); |
349 | } |
350 | return $file; |
351 | } |
352 | return undef; |
353 | } |
354 | |
355 | sub lineevents { |
356 | my $s = shift; |
357 | my $fname = shift; |
358 | my(%ret) = (); |
359 | my $i; |
360 | $fname = $DB::filename unless $fname; |
361 | local(*DB::dbline) = "::_<$fname"; |
362 | for ($i = 1; $i <= $#DB::dbline; $i++) { |
363 | $ret{$i} = [$DB::dbline[$i], split(/\0/, $DB::dbline{$i})] |
364 | if defined $DB::dbline{$i}; |
365 | } |
366 | return %ret; |
367 | } |
368 | |
369 | sub set_break { |
370 | my $s = shift; |
371 | my $i = shift; |
372 | my $cond = shift; |
373 | $i ||= $DB::lineno; |
374 | $cond ||= '1'; |
375 | $i = _find_subline($i) if ($i =~ /\D/); |
376 | $s->output("Subroutine not found.\n") unless $i; |
377 | if ($i) { |
378 | if ($DB::dbline[$i] == 0) { |
379 | $s->output("Line $i not breakable.\n"); |
380 | } |
381 | else { |
382 | $DB::dbline{$i} =~ s/^[^\0]*/$cond/; |
383 | } |
384 | } |
385 | } |
386 | |
387 | sub set_tbreak { |
388 | my $s = shift; |
389 | my $i = shift; |
390 | $i = _find_subline($i) if ($i =~ /\D/); |
391 | $s->output("Subroutine not found.\n") unless $i; |
392 | if ($i) { |
393 | if ($DB::dbline[$i] == 0) { |
394 | $s->output("Line $i not breakable.\n"); |
395 | } |
396 | else { |
397 | $DB::dbline{$i} =~ s/($|\0)/;9$1/; # add one-time-only b.p. |
398 | } |
399 | } |
400 | } |
401 | |
402 | sub _find_subline { |
403 | my $name = shift; |
404 | $name =~ s/\'/::/; |
405 | $name = "${DB::package}\:\:" . $name if $name !~ /::/; |
406 | $name = "main" . $name if substr($name,0,2) eq "::"; |
407 | my($fname, $from, $to) = ($DB::sub{$name} =~ /^(.*):(\d+)-(\d+)$/); |
408 | if ($from) { |
c95f170b |
409 | local *DB::dbline = "::_<$fname"; |
43d8869b |
410 | ++$from while $DB::dbline[$from] == 0 && $from < $to; |
411 | return $from; |
412 | } |
413 | return undef; |
414 | } |
415 | |
416 | sub clr_breaks { |
417 | my $s = shift; |
418 | my $i; |
419 | if (@_) { |
420 | while (@_) { |
421 | $i = shift; |
422 | $i = _find_subline($i) if ($i =~ /\D/); |
423 | $s->output("Subroutine not found.\n") unless $i; |
424 | if (defined $DB::dbline{$i}) { |
425 | $DB::dbline{$i} =~ s/^[^\0]+//; |
426 | if ($DB::dbline{$i} =~ s/^\0?$//) { |
427 | delete $DB::dbline{$i}; |
428 | } |
429 | } |
430 | } |
431 | } |
432 | else { |
433 | for ($i = 1; $i <= $#DB::dbline ; $i++) { |
434 | if (defined $DB::dbline{$i}) { |
435 | $DB::dbline{$i} =~ s/^[^\0]+//; |
436 | if ($DB::dbline{$i} =~ s/^\0?$//) { |
437 | delete $DB::dbline{$i}; |
438 | } |
439 | } |
440 | } |
441 | } |
442 | } |
443 | |
444 | sub set_action { |
445 | my $s = shift; |
446 | my $i = shift; |
447 | my $act = shift; |
448 | $i = _find_subline($i) if ($i =~ /\D/); |
449 | $s->output("Subroutine not found.\n") unless $i; |
450 | if ($i) { |
451 | if ($DB::dbline[$i] == 0) { |
452 | $s->output("Line $i not actionable.\n"); |
453 | } |
454 | else { |
455 | $DB::dbline{$i} =~ s/\0[^\0]*//; |
456 | $DB::dbline{$i} .= "\0" . $act; |
457 | } |
458 | } |
459 | } |
460 | |
461 | sub clr_actions { |
462 | my $s = shift; |
463 | my $i; |
464 | if (@_) { |
465 | while (@_) { |
466 | my $i = shift; |
467 | $i = _find_subline($i) if ($i =~ /\D/); |
468 | $s->output("Subroutine not found.\n") unless $i; |
469 | if ($i && $DB::dbline[$i] != 0) { |
470 | $DB::dbline{$i} =~ s/\0[^\0]*//; |
471 | delete $DB::dbline{$i} if $DB::dbline{$i} =~ s/^\0?$//; |
472 | } |
473 | } |
474 | } |
475 | else { |
476 | for ($i = 1; $i <= $#DB::dbline ; $i++) { |
477 | if (defined $DB::dbline{$i}) { |
478 | $DB::dbline{$i} =~ s/\0[^\0]*//; |
479 | delete $DB::dbline{$i} if $DB::dbline{$i} =~ s/^\0?$//; |
480 | } |
481 | } |
482 | } |
483 | } |
484 | |
485 | sub prestop { |
486 | my ($client, $val) = @_; |
487 | return defined($val) ? $preeval->{$client} = $val : $preeval->{$client}; |
488 | } |
489 | |
490 | sub poststop { |
491 | my ($client, $val) = @_; |
492 | return defined($val) ? $posteval->{$client} = $val : $posteval->{$client}; |
493 | } |
494 | |
495 | # |
496 | # "pure virtual" methods |
497 | # |
498 | |
499 | # client-specific pre/post-stop actions. |
500 | sub cprestop {} |
501 | sub cpoststop {} |
502 | |
503 | # client complete startup |
504 | sub awaken {} |
505 | |
506 | sub skippkg { |
507 | my $s = shift; |
508 | push @skippkg, @_ if @_; |
509 | } |
510 | |
511 | sub evalcode { |
512 | my ($client, $val) = @_; |
513 | if (defined $val) { |
514 | $running = 2; # hand over to DB() to evaluate in its context |
515 | $ineval->{$client} = $val; |
516 | } |
517 | return $ineval->{$client}; |
518 | } |
519 | |
520 | sub ready { |
521 | my $s = shift; |
522 | return $ready = 1; |
523 | } |
524 | |
525 | # stubs |
526 | |
527 | sub init {} |
528 | sub stop {} |
529 | sub idle {} |
530 | sub cleanup {} |
531 | sub output {} |
532 | |
533 | # |
534 | # client init |
535 | # |
536 | for (@clients) { $_->init } |
537 | |
538 | $SIG{'INT'} = \&DB::catch; |
539 | |
540 | # disable this if stepping through END blocks is desired |
541 | # (looks scary and deconstructivist with Swat) |
542 | END { $ready = 0 } |
543 | |
544 | 1; |
545 | __END__ |
546 | |
547 | =head1 NAME |
548 | |
549 | DB - programmatic interface to the Perl debugging API (draft, subject to |
550 | change) |
551 | |
552 | =head1 SYNOPSIS |
553 | |
554 | package CLIENT; |
555 | use DB; |
556 | @ISA = qw(DB); |
3cb6de81 |
557 | |
43d8869b |
558 | # these (inherited) methods can be called by the client |
3cb6de81 |
559 | |
43d8869b |
560 | CLIENT->register() # register a client package name |
561 | CLIENT->done() # de-register from the debugging API |
562 | CLIENT->skippkg('hide::hide') # ask DB not to stop in this package |
563 | CLIENT->cont([WHERE]) # run some more (until BREAK or another breakpt) |
564 | CLIENT->step() # single step |
565 | CLIENT->next() # step over |
566 | CLIENT->ret() # return from current subroutine |
567 | CLIENT->backtrace() # return the call stack description |
568 | CLIENT->ready() # call when client setup is done |
569 | CLIENT->trace_toggle() # toggle subroutine call trace mode |
570 | CLIENT->subs([SUBS]) # return subroutine information |
571 | CLIENT->files() # return list of all files known to DB |
572 | CLIENT->lines() # return lines in currently loaded file |
573 | CLIENT->loadfile(FILE,LINE) # load a file and let other clients know |
574 | CLIENT->lineevents() # return info on lines with actions |
575 | CLIENT->set_break([WHERE],[COND]) |
576 | CLIENT->set_tbreak([WHERE]) |
577 | CLIENT->clr_breaks([LIST]) |
578 | CLIENT->set_action(WHERE,ACTION) |
579 | CLIENT->clr_actions([LIST]) |
580 | CLIENT->evalcode(STRING) # eval STRING in executing code's context |
581 | CLIENT->prestop([STRING]) # execute in code context before stopping |
582 | CLIENT->poststop([STRING])# execute in code context before resuming |
583 | |
584 | # These methods will be called at the appropriate times. |
585 | # Stub versions provided do nothing. |
586 | # None of these can block. |
3cb6de81 |
587 | |
43d8869b |
588 | CLIENT->init() # called when debug API inits itself |
589 | CLIENT->stop(FILE,LINE) # when execution stops |
590 | CLIENT->idle() # while stopped (can be a client event loop) |
591 | CLIENT->cleanup() # just before exit |
592 | CLIENT->output(LIST) # called to print any output that API must show |
593 | |
594 | =head1 DESCRIPTION |
595 | |
596 | Perl debug information is frequently required not just by debuggers, |
597 | but also by modules that need some "special" information to do their |
598 | job properly, like profilers. |
599 | |
600 | This module abstracts and provides all of the hooks into Perl internal |
601 | debugging functionality, so that various implementations of Perl debuggers |
602 | (or packages that want to simply get at the "privileged" debugging data) |
603 | can all benefit from the development of this common code. Currently used |
604 | by Swat, the perl/Tk GUI debugger. |
605 | |
606 | Note that multiple "front-ends" can latch into this debugging API |
607 | simultaneously. This is intended to facilitate things like |
608 | debugging with a command line and GUI at the same time, debugging |
609 | debuggers etc. [Sounds nice, but this needs some serious support -- GSAR] |
610 | |
611 | In particular, this API does B<not> provide the following functions: |
612 | |
613 | =over 4 |
614 | |
615 | =item * |
616 | |
617 | data display |
618 | |
619 | =item * |
620 | |
621 | command processing |
622 | |
623 | =item * |
624 | |
625 | command alias management |
626 | |
627 | =item * |
628 | |
629 | user interface (tty or graphical) |
630 | |
631 | =back |
632 | |
633 | These are intended to be services performed by the clients of this API. |
634 | |
635 | This module attempts to be squeaky clean w.r.t C<use strict;> and when |
636 | warnings are enabled. |
637 | |
638 | |
639 | =head2 Global Variables |
640 | |
641 | The following "public" global names can be read by clients of this API. |
642 | Beware that these should be considered "readonly". |
643 | |
644 | =over 8 |
645 | |
646 | =item $DB::sub |
647 | |
648 | Name of current executing subroutine. |
649 | |
650 | =item %DB::sub |
651 | |
652 | The keys of this hash are the names of all the known subroutines. Each value |
653 | is an encoded string that has the sprintf(3) format |
654 | C<("%s:%d-%d", filename, fromline, toline)>. |
655 | |
656 | =item $DB::single |
657 | |
658 | Single-step flag. Will be true if the API will stop at the next statement. |
659 | |
660 | =item $DB::signal |
661 | |
662 | Signal flag. Will be set to a true value if a signal was caught. Clients may |
663 | check for this flag to abort time-consuming operations. |
664 | |
665 | =item $DB::trace |
666 | |
667 | This flag is set to true if the API is tracing through subroutine calls. |
668 | |
669 | =item @DB::args |
670 | |
671 | Contains the arguments of current subroutine, or the C<@ARGV> array if in the |
672 | toplevel context. |
673 | |
674 | =item @DB::dbline |
675 | |
676 | List of lines in currently loaded file. |
677 | |
678 | =item %DB::dbline |
679 | |
680 | Actions in current file (keys are line numbers). The values are strings that |
681 | have the sprintf(3) format C<("%s\000%s", breakcondition, actioncode)>. |
682 | |
683 | =item $DB::package |
684 | |
685 | Package namespace of currently executing code. |
686 | |
687 | =item $DB::filename |
688 | |
689 | Currently loaded filename. |
690 | |
691 | =item $DB::subname |
692 | |
693 | Fully qualified name of currently executing subroutine. |
694 | |
695 | =item $DB::lineno |
696 | |
697 | Line number that will be executed next. |
698 | |
699 | =back |
700 | |
701 | =head2 API Methods |
702 | |
703 | The following are methods in the DB base class. A client must |
704 | access these methods by inheritance (*not* by calling them directly), |
705 | since the API keeps track of clients through the inheritance |
706 | mechanism. |
707 | |
708 | =over 8 |
709 | |
710 | =item CLIENT->register() |
711 | |
712 | register a client object/package |
713 | |
714 | =item CLIENT->evalcode(STRING) |
715 | |
716 | eval STRING in executing code context |
717 | |
718 | =item CLIENT->skippkg('D::hide') |
719 | |
720 | ask DB not to stop in these packages |
721 | |
722 | =item CLIENT->run() |
723 | |
724 | run some more (until a breakpt is reached) |
725 | |
726 | =item CLIENT->step() |
727 | |
728 | single step |
729 | |
730 | =item CLIENT->next() |
731 | |
732 | step over |
733 | |
734 | =item CLIENT->done() |
735 | |
736 | de-register from the debugging API |
737 | |
738 | =back |
739 | |
740 | =head2 Client Callback Methods |
741 | |
742 | The following "virtual" methods can be defined by the client. They will |
743 | be called by the API at appropriate points. Note that unless specified |
744 | otherwise, the debug API only defines empty, non-functional default versions |
745 | of these methods. |
746 | |
747 | =over 8 |
748 | |
749 | =item CLIENT->init() |
750 | |
751 | Called after debug API inits itself. |
752 | |
753 | =item CLIENT->prestop([STRING]) |
754 | |
755 | Usually inherited from DB package. If no arguments are passed, |
756 | returns the prestop action string. |
757 | |
758 | =item CLIENT->stop() |
759 | |
760 | Called when execution stops (w/ args file, line). |
761 | |
762 | =item CLIENT->idle() |
763 | |
764 | Called while stopped (can be a client event loop). |
765 | |
766 | =item CLIENT->poststop([STRING]) |
767 | |
768 | Usually inherited from DB package. If no arguments are passed, |
769 | returns the poststop action string. |
770 | |
771 | =item CLIENT->evalcode(STRING) |
772 | |
773 | Usually inherited from DB package. Ask for a STRING to be C<eval>-ed |
774 | in executing code context. |
775 | |
776 | =item CLIENT->cleanup() |
777 | |
778 | Called just before exit. |
779 | |
780 | =item CLIENT->output(LIST) |
781 | |
782 | Called when API must show a message (warnings, errors etc.). |
783 | |
784 | |
785 | =back |
786 | |
787 | |
788 | =head1 BUGS |
789 | |
790 | The interface defined by this module is missing some of the later additions |
791 | to perl's debugging functionality. As such, this interface should be considered |
792 | highly experimental and subject to change. |
793 | |
794 | =head1 AUTHOR |
795 | |
6e238990 |
796 | Gurusamy Sarathy gsar@activestate.com |
43d8869b |
797 | |
798 | This code heavily adapted from an early version of perl5db.pl attributable |
799 | to Larry Wall and the Perl Porters. |
800 | |
801 | =cut |