eval, include and output buffering

**Chung Leong** · May 10 '07, 04:05 PM

Re: eval, include and output buffering

On May 10, 4:29 pm, "Jon Slaughter" <Jon_Slaugh...@ Hotmail.comwrot e:

I'm using eval to excute some mixed php and html code but I cannot debug it.
I am essentially using filegetcontents to load up a php/html file and then
inserting it into another php/html file and then using eval to execute the
final product.
>
If I were to use include and output buffering instead of filegetcontents
would it allow be to debug the code? (I have to capture the include so it
can be modified which is why I used filegetcontents and eval in the first
place).
>
essentially instead of something like eval(mod(filege tcontents()))
>
I would have
>
ob_start();
include $filename;
$contents = mod(ob_get_cont ents());
ob_end_clean();
>
As far as I can remember mod only modifies html code but I can't be
completely sure. In any case I'm not sure how the include eval the code when
its buffered as if its just the output or what? Right now everythign is
working fine and I don't want to screw it up but I'm kinda dragging my feet
because of the debugging issues.
>
Thanks,
Jon

An alternative to using eval() is to implement a stream wrapper, then
using include/require on a custom URL. What I would do is save the
generated content to a temporary file during debug so that you can
more easily see where an error occur.

See http://www.php.net/manual/en/ref.stream.php

**Jon Slaughter** · May 10 '07, 05:05 PM

Re: eval, include and output buffering

"Chung Leong" <chernyshevsky@ hotmail.comwrot e in message
news:1178812844 .248954.101410@ y5g2000hsa.goog legroups.com...

On May 10, 4:29 pm, "Jon Slaughter" <Jon_Slaugh...@ Hotmail.comwrot e:

>I'm using eval to excute some mixed php and html code but I cannot debug
>it.
>I am essentially using filegetcontents to load up a php/html file and
>then
>inserting it into another php/html file and then using eval to execute
>the
>final product.
>>
>If I were to use include and output buffering instead of filegetcontents
>would it allow be to debug the code? (I have to capture the include so it
>can be modified which is why I used filegetcontents and eval in the first
>place).
>>
>essentially instead of something like eval(mod(filege tcontents()))
>>
>I would have
>>
>ob_start();
>include $filename;
>$contents = mod(ob_get_cont ents());
>ob_end_clean() ;
>>
>As far as I can remember mod only modifies html code but I can't be
>completely sure. In any case I'm not sure how the include eval the code
>when
>its buffered as if its just the output or what? Right now everythign is
>working fine and I don't want to screw it up but I'm kinda dragging my
>feet
>because of the debugging issues.
>>
>Thanks,
>Jon

>
An alternative to using eval() is to implement a stream wrapper, then
using include/require on a custom URL. What I would do is save the
generated content to a temporary file during debug so that you can
more easily see where an error occur.
>
See http://www.php.net/manual/en/ref.stream.php
>

Ok, I'm not sure if I understand what you mean. Are you saying that I should
read one php statement at a time and evaluate the php statements?

That is, I might read the file into an object and then parse it one
statement at a time and eval each statement. This way I could step through
the code... not necessarily the best way but does let me debug my code.

The problem is, that in my code I do something like

eval('?>'.AddNa vToPage($MainPa ge));

Where $MainPage is just an html file that acts as a template(I probably
could have included it aftwards instead of the way I did it but I think its
probably to late to recode it at this point).

So when I debug the code I get to this line and then cannot debug whats
inside.

What is inside is what AddNavToPage does, which is inserts a php/html file
$mainpage into the template page to generate the total page.

Essentially AddNavToPage returns a mixed php/html that was stiched together
by 2 other pages.

I suppose I could save it to a temp file like you mentioned and then include
it and it should work?

that is, instead of the eval line I could do

if ($DEBUG)
{
file_put_conten ts($temp, AddNavToPage($M ainPage)));
include $temp;
}

(psuedo code)

I'll try that and see what happens,

Thanks,
Jon

**Jon Slaughter** · May 10 '07, 05:15 PM

Re: eval, include and output buffering

>

if ($DEBUG)
{
file_put_conten ts($temp, AddNavToPage($M ainPage)));
include $temp;
}
>
(psuedo code)
>

Ok, it works. Shows me all the html and stuff but I guess its better than
nothing.

Thanks,
Jon

**Chung Leong** · May 10 '07, 09:15 PM

Re: eval, include and output buffering

On May 10, 7:00 pm, "Jon Slaughter" <Jon_Slaugh...@ Hotmail.comwrot e:

"Chung Leong" <chernyshev...@ hotmail.comwrot e in message
>
news:1178812844 .248954.101410@ y5g2000hsa.goog legroups.com...
>
>
>
>
>

On May 10, 4:29 pm, "Jon Slaughter" <Jon_Slaugh...@ Hotmail.comwrot e:

I'm using eval to excute some mixed php and html code but I cannot debug
it.
I am essentially using filegetcontents to load up a php/html file and
then
inserting it into another php/html file and then using eval to execute
the
final product.

>

If I were to use include and output buffering instead of filegetcontents
would it allow be to debug the code? (I have to capture the include so it
can be modified which is why I used filegetcontents and eval in the first
place).

>

essentially instead of something like eval(mod(filege tcontents()))

>

I would have

>

ob_start();
include $filename;
$contents = mod(ob_get_cont ents());
ob_end_clean();

>

As far as I can remember mod only modifies html code but I can't be
completely sure. In any case I'm not sure how the include eval the code
when
its buffered as if its just the output or what? Right now everythign is
working fine and I don't want to screw it up but I'm kinda dragging my
feet
because of the debugging issues.

>

Thanks,
Jon

>

An alternative to using eval() is to implement a stream wrapper, then
using include/require on a custom URL. What I would do is save the
generated content to a temporary file during debug so that you can
more easily see where an error occur.

>

Seehttp://www.php.net/manual/en/ref.stream.php

>
Ok, I'm not sure if I understand what you mean. Are you saying that I should
read one php statement at a time and evaluate the php statements?
>
That is, I might read the file into an object and then parse it one
statement at a time and eval each statement. This way I could step through
the code... not necessarily the best way but does let me debug my code.
>
The problem is, that in my code I do something like
>
eval('?>'.AddNa vToPage($MainPa ge));
>
Where $MainPage is just an html file that acts as a template(I probably
could have included it aftwards instead of the way I did it but I think its
probably to late to recode it at this point).
>
So when I debug the code I get to this line and then cannot debug whats
inside.
>
What is inside is what AddNavToPage does, which is inserts a php/html file
$mainpage into the template page to generate the total page.
>
Essentially AddNavToPage returns a mixed php/html that was stiched together
by 2 other pages.
>
I suppose I could save it to a temp file like you mentioned and then include
it and it should work?
>
that is, instead of the eval line I could do
>
if ($DEBUG)
{
file_put_conten ts($temp, AddNavToPage($M ainPage)));
include $temp;
>
}
>
(psuedo code)
>
I'll try that and see what happens,
>
Thanks,
Jon- Hide quoted text -
>
- Show quoted text -

No, what I mean is you define a stream wrapper, so you can access the
code generated by your procedure as though it's a file. The wrapper
would look something like this:

class AddNavStream {
var $data;
var $position;

function stream_open($pa th, $mode, $options, &$opened_pat h) {
// extract necessary info from $path
$url = parse_url($path );

// get the contents of the file
$file1 = file_get_conten ts( ... );
$file2 = file_get_conten ts( ... );

// do something here to generate the code
// to be executed...

if(defined('DEB UG')) {
// save contents to temp file
}

// contents of the pseudo file
$this->data = $code;
$this->position = 0;

return true;
}

function stream_read($co unt)
{
$ret = substr($this->data, $this->position, $count);
$this->position += strlen($ret);
return $ret;
}

// other handlers
}

You then call stream_wrapper_ register() to register the wrapper:

stream_wrapper_ register("addna v", "AddNavStre am ");

After doing that you can then do an include like this:

include("addnav ://nav.php/contents.php");

The wrapper handlers in the AddNavStream class will be called to
handle the request, with stream_open() being the first. The effect of
this will be like saving the code in a file first, then including it.

eval, include and output buffering

eval, include and output buffering

Comment

Comment

Comment

Comment