os_msys_get

struct os_mbuf *os_msys_get(uint16_t dsize, uint16_t leadingspace)

Retrieve an mbuf from the system mbuf pools with leadingspace bytes available in the mbuf.

Arguments

Arguments	Description
dsize	Minimum requested size of mbuf. Actual mbuf allocated may not accommodate dsize
leadingspace	Number of bytes for leading space in mbuf (space at start of mbuf)

Returned values

Pointer to mbuf or NULL if no mbufs were available.

Notes

As described in the overview section, os_msys_get() may return an mbuf that is smaller than dsize, meaning that the mbuf user data buffer does not have enough contiguous space to hold dsize bytes.

This API will not return an mbuf from a larger mbuf pool if the appropriate msys mbuf pool is empty. See the overview for more information.

Example

    struct os_mbuf *om;

    /* Allocate an mbuf with hopefully at least 100 bytes in its user data buffer */
    om = os_msys_get(100, 0);
    if (!om) {
        /* No mbufs available. */
        return -1;
    }
}