From 150ebfdf77320b24b0358f8a903e90d7940ad4a4 Mon Sep 17 00:00:00 2001
From: George Peter Banyard <girgias@php.net>
Date: Wed, 23 Sep 2020 23:46:58 +0100
Subject: [PATCH] Suppress bogus [-Wlogical-op] warning from GCC

See GCC bug 69602: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602
which emits the warning for (errno == EWOULDBLOCK || errno == EAGAIN)
which is the correct way of handling errors as the value of EWOULDBLOCK
and EAGAIN is implementation defined.

Therefore introduce a new macro function PHP_IS_TRANSIENT_ERROR()
which handles the case when EWOULDBLOCK and EAGAIN are identical.

Thanks to @twose for the idea.
---
 ext/sockets/sockets.c        | 6 +-----
 main/php_network.h           | 7 +++++++
 main/streams/plain_wrapper.c | 4 ++--
 main/streams/xp_socket.c     | 5 +++--
 sapi/fpm/fpm/fpm_stdio.c     | 3 ++-
 5 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/ext/sockets/sockets.c b/ext/sockets/sockets.c
index 0b21c4f6843..c50d8d5d71b 100644
--- a/ext/sockets/sockets.c
+++ b/ext/sockets/sockets.c
@@ -1045,11 +1045,7 @@ PHP_FUNCTION(socket_read)
 	if (retval == -1) {
 		/* if the socket is in non-blocking mode and there's no data to read,
 		don't output any error, as this is a normal situation, and not an error */
-		if (errno == EAGAIN
-#ifdef EWOULDBLOCK
-		|| errno == EWOULDBLOCK
-#endif
-		) {
+		if (PHP_IS_TRANSIENT_ERROR(errno)) {
 			php_sock->error = errno;
 			SOCKETS_G(last_error) = errno;
 		} else {
diff --git a/main/php_network.h b/main/php_network.h
index 437069b4fcc..5c8cee3fa8a 100644
--- a/main/php_network.h
+++ b/main/php_network.h
@@ -49,6 +49,13 @@
 # define EWOULDBLOCK EAGAIN
 #endif
 
+/* This is a work around for GCC bug 69602: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602 */
+#if EAGAIN != EWOULDBLOCK
+# define PHP_IS_TRANSIENT_ERROR(err) (err == EAGAIN || err == EWOULDBLOCK)
+#else
+# define PHP_IS_TRANSIENT_ERROR(err) (err == EAGAIN)
+#endif
+
 #ifdef PHP_WIN32
 #define php_socket_errno() WSAGetLastError()
 #else
diff --git a/main/streams/plain_wrapper.c b/main/streams/plain_wrapper.c
index 8a891ddf720..0373cc4c947 100644
--- a/main/streams/plain_wrapper.c
+++ b/main/streams/plain_wrapper.c
@@ -351,7 +351,7 @@ static ssize_t php_stdiop_write(php_stream *stream, const char *buf, size_t coun
 		ssize_t bytes_written = write(data->fd, buf, count);
 #endif
 		if (bytes_written < 0) {
-			if (errno == EWOULDBLOCK || errno == EAGAIN) {
+			if (PHP_IS_TRANSIENT_ERROR(errno)) {
 				return 0;
 			}
 			if (errno == EINTR) {
@@ -420,7 +420,7 @@ static ssize_t php_stdiop_read(php_stream *stream, char *buf, size_t count)
 		}
 
 		if (ret < 0) {
-			if (errno == EWOULDBLOCK || errno == EAGAIN) {
+			if (PHP_IS_TRANSIENT_ERROR(errno)) {
 				/* Not an error. */
 				ret = 0;
 			} else if (errno == EINTR) {
diff --git a/main/streams/xp_socket.c b/main/streams/xp_socket.c
index f3370e89f7e..cd67fcb8ca3 100644
--- a/main/streams/xp_socket.c
+++ b/main/streams/xp_socket.c
@@ -75,7 +75,8 @@ retry:
 	if (didwrite <= 0) {
 		char *estr;
 		int err = php_socket_errno();
-		if (err == EWOULDBLOCK || err == EAGAIN) {
+
+		if (PHP_IS_TRANSIENT_ERROR(err)) {
 			if (sock->is_blocked) {
 				int retval;
 
@@ -166,7 +167,7 @@ static ssize_t php_sockop_read(php_stream *stream, char *buf, size_t count)
 	err = php_socket_errno();
 
 	if (nr_bytes < 0) {
-		if (err == EAGAIN || err == EWOULDBLOCK) {
+		if (PHP_IS_TRANSIENT_ERROR(err)) {
 			nr_bytes = 0;
 		} else {
 			stream->eof = 1;
diff --git a/sapi/fpm/fpm/fpm_stdio.c b/sapi/fpm/fpm/fpm_stdio.c
index 1742467b368..42ea1594301 100644
--- a/sapi/fpm/fpm/fpm_stdio.c
+++ b/sapi/fpm/fpm/fpm_stdio.c
@@ -10,6 +10,7 @@
 #include <errno.h>
 
 #include "php_syslog.h"
+#include "php_network.h"
 
 #include "fpm.h"
 #include "fpm_children.h"
@@ -166,7 +167,7 @@ static void fpm_stdio_child_said(struct fpm_event_s *ev, short which, void *arg)
 stdio_read:
 		in_buf = read(fd, buf, max_buf_size - 1);
 		if (in_buf <= 0) { /* no data */
-			if (in_buf == 0 || (errno != EAGAIN && errno != EWOULDBLOCK)) {
+			if (in_buf == 0 || !PHP_IS_TRANSIENT_ERROR(errno)) {
 				/* pipe is closed or error */
 				read_fail = (in_buf < 0) ? in_buf : 1;
 			}