;; Copyright 2006-2014, Matthew Welland.
;;
;; This program is made available under the GNU GPL version 2.0 or
;; greater. See the accompanying file COPYING for details.
;;
;; This program is distributed WITHOUT ANY WARRANTY; without even the
;; implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
;; PURPOSE.
(require-extension (srfi 18) extras tcp s11n)
(use sqlite3 srfi-1 posix srfi-69 hostinfo dot-locking)
(import (prefix sqlite3 sqlite3:))
(declare (unit portlogger))
;; lsof -i
(define (portlogger:open-db fname)
(let* ((exists (file-exists? fname))
(db (sqlite3:open-database fname))
(handler (make-busy-timeout 136000))
(canwrite (file-write-access? fname)))
(sqlite3:set-busy-handler! db handler)
(sqlite3:execute db "PRAGMA synchronous = 0;")
(if (not exists)
(sqlite3:execute
db
"CREATE TABLE ports (
port INTEGER PRIMARY KEY,
state TEXT DEFAULT 'not-used',
fail_count INTEGER DEFAULT 0,
update_time TIMESTAMP DEFAULT (strftime('%s','now')) );"))
db))
(define (portlogger:open-run-close proc . params)
(let ((fname (conc "/tmp/." (current-user-name) "-portlogger.db")))
(handle-exceptions
exn
(begin
(release-dot-lock fname)
(debug:print 0 "ERROR: portlogger:open-run-close failed. " proc " " params)
(debug:print 0 " message: " ((condition-property-accessor 'exn 'message) exn))
(debug:print 0 "exn=" (condition->list exn))
(print-call-chain))
(let* ((lock (obtain-dot-lock fname 2 9 10))
(db (portlogger:open-db fname))
(res (apply proc db params)))
(sqlite3:finalize! db)
(release-dot-lock fname)
res))))
;; (fold-row PROC INIT DATABASE SQL . PARAMETERS)
(define (portlogger:take-port db portnum)
(let* ((qry1 (sqlite3:prepare db "INSERT INTO ports (port,state) VALUES (?,?);"))
(qry2 (sqlite3:prepare db "UPDATE ports SET state=?,update_time=strftime('%s','now') WHERE port=?;"))
(qry3 (sqlite3:prepare db "SELECT state FROM ports WHERE port=?;"))
(res (sqlite3:with-transaction
db
(lambda ()
;; (fold-row (lambda (var curr) (or var curr)) #f db "SELECT var FROM foo WHERE id=100;")
(let* ((curr #f)
(res #f))
(set! curr (sqlite3:fold-row
(lambda (var curr)
(or curr var curr))
"not-tried"
qry3
portnum))
;; (print "curr=" curr)
(set! res (case (string->symbol curr)
((released) (sqlite3:execute qry2 "taken" portnum) 'taken)
((not-tried) (sqlite3:execute qry1 portnum "taken") 'taken)
((taken) 'already-taken)
((failed) 'failed)
(else 'error)))
;; (print "res=" res)
res)))))
(sqlite3:finalize! qry1)
(sqlite3:finalize! qry2)
(sqlite3:finalize! qry3)
res))
(define (portlogger:get-prev-used-port db)
(sqlite3:fold-row
(lambda (var curr)
(or curr var curr))
#f
db
"SELECT (port) FROM ports WHERE state='released' LIMIT 1;"))
(define (portlogger:find-port db)
(let ((portnum (or (portlogger:get-prev-used-port db)
(+ 50000 ;; top of registered ports
(random (- 60000 50000))))))
(portlogger:take-port db portnum)
portnum))
;; set port to "released", "failed" etc.
;;
(define (portlogger:set-port db portnum value)
(sqlite3:execute db "UPDATE ports SET state=?,update_time=strftime('%s','now') WHERE port=?;" value portnum))
;; set port to failed (attempted to take but got error)
;;
(define (portlogger:set-failed db portnum)
(sqlite3:execute db "UPDATE ports SET state='failed',fail_count=fail_count+1,update_time=strftime('%s','now') WHERE port=?;" portnum))
;;======================================================================
;; MAIN
;;======================================================================
(define (portlogger:main . args)
(let* ((db (portlogger:open-db (conc "/tmp/." (current-user-name) "-portlogger.db")))
(numargs (length args))
(result (cond
((> numargs 1) ;; most commands
(case (string->symbol (car args)) ;; commands with two or more params
((take)(portlogger:take-port db (string->number (cadr args))))
((set) (portlogger:set-port db
(string->number (cadr args))
(caddr args))
(caddr args))
((failed)(portlogger:set-failed db (string->number (cadr args))) 'failed))))))
(sqlite3:finalize! db)
result))
;; (print (apply portlogger:main (cdr (argv))))