Bad php behaviour with related paths

[Timothy Madden]

Hello all

I'm trying to include some files in an included file. Think of some scripts
like this

/index.php
/scripts/logging.php
/scripts/config.php
/scripts/db_access.php

index.php includes 'scripts/logging.php' and logging.php includes
'config.php' ºi 'db_access.php' .

My problem is that from within logging.php the php will try to include the
file '/config.php' and not '/scripts/config.php' because logging.php is
included in '/index.php' in the first place.

I would use absolute paths in the included file names, built with
$_SERVER['DOCUMENT_ROOT'], but I don't really know where my pages are on
the web server. I just know they are somewhere under DocumentRoot.

How can I write pages that can translate local paths to virtual paths and
that can be moved from one place to another in the virtual directory
hierarhy and still function corectly ?

How can I write pages that know about each other's URI's and that do not
care where they are placed on the webserver with respect to DocumentRoot ?


--
Thank you
Timothy Madden
Romania
------------------------------------
And I don't wanna miss a thing

[steve]

Re: Bad php behaviour with related paths

"Timothy Madden" wrote:[color=blue]
> Hello all
>
> I’m trying to include some files in an included file. Think of
> some scripts
> like this
>
> /index.php
> /scripts/logging.php
> /scripts/config.php
> /scripts/db_access.php
>
> index.php includes ’scripts/logging.php’ and logging.php
> includes
> ’config.php’ ºi ’db_access.php’ .
>
> My problem is that from within logging.php the php will try to[/color]
include[color=blue]
> the
> file ’/config.php’ and not
> ’/scripts/config.php’ because logging.php is
> included in ’/index.php’ in the first place.
>
> I would use absolute paths in the included file names, built with
> $_SERVER[’DOCUMENT_ROOT’], but I don’t really know
> where my pages are on
> the web server. I just know they are somewhere under DocumentRoot.
>
> How can I write pages that can translate local paths to virtual[/color]
paths[color=blue]
> and
> that can be moved from one place to another in the virtual[/color]
directory[color=blue]
> hierarhy and still function corectly ?
>
> How can I write pages that know about each other’s URI’s
> and that do not
> care where they are placed on the webserver with respect to
> DocumentRoot ?
>
>[/color]

Timothy, you don’t have to worry about where the files are on the
server. All you have to worry about is correctly setting up the paths
relative to the TOP calling script (in your case, where index.php
resides).

If you do it this way it will work:
in index.php ... include("./scripts/logging.php")
in logging.php ... include("./scripts/config.php")

You cannot say in logging.php ... include("config .php") since php
will look at the root to resolve this.

Hope this helps. This is one of the IMHO "weaknesses " of php, and
your situation comes up every day on usenet, so you are not alone.

--
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[Tony Marston]

Re: Bad php behaviour with related paths

Why don't you put 'scripts' in the include_path in your php.ini file? That
is what it is there for.

--
Tony Marston

http://www.tonymarston.net

"Timothy Madden" <batman@rmv.spa m.home.ro> wrote in message
news:uzdase2swa s7$.393lpn3qy5n l.dlg@40tude.ne t...[color=blue]
>
> Hello all
>
> I'm trying to include some files in an included file. Think of some[/color]
scripts[color=blue]
> like this
>
> /index.php
> /scripts/logging.php
> /scripts/config.php
> /scripts/db_access.php
>
> index.php includes 'scripts/logging.php' and logging.php includes
> 'config.php' ºi 'db_access.php' .
>
> My problem is that from within logging.php the php will try to include the
> file '/config.php' and not '/scripts/config.php' because logging.php is
> included in '/index.php' in the first place.
>
> I would use absolute paths in the included file names, built with
> $_SERVER['DOCUMENT_ROOT'], but I don't really know where my pages are on
> the web server. I just know they are somewhere under DocumentRoot.
>
> How can I write pages that can translate local paths to virtual paths and
> that can be moved from one place to another in the virtual directory
> hierarhy and still function corectly ?
>
> How can I write pages that know about each other's URI's and that do not
> care where they are placed on the webserver with respect to DocumentRoot ?
>
>
> --
> Thank you
> Timothy Madden
> Romania
> ------------------------------------
> And I don't wanna miss a thing[/color]

[Tim Tyler]

Re: Bad php behaviour with related paths

Timothy Madden <batman@rmv.spa m.home.ro> wrote or quoted:
[color=blue]
> I'm trying to include some files in an included file. Think of some scripts
> like this
>
> /index.php
> /scripts/logging.php
> /scripts/config.php
> /scripts/db_access.php
>
> index.php includes 'scripts/logging.php' and logging.php includes
> 'config.php' ?i 'db_access.php' .
>
> My problem is that from within logging.php the php will try to include the
> file '/config.php' and not '/scripts/config.php' because logging.php is
> included in '/index.php' in the first place.
>
> I would use absolute paths in the included file names, built with
> $_SERVER['DOCUMENT_ROOT'], but I don't really know where my pages are on
> the web server. I just know they are somewhere under DocumentRoot.
>
> How can I write pages that can translate local paths to virtual paths and
> that can be moved from one place to another in the virtual directory
> hierarhy and still function corectly ?
>
> How can I write pages that know about each other's URI's and that do not
> care where they are placed on the webserver with respect to DocumentRoot ?[/color]

You /could/ use this code:

<?php
function include_once_re lative($path) {
$from = realpath(dirnam e($_SERVER["SCRIPT_FILENAM E"]));
$to = realpath(dirnam e(__FILE__)."/".$path);

include_once(re lative_path($to ,$from));
}

function relative_path ($targetfile, $basedir = '.') {
$basedir = realpath ($basedir);
$targetfile = realpath ($targetfile);

// on windows, check that both paths are on the same drive
if (substr ($basedir, 0, 1) != substr ($targetfile, 0, 1)) {
return false;
}

// split each path into its directories
$base_parts = split ('\/', str_replace ('\\', '/', $basedir));
$target_parts = split ('\/', str_replace ('\\', '/', $targetfile));

// ensure that there are no empty elements at the end (c:\ would cause it)
for ($i = count($base_par ts) - 1; $i >= 0; $i--) {
if ($base_parts[$i] == '') {
unset ($base_parts[$i]);
} else {
break;
}
}
for ($i = count($target_p arts) - 1; $i >= 0; $i--) {
if ($target_parts[$i] == '') {
unset ($target_parts[$i]);
} else {
break;
}
}

// get rid of the common directories at the beginning of the paths
$common_count = 0;
for ($i = 0; $i < count($base_par ts); $i++) {
if ($target_parts[$i] == $base_parts[$i]) {
$common_count++ ;
} else {
break;
}
}
for ($i = 0; $i < $common_count; $i++) {
unset ($base_parts[$i]);
unset ($target_parts[$i]);
}

// build the resulting string
$cnt = count($base_par ts) - 1;
if ($cnt < 1) {
$cnt = 0;
}

return str_repeat ('../', $cnt).implode('/', $target_parts);
}

?>

Then calling "include_once_r elative" with relative paths would include
paths relative to the library code, not relative to the document.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

[Tim Tyler]

Re: Bad php behaviour with related paths

steve <UseLinkToEmail @dbforumz.com> wrote or quoted:[color=blue]
> "Timothy Madden" wrote:[/color]
[color=blue]
> Timothy, you don?t have to worry about where the files are on the
> server. All you have to worry about is correctly setting up the paths
> relative to the TOP calling script (in your case, where index.php
> resides).[/color]

That is not a feasible solution for library code which needs
to include other library code.

It results in the caller being required to manually include all the
needed library files, instead of just one of them (which includes all
the rest).
[color=blue]
> You cannot say in logging.php ... include("config .php") since php
> will look at the root to resolve this.
>
> Hope this helps. This is one of the IMHO "weaknesses " of php, and
> your situation comes up every day on usenet, so you are not alone.[/color]

It is indeed a disasterous design decision by the PHP authors :-(

There are work-arounds - but they are not neat - and PHP seems to badly
need an "include_relati ve" function built into its core.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

[Tim Tyler]

Re: Bad php behaviour with related paths

Tony Marston <tony@nospam.de mon.co.uk> wrote or quoted:
[color=blue]
> Why don't you put 'scripts' in the include_path in your php.ini file? That
> is what it is there for.[/color]

Modularily, encapsulation, not messing up the global namespace,
not requing users of your code to have access to the php.ini file -
there are *lots* of good reasons for not going down that path.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.

[Tony Marston]

Re: Bad php behaviour with related paths

If you don't have access to the php.ini file there are several ways to
change the settings:
(a) By using a .htaccess file (assuming you are using Apache)
(b) By using ini_set().

If I were wring software that needed to be initiated by include(), and this
software used include() on files in subdirectories, then I would write it so
that it worked.

If enough people requested an include_relativ e() function then I'm sure the
authors of PHP would add it in. But it seems that only a small number
*think* that it's necessary while the rest of us write code that doesn't
need it.

--
Tony Marston

http://www.tonymarston.net

"Tim Tyler" <tim@tt1lock.or g> wrote in message news:I2HExB.3CB @bath.ac.uk...[color=blue]
> Tony Marston <tony@nospam.de mon.co.uk> wrote or quoted:
>[color=green]
>> Why don't you put 'scripts' in the include_path in your php.ini file?
>> That
>> is what it is there for.[/color]
>
> Modularily, encapsulation, not messing up the global namespace,
> not requing users of your code to have access to the php.ini file -
> there are *lots* of good reasons for not going down that path.
> --
> __________
> |im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to reply.[/color]

[Timothy Madden]

Re: Bad php behaviour with related paths


"steve" <UseLinkToEmail @dbForumz.com> wrote in message
news:41126b80$1 _7@news.athenan ews.com...[color=blue]
> "Timothy Madden" wrote:[color=green]
> > Hello all
> >
> > I'm trying to include some files in an included file. Think of
> > some scripts
> > like this
> >
> > /index.php
> > /scripts/logging.php
> > /scripts/config.php
> > /scripts/db_access.php
> >
> > index.php includes 'scripts/logging.php' and logging.php
> > includes
> > 'config.php' ºi 'db_access.php' .
> >
> > My problem is that from within logging.php the php will try to[/color]
> include[color=green]
> > the
> > file ’/config.php’ and not
> > ’/scripts/config.php’ because logging.php is
> > included in ’/index.php’ in the first place.
> >
> > I would use absolute paths in the included file names, built with
> > $_SERVER[’DOCUMENT_ROOT’], but I don’t really know
> > where my pages are on
> > the web server. I just know they are somewhere under DocumentRoot.
> >
> > How can I write pages that can translate local paths to virtual[/color]
> paths[color=green]
> > and
> > that can be moved from one place to another in the virtual[/color]
> directory[color=green]
> > hierarhy and still function corectly ?
> >
> > How can I write pages that know about each other’s URI’s
> > and that do not
> > care where they are placed on the webserver with respect to
> > DocumentRoot ?
> >
> >[/color]
>
> Timothy, you don't have to worry about where the files are on the
> server. All you have to worry about is correctly setting up the paths
> relative to the TOP calling script (in your case, where index.php
> resides).
>
> If you do it this way it will work:
> in index.php ... include("./scripts/logging.php")
> in logging.php ... include("./scripts/config.php")
>
> You cannot say in logging.php ... include("config .php") since php
> will look at the root to resolve this.
>
> Hope this helps. This is one of the IMHO "weaknesses " of php, and
> your situation comes up every day on usenet, so you are not alone.
>[/color]
After a few moths ...
Time has passed, PHP 5 appeared, docs got a little better and now the
answer camed:

There is a constant named __FILE__ that is the name of the current
(included) file. With it I can get the base directory and compose the path
to other included files.

And __FILE__ was there since PHP 4.0, this was just a problem of
the quality of documentation for PHP (which I find to be very good
otherwise)

Timothy Madden
Romania
---------------------------------------------
And I don't wanna miss a thing
(remove 'rmv.spam' from my mail address)