Merge branch 'PHP-7.4' into PHP-8.0

* PHP-7.4:
  Fix #81302: Stream position after stream filter removed

Author: cmb69

NEWS

@@ -2,6 +2,8 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2021, PHP 8.0.11
 
+- Core:
+  . Fixed bug #81302 (Stream position after stream filter removed). (cmb)
 
 26 Aug 2021, PHP 8.0.10
 

ext/standard/tests/filters/bug81302.phpt

@@ -0,0 +1,20 @@
+--TEST--
+Bug #81302 (Stream position after stream filter removed)
+--SKIPIF--
+<?php
+if (!extension_loaded('zlib')) die("skip zlib extension not available");
+?>
+--FILE--
+<?php
+$f = fopen("php://memory", "w+b");
+$z = stream_filter_append($f, "zlib.deflate", STREAM_FILTER_WRITE, 6);
+fwrite($f, "Testing");
+stream_filter_remove($z);
+$pos = ftell($f);
+fseek($f, 0);
+$count = strlen(fread($f, 1024));
+fclose($f);
+var_dump($count === $pos);
+?>
+--EXPECT--
+bool(true)

main/streams/filter.c

@@ -468,7 +468,10 @@ PHPAPI int _php_stream_filter_flush(php_stream_filter *filter, int finish)
 	} else if (chain == &(stream->writefilters)) {
 		/* Send flushed data to the stream */
 		while ((bucket = inp->head)) {
-			stream->ops->write(stream, bucket->buf, bucket->buflen);
+			ssize_t count = stream->ops->write(stream, bucket->buf, bucket->buflen);
+			if (count > 0) {
+				stream->position += count;
+			}
 			php_stream_bucket_unlink(bucket);
 			php_stream_bucket_delref(bucket);
 		}