Update posts table in save_post action - php

Question

I am building mini-plugin, and i'm trying to update the wp_post table content of a post item.
My plugin add a input field in post edit.php page and changing the post_mime_type of the post in the database.
but since i am doing this in add_action( 'save_post', ..) i can`t use wp_update_post() because its doing a loop.
the relevante code is here:
add_action( 'save_post', 'member_manager_save_extras' );
function member_manager_save_extras($post_id){
if( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
return;
else if( !isset( $_POST['meta_box_nonce'] ) ||
!wp_verify_nonce( $_POST['meta_box_nonce'], 'my_meta_box_nonce' ) )
return;
else if( !current_user_can( 'edit_post' ) )
return $post_id;
else{
$post = get_post($id) ;
$post -> post_mime_type = "sss" ;
wp_update_post( (array) $post ) ;
}
}
so how can i update the post_mime_type in another way?

Answer 1

The most straight forward way to achieve this would be to remove the action and re-add it again, before and after you call wp_update_post, respectively:
add_action( 'save_post', 'member_manager_save_extras' );
function member_manager_save_extras($post_id){
if( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE )
return;
else if( !isset( $_POST['meta_box_nonce'] ) ||
!wp_verify_nonce( $_POST['meta_box_nonce'], 'my_meta_box_nonce' ) )
return;
else if( !current_user_can( 'edit_post' ) )
return $post_id;
else{
$post = get_post($id) ;
$post -> post_mime_type = "sss" ;
// Remove the action
remove_action( 'save_post', 'member_manager_save_extras' );
// Perform any update that uses the save_post hook
wp_update_post( (array) $post ) ;
// Add it back again
add_action( 'save_post', 'member_manager_save_extras' );
}
}