readlink
I have also a short solution.
But Im not sure, if it is performant.
Explode-Array solution seems to work very fast.
function buildRelativePath($path){
$oldP = "";
$newP = $path;
while($newP!=$oldP){
$oldP = $newP;
$newP = preg_replace("/([^\/]+\/)([^\/]+\/)(\.\.\/)/ms","$1",$newP);
}
return str_replace("//","",str_replace("./","",$newP));
}
realpath
(PHP 4, PHP 5)
realpath — Returns canonicalized absolute pathname
Description
string realpath ( string $path )realpath() expands all symbolic links and resolves references to '/./', '/../' and extra '/' characters in the input path and return the canonicalized absolute pathname. The resulting path will have no symbolic link, '/./' or '/../' components.
realpath() returns FALSE on failure, e.g. if the file does not exist. On BSD systems realpath() doesn't fail if only the last path component doesn't exist, while other systems will return FALSE.
Example 652. realpath() example
<?php
chdir('/var/www/');
echo realpath('./../../etc/passwd');
?>
The above example will output:
/etc/passwd
See also basename(), dirname(), and pathinfo().
add a note
User Contributed Notesrealpath
adyballa at klingbim dot de
28-May-2007 03:55
28-May-2007 03:55
Sebastian
18-May-2007 12:00
18-May-2007 12:00
Who ever wrote the rp()-function. First of all, your function skips filenames or directories with "0" because you use == instead of === when comparing to an "empty" value. Second, the idea of realpath() isn't fixing useless "../" etc, but to resolve the full path of a relative directory/file or a symbolic link. So that if you run the script in '/usr/local/apache2/htdocs/' and exec realpath('uploads/test.txt') the output becomes '/usr/local/apache2/htdocs/uploads/test.txt' (as in the example)
I also wonder why the implementations aren't using the DIRECTORY_SEPARATOR constant and expect Unix.
Marc Noirot
03-May-2007 03:31
03-May-2007 03:31
Yet another realpath replacement:
function myRealPath($path) {
// Check if path begins with "/". => use === with strpos
if (strpos($path,"/") === 0) {
$path = $_SERVER['DOCUMENT_ROOT'].$path;
}
else {
// Strip slashes and convert to arrays.
$currentDir = preg_split("/\//",dirname($_SERVER['PATH_TRANSLATED']));
$newDir = preg_split('/\//',$path);
// Drop one directory from the array for each ".."; add one otherwise.
foreach ($newDir as $dir) {
if ($dir == "..")
array_pop($currentDir);
elseif ($dir != ".") //test for "." which represents current dir (do nothing in that case)
array_push($currentDir,$dir);
}
// Return the slashes.
$path = implode($currentDir,"/");
}
return $path;
}
01-Mar-2007 04:17
Tyron Madlener said "I just wonder why all the other solutions are so complex and that mine so simple".
Funny. I wonder why yours is so complex (26 lines, 2 functions) when it can be done in half that (13 lines, 1 function):
function rp($p) {
$p=explode('/', $p);
$o=array();
for ($i=0; $i<sizeof($p); $i++) {
if (''==$p[$i] || '.'==$p[$i]) continue;
if ('..'==$p[$i] && $i>0 && '..'!=$o[sizeof($o)-1]) {
array_pop($o);
continue;
}
array_push($o, $p[$i]);
}
return implode('/', $o);
}
With that, this:
print rp("../../xyz.txt")."\n";
print rp("a/b/c/d/../../xyz.txt")."\n";
print rp("a/b/c/d/../..//xyz.txt")."\n";
Prints:
../../xyz.txt
a/b/xyz.txt
a/b/xyz.txt
As expected.
Patrice Vanneufville
12-Feb-2007 11:29
12-Feb-2007 11:29
the precedent function does not work all the time : servers sometimes put a slash '/' at the end of $_SERVER['DOCUMENT_ROOT']
// transforme un chemin d'image relatif en chemin html absolu
function htmlpath($relative_path) {
$realpath = str_replace("\\", "/", realpath($relative_path));
$root = preg_replace(',/$,', '', $_SERVER['DOCUMENT_ROOT']);
if (strlen($root) && strpos($realpath, $root)===0)
return substr($realpath, strlen($root));
$dir = dirname(!empty($_SERVER['REQUEST_URI']) ? $_SERVER['REQUEST_URI'] :
(!empty($_SERVER['SCRIPT_NAME']) ? $_SERVER['SCRIPT_NAME'] :
(!empty($_SERVER['PHP_SELF']) ? $_SERVER['PHP_SELF'] : str_replace('\\','/',__FILE__)
)));
return canonicalize($dir.'/'.$relative_path);
}
// retourne un chemin canonique a partir d'un chemin contenant des ../
function canonicalize($address) {
$address = str_replace("//", "/", $address);
$address = explode('/', $address);
$keys = array_keys($address, '..');
foreach($keys as $keypos => $key) array_splice($address, $key - ($keypos * 2 + 1), 2);
$address = implode('/', $address);
return preg_replace(',([^.])\./,', '\1', $address);
}
Matthias Fostel
18-Jan-2007 02:52
18-Jan-2007 02:52
Popular htmlpath function found below with str_replace to fix issues with PHP on Windows.
function htmlpath($relative_path) {
$realpath=str_replace("\\", "/", realpath($relative_path));
$htmlpathURL=str_replace($_SERVER['DOCUMENT_ROOT'],'',$realpath);
return $htmlpathURL;
}
David Beck
23-Nov-2006 03:38
23-Nov-2006 03:38
Here's a function to canonicalize a URL containing relative paths. Ran into the problem when pulling links from a remote page.
<?php
function canonicalize($address)
{
$address = explode('/', $address);
$keys = array_keys($address, '..');
foreach($keys AS $keypos => $key)
{
array_splice($address, $key - ($keypos * 2 + 1), 2);
}
$address = implode('/', $address);
$address = str_replace('./', '', $address);
}
$url = 'http://www.example.com/something/../else';
echo canonicalize($url); //http://www.example.com/else
?>
bart at mediawave dot nl
21-Sep-2005 06:31
21-Sep-2005 06:31
Here's another function that resolves references to '/./', '/../' and extra '/' characters in the input path and returns the canonicalized pathname.
<?php
function cleanPath($path) {
$result = array();
// $pathA = preg_split('/[\/\\\]/', $path);
$pathA = explode('/', $path);
if (!$pathA[0])
$result[] = '';
foreach ($pathA AS $key => $dir) {
if ($dir == '..') {
if (end($result) == '..') {
$result[] = '..';
} elseif (!array_pop($result)) {
$result[] = '..';
}
} elseif ($dir && $dir != '.') {
$result[] = $dir;
}
}
if (!end($pathA))
$result[] = '';
return implode('/', $result);
}
echo 'input: ', $path = '..//./../dir4//./dir5/dir6/..//dir7/', '<br />';
echo 'output: ', cleanPath($path), '<br />';
?>
Will return:
input: ..//./../dir4//./dir5/dir6/..//dir7/
output: ../../dir4/dir5/dir7/
Jonny Rylands
14-Sep-2005 10:19
14-Sep-2005 10:19
Having problems with includes within include files,
particularly when the include files are in different directories?
This syntax allows:
* relative paths to be used in include strings.
* include files to include other files in different directories.
without getting file not found errors.
<?
include_once realpath(dirname(__FILE__)."/relative/path/to/include.inc.php");
?>
Tyron Madlener
14-Aug-2005 07:53
14-Aug-2005 07:53
None of the functions provided here worked for me. All of them somehow had the problem with pathes like '../../downloads/bar/../foo/..' or didn't provide relative paths.
So I coded my one that justs removes '.'-dirs from the paths and simplifies stuff like 'dir/..'
function SimplifyPath($path) {
$dirs = explode('/',$path);
for($i=0; $i<count($dirs);$i++) {
if($dirs[$i]=="." || $dirs[$i]=="") {
array_splice($dirs,$i,1);
$i--;
}
if($dirs[$i]=="..") {
$cnt = count($dirs);
$dirs=Simplify($dirs, $i);
$i-= $cnt-count($dirs);
}
}
return implode('/',$dirs);
}
function Simplify($dirs, $idx) {
if($idx==0) return $dirs;
if($dirs[$idx-1]=="..") Simplify($dirs, $idx-1);
else array_splice($dirs,$idx-1,2);
return $dirs;
}
I just wonder why all the other solutions are so complex and that mine so simple, because in general the problem of simplifieng isn't that hard to solve. Well, I hope that there aren't any cases on which my solution fails. Otherwise, feel free to improve :D
phpnote at web-milk dot co dot uk
22-Jul-2005 02:01
22-Jul-2005 02:01
I have written this function so that it does not matter whether the folder exists on the system. It simply traverses the given path moving up directories at every "/.." that it encounters. Though this can be used with a file at the end I would be cautious about using it with a query attached as any "/.." in the query will remove the text proir until the previous "/".
<?php
function htmlpath($relative_path)
{
$realpath = '';
$q = 0;
// Remove any ./
$relative_path = str_replace('/./', '/', $relative_path);
// Remove trailing /
if ($relative_path[strlen($relative_path)-1] == '/')
{
$relative_path = substr($relative_path, 0, -1);
}
$p = strpos($relative_path, '/..', $q);
while ($p !== false)
{
// Get the next part of the path
if ($p != $q) $realpath .= substr($relative_path, $q, $p);
// Find the edge of the previous directory
$i = strrpos($realpath, '/');
if ($i === false)
{
return false; // Not enough directories to go up any further.
}
// Remove the directory
$realpath = substr($realpath, 0, $i);
// Take out the "/.."
$relative_path = substr($relative_path, 0, $p) . substr($relative_path, $p+3);
// Find the next "/.."
$q = $p;
$p = strpos($relative_path, '/..', $q);
}
// Get the rest of the relative path.
$realpath .= substr($relative_path, $q);
return $realpath;
}
?>
php.netatjulian-lemburg.de
20-Jul-2005 03:55
20-Jul-2005 03:55
You have a realpath.
Now you want a htmlpath.
First Suggestion:
<?php
function htmlpath($relative_path) {
$realpath=realpath($relative_path);
$htmlpath=str_replace($_SERVER['DOCUMENT_ROOT'],'',$realpath);
return $htmlpath;
}
?>
But this does not work on some servers.
Second Suggestion:
<?php
function htmlpath($realpath) {
$i = substr_count($_ENV["SCRIPT_URL"],'/')."<br>";
$baserealpath=realpath(str_repeat('../',$i-1));
$htmlpath=str_replace($baserealpath,'',$realpath);
return $htmlpath;
}
?>
Lars Scheithauer <l dot scheithauer at gmx dot de>
08-Jun-2005 05:44
08-Jun-2005 05:44
This function is also nice to test for security-breaches. You can forbid the script to access files below a certain directory to prevent "../../../etc/shadow" and similar attacks:
<?php
// declare the basic directory for security reasons
// Please do NOT attach a "/"-suffix !
$basedir = '/var/www/cgi-bin/scriptfolder';
// compare the entered path with the basedir
$path_parts = pathinfo($_REQUEST['file_to_get']);
if (realpath($path_parts['dirname']) != $basedir) {
/* appropriate action against crack-attempt*/
die ('coding good - h4x1ng bad!');
}
?>
The url "script.php?file_to_get=../../../etc/shadow" will now result in an error.
pulstar at ig dot com dot br
20-Dec-2004 09:43
20-Dec-2004 09:43
Sometimes you may need to refer to the absolute path of a file in your website instead of a relative path, but the realpath() function returns the path relative to the server's filesystem, not a path relative to your website root directory.
For example, realpath() may return something like this:
/home/yoursite/public_html/dir1/file.ext
You can't use this in an HTML document, because the web server will not find the file. To do so, you can use:
<?php
function htmlpath($relative_path) {
$realpath=realpath($relative_path);
$htmlpath=str_replace($_SERVER['DOCUMENT_ROOT'],'',$realpath);
return $htmlpath;
}
echo '<img src="',htmlpath('../../relative/path/to/file.ext'),'" border=1>';
?>
It will return something like:
<img src="/dir1/relative/path/to/file.ext" border=1>
carlosreche at yahoo dot com
16-Dec-2004 11:52
16-Dec-2004 11:52
In my last function, it will always discard "../" if there are no more parent dirs to go back. But it's a mistake! For example, relative paths like "../../downloads" returns "downloads/", and it should return exactly the same entry (because parent directories for "downloads" may exist in this case). Well, I've corrected this bug. Now:
"C:/downloads/../../../" returns "C:/"
"downloads/../../../" returns "../../"
<?php
function real_path($path)
{
if ($path == "")
{
return false;
}
$path = trim(preg_replace("/\\\\/", "/", (string)$path));
if (!preg_match("/(\.\w{1,4})$/", $path) &&
!preg_match("/\?[^\\/]+$/", $path) &&
!preg_match("/\\/$/", $path))
{
$path .= '/';
}
$pattern = "/^(\\/|\w:\\/|https?:\\/\\/[^\\/]+\\/)?(.*)$/i";
preg_match_all($pattern, $path, $matches, PREG_SET_ORDER);
$path_tok_1 = $matches[0][1];
$path_tok_2 = $matches[0][2];
$path_tok_2 = preg_replace(
array("/^\\/+/", "/\\/+/"),
array("", "/"),
$path_tok_2);
$path_parts = explode("/", $path_tok_2);
$real_path_parts = array();
for ($i = 0, $real_path_parts = array(); $i < count($path_parts); $i++)
{
if ($path_parts[$i] == '.')
{
continue;
}
else if ($path_parts[$i] == '..')
{
if ( (isset($real_path_parts[0]) && $real_path_parts[0] != '..')
|| ($path_tok_1 != "") )
{
array_pop($real_path_parts);
continue;
}
}
array_push($real_path_parts, $path_parts[$i]);
}
return $path_tok_1 . implode('/', $real_path_parts);
}
?>
ash at spamless dot theleys dot net
19-Nov-2004 05:37
19-Nov-2004 05:37
sarizmendi is right, and this is very frustrating. I'm trying to use a script with a different virtual root, which process folders/contents. This works perfectly with asp's server.mappath() but realpath() fails, because it's mapping to the same doc root (C:\inetpub\wwwroot) when it should be from a different virtual path (i.e. D:\content). Although I could force this to the static path, I'm trying to use it with a $_GET, and this could point to any of a number of virtual roots.
ilgarm -at- azeronline.com
11-Mar-2004 07:43
11-Mar-2004 07:43
I've tested several examples given by other ppls but none were working, at least on windows. so I spent time and wrote my own function for realpath( ) replacement that will work with non-existing paths also.
Here it is. Please, check it, if you have time and let me know about the results. Thanks.
<?php
define( "_PL_OS_SEP", "/" );
define( "_CUR_OS", substr( php_uname( ), 0, 7 ) == "Windows" ? "Win" : "_Nix" );
function checkCurrentOS( $_OS )
{
if ( strcmp( $_OS, _CUR_OS ) == 0 ) {
return true;
}
return false;
}
function isRelative( $_dir )
{
if ( checkCurrentOS( "Win" ) ) {
return ( preg_match( "/^\w+:/", $_dir ) <= 0 );
}
else {
return ( preg_match( "/^\//", $_dir ) <= 0 );
}
}
function unifyPath( $_path )
{
if ( checkCurrentOS( "Win" ) ) {
return str_replace( "\\", _PL_OS_SEP, $_path );
}
return $_path;
}
function getRealpath( $_path )
{
/*
* This is the starting point of the system root.
* Left empty for UNIX based and Mac.
* For Windows this is drive letter and semicolon.
*/
$__path = $_path;
if ( isRelative( $_path ) ) {
$__curdir = unifyPath( realpath( "." ) . _PL_OS_SEP );
$__path = $__curdir . $__path;
}
$__startPoint = "";
if ( checkCurrentOS( "Win" ) ) {
list( $__startPoint, $__path ) = explode( ":", $__path, 2 );
$__startPoint .= ":";
}
# From now processing is the same for WIndows and Unix, and hopefully for others.
$__realparts = array( );
$__parts = explode( _PL_OS_SEP, $__path );
for ( $i = 0; $i < count( $__parts ); $i++ ) {
if ( strlen( $__parts[ $i ] ) == 0 || $__parts[ $i ] == "." ) {
continue;
}
if ( $__parts[ $i ] == ".." ) {
if ( count( $__realparts ) > 0 ) {
array_pop( $__realparts );
}
}
else {
array_push( $__realparts, $__parts[ $i ] );
}
}
return $__startPoint . _PL_OS_SEP . implode( _PL_OS_SEP, $__realparts );
}
echo "getRealpath ../../x: ". getRealpath( "../../x" ) . "<BR>\n";
echo "getRealpath ./../x: ". getRealpath( "./../x" ) . "<BR>\n";
echo "getRealpath x: ". getRealpath( "x" ) . "<BR>\n";
echo "getRealpath /../x: ". getRealpath( "/../x" ) . "<BR>\n";
echo "getRealpath d:/../../x: ". getRealpath( "d:/../../x" ) . "<BR>\n";
echo "getRealpath ./../xx/xxx/.////../yyy: ". getRealpath( "./../xx/xxx/.////../yyy" ) . "<BR>\n";
?>
eric at themepark dot com
18-Jul-2002 01:15
18-Jul-2002 01:15
note that realpath() will chop any trailing delimiter like \ or / ...don't forget to add it back on if you need it.
Eric Mueller - themepark.com
jemptyg at rwmc dot net
05-Jul-2001 10:38
05-Jul-2001 10:38
realpath() seems to be equivalent to ASP's Server.MapPath. On my Win2k box I have successfully used realpath() to give me the full path for a file outside of the document_root. This will be very useful in conjunction with is_dir and/or is_file, which require a full path.
jerome at dot451 dot com
28-Aug-2000 07:03
28-Aug-2000 07:03
mkdir (and realpath) did not work because i'd used virtual() function to replace server side include in my file.
And i've just seen that virtual() function changes the current directory ... that's why !
jerome ;)