#25939 [Com]: [PATCH] feof no longer detects connections closed by the server
ID: 25939
Comment by: topace at lightbox dot org
Reported By: mlemos at acm dot org
Status: Closed
Bug Type: Sockets related
Operating System: *
PHP Version: 4.3.4
New Comment:
This bug fix causes another bug. Im using Ilohamail
(http://www.ilohamail.org) and after upgrading to PHP
4.3.6, it would take several minutes to login to the
webmail system. The culprit I traced down to this
function:
function iil_ReadLine($fp, $size){
$line="";
if (($fp)&&(!feof($fp))){
do{
$buffer = fgets($fp, 1024);
$endID = strlen($buffer) - 1;
$end = (($buffer[$endID] == "\n")||
(feof($fp)));
$line.=$buffer;
}while(!$end);
}
if ((feof($fp)) && (!empty($line))) $line.="\n";
return $line;
}
the final line before the return... the feof($fp) is
BLOCKING until a timeout occurs (several minutes). The
feof($fp) should definitely not BLOCK!
Cheers,
James
Previous Comments:
------------------------------------------------------------------------
[2003-11-28 17:10:38] wez@php.net
This bug has been fixed in CVS.
In case this was a PHP problem, snapshots of the sources are packaged
every three hours; this change will be in the next snapshot. You can
grab the snapshot at http://snaps.php.net/.
In case this was a documentation problem, the fix will show up soon at
http://www.php.net/manual/.
In case this was a PHP.net website problem, the change will show
up on the PHP.net site and on the mirror sites in short time.
Thank you for the report, and for helping us make PHP better.
Thanks for the patch; I used a slightly different technique to fix the
problem, although the essence was very much the same, but moving the
peek into feof() itself.
------------------------------------------------------------------------
[2003-11-11 00:44:40] mlemos at acm dot org
Actually there is a small bug in the patch. Here is the correct
version:
*** network.c 2003-11-11 03:06:07.000000000 -0200
--- network.c.fixed 2003-11-10 18:41:16.000000000 -0200
***************
*** 1033,1038 ****
--- 1033,1049 ----
nr_bytes = recv(sock->socket, buf, count, 0);
stream->eof = (nr_bytes == 0 || (nr_bytes == -1 &&
php_socket_errno() != EWOULDBLOCK));
+
+ /* We did not reach the end of data but it did not
fill the buffer?
+ * Maybe the server closed the connection. Lets peek
ahead.
+ */
+ if (!stream->eof && (count - nr_bytes > 0)) {
+ int more_bytes;
+
+ more_bytes = recv(sock->socket, buf + nr_bytes,
1, MSG_PEEK);
+
+ stream->eof = (more_bytes == 0 || (more_bytes
== -1 && php_socket_errno() != EWOULDBLOCK));
+ }
}
if (nr_bytes > 0) {
------------------------------------------------------------------------
[2003-10-21 15:45:32] mlemos at acm dot org
Description:
------------
It seems that since the changes introduced after PHP 4.3.1, the feof
function is no longer returning true when the server closes the socket
connection after transmiting all the contents.
This seems to make it impossible to determine if there was a real
network error or the server closed the connection normally breaking the
compatibility of scripts that rely on feof to determine the end of
connection condition.
Reproduce code:
---------------
The following script demonstrates the change of behaviour. You should
try it either PHP versions before and after PHP 4.3.2 to see the
difference.
<?php
$socket=fsockopen("www.php.net",80,$error);
if(!$socket)
{
echo "socket opening error\n";
exit;
}
echo "connection opened\n";
if(!fputs($socket,"GET / HTTP/1.1\r\nHost:
www.php.net\r\n\r\n"))
{
echo "socket writing error\n";
exit;
}
while(!feof($socket))
{
$data=fread($socket,1000);
if(!$data)
{
echo "socket reading error\n";
exit;
}
echo "read ",strlen($data)," bytes\n";
}
echo "reached the end of data\n";
fclose($socket);
?>
Expected result:
----------------
connection opened
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 278 bytes
reached the end of data
Actual result:
--------------
connection opened
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 1000 bytes
read 278 bytes
socket reading error
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=25939&edit=1
Thread (6 messages)