362 lines
13 KiB
Scheme
362 lines
13 KiB
Scheme
;;; GNU Guix --- Functional package management for GNU
|
|
;;; Copyright © 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
|
|
;;; Copyright © 2018 Chris Marusich <cmmarusich@gmail.com>
|
|
;;;
|
|
;;; This file is part of GNU Guix.
|
|
;;;
|
|
;;; GNU Guix 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 3 of the License, or (at
|
|
;;; your option) any later version.
|
|
;;;
|
|
;;; GNU Guix 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 GNU Guix. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
(define-module (gnu build marionette)
|
|
#:use-module (srfi srfi-9)
|
|
#:use-module (srfi srfi-26)
|
|
#:use-module (rnrs io ports)
|
|
#:use-module (ice-9 match)
|
|
#:use-module (ice-9 popen)
|
|
#:export (marionette?
|
|
make-marionette
|
|
marionette-eval
|
|
wait-for-file
|
|
wait-for-tcp-port
|
|
wait-for-unix-socket
|
|
marionette-control
|
|
marionette-screen-text
|
|
wait-for-screen-text
|
|
%qwerty-us-keystrokes
|
|
marionette-type))
|
|
|
|
;;; Commentary:
|
|
;;;
|
|
;;; Instrumentation tools for QEMU virtual machines (VMs). A "marionette" is
|
|
;;; essentially a VM (a QEMU instance) with its monitor connected to a
|
|
;;; Unix-domain socket, and with a REPL inside the guest listening on a
|
|
;;; virtual console, which is itself connected to the host via a Unix-domain
|
|
;;; socket--these are the marionette's strings, connecting it to the almighty
|
|
;;; puppeteer.
|
|
;;;
|
|
;;; Code:
|
|
|
|
(define-record-type <marionette>
|
|
(marionette command pid monitor repl)
|
|
marionette?
|
|
(command marionette-command) ;list of strings
|
|
(pid marionette-pid) ;integer
|
|
(monitor marionette-monitor) ;port
|
|
(repl %marionette-repl)) ;promise of a port
|
|
|
|
(define-syntax-rule (marionette-repl marionette)
|
|
(force (%marionette-repl marionette)))
|
|
|
|
(define* (wait-for-monitor-prompt port #:key (quiet? #t))
|
|
"Read from PORT until we have seen all of QEMU's monitor prompt. When
|
|
QUIET? is false, the monitor's output is written to the current output port."
|
|
(define full-prompt
|
|
(string->list "(qemu) "))
|
|
|
|
(let loop ((prompt full-prompt)
|
|
(matches '())
|
|
(prefix '()))
|
|
(match prompt
|
|
(()
|
|
;; It's useful to set QUIET? so we don't display the echo of our own
|
|
;; commands.
|
|
(unless quiet?
|
|
(for-each (lambda (line)
|
|
(format #t "qemu monitor: ~a~%" line))
|
|
(string-tokenize (list->string (reverse prefix))
|
|
(char-set-complement (char-set #\newline))))))
|
|
((chr rest ...)
|
|
(let ((read (read-char port)))
|
|
(cond ((eqv? read chr)
|
|
(loop rest (cons read matches) prefix))
|
|
((eof-object? read)
|
|
(error "EOF while waiting for QEMU monitor prompt"
|
|
(list->string (reverse prefix))))
|
|
(else
|
|
(loop full-prompt
|
|
'()
|
|
(cons read (append matches prefix))))))))))
|
|
|
|
(define* (make-marionette command
|
|
#:key (socket-directory "/tmp") (timeout 20))
|
|
"Return a QEMU marionette--i.e., a virtual machine with open connections to the
|
|
QEMU monitor and to the guest's backdoor REPL."
|
|
(define (file->sockaddr file)
|
|
(make-socket-address AF_UNIX
|
|
(string-append socket-directory "/" file)))
|
|
|
|
(define extra-options
|
|
(list "-nographic"
|
|
"-monitor" (string-append "unix:" socket-directory "/monitor")
|
|
"-chardev" (string-append "socket,id=repl,path=" socket-directory
|
|
"/repl")
|
|
|
|
;; See
|
|
;; <http://www.linux-kvm.org/page/VMchannel_Requirements#Invocation>.
|
|
"-device" "virtio-serial"
|
|
"-device" "virtserialport,chardev=repl,name=org.gnu.guix.port.0"))
|
|
|
|
(define (accept* port)
|
|
(match (select (list port) '() (list port) timeout)
|
|
(((port) () ())
|
|
(accept port))
|
|
(_
|
|
(error "timeout in 'accept'" port))))
|
|
|
|
(let ((monitor (socket AF_UNIX SOCK_STREAM 0))
|
|
(repl (socket AF_UNIX SOCK_STREAM 0)))
|
|
(bind monitor (file->sockaddr "monitor"))
|
|
(listen monitor 1)
|
|
(bind repl (file->sockaddr "repl"))
|
|
(listen repl 1)
|
|
|
|
(match (primitive-fork)
|
|
(0
|
|
(catch #t
|
|
(lambda ()
|
|
(close monitor)
|
|
(close repl)
|
|
(match command
|
|
((program . args)
|
|
(apply execl program program
|
|
(append args extra-options)))))
|
|
(lambda (key . args)
|
|
(print-exception (current-error-port)
|
|
(stack-ref (make-stack #t) 1)
|
|
key args)
|
|
(primitive-exit 1))))
|
|
(pid
|
|
(format #t "QEMU runs as PID ~a~%" pid)
|
|
|
|
(match (accept* monitor)
|
|
((monitor-conn . _)
|
|
(display "connected to QEMU's monitor\n")
|
|
(close-port monitor)
|
|
(wait-for-monitor-prompt monitor-conn)
|
|
(display "read QEMU monitor prompt\n")
|
|
|
|
(marionette (append command extra-options) pid
|
|
monitor-conn
|
|
|
|
;; The following 'accept' call connects immediately, but
|
|
;; we don't know whether the guest has connected until
|
|
;; we actually receive the 'ready' message.
|
|
(match (accept* repl)
|
|
((repl-conn . addr)
|
|
(display "connected to guest REPL\n")
|
|
(close-port repl)
|
|
;; Delay reception of the 'ready' message so that the
|
|
;; caller can already send monitor commands.
|
|
(delay
|
|
(match (read repl-conn)
|
|
('ready
|
|
(display "marionette is ready\n")
|
|
repl-conn))))))))))))
|
|
|
|
(define (marionette-eval exp marionette)
|
|
"Evaluate EXP in MARIONETTE's backdoor REPL. Return the result."
|
|
(match marionette
|
|
(($ <marionette> command pid monitor (= force repl))
|
|
(write exp repl)
|
|
(newline repl)
|
|
(read repl))))
|
|
|
|
(define* (wait-for-file file marionette
|
|
#:key (timeout 10) (read 'read))
|
|
"Wait until FILE exists in MARIONETTE; READ its content and return it. If
|
|
FILE has not shown up after TIMEOUT seconds, raise an error."
|
|
(match (marionette-eval
|
|
`(let loop ((i ,timeout))
|
|
(cond ((file-exists? ,file)
|
|
(cons 'success (call-with-input-file ,file ,read)))
|
|
((> i 0)
|
|
(sleep 1)
|
|
(loop (- i 1)))
|
|
(else
|
|
'failure)))
|
|
marionette)
|
|
(('success . result)
|
|
result)
|
|
('failure
|
|
(error "file didn't show up" file))))
|
|
|
|
(define* (wait-for-tcp-port port marionette
|
|
#:key (timeout 20))
|
|
"Wait for up to TIMEOUT seconds for PORT to accept connections in
|
|
MARIONETTE. Raise an error on failure."
|
|
;; Note: The 'connect' loop has to run within the guest because, when we
|
|
;; forward ports to the host, connecting to the host never raises
|
|
;; ECONNREFUSED.
|
|
(match (marionette-eval
|
|
`(begin
|
|
(let ((sock (socket PF_INET SOCK_STREAM 0)))
|
|
(let loop ((i 0))
|
|
(catch 'system-error
|
|
(lambda ()
|
|
(connect sock AF_INET INADDR_LOOPBACK ,port)
|
|
(close-port sock)
|
|
'success)
|
|
(lambda args
|
|
(if (< i ,timeout)
|
|
(begin
|
|
(sleep 1)
|
|
(loop (+ 1 i)))
|
|
'failure))))))
|
|
marionette)
|
|
('success #t)
|
|
('failure
|
|
(error "nobody's listening on port" port))))
|
|
|
|
(define* (wait-for-unix-socket file-name marionette
|
|
#:key (timeout 20))
|
|
"Wait for up to TIMEOUT seconds for FILE-NAME, a Unix domain socket, to
|
|
accept connections in MARIONETTE. Raise an error on failure."
|
|
(match (marionette-eval
|
|
`(begin
|
|
(let ((sock (socket PF_UNIX SOCK_STREAM 0)))
|
|
(let loop ((i 0))
|
|
(catch 'system-error
|
|
(lambda ()
|
|
(connect sock AF_UNIX ,file-name)
|
|
(close-port sock)
|
|
'success)
|
|
(lambda args
|
|
(if (< i ,timeout)
|
|
(begin
|
|
(sleep 1)
|
|
(loop (+ 1 i)))
|
|
'failure))))))
|
|
marionette)
|
|
('success #t)
|
|
('failure
|
|
(error "nobody's listening on unix domain socket" file-name))))
|
|
|
|
(define (marionette-control command marionette)
|
|
"Run COMMAND in the QEMU monitor of MARIONETTE. COMMAND is a string such as
|
|
\"sendkey ctrl-alt-f1\" or \"screendump foo.ppm\" (info \"(qemu-doc)
|
|
pcsys_monitor\")."
|
|
(match marionette
|
|
(($ <marionette> _ _ monitor)
|
|
(display command monitor)
|
|
(newline monitor)
|
|
;; The "quit" command terminates QEMU immediately, with no output.
|
|
(unless (string=? command "quit") (wait-for-monitor-prompt monitor)))))
|
|
|
|
(define* (marionette-screen-text marionette
|
|
#:key
|
|
(ocrad "ocrad"))
|
|
"Take a screenshot of MARIONETTE, perform optical character
|
|
recognition (OCR), and return the text read from the screen as a string. Do
|
|
this by invoking OCRAD (file name for GNU Ocrad's command)"
|
|
(define (random-file-name)
|
|
(string-append "/tmp/marionette-screenshot-"
|
|
(number->string (random (expt 2 32)) 16)
|
|
".ppm"))
|
|
|
|
(let ((image (random-file-name)))
|
|
(dynamic-wind
|
|
(const #t)
|
|
(lambda ()
|
|
(marionette-control (string-append "screendump " image)
|
|
marionette)
|
|
|
|
;; Tell Ocrad to invert the image colors (make it black on white) and
|
|
;; to scale the image up, which significantly improves the quality of
|
|
;; the result. In spite of this, be aware that OCR confuses "y" and
|
|
;; "V" and sometimes erroneously introduces white space.
|
|
(let* ((pipe (open-pipe* OPEN_READ ocrad
|
|
"-i" "-s" "10" image))
|
|
(text (get-string-all pipe)))
|
|
(unless (zero? (close-pipe pipe))
|
|
(error "'ocrad' failed" ocrad))
|
|
text))
|
|
(lambda ()
|
|
(false-if-exception (delete-file image))))))
|
|
|
|
(define* (wait-for-screen-text marionette predicate
|
|
#:key (timeout 30) (ocrad "ocrad"))
|
|
"Wait for TIMEOUT seconds or until the screen text on MARIONETTE matches
|
|
PREDICATE, whichever comes first. Raise an error when TIMEOUT is exceeded."
|
|
(define start
|
|
(car (gettimeofday)))
|
|
|
|
(define end
|
|
(+ start timeout))
|
|
|
|
(let loop ()
|
|
(if (> (car (gettimeofday)) end)
|
|
(error "'wait-for-screen-text' timeout" predicate)
|
|
(or (predicate (marionette-screen-text marionette #:ocrad ocrad))
|
|
(begin
|
|
(sleep 1)
|
|
(loop))))))
|
|
|
|
(define %qwerty-us-keystrokes
|
|
;; Maps "special" characters to their keystrokes.
|
|
'((#\newline . "ret")
|
|
(#\space . "spc")
|
|
(#\- . "minus")
|
|
(#\+ . "shift-equal")
|
|
(#\* . "shift-8")
|
|
(#\= . "equal")
|
|
(#\? . "shift-slash")
|
|
(#\[ . "bracket_left")
|
|
(#\] . "bracket_right")
|
|
(#\{ . "shift-bracket_left")
|
|
(#\} . "shift-bracket_right")
|
|
(#\( . "shift-9")
|
|
(#\) . "shift-0")
|
|
(#\/ . "slash")
|
|
(#\< . "shift-comma")
|
|
(#\> . "shift-dot")
|
|
(#\. . "dot")
|
|
(#\, . "comma")
|
|
(#\; . "semicolon")
|
|
(#\' . "apostrophe")
|
|
(#\" . "shift-apostrophe")
|
|
(#\` . "grave_accent")
|
|
(#\bs . "backspace")
|
|
(#\tab . "tab")))
|
|
|
|
(define (character->keystroke chr keystrokes)
|
|
"Return the keystroke for CHR according to the keyboard layout defined by
|
|
KEYSTROKES."
|
|
(if (char-set-contains? char-set:upper-case chr)
|
|
(string-append "shift-" (string (char-downcase chr)))
|
|
(or (assoc-ref keystrokes chr)
|
|
(string chr))))
|
|
|
|
(define* (string->keystroke-commands str
|
|
#:optional
|
|
(keystrokes
|
|
%qwerty-us-keystrokes))
|
|
"Return a list of QEMU monitor commands to send the keystrokes corresponding
|
|
to STR. KEYSTROKES is an alist specifying a mapping from characters to
|
|
keystrokes."
|
|
(string-fold-right (lambda (chr result)
|
|
(cons (string-append
|
|
"sendkey "
|
|
(character->keystroke chr keystrokes))
|
|
result))
|
|
'()
|
|
str))
|
|
|
|
(define* (marionette-type str marionette
|
|
#:key (keystrokes %qwerty-us-keystrokes))
|
|
"Type STR on MARIONETTE's keyboard, using the KEYSTROKES alist to map characters
|
|
to actual keystrokes."
|
|
(for-each (cut marionette-control <> marionette)
|
|
(string->keystroke-commands str keystrokes)))
|
|
|
|
;;; marionette.scm ends here
|