diff options
Diffstat (limited to 'src/backend/tcop/postgres.c')
| -rw-r--r-- | src/backend/tcop/postgres.c | 106 |
1 files changed, 40 insertions, 66 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 556e5633284..bcc4f243134 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -301,17 +301,25 @@ InteractiveBackend(StringInfo inBuf) * interactive_getc -- collect one character from stdin * * Even though we are not reading from a "client" process, we still want to - * respond to signals, particularly SIGTERM/SIGQUIT. Hence we must use - * prepare_for_client_read and client_read_ended. + * respond to signals, particularly SIGTERM/SIGQUIT. */ static int interactive_getc(void) { int c; - prepare_for_client_read(); + /* + * This will not process catchup interrupts or notifications while + * reading. But those can't really be relevant for a standalone backend + * anyway. To properly handle SIGTERM there's a hack in die() that + * directly processes interrupts at this stage... + */ + CHECK_FOR_INTERRUPTS(); + c = getc(stdin); - client_read_ended(); + + ProcessClientReadInterrupt(); + return c; } @@ -513,53 +521,33 @@ ReadCommand(StringInfo inBuf) } /* - * prepare_for_client_read -- set up to possibly block on client input + * ProcessClientReadInterrupt() - Process interrupts specific to client reads * - * This must be called immediately before any low-level read from the - * client connection. It is necessary to do it at a sufficiently low level - * that there won't be any other operations except the read kernel call - * itself between this call and the subsequent client_read_ended() call. - * In particular there mustn't be use of malloc() or other potentially - * non-reentrant libc functions. This restriction makes it safe for us - * to allow interrupt service routines to execute nontrivial code while - * we are waiting for input. - */ -void -prepare_for_client_read(void) -{ - if (DoingCommandRead) - { - /* Enable immediate processing of asynchronous signals */ - EnableNotifyInterrupt(); - EnableCatchupInterrupt(); - - /* Allow die interrupts to be processed while waiting */ - ImmediateInterruptOK = true; - - /* And don't forget to detect one that already arrived */ - CHECK_FOR_INTERRUPTS(); - } -} - -/* - * client_read_ended -- get out of the client-input state + * This is called just after low-level reads. That might be after the read + * finished successfully, or it was interrupted via interrupt. * - * This is called just after low-level reads. It must preserve errno! + * Must preserve errno! */ void -client_read_ended(void) +ProcessClientReadInterrupt(void) { + int save_errno = errno; + if (DoingCommandRead) { - int save_errno = errno; - - ImmediateInterruptOK = false; + /* Check for general interrupts that arrived while reading */ + CHECK_FOR_INTERRUPTS(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); + /* Process sinval catchup interrupts that happened while reading */ + if (catchupInterruptPending) + ProcessCatchupInterrupt(); - errno = save_errno; + /* Process sinval catchup interrupts that happened while reading */ + if (notifyInterruptPending) + ProcessNotifyInterrupt(); } + + errno = save_errno; } @@ -2626,6 +2614,15 @@ die(SIGNAL_ARGS) /* If we're still here, waken anything waiting on the process latch */ SetLatch(MyLatch); + /* + * If we're in single user mode, we want to quit immediately - we can't + * rely on latches as they wouldn't work when stdin/stdout is a + * file. Rather ugly, but it's unlikely to be worthwhile to invest much + * more effort just for the benefit of single user mode. + */ + if (DoingCommandRead && whereToSendOutput != DestRemote) + ProcessInterrupts(); + errno = save_errno; } @@ -2834,8 +2831,6 @@ ProcessInterrupts(void) QueryCancelPending = false; /* ProcDie trumps QueryCancel */ ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); /* As in quickdie, don't risk sending to client during auth */ if (ClientAuthInProgress && whereToSendOutput == DestRemote) whereToSendOutput = DestNone; @@ -2871,8 +2866,6 @@ ProcessInterrupts(void) QueryCancelPending = false; /* lost connection trumps QueryCancel */ ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); /* don't send to client, we already know the connection to be dead. */ whereToSendOutput = DestNone; ereport(FATAL, @@ -2892,8 +2885,6 @@ ProcessInterrupts(void) ImmediateInterruptOK = false; /* not idle anymore */ RecoveryConflictPending = false; LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(FATAL, (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE), @@ -2926,8 +2917,6 @@ ProcessInterrupts(void) { ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); /* As in quickdie, don't risk sending to client during auth */ if (whereToSendOutput == DestRemote) whereToSendOutput = DestNone; @@ -2945,8 +2934,6 @@ ProcessInterrupts(void) ImmediateInterruptOK = false; /* not idle anymore */ (void) get_timeout_indicator(STATEMENT_TIMEOUT, true); LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); ereport(ERROR, (errcode(ERRCODE_LOCK_NOT_AVAILABLE), errmsg("canceling statement due to lock timeout"))); @@ -2955,8 +2942,6 @@ ProcessInterrupts(void) { ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling statement due to statement timeout"))); @@ -2965,8 +2950,6 @@ ProcessInterrupts(void) { ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling autovacuum task"))); @@ -2976,8 +2959,6 @@ ProcessInterrupts(void) ImmediateInterruptOK = false; /* not idle anymore */ RecoveryConflictPending = false; LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); pgstat_report_recovery_conflict(RecoveryConflictReason); ereport(ERROR, (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE), @@ -2994,13 +2975,12 @@ ProcessInterrupts(void) { ImmediateInterruptOK = false; /* not idle anymore */ LockErrorCleanup(); - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); ereport(ERROR, (errcode(ERRCODE_QUERY_CANCELED), errmsg("canceling statement due to user request"))); } } + /* If we get here, do nothing (probably, QueryCancelPending was reset) */ } @@ -3843,14 +3823,8 @@ PostgresMain(int argc, char *argv[], disable_all_timeouts(false); QueryCancelPending = false; /* second to avoid race condition */ - /* - * Turn off these interrupts too. This is only needed here and not in - * other exception-catching places since these interrupts are only - * enabled while we wait for client input. - */ + /* Not reading from the client anymore. */ DoingCommandRead = false; - DisableNotifyInterrupt(); - DisableCatchupInterrupt(); /* Make sure libpq is in a good state */ pq_comm_reset(); |