;;======================================================================
;; Copyright 2017, Matthew Welland.
;;
;; This file is part of Megatest.
;;
;; Megatest 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.
;;
;; Megatest 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 Megatest. If not, see <http://www.gnu.org/licenses/>.
;;======================================================================
(declare (unit commonmod))
(declare (uses mtver))
(module commonmod
*
(import scheme
chicken.base
chicken.condition
chicken.file
chicken.time
chicken.file.posix
chicken.process-context.posix
chicken.io
chicken.string
(prefix sqlite3 sqlite3:)
system-information
typed-records
md5
message-digest
regex
srfi-1
srfi-18
srfi-69
mtver
)
;;======================================================================
;; CONTENTS
;;
;; config file utils
;; misc conversion, data manipulation functions
;; testsuite and area utilites
;;
;;======================================================================
(include "megatest-fossil-hash.scm")
;; dot-locking egg seems not to work, using this for now
;; if lock is older than expire-time then remove it and try again
;; to get the lock
;;
(define (common:simple-file-lock fname #!key (expire-time 300))
(let ((fmod-time (handle-exceptions
ext
(current-seconds)
(file-modification-time fname))))
(if (file-exists? fname)
(if (> (- (current-seconds) fmod-time) expire-time)
(begin
(handle-exceptions exn #f (delete-file* fname))
(common:simple-file-lock fname expire-time: expire-time))
#f)
(let ((key-string (conc (get-host-name) "-" (current-process-id))))
(with-output-to-file fname
(lambda ()
(print key-string)))
(thread-sleep! 0.251)
(if (file-exists? fname)
(handle-exceptions exn
#f
(with-input-from-file fname
(lambda ()
(equal? key-string (read-line)))))
#f)))))
(define (common:simple-file-lock-and-wait fname #!key (expire-time 300))
(let ((end-time (+ expire-time (current-seconds))))
(let loop ((got-lock (common:simple-file-lock fname expire-time: expire-time)))
(if got-lock
#t
(if (> end-time (current-seconds))
(begin
(thread-sleep! 3)
(loop (common:simple-file-lock fname expire-time: expire-time)))
#f)))))
(define (common:simple-file-release-lock fname)
(handle-exceptions
exn
#f ;; I don't really care why this failed (at least for now)
(delete-file* fname)))
)