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Diffstat (limited to 'module/ice-9/debugger/command-loop.scm')
-rw-r--r-- | module/ice-9/debugger/command-loop.scm | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/module/ice-9/debugger/command-loop.scm b/module/ice-9/debugger/command-loop.scm new file mode 100644 index 000000000..62a08ea65 --- /dev/null +++ b/module/ice-9/debugger/command-loop.scm @@ -0,0 +1,542 @@ +;;;; Guile Debugger command loop + +;;; Copyright (C) 1999, 2001, 2002, 2003, 2006 Free Software Foundation, Inc. +;;; +;; This library is free software; you can redistribute it and/or +;; modify it under the terms of the GNU Lesser General Public +;; License as published by the Free Software Foundation; either +;; version 2.1 of the License, or (at your option) any later version. +;; +;; This library 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 +;; Lesser General Public License for more details. +;; +;; You should have received a copy of the GNU Lesser General Public +;; License along with this library; if not, write to the Free Software +;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +(define-module (ice-9 debugger command-loop) + #:use-module ((ice-9 debugger commands) :prefix debugger:) + #:export (debugger-command-loop + debugger-command-loop-error + debugger-command-loop-quit) + #:no-backtrace) + +;;; {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 set-readline-prompt! #f) + +(define (read-and-dispatch-command state port) + (if (using-readline?) + (begin + ;; Import set-readline-prompt! if we haven't already. + (or set-readline-prompt! + (set! set-readline-prompt! + (module-ref (resolve-module '(ice-9 readline)) + 'set-readline-prompt!))) + (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) + (string<? (car strings) (caar entries))) + (cons entry entries) + (begin + (let loop ((prev entries) (this (cdr entries))) + (if (or (null? this) + (string<? (car strings) (caar this))) + (set-cdr! prev (cons entry this)) + (loop this (cdr this)))) + entries))))) + (compute-string-abbreviations! entries) + (set-command-table-entries! table entries)) + entry)))) + (if (null? (cdr strings)) + (set-car! (cddr entry) value) + (loop (cdr strings) + (if (command-table? (caddr entry)) + (caddr entry) + (let ((table (make-command-table '()))) + (set-car! (cddr entry) table) + table))))))) + +(define (canonicalize-command-name name) + (cond ((and (string? name) + (not (string-null? name))) + (list name)) + ((let loop ((name name)) + (and (pair? name) + (string? (car name)) + (not (string-null? (car name))) + (or (null? (cdr name)) + (loop (cdr name))))) + name) + (else + (error "Illegal command name: " name)))) + +(define (compute-string-abbreviations! entries) + (let loop ((entries entries) (index 0)) + (let ((groups '())) + (for-each + (lambda (entry) + (let* ((char (string-ref (car entry) index)) + (group (assv char groups))) + (if group + (set-cdr! group (cons entry (cdr group))) + (set! groups + (cons (list char entry) + groups))))) + entries) + (for-each + (lambda (group) + (let ((index (+ index 1))) + (if (null? (cddr group)) + (set-car! (cdadr group) index) + (loop (let ((entry + (let loop ((entries (cdr group))) + (and (not (null? entries)) + (if (= index (string-length (caar entries))) + (car entries) + (loop (cdr entries))))))) + (if entry + (begin + (set-car! (cdr entry) index) + (delq entry (cdr group))) + (cdr group))) + index)))) + groups)))) + +;;;; Data structures + +(define command-table-rtd (make-record-type "command-table" '(entries))) +(define make-command-table (record-constructor command-table-rtd '(entries))) +(define command-table? (record-predicate command-table-rtd)) +(define command-table-entries (record-accessor command-table-rtd 'entries)) +(define set-command-table-entries! + (record-modifier command-table-rtd 'entries)) + +(define command-rtd + (make-record-type "command" + '(name parser documentation procedure))) + +(define make-command + (record-constructor command-rtd + '(name parser documentation procedure))) + +(define command? (record-predicate command-rtd)) +(define command-name (record-accessor command-rtd 'name)) +(define command-parser (record-accessor command-rtd 'parser)) +(define command-documentation (record-accessor command-rtd 'documentation)) +(define command-procedure (record-accessor command-rtd 'procedure)) + +;;;; Character parsing + +(define (read-token port) + (letrec + ((loop + (lambda (chars) + (let ((char (peek-char port))) + (cond ((eof-object? char) + (do-eof char chars)) + ((char=? #\newline char) + (do-eot chars)) + ((char-whitespace? char) + (do-eot chars)) + ((char=? #\# char) + (read-char port) + (let ((terminator (skip-comment port))) + (if (eof-object? char) + (do-eof char chars) + (do-eot chars)))) + (else + (read-char port) + (loop (cons char chars))))))) + (do-eof + (lambda (eof chars) + (if (null? chars) + eof + (do-eot chars)))) + (do-eot + (lambda (chars) + (if (null? chars) + #f + (list->string (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) debugger:frame) + +(define-command "position" '() debugger:position) + +(define-command "up" '('optional exact-integer) debugger:up) + +(define-command "down" '('optional exact-integer) debugger:down) + +(define-command "backtrace" '('optional exact-integer) debugger:backtrace) + +(define-command "evaluate" '(object) debugger:evaluate) + +(define-command '("info" "args") '() debugger:info-args) + +(define-command '("info" "frame") '() debugger: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") |