1 files changed, 48 insertions, 2 deletions

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index bcc4f243134..7e9408e61d9 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -318,7 +318,7 @@ interactive_getc(void)
 
 	c = getc(stdin);
 
-	ProcessClientReadInterrupt();
+	ProcessClientReadInterrupt(true);
 
 	return c;
 }
@@ -529,7 +529,7 @@ ReadCommand(StringInfo inBuf)
  * Must preserve errno!
  */
 void
-ProcessClientReadInterrupt(void)
+ProcessClientReadInterrupt(bool blocked)
 {
 	int			save_errno = errno;
 
@@ -546,10 +546,56 @@ ProcessClientReadInterrupt(void)
 		if (notifyInterruptPending)
 			ProcessNotifyInterrupt();
 	}
+	else if (ProcDiePending && blocked)
+	{
+		/*
+		 * We're dying. It's safe (and sane) to handle that now.
+		 */
+		CHECK_FOR_INTERRUPTS();
+	}
 
 	errno = save_errno;
 }
 
+/*
+ * ProcessClientWriteInterrupt() - Process interrupts specific to client writes
+ *
+ * This is called just after low-level writes. That might be after the read
+ * finished successfully, or it was interrupted via interrupt. 'blocked' tells
+ * us whether the
+ *
+ * Must preserve errno!
+ */
+void
+ProcessClientWriteInterrupt(bool blocked)
+{
+	int			save_errno = errno;
+
+	Assert(InterruptHoldoffCount == 0 && CritSectionCount == 0);
+
+	/*
+	 * We only want to process the interrupt here if socket writes are
+	 * blocking to increase the chance to get an error message to the
+	 * client. If we're not blocked there'll soon be a
+	 * CHECK_FOR_INTERRUPTS(). But if we're blocked we'll never get out of
+	 * that situation if the client has died.
+	 */
+	if (ProcDiePending && blocked)
+	{
+		/*
+		 * We're dying. It's safe (and sane) to handle that now. But we don't
+		 * want to send the client the error message as that a) would possibly
+		 * block again b) would possibly lead to sending an error message to
+		 * the client, while we already started to send something else.
+		 */
+		if (whereToSendOutput == DestRemote)
+			whereToSendOutput = DestNone;
+
+		CHECK_FOR_INTERRUPTS();
+	}
+
+	errno = save_errno;
+}
 
 /*
  * Do raw parsing (only).