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72 | use strict 'vars'; |
72 | use strict 'vars'; |
73 | |
73 | |
74 | use base 'Exporter'; |
74 | use base 'Exporter'; |
75 | |
75 | |
76 | BEGIN { |
76 | BEGIN { |
77 | our $VERSION = '1.0'; |
77 | our $VERSION = '1.1'; |
78 | |
78 | |
79 | our @BDB_REQ = qw( |
79 | our @BDB_REQ = qw( |
80 | db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect |
80 | db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect |
81 | db_env_memp_sync db_env_memp_trickle |
81 | db_env_memp_sync db_env_memp_trickle |
82 | db_open db_close db_compact db_sync db_put db_get db_pget db_del db_key_range |
82 | db_open db_close db_compact db_sync db_put db_get db_pget db_del db_key_range |
83 | db_txn_commit db_txn_abort |
83 | db_txn_commit db_txn_abort db_txn_finish |
84 | db_c_close db_c_count db_c_put db_c_get db_c_pget db_c_del |
84 | db_c_close db_c_count db_c_put db_c_get db_c_pget db_c_del |
85 | db_sequence_open db_sequence_close |
85 | db_sequence_open db_sequence_close |
86 | db_sequence_get db_sequence_remove |
86 | db_sequence_get db_sequence_remove |
87 | ); |
87 | ); |
88 | our @EXPORT = (@BDB_REQ, qw(dbreq_pri dbreq_nice db_env_create db_create)); |
88 | our @EXPORT = (@BDB_REQ, qw(dbreq_pri dbreq_nice db_env_create db_create)); |
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177 | db_sequence_get (DB_SEQUENCE *seq, DB_TXN_ornull *txnid, int delta, SV *seq_value, U32 flags = DB_TXN_NOSYNC, SV *callback = &PL_sv_undef) |
177 | db_sequence_get (DB_SEQUENCE *seq, DB_TXN_ornull *txnid, int delta, SV *seq_value, U32 flags = DB_TXN_NOSYNC, SV *callback = &PL_sv_undef) |
178 | flags: TXN_NOSYNC |
178 | flags: TXN_NOSYNC |
179 | db_sequence_remove (DB_SEQUENCE *seq, DB_TXN_ornull *txnid = 0, U32 flags = 0, SV *callback = &PL_sv_undef) |
179 | db_sequence_remove (DB_SEQUENCE *seq, DB_TXN_ornull *txnid = 0, U32 flags = 0, SV *callback = &PL_sv_undef) |
180 | flags: TXN_NOSYNC |
180 | flags: TXN_NOSYNC |
181 | |
181 | |
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182 | =head4 db_txn_finish (DB_TXN *txn, U32 flags = 0, SV *callback = &PL_sv_undef) |
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183 | |
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184 | This is not a Berkeley DB function but a BDB module extension. It is very |
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185 | annoying to have to check every single BDB function for error returns and |
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186 | provide a codepath out of your transaction. While the BDB module still |
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187 | makes this possible, it contains the following extensions: |
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188 | |
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189 | When a transaction-protected function returns any operating system |
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190 | error (errno > 0), BDB will set the C<TXN_DEADLOCK> flag on the |
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191 | transaction. This flag is also set by Berkeley DB functions externally |
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192 | when an operation fails with LOCK_DEADLOCK, and it causes all further |
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193 | operations on that transaction (including C<db_txn_commit>) to fail. |
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194 | |
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195 | The C<db_txn_finish> request will look at this flag, and, if it is set, |
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196 | will automatically call C<db_txn_abort> (setting errno to C<LOCK_DEADLOCK> |
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197 | if it isn't set). If it isn't set, it will call C<db_txn_commit> and |
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198 | return the error normally. |
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199 | |
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200 | How to use this? Easy: just write your transaction normally: |
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201 | |
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202 | my $txn = $db_env->txn_begin; |
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203 | db_get $db, $txn, "key", my $data; |
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204 | db_put $db, $txn, "key", $data + 1 unless $! == BDB::NOTFOUND; |
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205 | db_txn_finish $txn; |
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206 | die "transaction failed" if $!; |
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207 | |
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208 | That is, handle only the expected errors. If something unexpected happens |
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209 | (EIO, LOCK_NOTGRANTED or a deadlock in either db_get or db_put), then the remaining |
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210 | requests (db_put in this case) will simply be skipped (they will fail with |
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211 | LOCK_DEADLOCK) and the transaction will be aborted. |
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212 | |
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213 | You cna use the C<< $txn->failed >> method to check wether a transaction |
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214 | has failed in this way and abort further processing (excluding |
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215 | C<db_txn_finish>). |
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216 | |
182 | =head3 DB_ENV/database environment methods |
217 | =head3 DB_ENV/database environment methods |
183 | |
218 | |
184 | Methods available on DB_ENV/$env handles: |
219 | Methods available on DB_ENV/$env handles: |
185 | |
220 | |
186 | DESTROY (DB_ENV_ornull *env) |
221 | DESTROY (DB_ENV_ornull *env) |
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196 | $int = $env->set_flags (U32 flags, int onoff) |
231 | $int = $env->set_flags (U32 flags, int onoff) |
197 | $env->set_errfile (FILE *errfile = 0) |
232 | $env->set_errfile (FILE *errfile = 0) |
198 | $env->set_msgfile (FILE *msgfile = 0) |
233 | $env->set_msgfile (FILE *msgfile = 0) |
199 | $int = $env->set_verbose (U32 which, int onoff = 1) |
234 | $int = $env->set_verbose (U32 which, int onoff = 1) |
200 | $int = $env->set_encrypt (const char *password, U32 flags = 0) |
235 | $int = $env->set_encrypt (const char *password, U32 flags = 0) |
201 | $int = $env->set_timeout (NV timeout, U32 flags) |
236 | $int = $env->set_timeout (NV timeout_seconds, U32 flags = SET_TXN_TIMEOUT) |
202 | $int = $env->set_mp_max_openfd (int maxopenfd); |
237 | $int = $env->set_mp_max_openfd (int maxopenfd); |
203 | $int = $env->set_mp_max_write (int maxwrite, int maxwrite_sleep); |
238 | $int = $env->set_mp_max_write (int maxwrite, int maxwrite_sleep); |
204 | $int = $env->set_mp_mmapsize (int mmapsize_mb) |
239 | $int = $env->set_mp_mmapsize (int mmapsize_mb) |
205 | $int = $env->set_lk_detect (U32 detect = DB_LOCK_DEFAULT) |
240 | $int = $env->set_lk_detect (U32 detect = DB_LOCK_DEFAULT) |
206 | $int = $env->set_lk_max_lockers (U32 max) |
241 | $int = $env->set_lk_max_lockers (U32 max) |
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294 | DESTROY (DB_TXN_ornull *txn) |
329 | DESTROY (DB_TXN_ornull *txn) |
295 | CODE: |
330 | CODE: |
296 | if (txn) |
331 | if (txn) |
297 | txn->abort (txn); |
332 | txn->abort (txn); |
298 | |
333 | |
299 | $int = $txn->set_timeout (NV timeout, U32 flags) |
334 | $int = $txn->set_timeout (NV timeout_seconds, U32 flags = SET_TXN_TIMEOUT) |
300 | flags: SET_LOCK_TIMEOUT SET_TXN_TIMEOUT |
335 | flags: SET_LOCK_TIMEOUT SET_TXN_TIMEOUT |
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336 | |
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337 | $bool = $txn->failed |
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338 | # see db_txn_finish documentation, above |
301 | |
339 | |
302 | |
340 | |
303 | =head3 DBC/cursor methods |
341 | =head3 DBC/cursor methods |
304 | |
342 | |
305 | Methods available on DBC/$dbc handles: |
343 | Methods available on DBC/$dbc handles: |
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609 | temporary buffers, and each thread requires a stack and other data |
647 | temporary buffers, and each thread requires a stack and other data |
610 | structures (usually around 16k-128k, depending on the OS). |
648 | structures (usually around 16k-128k, depending on the OS). |
611 | |
649 | |
612 | =head1 KNOWN BUGS |
650 | =head1 KNOWN BUGS |
613 | |
651 | |
614 | Known bugs will be fixed in the next release. |
652 | Known bugs will be fixed in the next release, except: |
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653 | |
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654 | If you use a transaction in any request, and the request returns |
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655 | with an operating system error or DB_LOCK_NOTGRANTED, the internal |
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656 | TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>, |
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657 | above. |
615 | |
658 | |
616 | =head1 SEE ALSO |
659 | =head1 SEE ALSO |
617 | |
660 | |
618 | L<Coro::AIO>. |
661 | L<Coro::AIO>. |
619 | |
662 | |