source3/lib/messages_ctdbd.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba internal messaging functions
   4    Copyright (C) 2007 by Volker Lendecke
   5
   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.
  10
  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.
  15
  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/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "messages.h"
  22 #include "util_tdb.h"
  23
  24 /*
  25  * It is not possible to include ctdb.h and tdb_compat.h (included via
  26  * some other include above) without warnings. This fixes those
  27  * warnings.
  28  */
  29
  30 #ifdef typesafe_cb
  31 #undef typesafe_cb
  32 #endif
  33
  34 #ifdef typesafe_cb_preargs
  35 #undef typesafe_cb_preargs
  36 #endif
  37
  38 #ifdef typesafe_cb_postargs
  39 #undef typesafe_cb_postargs
  40 #endif
  41
  42 #include "ctdb.h"
  43 #include "ctdb_private.h"
  44 #include "ctdbd_conn.h"
  45
  46
  47 struct messaging_ctdbd_context {
  48         struct ctdbd_connection *conn;
  49 };
  50
  51 /*
  52  * This is a Samba3 hack/optimization. Routines like process_exists need to
  53  * talk to ctdbd, and they don't get handed a messaging context.
  54  */
  55 static struct ctdbd_connection *global_ctdbd_connection;
  56 static int global_ctdb_connection_pid;
  57
  58 struct ctdbd_connection *messaging_ctdbd_connection(void)
  59 {
  60         if (!lp_clustering()) {
  61                 return NULL;
  62         }
  63
  64         if (global_ctdb_connection_pid == 0 &&
  65             global_ctdbd_connection == NULL) {
  66                 struct tevent_context *ev;
  67                 struct messaging_context *msg;
  68
  69                 ev = samba_tevent_context_init(NULL);
  70                 if (!ev) {
  71                         DEBUG(0,("samba_tevent_context_init failed\n"));
  72                 }
  73
  74                 msg = messaging_init(NULL, ev);
  75                 if (!msg) {
  76                         DEBUG(0,("messaging_init failed\n"));
  77                         return NULL;
  78                 }
  79         }
  80
  81         if (global_ctdb_connection_pid != getpid()) {
  82                 DEBUG(0,("messaging_ctdbd_connection():"
  83                          "valid for pid[%d] but it's [%d]\n",
  84                          global_ctdb_connection_pid, getpid()));
  85                 smb_panic("messaging_ctdbd_connection() invalid process\n");
  86         }
  87
  88         return global_ctdbd_connection;
  89 }
  90
  91 static NTSTATUS messaging_ctdb_send(struct messaging_context *msg_ctx,
  92                                     struct server_id pid, int msg_type,
  93                                     const DATA_BLOB *data,
  94                                     struct messaging_backend *backend)
  95 {
  96         struct messaging_ctdbd_context *ctx = talloc_get_type_abort(
  97                 backend->private_data, struct messaging_ctdbd_context);
  98
  99         struct messaging_rec msg;
 100
 101         msg.msg_version = MESSAGE_VERSION;
 102         msg.msg_type    = msg_type;
 103         msg.dest        = pid;
 104         msg.src         = msg_ctx->id;
 105         msg.buf         = *data;
 106
 107         return ctdbd_messaging_send(ctx->conn, pid.vnn, pid.pid, &msg);
 108 }
 109
 110 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 111 {
 112         /*
 113          * The global connection just went away
 114          */
 115         global_ctdb_connection_pid = 0;
 116         global_ctdbd_connection = NULL;
 117         return 0;
 118 }
 119
 120 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 121                               TALLOC_CTX *mem_ctx,
 122                               struct messaging_backend **presult)
 123 {
 124         struct messaging_backend *result;
 125         struct messaging_ctdbd_context *ctx;
 126         NTSTATUS status;
 127
 128         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 129                 DEBUG(0, ("talloc failed\n"));
 130                 return NT_STATUS_NO_MEMORY;
 131         }
 132
 133         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 134                 DEBUG(0, ("talloc failed\n"));
 135                 TALLOC_FREE(result);
 136                 return NT_STATUS_NO_MEMORY;
 137         }
 138
 139         status = ctdbd_messaging_connection(ctx, &ctx->conn);
 140
 141         if (!NT_STATUS_IS_OK(status)) {
 142                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 143                            nt_errstr(status)));
 144                 TALLOC_FREE(result);
 145                 return status;
 146         }
 147
 148         status = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 149
 150         if (!NT_STATUS_IS_OK(status)) {
 151                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 152                            nt_errstr(status)));
 153                 TALLOC_FREE(result);
 154                 return status;
 155         }
 156
 157         global_ctdb_connection_pid = getpid();
 158         global_ctdbd_connection = ctx->conn;
 159         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 160
 161         set_my_vnn(ctdbd_vnn(ctx->conn));
 162
 163         result->send_fn = messaging_ctdb_send;
 164         result->private_data = (void *)ctx;
 165
 166         *presult = result;
 167         return NT_STATUS_OK;
 168 }