X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=netlink.c;fp=netlink.c;h=a04e6c9a42d9235c8520899b5cd14974ed9b4816;hb=33ccd714ea9469b5b7d3b36bbe468ba1b0f31dfc;hp=0000000000000000000000000000000000000000;hpb=2095aa52444f9ab598475ddcf8ca1773a02f8e13;p=catta diff --git a/netlink.c b/netlink.c new file mode 100644 index 0000000..a04e6c9 --- /dev/null +++ b/netlink.c @@ -0,0 +1,154 @@ +#include +#include +#include + +#include "netlink.h" + +struct _flxNetlink { + GMainContext *context; + gint fd; + guint seq; + GPollFD poll_fd; + GSource *source; + void (*callback) (flxNetlink *nl, struct nlmsghdr *n, gpointer userdata); + gpointer userdata; + GSourceFuncs source_funcs; +}; + +static gboolean work(flxNetlink *nl) { + g_assert(nl); + + for (;;) { + guint8 replybuf[64*1024]; + ssize_t bytes; + struct nlmsghdr *p = (struct nlmsghdr *) replybuf; + + if ((bytes = recv(nl->fd, replybuf, sizeof(replybuf), MSG_DONTWAIT)) < 0) { + + if (errno == EAGAIN || errno == EINTR) + break; + + g_warning("NETLINK: recv() failed"); + return FALSE; + } + + if (nl->callback) { + for (; bytes > 0; p = NLMSG_NEXT(p, bytes)) { + if (!NLMSG_OK(p, bytes)) { + g_warning("NETLINK: packet truncated"); + return FALSE; + } + + nl->callback(nl, p, nl->userdata); + } + } + } + + return TRUE; +} + +static gboolean prepare_func(GSource *source, gint *timeout) { + g_assert(source); + g_assert(timeout); + + *timeout = -1; + return FALSE; +} + +static gboolean check_func(GSource *source) { + flxNetlink* nl; + g_assert(source); + + nl = *((flxNetlink**) (((guint8*) source) + sizeof(GSource))); + g_assert(nl); + + return nl->poll_fd.revents & G_IO_IN; +} + +static gboolean dispatch_func(GSource *source, GSourceFunc callback, gpointer user_data) { + flxNetlink* nl; + g_assert(source); + + nl = *((flxNetlink**) (((guint8*) source) + sizeof(GSource))); + g_assert(nl); + + return work(nl); +} + +flxNetlink *flx_netlink_new(GMainContext *context, guint32 groups, void (*cb) (flxNetlink *nl, struct nlmsghdr *n, gpointer userdata), gpointer userdata) { + int fd; + struct sockaddr_nl addr; + flxNetlink *nl; + + g_assert(context); + g_assert(cb); + + if ((fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE)) < 0) { + g_critical("NETLINK: socket(PF_NETLINK): %s", strerror(errno)); + return NULL; + } + + memset(&addr, 0, sizeof(addr)); + addr.nl_family = AF_NETLINK; + addr.nl_groups = groups; + addr.nl_pid = getpid(); + + if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { + close(fd); + g_critical("bind(): %s", strerror(errno)); + return NULL; + } + + nl = g_new(flxNetlink, 1); + nl->context = context; + g_main_context_ref(context); + nl->fd = fd; + nl->seq = 0; + nl->callback = cb; + nl->userdata = userdata; + + memset(&nl->source_funcs, 0, sizeof(nl->source_funcs)); + nl->source_funcs.prepare = prepare_func; + nl->source_funcs.check = check_func; + nl->source_funcs.dispatch = dispatch_func, + + nl->source = g_source_new(&nl->source_funcs, sizeof(GSource) + sizeof(flxNetlink*)); + *((flxNetlink**) (((guint8*) nl->source) + sizeof(GSource))) = nl; + + memset(&nl->poll_fd, 0, sizeof(GPollFD)); + nl->poll_fd.fd = fd; + nl->poll_fd.events = G_IO_IN|G_IO_ERR|G_IO_HUP; + g_source_add_poll(nl->source, &nl->poll_fd); + + g_source_attach(nl->source, nl->context); + + return nl; +} + +void flx_netlink_free(flxNetlink *nl) { + g_assert(nl); + + g_source_destroy(nl->source); + g_source_unref(nl->source); + g_main_context_unref(nl->context); + close(nl->fd); + g_free(nl); +} + +int flx_netlink_send(flxNetlink *nl, struct nlmsghdr *m, guint *ret_seq) { + g_assert(nl); + g_assert(m); + + m->nlmsg_seq = nl->seq++; + m->nlmsg_flags |= NLM_F_ACK; + + if (send(nl->fd, m, m->nlmsg_len, 0) < 0) { + g_warning("NETLINK: send(): %s\n", strerror(errno)); + return -1; + } + + if (ret_seq) + *ret_seq = m->nlmsg_seq; + + return 0; +}