There is one filter per option name; the $option in the filter name stands for the name (e.g. ‘sanitize_option_blogname‘, ‘sanitize_option_siteurl‘). You can use this filter to define a sanitizer for your own options. See the notes for sanitize_option() for a list of existing options.
Example Migrated from Codex:
To be more clear,
$original_valueholds the value before any sanitize_option_{$option} filter has been applied to the current option.So if
$valueis originally'My Value'and a filter with higher priority has sanitized it into'my_value', what we will receive is:$value = 'my_value'$option = 'the_option_name'
$original_value = 'My Value'
$original_valueis NOT the original option value, but the new option value before sanitization.