3 ;;;; This software is part of the SBCL system. See the README file for
6 ;;;; This software is derived from the CMU CL system, which was
7 ;;;; written at Carnegie Mellon University and released into the
8 ;;;; public domain. The software is in the public domain and is
9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
10 ;;;; files for more information.
12 (in-package "SB!DEBUG")
14 ;;;; variables and constants
16 ;;; things to consider when tweaking these values:
17 ;;; * We're afraid to just default them to NIL and NIL, in case the
18 ;;; user inadvertently causes a hairy data structure to be printed
19 ;;; when he inadvertently enters the debugger.
20 ;;; * We don't want to truncate output too much. These days anyone
21 ;;; can easily run their Lisp in a windowing system or under Emacs,
22 ;;; so it's not the end of the world even if the worst case is a
23 ;;; few thousand lines of output.
24 ;;; * As condition :REPORT methods are converted to use the pretty
25 ;;; printer, they acquire *PRINT-LEVEL* constraints, so e.g. under
26 ;;; sbcl-0.7.1.28's old value of *DEBUG-PRINT-LEVEL*=3, an
27 ;;; ARG-COUNT-ERROR printed as
28 ;;; error while parsing arguments to DESTRUCTURING-BIND:
29 ;;; invalid number of elements in
31 ;;; to satisfy lambda list
33 ;;; exactly 2 expected, but 5 found
34 (defvar *debug-print-level* 5
36 "*PRINT-LEVEL* for the debugger")
37 (defvar *debug-print-length* 7
39 "*PRINT-LENGTH* for the debugger")
41 (defvar *debug-readtable*
42 ;; KLUDGE: This can't be initialized in a cold toplevel form,
43 ;; because the *STANDARD-READTABLE* isn't initialized until after
44 ;; cold toplevel forms have run. So instead we initialize it
45 ;; immediately after *STANDARD-READTABLE*. -- WHN 20000205
48 "*READTABLE* for the debugger")
50 (defvar *in-the-debugger* nil
52 "This is T while in the debugger.")
54 ;;; nestedness inside debugger command loops
55 (defvar *debug-command-level* 0)
57 ;;; If this is bound before the debugger is invoked, it is used as the
58 ;;; stack top by the debugger.
59 (defvar *stack-top-hint* nil)
61 (defvar *stack-top* nil)
62 (defvar *real-stack-top* nil)
64 (defvar *current-frame* nil)
66 ;;; Beginner-oriented help messages are important because you end up
67 ;;; in the debugger whenever something bad happens, or if you try to
68 ;;; get out of the system with Ctrl-C or (EXIT) or EXIT or whatever.
69 ;;; But after memorizing them the wasted screen space gets annoying..
70 (defvar *debug-beginner-help-p* t
71 "Should the debugger display beginner-oriented help messages?")
73 (defun debug-prompt (stream)
76 (sb!di:frame-number *current-frame*)
77 (> *debug-command-level* 1)
78 *debug-command-level*))
80 (defparameter *debug-help-string*
81 "The debug prompt is square brackets, with number(s) indicating the current
82 control stack level and, if you've entered the debugger recursively, how
83 deeply recursed you are.
84 Any command -- including the name of a restart -- may be uniquely abbreviated.
85 The debugger rebinds various special variables for controlling i/o, sometimes
86 to defaults (much like WITH-STANDARD-IO-SYNTAX does) and sometimes to
87 its own special values, e.g. SB-DEBUG:*DEBUG-PRINT-LEVEL*.
88 Debug commands do not affect *, //, and similar variables, but evaluation in
89 the debug loop does affect these variables.
90 SB-DEBUG:*FLUSH-DEBUG-ERRORS* controls whether errors at the debug prompt
91 drop you deeper into the debugger.
93 Getting in and out of the debugger:
94 RESTART invokes restart numbered as shown (prompt if not given).
95 ERROR prints the error condition and restart cases.
96 The number of any restart, or its name, or a unique abbreviation for its
97 name, is a valid command, and is the same as using RESTART to invoke
101 U up frame D down frame
102 B bottom frame F n frame n (n=0 for top frame)
105 BACKTRACE [n] shows n frames going down the stack.
106 LIST-LOCALS, L lists locals in current function.
107 PRINT, P displays current function call.
108 SOURCE [n] displays frame's source form with n levels of enclosing forms.
110 Breakpoints and steps:
111 LIST-LOCATIONS [{function | :C}] List the locations for breakpoints.
112 Specify :C for the current frame.
114 LIST-BREAKPOINTS List the active breakpoints.
115 Abbreviations: LB, LBP
116 DELETE-BREAKPOINT [n] Remove breakpoint n or all breakpoints.
117 Abbreviations: DEL, DBP
118 BREAKPOINT {n | :end | :start} [:break form] [:function function]
119 [{:print form}*] [:condition form]
121 Abbreviations: BR, BP
122 STEP [n] Step to the next location or step n times.
124 Function and macro commands:
125 (SB-DEBUG:DEBUG-RETURN expression)
126 Exit the debugger, returning expression's values from the current frame.
128 Return the n'th argument in the current frame.
129 (SB-DEBUG:VAR string-or-symbol [id])
130 Returns the value of the specified variable in the current frame.
133 SLURP Discard all pending input on *STANDARD-INPUT*. (This can be
134 useful when the debugger was invoked to handle an error in
135 deeply nested input syntax, and now the reader is confused.)")
137 ;;; This is used to communicate to DEBUG-LOOP that we are at a step breakpoint.
138 (define-condition step-condition (simple-condition) ())
140 ;;;; breakpoint state
142 (defvar *only-block-start-locations* nil
144 "When true, the LIST-LOCATIONS command only displays block start locations.
145 Otherwise, all locations are displayed.")
147 (defvar *print-location-kind* nil
149 "When true, list the code location type in the LIST-LOCATIONS command.")
151 ;;; a list of the types of code-locations that should not be stepped
152 ;;; to and should not be listed when listing breakpoints
153 (defvar *bad-code-location-types* '(:call-site :internal-error))
154 (declaim (type list *bad-code-location-types*))
156 ;;; code locations of the possible breakpoints
157 (defvar *possible-breakpoints*)
158 (declaim (type list *possible-breakpoints*))
160 ;;; a list of the made and active breakpoints, each is a
161 ;;; BREAKPOINT-INFO structure
162 (defvar *breakpoints* nil)
163 (declaim (type list *breakpoints*))
165 ;;; a list of BREAKPOINT-INFO structures of the made and active step
167 (defvar *step-breakpoints* nil)
168 (declaim (type list *step-breakpoints*))
170 ;;; the number of times left to step
171 (defvar *number-of-steps* 1)
172 (declaim (type integer *number-of-steps*))
174 ;;; This is used when listing and setting breakpoints.
175 (defvar *default-breakpoint-debug-fun* nil)
176 (declaim (type (or list sb!di:debug-fun) *default-breakpoint-debug-fun*))
178 ;;;; code location utilities
180 ;;; Return the first code-location in the passed debug block.
181 (defun first-code-location (debug-block)
183 (first-code-location nil))
184 (sb!di:do-debug-block-locations (code-location debug-block)
186 (setf first-code-location code-location)
188 first-code-location))
190 ;;; Return a list of the next code-locations following the one passed.
191 ;;; One of the *BAD-CODE-LOCATION-TYPES* will not be returned.
192 (defun next-code-locations (code-location)
193 (let ((debug-block (sb!di:code-location-debug-block code-location))
194 (block-code-locations nil))
195 (sb!di:do-debug-block-locations (block-code-location debug-block)
196 (unless (member (sb!di:code-location-kind block-code-location)
197 *bad-code-location-types*)
198 (push block-code-location block-code-locations)))
199 (setf block-code-locations (nreverse block-code-locations))
200 (let* ((code-loc-list (rest (member code-location block-code-locations
201 :test #'sb!di:code-location=)))
202 (next-list (cond (code-loc-list
203 (list (first code-loc-list)))
204 ((map 'list #'first-code-location
205 (sb!di:debug-block-successors debug-block)))
207 (when (and (= (length next-list) 1)
208 (sb!di:code-location= (first next-list) code-location))
209 (setf next-list (next-code-locations (first next-list))))
212 ;;; Return a list of code-locations of the possible breakpoints of DEBUG-FUN.
213 (defun possible-breakpoints (debug-fun)
214 (let ((possible-breakpoints nil))
215 (sb!di:do-debug-fun-blocks (debug-block debug-fun)
216 (unless (sb!di:debug-block-elsewhere-p debug-block)
217 (if *only-block-start-locations*
218 (push (first-code-location debug-block) possible-breakpoints)
219 (sb!di:do-debug-block-locations (code-location debug-block)
220 (when (not (member (sb!di:code-location-kind code-location)
221 *bad-code-location-types*))
222 (push code-location possible-breakpoints))))))
223 (nreverse possible-breakpoints)))
225 ;;; Search the info-list for the item passed (CODE-LOCATION,
226 ;;; DEBUG-FUN, or BREAKPOINT-INFO). If the item passed is a debug
227 ;;; function then kind will be compared if it was specified. The kind
228 ;;; if also compared if a breakpoint-info is passed since it's in the
229 ;;; breakpoint. The info structure is returned if found.
230 (defun location-in-list (place info-list &optional (kind nil))
231 (when (breakpoint-info-p place)
232 (setf kind (sb!di:breakpoint-kind (breakpoint-info-breakpoint place)))
233 (setf place (breakpoint-info-place place)))
234 (cond ((sb!di:code-location-p place)
235 (find place info-list
236 :key #'breakpoint-info-place
237 :test (lambda (x y) (and (sb!di:code-location-p y)
238 (sb!di:code-location= x y)))))
240 (find place info-list
241 :test (lambda (x-debug-fun y-info)
242 (let ((y-place (breakpoint-info-place y-info))
243 (y-breakpoint (breakpoint-info-breakpoint
245 (and (sb!di:debug-fun-p y-place)
246 (eq x-debug-fun y-place)
248 (eq kind (sb!di:breakpoint-kind
249 y-breakpoint))))))))))
251 ;;; If LOC is an unknown location, then try to find the block start
252 ;;; location. Used by source printing to some information instead of
253 ;;; none for the user.
254 (defun maybe-block-start-location (loc)
255 (if (sb!di:code-location-unknown-p loc)
256 (let* ((block (sb!di:code-location-debug-block loc))
257 (start (sb!di:do-debug-block-locations (loc block)
259 (cond ((and (not (sb!di:debug-block-elsewhere-p block))
261 ;; FIXME: Why output on T instead of *DEBUG-FOO* or something?
262 (format t "~%unknown location: using block start~%")
268 ;;;; the BREAKPOINT-INFO structure
270 ;;; info about a made breakpoint
271 (defstruct (breakpoint-info (:copier nil)
272 (:constructor %make-breakpoint-info))
273 ;; where we are going to stop
275 :type (or sb!di:code-location sb!di:debug-fun)
277 ;; the breakpoint returned by SB!DI:MAKE-BREAKPOINT
278 (breakpoint (missing-arg) :type sb!di:breakpoint :read-only t)
279 ;; the function returned from SB!DI:PREPROCESS-FOR-EVAL. If result is
280 ;; non-NIL, drop into the debugger.
281 (break #'identity :type function :read-only t)
282 ;; the function returned from SB!DI:PREPROCESS-FOR-EVAL. If result is
283 ;; non-NIL, eval (each) print and print results.
284 (condition #'identity :type function :read-only t)
285 ;; the list of functions from SB!DI:PREPROCESS-FOR-EVAL to evaluate.
286 ;; Results are conditionally printed. CAR of each element is the
287 ;; function, CDR is the form it goes with.
288 (print nil :type list :read-only t)
289 ;; the number used when listing the possible breakpoints within a
290 ;; function; or could also be a symbol such as START or END
291 (code-location-selector (missing-arg) :type (or symbol integer) :read-only t)
292 ;; the number used when listing the active breakpoints, and when
293 ;; deleting breakpoints
294 (breakpoint-number (missing-arg) :type integer :read-only t))
296 (defun create-breakpoint-info (place breakpoint code-location-selector
297 &key (break #'identity)
298 (condition #'identity) (print nil))
300 (sort *breakpoints* #'< :key #'breakpoint-info-breakpoint-number))
301 (let ((breakpoint-number
302 (do ((i 1 (incf i)) (breakpoints *breakpoints* (rest breakpoints)))
303 ((or (> i (length *breakpoints*))
304 (not (= i (breakpoint-info-breakpoint-number
305 (first breakpoints)))))
308 (%make-breakpoint-info :place place
309 :breakpoint breakpoint
310 :code-location-selector code-location-selector
311 :breakpoint-number breakpoint-number
316 (defun print-breakpoint-info (breakpoint-info)
317 (let ((place (breakpoint-info-place breakpoint-info))
318 (bp-number (breakpoint-info-breakpoint-number breakpoint-info)))
319 (case (sb!di:breakpoint-kind (breakpoint-info-breakpoint breakpoint-info))
321 (print-code-location-source-form place 0)
325 (breakpoint-info-code-location-selector breakpoint-info)
326 (sb!di:debug-fun-name (sb!di:code-location-debug-fun place))))
328 (format t "~&~S: FUN-START in ~S" bp-number
329 (sb!di:debug-fun-name place)))
331 (format t "~&~S: FUN-END in ~S" bp-number
332 (sb!di:debug-fun-name place))))))
334 ;;;; MAIN-HOOK-FUN for steps and breakpoints
336 ;;; This must be passed as the hook function. It keeps track of where
337 ;;; STEP breakpoints are.
338 (defun main-hook-fun (current-frame breakpoint &optional return-vals
340 (setf *default-breakpoint-debug-fun*
341 (sb!di:frame-debug-fun current-frame))
342 (dolist (step-info *step-breakpoints*)
343 (sb!di:delete-breakpoint (breakpoint-info-breakpoint step-info))
344 (let ((bp-info (location-in-list step-info *breakpoints*)))
346 (sb!di:activate-breakpoint (breakpoint-info-breakpoint bp-info)))))
347 (let ((*stack-top-hint* current-frame)
349 (location-in-list (sb!di:breakpoint-what breakpoint)
351 (sb!di:breakpoint-kind breakpoint)))
353 (location-in-list (sb!di:breakpoint-what breakpoint)
355 (sb!di:breakpoint-kind breakpoint)))
359 (setf *step-breakpoints* nil)
360 (labels ((build-string (str)
361 (setf string (concatenate 'string string str)))
362 (print-common-info ()
364 (with-output-to-string (*standard-output*)
366 (format t "~%Return values: ~S" return-vals))
368 (when (breakpoint-info-print bp-hit-info)
370 (print-frame-call current-frame))
371 (dolist (print (breakpoint-info-print bp-hit-info))
372 (format t "~& ~S = ~S" (rest print)
373 (funcall (first print) current-frame))))))))
375 (setf break (funcall (breakpoint-info-break bp-hit-info)
377 (setf condition (funcall (breakpoint-info-condition bp-hit-info)
379 (cond ((and bp-hit-info step-hit-info (= 1 *number-of-steps*))
380 (build-string (format nil "~&*Step (to a breakpoint)*"))
383 ((and bp-hit-info step-hit-info break)
384 (build-string (format nil "~&*Step (to a breakpoint)*"))
387 ((and bp-hit-info step-hit-info)
389 (format t "~A" string)
390 (decf *number-of-steps*)
391 (set-step-breakpoint current-frame))
392 ((and step-hit-info (= 1 *number-of-steps*))
393 (build-string "*Step*")
394 (break (make-condition 'step-condition :format-control string)))
396 (decf *number-of-steps*)
397 (set-step-breakpoint current-frame))
400 (build-string (format nil "~&*Breakpoint hit*")))
404 (format t "~A" string)))
406 (break "unknown breakpoint"))))))
408 ;;; Set breakpoints at the next possible code-locations. After calling
409 ;;; this, either (CONTINUE) if in the debugger or just let program flow
410 ;;; return if in a hook function.
411 (defun set-step-breakpoint (frame)
413 ((sb!di:debug-block-elsewhere-p (sb!di:code-location-debug-block
414 (sb!di:frame-code-location frame)))
415 ;; FIXME: FORMAT T is used for error output here and elsewhere in
417 (format t "cannot step, in elsewhere code~%"))
419 (let* ((code-location (sb!di:frame-code-location frame))
420 (next-code-locations (next-code-locations code-location)))
423 (dolist (code-location next-code-locations)
424 (let ((bp-info (location-in-list code-location *breakpoints*)))
426 (sb!di:deactivate-breakpoint (breakpoint-info-breakpoint
428 (let ((bp (sb!di:make-breakpoint #'main-hook-fun code-location
429 :kind :code-location)))
430 (sb!di:activate-breakpoint bp)
431 (push (create-breakpoint-info code-location bp 0)
432 *step-breakpoints*))))
434 (let* ((debug-fun (sb!di:frame-debug-fun *current-frame*))
435 (bp (sb!di:make-breakpoint #'main-hook-fun debug-fun
437 (sb!di:activate-breakpoint bp)
438 (push (create-breakpoint-info debug-fun bp 0)
439 *step-breakpoints*))))))))
443 ;;; ANSI specifies that this macro shall exist, even if only as a
444 ;;; trivial placeholder like this.
445 (defmacro step (form)
446 "a trivial placeholder implementation of the CL:STEP macro required by
453 (defun backtrace (&optional (count most-positive-fixnum)
454 (*standard-output* *debug-io*))
456 "Show a listing of the call stack going down from the current frame. In the
457 debugger, the current frame is indicated by the prompt. COUNT is how many
459 (fresh-line *standard-output*)
460 (do ((frame (if *in-the-debugger* *current-frame* (sb!di:top-frame))
461 (sb!di:frame-down frame))
462 (count count (1- count)))
463 ((or (null frame) (zerop count)))
464 (print-frame-call frame :number t))
465 (fresh-line *standard-output*)
468 (defun backtrace-as-list (&optional (count most-positive-fixnum))
469 #!+sb-doc "Return a list representing the current BACKTRACE."
470 (do ((reversed-result nil)
471 (frame (if *in-the-debugger* *current-frame* (sb!di:top-frame))
472 (sb!di:frame-down frame))
473 (count count (1- count)))
474 ((or (null frame) (zerop count))
475 (nreverse reversed-result))
476 (push (frame-call-as-list frame) reversed-result)))
478 (defun frame-call-as-list (frame)
479 (cons (sb!di:debug-fun-name (sb!di:frame-debug-fun frame))
480 (frame-args-as-list frame)))
484 (eval-when (:compile-toplevel :execute)
486 ;;; This is a convenient way to express what to do for each type of
487 ;;; lambda-list element.
488 (sb!xc:defmacro lambda-list-element-dispatch (element
499 (ecase (car ,element)
500 (:optional ,@optional)
502 (:keyword ,@keyword)))
504 (aver (eq ,element :deleted))
507 (sb!xc:defmacro lambda-var-dispatch (variable location deleted valid other)
508 (let ((var (gensym)))
509 `(let ((,var ,variable))
510 (cond ((eq ,var :deleted) ,deleted)
511 ((eq (sb!di:debug-var-validity ,var ,location) :valid)
517 ;;; This is used in constructing arg lists for debugger printing when
518 ;;; the arg list is unavailable, some arg is unavailable or unused, etc.
519 (defstruct (unprintable-object
520 (:constructor make-unprintable-object (string))
521 (:print-object (lambda (x s)
522 (print-unreadable-object (x s)
523 (write-string (unprintable-object-string x)
528 ;;; Extract the function argument values for a debug frame.
529 (defun frame-args-as-list (frame)
530 (let ((debug-fun (sb!di:frame-debug-fun frame))
531 (loc (sb!di:frame-code-location frame))
532 (reversed-result nil))
535 (dolist (ele (sb!di:debug-fun-lambda-list debug-fun))
536 (lambda-list-element-dispatch ele
537 :required ((push (frame-call-arg ele loc frame) reversed-result))
538 :optional ((push (frame-call-arg (second ele) loc frame)
540 :keyword ((push (second ele) reversed-result)
541 (push (frame-call-arg (third ele) loc frame)
543 :deleted ((push (frame-call-arg ele loc frame) reversed-result))
544 :rest ((lambda-var-dispatch (second ele) loc
547 (setf reversed-result
548 (append (reverse (sb!di:debug-var-value
552 (push (make-unprintable-object
553 "unavailable &REST argument")
555 ;; As long as we do an ordinary return (as opposed to SIGNALing
556 ;; a CONDITION) from the DOLIST above:
557 (nreverse reversed-result))
558 (sb!di:lambda-list-unavailable
560 (make-unprintable-object "unavailable lambda list")))))
562 ;;; Print FRAME with verbosity level 1. If we hit a &REST arg, then
563 ;;; print as many of the values as possible, punting the loop over
564 ;;; lambda-list variables since any other arguments will be in the
565 ;;; &REST arg's list of values.
566 (defun print-frame-call-1 (frame)
567 (let ((debug-fun (sb!di:frame-debug-fun frame)))
569 (pprint-logical-block (*standard-output* nil :prefix "(" :suffix ")")
570 (let ((args (ensure-printable-object (frame-args-as-list frame))))
571 ;; Since we go to some trouble to make nice informative function
572 ;; names like (PRINT-OBJECT :AROUND (CLOWN T)), let's make sure
573 ;; that they aren't truncated by *PRINT-LENGTH* and *PRINT-LEVEL*.
574 (let ((*print-length* nil)
576 (prin1 (ensure-printable-object (sb!di:debug-fun-name debug-fun))))
577 ;; For the function arguments, we can just print normally.
579 (format t "~{ ~_~S~}" args)
580 (format t " ~S" args))))
582 (when (sb!di:debug-fun-kind debug-fun)
584 (prin1 (sb!di:debug-fun-kind debug-fun))
587 (defun ensure-printable-object (object)
589 (with-open-stream (out (make-broadcast-stream))
593 (declare (ignore cond))
594 (make-unprintable-object "error printing object"))))
596 (defun frame-call-arg (var location frame)
597 (lambda-var-dispatch var location
598 (make-unprintable-object "unused argument")
599 (sb!di:debug-var-value var frame)
600 (make-unprintable-object "unavailable argument")))
602 ;;; Prints a representation of the function call causing FRAME to
603 ;;; exist. VERBOSITY indicates the level of information to output;
604 ;;; zero indicates just printing the DEBUG-FUN's name, and one
605 ;;; indicates displaying call-like, one-liner format with argument
607 (defun print-frame-call (frame &key (verbosity 1) (number nil))
611 (format t "~&~S: " (sb!di:frame-number frame)))
612 (format t "~S" frame))
615 (format t "~&~S: " (sb!di:frame-number frame)))
616 (print-frame-call-1 frame)))
617 (when (>= verbosity 2)
618 (let ((loc (sb!di:frame-code-location frame)))
621 (sb!di:code-location-debug-block loc)
622 (format t "~%source: ")
623 (print-code-location-source-form loc 0))
624 (sb!di:debug-condition (ignore) ignore)
625 (error (c) (format t "error finding source: ~A" c))))))
629 (defvar *debugger-hook* nil
631 "This is either NIL or a function of two arguments, a condition and the value
632 of *DEBUGGER-HOOK*. This function can either handle the condition or return
633 which causes the standard debugger to execute. The system passes the value
634 of this variable to the function because it binds *DEBUGGER-HOOK* to NIL
635 around the invocation.")
637 ;;; These are bound on each invocation of INVOKE-DEBUGGER.
638 (defvar *debug-restarts*)
639 (defvar *debug-condition*)
640 (defvar *nested-debug-condition*)
642 (defun invoke-debugger (condition)
644 "Enter the debugger."
645 (let ((old-hook *debugger-hook*))
647 (let ((*debugger-hook* nil))
648 (funcall old-hook condition old-hook))))
650 ;; Note: CMU CL had (SB-UNIX:UNIX-SIGSETMASK 0) here. I deleted it
651 ;; around sbcl-0.7.8.5 (by which time it had mutated to have a
652 ;; #!-SUNOS prefix and a FIXME note observing that it wasn't needed
653 ;; on SunOS and no one knew why it was needed anywhere else either).
654 ;; So if something mysteriously breaks that has worked since the CMU
655 ;; CL days, that might be why. -- WHN 2002-09-28
657 ;; We definitely want *PACKAGE* to be of valid type.
659 ;; Elsewhere in the system, we use the SANE-PACKAGE function for
660 ;; this, but here causing an exception just as we're trying to handle
661 ;; an exception would be confusing, so instead we use a special hack.
662 (unless (and (packagep *package*)
663 (package-name *package*))
664 (setf *package* (find-package :cl-user))
665 (format *error-output*
666 "The value of ~S was not an undeleted PACKAGE. It has been
668 '*package* *package*))
670 ;; Try to force the other special variables into a useful state.
671 (let (;; Protect from WITH-STANDARD-IO-SYNTAX some variables where
672 ;; any default we might use is less useful than just reusing
673 ;; the global values.
674 (original-package *package*)
675 (original-print-pretty *print-pretty*))
676 (with-standard-io-syntax
677 (let ((*debug-condition* condition)
678 (*debug-restarts* (compute-restarts condition))
679 (*nested-debug-condition* nil)
680 ;; We want the printer and reader to be in a useful state,
681 ;; regardless of where the debugger was invoked in the
682 ;; program. WITH-STANDARD-IO-SYNTAX did much of what we
684 ;; * It doesn't affect our internal special variables
685 ;; like *CURRENT-LEVEL-IN-PRINT*.
686 ;; * It isn't customizable.
687 ;; * It doesn't set *PRINT-READABLY* to the same value
688 ;; as the toplevel default.
689 ;; * It sets *PACKAGE* to COMMON-LISP-USER, which is not
690 ;; helpful behavior for a debugger.
691 ;; * There's no particularly good debugger default for
692 ;; *PRINT-PRETTY*, since T is usually what you want
693 ;; -- except absolutely not what you want when you're
694 ;; debugging failures in PRINT-OBJECT logic.
695 ;; We try to address all these issues with explicit
697 (sb!kernel:*current-level-in-print* 0)
698 (*print-length* *debug-print-length*)
699 (*print-level* *debug-print-level*)
700 (*readtable* *debug-readtable*)
701 (*print-readably* nil)
702 (*package* original-package)
703 (*print-pretty* original-print-pretty))
705 ;; Before we start our own output, finish any pending output.
706 ;; Otherwise, if the user tried to track the progress of his
707 ;; program using PRINT statements, he'd tend to lose the last
708 ;; line of output or so, which'd be confusing.
709 (flush-standard-output-streams)
711 ;; (The initial output here goes to *ERROR-OUTPUT*, because the
712 ;; initial output is not interactive, just an error message,
713 ;; and when people redirect *ERROR-OUTPUT*, they could
714 ;; reasonably expect to see error messages logged there,
715 ;; regardless of what the debugger does afterwards.)
717 (format *error-output*
718 "~2&~@<debugger invoked on condition of type ~S: ~
720 (type-of *debug-condition*)
723 (setf *nested-debug-condition* condition)
724 (let ((ndc-type (type-of *nested-debug-condition*)))
725 (format *error-output*
726 "~&~@<(A ~S was caught when trying to print ~S when ~
727 entering the debugger. Printing was aborted and the ~
728 ~S was stored in ~S.)~@:>~%"
732 '*nested-debug-condition*))
733 (when (typep condition 'cell-error)
734 ;; what we really want to know when it's e.g. an UNBOUND-VARIABLE:
735 (format *error-output*
736 "~&(CELL-ERROR-NAME ~S) = ~S~%"
738 (cell-error-name *debug-condition*)))))
740 ;; After the initial error/condition/whatever announcement to
741 ;; *ERROR-OUTPUT*, we become interactive, and should talk on
742 ;; *DEBUG-IO* from now on. (KLUDGE: This is a normative
743 ;; statement, not a description of reality.:-| There's a lot of
744 ;; older debugger code which was written to do i/o on whatever
745 ;; stream was in fashion at the time, and not all of it has
746 ;; been converted to behave this way. -- WHN 2000-11-16)
747 (let (;; FIXME: Rebinding *STANDARD-OUTPUT* here seems wrong,
748 ;; violating the principle of least surprise, and making
749 ;; it impossible for the user to do reasonable things
750 ;; like using PRINT at the debugger prompt to send output
751 ;; to the program's ordinary (possibly
752 ;; redirected-to-a-file) *STANDARD-OUTPUT*. (CMU CL
753 ;; used to rebind *STANDARD-INPUT* here too, but that's
754 ;; been fixed already.)
755 (*standard-output* *debug-io*)
756 ;; This seems reasonable: e.g. if the user has redirected
757 ;; *ERROR-OUTPUT* to some log file, it's probably wrong
758 ;; to send errors which occur in interactive debugging to
759 ;; that file, and right to send them to *DEBUG-IO*.
760 (*error-output* *debug-io*))
761 (unless (typep condition 'step-condition)
762 (when *debug-beginner-help-p*
764 "~%~@<Within the debugger, you can type HELP for help. ~
765 At any command prompt (within the debugger or not) you ~
766 can type (SB-EXT:QUIT) to terminate the SBCL ~
767 executable. The condition which caused the debugger to ~
768 be entered is bound to ~S. You can suppress this ~
769 message by clearing ~S.~:@>~2%"
771 '*debug-beginner-help-p*))
772 (show-restarts *debug-restarts* *debug-io*))
773 (internal-debug))))))
775 (defun show-restarts (restarts s)
776 (cond ((null restarts)
778 "~&(no restarts: If you didn't do this on purpose, ~
779 please report it as a bug.)~%"))
781 (format s "~&restarts:~%")
785 (dolist (restart restarts)
786 (let ((name (restart-name restart)))
788 (let ((len (length (princ-to-string name))))
789 (when (> len max-name-len)
790 (setf max-name-len len))))))
791 (unless (zerop max-name-len)
792 (incf max-name-len 3))
793 (dolist (restart restarts)
794 (let ((name (restart-name restart)))
795 (cond ((member name names-used)
796 (format s "~& ~2D: ~V@T~A~%" count max-name-len restart))
798 (format s "~& ~2D: [~VA] ~A~%"
799 count (- max-name-len 3) name restart)
800 (push name names-used))))
803 ;;; This calls DEBUG-LOOP, performing some simple initializations
804 ;;; before doing so. INVOKE-DEBUGGER calls this to actually get into
805 ;;; the debugger. SB!KERNEL::ERROR-ERROR calls this in emergencies
806 ;;; to get into a debug prompt as quickly as possible with as little
807 ;;; risk as possible for stepping on whatever is causing recursive
809 (defun internal-debug ()
810 (let ((*in-the-debugger* t)
811 (*read-suppress* nil))
812 (unless (typep *debug-condition* 'step-condition)
813 (clear-input *debug-io*))
815 #!+mp (sb!mp:without-scheduling (debug-loop))))
819 ;;; Note: This defaulted to T in CMU CL. The changed default in SBCL
820 ;;; was motivated by desire to play nicely with ILISP.
821 (defvar *flush-debug-errors* nil
823 "When set, avoid calling INVOKE-DEBUGGER recursively when errors occur while
824 executing in the debugger.")
827 (let* ((*debug-command-level* (1+ *debug-command-level*))
828 (*real-stack-top* (sb!di:top-frame))
829 (*stack-top* (or *stack-top-hint* *real-stack-top*))
830 (*stack-top-hint* nil)
831 (*current-frame* *stack-top*))
832 (handler-bind ((sb!di:debug-condition
834 (princ condition *debug-io*)
835 (/show0 "handling d-c by THROWing DEBUG-LOOP-CATCHER")
836 (throw 'debug-loop-catcher nil))))
838 (print-frame-call *current-frame* :verbosity 2)
840 (catch 'debug-loop-catcher
841 (handler-bind ((error (lambda (condition)
842 (when *flush-debug-errors*
843 (clear-input *debug-io*)
845 ;; FIXME: Doing input on *DEBUG-IO*
846 ;; and output on T seems broken.
848 "~&error flushed (because ~
850 '*flush-debug-errors*)
851 (/show0 "throwing DEBUG-LOOP-CATCHER")
852 (throw 'debug-loop-catcher nil)))))
853 ;; We have to bind LEVEL for the restart function created by
854 ;; WITH-SIMPLE-RESTART.
855 (let ((level *debug-command-level*)
856 (restart-commands (make-restart-commands)))
857 (with-simple-restart (abort
858 "~@<Reduce debugger level (to debug level ~W).~@:>"
860 (debug-prompt *debug-io*)
861 (force-output *debug-io*)
862 (let ((input (sb!int:get-stream-command *debug-io*)))
864 (let ((cmd-fun (debug-command-p
865 (sb!int:stream-command-name input)
869 (error "unknown stream-command: ~S" input))
871 (error "ambiguous debugger command: ~S" cmd-fun))
874 (sb!int:stream-command-args input))))))
876 (let* ((exp (read *debug-io*))
877 (cmd-fun (debug-command-p exp
880 (debug-eval-print exp))
883 "~&Your command, ~S, is ambiguous:~%"
885 (dolist (ele cmd-fun)
886 (format t " ~A~%" ele)))
888 (funcall cmd-fun)))))))))))))))
890 ;;; FIXME: We could probably use INTERACTIVE-EVAL for much of this logic.
891 (defun debug-eval-print (expr)
892 (/noshow "entering DEBUG-EVAL-PRINT" expr)
893 (/noshow (fboundp 'compile))
894 (setq +++ ++ ++ + + - - expr)
895 (let* ((values (multiple-value-list (eval -)))
896 (*standard-output* *debug-io*))
897 (/noshow "done with EVAL in DEBUG-EVAL-PRINT")
899 (if values (prin1 (car values)))
900 (dolist (x (cdr values))
903 (setq /// // // / / values)
904 (setq *** ** ** * * (car values))
905 ;; Make sure that nobody passes back an unbound marker.
909 ;; FIXME: The way INTERACTIVE-EVAL does this seems better.
910 (princ "Setting * to NIL (was unbound marker)."))))
912 ;;;; debug loop functions
914 ;;; These commands are functions, not really commands, so that users
915 ;;; can get their hands on the values returned.
917 (eval-when (:execute :compile-toplevel)
919 (sb!xc:defmacro define-var-operation (ref-or-set &optional value-var)
920 `(let* ((temp (etypecase name
921 (symbol (sb!di:debug-fun-symbol-vars
922 (sb!di:frame-debug-fun *current-frame*)
924 (simple-string (sb!di:ambiguous-debug-vars
925 (sb!di:frame-debug-fun *current-frame*)
927 (location (sb!di:frame-code-location *current-frame*))
928 ;; Let's only deal with valid variables.
929 (vars (remove-if-not (lambda (v)
930 (eq (sb!di:debug-var-validity v location)
933 (declare (list vars))
935 (error "No known valid variables match ~S." name))
939 '(sb!di:debug-var-value (car vars) *current-frame*))
941 `(setf (sb!di:debug-var-value (car vars) *current-frame*)
944 ;; Since we have more than one, first see whether we have
945 ;; any variables that exactly match the specification.
946 (let* ((name (etypecase name
947 (symbol (symbol-name name))
948 (simple-string name)))
949 ;; FIXME: REMOVE-IF-NOT is deprecated, use STRING/=
951 (exact (remove-if-not (lambda (v)
952 (string= (sb!di:debug-var-symbol-name v)
955 (vars (or exact vars)))
956 (declare (simple-string name)
959 ;; Check now for only having one variable.
963 '(sb!di:debug-var-value (car vars) *current-frame*))
965 `(setf (sb!di:debug-var-value (car vars) *current-frame*)
967 ;; If there weren't any exact matches, flame about
968 ;; ambiguity unless all the variables have the same
973 (string= (sb!di:debug-var-symbol-name v)
974 (sb!di:debug-var-symbol-name (car vars))))
976 (error "specification ambiguous:~%~{ ~A~%~}"
977 (mapcar #'sb!di:debug-var-symbol-name
980 :key #'sb!di:debug-var-symbol-name))))
981 ;; All names are the same, so see whether the user
982 ;; ID'ed one of them.
984 (let ((v (find id vars :key #'sb!di:debug-var-id)))
987 "invalid variable ID, ~W: should have been one of ~S"
989 (mapcar #'sb!di:debug-var-id vars)))
992 '(sb!di:debug-var-value v *current-frame*))
994 `(setf (sb!di:debug-var-value v *current-frame*)
997 (error "Specify variable ID to disambiguate ~S. Use one of ~S."
999 (mapcar #'sb!di:debug-var-id vars)))))))))
1003 ;;; FIXME: This doesn't work. It would be real nice we could make it
1004 ;;; work! Alas, it doesn't seem to work in CMU CL X86 either..
1005 (defun var (name &optional (id 0 id-supplied))
1007 "Return a variable's value if possible. NAME is a simple-string or symbol.
1008 If it is a simple-string, it is an initial substring of the variable's name.
1009 If name is a symbol, it has the same name and package as the variable whose
1010 value this function returns. If the symbol is uninterned, then the variable
1011 has the same name as the symbol, but it has no package.
1013 If name is the initial substring of variables with different names, then
1014 this return no values after displaying the ambiguous names. If name
1015 determines multiple variables with the same name, then you must use the
1016 optional id argument to specify which one you want. If you left id
1017 unspecified, then this returns no values after displaying the distinguishing
1020 The result of this function is limited to the availability of variable
1021 information. This is SETF'able."
1022 (define-var-operation :ref))
1023 (defun (setf var) (value name &optional (id 0 id-supplied))
1024 (define-var-operation :set value))
1026 ;;; This returns the COUNT'th arg as the user sees it from args, the
1027 ;;; result of SB!DI:DEBUG-FUN-LAMBDA-LIST. If this returns a
1028 ;;; potential DEBUG-VAR from the lambda-list, then the second value is
1029 ;;; T. If this returns a keyword symbol or a value from a rest arg,
1030 ;;; then the second value is NIL.
1032 ;;; FIXME: There's probably some way to merge the code here with
1033 ;;; FRAME-ARGS-AS-LIST. (A fair amount of logic is already shared
1034 ;;; through LAMBDA-LIST-ELEMENT-DISPATCH, but I suspect more could be.)
1035 (declaim (ftype (function (index list)) nth-arg))
1036 (defun nth-arg (count args)
1038 (dolist (ele args (error "The argument specification ~S is out of range."
1040 (lambda-list-element-dispatch ele
1041 :required ((if (zerop n) (return (values ele t))))
1042 :optional ((if (zerop n) (return (values (second ele) t))))
1043 :keyword ((cond ((zerop n)
1044 (return (values (second ele) nil)))
1046 (return (values (third ele) t)))))
1047 :deleted ((if (zerop n) (return (values ele t))))
1048 :rest ((let ((var (second ele)))
1049 (lambda-var-dispatch var (sb!di:frame-code-location
1051 (error "unused &REST argument before n'th argument")
1053 (sb!di:debug-var-value var *current-frame*)
1055 "The argument specification ~S is out of range."
1058 (return-from nth-arg (values value nil))
1060 (error "invalid &REST argument before n'th argument")))))
1065 "Return the N'th argument's value if possible. Argument zero is the first
1066 argument in a frame's default printed representation. Count keyword/value
1067 pairs as separate arguments."
1068 (multiple-value-bind (var lambda-var-p)
1069 (nth-arg n (handler-case (sb!di:debug-fun-lambda-list
1070 (sb!di:frame-debug-fun *current-frame*))
1071 (sb!di:lambda-list-unavailable ()
1072 (error "No argument values are available."))))
1074 (lambda-var-dispatch var (sb!di:frame-code-location *current-frame*)
1075 (error "Unused arguments have no values.")
1076 (sb!di:debug-var-value var *current-frame*)
1077 (error "invalid argument value"))
1080 ;;;; machinery for definition of debug loop commands
1082 (defvar *debug-commands* nil)
1084 ;;; Interface to *DEBUG-COMMANDS*. No required arguments in args are
1086 (defmacro !def-debug-command (name args &rest body)
1087 (let ((fun-name (symbolicate name "-DEBUG-COMMAND")))
1089 (setf *debug-commands*
1090 (remove ,name *debug-commands* :key #'car :test #'string=))
1091 (defun ,fun-name ,args
1092 (unless *in-the-debugger*
1093 (error "invoking debugger command while outside the debugger"))
1095 (push (cons ,name #',fun-name) *debug-commands*)
1098 (defun !def-debug-command-alias (new-name existing-name)
1099 (let ((pair (assoc existing-name *debug-commands* :test #'string=)))
1100 (unless pair (error "unknown debug command name: ~S" existing-name))
1101 (push (cons new-name (cdr pair)) *debug-commands*))
1104 ;;; This takes a symbol and uses its name to find a debugger command,
1105 ;;; using initial substring matching. It returns the command function
1106 ;;; if form identifies only one command, but if form is ambiguous,
1107 ;;; this returns a list of the command names. If there are no matches,
1108 ;;; this returns nil. Whenever the loop that looks for a set of
1109 ;;; possibilities encounters an exact name match, we return that
1110 ;;; command function immediately.
1111 (defun debug-command-p (form &optional other-commands)
1112 (if (or (symbolp form) (integerp form))
1116 (format nil "~W" form)))
1119 (declare (simple-string name)
1123 ;; Find matching commands, punting if exact match.
1124 (flet ((match-command (ele)
1125 (let* ((str (car ele))
1126 (str-len (length str)))
1127 (declare (simple-string str)
1129 (cond ((< str-len len))
1131 (when (string= name str :end1 len :end2 len)
1132 (return-from debug-command-p (cdr ele))))
1133 ((string= name str :end1 len :end2 len)
1135 (mapc #'match-command *debug-commands*)
1136 (mapc #'match-command other-commands))
1138 ;; Return the right value.
1139 (cond ((not res) nil)
1142 (t ; Just return the names.
1143 (do ((cmds res (cdr cmds)))
1145 (setf (car cmds) (caar cmds))))))))
1147 ;;; Return a list of debug commands (in the same format as
1148 ;;; *DEBUG-COMMANDS*) that invoke each active restart.
1150 ;;; Two commands are made for each restart: one for the number, and
1151 ;;; one for the restart name (unless it's been shadowed by an earlier
1152 ;;; restart of the same name, or it is NIL).
1153 (defun make-restart-commands (&optional (restarts *debug-restarts*))
1155 (num 0)) ; better be the same as show-restarts!
1156 (dolist (restart restarts)
1157 (let ((name (string (restart-name restart))))
1160 (/show0 "in restart-command closure, about to i-r-i")
1161 (invoke-restart-interactively restart))))
1162 (push (cons (prin1-to-string num) restart-fun) commands)
1163 (unless (or (null (restart-name restart))
1164 (find name commands :key #'car :test #'string=))
1165 (push (cons name restart-fun) commands))))
1169 ;;;; frame-changing commands
1171 (!def-debug-command "UP" ()
1172 (let ((next (sb!di:frame-up *current-frame*)))
1174 (setf *current-frame* next)
1175 (print-frame-call next))
1177 (format t "~&Top of stack.")))))
1179 (!def-debug-command "DOWN" ()
1180 (let ((next (sb!di:frame-down *current-frame*)))
1182 (setf *current-frame* next)
1183 (print-frame-call next))
1185 (format t "~&Bottom of stack.")))))
1187 (!def-debug-command-alias "D" "DOWN")
1189 ;;; CMU CL had this command, but SBCL doesn't, since it's redundant
1190 ;;; with "FRAME 0", and it interferes with abbreviations for the
1191 ;;; TOPLEVEL restart.
1192 ;;;(!def-debug-command "TOP" ()
1193 ;;; (do ((prev *current-frame* lead)
1194 ;;; (lead (sb!di:frame-up *current-frame*) (sb!di:frame-up lead)))
1196 ;;; (setf *current-frame* prev)
1197 ;;; (print-frame-call prev))))
1199 (!def-debug-command "BOTTOM" ()
1200 (do ((prev *current-frame* lead)
1201 (lead (sb!di:frame-down *current-frame*) (sb!di:frame-down lead)))
1203 (setf *current-frame* prev)
1204 (print-frame-call prev))))
1206 (!def-debug-command-alias "B" "BOTTOM")
1208 (!def-debug-command "FRAME" (&optional
1209 (n (read-prompting-maybe "frame number: ")))
1210 (setf *current-frame*
1211 (multiple-value-bind (next-frame-fun limit-string)
1212 (if (< n (sb!di:frame-number *current-frame*))
1213 (values #'sb!di:frame-up "top")
1214 (values #'sb!di:frame-down "bottom"))
1215 (do ((frame *current-frame*))
1216 ((= n (sb!di:frame-number frame))
1218 (let ((next-frame (funcall next-frame-fun frame)))
1220 (setf frame next-frame))
1223 "The ~A of the stack was encountered.~%"
1225 (return frame)))))))
1226 (print-frame-call *current-frame*))
1228 (!def-debug-command-alias "F" "FRAME")
1230 ;;;; commands for entering and leaving the debugger
1232 ;;; CMU CL supported this QUIT debug command, but SBCL provides this
1233 ;;; functionality with a restart instead. (The QUIT debug command was
1234 ;;; removed because it's confusing to have "quit" mean two different
1235 ;;; things in the system, "restart the top level REPL" in the debugger
1236 ;;; and "terminate the Lisp system" as the SB-EXT:QUIT function.)
1238 ;;;(!def-debug-command "QUIT" ()
1239 ;;; (throw 'sb!impl::toplevel-catcher nil))
1241 ;;; CMU CL supported this GO debug command, but SBCL doesn't -- in
1242 ;;; SBCL you just type the CONTINUE restart name instead (or "C" or
1243 ;;; "RESTART CONTINUE", that's OK too).
1244 ;;;(!def-debug-command "GO" ()
1245 ;;; (continue *debug-condition*)
1246 ;;; (error "There is no restart named CONTINUE."))
1248 (!def-debug-command "RESTART" ()
1249 (/show0 "doing RESTART debug-command")
1250 (let ((num (read-if-available :prompt)))
1251 (when (eq num :prompt)
1252 (show-restarts *debug-restarts* *debug-io*)
1253 (write-string "restart: ")
1255 (setf num (read *debug-io*)))
1256 (let ((restart (typecase num
1258 (nth num *debug-restarts*))
1260 (find num *debug-restarts* :key #'restart-name
1261 :test (lambda (sym1 sym2)
1262 (string= (symbol-name sym1)
1263 (symbol-name sym2)))))
1265 (format t "~S is invalid as a restart name.~%" num)
1266 (return-from restart-debug-command nil)))))
1267 (/show0 "got RESTART")
1269 (invoke-restart-interactively restart)
1270 ;; FIXME: Even if this isn't handled by WARN, it probably
1271 ;; shouldn't go to *STANDARD-OUTPUT*, but *ERROR-OUTPUT* or
1272 ;; *QUERY-IO* or something. Look through this file to
1273 ;; straighten out stream usage.
1274 (princ "There is no such restart.")))))
1276 ;;;; information commands
1278 (!def-debug-command "HELP" ()
1279 ;; CMU CL had a little toy pager here, but "if you aren't running
1280 ;; ILISP (or a smart windowing system, or something) you deserve to
1281 ;; lose", so we've dropped it in SBCL. However, in case some
1282 ;; desperate holdout is running this on a dumb terminal somewhere,
1283 ;; we tell him where to find the message stored as a string.
1285 "~&~A~2%(The HELP string is stored in ~S.)~%"
1287 '*debug-help-string*))
1289 (!def-debug-command-alias "?" "HELP")
1291 (!def-debug-command "ERROR" ()
1292 (format *debug-io* "~A~%" *debug-condition*)
1293 (show-restarts *debug-restarts* *debug-io*))
1295 (!def-debug-command "BACKTRACE" ()
1296 (backtrace (read-if-available most-positive-fixnum)))
1298 (!def-debug-command "PRINT" ()
1299 (print-frame-call *current-frame*))
1301 (!def-debug-command-alias "P" "PRINT")
1303 (!def-debug-command "LIST-LOCALS" ()
1304 (let ((d-fun (sb!di:frame-debug-fun *current-frame*)))
1305 (if (sb!di:debug-var-info-available d-fun)
1306 (let ((*standard-output* *debug-io*)
1307 (location (sb!di:frame-code-location *current-frame*))
1308 (prefix (read-if-available nil))
1311 (dolist (v (sb!di:ambiguous-debug-vars
1313 (if prefix (string prefix) "")))
1315 (when (eq (sb!di:debug-var-validity v location) :valid)
1316 (setf any-valid-p t)
1317 (format t "~S~:[#~W~;~*~] = ~S~%"
1318 (sb!di:debug-var-symbol v)
1319 (zerop (sb!di:debug-var-id v))
1320 (sb!di:debug-var-id v)
1321 (sb!di:debug-var-value v *current-frame*))))
1325 (format t "There are no local variables ~@[starting with ~A ~]~
1329 (format t "All variables ~@[starting with ~A ~]currently ~
1330 have invalid values."
1332 (write-line "There is no variable information available."))))
1334 (!def-debug-command-alias "L" "LIST-LOCALS")
1336 (!def-debug-command "SOURCE" ()
1338 (print-code-location-source-form (sb!di:frame-code-location *current-frame*)
1339 (read-if-available 0)))
1341 ;;;; source location printing
1343 ;;; We cache a stream to the last valid file debug source so that we
1344 ;;; won't have to repeatedly open the file.
1346 ;;; KLUDGE: This sounds like a bug, not a feature. Opening files is fast
1347 ;;; in the 1990s, so the benefit is negligible, less important than the
1348 ;;; potential of extra confusion if someone changes the source during
1349 ;;; a debug session and the change doesn't show up. And removing this
1350 ;;; would simplify the system, which I like. -- WHN 19990903
1351 (defvar *cached-debug-source* nil)
1352 (declaim (type (or sb!di:debug-source null) *cached-debug-source*))
1353 (defvar *cached-source-stream* nil)
1354 (declaim (type (or stream null) *cached-source-stream*))
1356 ;;; To suppress the read-time evaluation #. macro during source read,
1357 ;;; *READTABLE* is modified. *READTABLE* is cached to avoid
1358 ;;; copying it each time, and invalidated when the
1359 ;;; *CACHED-DEBUG-SOURCE* has changed.
1360 (defvar *cached-readtable* nil)
1361 (declaim (type (or readtable null) *cached-readtable*))
1364 (setq *cached-debug-source* nil *cached-source-stream* nil
1365 *cached-readtable* nil))
1366 *before-save-initializations*)
1368 ;;; We also cache the last toplevel form that we printed a source for
1369 ;;; so that we don't have to do repeated reads and calls to
1370 ;;; FORM-NUMBER-TRANSLATIONS.
1371 (defvar *cached-toplevel-form-offset* nil)
1372 (declaim (type (or index null) *cached-toplevel-form-offset*))
1373 (defvar *cached-toplevel-form*)
1374 (defvar *cached-form-number-translations*)
1376 ;;; Given a code location, return the associated form-number
1377 ;;; translations and the actual top level form. We check our cache ---
1378 ;;; if there is a miss, we dispatch on the kind of the debug source.
1379 (defun get-toplevel-form (location)
1380 (let ((d-source (sb!di:code-location-debug-source location)))
1381 (if (and (eq d-source *cached-debug-source*)
1382 (eql (sb!di:code-location-toplevel-form-offset location)
1383 *cached-toplevel-form-offset*))
1384 (values *cached-form-number-translations* *cached-toplevel-form*)
1385 (let* ((offset (sb!di:code-location-toplevel-form-offset location))
1387 (ecase (sb!di:debug-source-from d-source)
1388 (:file (get-file-toplevel-form location))
1389 (:lisp (svref (sb!di:debug-source-name d-source) offset)))))
1390 (setq *cached-toplevel-form-offset* offset)
1391 (values (setq *cached-form-number-translations*
1392 (sb!di:form-number-translations res offset))
1393 (setq *cached-toplevel-form* res))))))
1395 ;;; Locate the source file (if it still exists) and grab the top level
1396 ;;; form. If the file is modified, we use the top level form offset
1397 ;;; instead of the recorded character offset.
1398 (defun get-file-toplevel-form (location)
1399 (let* ((d-source (sb!di:code-location-debug-source location))
1400 (tlf-offset (sb!di:code-location-toplevel-form-offset location))
1401 (local-tlf-offset (- tlf-offset
1402 (sb!di:debug-source-root-number d-source)))
1404 (aref (or (sb!di:debug-source-start-positions d-source)
1405 (error "no start positions map"))
1407 (name (sb!di:debug-source-name d-source)))
1408 (unless (eq d-source *cached-debug-source*)
1409 (unless (and *cached-source-stream*
1410 (equal (pathname *cached-source-stream*)
1412 (setq *cached-readtable* nil)
1413 (when *cached-source-stream* (close *cached-source-stream*))
1414 (setq *cached-source-stream* (open name :if-does-not-exist nil))
1415 (unless *cached-source-stream*
1416 (error "The source file no longer exists:~% ~A" (namestring name)))
1417 (format t "~%; file: ~A~%" (namestring name)))
1419 (setq *cached-debug-source*
1420 (if (= (sb!di:debug-source-created d-source)
1421 (file-write-date name))
1425 ((eq *cached-debug-source* d-source)
1426 (file-position *cached-source-stream* char-offset))
1428 (format t "~%; File has been modified since compilation:~%; ~A~@
1429 ; Using form offset instead of character position.~%"
1431 (file-position *cached-source-stream* 0)
1432 (let ((*read-suppress* t))
1433 (dotimes (i local-tlf-offset)
1434 (read *cached-source-stream*)))))
1435 (unless *cached-readtable*
1436 (setq *cached-readtable* (copy-readtable))
1437 (set-dispatch-macro-character
1439 (lambda (stream sub-char &rest rest)
1440 (declare (ignore rest sub-char))
1441 (let ((token (read stream t nil t)))
1442 (format nil "#.~S" token)))
1443 *cached-readtable*))
1444 (let ((*readtable* *cached-readtable*))
1445 (read *cached-source-stream*))))
1447 (defun print-code-location-source-form (location context)
1448 (let* ((location (maybe-block-start-location location))
1449 (form-num (sb!di:code-location-form-number location)))
1450 (multiple-value-bind (translations form) (get-toplevel-form location)
1451 (unless (< form-num (length translations))
1452 (error "The source path no longer exists."))
1453 (prin1 (sb!di:source-path-context form
1454 (svref translations form-num)
1457 ;;; breakpoint and step commands
1459 ;;; Step to the next code-location.
1460 (!def-debug-command "STEP" ()
1461 (setf *number-of-steps* (read-if-available 1))
1462 (set-step-breakpoint *current-frame*)
1463 (continue *debug-condition*)
1464 (error "couldn't continue"))
1466 ;;; List possible breakpoint locations, which ones are active, and
1467 ;;; where the CONTINUE restart will transfer control. Set
1468 ;;; *POSSIBLE-BREAKPOINTS* to the code-locations which can then be
1469 ;;; used by sbreakpoint.
1470 (!def-debug-command "LIST-LOCATIONS" ()
1471 (let ((df (read-if-available *default-breakpoint-debug-fun*)))
1473 (setf df (sb!di:fun-debug-fun (eval df)))
1474 (setf *default-breakpoint-debug-fun* df))
1476 (not *default-breakpoint-debug-fun*))
1477 (setf df (sb!di:frame-debug-fun *current-frame*))
1478 (setf *default-breakpoint-debug-fun* df)))
1479 (setf *possible-breakpoints* (possible-breakpoints df)))
1480 (let ((continue-at (sb!di:frame-code-location *current-frame*)))
1481 (let ((active (location-in-list *default-breakpoint-debug-fun*
1482 *breakpoints* :fun-start))
1483 (here (sb!di:code-location=
1484 (sb!di:debug-fun-start-location
1485 *default-breakpoint-debug-fun*) continue-at)))
1486 (when (or active here)
1487 (format t "::FUN-START ")
1488 (when active (format t " *Active*"))
1489 (when here (format t " *Continue here*"))))
1491 (let ((prev-location nil)
1496 (let ((this-num (1- this-num)))
1497 (if (= prev-num this-num)
1498 (format t "~&~W: " prev-num)
1499 (format t "~&~W-~W: " prev-num this-num)))
1500 (print-code-location-source-form prev-location 0)
1501 (when *print-location-kind*
1502 (format t "~S " (sb!di:code-location-kind prev-location)))
1503 (when (location-in-list prev-location *breakpoints*)
1504 (format t " *Active*"))
1505 (when (sb!di:code-location= prev-location continue-at)
1506 (format t " *Continue here*")))))
1508 (dolist (code-location *possible-breakpoints*)
1509 (when (or *print-location-kind*
1510 (location-in-list code-location *breakpoints*)
1511 (sb!di:code-location= code-location continue-at)
1513 (not (eq (sb!di:code-location-debug-source code-location)
1514 (sb!di:code-location-debug-source prev-location)))
1515 (not (eq (sb!di:code-location-toplevel-form-offset
1517 (sb!di:code-location-toplevel-form-offset
1519 (not (eq (sb!di:code-location-form-number code-location)
1520 (sb!di:code-location-form-number prev-location))))
1522 (setq prev-location code-location prev-num this-num))
1526 (when (location-in-list *default-breakpoint-debug-fun*
1529 (format t "~&::FUN-END *Active* "))))
1531 (!def-debug-command-alias "LL" "LIST-LOCATIONS")
1533 ;;; Set breakpoint at the given number.
1534 (!def-debug-command "BREAKPOINT" ()
1535 (let ((index (read-prompting-maybe "location number, :START, or :END: "))
1539 (print-functions nil)
1542 (place *default-breakpoint-debug-fun*))
1543 (flet ((get-command-line ()
1544 (let ((command-line nil)
1547 (let ((next-input (read-if-available unique)))
1548 (when (eq next-input unique) (return))
1549 (push next-input command-line)))
1550 (nreverse command-line)))
1551 (set-vars-from-command-line (command-line)
1552 (do ((arg (pop command-line) (pop command-line)))
1555 (:condition (setf condition (pop command-line)))
1556 (:print (push (pop command-line) print))
1557 (:break (setf break (pop command-line)))
1559 (setf function (eval (pop command-line)))
1560 (setf *default-breakpoint-debug-fun*
1561 (sb!di:fun-debug-fun function))
1562 (setf place *default-breakpoint-debug-fun*)
1563 (setf *possible-breakpoints*
1564 (possible-breakpoints
1565 *default-breakpoint-debug-fun*))))))
1567 (let ((code-loc (sb!di:debug-fun-start-location place)))
1568 (setf bp (sb!di:make-breakpoint #'main-hook-fun
1571 (setf break (sb!di:preprocess-for-eval break code-loc))
1572 (setf condition (sb!di:preprocess-for-eval condition code-loc))
1573 (dolist (form print)
1574 (push (cons (sb!di:preprocess-for-eval form code-loc) form)
1578 (sb!di:make-breakpoint #'main-hook-fun
1582 ;; FIXME: These and any other old (COERCE `(LAMBDA ..) ..)
1583 ;; forms should be converted to shiny new (LAMBDA ..) forms.
1584 ;; (Search the sources for "coerce.*\(lambda".)
1585 (coerce `(lambda (dummy)
1586 (declare (ignore dummy)) ,break)
1588 (setf condition (coerce `(lambda (dummy)
1589 (declare (ignore dummy)) ,condition)
1591 (dolist (form print)
1593 (coerce `(lambda (dummy)
1594 (declare (ignore dummy)) ,form) 'function)
1597 (setup-code-location ()
1598 (setf place (nth index *possible-breakpoints*))
1599 (setf bp (sb!di:make-breakpoint #'main-hook-fun place
1600 :kind :code-location))
1601 (dolist (form print)
1603 (sb!di:preprocess-for-eval form place)
1606 (setf break (sb!di:preprocess-for-eval break place))
1607 (setf condition (sb!di:preprocess-for-eval condition place))))
1608 (set-vars-from-command-line (get-command-line))
1610 ((or (eq index :start) (eq index :s))
1612 ((or (eq index :end) (eq index :e))
1615 (setup-code-location)))
1616 (sb!di:activate-breakpoint bp)
1617 (let* ((new-bp-info (create-breakpoint-info place bp index
1619 :print print-functions
1620 :condition condition))
1621 (old-bp-info (location-in-list new-bp-info *breakpoints*)))
1623 (sb!di:deactivate-breakpoint (breakpoint-info-breakpoint
1625 (setf *breakpoints* (remove old-bp-info *breakpoints*))
1626 (format t "previous breakpoint removed~%"))
1627 (push new-bp-info *breakpoints*))
1628 (print-breakpoint-info (first *breakpoints*))
1629 (format t "~&added"))))
1631 (!def-debug-command-alias "BP" "BREAKPOINT")
1633 ;;; List all breakpoints which are set.
1634 (!def-debug-command "LIST-BREAKPOINTS" ()
1636 (sort *breakpoints* #'< :key #'breakpoint-info-breakpoint-number))
1637 (dolist (info *breakpoints*)
1638 (print-breakpoint-info info)))
1640 (!def-debug-command-alias "LB" "LIST-BREAKPOINTS")
1641 (!def-debug-command-alias "LBP" "LIST-BREAKPOINTS")
1643 ;;; Remove breakpoint N, or remove all breakpoints if no N given.
1644 (!def-debug-command "DELETE-BREAKPOINT" ()
1645 (let* ((index (read-if-available nil))
1647 (find index *breakpoints* :key #'breakpoint-info-breakpoint-number)))
1649 (sb!di:delete-breakpoint (breakpoint-info-breakpoint bp-info))
1650 (setf *breakpoints* (remove bp-info *breakpoints*))
1651 (format t "breakpoint ~S removed~%" index))
1652 (index (format t "The breakpoint doesn't exist."))
1654 (dolist (ele *breakpoints*)
1655 (sb!di:delete-breakpoint (breakpoint-info-breakpoint ele)))
1656 (setf *breakpoints* nil)
1657 (format t "all breakpoints deleted~%")))))
1659 (!def-debug-command-alias "DBP" "DELETE-BREAKPOINT")
1661 ;;; miscellaneous commands
1663 (!def-debug-command "DESCRIBE" ()
1664 (let* ((curloc (sb!di:frame-code-location *current-frame*))
1665 (debug-fun (sb!di:code-location-debug-fun curloc))
1666 (function (sb!di:debug-fun-fun debug-fun)))
1669 (format t "can't figure out the function for this frame"))))
1671 (!def-debug-command "SLURP" ()
1672 (loop while (read-char-no-hang *standard-input*)))
1674 ;;;; debug loop command utilities
1676 (defun read-prompting-maybe (prompt)
1677 (unless (sb!int:listen-skip-whitespace *debug-io*)
1682 (defun read-if-available (default)
1683 (if (sb!int:listen-skip-whitespace *debug-io*)