diff options
Diffstat (limited to 'src/backend/executor')
| -rw-r--r-- | src/backend/executor/spi.c | 102 |
1 files changed, 95 insertions, 7 deletions
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c index 995f67d2662..9fc4431b80c 100644 --- a/src/backend/executor/spi.c +++ b/src/backend/executor/spi.c @@ -83,6 +83,12 @@ static bool _SPI_checktuples(void); int SPI_connect(void) { + return SPI_connect_ext(0); +} + +int +SPI_connect_ext(int options) +{ int newdepth; /* Enlarge stack if necessary */ @@ -92,7 +98,7 @@ SPI_connect(void) elog(ERROR, "SPI stack corrupted"); newdepth = 16; _SPI_stack = (_SPI_connection *) - MemoryContextAlloc(TopTransactionContext, + MemoryContextAlloc(TopMemoryContext, newdepth * sizeof(_SPI_connection)); _SPI_stack_depth = newdepth; } @@ -124,19 +130,25 @@ SPI_connect(void) _SPI_current->execCxt = NULL; _SPI_current->connectSubid = GetCurrentSubTransactionId(); _SPI_current->queryEnv = NULL; + _SPI_current->atomic = (options & SPI_OPT_NONATOMIC ? false : true); + _SPI_current->internal_xact = false; /* * Create memory contexts for this procedure * - * XXX it would be better to use PortalContext as the parent context, but - * we may not be inside a portal (consider deferred-trigger execution). - * Perhaps CurTransactionContext would do? For now it doesn't matter - * because we clean up explicitly in AtEOSubXact_SPI(). + * In atomic contexts (the normal case), we use TopTransactionContext, + * otherwise PortalContext, so that it lives across transaction + * boundaries. + * + * XXX It could be better to use PortalContext as the parent context in + * all cases, but we may not be inside a portal (consider deferred-trigger + * execution). Perhaps CurTransactionContext could be an option? For now + * it doesn't matter because we clean up explicitly in AtEOSubXact_SPI(). */ - _SPI_current->procCxt = AllocSetContextCreate(TopTransactionContext, + _SPI_current->procCxt = AllocSetContextCreate(_SPI_current->atomic ? TopTransactionContext : PortalContext, "SPI Proc", ALLOCSET_DEFAULT_SIZES); - _SPI_current->execCxt = AllocSetContextCreate(TopTransactionContext, + _SPI_current->execCxt = AllocSetContextCreate(_SPI_current->atomic ? TopTransactionContext : _SPI_current->procCxt, "SPI Exec", ALLOCSET_DEFAULT_SIZES); /* ... and switch to procedure's context */ @@ -181,6 +193,73 @@ SPI_finish(void) return SPI_OK_FINISH; } +void +SPI_start_transaction(void) +{ + MemoryContext oldcontext = CurrentMemoryContext; + + StartTransactionCommand(); + MemoryContextSwitchTo(oldcontext); +} + +void +SPI_commit(void) +{ + MemoryContext oldcontext = CurrentMemoryContext; + + if (_SPI_current->atomic) + ereport(ERROR, + (errcode(ERRCODE_INVALID_TRANSACTION_TERMINATION), + errmsg("invalid transaction termination"))); + + /* + * This restriction is required by PLs implemented on top of SPI. They + * use subtransactions to establish exception blocks that are supposed to + * be rolled back together if there is an error. Terminating the + * top-level transaction in such a block violates that idea. A future PL + * implementation might have different ideas about this, in which case + * this restriction would have to be refined or the check possibly be + * moved out of SPI into the PLs. + */ + if (IsSubTransaction()) + ereport(ERROR, + (errcode(ERRCODE_INVALID_TRANSACTION_TERMINATION), + errmsg("cannot commit while a subtransaction is active"))); + + _SPI_current->internal_xact = true; + + if (ActiveSnapshotSet()) + PopActiveSnapshot(); + CommitTransactionCommand(); + MemoryContextSwitchTo(oldcontext); + + _SPI_current->internal_xact = false; +} + +void +SPI_rollback(void) +{ + MemoryContext oldcontext = CurrentMemoryContext; + + if (_SPI_current->atomic) + ereport(ERROR, + (errcode(ERRCODE_INVALID_TRANSACTION_TERMINATION), + errmsg("invalid transaction termination"))); + + /* see under SPI_commit() */ + if (IsSubTransaction()) + ereport(ERROR, + (errcode(ERRCODE_INVALID_TRANSACTION_TERMINATION), + errmsg("cannot roll back while a subtransaction is active"))); + + _SPI_current->internal_xact = true; + + AbortCurrentTransaction(); + MemoryContextSwitchTo(oldcontext); + + _SPI_current->internal_xact = false; +} + /* * Clean up SPI state at transaction commit or abort. */ @@ -188,6 +267,12 @@ void AtEOXact_SPI(bool isCommit) { /* + * Do nothing if the transaction end was initiated by SPI. + */ + if (_SPI_current && _SPI_current->internal_xact) + return; + + /* * Note that memory contexts belonging to SPI stack entries will be freed * automatically, so we can ignore them here. We just need to restore our * static variables to initial state. @@ -224,6 +309,9 @@ AtEOSubXact_SPI(bool isCommit, SubTransactionId mySubid) if (connection->connectSubid != mySubid) break; /* couldn't be any underneath it either */ + if (connection->internal_xact) + break; + found = true; /* |