messaging3: Directly refer to messaging_dgm in messages.c

This removes the messaging_backend abstraction layer from messages_dgm.c. That
layer was introduced for ctdb and is still used there. But as the messaging_dgm
interface is very slim anyway, I don't think directly calling it is too bad.

Why this commit? It is another step towards making messages_dgm
independent of messages.[ch], thus it might become usable in other
contexts like ctdb and source4

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

3 files changed, 36 insertions, 64 deletions

diff --git a/source3/include/messages.h b/source3/include/messages.h
index 32c636f3fa..328161021f 100644
--- a/source3/include/messages.h
+++ b/source3/include/messages.h
@@ -73,21 +73,25 @@ struct messaging_backend {
 	void *private_data;
 };
 
+struct messaging_dgm_context;
 int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 		       struct tevent_context *ev,
 		       struct server_id pid,
-		       struct messaging_backend **presult,
 		       void (*recv_cb)(int msg_type,
 				       struct server_id src,
 				       struct server_id dst,
 				       const uint8_t *msg,
 				       size_t msg_len,
 				       void *private_data),
-		       void *recv_cb_private_data);
-int messaging_dgm_cleanup(struct messaging_context *msg_ctx, pid_t pid);
-int messaging_dgm_wipe(struct messaging_context *msg_ctx);
+		       void *recv_cb_private_data,
+		       struct messaging_dgm_context **pctx);
+int messaging_dgm_send(struct messaging_dgm_context *ctx,
+		       struct server_id src, struct server_id pid,
+		       int msg_type, const struct iovec *iov, int iovlen);
+int messaging_dgm_cleanup(struct messaging_dgm_context *ctx, pid_t pid);
+int messaging_dgm_wipe(struct messaging_dgm_context *ctx);
 void *messaging_dgm_register_tevent_context(TALLOC_CTX *mem_ctx,
-					    struct messaging_context *msg_ctx,
+					    struct messaging_dgm_context *ctx,
 					    struct tevent_context *ev);
 
 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
@@ -105,8 +109,6 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 struct server_id messaging_server_id(const struct messaging_context *msg_ctx);
 struct tevent_context *messaging_tevent_context(
 	struct messaging_context *msg_ctx);
-struct messaging_backend *messaging_local_backend(
-	struct messaging_context *msg_ctx);
 
 /*
  * re-init after a fork
diff --git a/source3/lib/messages.c b/source3/lib/messages.c
index 78a867adf4..18376bbe53 100644
--- a/source3/lib/messages.c
+++ b/source3/lib/messages.c
@@ -72,7 +72,8 @@ struct messaging_context {
 	struct tevent_req **waiters;
 	unsigned num_waiters;
 
-	struct messaging_backend *local;
+	struct messaging_dgm_context *local;
+
 	struct messaging_backend *remote;
 
 	bool *have_context;
@@ -245,7 +246,7 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 	ctx->have_context = &have_context;
 
 	ret = messaging_dgm_init(ctx, ctx->event_ctx, ctx->id,
-				 &ctx->local, messaging_recv_cb, ctx);
+				 messaging_recv_cb, ctx, &ctx->local);
 
 	if (ret != 0) {
 		DEBUG(2, ("messaging_dgm_init failed: %s\n", strerror(ret)));
@@ -304,8 +305,8 @@ NTSTATUS messaging_reinit(struct messaging_context *msg_ctx)
 	msg_ctx->id = procid_self();
 
 	ret = messaging_dgm_init(msg_ctx, msg_ctx->event_ctx,
-				 msg_ctx->id, &msg_ctx->local,
-				 messaging_recv_cb, msg_ctx);
+				 msg_ctx->id, messaging_recv_cb, msg_ctx,
+				 &msg_ctx->local);
 	if (ret != 0) {
 		DEBUG(0, ("messaging_dgm_init failed: %s\n", strerror(errno)));
 		return map_nt_error_from_unix(ret);
@@ -468,8 +469,8 @@ NTSTATUS messaging_send_iov(struct messaging_context *msg_ctx,
 		return NT_STATUS_OK;
 	}
 
-	ret = msg_ctx->local->send_fn(msg_ctx->id, server, msg_type,
-				      iov, iovlen, msg_ctx->local);
+	ret = messaging_dgm_send(msg_ctx->local, msg_ctx->id, server, msg_type,
+				 iov, iovlen);
 	if (ret != 0) {
 		return map_nt_error_from_unix(ret);
 	}
@@ -536,7 +537,7 @@ struct tevent_req *messaging_filtered_read_send(
 	tevent_req_defer_callback(req, state->ev);
 
 	state->tevent_handle = messaging_dgm_register_tevent_context(
-		state, msg_ctx, ev);
+		state, msg_ctx->local, ev);
 	if (tevent_req_nomem(state, req)) {
 		return tevent_req_post(req, ev);
 	}
@@ -899,7 +900,7 @@ static int mess_parent_dgm_cleanup(void *private_data)
 		private_data, struct messaging_context);
 	int ret;
 
-	ret = messaging_dgm_wipe(msg_ctx);
+	ret = messaging_dgm_wipe(msg_ctx->local);
 	DEBUG(10, ("messaging_dgm_wipe returned %s\n",
 		   ret ? strerror(ret) : "ok"));
 	return lp_parm_int(-1, "messaging", "messaging dgm cleanup interval",
@@ -933,20 +934,14 @@ int messaging_cleanup(struct messaging_context *msg_ctx, pid_t pid)
 	int ret;
 
 	if (pid == 0) {
-		ret = messaging_dgm_wipe(msg_ctx);
+		ret = messaging_dgm_wipe(msg_ctx->local);
 	} else {
-		ret = messaging_dgm_cleanup(msg_ctx, pid);
+		ret = messaging_dgm_cleanup(msg_ctx->local, pid);
 	}
 
 	return ret;
 }
 
-struct messaging_backend *messaging_local_backend(
-	struct messaging_context *msg_ctx)
-{
-	return msg_ctx->local;
-}
-
 struct tevent_context *messaging_tevent_context(
 	struct messaging_context *msg_ctx)
 {
diff --git a/source3/lib/messages_dgm.c b/source3/lib/messages_dgm.c
index 3fafebdbde..69d8677fbc 100644
--- a/source3/lib/messages_dgm.c
+++ b/source3/lib/messages_dgm.c
@@ -50,10 +50,6 @@ struct messaging_dgm_hdr {
 	struct server_id src;
 };
 
-static int messaging_dgm_send(struct server_id src,
-			      struct server_id pid, int msg_type,
-			      const struct iovec *iov, int iovlen,
-			      struct messaging_backend *backend);
 static void messaging_dgm_recv(struct unix_msg_ctx *ctx,
 			       uint8_t *msg, size_t msg_len,
 			       void *private_data);
@@ -174,16 +170,15 @@ static int messaging_dgm_lockfile_remove(TALLOC_CTX *tmp_ctx,
 int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 		       struct tevent_context *ev,
 		       struct server_id pid,
-		       struct messaging_backend **presult,
 		       void (*recv_cb)(int msg_type,
 				       struct server_id src,
 				       struct server_id dst,
 				       const uint8_t *msg,
 				       size_t msg_len,
 				       void *private_data),
-		       void *recv_cb_private_data)
+		       void *recv_cb_private_data,
+		       struct messaging_dgm_context **pctx)
 {
-	struct messaging_backend *result;
 	struct messaging_dgm_context *ctx;
 	int ret;
 	bool ok;
@@ -198,19 +193,11 @@ int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 		return errno;
 	}
 
-	result = talloc(mem_ctx, struct messaging_backend);
-	if (result == NULL) {
-		goto fail_nomem;
-	}
-	ctx = talloc_zero(result, struct messaging_dgm_context);
+	ctx = talloc_zero(mem_ctx, struct messaging_dgm_context);
 	if (ctx == NULL) {
 		goto fail_nomem;
 	}
-
-	result->private_data = ctx;
-	result->send_fn = messaging_dgm_send;
 	ctx->pid = pid;
-
 	ctx->recv_cb = recv_cb;
 	ctx->recv_cb_private_data = recv_cb_private_data;
 
@@ -228,7 +215,7 @@ int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 				sizeof(socket_address.sun_path),
 				"%s/%u", socket_dir, (unsigned)pid.pid);
 	if (sockname_len >= sizeof(socket_address.sun_path)) {
-		TALLOC_FREE(result);
+		TALLOC_FREE(ctx);
 		return ENAMETOOLONG;
 	}
 
@@ -239,7 +226,7 @@ int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 	if (ret != 0) {
 		DEBUG(1, ("%s: messaging_dgm_create_lockfile failed: %s\n",
 			  __func__, strerror(ret)));
-		TALLOC_FREE(result);
+		TALLOC_FREE(ctx);
 		return ret;
 	}
 
@@ -258,7 +245,7 @@ int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 					      0700);
 	if (!ok) {
 		DEBUG(1, ("Could not create socket directory\n"));
-		TALLOC_FREE(result);
+		TALLOC_FREE(ctx);
 		return EACCES;
 	}
 	TALLOC_FREE(socket_dir);
@@ -271,16 +258,16 @@ int messaging_dgm_init(TALLOC_CTX *mem_ctx,
 			    messaging_dgm_recv, ctx, &ctx->dgm_ctx);
 	if (ret != 0) {
 		DEBUG(1, ("unix_msg_init failed: %s\n", strerror(ret)));
-		TALLOC_FREE(result);
+		TALLOC_FREE(ctx);
 		return ret;
 	}
 	talloc_set_destructor(ctx, messaging_dgm_context_destructor);
 
-	*presult = result;
+	*pctx = ctx;
 	return 0;
 
 fail_nomem:
-	TALLOC_FREE(result);
+	TALLOC_FREE(ctx);
 	return ENOMEM;
 }
 
@@ -301,13 +288,10 @@ static int messaging_dgm_context_destructor(struct messaging_dgm_context *c)
 	return 0;
 }
 
-static int messaging_dgm_send(struct server_id src,
-			      struct server_id pid, int msg_type,
-			      const struct iovec *iov, int iovlen,
-			      struct messaging_backend *backend)
+int messaging_dgm_send(struct messaging_dgm_context *ctx,
+		       struct server_id src, struct server_id pid,
+		       int msg_type, const struct iovec *iov, int iovlen)
 {
-	struct messaging_dgm_context *ctx = talloc_get_type_abort(
-		backend->private_data, struct messaging_dgm_context);
 	struct messaging_dgm_hdr hdr;
 	struct iovec iov2[iovlen + 1];
 	struct server_id_buf idbuf;
@@ -371,11 +355,8 @@ static void messaging_dgm_recv(struct unix_msg_ctx *ctx,
 			 dgm_ctx->recv_cb_private_data);
 }
 
-int messaging_dgm_cleanup(struct messaging_context *msg_ctx, pid_t pid)
+int messaging_dgm_cleanup(struct messaging_dgm_context *ctx, pid_t pid)
 {
-	struct messaging_backend *be = messaging_local_backend(msg_ctx);
-	struct messaging_dgm_context *ctx = talloc_get_type_abort(
-		be->private_data, struct messaging_dgm_context);
 	char *lockfile_name, *socket_name;
 	int fd, ret;
 	struct flock lck = {};
@@ -424,11 +405,8 @@ int messaging_dgm_cleanup(struct messaging_context *msg_ctx, pid_t pid)
 	return 0;
 }
 
-int messaging_dgm_wipe(struct messaging_context *msg_ctx)
+int messaging_dgm_wipe(struct messaging_dgm_context *ctx)
 {
-	struct messaging_backend *be = messaging_local_backend(msg_ctx);
-	struct messaging_dgm_context *ctx = talloc_get_type_abort(
-		be->private_data, struct messaging_dgm_context);
 	char *msgdir_name;
 	DIR *msgdir;
 	struct dirent *dp;
@@ -472,7 +450,7 @@ int messaging_dgm_wipe(struct messaging_context *msg_ctx)
 			continue;
 		}
 
-		ret = messaging_dgm_cleanup(msg_ctx, pid);
+		ret = messaging_dgm_cleanup(ctx, pid);
 		DEBUG(10, ("messaging_dgm_cleanup(%lu) returned %s\n",
 			   pid, ret ? strerror(ret) : "ok"));
 	}
@@ -482,11 +460,8 @@ int messaging_dgm_wipe(struct messaging_context *msg_ctx)
 }
 
 void *messaging_dgm_register_tevent_context(TALLOC_CTX *mem_ctx,
-					    struct messaging_context *msg_ctx,
+					    struct messaging_dgm_context *ctx,
 					    struct tevent_context *ev)
 {
-	struct messaging_backend *be = messaging_local_backend(msg_ctx);
-	struct messaging_dgm_context *ctx = talloc_get_type_abort(
-		be->private_data, struct messaging_dgm_context);
 	return poll_funcs_tevent_register(mem_ctx, ctx->msg_callbacks, ev);
 }