o w[e-@sVdZddlZddlZddlZddlZddgZ dZ e Z Gdddej jZd d dZdS) aA dumb and slow but simple dbm clone. For database spam, spam.dir contains the index (a text file), spam.bak *may* contain a backup of the index (also a text file), while spam.dat contains the data (a binary file). XXX TO DO: - seems to contain a bug when updating... - reclaim free space (currently, space once occupied by deleted or expanded items is never reused) - support concurrent access (currently, if two processes take turns making updates, they can mess up the index) - support efficient access to large databases (currently, the whole index is read when the database is opened, and some updates rewrite the whole index) - support opening for read-only (flag = 'm') Nerroropenic@seZdZeZeZd+ddZddZddZdd ZeZ d d Z d d Z ddZ ddZ ddZddZddZddZddZddZddZeZd d!Zd"d#ZeZd$d%Zd&d'Zd(d)Zd*S), _DatabaseccCsL||_|dk|_|d|_|d|_|d|_d|_||||dS)Nrz.dirz.datz.bak)_mode _readonly_dirfile_datfile_bakfile_index_create_update)self filebasenamemodeflagr/usr/lib/python3.10/dbm/dumb.py__init__0s     z_Database.__init__c Cs|dkr|j|j|jfD]}zt|Wq tyYq wz tj|jddd}Wn0tyZ|dvr6tj|jddd}||jWdYdS1sRwYYdSw| dS)NnrLatin-1encodingrrw) r r r _osremoveOSError_ior_chmodclose)rrfilenamefrrrr Is"  & z_Database._createcCsd|_i|_z tj|jddd}Wnty#|dvrd|_YdSw|#|D]}|}t|\}}| d}||j|<q)WddS1sLwYdS)NFrrrrT) _modifiedr rrr rrstrip_ast literal_evalencode)rrr#linekeypos_and_siz_pairrrrr\s"    "z_Database._updatecCs|jdus|js dSz |j|jWn tyYnwz |j|j|jWn ty1Ynw|jj |jddd'}| |j|j D]\}}d| d|f}| |qHWddS1sfwYdS)Nrrr%r, %r )r r$runlinkr rrenamer rrr itemsdecodewrite)rr#r*r+entryrrr_commitps&    "z_Database._commitcCs|jdur tddSN"DBM object has already been closed)r rrrrr _verify_opens z_Database._verify_opencCsrt|tr |d}||j|\}}t|jd}||| |}Wd|S1s2wY|S)Nutf-8rb) isinstancestrr(r7r rrr seekread)rr*possizr#datrrr __getitem__s     z_Database.__getitem__cCst|jd.}|ddt|}|tdtt}|d|||}||Wdn1s8wY|t|fS)Nrb+r) rrr r<inttell _BLOCKSIZEr1len)rvalr#r>nposrrr_addvals    z_Database._addvalcCsNt|jd}||||Wdn1swY|t|fS)NrB)rrr r<r1rI)rr>rJr#rrr_setvals    z_Database._setvalcCsf||j|<tj|jddd}||j|d|d|fWddS1s,wYdS)Narrr,)r rrr r r1r0)rr*r+r#rrr_addkeys  "z_Database._addkeycCs|jrtdt|tr|d}n t|ttfstdt|tr(|d}n t|ttfs3td|d|_ ||j vrJ| || |dS|j |\}}|t dt }t|t dt }||krr||||j |<dS| ||j |<dS)N'The database is opened for reading onlyr8zkeys must be bytes or stringszvalues must be bytes or stringsTrD)rrr:r;r(bytes bytearray TypeErrorr7r$r rOrLrHrIrM)rr*rJr>r? oldblocks newblocksrrr __setitem__s(     z_Database.__setitem__cCsD|jrtdt|tr|d}|d|_|j|=|dS)NrPr8T) rrr:r;r(r7r$r r3rr*rrr __delitem__s   z_Database.__delitem__cC&zt|jWStytddwr4)listr rSrr6rrrkeys    z_Database.keyscs fddjDS)Ncsg|]}||fqSrr).0r*r6rr sz#_Database.items..)r7r r[r6rr6rr/sz_Database.itemscCsFt|tr |d}z||jvWSty"|jdur!tddw)Nr8r5)r:r;r(r rSrrWrrr __contains__s      z_Database.__contains__cCrYr4)iterr rSrr6rrriterkeysr\z_Database.iterkeyscCrYr4)rIr rSrr6rrr__len__ r\z_Database.__len__c CsBz|Wd|_|_|_|_dSd|_|_|_|_wN)r3r r r r r6rrrr!s 6z_Database.closecCs|j||jdSrc)rchmodr)rfilerrrr sz_Database._chmodcCs|Srcrr6rrr __enter__sz_Database.__enter__cGs |dSrc)r!)rargsrrr__exit__s z_Database.__exit__N)r)__name__ __module__ __qualname__rrrr rr3syncr7rArLrMrOrVrXr[r/r_ra__iter__rbr!__del__r rfrhrrrrr#s4   %  rrcCsTz td}t|Wn tyYnw||@}|dvr#tdt|||dS)aEOpen the database file, filename, and return corresponding object. The flag argument, used to control how the database is opened in the other DBM implementations, supports only the semantics of 'c' and 'n' values. Other values will default to the semantics of 'c' value: the database will always opened for update and will be created if it does not exist. The optional mode argument is the UNIX mode of the file, used only when the database has to be created. It defaults to octal code 0o666 (and will be modified by the prevailing umask). r)rrrrz)Flag must be one of 'r', 'w', 'c', or 'n')r)rumaskAttributeError ValueErrorr)rerrumrrrr"s   )rro)__doc__astr&iorosrcollections.abc collections__all__rHrrabcMutableMappingrrrrrrs