;ò ¢)?Bc@spdZdkZdkZdkZdkZdkZdkZdklZl Z dZ dZ ye e fWnej odZ dZ nXead„Zdefd „ƒYZd efd „ƒYZd efd „ƒYZdefd„ƒYZdfd„ƒYZd„Zd„Zd„Zd„Zd„Zedjo-dkZdkZeeei dƒƒndS(sIPortable, NFS-safe file locking with timeouts. This code implements an NFS-safe file-based locking algorithm influenced by the GNU/Linux open(2) manpage, under the description of the O_EXCL option. From RH6.1: [...] O_EXCL is broken on NFS file systems, programs which rely on it for performing locking tasks will contain a race condition. The solution for performing atomic file locking using a lockfile is to create a unique file on the same fs (e.g., incorporating hostname and pid), use link(2) to make a link to the lockfile. If link() returns 0, the lock is successful. Otherwise, use stat(2) on the unique file to check if its link count has increased to 2, in which case the lock is also successful. The assumption made here is that there will be no `outside interference', e.g. no agent external to this code will have access to link() to the affected lock files. LockFile objects support lock-breaking so that you can't wedge a process forever. This is especially helpful in a web environment, but may not be appropriate for all applications. Locks have a `lifetime', which is the maximum length of time the process expects to retain the lock. It is important to pick a good number here because other processes will not break an existing lock until the expected lifetime has expired. Too long and other processes will hang; too short and you'll end up trampling on existing process locks -- and possibly corrupting data. In a distributed (NFS) environment, you also need to make sure that your clocks are properly synchronized. Locks can also log their state to a log file. When running under Mailman, the log file is placed in a Mailman-specific location, otherwise, the log file is called `LockFile.log' and placed in the temp directory (calculated from tempfile.mktemp()). N(sST_NLINKsST_MTIMEii iicCs¥ttjoydkl}|dƒaWqtj o`dk}tii|i ƒƒd}tii |dƒ}dfd„ƒY}||ƒaqXntSdS(N(s StampedLoggerslocksis LockFile.logsSimpleUserFilecBstZd„Zd„ZRS(NcCs,t|ddƒ|_dtiƒ|_dS(Nsais(%d) (sopenspathsselfs_SimpleUserFile__fpsossgetpids_SimpleUserFile__prefix(sselfspath((s /var/mailman/Mailman/LockFile.pys__init__cscCs3dtiƒ}|ii|i|d|ƒdS(Ns%.3fs (stimesnowsselfs_SimpleUserFile__fpswrites_SimpleUserFile__prefixsmsg(sselfsmsgsnow((s /var/mailman/Mailman/LockFile.pyswritefs(s__name__s __module__s__init__swrite(((s /var/mailman/Mailman/LockFile.pysSimpleUserFilebs ( s_logfilesNonesMailman.Logging.StampedLoggers StampedLoggers ImportErrorstempfilesosspathssplitsmktempsdirsjoinsSimpleUserFile(s StampedLoggersSimpleUserFilestempfilespathsdir((s /var/mailman/Mailman/LockFile.pys _get_logfileVs   s LockErrorcBstZdZRS(s-Base class for all exceptions in this module.(s__name__s __module__s__doc__(((s /var/mailman/Mailman/LockFile.pys LockErroros sAlreadyLockedErrorcBstZdZRS(s4An attempt is made to lock an already locked object.(s__name__s __module__s__doc__(((s /var/mailman/Mailman/LockFile.pysAlreadyLockedErrorrs sNotLockedErrorcBstZdZRS(s9An attempt is made to unlock an object that isn't locked.(s__name__s __module__s__doc__(((s /var/mailman/Mailman/LockFile.pysNotLockedErrorus s TimeOutErrorcBstZdZRS(s7The timeout interval elapsed before the lock succeeded.(s__name__s __module__s__doc__(((s /var/mailman/Mailman/LockFile.pys TimeOutErrorxs sLockFilecBsétZdZdZeed„Zd„Zd„Zd„Z e ed„Z dd„Z ed„Z d „Zd „Zd „Zd „Zd „Zd„Zdd„Zd„Zd„Ze d„Zd„Zd„Zd„Zd„ZRS(s'A portable way to lock resources by way of the file system. This class supports the following methods: __init__(lockfile[, lifetime[, withlogging]]): Create the resource lock using lockfile as the global lock file. Each process laying claim to this resource lock will create their own temporary lock files based on the path specified by lockfile. Optional lifetime is the number of seconds the process expects to hold the lock. Optional withlogging, when true, turns on lockfile logging (see the module docstring for details). set_lifetime(lifetime): Set a new lock lifetime. This takes affect the next time the file is locked, but does not refresh a locked file. get_lifetime(): Return the lock's lifetime. refresh([newlifetime[, unconditionally]]): Refreshes the lifetime of a locked file. Use this if you realize that you need to keep a resource locked longer than you thought. With optional newlifetime, set the lock's lifetime. Raises NotLockedError if the lock is not set, unless optional unconditionally flag is set to true. lock([timeout]): Acquire the lock. This blocks until the lock is acquired unless optional timeout is greater than 0, in which case, a TimeOutError is raised when timeout number of seconds (or possibly more) expires without lock acquisition. Raises AlreadyLockedError if the lock is already set. unlock([unconditionally]): Relinquishes the lock. Raises a NotLockedError if the lock is not set, unless optional unconditionally is true. locked(): Return true if the lock is set, otherwise false. To avoid race conditions, this refreshes the lock (on set locks). icCs‡||_||_ti|_tid7_d|ti ƒt i ƒ|if|_ ||_t ii|iƒd|_t|_dS(s¬Create the resource lock using lockfile as the global lock file. Each process laying claim to this resource lock will create their own temporary lock files based on the path specified by lockfile. Optional lifetime is the number of seconds the process expects to hold the lock. Optional withlogging, when true, turns on lockfile logging (see the module docstring for details). is %s.%s.%d.%dN(slockfilesselfs_LockFile__lockfileslifetimes_LockFile__lifetimesLockFilesCOUNTERs_LockFile__counterssockets gethostnamesossgetpids_LockFile__tmpfnames withloggings_LockFile__withloggingspathssplits_LockFile__logprefixsTrues_LockFile__owned(sselfslockfileslifetimes withlogging((s /var/mailman/Mailman/LockFile.pys__init__¯s    ( cCsAdt|ƒ|i|iƒodpd|itiƒfSdS(Ns$slockedsunlocked(sidsselfs_LockFile__lockfileslockeds_LockFile__lifetimesossgetpid(sself((s /var/mailman/Mailman/LockFile.pys__repr__ÇscCs ||_dS(sŠSet a new lock lifetime. This takes affect the next time the file is locked, but does not refresh a locked file. N(slifetimesselfs_LockFile__lifetime(sselfslifetime((s /var/mailman/Mailman/LockFile.pys set_lifetimeÍscCs |iSdS(sReturn the lock's lifetime.N(sselfs_LockFile__lifetime(sself((s /var/mailman/Mailman/LockFile.pys get_lifetimeÕscCs[|tj o|i|ƒn|iƒ o| o#tdt|ƒ|iƒf‚ndS(sCRefreshes the lifetime of a locked file. Use this if you realize that you need to keep a resource locked longer than you thought. With optional newlifetime, set the lock's lifetime. Raises NotLockedError if the lock is not set, unless optional unconditionally flag is set to true. s%s: %sN( s newlifetimesNonesselfs set_lifetimeslockedsunconditionallysNotLockedErrorsreprs_LockFile__read(sselfs newlifetimesunconditionally((s /var/mailman/Mailman/LockFile.pysrefreshÙs  cCs|otiƒ|}n|iƒ|iƒ|idƒd}x¿to·|d7}y2t i |i |i ƒ|idƒ|iƒPWnÎt j oÂ}|itijoqY|itijo.|id|dtƒt i|i ƒ‚qY|iƒdjo!|id|iƒdtƒqY|iƒ|i jo|id ƒt‚qYnX|o|tiƒjo't i|i ƒ|id ƒt‚ntiƒ|iƒtjo!|iƒ|id dtƒn|d  o|id ƒn|iƒqEWdS(s?Acquire the lock. This blocks until the lock is acquired unless optional timeout is greater than 0, in which case, a TimeOutError is raised when timeout number of seconds (or possibly more) expires without lock acquisition. Raises AlreadyLockedError if the lock is already set. s laying claimiÿÿÿÿis got the locksunexpected link error: %ss importantisunexpected linkcount: %dsalready lockeds timed outslifetime has expired, breakingidswaiting for claimN(stimeoutstimes timeout_timesselfs_LockFile__writes_LockFile__touchs_LockFile__writelogs loopcountsTruesosslinks_LockFile__tmpfnames_LockFile__lockfilesOSErrorseserrnosENOENTsEEXISTsunlinks_LockFile__linkcounts_LockFile__readsAlreadyLockedErrors TimeOutErrors_LockFile__releasetimes CLOCK_SLOPs_LockFile__breaks_LockFile__sleep(sselfstimeoutses loopcounts timeout_time((s /var/mailman/Mailman/LockFile.pyslockçsR               cCsÎ|iƒ}| o| o t‚n|oJyti|iƒWqwtj o#}|i t i jo‚qsqwXnyti|i ƒWn/tj o#}|i t i jo‚q½nX|i dƒdS(sõUnlock the lock. If we don't already own the lock (either because of unbalanced unlock calls, or because the lock was stolen out from under us), raise a NotLockedError, unless optional `unconditionally' is true. sunlockedN(sselfslockedsislockedsunconditionallysNotLockedErrorsossunlinks_LockFile__lockfilesOSErrorseserrnosENOENTs_LockFile__tmpfnames_LockFile__writelog(sselfsunconditionallysesislocked((s /var/mailman/Mailman/LockFile.pysunlock:s    cCsvy|iƒWn3tj o'}|itijotSqD‚nX|iƒdjotSn|iƒ|i jSdS(sÈReturn true if we own the lock, false if we do not. Checking the status of the lock resets the lock's lifetime, which helps avoid race conditions during the lock status test. iN( sselfs_LockFile__touchsOSErrorseserrnosEPERMsFalses_LockFile__linkcounts_LockFile__reads_LockFile__tmpfname(sselfse((s /var/mailman/Mailman/LockFile.pyslockedQscCs|idtƒdS(Nsunconditionally(sselfsunlocksTrue(sself((s /var/mailman/Mailman/LockFile.pysfinalizefscCs|io|iƒndS(N(sselfs_LockFile__ownedsfinalize(sself((s /var/mailman/Mailman/LockFile.pys__del__is cCs||iƒ|iƒ}d|itiƒ|f|_t i |i|iƒ|i ƒt |_ t i|ƒ|idƒdS(Ns%s.%s.%dstransferred the lock(sselfs_LockFile__touchs_LockFile__readswinners_LockFile__lockfilessockets gethostnamespids_LockFile__tmpfnamesosslinks_LockFile__writesFalses_LockFile__ownedsunlinks_LockFile__writelog(sselfspidswinner((s /var/mailman/Mailman/LockFile.pys _transfer_tots     cCsud|itiƒtiƒf|_}x8|iƒdjp|i ƒ|jot i dƒq,W|i dƒdS(Ns%s.%s.%dif0.25stook possession of the lock( sselfs_LockFile__lockfilessockets gethostnamesossgetpids_LockFile__tmpfnamestmpfnames_LockFile__linkcounts_LockFile__readstimessleeps_LockFile__writelog(sselfstmpfname((s /var/mailman/Mailman/LockFile.pys_take_possessionŒs )&cCs t|_dS(N(sFalsesselfs_LockFile__owned(sself((s /var/mailman/Mailman/LockFile.pys_disown•scCsL|ip|o7tƒ}|id|i|fƒti d|ƒndS(Ns%s %s sfile( sselfs_LockFile__withloggings importants _get_logfileslogfswrites_LockFile__logprefixsmsgs tracebacks print_stack(sselfsmsgs importantslogf((s /var/mailman/Mailman/LockFile.pys __writelogœs cCsTtidƒ}z0t|idƒ}|i|iƒ|iƒWdti|ƒXdS(Nisw( sossumasksoldmasksopensselfs_LockFile__tmpfnamesfpswritesclose(sselfsfpsoldmask((s /var/mailman/Mailman/LockFile.pys__write¢scCsgy-t|iƒ}|iƒ}|iƒ|SWn3tj o'}|i t i jo‚nt SnXdS(N( sopensselfs_LockFile__lockfilesfpsreadsfilenamesclosesEnvironmentErrorseserrnosENOENTsNone(sselfsfpsesfilename((s /var/mailman/Mailman/LockFile.pys__read¬s  cCsmtiƒ|i}y$ti|p|i||fƒWn/tj o#}|i t i jo‚qinXdS(N( stimesselfs_LockFile__lifetimestsossutimesfilenames_LockFile__tmpfnamesOSErrorseserrnosENOENT(sselfsfilenamesest((s /var/mailman/Mailman/LockFile.pys__touch¶s $cCsRyti|iƒtSWn3tj o'}|itijo‚ndSnXdS(Niÿÿÿÿ( sossstatsselfs_LockFile__lockfilesST_MTIMEsOSErrorseserrnosENOENT(sselfse((s /var/mailman/Mailman/LockFile.pys __releasetime¾s cCsRyti|iƒtSWn3tj o'}|itijo‚ndSnXdS(Niÿÿÿÿ( sossstatsselfs_LockFile__lockfilesST_NLINKsOSErrorseserrnosENOENT(sselfse((s /var/mailman/Mailman/LockFile.pys __linkcountÅs cCsêy|i|iƒWn/tj o#}|itijo‚qFnX|iƒ}yt i |iƒWn/tj o#}|iti jo‚q˜nXy|ot i |ƒnWn/tj o#}|iti jo‚qænXdS(N( sselfs_LockFile__touchs_LockFile__lockfilesOSErrorseserrnosEPERMs_LockFile__readswinnersossunlinksENOENT(sselfseswinner((s /var/mailman/Mailman/LockFile.pys__breakÌs"    cCs%tiƒdd}ti|ƒdS(Nf2.0f0.01(srandomsintervalstimessleep(sselfsinterval((s /var/mailman/Mailman/LockFile.pys__sleepîs(s__name__s __module__s__doc__sCOUNTERsDEFAULT_LOCK_LIFETIMEsFalses__init__s__repr__s set_lifetimes get_lifetimesNonesrefreshslocksunlockslockedsfinalizes__del__s _transfer_tos_take_possessions_disowns_LockFile__writelogs_LockFile__writes_LockFile__reads_LockFile__touchs_LockFile__releasetimes_LockFile__linkcounts_LockFile__breaks_LockFile__sleep(((s /var/mailman/Mailman/LockFile.pysLockFile}s. *    S          "cCskdtiƒ}tddtddƒ}dtiƒ}dtiƒ}|GdG|GHt }d }d }d }zƒy2tiƒ}|Gd GH|iƒ|Gd GHt}Wntj o|Gd GHn0Xtiƒ}|Gd G||GdGHti|ƒWd|oRy/|iƒtiƒ}|GdG||GdGHWqLtj o|GdGHqLXnX|GdG|GHti|ƒdS(Ns[%d]s /tmp/LockTests withloggingslifetimeixiis workinterval:is acquiring...s acquired...s timed outsacquisition time:ssecondsslock hold time:slock was brokens webhit sleep:(sossgetpidsprefixsLockFilesTrueslockfilesrandoms workintervalshitwaitsFalsesislockedst0st1st2stimeslocks TimeOutErrorssleepsunlocksNotLockedError(shitwaits workintervalsislockedst0st1st2sprefixslockfile((s /var/mailman/Mailman/LockFile.pys_dochildõs>          cCsœy)tdƒ}|idƒ}|iƒWn_tj oS}|itijo‚ndk }|i t i ƒ t i ƒ ƒiƒ}nXti|ƒdS(Ns /dev/randomi((sopensfpsreadsdsclosesEnvironmentErrorseserrnosENOENTsshasnewsossgetpidstimes hexdigestsrandomsseed(sfpsesdssha((s /var/mailman/Mailman/LockFile.pys_seeds  ,cCs¤tiddƒ}x‹t|ƒD]}}d|d|fGHtiƒ}|oti|dƒ\}}qt ƒy t ƒWnt j onXti dƒqWdS(Niids Loop %d of %di(srandomsrandints loopcountsrangesisossforkspidswaitpidsstatuss_seeds_dochildsKeyboardInterrupts_exit(sstatuss loopcountsispid((s /var/mailman/Mailman/LockFile.pys_onetest*s   cCsG| odSntidtiƒ\}}|djo ||=ndS(Niÿÿÿÿi(skidssosswaitpidsWNOHANGspidsstatus(skidssstatusspid((s /var/mailman/Mailman/LockFile.pys_reap<s  cCsh}xjt|ƒD]\}tiƒ}|o|||        ÿy (