;;;; files for more information.
(in-package "SB!IMPL")
-
-(file-comment
- "$Header$")
\f
(defconstant most-positive-fixnum #.sb!vm:*target-most-positive-fixnum*
#!+sb-doc
(defvar *maximum-error-depth*)
(defvar *current-error-depth*)
\f
+;;;; miscellaneous utilities for working with with TOPLEVEL
+
+;;; Execute BODY in a context where any %END-OF-THE-WORLD (thrown e.g.
+;;; by QUIT) is caught and any final processing and return codes are
+;;; handled appropriately.
+(defmacro handling-end-of-the-world (&body body)
+ (let ((caught (gensym "CAUGHT")))
+ `(let ((,caught (catch '%end-of-the-world
+ (/show0 "inside CATCH '%END-OF-THE-WORLD")
+ (restart-case (progn ,@body)
+ ;; KLUDGE: I'd like to name this restart QUIT,
+ ;; but then people would hate me, since in CMU
+ ;; CL, even though they have essentially the
+ ;; same QUIT function as SBCL, the "QUIT"
+ ;; command in the debugger means to return to
+ ;; the toplevel, not to actually call QUIT. Oh
+ ;; well. -- WHN 2000-11-01
+ (end-of-the-world ()
+ :report (lambda (s)
+ (format s
+ "Terminate the current Lisp, ~
+ like #'~S."
+ 'quit))
+ (quit))))))
+ (/show0 "back from CATCH '%END-OF-THE-WORLD, flushing output")
+ (flush-standard-output-streams)
+ (/show0 "calling UNIX-EXIT")
+ (sb!unix:unix-exit ,caught))))
+\f
;;;; working with *CURRENT-ERROR-DEPTH* and *MAXIMUM-ERROR-DEPTH*
;;; INFINITE-ERROR-PROTECT is used by ERROR and friends to keep us out of
(* (floor initial-offset sb!vm:word-bytes) sb!vm:word-bytes)
0))))
\f
-;;;; the default TOPLEVEL function
+;;;; the default toplevel function
(defvar / nil
#!+sb-doc
#!+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 ***, **, *,
(values))
;;; the default system top-level function
-(defun toplevel ()
+(defun toplevel-init ()
- (/show0 "entering TOPLEVEL")
+ (/show0 "entering TOPLEVEL-INIT")
(let ((sysinit nil) ; value of --sysinit option
(userinit nil) ; value of --userinit option
(noprogrammer nil) ; Has a --noprogammer option been seen?
(options (rest *posix-argv*))) ; skipping program name
- (/show0 "done with outer LET in TOPLEVEL")
+ (/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
;; 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
: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.
;; 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)
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
(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
"/.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")))
+ (/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 --eval options.
+ (/show0 "handling --eval options in TOPLEVEL-INIT")
+ (dolist (eval (reverse evals))
+ (/show0 "handling one --eval option in TOPLEVEL-INIT")
+ (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
+ ;; 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-INIT")
+ (when noprogrammer
+ (warn "stub: --noprogrammer option unimplemented")) ; FIXME
- (/show0 "falling into TOPLEVEL-REPL from TOPLEVEL")
- (toplevel-repl noprint)))
+ (/show0 "falling into TOPLEVEL-REPL from TOPLEVEL-INIT")
+ (toplevel-repl noprint))))
;;; read-eval-print loop for the default system toplevel
(defun toplevel-repl (noprint)
(/// nil) (// nil) (/ nil)
(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)))))))))))))
+ ;; 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).")
+ (catch 'top-level-catcher
+ (sb!unix:unix-sigsetmask 0) ; FIXME: What is this for?
+ (/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)))))))))))))
\f
;;; a convenient way to get into the assembly-level debugger
(defun %halt ()