;;;; files for more information.
(in-package "SB!IMPL")
-
-(file-comment
- "$Header$")
-\f
-(defconstant most-positive-fixnum #.sb!vm:*target-most-positive-fixnum*
- #!+sb-doc
- "The fixnum closest in value to positive infinity.")
-
-(defconstant most-negative-fixnum #.sb!vm:*target-most-negative-fixnum*
- #!+sb-doc
- "The fixnum closest in value to negative infinity.")
\f
-;;;; magic specials initialized by genesis
+;;;; magic specials initialized by GENESIS
-#!-gengc
+;;; FIXME: The DEFVAR here is redundant with the (DECLAIM (SPECIAL ..))
+;;; of all static symbols in early-impl.lisp.
(progn
(defvar *current-catch-block*)
(defvar *current-unwind-protect-block*)
\f
;;; specials initialized by !COLD-INIT
-;;; FIXME: These could be converted to DEFVARs, and the stuff shared
-;;; in both #!+GENGC and #!-GENGC (actually everything in #!+GENGC)
-;;; could be made non-conditional.
-(declaim
- #!-gengc
- (special *gc-inhibit* *already-maybe-gcing*
- *need-to-collect-garbage* *gc-verbose*
- *gc-notify-stream*
- *before-gc-hooks* *after-gc-hooks*
- #!+x86 *pseudo-atomic-atomic*
- #!+x86 *pseudo-atomic-interrupted*
- sb!unix::*interrupts-enabled*
- sb!unix::*interrupt-pending*
- *type-system-initialized*)
- #!+gengc
- (special *gc-verbose* *before-gc-hooks* *after-gc-hooks*
- *gc-notify-stream*
- *type-system-initialized*))
+;;; FIXME: These could be converted to DEFVARs.
+(declaim (special *gc-inhibit* *already-maybe-gcing*
+ *need-to-collect-garbage*
+ *gc-notify-stream*
+ *before-gc-hooks* *after-gc-hooks*
+ #!+x86 *pseudo-atomic-atomic*
+ #!+x86 *pseudo-atomic-interrupted*
+ sb!unix::*interrupts-enabled*
+ sb!unix::*interrupt-pending*
+ *type-system-initialized*))
(defvar *cold-init-complete-p*)
\f
;;;; working with *CURRENT-ERROR-DEPTH* and *MAXIMUM-ERROR-DEPTH*
-;;; INFINITE-ERROR-PROTECT is used by ERROR and friends to keep us out of
-;;; hyperspace.
+;;; INFINITE-ERROR-PROTECT is used by ERROR and friends to keep us out
+;;; of hyperspace.
(defmacro infinite-error-protect (&rest forms)
`(unless (infinite-error-protector)
+ (/show0 "back from INFINITE-ERROR-PROTECTOR")
(let ((*current-error-depth* (1+ *current-error-depth*)))
+ (/show0 "in INFINITE-ERROR-PROTECT, incremented error depth")
+ ;; arbitrary truncation
+ #!+sb-show (sb!debug:backtrace 8)
,@forms)))
;;; a helper function for INFINITE-ERROR-PROTECT
(defun infinite-error-protector ()
+ (/show0 "entering INFINITE-ERROR-PROTECTOR, *CURRENT-ERROR-DEPTH*=..")
+ (/hexstr *current-error-depth*)
(cond ((not *cold-init-complete-p*)
(%primitive print "Argh! error in cold init, halting")
(%primitive sb!c:halt))
(%primitive print "Argh! corrupted error depth, halting")
(%primitive sb!c:halt))
((> *current-error-depth* *maximum-error-depth*)
+ (/show0 "*MAXIMUM-ERROR-DEPTH*=..")
+ (/hexstr *maximum-error-depth*)
(/show0 "in INFINITE-ERROR-PROTECTOR, calling ERROR-ERROR")
(error-error "Help! "
*current-error-depth*
"KERNEL:*MAXIMUM-ERROR-DEPTH* exceeded.")
t)
(t
+ (/show0 "returning normally from INFINITE-ERROR-PROTECTOR")
nil)))
;;; FIXME: I had a badly broken version of INFINITE-ERROR-PROTECTOR at
\f
;;;; miscellaneous external functions
-#!-mp ; The multi-processing version is defined in multi-proc.lisp.
(defun sleep (n)
#!+sb-doc
"This function causes execution to be suspended for N seconds. N may
be any non-negative, non-complex number."
(when (or (not (realp n))
(minusp n))
- (error "Invalid argument to SLEEP: ~S.~%~
- Must be a non-negative, non-complex number."
- n))
+ (error 'simple-type-error
+ :format-control "invalid argument to SLEEP: ~S"
+ :format-arguments (list n)
+ :datum n
+ :expected-type '(real 0)))
(multiple-value-bind (sec usec)
(if (integerp n)
(values n 0)
(multiple-value-bind (sec frac)
(truncate n)
- (values sec(truncate frac 1e-6))))
+ (values sec (truncate frac 1e-6))))
(sb!unix:unix-select 0 0 0 0 sec usec))
nil)
\f
(defconstant bytes-per-scrub-unit 2048)
+;;; Zero the unused portion of the control stack so that old objects
+;;; are not kept alive because of uninitialized stack variables.
+
+;;; "To summarize the problem, since not all allocated stack frame
+;;; slots are guaranteed to be written by the time you call an another
+;;; function or GC, there may be garbage pointers retained in your
+;;; dead stack locations. The stack scrubbing only affects the part
+;;; of the stack from the SP to the end of the allocated stack."
+;;; - ram, on cmucl-imp, Tue, 25 Sep 2001
+
+;;; So, as an (admittedly lame) workaround, from time to time we call
+;;; scrub-control-stack to zero out all the unused portion. This is
+;;; supposed to happen when the stack is mostly empty, so that we have
+;;; a chance of clearing more of it: callers are currently (2002.07.18)
+;;; REPL and SUB-GC
+
(defun scrub-control-stack ()
- #!+sb-doc
- "Zero the unused portion of the control stack so that old objects are not
- kept alive because of uninitialized stack variables."
- ;; FIXME: Why do we need to do this instead of just letting GC read
- ;; the stack pointer and avoid messing with the unused portion of
- ;; the control stack? (Is this a multithreading thing where there's
- ;; one control stack and stack pointer per thread, and it might not
- ;; be easy to tell what a thread's stack pointer value is when
- ;; looking in from another thread?)
(declare (optimize (speed 3) (safety 0))
(values (unsigned-byte 20))) ; FIXME: DECLARE VALUES?
- #!-x86 ; machines where stack grows upwards (I guess) -- WHN 19990906
- (labels
- ((scrub (ptr offset count)
- (declare (type system-area-pointer ptr)
- (type (unsigned-byte 16) offset)
- (type (unsigned-byte 20) count)
- (values (unsigned-byte 20)))
- (cond ((= offset bytes-per-scrub-unit)
- (look (sap+ ptr bytes-per-scrub-unit) 0 count))
- (t
- (setf (sap-ref-32 ptr offset) 0)
- (scrub ptr (+ offset sb!vm:word-bytes) count))))
- (look (ptr offset count)
- (declare (type system-area-pointer ptr)
- (type (unsigned-byte 16) offset)
- (type (unsigned-byte 20) count)
- (values (unsigned-byte 20)))
- (cond ((= offset bytes-per-scrub-unit)
- count)
- ((zerop (sap-ref-32 ptr offset))
- (look ptr (+ offset sb!vm:word-bytes) count))
- (t
- (scrub ptr offset (+ count sb!vm:word-bytes))))))
- (let* ((csp (sap-int (sb!c::control-stack-pointer-sap)))
- (initial-offset (logand csp (1- bytes-per-scrub-unit))))
+ #!-stack-grows-downward-not-upward
+ (let* ((csp (sap-int (sb!c::control-stack-pointer-sap)))
+ (initial-offset (logand csp (1- bytes-per-scrub-unit)))
+ (end-of-stack
+ (- sb!vm::*control-stack-end* sb!c:*backend-page-size*)))
+ (labels
+ ((scrub (ptr offset count)
+ (declare (type system-area-pointer ptr)
+ (type (unsigned-byte 16) offset)
+ (type (unsigned-byte 20) count)
+ (values (unsigned-byte 20)))
+ (cond ((>= (sap-int ptr) end-of-stack) 0)
+ ((= offset bytes-per-scrub-unit)
+ (look (sap+ ptr bytes-per-scrub-unit) 0 count))
+ (t
+ (setf (sap-ref-32 ptr offset) 0)
+ (scrub ptr (+ offset sb!vm:n-word-bytes) count))))
+ (look (ptr offset count)
+ (declare (type system-area-pointer ptr)
+ (type (unsigned-byte 16) offset)
+ (type (unsigned-byte 20) count)
+ (values (unsigned-byte 20)))
+ (cond ((>= (sap-int ptr) end-of-stack) 0)
+ ((= offset bytes-per-scrub-unit)
+ count)
+ ((zerop (sap-ref-32 ptr offset))
+ (look ptr (+ offset sb!vm:n-word-bytes) count))
+ (t
+ (scrub ptr offset (+ count sb!vm:n-word-bytes))))))
(declare (type (unsigned-byte 32) csp))
(scrub (int-sap (- csp initial-offset))
- (* (floor initial-offset sb!vm:word-bytes) sb!vm:word-bytes)
+ (* (floor initial-offset sb!vm:n-word-bytes) sb!vm:n-word-bytes)
0)))
- #!+x86 ;; (Stack grows downwards.)
- (labels
- ((scrub (ptr offset count)
- (declare (type system-area-pointer ptr)
- (type (unsigned-byte 16) offset)
- (type (unsigned-byte 20) count)
- (values (unsigned-byte 20)))
- (let ((loc (int-sap (- (sap-int ptr) (+ offset sb!vm:word-bytes)))))
- (cond ((= offset bytes-per-scrub-unit)
- (look (int-sap (- (sap-int ptr) bytes-per-scrub-unit))
- 0 count))
- (t ;; need to fix bug in %SET-STACK-REF
- (setf (sap-ref-32 loc 0) 0)
- (scrub ptr (+ offset sb!vm:word-bytes) count)))))
- (look (ptr offset count)
- (declare (type system-area-pointer ptr)
- (type (unsigned-byte 16) offset)
- (type (unsigned-byte 20) count)
- (values (unsigned-byte 20)))
- (let ((loc (int-sap (- (sap-int ptr) offset))))
- (cond ((= offset bytes-per-scrub-unit)
- count)
- ((zerop (sb!kernel::get-lisp-obj-address (stack-ref loc 0)))
- (look ptr (+ offset sb!vm:word-bytes) count))
- (t
- (scrub ptr offset (+ count sb!vm:word-bytes)))))))
- (let* ((csp (sap-int (sb!c::control-stack-pointer-sap)))
- (initial-offset (logand csp (1- bytes-per-scrub-unit))))
+ #!+stack-grows-downward-not-upward
+ (let* ((csp (sap-int (sb!c::control-stack-pointer-sap)))
+ (end-of-stack (+ sb!vm::*control-stack-start* sb!c:*backend-page-size*))
+ (initial-offset (logand csp (1- bytes-per-scrub-unit))))
+ (labels
+ ((scrub (ptr offset count)
+ (declare (type system-area-pointer ptr)
+ (type (unsigned-byte 16) offset)
+ (type (unsigned-byte 20) count)
+ (values (unsigned-byte 20)))
+ (let ((loc (int-sap (- (sap-int ptr) (+ offset sb!vm:n-word-bytes)))))
+ (cond ((< (sap-int loc) end-of-stack) 0)
+ ((= offset bytes-per-scrub-unit)
+ (look (int-sap (- (sap-int ptr) bytes-per-scrub-unit))
+ 0 count))
+ (t ;; need to fix bug in %SET-STACK-REF
+ (setf (sap-ref-32 loc 0) 0)
+ (scrub ptr (+ offset sb!vm:n-word-bytes) count)))))
+ (look (ptr offset count)
+ (declare (type system-area-pointer ptr)
+ (type (unsigned-byte 16) offset)
+ (type (unsigned-byte 20) count)
+ (values (unsigned-byte 20)))
+ (let ((loc (int-sap (- (sap-int ptr) offset))))
+ (cond ((< (sap-int loc) end-of-stack) 0)
+ ((= offset bytes-per-scrub-unit)
+ count)
+ ((zerop (sb!kernel::get-lisp-obj-address (stack-ref loc 0)))
+ (look ptr (+ offset sb!vm:n-word-bytes) count))
+ (t
+ (scrub ptr offset (+ count sb!vm:n-word-bytes)))))))
(declare (type (unsigned-byte 32) csp))
(scrub (int-sap (+ csp initial-offset))
- (* (floor initial-offset sb!vm:word-bytes) sb!vm:word-bytes)
+ (* (floor initial-offset sb!vm:n-word-bytes) sb!vm:n-word-bytes)
0))))
\f
-;;;; the default TOPLEVEL function
+;;;; the default toplevel function
(defvar / nil
#!+sb-doc
- "a list of all the values returned by the most recent top-level EVAL")
+ "a list of all the values returned by the most recent top level EVAL")
(defvar // nil #!+sb-doc "the previous value of /")
(defvar /// nil #!+sb-doc "the previous value of //")
-(defvar * nil #!+sb-doc "the value of the most recent top-level EVAL")
+(defvar * nil #!+sb-doc "the value of the most recent top level EVAL")
(defvar ** nil #!+sb-doc "the previous value of *")
(defvar *** nil #!+sb-doc "the previous value of **")
-(defvar + nil #!+sb-doc "the value of the most recent top-level READ")
+(defvar + nil #!+sb-doc "the value of the most recent top level READ")
(defvar ++ nil #!+sb-doc "the previous value of +")
(defvar +++ nil #!+sb-doc "the previous value of ++")
(defvar - nil #!+sb-doc "the form currently being evaluated")
-(defvar *prompt* "* "
- #!+sb-doc
- "The top-level prompt string. This also may be a function of no arguments
- that returns a simple-string.")
-(defvar *in-top-level-catcher* nil
- #!+sb-doc
- "Are we within the Top-Level-Catcher? This is used by interrupt
- handlers to see whether it is OK to throw.")
(defun interactive-eval (form)
"Evaluate FORM, returning whatever it returns and adjusting ***, **, *,
+++, ++, +, ///, //, /, and -."
(setf - form)
- (let ((results (multiple-value-list (eval form))))
+ (let ((results
+ (multiple-value-list
+ (eval-in-lexenv form
+ (make-null-interactive-lexenv)))))
(setf /// //
// /
/ results
(finish-output (symbol-value name)))
(values))
-;;; the default system top-level function
-(defun toplevel ()
+;;; the default system top level function
+(defun toplevel-init ()
- (/show0 "entering TOPLEVEL")
-
- (let ((sysinit nil) ; value of --sysinit option
- (userinit nil) ; value of --userinit option
- (evals nil) ; values of --eval options (in reverse order)
- (noprint nil) ; Has a --noprint option been seen?
- (noprogrammer nil) ; Has a --noprogammer option been seen?
+ (/show0 "entering TOPLEVEL-INIT")
+ (setf sb!thread::*session-lock* (sb!thread:make-mutex :name "the terminal"))
+ (sb!thread::get-foreground)
+ (let ((sysinit nil) ; value of --sysinit option
+ (userinit nil) ; value of --userinit option
+ (reversed-evals nil) ; values of --eval options, in reverse order; and
+ ; also --load options, translated into --eval
+ (noprint nil) ; Has a --noprint option been seen?
(options (rest *posix-argv*))) ; skipping program name
- (/show0 "done with outer LET in TOPLEVEL")
-
- ;; FIXME: There are lots of ways for errors to happen around here (e.g. bad
- ;; command line syntax, or READ-ERROR while trying to READ an --eval
- ;; string). Make sure that they're handled reasonably.
+ (declare (type list options))
+ (/show0 "done with outer LET in TOPLEVEL-INIT")
+
+ ;; FIXME: There are lots of ways for errors to happen around here
+ ;; (e.g. bad command line syntax, or READ-ERROR while trying to
+ ;; READ an --eval string). Make sure that they're handled
+ ;; reasonably. Also, perhaps all errors while parsing the command
+ ;; line should cause the system to QUIT, instead of trying to go
+ ;; into the Lisp debugger, since trying to go into the debugger
+ ;; gets into various annoying issues of where we should go after
+ ;; the user tries to return from the debugger.
+
;; Parse command line options.
(loop while options do
- (/show0 "at head of LOOP WHILE OPTIONS DO in TOPLEVEL")
+ (/show0 "at head of LOOP WHILE OPTIONS DO in TOPLEVEL-INIT")
(let ((option (first options)))
(flet ((pop-option ()
(if options
(error "more than one expression in ~S"
eval-as-string))
(t
- (push eval evals)))))))
+ (push eval reversed-evals)))))))
+ ((string= option "--load")
+ (pop-option)
+ (push `(load ,(pop-option)) reversed-evals))
((string= option "--noprint")
(pop-option)
(setf noprint t))
+ ;; FIXME: --noprogrammer was deprecated in 0.7.5, and
+ ;; in a year or so this backwards compatibility can
+ ;; go away.
((string= option "--noprogrammer")
+ (warn "treating deprecated --noprogrammer as --disable-debugger")
+ (pop-option)
+ (push '(disable-debugger) reversed-evals))
+ ((string= option "--disable-debugger")
(pop-option)
- (setf noprogrammer t))
+ (push '(disable-debugger) reversed-evals))
((string= option "--end-toplevel-options")
(pop-option)
(return))
;; because we didn't recognize an option as a
;; toplevel option, then the option we gave up on
;; must have been an error. (E.g. in
- ;; sbcl --eval '(a)' --evl '(b)' --end-toplevel-options
- ;; this test will let us detect that "--evl" is
- ;; an error.)
+ ;; "sbcl --eval '(a)' --eval'(b)' --end-toplevel-options"
+ ;; this test will let us detect that the string
+ ;; "--eval(b)" is an error.)
(if (find "--end-toplevel-options" options
:test #'string=)
(error "bad toplevel option: ~S" (first options))
(return)))))))
- (/show0 "done with LOOP WHILE OPTIONS DO in TOPLEVEL")
+ (/show0 "done with LOOP WHILE OPTIONS DO in TOPLEVEL-INIT")
- ;; Excise all the options that we processed, so that only user-level
- ;; options are left visible to user code.
+ ;; Excise all the options that we processed, so that only
+ ;; user-level options are left visible to user code.
(setf (rest *posix-argv*) options)
- ;; FIXME: Verify that errors in init files and/or --eval operations
- ;; lead to reasonable behavior.
-
;; Handle initialization files.
- (/show0 "handling initialization files in TOPLEVEL")
+ (/show0 "handling initialization files in TOPLEVEL-INIT")
(flet (;; If any of POSSIBLE-INIT-FILE-NAMES names a real file,
;; return its truename.
(probe-init-files (&rest possible-init-file-names)
+ (declare (type list possible-init-file-names))
(/show0 "entering PROBE-INIT-FILES")
(prog1
(find-if (lambda (x)
possible-init-file-names)
(/show0 "leaving PROBE-INIT-FILES"))))
(let* ((sbcl-home (posix-getenv "SBCL_HOME"))
- #!+sb-show(ignore1 (progn
- (/show0 "SBCL-HOME=..")
- (if sbcl-home
- (%primitive print sbcl-home)
- (%primitive print "NIL"))))
(sysinit-truename (if sbcl-home
(probe-init-files sysinit
- (concatenate
- 'string
- sbcl-home
- "/sbclrc"))
+ (concatenate 'string
+ sbcl-home
+ "/sbclrc"))
(probe-init-files sysinit
"/etc/sbclrc"
"/usr/local/etc/sbclrc")))
(user-home (or (posix-getenv "HOME")
(error "The HOME environment variable is unbound, ~
so user init file can't be found.")))
- #!+sb-show(ignore2 (progn
- (/show0 "USER-HOME=..")
- (%primitive print user-home)))
(userinit-truename (probe-init-files userinit
- (concatenate
- 'string
- user-home
- "/.sbclrc"))))
- (/show0 "assigned SYSINIT-TRUENAME and USERINIT-TRUENAME")
- (when sysinit-truename
- (/show0 "SYSINIT-TRUENAME=..")
- #!+sb-show (%primitive print sysinit-truename)
- (unless (load sysinit-truename)
- (error "~S was not successfully loaded." sysinit-truename))
- (flush-standard-output-streams))
- (/show0 "loaded SYSINIT-TRUENAME")
- (when userinit-truename
- (/show0 "USERINIT-TRUENAME=..")
- #!+sb-show (%primitive print userinit-truename)
- (unless (load userinit-truename)
- (error "~S was not successfully loaded." userinit-truename))
- (flush-standard-output-streams))
- (/show0 "loaded USERINIT-TRUENAME"))
-
- ;; Handle --eval options.
- (/show0 "handling --eval options in TOPLEVEL")
- (dolist (eval (reverse evals))
- (/show0 "handling one --eval option in TOPLEVEL")
- (eval eval)
- (flush-standard-output-streams))
-
- ;; Handle stream binding controlled by --noprogrammer option.
- ;;
- ;; FIXME: When we do actually implement this, shouldn't it go
- ;; earlier in the sequence, so that its stream bindings will
- ;; affect the behavior of init files and --eval options?
- (/show0 "handling --noprogrammer option in TOPLEVEL")
- (when noprogrammer
- (warn "stub: --noprogrammer option unimplemented")) ; FIXME
-
- (/show0 "falling into TOPLEVEL-REPL from TOPLEVEL")
- (toplevel-repl noprint))))
+ (concatenate 'string
+ user-home
+ "/.sbclrc"))))
+
+ ;; We wrap all the pre-REPL user/system customized startup code
+ ;; in a restart.
+ ;;
+ ;; (Why not wrap everything, even the stuff above, in this
+ ;; restart? Errors above here are basically command line or
+ ;; Unix environment errors, e.g. a missing file or a typo on
+ ;; the Unix command line, and you don't need to get into Lisp
+ ;; to debug them, you should just start over and do it right
+ ;; at the Unix level. Errors below here are generally errors
+ ;; in user Lisp code, and it might be helpful to let the user
+ ;; reach the REPL in order to help figure out what's going
+ ;; on.)
+ (restart-case
+ (progn
+ (flet ((process-init-file (truename)
+ (when truename
+ (unless (load truename)
+ (error "~S was not successfully loaded." truename))
+ (flush-standard-output-streams))))
+ (process-init-file sysinit-truename)
+ (process-init-file userinit-truename))
+
+ ;; Process --eval options.
+ (/show0 "handling --eval options in TOPLEVEL-INIT")
+ (dolist (eval (reverse reversed-evals))
+ (/show0 "handling one --eval option in TOPLEVEL-INIT")
+ (eval eval)
+ (flush-standard-output-streams)))
+ (continue ()
+ :report
+ "Continue anyway (skipping to toplevel read/eval/print loop)."
+ (/show0 "CONTINUEing from pre-REPL RESTART-CASE")
+ (values)) ; (no-op, just fall through)
+ (quit ()
+ :report "Quit SBCL (calling #'QUIT, killing the process)."
+ (/show0 "falling through to QUIT from pre-REPL RESTART-CASE")
+ (quit))))
+
+ ;; one more time for good measure, in case we fell out of the
+ ;; RESTART-CASE above before one of the flushes in the ordinary
+ ;; flow of control had a chance to operate
+ (flush-standard-output-streams)
+
+ (/show0 "falling into TOPLEVEL-REPL from TOPLEVEL-INIT")
+ (toplevel-repl noprint)
+ ;; (classic CMU CL error message: "You're certainly a clever child.":-)
+ (critically-unreachable "after TOPLEVEL-REPL"))))
+
+;;; halt-on-failures and prompt-on-failures modes, suitable for
+;;; noninteractive and interactive use respectively
+(defun disable-debugger ()
+ (setf *debugger-hook* 'noprogrammer-debugger-hook-fun
+ *debug-io* *error-output*))
+(defun enable-debugger ()
+ (setf *debugger-hook* nil
+ *debug-io* *query-io*))
;;; read-eval-print loop for the default system toplevel
(defun toplevel-repl (noprint)
(let ((* nil) (** nil) (*** nil)
(- nil)
(+ nil) (++ nil) (+++ nil)
- (/// nil) (// nil) (/ nil)
- (eof-marker (cons :eof nil)))
+ (/// nil) (// nil) (/ nil))
+ ;; WITH-SIMPLE-RESTART doesn't actually restart its body as some
+ ;; (like WHN for an embarrassingly long time ca. 2001-12-07) might
+ ;; think, but instead drops control back out at the end. So when a
+ ;; TOPLEVEL or outermost-ABORT restart happens, we need this outer
+ ;; LOOP wrapper to grab control and start over again. (And it also
+ ;; wraps CATCH 'TOPLEVEL-CATCHER for similar reasons.)
+ (loop
+ (/show0 "about to set up restarts in TOPLEVEL-REPL")
+ ;; There should only be one TOPLEVEL restart, and it's here, so
+ ;; restarting at TOPLEVEL always bounces you all the way out here.
+ (with-simple-restart (toplevel
+ "Restart at toplevel READ/EVAL/PRINT loop.")
+ ;; We add a new ABORT restart for every debugger level, so
+ ;; restarting at ABORT in a nested debugger gets you out to the
+ ;; innermost enclosing debugger, and only when you're in the
+ ;; outermost, unnested debugger level does restarting at ABORT
+ ;; get you out to here.
+ (with-simple-restart
+ (abort
+ "~@<Reduce debugger level (leaving debugger, returning to toplevel).~@:>")
+ (catch 'toplevel-catcher
+ #!-sunos (sb!unix:unix-sigsetmask 0) ; FIXME: What is this for?
+ ;; in the event of a control-stack-exhausted-error, we should
+ ;; have unwound enough stack by the time we get here that this
+ ;; is now possible
+ (sb!kernel::protect-control-stack-guard-page 1)
+ (repl noprint)
+ (critically-unreachable "after REPL")))))))
+
+;;; Our default REPL prompt is the minimal traditional one.
+(defun repl-prompt-fun (stream)
+ (fresh-line stream)
+ (write-string "* " stream)) ; arbitrary but customary REPL prompt
+
+;;; Our default form reader does relatively little magic, but does
+;;; handle the Unix-style EOF-is-end-of-process convention.
+(defun repl-read-form-fun (in out)
+ (declare (type stream in out) (ignore out))
+ (let* ((eof-marker (cons nil nil))
+ (form (read in nil eof-marker)))
+ (if (eq form eof-marker)
+ (quit)
+ form)))
+
+;;; hooks to support customized toplevels like ACL-style toplevel
+;;; from KMR on sbcl-devel 2002-12-21
+(defvar *repl-read-form-fun* #'repl-read-form-fun
+ "a function of two stream arguments IN and OUT for the toplevel REPL to
+ call: Return the next Lisp form to evaluate (possibly handling other
+ magic -- like ACL-style keyword commands -- which precede the next
+ Lisp form). The OUT stream is there to support magic which requires
+ issuing new prompts.")
+(defvar *repl-prompt-fun* #'repl-prompt-fun
+ "a function of one argument STREAM for the toplevel REPL to call: Prompt
+ the user for input.")
+
+(defun repl (noprint)
+ (/show0 "entering REPL")
+ (let ((eof-marker (cons :eof nil)))
(loop
- ;; FIXME: This seems to be the source of one of the basic debugger
- ;; choices in
- ;; Restarts:
- ;; 0: [CONTINUE] Return from BREAK.
- ;; 1: [ABORT ] Return to toplevel.
- ;; (The "Return from BREAK" choice is defined in BREAK.) I'd like to add
- ;; another choice,
- ;; 2: [TERMINATE] Terminate the current Lisp.
- ;; That way, a user hitting ^C could get out of Lisp without knowing
- ;; enough about the system to run (SB-EXT:QUIT).
- ;;
- ;; If I understand the documentation of WITH-SIMPLE-RESTART correctly,
- ;; it shows how to replace this WITH-SIMPLE-RESTART with a RESTART-CASE
- ;; with two choices (ABORT and QUIT). Or perhaps ABORT should be renamed
- ;; TOPLEVEL?
- ;; Restarts:
- ;; 0: [CONTINUE ] Return from BREAK, continuing calculation
- ;; as though nothing happened.
- ;; 1: [TOPLEVEL ] Transfer control to toplevel read/eval/print
- ;; loop, aborting current calculation.
- ;; 2: [TERMINATE] Terminate the current Lisp (equivalent to
- ;; executing (SB-EXT:QUIT)).
- (/show0 "at head of outer LOOP in TOPLEVEL-REPL")
- (with-simple-restart (abort "Return to toplevel.")
- (catch 'top-level-catcher
- (sb!unix:unix-sigsetmask 0) ; FIXME: What is this for?
- (let ((*in-top-level-catcher* t))
- (/show0 "about to enter inner LOOP in TOPLEVEL-REPL")
- (loop ; FIXME: Do we need this inner LOOP?
- ;; FIXME: It seems bad to have GC behavior depend on scrubbing
- ;; the control stack before each interactive command. Isn't
- ;; there some way we can convince the GC to just ignore
- ;; dead areas of the control stack, so that we don't need to
- ;; rely on this half-measure?
- (scrub-control-stack)
- (unless noprint
- (fresh-line)
- (princ (if (functionp *prompt*)
- (funcall *prompt*)
- *prompt*))
- (flush-standard-output-streams))
- (let ((form (read *standard-input* nil eof-marker)))
- (if (eq form eof-marker)
- (quit)
- (let ((results
- (multiple-value-list (interactive-eval form))))
- (unless noprint
- (dolist (result results)
- (fresh-line)
- (prin1 result)))))))))))))
+ ;; (See comment preceding the definition of SCRUB-CONTROL-STACK.)
+ (scrub-control-stack)
+ (unless noprint
+ (funcall *repl-prompt-fun* *standard-output*)
+ ;; (Should *REPL-PROMPT-FUN* be responsible for doing its own
+ ;; FORCE-OUTPUT? I can't imagine a valid reason for it not to
+ ;; be done here, so leaving it up to *REPL-PROMPT-FUN* seems
+ ;; odd. But maybe there *is* a valid reason in some
+ ;; circumstances? perhaps some deadlock issue when being driven
+ ;; by another process or something...)
+ (force-output *standard-output*))
+ (let* ((form (funcall *repl-read-form-fun*
+ *standard-input*
+ *standard-output*))
+ (results (multiple-value-list (interactive-eval form))))
+ (unless noprint
+ (dolist (result results)
+ (fresh-line)
+ (prin1 result)))))))
+
+;;; suitable value for *DEBUGGER-HOOK* for a noninteractive Unix-y program
+(defun noprogrammer-debugger-hook-fun (condition old-debugger-hook)
+ (declare (ignore old-debugger-hook))
+ (flet ((failure-quit (&key recklessly-p)
+ (/show0 "in FAILURE-QUIT (in --disable-debugger debugger hook)")
+ (quit :unix-status 1 :recklessly-p recklessly-p)))
+ ;; This HANDLER-CASE is here mostly to stop output immediately
+ ;; (and fall through to QUIT) when there's an I/O error. Thus,
+ ;; when we're run under a shell script or something, we can die
+ ;; cleanly when the script dies (and our pipes are cut), instead
+ ;; of falling into ldb or something messy like that.
+ (handler-case
+ (progn
+ (format *error-output*
+ "~&~@<unhandled condition (of type ~S): ~2I~_~A~:>~2%"
+ (type-of condition)
+ condition)
+ ;; Flush *ERROR-OUTPUT* even before the BACKTRACE, so that
+ ;; even if we hit an error within BACKTRACE (e.g. a bug in
+ ;; the debugger's own frame-walking code, or a bug in a user
+ ;; PRINT-OBJECT method) we'll at least have the CONDITION
+ ;; printed out before we die.
+ (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*)
+ (format
+ *error-output*
+ "~%unhandled condition in --disable-debugger mode, quitting~%")
+ (finish-output *error-output*)
+ (failure-quit))
+ (condition ()
+ ;; We IGNORE-ERRORS here because even %PRIMITIVE PRINT can
+ ;; fail when our output streams are blown away, as e.g. when
+ ;; we're running under a Unix shell script and it dies somehow
+ ;; (e.g. because of a SIGINT). In that case, we might as well
+ ;; just give it up for a bad job, and stop trying to notify
+ ;; the user of anything.
+ ;;
+ ;; Actually, the only way I've run across to exercise the
+ ;; problem is to have more than one layer of shell script.
+ ;; I have a shell script which does
+ ;; time nice -10 sh make.sh "$1" 2>&1 | tee make.tmp
+ ;; and the problem occurs when I interrupt this with Ctrl-C
+ ;; under Linux 2.2.14-5.0 and GNU bash, version 1.14.7(1).
+ ;; I haven't figured out whether it's bash, time, tee, Linux, or
+ ;; what that is responsible, but that it's possible at all
+ ;; means that we should IGNORE-ERRORS here. -- WHN 2001-04-24
+ (ignore-errors
+ (%primitive print
+ "Argh! error within --disable-debugger error handling"))
+ (failure-quit :recklessly-p t)))))
\f
;;; a convenient way to get into the assembly-level debugger
(defun %halt ()