\f
;;;; BACKTRACE
-(defun map-backtrace (thunk &key (start 0) (count most-positive-fixnum))
- (loop
- with result = nil
- for index upfrom 0
- for frame = (if *in-the-debugger*
- *current-frame*
- (sb!di:top-frame))
- then (sb!di:frame-down frame)
- until (null frame)
- when (<= start index) do
- (if (minusp (decf count))
- (return result)
- (setf result (funcall thunk frame)))
- finally (return result)))
-
-(defun backtrace (&optional (count most-positive-fixnum) (stream *debug-io*))
+(declaim (unsigned-byte *backtrace-frame-count*))
+(defvar *backtrace-frame-count* 1000
+ "Default number of frames to backtrace. Defaults to 1000.")
+
+(declaim (type (member :minimal :normal :full) *method-frame-style*))
+(defvar *method-frame-style* :normal
+ "Determines how frames corresponding to method functions are represented in
+backtraces. Possible values are :MINIMAL, :NORMAL, and :FULL.
+
+ :MINIMAL represents them as
+
+ (<gf-name> ...args...)
+
+ if all arguments are available, and only a single method is applicable to
+ the arguments -- otherwise behaves as :NORMAL.
+
+ :NORMAL represents them as
+
+ ((:method <gf-name> [<qualifier>*] (<specializer>*)) ...args...)
+
+ The frame is then followed by either [fast-method] or [slow-method],
+ designating the kind of method function. (See below.)
+
+ :FULL represents them using the actual funcallable method function name:
+
+ ((sb-pcl:fast-method <gf-name> [<qualifier>*] (<specializer>*)) ...args...)
+
+ or
+
+ ((sb-pcl:slow-method <gf-name> [<qualifier>*] (<specializer>*)) ...args...)
+
+ In the this case arguments may include values internal to SBCL's method
+ dispatch machinery.")
+
+(define-deprecated-variable :early "1.1.4.9" *show-entry-point-details*
+ :value nil)
+
+(defun backtrace (&optional (count *backtrace-frame-count*) (stream *debug-io*))
+ "Replaced by PRINT-BACKTRACE, will eventually be deprecated."
+ (print-backtrace :count count :stream stream))
+
+(defun backtrace-as-list (&optional (count *backtrace-frame-count*))
+ "Replaced by LIST-BACKTRACE, will eventually be deprecated."
+ (list-backtrace :count count))
+
+(defun backtrace-start-frame (frame-designator)
+ (let ((here (sb!di:top-frame)))
+ (labels ((current-frame ()
+ (let ((frame here))
+ ;; Our caller's caller.
+ (loop repeat 2
+ do (setf frame (or (sb!di:frame-down frame) frame)))
+ frame))
+ (interrupted-frame ()
+ (or (nth-value 1 (find-interrupted-name-and-frame))
+ (current-frame))))
+ (cond ((eq :current-frame frame-designator)
+ (current-frame))
+ ((eq :interrupted-frame frame-designator)
+ (interrupted-frame))
+ ((eq :debugger-frame frame-designator)
+ (if (and *in-the-debugger* *current-frame*)
+ *current-frame*
+ (interrupted-frame)))
+ ((sb!di:frame-p frame-designator)
+ frame-designator)
+ (t
+ (error "Invalid designator for initial backtrace frame: ~S"
+ frame-designator))))))
+
+(defun map-backtrace (function &key
+ (start 0)
+ (from :debugger-frame)
+ (count *backtrace-frame-count*))
#!+sb-doc
- "Show a listing of the call stack going down from the current frame.
-In the debugger, the current frame is indicated by the prompt. COUNT
-is how many frames to show."
+ "Calls the designated FUNCTION with each frame on the call stack.
+Returns the last value returned by FUNCTION.
+
+COUNT is the number of frames to backtrace, defaulting to
+*BACKTRACE-FRAME-COUNT*.
+
+START is the number of the frame the backtrace should start from.
+
+FROM specifies the frame relative to which the frames are numbered. Possible
+values are an explicit SB-DI:FRAME object, and the
+keywords :CURRENT-FRAME, :INTERRUPTED-FRAME, and :DEBUGGER-FRAME. Default
+is :DEBUGGER-FRAME.
+
+ :CURRENT-FRAME
+ specifies the caller of MAP-BACKTRACE.
+
+ :INTERRUPTED-FRAME
+ specifies the first interrupted frame on the stack \(typically the frame
+ where the error occured, as opposed to error handling frames) if any,
+ otherwise behaving as :CURRENT-FRAME.
+
+ :DEBUGGER-FRAME
+ specifies the currently debugged frame when inside the debugger, and
+ behaves as :INTERRUPTED-FRAME outside the debugger.
+"
+ (loop with result = nil
+ for index upfrom 0
+ for frame = (backtrace-start-frame from)
+ then (sb!di:frame-down frame)
+ until (null frame)
+ when (<= start index) do
+ (if (minusp (decf count))
+ (return result)
+ (setf result (funcall function frame)))
+ finally (return result)))
+
+(defun print-backtrace (&key
+ (stream *debug-io*)
+ (start 0)
+ (from :debugger-frame)
+ (count *backtrace-frame-count*)
+ (print-thread t)
+ (print-frame-source nil)
+ (method-frame-style *method-frame-style*))
+ #!+sb-doc
+ "Print a listing of the call stack to STREAM, defaulting to *DEBUG-IO*.
+
+COUNT is the number of frames to backtrace, defaulting to
+*BACKTRACE-FRAME-COUNT*.
+
+START is the number of the frame the backtrace should start from.
+
+FROM specifies the frame relative to which the frames are numbered. Possible
+values are an explicit SB-DI:FRAME object, and the
+keywords :CURRENT-FRAME, :INTERRUPTED-FRAME, and :DEBUGGER-FRAME. Default
+is :DEBUGGER-FRAME.
+
+ :CURRENT-FRAME
+ specifies the caller of PRINT-BACKTRACE.
+
+ :INTERRUPTED-FRAME
+ specifies the first interrupted frame on the stack \(typically the frame
+ where the error occured, as opposed to error handling frames) if any,
+ otherwise behaving as :CURRENT-FRAME.
+
+ :DEBUGGER-FRAME
+ specifies the currently debugged frame when inside the debugger, and
+ behaves as :INTERRUPTED-FRAME outside the debugger.
+
+If PRINT-THREAD is true (default), backtrace is preceded by printing the
+thread object the backtrace is from.
+
+If PRINT-FRAME-SOURCE is true (default is false), each frame is followed by
+printing the currently executing source form in the function responsible for
+that frame, when available. Requires the function to have been compiled at
+DEBUG 2 or higher. If PRINT-FRAME-SOURCE is :ALWAYS, it also reports \"no
+source available\" for frames for which were compiled at lower debug settings.
+
+METHOD-FRAME-STYLE (defaulting to *METHOD-FRAME-STYLE*), determines how frames
+corresponding to method functions are printed. Possible values
+are :MINIMAL, :NORMAL, and :FULL. See *METHOD-FRAME-STYLE* for more
+information."
(fresh-line stream)
+ (when print-thread
+ (format stream "Backtrace for: ~S~%" sb!thread:*current-thread*))
(let ((*suppress-print-errors* (if (subtypep 'serious-condition *suppress-print-errors*)
*suppress-print-errors*
'serious-condition))
- (*print-circle* t))
+ (*print-circle* t)
+ (n start))
(handler-bind ((print-not-readable #'print-unreadably))
(map-backtrace (lambda (frame)
- (print-frame-call frame stream :number t))
+ (print-frame-call frame stream
+ :number n
+ :method-frame-style method-frame-style
+ :print-frame-source print-frame-source)
+ (incf n))
+ :from (backtrace-start-frame from)
+ :start start
:count count)))
(fresh-line stream)
(values))
-(defun backtrace-as-list (&optional (count most-positive-fixnum))
+(defun list-backtrace (&key
+ (count *backtrace-frame-count*)
+ (start 0)
+ (from :debugger-frame)
+ (method-frame-style *method-frame-style*))
#!+sb-doc
- "Return a list representing the current BACKTRACE.
-
-Objects in the backtrace with dynamic-extent allocation by the current
-thread are represented by substitutes to avoid references to them from
-leaking outside their legal extent."
- (let ((reversed-result (list)))
- (map-backtrace (lambda (frame)
- (let ((frame-list (frame-call-as-list frame)))
- (if (listp (cdr frame-list))
- (push (mapcar #'replace-dynamic-extent-object frame-list)
- reversed-result)
- (push frame-list reversed-result))))
- :count count)
- (nreverse reversed-result)))
-
-(defun frame-call-as-list (frame)
- (multiple-value-bind (name args) (frame-call frame)
- (cons name args)))
+ "Returns a list describing the call stack. Each frame is represented
+by a sublist:
+
+ \(<name> ...args...)
+
+where the name describes the function responsible for the frame. The name
+might not be bound to the actual function object. Unavailable arguments are
+represented by dummy objects that print as #<unavailable argument>. Objects
+with dynamic-extent allocation by the current thread are represented by
+substitutes to avoid references to them from leaking outside their legal
+extent.
+
+COUNT is the number of frames to backtrace, defaulting to
+*BACKTRACE-FRAME-COUNT*.
+
+START is the number of the frame the backtrace should start from.
+
+FROM specifies the frame relative to which the frames are numbered. Possible
+values are an explicit SB-DI:FRAME object, and the
+keywords :CURRENT-FRAME, :INTERRUPTED-FRAME, and :DEBUGGER-FRAME. Default
+is :DEBUGGER-FRAME.
+
+ :CURRENT-FRAME
+ specifies the caller of LIST-BACKTRACE.
+
+ :INTERRUPTED-FRAME
+ specifies the first interrupted frame on the stack \(typically the frame
+ where the error occured, as opposed to error handling frames) if any,
+ otherwise behaving as :CURRENT-FRAME.
+
+ :DEBUGGER-FRAME
+ specifies the currently debugged frame when inside the debugger, and
+ behaves as :INTERRUPTED-FRAME outside the debugger.
+
+METHOD-FRAME-STYLE (defaulting to *METHOD-FRAME-STYLE*), determines how frames
+corresponding to method functions are printed. Possible values
+are :MINIMAL, :NORMAL, and :FULL. See *METHOD-FRAME-STYLE* for more
+information."
+ (let (rbacktrace)
+ (map-backtrace
+ (lambda (frame)
+ (push (frame-call-as-list frame :method-frame-style method-frame-style)
+ rbacktrace))
+ :count count
+ :start start
+ :from (backtrace-start-frame from))
+ (nreverse rbacktrace)))
+
+(defun frame-call-as-list (frame &key (method-frame-style *method-frame-style*))
+ (multiple-value-bind (name args info)
+ (frame-call frame :method-frame-style method-frame-style
+ :replace-dynamic-extent-objects t)
+ (values (cons name args) info)))
(defun replace-dynamic-extent-object (obj)
(if (stack-allocated-p obj)
(sb!di:lambda-list-unavailable ()
(make-unprintable-object "unavailable lambda list"))))
-(defvar *show-entry-point-details* nil)
-
-(defun clean-xep (name args)
+(defun clean-xep (name args info)
(values (second name)
(if (consp args)
(let* ((count (first args))
(make-unprintable-object "unknown"))
collect arg)
real-args))
- args)))
+ args)
+ (if (eq (car name) 'sb!c::tl-xep)
+ (cons :tl info)
+ info)))
-(defun clean-&more-processor (name args)
+(defun clean-&more-processor (name args info)
(values (second name)
(if (consp args)
(let* ((more (last args 2))
(sb!c:%more-arg-values context 0 count))
(list
(make-unprintable-object "more unavailable arguments")))))
- args)))
+ args)
+ (cons :more info)))
+
+(defun clean-fast-method (name args style info)
+ (multiple-value-bind (cname cargs)
+ (ecase style
+ (:minimal
+ (let ((gf-name (second name))
+ (real-args (cddr args)))
+ (if (and (fboundp gf-name)
+ (notany #'sb!impl::unprintable-object-p real-args)
+ (let ((methods (compute-applicable-methods
+ (fdefinition gf-name) real-args)))
+ (and methods (not (cdr methods)))))
+ (values gf-name real-args)
+ (values (cons :method (cdr name)) real-args))))
+ (:normal
+ (values (cons :method (cdr name)) (cddr args)))
+ (:full
+ (values name args)))
+ (values cname cargs (cons :fast-method info))))
-(defun clean-debug-fun-name (name &optional args)
- ;; FIXME: do we need to deal with
- ;; HAIRY-FUNCTION-ENTRY here? I can't make it or
- ;; &AUX-BINDINGS appear in backtraces, so they are
- ;; left alone for now. --NS 2005-02-28
+(defun clean-frame-call (name args method-frame-style info)
(if (consp name)
(case (first name)
((sb!c::xep sb!c::tl-xep)
- (clean-xep name args))
+ (clean-xep name args info))
((sb!c::&more-processor)
- (clean-&more-processor name args))
- ((sb!c::hairy-arg-processor
- sb!c::varargs-entry sb!c::&optional-processor)
- (clean-debug-fun-name (second name) args))
+ (clean-&more-processor name args info))
+ ((sb!c::&optional-processor)
+ (clean-frame-call (second name) args method-frame-style
+ info))
+ ((sb!pcl::fast-method)
+ (clean-fast-method name args method-frame-style info))
(t
- (values name args)))
- (values name args)))
-
-(defun frame-call (frame)
- (labels ((clean-name-and-args (name args)
- (if (not *show-entry-point-details*)
- (clean-debug-fun-name name args)
- (values name args))))
- (let ((debug-fun (sb!di:frame-debug-fun frame)))
- (multiple-value-bind (name args)
- (clean-name-and-args (sb!di:debug-fun-name debug-fun)
- (frame-args-as-list frame))
- (values name args (sb!di:debug-fun-kind debug-fun))))))
+ (values name args info)))
+ (values name args info)))
+
+(defun frame-call (frame &key (method-frame-style *method-frame-style*)
+ replace-dynamic-extent-objects)
+ "Returns as multiple values a descriptive name for the function responsible
+for FRAME, arguments that that function, and a list providing additional
+information about the frame.
+
+Unavailable arguments are represented using dummy-objects printing as
+#<unavailable argument>.
+
+METHOD-FRAME-STYLE (defaulting to *METHOD-FRAME-STYLE*), determines how frames
+corresponding to method functions are printed. Possible values
+are :MINIMAL, :NORMAL, and :FULL. See *METHOD-FRAME-STYLE* for more
+information.
+
+If REPLACE-DYNAMIC-EXTENT-OBJECTS is true, objects allocated on the stack of
+the current thread are replaced with dummy objects which can safely escape."
+ (let* ((debug-fun (sb!di:frame-debug-fun frame))
+ (kind (sb!di:debug-fun-kind debug-fun)))
+ (multiple-value-bind (name args info)
+ (clean-frame-call (sb!di:debug-fun-name debug-fun)
+ (frame-args-as-list frame)
+ method-frame-style
+ (when kind (list kind)))
+ (let ((args (if (and (consp args) replace-dynamic-extent-objects)
+ (mapcar #'replace-dynamic-extent-object args)
+ args)))
+ (values name args info)))))
(defun ensure-printable-object (object)
(handler-case
;;; zero indicates just printing the DEBUG-FUN's name, and one
;;; indicates displaying call-like, one-liner format with argument
;;; values.
-(defun print-frame-call (frame stream &key (verbosity 1) (number nil))
+(defun print-frame-call (frame stream
+ &key print-frame-source
+ number
+ (method-frame-style *method-frame-style*))
(when number
- (format stream "~&~S: " (sb!di:frame-number frame)))
- (if (zerop verbosity)
- (let ((*print-readably* nil))
- (prin1 frame stream))
- (multiple-value-bind (name args kind) (frame-call frame)
- (pprint-logical-block (stream nil :prefix "(" :suffix ")")
- ;; Since we go to some trouble to make nice informative function
- ;; names like (PRINT-OBJECT :AROUND (CLOWN T)), let's make sure
- ;; that they aren't truncated by *PRINT-LENGTH* and *PRINT-LEVEL*.
- ;; For the function arguments, we can just print normally.
- (let ((*print-length* nil)
- (*print-level* nil))
- (prin1 name stream))
- ;; If we hit a &REST arg, then print as many of the values
- ;; as possible, punting the loop over lambda-list variables
- ;; since any other arguments will be in the &REST arg's list
- ;; of values. Special case *PRINT-PRETTY* for eval frames:
- ;; if *PRINT-LINES* is 1, turn off pretty-printing.
- (let ((*print-pretty*
- (if (and (eql 1 *print-lines*)
- (member name '(eval simple-eval-in-lexenv)))
- nil
- *print-pretty*))))
+ (format stream "~&~S: " (if (integerp number)
+ number
+ (sb!di:frame-number frame))))
+ (multiple-value-bind (name args info)
+ (frame-call frame :method-frame-style method-frame-style)
+ (pprint-logical-block (stream nil :prefix "(" :suffix ")")
+ ;; Since we go to some trouble to make nice informative function
+ ;; names like (PRINT-OBJECT :AROUND (CLOWN T)), let's make sure
+ ;; that they aren't truncated by *PRINT-LENGTH* and *PRINT-LEVEL*.
+ ;; For the function arguments, we can just print normally.
+ (let ((*print-length* nil)
+ (*print-level* nil)
+ (*print-pretty* nil)
+ (*print-circle* t)
+ (name (ensure-printable-object name)))
+ (write name :stream stream :escape t :pretty (equal '(lambda ()) name))
+ ;; If we hit a &REST arg, then print as many of the values as
+ ;; possible, punting the loop over lambda-list variables since any
+ ;; other arguments will be in the &REST arg's list of values.
+ (let ((args (ensure-printable-object args)))
(if (listp args)
(format stream "~{ ~_~S~}" args)
- (format stream " ~S" args)))
- (when kind
- (format stream "[~S]" kind))))
- (when (>= verbosity 2)
+ (format stream " ~S" args)))))
+ (when info
+ (format stream " [~{~(~A~)~^,~}]" info)))
+ (when print-frame-source
(let ((loc (sb!di:frame-code-location frame)))
(handler-case
- (progn
- ;; FIXME: Is this call really necessary here? If it is,
- ;; then the reason for it should be unobscured.
- (sb!di:code-location-debug-block loc)
- (format stream "~%source: ")
- (prin1 (code-location-source-form loc 0) stream))
- (sb!di:debug-condition (ignore)
- ignore)
+ (let ((source (handler-case
+ (code-location-source-form loc 0)
+ (error (c)
+ (format stream "~& error finding frame source: ~A" c)))))
+ (format stream "~% source: ~S" source))
+ (sb!di:debug-condition ()
+ ;; This is mostly noise.
+ (when (eq :always print-frame-source)
+ (format stream "~& no source available for frame")))
(error (c)
- (format stream "~&error finding source: ~A" c))))))
+ (format stream "~& error printing frame source: ~A" c))))))
\f
;;;; INVOKE-DEBUGGER
(when *debug-beginner-help-p*
(format *debug-io*
"~%~@<Type HELP for debugger help, or ~
- (SB-EXT:QUIT) to exit from SBCL.~:@>~2%"))
+ (SB-EXT:EXIT) to exit from SBCL.~:@>~2%"))
(show-restarts *debug-restarts* *debug-io*))
(internal-debug))
(when background-p
(finish-output *error-output*)
;; (Where to truncate the BACKTRACE is of course arbitrary, but
;; it seems as though we should at least truncate it somewhere.)
- (sb!debug:backtrace 128 *error-output*)
+ (print-backtrace :count 128 :stream *error-output*
+ :from :interrupted-frame)
(format
*error-output*
"~%unhandled condition in --disable-debugger mode, quitting~%")
"When set, avoid calling INVOKE-DEBUGGER recursively when errors occur while
executing in the debugger.")
-(defun debug-read (stream)
+(defun debug-read (stream eof-restart)
(declare (type stream stream))
(let* ((eof-marker (cons nil nil))
(form (read stream nil eof-marker)))
(if (eq form eof-marker)
- (abort)
+ (invoke-restart eof-restart)
form)))
(defun debug-loop-fun ()
(setf *suppress-frame-print* nil))
(t
(terpri *debug-io*)
- (print-frame-call *current-frame* *debug-io* :verbosity 2)))
+ (print-frame-call *current-frame* *debug-io* :print-frame-source t)))
(loop
(catch 'debug-loop-catcher
(handler-bind ((error (lambda (condition)
'*flush-debug-errors*)
(/show0 "throwing DEBUG-LOOP-CATCHER")
(throw 'debug-loop-catcher nil)))))
- ;; We have to bind LEVEL for the restart function created by
- ;; WITH-SIMPLE-RESTART.
+ ;; We have to bind LEVEL for the restart function created
+ ;; by WITH-SIMPLE-RESTART, and we need the explicit ABORT
+ ;; restart that exists now so that EOF from read can drop
+ ;; one debugger level.
(let ((level *debug-command-level*)
- (restart-commands (make-restart-commands)))
+ (restart-commands (make-restart-commands))
+ (abort-restart-for-eof (find-restart 'abort)))
(flush-standard-output-streams)
(debug-prompt *debug-io*)
(force-output *debug-io*)
- (let* ((exp (debug-read *debug-io*))
- (cmd-fun (debug-command-p exp restart-commands)))
- (with-simple-restart (abort
- "~@<Reduce debugger level (to debug level ~W).~@:>"
- level)
+ (with-simple-restart (abort
+ "~@<Reduce debugger level (to debug level ~W).~@:>"
+ level)
+ (let* ((exp (debug-read *debug-io* abort-restart-for-eof))
+ (cmd-fun (debug-command-p exp restart-commands)))
(cond ((not cmd-fun)
(debug-eval-print exp))
((consp cmd-fun)
(show-restarts *debug-restarts* *debug-io*))
(!def-debug-command "BACKTRACE" ()
- (backtrace (read-if-available most-positive-fixnum)))
+ (print-backtrace :count (read-if-available most-positive-fixnum)))
(!def-debug-command "PRINT" ()
(print-frame-call *current-frame* *debug-io*))