diff options
Diffstat (limited to 'src/backend/commands/trigger.c')
| -rw-r--r-- | src/backend/commands/trigger.c | 64 |
1 files changed, 34 insertions, 30 deletions
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 7e73f6b000f..18260e62729 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -7,7 +7,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.168 2004/08/29 05:06:41 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.169 2004/09/06 23:32:54 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1669,8 +1669,11 @@ ltrmark:; * state data; each subtransaction level that modifies that state first * saves a copy, which we use to restore the state if we abort. * - * numpushed and numalloc keep control of allocation and storage in the above - * stacks. numpushed is essentially the current subtransaction nesting depth. + * We use GetCurrentTransactionNestLevel() to determine the correct array + * index in these stacks. numalloc is the number of allocated entries in + * each stack. (By not keeping our own stack pointer, we can avoid trouble + * in cases where errors during subxact abort cause multiple invocations + * of DeferredTriggerEndSubXact() at the same nesting depth.) * * XXX We need to be able to save the per-event data in a file if it grows too * large. @@ -1742,7 +1745,6 @@ typedef struct DeferredTriggersData DeferredTriggerEvent *tail_stack; DeferredTriggerEvent *imm_stack; DeferredTriggerState *state_stack; - int numpushed; int numalloc; } DeferredTriggersData; @@ -2165,7 +2167,6 @@ DeferredTriggerBeginXact(void) deferredTriggers->imm_stack = NULL; deferredTriggers->state_stack = NULL; deferredTriggers->numalloc = 0; - deferredTriggers->numpushed = 0; } @@ -2251,6 +2252,8 @@ DeferredTriggerAbortXact(void) void DeferredTriggerBeginSubXact(void) { + int my_level = GetCurrentTransactionNestLevel(); + /* * Ignore call if the transaction is in aborted state. */ @@ -2260,7 +2263,7 @@ DeferredTriggerBeginSubXact(void) /* * Allocate more space in the stacks if needed. */ - if (deferredTriggers->numpushed == deferredTriggers->numalloc) + while (my_level >= deferredTriggers->numalloc) { if (deferredTriggers->numalloc == 0) { @@ -2282,32 +2285,28 @@ DeferredTriggerBeginSubXact(void) else { /* repalloc will keep the stacks in the same context */ - deferredTriggers->numalloc *= 2; + int new_alloc = deferredTriggers->numalloc * 2; deferredTriggers->tail_stack = (DeferredTriggerEvent *) repalloc(deferredTriggers->tail_stack, - deferredTriggers->numalloc * sizeof(DeferredTriggerEvent)); + new_alloc * sizeof(DeferredTriggerEvent)); deferredTriggers->imm_stack = (DeferredTriggerEvent *) repalloc(deferredTriggers->imm_stack, - deferredTriggers->numalloc * sizeof(DeferredTriggerEvent)); + new_alloc * sizeof(DeferredTriggerEvent)); deferredTriggers->state_stack = (DeferredTriggerState *) repalloc(deferredTriggers->state_stack, - deferredTriggers->numalloc * sizeof(DeferredTriggerState)); + new_alloc * sizeof(DeferredTriggerState)); + deferredTriggers->numalloc = new_alloc; } } /* - * Push the current list position into the stack and reset the - * pointer. + * Push the current information into the stack. */ - deferredTriggers->tail_stack[deferredTriggers->numpushed] = - deferredTriggers->tail_thisxact; - deferredTriggers->imm_stack[deferredTriggers->numpushed] = - deferredTriggers->events_imm; + deferredTriggers->tail_stack[my_level] = deferredTriggers->tail_thisxact; + deferredTriggers->imm_stack[my_level] = deferredTriggers->events_imm; /* State is not saved until/unless changed */ - deferredTriggers->state_stack[deferredTriggers->numpushed] = NULL; - - deferredTriggers->numpushed++; + deferredTriggers->state_stack[my_level] = NULL; } /* @@ -2318,6 +2317,7 @@ DeferredTriggerBeginSubXact(void) void DeferredTriggerEndSubXact(bool isCommit) { + int my_level = GetCurrentTransactionNestLevel(); DeferredTriggerState state; /* @@ -2327,18 +2327,18 @@ DeferredTriggerEndSubXact(bool isCommit) return; /* - * Move back the "top of the stack." + * Pop the prior state if needed. */ - Assert(deferredTriggers->numpushed > 0); - - deferredTriggers->numpushed--; + Assert(my_level < deferredTriggers->numalloc); if (isCommit) { /* If we saved a prior state, we don't need it anymore */ - state = deferredTriggers->state_stack[deferredTriggers->numpushed]; + state = deferredTriggers->state_stack[my_level]; if (state != NULL) pfree(state); + /* this avoids double pfree if error later: */ + deferredTriggers->state_stack[my_level] = NULL; } else { @@ -2346,9 +2346,9 @@ DeferredTriggerEndSubXact(bool isCommit) * Aborting --- restore the pointers from the stacks. */ deferredTriggers->tail_thisxact = - deferredTriggers->tail_stack[deferredTriggers->numpushed]; + deferredTriggers->tail_stack[my_level]; deferredTriggers->events_imm = - deferredTriggers->imm_stack[deferredTriggers->numpushed]; + deferredTriggers->imm_stack[my_level]; /* * Cleanup the head and the tail of the list. @@ -2367,12 +2367,14 @@ DeferredTriggerEndSubXact(bool isCommit) * Restore the trigger state. If the saved state is NULL, then * this subxact didn't save it, so it doesn't need restoring. */ - state = deferredTriggers->state_stack[deferredTriggers->numpushed]; + state = deferredTriggers->state_stack[my_level]; if (state != NULL) { pfree(deferredTriggers->state); deferredTriggers->state = state; } + /* this avoids double pfree if error later: */ + deferredTriggers->state_stack[my_level] = NULL; } } @@ -2457,6 +2459,8 @@ DeferredTriggerStateAddItem(DeferredTriggerState state, void DeferredTriggerSetState(ConstraintsSetStmt *stmt) { + int my_level = GetCurrentTransactionNestLevel(); + /* * Ignore call if we aren't in a transaction. */ @@ -2468,10 +2472,10 @@ DeferredTriggerSetState(ConstraintsSetStmt *stmt) * already, save it so it can be restored if the subtransaction * aborts. */ - if (deferredTriggers->numpushed > 0 && - deferredTriggers->state_stack[deferredTriggers->numpushed - 1] == NULL) + if (my_level > 1 && + deferredTriggers->state_stack[my_level] == NULL) { - deferredTriggers->state_stack[deferredTriggers->numpushed - 1] = + deferredTriggers->state_stack[my_level] = DeferredTriggerStateCopy(deferredTriggers->state); } |