2 * Unix SMB/CIFS implementation.
3 * Samba internal messaging functions
4 * Copyright (C) 2017 by Volker Lendecke
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "lib/messages_ctdb.h"
22 #include "lib/util/server_id.h"
25 #include "lib/util/iov_buf.h"
26 #include "lib/messages_util.h"
27 #include "ctdbd_conn.h"
28 #include "lib/cluster_support.h"
30 struct messaging_ctdb_context;
33 * We can only have one tevent_fd per ctdb_context and per
34 * tevent_context. Maintain a list of registered tevent_contexts per
37 struct messaging_ctdb_fde_ev {
38 struct messaging_ctdb_fde_ev *prev, *next;
41 * Backreference to enable DLIST_REMOVE from our
42 * destructor. Also, set to NULL when the ctdb_context dies
43 * before the messaging_ctdb_fde_ev.
45 struct messaging_ctdb_context *ctx;
47 struct tevent_context *ev;
48 struct tevent_fd *fde;
51 struct messaging_ctdb_context {
52 struct ctdbd_connection *conn;
54 void (*recv_cb)(struct tevent_context *ev,
55 const uint8_t *msg, size_t msg_len,
56 int *fds, size_t num_fds,
58 void *recv_cb_private_data;
60 struct messaging_ctdb_fde_ev *fde_evs;
63 static int messaging_ctdb_recv(
64 struct tevent_context *ev,
65 uint32_t src_vnn, uint32_t dst_vnn, uint64_t dst_srvid,
66 const uint8_t *msg, size_t msg_len, void *private_data)
68 struct messaging_ctdb_context *state = talloc_get_type_abort(
69 private_data, struct messaging_ctdb_context);
71 state->recv_cb(ev, msg, msg_len, NULL, 0, state->recv_cb_private_data);
76 struct messaging_ctdb_context *global_ctdb_context;
78 int messaging_ctdb_init(const char *sockname, int timeout, uint64_t unique_id,
79 void (*recv_cb)(struct tevent_context *ev,
80 const uint8_t *msg, size_t msg_len,
81 int *fds, size_t num_fds,
85 struct messaging_ctdb_context *ctx;
88 if (global_ctdb_context != NULL) {
92 ctx = talloc_zero(NULL, struct messaging_ctdb_context);
96 ctx->recv_cb = recv_cb;
97 ctx->recv_cb_private_data = private_data;
99 ret = ctdbd_init_connection(ctx, sockname, timeout, &ctx->conn);
101 DBG_DEBUG("ctdbd_init_connection returned %s\n",
106 ret = register_with_ctdbd(ctx->conn, getpid(), messaging_ctdb_recv,
109 DBG_DEBUG("register_with_ctdbd returned %s (%d)\n",
114 ret = register_with_ctdbd(ctx->conn, unique_id, NULL, NULL);
116 DBG_DEBUG("register_with_ctdbd returned %s (%d)\n",
121 set_my_vnn(ctdbd_vnn(ctx->conn));
123 global_ctdb_context = ctx;
130 void messaging_ctdb_destroy(void)
132 TALLOC_FREE(global_ctdb_context);
135 int messaging_ctdb_send(uint32_t dst_vnn, uint64_t dst_srvid,
136 const struct iovec *iov, int iovlen)
138 struct messaging_ctdb_context *ctx = global_ctdb_context;
145 ret = ctdbd_messaging_send_iov(ctx->conn, dst_vnn, dst_srvid,
150 static void messaging_ctdb_read_handler(struct tevent_context *ev,
151 struct tevent_fd *fde,
155 struct messaging_ctdb_context *ctx = talloc_get_type_abort(
156 private_data, struct messaging_ctdb_context);
158 if ((flags & TEVENT_FD_READ) == 0) {
161 ctdbd_socket_readable(ev, ctx->conn);
164 struct messaging_ctdb_fde {
165 struct tevent_fd *fde;
168 static int messaging_ctdb_fde_ev_destructor(
169 struct messaging_ctdb_fde_ev *fde_ev)
171 if (fde_ev->ctx != NULL) {
172 DLIST_REMOVE(fde_ev->ctx->fde_evs, fde_ev);
179 * Reference counter for a struct tevent_fd messaging read event
180 * (with callback function) on a struct tevent_context registered
181 * on a messaging context.
183 * If we've already registered this struct tevent_context before
184 * (so already have a read event), just increase the reference count.
186 * Otherwise create a new struct tevent_fd messaging read event on the
187 * previously unseen struct tevent_context - this is what drives
188 * the message receive processing.
192 struct messaging_ctdb_fde *messaging_ctdb_register_tevent_context(
193 TALLOC_CTX *mem_ctx, struct tevent_context *ev)
195 struct messaging_ctdb_context *ctx = global_ctdb_context;
196 struct messaging_ctdb_fde_ev *fde_ev;
197 struct messaging_ctdb_fde *fde;
203 fde = talloc(mem_ctx, struct messaging_ctdb_fde);
208 for (fde_ev = ctx->fde_evs; fde_ev != NULL; fde_ev = fde_ev->next) {
209 if ((fde_ev->ev == ev) &&
210 (tevent_fd_get_flags(fde_ev->fde) != 0)) {
215 if (fde_ev == NULL) {
216 int sock = ctdbd_conn_get_fd(ctx->conn);
218 fde_ev = talloc(fde, struct messaging_ctdb_fde_ev);
219 if (fde_ev == NULL) {
222 fde_ev->fde = tevent_add_fd(
223 ev, fde_ev, sock, TEVENT_FD_READ,
224 messaging_ctdb_read_handler, ctx);
225 if (fde_ev->fde == NULL) {
231 DLIST_ADD(ctx->fde_evs, fde_ev);
232 talloc_set_destructor(
233 fde_ev, messaging_ctdb_fde_ev_destructor);
236 * Same trick as with tdb_wrap: The caller will never
237 * see the talloc_referenced object, the
238 * messaging_ctdb_fde_ev, so problems with
239 * talloc_unlink will not happen.
241 if (talloc_reference(fde, fde_ev) == NULL) {
247 fde->fde = fde_ev->fde;
251 bool messaging_ctdb_fde_active(struct messaging_ctdb_fde *fde)
258 flags = tevent_fd_get_flags(fde->fde);
262 struct ctdbd_connection *messaging_ctdb_connection(void)
264 if (global_ctdb_context == NULL) {
265 smb_panic("messaging not initialized\n");
267 return global_ctdb_context->conn;