;;;; Guile Debugger command loop ;;; Copyright (C) 1999, 2001, 2002 Free Software Foundation, Inc. ;;; ;;; This program is free software; you can redistribute it and/or ;;; modify it under the terms of the GNU General Public License as ;;; published by the Free Software Foundation; either version 2, or ;;; (at your option) any later version. ;;; ;;; This program is distributed in the hope that it will be useful, ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ;;; General Public License for more details. ;;; ;;; You should have received a copy of the GNU General Public License ;;; along with this software; see the file COPYING. If not, write to ;;; the Free Software Foundation, Inc., 59 Temple Place, Suite 330, ;;; Boston, MA 02111-1307 USA ;;; ;;; As a special exception, the Free Software Foundation gives permission ;;; for additional uses of the text contained in its release of GUILE. ;;; ;;; The exception is that, if you link the GUILE library with other files ;;; to produce an executable, this does not by itself cause the ;;; resulting executable to be covered by the GNU General Public License. ;;; Your use of that executable is in no way restricted on account of ;;; linking the GUILE library code into it. ;;; ;;; This exception does not however invalidate any other reasons why ;;; the executable file might be covered by the GNU General Public License. ;;; ;;; This exception applies only to the code released by the ;;; Free Software Foundation under the name GUILE. If you copy ;;; code from other Free Software Foundation releases into a copy of ;;; GUILE, as the General Public License permits, the exception does ;;; not apply to the code that you add in this way. To avoid misleading ;;; anyone as to the status of such modified files, you must delete ;;; this exception notice from them. ;;; ;;; If you write modifications of your own for GUILE, it is your choice ;;; whether to permit this exception to apply to your modifications. ;;; If you do not wish that, delete this exception notice. (define-module (ice-9 debugger command-loop) #:use-module (ice-9 debugger commands) #:export (debugger-command-loop debugger-command-loop-error debugger-command-loop-quit) #:no-backtrace) (if (memq 'readline *features*) (define-module (ice-9 debugger command-loop) :use-module (ice-9 readline))) ;;; {Interface used by (ice-9 debugger).} (define (debugger-command-loop state) (read-and-dispatch-commands state (current-input-port))) (define (debugger-command-loop-error message) (user-error message)) (define (debugger-command-loop-quit) (throw 'exit-debugger)) ;;; {Implementation.} (define debugger-prompt "debug> ") (define (debugger-handler key . args) (case key ((exit-debugger) #f) ((signal) ;; Restore stack (fluid-set! the-last-stack (fluid-ref before-signal-stack)) (apply display-error #f (current-error-port) args)) (else (display "Internal debugger error:\n") (save-stack debugger-handler) (apply throw key args))) (throw 'exit-debugger)) ;Pop the stack (define (read-and-dispatch-commands state port) (catch 'exit-debugger (lambda () (lazy-catch #t (lambda () (with-fluids ((last-command #f)) (let loop () (read-and-dispatch-command state port) (loop)))) debugger-handler)) (lambda args *unspecified*))) (define (read-and-dispatch-command state port) (if (using-readline?) (set-readline-prompt! debugger-prompt debugger-prompt) (display debugger-prompt)) (force-output) ;This should not be necessary... (let ((token (read-token port))) (cond ((eof-object? token) (throw 'exit-debugger)) ((not token) (discard-rest-of-line port) (catch-user-errors port (lambda () (run-last-command state)))) (else (catch-user-errors port (lambda () (dispatch-command token command-table state port))))))) (define (run-last-command state) (let ((procedure (fluid-ref last-command))) (if procedure (procedure state)))) (define (catch-user-errors port thunk) (catch 'debugger-user-error thunk (lambda (key . objects) (apply user-warning objects) (discard-rest-of-line port)))) (define last-command (make-fluid)) (define (user-warning . objects) (for-each (lambda (object) (display object)) objects) (newline)) (define (user-error . objects) (apply throw 'debugger-user-error objects)) ;;;; Command dispatch (define (dispatch-command string table state port) (let ((value (command-table-value table string))) (if value (dispatch-command/value value state port) (user-error "Unknown command: " string)))) (define (dispatch-command/value value state port) (cond ((command? value) (dispatch-command/command value state port)) ((command-table? value) (dispatch-command/table value state port)) ((list? value) (dispatch-command/name value state port)) (else (error "Unrecognized command-table value: " value)))) (define (dispatch-command/command command state port) (let ((procedure (command-procedure command)) (arguments ((command-parser command) port))) (let ((procedure (lambda (state) (apply procedure state arguments)))) (warn-about-extra-args port) (fluid-set! last-command procedure) (procedure state)))) (define (warn-about-extra-args port) ;; **** modify this to show the arguments. (let ((char (skip-whitespace port))) (cond ((eof-object? char) #f) ((char=? #\newline char) (read-char port)) (else (user-warning "Extra arguments at end of line: " (read-rest-of-line port)))))) (define (dispatch-command/table table state port) (let ((token (read-token port))) (if (or (eof-object? token) (not token)) (user-error "Command name too short.") (dispatch-command token table state port)))) (define (dispatch-command/name name state port) (let ((value (lookup-command name))) (cond ((not value) (apply user-error "Unknown command name: " name)) ((command-table? value) (apply user-error "Partial command name: " name)) (else (dispatch-command/value value state port))))) ;;;; Command definition (define (define-command name argument-template procedure) (let ((name (canonicalize-command-name name))) (add-command name (make-command name (argument-template->parser argument-template) (procedure-documentation procedure) procedure) command-table) name)) (define (define-command-alias name1 name2) (let ((name1 (canonicalize-command-name name1))) (add-command name1 (canonicalize-command-name name2) command-table) name1)) (define (argument-template->parser template) ;; Deliberately handles only cases that occur in "commands.scm". (cond ((eq? 'tokens template) (lambda (port) (let loop ((tokens '())) (let ((token (read-token port))) (if (or (eof-object? token) (not token)) (list (reverse! tokens)) (loop (cons token tokens))))))) ((null? template) (lambda (port) '())) ((and (pair? template) (null? (cdr template)) (eq? 'object (car template))) (lambda (port) (list (read port)))) ((and (pair? template) (equal? ''optional (car template)) (pair? (cdr template)) (null? (cddr template))) (case (cadr template) ((token) (lambda (port) (let ((token (read-token port))) (if (or (eof-object? token) (not token)) (list #f) (list token))))) ((exact-integer) (lambda (port) (list (parse-optional-exact-integer port)))) ((exact-nonnegative-integer) (lambda (port) (list (parse-optional-exact-nonnegative-integer port)))) ((object) (lambda (port) (list (parse-optional-object port)))) (else (error "Malformed argument template: " template)))) (else (error "Malformed argument template: " template)))) (define (parse-optional-exact-integer port) (let ((object (parse-optional-object port))) (if (or (not object) (and (integer? object) (exact? object))) object (user-error "Argument not an exact integer: " object)))) (define (parse-optional-exact-nonnegative-integer port) (let ((object (parse-optional-object port))) (if (or (not object) (and (integer? object) (exact? object) (not (negative? object)))) object (user-error "Argument not an exact non-negative integer: " object)))) (define (parse-optional-object port) (let ((terminator (skip-whitespace port))) (if (or (eof-object? terminator) (eq? #\newline terminator)) #f (let ((object (read port))) (if (eof-object? object) #f object))))) ;;;; Command tables (define (lookup-command name) (let loop ((table command-table) (strings name)) (let ((value (command-table-value table (car strings)))) (cond ((or (not value) (null? (cdr strings))) value) ((command-table? value) (loop value (cdr strings))) (else #f))))) (define (command-table-value table string) (let ((entry (command-table-entry table string))) (and entry (caddr entry)))) (define (command-table-entry table string) (let loop ((entries (command-table-entries table))) (and (not (null? entries)) (let ((entry (car entries))) (if (and (<= (cadr entry) (string-length string) (string-length (car entry))) (= (string-length string) (match-strings (car entry) string))) entry (loop (cdr entries))))))) (define (match-strings s1 s2) (let ((n (min (string-length s1) (string-length s2)))) (let loop ((i 0)) (cond ((= i n) i) ((char=? (string-ref s1 i) (string-ref s2 i)) (loop (+ i 1))) (else i))))) (define (write-command-name name) (display (car name)) (for-each (lambda (string) (write-char #\space) (display string)) (cdr name))) (define (add-command name value table) (let loop ((strings name) (table table)) (let ((entry (or (let loop ((entries (command-table-entries table))) (and (not (null? entries)) (if (string=? (car strings) (caar entries)) (car entries) (loop (cdr entries))))) (let ((entry (list (car strings) #f #f))) (let ((entries (let ((entries (command-table-entries table))) (if (or (null? entries) (stringstring (reverse! chars)))))) (skip-whitespace port) (loop '()))) (define (skip-whitespace port) (let ((char (peek-char port))) (cond ((or (eof-object? char) (char=? #\newline char)) char) ((char-whitespace? char) (read-char port) (skip-whitespace port)) ((char=? #\# char) (read-char port) (skip-comment port)) (else char)))) (define (skip-comment port) (let ((char (peek-char port))) (if (or (eof-object? char) (char=? #\newline char)) char (begin (read-char port) (skip-comment port))))) (define (read-rest-of-line port) (let loop ((chars '())) (let ((char (read-char port))) (if (or (eof-object? char) (char=? #\newline char)) (list->string (reverse! chars)) (loop (cons char chars)))))) (define (discard-rest-of-line port) (let loop () (if (not (let ((char (read-char port))) (or (eof-object? char) (char=? #\newline char)))) (loop)))) ;;;; Commands (define command-table (make-command-table '())) (define-command "help" 'tokens (lambda (state tokens) "Type \"help\" followed by a command name for full documentation." (let loop ((name (if (null? tokens) '("help") tokens))) (let ((value (lookup-command name))) (cond ((not value) (write-command-name name) (display " is not a known command name.") (newline)) ((command? value) (display (command-documentation value)) (newline) (if (equal? '("help") (command-name value)) (begin (display "Available commands are:") (newline) (for-each (lambda (entry) (if (not (list? (caddr entry))) (begin (display " ") (display (car entry)) (newline)))) (command-table-entries command-table))))) ((command-table? value) (display "The \"") (write-command-name name) (display "\" command requires a subcommand.") (newline) (display "Available subcommands are:") (newline) (for-each (lambda (entry) (if (not (list? (caddr entry))) (begin (display " ") (write-command-name name) (write-char #\space) (display (car entry)) (newline)))) (command-table-entries value))) ((list? value) (loop value)) (else (error "Unknown value from lookup-command:" value))))) state)) (define-command "frame" '('optional exact-nonnegative-integer) frame) (define-command "position" '() position) (define-command "up" '('optional exact-integer) up) (define-command "down" '('optional exact-integer) down) (define-command "backtrace" '('optional exact-integer) backtrace) (define-command "evaluate" '(object) evaluate) (define-command '("info" "args") '() info-args) (define-command '("info" "frame") '() info-frame) (define-command "quit" '() (lambda (state) "Exit the debugger." (debugger-command-loop-quit))) (define-command-alias "f" "frame") (define-command-alias '("info" "f") '("info" "frame")) (define-command-alias "bt" "backtrace") (define-command-alias "where" "backtrace") (define-command-alias "p" "evaluate") (define-command-alias '("info" "stack") "backtrace") (define-command "continue" '() continue) (define-command "finish" '() finish) (define-command "trace-finish" '() trace-finish) (define-command "step" '('optional exact-integer) step) (define-command "next" '('optional exact-integer) next)