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Diffstat (limited to 'src/backend/tcop/postgres.c')
-rw-r--r--src/backend/tcop/postgres.c148
1 files changed, 95 insertions, 53 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 2644a146f92..664c7735754 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -341,6 +341,8 @@ SocketBackend(StringInfo inBuf)
/*
* Get message type code from the frontend.
*/
+ HOLD_CANCEL_INTERRUPTS();
+ pq_startmsgread();
qtype = pq_getbyte();
if (qtype == EOF) /* frontend disconnected */
@@ -377,8 +379,17 @@ SocketBackend(StringInfo inBuf)
break;
case 'F': /* fastpath function call */
- /* we let fastpath.c cope with old-style input of this */
doing_extended_query_message = false;
+ if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
+ {
+ if (GetOldFunctionMessage(inBuf))
+ {
+ ereport(COMMERROR,
+ (errcode(ERRCODE_PROTOCOL_VIOLATION),
+ errmsg("unexpected EOF on client connection")));
+ return EOF;
+ }
+ }
break;
case 'X': /* terminate */
@@ -446,6 +457,9 @@ SocketBackend(StringInfo inBuf)
if (pq_getmessage(inBuf, 0))
return EOF; /* suitable message already logged */
}
+ else
+ pq_endmsgread();
+ RESUME_CANCEL_INTERRUPTS();
return qtype;
}
@@ -490,7 +504,7 @@ prepare_for_client_read(void)
EnableNotifyInterrupt();
EnableCatchupInterrupt();
- /* Allow cancel/die interrupts to be processed while waiting */
+ /* Allow die interrupts to be processed while waiting */
ImmediateInterruptOK = true;
/* And don't forget to detect one that already arrived */
@@ -2677,21 +2691,11 @@ die(SIGNAL_ARGS)
ProcDiePending = true;
/*
- * If it's safe to interrupt, and we're waiting for input or a lock,
- * service the interrupt immediately
+ * If we're waiting for input or a lock so that it's safe to
+ * interrupt, service the interrupt immediately
*/
- if (ImmediateInterruptOK && InterruptHoldoffCount == 0 &&
- CritSectionCount == 0)
- {
- /* bump holdoff count to make ProcessInterrupts() a no-op */
- /* until we are done getting ready for it */
- InterruptHoldoffCount++;
- LockWaitCancel(); /* prevent CheckDeadLock from running */
- DisableNotifyInterrupt();
- DisableCatchupInterrupt();
- InterruptHoldoffCount--;
+ if (ImmediateInterruptOK)
ProcessInterrupts();
- }
}
errno = save_errno;
@@ -2715,21 +2719,11 @@ StatementCancelHandler(SIGNAL_ARGS)
QueryCancelPending = true;
/*
- * If it's safe to interrupt, and we're waiting for input or a lock,
- * service the interrupt immediately
+ * If we're waiting for input or a lock so that it's safe to
+ * interrupt, service the interrupt immediately
*/
- if (ImmediateInterruptOK && InterruptHoldoffCount == 0 &&
- CritSectionCount == 0)
- {
- /* bump holdoff count to make ProcessInterrupts() a no-op */
- /* until we are done getting ready for it */
- InterruptHoldoffCount++;
- LockWaitCancel(); /* prevent CheckDeadLock from running */
- DisableNotifyInterrupt();
- DisableCatchupInterrupt();
- InterruptHoldoffCount--;
+ if (ImmediateInterruptOK)
ProcessInterrupts();
- }
}
errno = save_errno;
@@ -2862,21 +2856,11 @@ RecoveryConflictInterrupt(ProcSignalReason reason)
RecoveryConflictRetryable = false;
/*
- * If it's safe to interrupt, and we're waiting for input or a lock,
- * service the interrupt immediately
+ * If we're waiting for input or a lock so that it's safe to
+ * interrupt, service the interrupt immediately.
*/
- if (ImmediateInterruptOK && InterruptHoldoffCount == 0 &&
- CritSectionCount == 0)
- {
- /* bump holdoff count to make ProcessInterrupts() a no-op */
- /* until we are done getting ready for it */
- InterruptHoldoffCount++;
- LockWaitCancel(); /* prevent CheckDeadLock from running */
- DisableNotifyInterrupt();
- DisableCatchupInterrupt();
- InterruptHoldoffCount--;
+ if (ImmediateInterruptOK)
ProcessInterrupts();
- }
}
errno = save_errno;
@@ -2892,15 +2876,17 @@ RecoveryConflictInterrupt(ProcSignalReason reason)
void
ProcessInterrupts(void)
{
- /* OK to accept interrupt now? */
+ /* OK to accept any interrupts now? */
if (InterruptHoldoffCount != 0 || CritSectionCount != 0)
return;
InterruptPending = false;
+
if (ProcDiePending)
{
ProcDiePending = false;
QueryCancelPending = false; /* ProcDie trumps QueryCancel */
ImmediateInterruptOK = false; /* not idle anymore */
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
/* As in quickdie, don't risk sending to client during auth */
@@ -2925,12 +2911,52 @@ ProcessInterrupts(void)
(errcode(ERRCODE_ADMIN_SHUTDOWN),
errmsg("terminating connection due to administrator command")));
}
+
+ /*
+ * If a recovery conflict happens while we are waiting for input from the
+ * client, the client is presumably just sitting idle in a transaction,
+ * preventing recovery from making progress. Terminate the connection to
+ * dislodge it.
+ */
+ if (RecoveryConflictPending && DoingCommandRead)
+ {
+ QueryCancelPending = false; /* this trumps QueryCancel */
+ ImmediateInterruptOK = false; /* not idle anymore */
+ RecoveryConflictPending = false;
+ LockWaitCancel();
+ DisableNotifyInterrupt();
+ DisableCatchupInterrupt();
+ ereport(FATAL,
+ (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+ errmsg("terminating connection due to conflict with recovery"),
+ errdetail_recovery_conflict(),
+ errhint("In a moment you should be able to reconnect to the"
+ " database and repeat your command.")));
+ }
+
if (QueryCancelPending)
{
+ /*
+ * Don't allow query cancel interrupts while reading input from the
+ * client, because we might lose sync in the FE/BE protocol. (Die
+ * interrupts are OK, because we won't read any further messages from
+ * the client in that case.)
+ */
+ if (QueryCancelHoldoffCount != 0)
+ {
+ /*
+ * Re-arm InterruptPending so that we process the cancel request
+ * as soon as we're done reading the message.
+ */
+ InterruptPending = true;
+ return;
+ }
+
QueryCancelPending = false;
if (ClientAuthInProgress)
{
ImmediateInterruptOK = false; /* not idle anymore */
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
/* As in quickdie, don't risk sending to client during auth */
@@ -2943,6 +2969,7 @@ ProcessInterrupts(void)
if (cancel_from_timeout)
{
ImmediateInterruptOK = false; /* not idle anymore */
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
ereport(ERROR,
@@ -2952,6 +2979,7 @@ ProcessInterrupts(void)
if (IsAutoVacuumWorkerProcess())
{
ImmediateInterruptOK = false; /* not idle anymore */
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
ereport(ERROR,
@@ -2962,20 +2990,13 @@ ProcessInterrupts(void)
{
ImmediateInterruptOK = false; /* not idle anymore */
RecoveryConflictPending = false;
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
- if (DoingCommandRead)
- ereport(FATAL,
- (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
- errmsg("terminating connection due to conflict with recovery"),
- errdetail_recovery_conflict(),
- errhint("In a moment you should be able to reconnect to the"
- " database and repeat your command.")));
- else
- ereport(ERROR,
- (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
+ ereport(ERROR,
+ (errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
errmsg("canceling statement due to conflict with recovery"),
- errdetail_recovery_conflict()));
+ errdetail_recovery_conflict()));
}
/*
@@ -2986,6 +3007,7 @@ ProcessInterrupts(void)
if (!DoingCommandRead)
{
ImmediateInterruptOK = false; /* not idle anymore */
+ LockWaitCancel();
DisableNotifyInterrupt();
DisableCatchupInterrupt();
ereport(ERROR,
@@ -3858,6 +3880,19 @@ PostgresMain(int argc, char *argv[],
/* We don't have a transaction command open anymore */
xact_started = false;
+ /*
+ * If an error occurred while we were reading a message from the
+ * client, we have potentially lost track of where the previous
+ * message ends and the next one begins. Even though we have
+ * otherwise recovered from the error, we cannot safely read any more
+ * messages from the client, so there isn't much we can do with the
+ * connection anymore.
+ */
+ if (pq_is_reading_msg())
+ ereport(FATAL,
+ (errcode(ERRCODE_PROTOCOL_VIOLATION),
+ errmsg("terminating connection because protocol sync was lost")));
+
/* Now we can allow interrupts again */
RESUME_INTERRUPTS();
}
@@ -3942,7 +3977,14 @@ PostgresMain(int argc, char *argv[],
/*
* (4) disable async signal conditions again.
+ *
+ * Query cancel is supposed to be a no-op when there is no query in
+ * progress, so if a query cancel arrived while we were idle, just
+ * reset QueryCancelPending. ProcessInterrupts() has that effect when
+ * it's called when DoingCommandRead is set, so check for interrupts
+ * before resetting DoingCommandRead.
*/
+ CHECK_FOR_INTERRUPTS();
DoingCommandRead = false;
/*
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-19 23:00:37 +0000