0001-server-notify-fix.patch

diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c
index d349d7c..2880736 100644
--- a/src/backend/libpq/be-secure.c
+++ b/src/backend/libpq/be-secure.c
@@ -145,6 +145,16 @@ secure_read(Port *port, void *ptr, size_t len)
 	ssize_t		n;
 	int			waitfor;
 
+	/*
+	 * We might already have a pending interrupt condition to deal with.  If
+	 * the process latch is set, that would cause us to fall through the read
+	 * and handle the condition below --- but the latch might have been
+	 * cleared since the condition interrupt happened.  This is cheap enough
+	 * (if there's nothing to do) that it's not worth being too tense about
+	 * avoiding it.
+	 */
+	ProcessClientReadInterrupt();
+
 retry:
 #ifdef USE_SSL
 	waitfor = 0;
@@ -197,7 +207,7 @@ retry:
 		if (event.events & WL_LATCH_SET)
 		{
 			ResetLatch(MyLatch);
-			ProcessClientReadInterrupt(true);
+			ProcessClientReadInterrupt();
 
 			/*
 			 * We'll retry the read. Most likely it will return immediately
@@ -209,11 +219,10 @@ retry:
 	}
 
 	/*
-	 * Process interrupts that happened while (or before) receiving. Note that
-	 * we signal that we're not blocking, which will prevent some types of
-	 * interrupts from being processed.
+	 * Process interrupts that happened during a successful (or hard-failed)
+	 * read.
 	 */
-	ProcessClientReadInterrupt(false);
+	ProcessClientReadInterrupt();
 
 	return n;
 }
@@ -248,6 +257,16 @@ secure_write(Port *port, void *ptr, size_t len)
 	ssize_t		n;
 	int			waitfor;
 
+	/*
+	 * We might already have a pending interrupt condition to deal with.  If
+	 * the process latch is set, that would cause us to fall through the write
+	 * and handle the condition below --- but the latch might have been
+	 * cleared since the condition interrupt happened.  This is cheap enough
+	 * (if there's nothing to do) that it's not worth being too tense about
+	 * avoiding it.
+	 */
+	ProcessClientWriteInterrupt();
+
 retry:
 	waitfor = 0;
 #ifdef USE_SSL
@@ -283,7 +302,7 @@ retry:
 		if (event.events & WL_LATCH_SET)
 		{
 			ResetLatch(MyLatch);
-			ProcessClientWriteInterrupt(true);
+			ProcessClientWriteInterrupt();
 
 			/*
 			 * We'll retry the write. Most likely it will return immediately
@@ -295,11 +314,10 @@ retry:
 	}
 
 	/*
-	 * Process interrupts that happened while (or before) sending. Note that
-	 * we signal that we're not blocking, which will prevent some types of
-	 * interrupts from being processed.
+	 * Process interrupts that happened during a successful (or hard-failed)
+	 * write.
 	 */
-	ProcessClientWriteInterrupt(false);
+	ProcessClientWriteInterrupt();
 
 	return n;
 }
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index e4c6e3d..57f8075 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -315,7 +315,7 @@ interactive_getc(void)
 
 	c = getc(stdin);
 
-	ProcessClientReadInterrupt(true);
+	ProcessClientReadInterrupt();
 
 	return c;
 }
@@ -520,13 +520,12 @@ ReadCommand(StringInfo inBuf)
 /*
  * ProcessClientReadInterrupt() - Process interrupts specific to client reads
  *
- * 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 before and after low-level reads.
  *
  * Must preserve errno!
  */
 void
-ProcessClientReadInterrupt(bool blocked)
+ProcessClientReadInterrupt(void)
 {
 	int			save_errno = errno;
 
@@ -543,7 +542,7 @@ ProcessClientReadInterrupt(bool blocked)
 		if (notifyInterruptPending)
 			ProcessNotifyInterrupt();
 	}
-	else if (ProcDiePending && blocked)
+	else if (ProcDiePending)
 	{
 		/*
 		 * We're dying. It's safe (and sane) to handle that now.
@@ -557,25 +556,16 @@ ProcessClientReadInterrupt(bool blocked)
 /*
  * 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
+ * This is called just before and after low-level writes.
  *
  * Must preserve errno!
  */
 void
-ProcessClientWriteInterrupt(bool blocked)
+ProcessClientWriteInterrupt(void)
 {
 	int			save_errno = errno;
 
-	/*
-	 * 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)
+	if (ProcDiePending)
 	{
 		/*
 		 * We're dying. It's safe (and sane) to handle that now. But we don't
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index 63b4e48..8051d9a 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -71,8 +71,8 @@ extern void StatementCancelHandler(SIGNAL_ARGS);
 extern void FloatExceptionHandler(SIGNAL_ARGS) pg_attribute_noreturn();
 extern void RecoveryConflictInterrupt(ProcSignalReason reason); /* called from SIGUSR1
 																 * handler */
-extern void ProcessClientReadInterrupt(bool blocked);
-extern void ProcessClientWriteInterrupt(bool blocked);
+extern void ProcessClientReadInterrupt(void);
+extern void ProcessClientWriteInterrupt(void);
 
 extern void process_postgres_switches(int argc, char *argv[],
 						  GucContext ctx, const char **dbname);