summaryrefslogtreecommitdiff
path: root/source3/lib/messages.c
diff options
context:
space:
mode:
Diffstat (limited to 'source3/lib/messages.c')
-rw-r--r--source3/lib/messages.c363
1 files changed, 363 insertions, 0 deletions
diff --git a/source3/lib/messages.c b/source3/lib/messages.c
new file mode 100644
index 0000000000..f5933cafdb
--- /dev/null
+++ b/source3/lib/messages.c
@@ -0,0 +1,363 @@
+/*
+ Unix SMB/CIFS implementation.
+ Samba internal messaging functions
+ Copyright (C) Andrew Tridgell 2000
+ Copyright (C) 2001 by Martin Pool
+ Copyright (C) 2002 by Jeremy Allison
+ Copyright (C) 2007 by Volker Lendecke
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ @defgroup messages Internal messaging framework
+ @{
+ @file messages.c
+
+ @brief Module for internal messaging between Samba daemons.
+
+ The idea is that if a part of Samba wants to do communication with
+ another Samba process then it will do a message_register() of a
+ dispatch function, and use message_send_pid() to send messages to
+ that process.
+
+ The dispatch function is given the pid of the sender, and it can
+ use that to reply by message_send_pid(). See ping_message() for a
+ simple example.
+
+ @caution Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
+
+ This system doesn't have any inherent size limitations but is not
+ very efficient for large messages or when messages are sent in very
+ quick succession.
+
+*/
+
+#include "includes.h"
+#include "librpc/gen_ndr/messaging.h"
+#include "librpc/gen_ndr/ndr_messaging.h"
+
+struct messaging_callback {
+ struct messaging_callback *prev, *next;
+ uint32 msg_type;
+ void (*fn)(struct messaging_context *msg, void *private_data,
+ uint32_t msg_type,
+ struct server_id server_id, DATA_BLOB *data);
+ void *private_data;
+};
+
+/****************************************************************************
+ A useful function for testing the message system.
+****************************************************************************/
+
+static void ping_message(struct messaging_context *msg_ctx,
+ void *private_data,
+ uint32_t msg_type,
+ struct server_id src,
+ DATA_BLOB *data)
+{
+ const char *msg = data->data ? (const char *)data->data : "none";
+
+ DEBUG(1,("INFO: Received PING message from PID %s [%s]\n",
+ procid_str_static(&src), msg));
+ messaging_send(msg_ctx, src, MSG_PONG, data);
+}
+
+/****************************************************************************
+ Register/replace a dispatch function for a particular message type.
+ JRA changed Dec 13 2006. Only one message handler now permitted per type.
+ *NOTE*: Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
+****************************************************************************/
+
+struct msg_all {
+ struct messaging_context *msg_ctx;
+ int msg_type;
+ uint32 msg_flag;
+ const void *buf;
+ size_t len;
+ int n_sent;
+};
+
+/****************************************************************************
+ Send one of the messages for the broadcast.
+****************************************************************************/
+
+static int traverse_fn(struct db_record *rec,
+ const struct connections_key *ckey,
+ const struct connections_data *crec,
+ void *state)
+{
+ struct msg_all *msg_all = (struct msg_all *)state;
+ NTSTATUS status;
+
+ if (crec->cnum != -1)
+ return 0;
+
+ /* Don't send if the receiver hasn't registered an interest. */
+
+ if(!(crec->bcast_msg_flags & msg_all->msg_flag))
+ return 0;
+
+ /* If the msg send fails because the pid was not found (i.e. smbd died),
+ * the msg has already been deleted from the messages.tdb.*/
+
+ status = messaging_send_buf(msg_all->msg_ctx,
+ crec->pid, msg_all->msg_type,
+ (uint8 *)msg_all->buf, msg_all->len);
+
+ if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
+
+ /* If the pid was not found delete the entry from connections.tdb */
+
+ DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
+ procid_str_static(&crec->pid), crec->cnum,
+ crec->servicename));
+
+ rec->delete_rec(rec);
+ }
+ msg_all->n_sent++;
+ return 0;
+}
+
+/**
+ * Send a message to all smbd processes.
+ *
+ * It isn't very efficient, but should be OK for the sorts of
+ * applications that use it. When we need efficient broadcast we can add
+ * it.
+ *
+ * @param n_sent Set to the number of messages sent. This should be
+ * equal to the number of processes, but be careful for races.
+ *
+ * @retval True for success.
+ **/
+bool message_send_all(struct messaging_context *msg_ctx,
+ int msg_type,
+ const void *buf, size_t len,
+ int *n_sent)
+{
+ struct msg_all msg_all;
+
+ msg_all.msg_type = msg_type;
+ if (msg_type < 1000)
+ msg_all.msg_flag = FLAG_MSG_GENERAL;
+ else if (msg_type > 1000 && msg_type < 2000)
+ msg_all.msg_flag = FLAG_MSG_NMBD;
+ else if (msg_type > 2000 && msg_type < 2100)
+ msg_all.msg_flag = FLAG_MSG_PRINT_NOTIFY;
+ else if (msg_type > 2100 && msg_type < 3000)
+ msg_all.msg_flag = FLAG_MSG_PRINT_GENERAL;
+ else if (msg_type > 3000 && msg_type < 4000)
+ msg_all.msg_flag = FLAG_MSG_SMBD;
+ else if (msg_type > 4000 && msg_type < 5000)
+ msg_all.msg_flag = FLAG_MSG_DBWRAP;
+ else
+ return False;
+
+ msg_all.buf = buf;
+ msg_all.len = len;
+ msg_all.n_sent = 0;
+ msg_all.msg_ctx = msg_ctx;
+
+ connections_forall(traverse_fn, &msg_all);
+ if (n_sent)
+ *n_sent = msg_all.n_sent;
+ return True;
+}
+
+struct event_context *messaging_event_context(struct messaging_context *msg_ctx)
+{
+ return msg_ctx->event_ctx;
+}
+
+struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
+ struct server_id server_id,
+ struct event_context *ev)
+{
+ struct messaging_context *ctx;
+ NTSTATUS status;
+
+ if (!(ctx = TALLOC_ZERO_P(mem_ctx, struct messaging_context))) {
+ return NULL;
+ }
+
+ ctx->id = server_id;
+ ctx->event_ctx = ev;
+
+ status = messaging_tdb_init(ctx, ctx, &ctx->local);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("messaging_tdb_init failed: %s\n",
+ nt_errstr(status)));
+ TALLOC_FREE(ctx);
+ return NULL;
+ }
+
+#ifdef CLUSTER_SUPPORT
+ if (lp_clustering()) {
+ status = messaging_ctdbd_init(ctx, ctx, &ctx->remote);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("messaging_ctdb_init failed: %s\n",
+ nt_errstr(status)));
+ TALLOC_FREE(ctx);
+ return NULL;
+ }
+ }
+#endif
+
+ messaging_register(ctx, NULL, MSG_PING, ping_message);
+
+ /* Register some debugging related messages */
+
+ register_msg_pool_usage(ctx);
+ register_dmalloc_msgs(ctx);
+ debug_register_msgs(ctx);
+
+ return ctx;
+}
+
+/*
+ * re-init after a fork
+ */
+NTSTATUS messaging_reinit(struct messaging_context *msg_ctx)
+{
+#ifdef CLUSTER_SUPPORT
+
+ TALLOC_FREE(msg_ctx->remote);
+
+ if (lp_clustering()) {
+ NTSTATUS status;
+
+ status = messaging_ctdbd_init(msg_ctx, msg_ctx,
+ &msg_ctx->remote);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("messaging_ctdb_init failed: %s\n",
+ nt_errstr(status)));
+ return status;
+ }
+ }
+
+#endif
+
+ return NT_STATUS_OK;
+}
+
+
+/*
+ * Register a dispatch function for a particular message type. Allow multiple
+ * registrants
+*/
+NTSTATUS messaging_register(struct messaging_context *msg_ctx,
+ void *private_data,
+ uint32_t msg_type,
+ void (*fn)(struct messaging_context *msg,
+ void *private_data,
+ uint32_t msg_type,
+ struct server_id server_id,
+ DATA_BLOB *data))
+{
+ struct messaging_callback *cb;
+
+ /*
+ * Only one callback per type
+ */
+
+ for (cb = msg_ctx->callbacks; cb != NULL; cb = cb->next) {
+ if (cb->msg_type == msg_type) {
+ cb->fn = fn;
+ cb->private_data = private_data;
+ return NT_STATUS_OK;
+ }
+ }
+
+ if (!(cb = talloc(msg_ctx, struct messaging_callback))) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ cb->msg_type = msg_type;
+ cb->fn = fn;
+ cb->private_data = private_data;
+
+ DLIST_ADD(msg_ctx->callbacks, cb);
+ return NT_STATUS_OK;
+}
+
+/*
+ De-register the function for a particular message type.
+*/
+void messaging_deregister(struct messaging_context *ctx, uint32_t msg_type,
+ void *private_data)
+{
+ struct messaging_callback *cb, *next;
+
+ for (cb = ctx->callbacks; cb; cb = next) {
+ next = cb->next;
+ if ((cb->msg_type == msg_type)
+ && (cb->private_data == private_data)) {
+ DLIST_REMOVE(ctx->callbacks, cb);
+ TALLOC_FREE(cb);
+ }
+ }
+}
+
+/*
+ Send a message to a particular server
+*/
+NTSTATUS messaging_send(struct messaging_context *msg_ctx,
+ struct server_id server, uint32_t msg_type,
+ const DATA_BLOB *data)
+{
+#ifdef CLUSTER_SUPPORT
+ if (!procid_is_local(&server)) {
+ return msg_ctx->remote->send_fn(msg_ctx, server,
+ msg_type, data,
+ msg_ctx->remote);
+ }
+#endif
+ return msg_ctx->local->send_fn(msg_ctx, server, msg_type, data,
+ msg_ctx->local);
+}
+
+NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
+ struct server_id server, uint32_t msg_type,
+ const uint8 *buf, size_t len)
+{
+ DATA_BLOB blob = data_blob_const(buf, len);
+ return messaging_send(msg_ctx, server, msg_type, &blob);
+}
+
+/*
+ Dispatch one messsaging_rec
+*/
+void messaging_dispatch_rec(struct messaging_context *msg_ctx,
+ struct messaging_rec *rec)
+{
+ struct messaging_callback *cb, *next;
+
+ for (cb = msg_ctx->callbacks; cb != NULL; cb = next) {
+ next = cb->next;
+ if (cb->msg_type == rec->msg_type) {
+ cb->fn(msg_ctx, cb->private_data, rec->msg_type,
+ rec->src, &rec->buf);
+ return;
+ }
+ }
+ return;
+}
+
+/** @} **/
generated by cgit (git 2.34.1) at 2025-02-08 21:50:29 +0000