Megatest

;; WARNING: This proc operates assuming that it is in the directory above the
;;          logs directory you wish to log-rotate.
;;
(define (common:rotate-logs)
  (if (not (directory-exists? "logs"))(create-directory "logs"))
  (directory-fold 
   (lambda (file rem)
     (common:debug-handle-exceptions #t
      exn
      (debug:print-info 0 *default-log-port* "failed to rotate log " file ", probably handled by another process.")
      (let* ((fullname (conc "logs/" file))
             (file-age (- (current-seconds)(file-modification-time fullname))))
        (if (or (and (string-match "^.*.log" file)
                     (> (file-size fullname) 200000))
                (and (string-match "^server-.*.log" file)

			 "   expected: " (common:version-signature) "\n"
			 "   got:      " (common:get-last-run-version))
            (cond
             ((get-environment-variable "MT_SKIP_DB_MIGRATE") #t)
             ((and (file-exists? mtconf) (file-exists? dbfile) (not read-only)
                   (eq? (current-user-id)(file-owner mtconf))) ;; safe to run -cleanup-db
              (debug:print 0 *default-log-port* "   I see you are the owner of megatest.config, attempting to cleanup and reset to new version")
              (common:debug-handle-exceptions #t
               exn
               (begin
                 (debug:print 0 *default-log-port* "Failed to switch versions.")
                 (debug:print 0 *default-log-port* " message: " ((condition-property-accessor 'exn 'message) exn))
                 (print-call-chain (current-error-port))
                 (exit 1))
               (common:cleanup-db dbstruct)))

	  #t)
	#f)))

(define (common:get-megatest-exe)
  (or (getenv "MT_MEGATEST") "megatest"))

(define (common:read-encoded-string instr)
  (common:debug-handle-exceptions #t
   exn
   (common:debug-handle-exceptions #t
    exn
    (begin
      (debug:print-error 0 *default-log-port* "received bad encoded string \"" instr "\", message: " ((condition-property-accessor 'exn 'message) exn))
      (print-call-chain (current-error-port))
      #f)
    (read (open-input-string (base64:base64-decode instr))))
   (read (open-input-string (z3:decode-buffer (base64:base64-decode instr))))))

	      (if (null? tal)
		  #f
		  (loop (car tal)(cdr tal))))))))
  
(define (common:get-install-area)
  (let ((exe-path (car (argv))))
    (if (file-exists? exe-path)
	(common:debug-handle-exceptions #t
	 exn
	 #f
	 (pathname-directory
	  (pathname-directory 
	   (pathname-directory exe-path))))
	#f)))

;; return first path that can be created or already exists and is writable
;;
(define (common:get-create-writeable-dir dirs)
  (if (null? dirs)
      #f
      (let loop ((hed (car dirs))
		 (tal (cdr dirs)))
	(let ((res (or (and (directory? hed)
			    (file-write-access? hed)
			    hed)
		       (common:debug-handle-exceptions #t
			exn
			#f
			(create-directory hed #t)))))
	  (if (and (string? res)
		   (directory? res))
	      res
	      (if (null? tal)
		  #f
		  (loop (car tal)(cdr tal))))))))

;; return the youngest timestamp . filename
;;
(define (common:get-youngest glob-list)
  (let ((all-files (apply append
			  (map (lambda (patt)
				 (common:debug-handle-exceptions #t
				     exn
				     '()
				   (glob patt)))
			       glob-list))))
    (fold (lambda (fname res)
	    (let ((last-mod (car res))
		  (curmod   (common:debug-handle-exceptions #t
				exn
				0
			      (file-modification-time fname))))
	      (if (> curmod last-mod)
		  (list curmod fname)
		  res)))
	  '(0 "n/a")

				dir
				(conc (current-directory) "/" dir))))))

;; make "nice-path" available in config files and the repl
(define nice-path common:nice-path)

(define (common:read-link-f path)
  (common:debug-handle-exceptions #t
      exn
      (begin
	(debug:print-error 0 *default-log-port* "command \"/bin/readlink -f " path "\" failed.")
	path) ;; just give up
    (with-input-from-pipe
	(conc "/bin/readlink -f " path)
      (lambda ()