Fix #65483: quoted-printable encode stream filter incorrectly encoding spaces

Author: slusarz

NEWS

@@ -5,6 +5,8 @@ PHP                                                                        NEWS
 - Core:
   . Fixed bug #65490 (Duplicate calls to get lineno & filename for 
     DTRACE_FUNCTION_*). (Chris Jones)
+  . Fixed bug #65483 (quoted-printable encode stream filter incorrectly encoding
+    spaces). (Michael M Slusarz)
   . Fixed bug #65481 (shutdown segfault due to serialize) (Mike)
   . Fixed bug #65470 (Segmentation fault in zend_error() with 
     --enable-dtrace). (Chris Jones, Kris Van Hees)

ext/standard/filters.c

@@ -951,7 +951,9 @@ static php_conv_err_t php_conv_qprint_encode_convert(php_conv_qprint_encode *ins
 			*(pd++) = qp_digits[(c & 0x0f)];
 			ocnt -= 3;
 			line_ccnt -= 3;
-			trail_ws--;
+			if (trail_ws > 0) {
+				trail_ws--;
+			}
 			CONSUME_CHAR(ps, icnt, lb_ptr, lb_cnt);
 		}
 	}

ext/standard/tests/streams/bug65483.phpt

@@ -0,0 +1,19 @@
+--TEST--
+Bug #65483: quoted-printable encode stream filter incorrectly encoding spaces
+--FILE--
+<?php
+
+$data = 'a b=c d';
+
+$fd = fopen('php://temp', 'w+');
+fwrite($fd, $data);
+rewind($fd);
+
+$res = stream_filter_append($fd, 'convert.quoted-printable-encode', STREAM_FILTER_READ);
+var_dump(stream_get_contents($fd, -1, 0));
+
+fclose($fd);
+
+?>
+--EXPECT--
+string(9) "a b=3Dc d"