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[%jd] but it's [%jd]\n",
  84                          (intmax_t)global_ctdb_connection_pid,
  85                          (intmax_t)getpid()));
  86                 smb_panic("messaging_ctdbd_connection() invalid process\n");
  87         }
  88
  89         return global_ctdbd_connection;
  90 }
  91
  92 static int messaging_ctdb_send(struct server_id src,
  93                                struct server_id pid, int msg_type,
  94                                const struct iovec *iov, int iovlen,
  95                                const int *fds, size_t num_fds,
  96                                struct messaging_backend *backend)
  97 {
  98         struct messaging_ctdbd_context *ctx = talloc_get_type_abort(
  99                 backend->private_data, struct messaging_ctdbd_context);
 100         struct messaging_rec msg;
 101         uint8_t *buf;
 102         NTSTATUS status;
 103
 104         if (num_fds > 0) {
 105                 return ENOSYS;
 106         }
 107
 108         buf = iov_buf(talloc_tos(), iov, iovlen);
 109         if (buf == NULL) {
 110                 return ENOMEM;
 111         }
 112
 113         msg = (struct messaging_rec) {
 114                 .msg_version    = MESSAGE_VERSION,
 115                 .msg_type       = msg_type,
 116                 .dest           = pid,
 117                 .src            = src,
 118                 .buf            = data_blob_const(buf, talloc_get_size(buf)),
 119         };
 120
 121         status = ctdbd_messaging_send(ctx->conn, pid.vnn, pid.pid, &msg);
 122
 123         TALLOC_FREE(buf);
 124
 125         if (NT_STATUS_IS_OK(status)) {
 126                 return 0;
 127         }
 128         return map_errno_from_nt_status(status);
 129 }
 130
 131 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 132 {
 133         /*
 134          * The global connection just went away
 135          */
 136         global_ctdb_connection_pid = 0;
 137         global_ctdbd_connection = NULL;
 138         return 0;
 139 }
 140
 141 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 142                               TALLOC_CTX *mem_ctx,
 143                               struct messaging_backend **presult)
 144 {
 145         struct messaging_backend *result;
 146         struct messaging_ctdbd_context *ctx;
 147         NTSTATUS status;
 148
 149         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 150                 DEBUG(0, ("talloc failed\n"));
 151                 return NT_STATUS_NO_MEMORY;
 152         }
 153
 154         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 155                 DEBUG(0, ("talloc failed\n"));
 156                 TALLOC_FREE(result);
 157                 return NT_STATUS_NO_MEMORY;
 158         }
 159
 160         status = ctdbd_messaging_connection(ctx, &ctx->conn);
 161
 162         if (!NT_STATUS_IS_OK(status)) {
 163                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 164                            nt_errstr(status)));
 165                 TALLOC_FREE(result);
 166                 return status;
 167         }
 168
 169         status = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 170
 171         if (!NT_STATUS_IS_OK(status)) {
 172                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 173                            nt_errstr(status)));
 174                 TALLOC_FREE(result);
 175                 return status;
 176         }
 177
 178         global_ctdb_connection_pid = getpid();
 179         global_ctdbd_connection = ctx->conn;
 180         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 181
 182         set_my_vnn(ctdbd_vnn(ctx->conn));
 183
 184         result->send_fn = messaging_ctdb_send;
 185         result->private_data = (void *)ctx;
 186
 187         *presult = result;
 188         return NT_STATUS_OK;
 189 }