From c37bd23189d60a359a3fd97d1a9d8b47d3689045 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Thu, 25 Mar 2021 14:13:59 +0100
Subject: [PATCH 1/3] Remove zero size special case for copy_to_stream

---
 main/streams/streams.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/main/streams/streams.c b/main/streams/streams.c
index 9bf744441269..430c3aa961bf 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1539,7 +1539,6 @@ PHPAPI int _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size
 	size_t haveread = 0;
 	size_t towrite;
 	size_t dummy;
-	php_stream_statbuf ssbuf;
 
 	if (!len) {
 		len = &dummy;
@@ -1554,17 +1553,6 @@ PHPAPI int _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size
 		maxlen = 0;
 	}
 
-	if (php_stream_stat(src, &ssbuf) == 0) {
-		if (ssbuf.sb.st_size == 0
-#ifdef S_ISREG
-			&& S_ISREG(ssbuf.sb.st_mode)
-#endif
-		) {
-			*len = 0;
-			return SUCCESS;
-		}
-	}
-
 	if (php_stream_mmap_possible(src)) {
 		char *p;
 

From 5f63fd871ed6282c582c25509f2a8dadba314119 Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Thu, 25 Mar 2021 18:44:15 +0100
Subject: [PATCH 2/3] Add test for copy from empty file

---
 .../file/stream_copy_to_stream_empty.phpt     | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 ext/standard/tests/file/stream_copy_to_stream_empty.phpt

diff --git a/ext/standard/tests/file/stream_copy_to_stream_empty.phpt b/ext/standard/tests/file/stream_copy_to_stream_empty.phpt
new file mode 100644
index 000000000000..43e659a5a285
--- /dev/null
+++ b/ext/standard/tests/file/stream_copy_to_stream_empty.phpt
@@ -0,0 +1,19 @@
+--TEST--
+stream_copy_to_stream() from empty file
+--FILE--
+<?php
+
+$tmp_empty_file = __FILE__ . ".tmp";
+file_put_contents($tmp_empty_file, "");
+
+$in = fopen($tmp_empty_file, 'r');
+$out = fopen('php://memory', 'w');
+var_dump(stream_copy_to_stream($in, $out));
+
+?>
+--CLEAN--
+<?php
+unlink(__FILE__ . ".tmp");
+?>
+--EXPECT--
+int(0)

From 7f973516c5f47272dc9319367bd1521e39f79b9e Mon Sep 17 00:00:00 2001
From: Nikita Popov <nikita.ppv@gmail.com>
Date: Thu, 25 Mar 2021 19:05:31 +0100
Subject: [PATCH 3/3] Remove weird code

---
 main/streams/streams.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/main/streams/streams.c b/main/streams/streams.c
index 430c3aa961bf..7df0dcce28d5 100644
--- a/main/streams/streams.c
+++ b/main/streams/streams.c
@@ -1629,20 +1629,13 @@ PHPAPI int _php_stream_copy_to_stream_ex(php_stream *src, php_stream *dest, size
 			writeptr += didwrite;
 		}
 
-		if (maxlen - haveread == 0) {
+		if (maxlen && maxlen == haveread) {
 			break;
 		}
 	}
 
 	*len = haveread;
-
-	/* we've got at least 1 byte to read.
-	 * less than 1 is an error */
-
-	if (haveread > 0 || src->eof) {
-		return SUCCESS;
-	}
-	return FAILURE;
+	return SUCCESS;
 }
 
 /* Returns the number of bytes moved.