[SOLVED] Problem with file permissions in PHP on Linux

luismartin · 03-14-2012, 06:52 AM

I've implemented a code to sequentially copy, crop and resize an image to adjust it to a smaller size with different ratio.

Everything works correctly in the development server. However I have problems in the production server:

First of all, the code creates an exact copy of the file from the source to the destination. The copy works fine, and this is how it is created:

Code:

-rw-rw-rw- 1 www-data www-data 25256 2012-03-14 11:36 17-f07.jpg

Afterwards I added a chmod in order to give the image file total permissions

Code:

-rwxrwxrwx 1 www-data www-data 25256 2012-03-14 11:29 17-f07.jpg

The thing is that I can't edit the copied file once created, (with the same user www-data !! ). So there is an error when the code tries to crop or resize it subsequently.

Any help would be greatly appreciated.

adixon · 03-14-2012, 07:33 AM

Hey luismartin,
can you also post your php..
and are you creating a copy on server or elsewhere?

luismartin · 03-14-2012, 07:51 AM

Quote:

Originally Posted by adixon

Hey luismartin,
can you also post your php..
and are you creating a copy on server or elsewhere?

Hello adixon,

well the whole code involving this process would be too large, but this is a snippet:

PHP Code:



$source = config_item('document_root') . $srcSrc; 
$dest = config_item('document_root') . $srcDest; 
try { 
    if (! $this->_process_image($source, $sourceWidth, $sourceHeight, '90%', true, 'auto', false, 'thumb', $dest)) { // Make exact copy 
        throw new Exception("Error copying $source to $dest"); 
    } 
    if (! @chmod($dest, 0777)) { 
        throw new Exception('File permissions error. File cannot be manipulated.'); 
    } 
    if (! $this->_crop_image($dest, $x_axis, $y_axis, $finalWidth, '')) { // Crop image with the ratio obtained with the final dim 
        throw new Exception("Error cropping $dest"); 
    } 
    if (! $this->_process_image($dest, $destWidth, $destHeight, '90%', true, $master_axis, false, 'thumb', $dest)) { // Resize cropped image 
        throw new Exception("Error resizing cropped image $dest"); 
    } 
} 
catch(Exception $e) { 
    $error = $error . "\n" . $e->getMessage(); 
}

The error I get is:
"Error cropping /var/www/.../images/image_name.jpg"

adixon · 03-14-2012, 08:20 AM

what return code do you get from _crop_image?
also is it possible _process_image is not closing file resource appropriately..

luismartin · 03-14-2012, 06:09 PM

Quote:

Originally Posted by adixon

what return code do you get from _crop_image?
also is it possible _process_image is not closing file resource appropriately..

_crop_image returns true if the image is cropped, and false if there was a problem

I don't think _process_image is not closing the file resource properly. Both functions use a method of the CodeIgniter Image Manipulation class, which encapsulates everything. So it is not likely to be the problem...

dive · 03-14-2012, 06:32 PM

What are the ownership and permission of the folder containing the copied image?

(And why did you make the files +x? Not necessary.)

lithos · 03-14-2012, 08:00 PM

Why don't you try save the output image to different name and check if your production server has the same GD library as testing.
That way you could eliminate errors ...

easy php crop example and another.

luismartin · 03-15-2012, 04:58 AM

Hello dive and lithos.

dive: This is the list line corresponding to the containing folder:

Code:

drwxrwxrwx  2 desarrollo desarrollo  4096 2012-03-14 13:31 novedades

It's owned by another user ("desarrollo") but all the premissions are granted to everyone. I also added +x just in case. I'm not good on Linux yet.

lithos: you've been very helpful. I've echoed the phpinfo from both the development and production server and while the first one has gd enabled, the second one doesn't specify anything about gd. So is it possible that it has nothing to do with premissions but with the GD library? If the gd library is not installed, why did the copy work?

luismartin · 03-15-2012, 05:38 AM

Bingo!

It was due to the GD library which was not installed in production. Just installed it and everything works!

Thanks a lot everyone!