Added filters to image upload script

[donncha]

This patch adds two filters to the file wp-admin/image-uploading.php

1. Check for upload errors before upload - useful to check for file space for example.

2. Check file after uploading.

Functions for both filters should return true/message if an error so that first plugin integrates into current code logic, and functions can be shared.

98a99,101
> if( isset( $error ) == false )
>       $error = apply_filters( "check_uploaded_file", $error );
>
427c430,434
< <?php elseif ( $action = 'upload' ) : ?>
---
> <?php elseif ( $action = 'upload' ) :
>       if( apply_filters( "pre_upload_error", false ) == true ) {
>               ?><div class="center tip">Sorry, you have used your space allocation. Please delete some files to upload more files.</div><?php
>       } else {
> ?>
440a448
> <?php } ?>

[skeltoac]

Someone might develop a pre_upload_error filter for something other than checking for space. Shouldn't the text of the tip be the return value of the flunked filter? Subsequent filters should simply return any non-false initial value:

function my_pre_upload_filter( $value ) {
  if ( false !== $value )
    return $value
  // Do tests and return a true message or false
}

[Nazgul]

Is this one still valid with the recent upload changes?

[Nazgul]

This ticket has been dead for two years.

If somebody has any opinions about this issue, they can reopen it or create a new one.