Using PHP to read a web page with fsockopen(), but fgets is not working
Im using this code here: http://www.digiways.com/articles/php/httpredirects/
public function ReadHttpFile($strUrl, $iHttpRedirectMaxRecursiveCalls = 5)
{
// parsing the url getting web server name/IP, path and port.
$url = parse_url($strUrl);
// setting path to '/' if not present in $strUrl
if (isset($url['path']) === false)
$url['path'] = '/';
// setting port to default HTTP server port 80
if (isset($url['port']) === false)
$url['port'] = 80;
// connecting to the server]
// reseting class data
$this->success = false;
unset($this->strFile);
unset($this->aHeaderLines);
$this->strLocation = $strUrl开发者_开发知识库;
$fp = fsockopen ($url['host'], $url['port'], $errno, $errstr, 30);
// Return if the socket was not open $this->success is set to false.
if (!$fp)
return;
$header = 'GET / HTTP/1.1\r\n';
$header .= 'Host: '.$url['host'].$url['path'];
if (isset($url['query']))
$header .= '?'.$url['query'];
$header .= '\r\n';
$header .= 'Connection: Close\r\n\r\n';
// sending the request to the server
echo "Header is: <br />".str_replace('\n', '\n<br />', $header)."<br />";
$length = strlen($header);
if($length != fwrite($fp, $header, $length))
{
echo 'error writing to header, exiting<br />';
return;
}
// $bHeader is set to true while we receive the HTTP header
// and after the empty line (end of HTTP header) it's set to false.
$bHeader = true;
// continuing untill there's no more text to read from the socket
while (!feof($fp))
{
echo "in loop";
// reading a line of text from the socket
// not more than 8192 symbols.
$good = $strLine = fgets($fp, 128);
if(!$good)
{
echo 'bad';
return;
}
// removing trailing \n and \r characters.
$strLine = ereg_replace('[\r\n]', '', $strLine);
if ($bHeader == false)
$this->strFile .= $strLine.'\n';
else
$this->aHeaderLines[] = trim($strLine);
if (strlen($strLine) == 0)
$bHeader = false;
echo "read: $strLine<br />";
return;
}
echo "<br />after loop<br />";
fclose ($fp);
}
This is all I get:
Header is:
GET / HTTP/1.1\r\n
Host: www.google.com/\r\n
Connection: Close\r\n\r\n
in loopbad
So it fails the fgets($fp, 128);
Is there a reason you aren't using PHP's built-in, enabled-by-default ability to fetch remote files using fopen?
$remote_page = file_get_contents('http://www.google.com/'); // <- Works!
There are also plenty of high-quality third-party libraries, if you need to do something like fetch headers without thinking too hard. Try Zend_Http_Client on for size.
The flaw is here:
$good = $strLine = fgets($fp, 128);
if(!$good)
{
echo 'bad';
return;
}
fgets()
returns either a string on success, or FALSE on failure. However, if there was no more data to be returned, fgets() will return the empty string (''
). So, both $good
and $strLine
are set to the empty string, which PHP will happily cast to FALSE in the if()
test. You should rewrite as follows:
$strLine = fgets($fp, 128);
if ($strLine === FALSE) { // strict comparison - types and values must match
echo 'bad';
return;
}
There's no need for the double assignment, as you can test $strLine
directly.
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