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(sqlite3:set-busy-handler! db (sqlite3:make-busy-timeout 30000))
(if sync-mode
(sqlite3:execute db (conc "PRAGMA synchronous = "sync-mode";")))
(if journal-mode
(sqlite3:execute db (conc "PRAGMA journal_mode = "journal-mode";")))
(if (and init-proc (not db-exists))
(init-proc db))
db)))
db))
expire-time: 30)
(begin
(if (file-exists? fname )
(let ((db (sqlite3:open-database fname)))
;; pragmas synchronous not needed because this db is used read-only
;; (sqlite3:execute db (conc "PRAGMA synchronous = "mode";")
(sqlite3:set-busy-handler! db (sqlite3:make-busy-timeout 30000)) ;; read-only but still need timeout
db )
(print "file doesn't exist: " fname))))
(print "cautious-open-database: file doesn't exist: " fname))))
(exn (io-error)
(dbfile:print-err exn "ERROR: i/o error with " fname ". Check permissions, disk space etc. and try again.")
(retry))
(exn (corrupt)
(dbfile:print-err exn "ERROR: database " fname " is corrupt. Repair it to proceed.")
(retry))
(exn (busy)
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(thread-sleep! 0.25)
(if (file-exists? fname)
(handle-exceptions exn
#f
(with-input-from-file fname
(lambda ()
(equal? key-string (read-line)))))
(begin
(dbfile:print-err "dbfile:simple-file-lock created " fname " but it was gone 0.25 seconds later")
#f)
#f
)
)
)
)
)
)
(define (dbfile:simple-file-lock-and-wait fname #!key (expire-time 300))
(let ((end-time (+ expire-time (current-seconds))))
|