Osmocom Libraries » libosmocore

struct osmo_io_ops {
...
void (*read_cb)(struct osmo_io_fd *iofd, int res, struct msgb *msg);
...
void (*write_cb)(struct osmo_io_fd *iofd, int res,
                                 struct msgb *msg);
...
int (*segmentation_cb)(struct msgb *msg);

The segmentation_cb is missing the "struct osmo_io_fd *iofd" in front. This puts several limitations for future users of the cb API, since there's no way to access related objects like iofd (private_nr, data ptr, etc.), which in turn doesn't allow higher level APIs (such as osmo_stream) to provide its own wrapper API passing eg. osmo_stream_cli/srv as a first parameter.

That means there's no way to store inter-msg state which may be needed at some point for segmentation, which doesn't come initially from first msgb.

segmentation_cb was added in libosmocore d4d03705f90e4a346f21ee2f328348b9ba37a201, between release 1.8.0 and 1.9.0.

Relevant users of segmentation_cb outside libosmocore which could be affected are:

libosmo-netif.git:

libosmo-netif/src/stream_srv.c
977: *  \param[in] segmentation_cb Segmentation callback to be set */
978:void osmo_stream_srv_set_segmentation_cb(struct osmo_stream_srv *conn,
979:                                             osmo_stream_srv_segmentation_cb_t segmentation_cb)
988:    conn_ops.segmentation_cb = segmentation_cb;

libosmo-netif/src/stream_cli.c
110:    osmo_stream_cli_segmentation_cb_t segmentation_cb;
433:    cli->segmentation_cb = NULL;
490:    .segmentation_cb = NULL,
527:    .segmentation_cb = NULL,
663:static void configure_cli_segmentation_cb(struct osmo_stream_cli *cli,
664:                                              osmo_stream_cli_segmentation_cb_t segmentation_cb)
670:    client_ops.segmentation_cb = segmentation_cb;
676: *  \param[in] segmentation_cb Target segmentation callback
678:void osmo_stream_cli_set_segmentation_cb(struct osmo_stream_cli *cli,
679:                                             osmo_stream_cli_segmentation_cb_t segmentation_cb)
681:    cli->segmentation_cb = segmentation_cb;

libosmo-netif/src/ipa.c
411:int osmo_ipa_segmentation_cb(struct msgb *msg)

libosmo-netif/include/osmocom/netif/ipa.h
66:int osmo_ipa_segmentation_cb(struct msgb *msg);

libosmo-sccp.git:

libosmo-sccp/src/ss7_internal.h
41:int xua_tcp_segmentation_cb(struct msgb *msg);

libosmo-sccp/src/osmo_ss7_xua_srv.c
89:            osmo_stream_srv_set_segmentation_cb(srv, osmo_ipa_segmentation_cb);
96:                        osmo_stream_srv_set_segmentation_cb(srv, xua_tcp_segmentation_cb);
103:            osmo_stream_srv_set_segmentation_cb(srv, NULL);

libosmo-sccp/src/osmo_ss7_asp.c
652:                        osmo_stream_cli_set_segmentation_cb(asp->client, osmo_ipa_segmentation_cb);
657:                                osmo_stream_cli_set_segmentation_cb(asp->client, NULL);
660:                                osmo_stream_cli_set_segmentation_cb(asp->client, xua_tcp_segmentation_cb);
667:                        osmo_stream_cli_set_segmentation_cb(asp->client, NULL);
856:int xua_tcp_segmentation_cb(struct msgb *msg)

osmo-bsc.git:

osmo-bsc/src/osmo-bsc/cbsp_link.c
109:    osmo_stream_srv_set_segmentation_cb(srv, osmo_cbsp_segmentation_cb);
231:                        osmo_stream_cli_set_segmentation_cb(cbc->client.cli, osmo_cbsp_segmentation_cb);