Function mynewt::kernel::os::os_mbuf_prepend_pullup

pub unsafe extern "C" fn os_mbuf_prepend_pullup(
    om: *mut os_mbuf, 
    len: u16
) -> *mut os_mbuf

Prepends a chunk of empty data to the specified mbuf chain and ensures the chunk is contiguous. If either operation fails, the specified mbuf chain is freed and NULL is returned.

• om: The mbuf chain to prepend to.
• len: The number of bytes to prepend and pullup.

Return: The modified mbuf on success; NULL on failure (and the mbuf chain is freed).