Function riot_sys::gnrc_pktbuf_merge

pub unsafe extern "C" fn gnrc_pktbuf_merge(
    pkt: *mut gnrc_pktsnip_t
) -> c_int

@brief Merge pktsnip chain to single pktsnip.

Specifically it calls @ref gnrc_pktbuf_realloc_data() on @p pkt, then copies the data of all following packet snips into that reallocated space, and removes the packet snip the data was copied from afterwards.

Example

Input

                                                    buffer
+---------------------------+                      +------+
| size = 8                  | data       +-------->|      |
| type = NETTYPE_IPV6       |------------+         +------+
+---------------------------+                      .      .
      | next                                       .      .
      v                                            .      .
+---------------------------+                      +------+
| size = 40                 | data    +----------->|      |
| type = NETTYPE_UDP        |---------+            +------+
+---------------------------+                      .      .
      | next                                       .      .
      v
+---------------------------+                      +------+
| size = 14                 | data +-------------->|      |
| type = NETTYPE_UNDEF      |------+               +------+
+---------------------------+                      .      .

Output

                                                    buffer
+---------------------------+                      +------+
| size = 62                 | data       +-------->|      |
| type = NETTYPE_IPV6       |------------+         |      |
+---------------------------+                      |      |
                                                   |      |
                                                   |      |
                                                   |      |
                                                   +------+
                                                            .      .

@warning @p pkt needs to write protected before calling this function. @note Packets in receive order need to call @ref gnrc_pktbuf_reverse_snips() first to get the data in the correct order.

@param[in,out] pkt The snip to merge.

@return 0, on success @return ENOMEM, if no space is left in the packet buffer.