wp-includes/ms-functions.php:2642Determines if there is any upload space left in the current blog's quota.
intfunction get_upload_space_available() { $allowed = get_space_allowed(); if ( $allowed < 0 ) { $allowed = 0; } $space_allowed = $allowed * MB_IN_BYTES; if ( get_site_option( 'upload_space_check_disabled' ) ) { return $space_allowed; } $space_used = get_space_used() * MB_IN_BYTES; if ( ( $space_allowed - $space_used ) <= 0 ) { return 0; } return $space_allowed - $space_used;}Introduced in 3.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/ms-functions.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.