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 #include "lib/util/iov_buf.h"
  24
  25 /*
  26  * It is not possible to include ctdb.h and tdb_compat.h (included via
  27  * some other include above) without warnings. This fixes those
  28  * warnings.
  29  */
  30
  31 #ifdef typesafe_cb
  32 #undef typesafe_cb
  33 #endif
  34
  35 #ifdef typesafe_cb_preargs
  36 #undef typesafe_cb_preargs
  37 #endif
  38
  39 #ifdef typesafe_cb_postargs
  40 #undef typesafe_cb_postargs
  41 #endif
  42
  43 #include "ctdb.h"
  44 #include "ctdb_private.h"
  45 #include "ctdbd_conn.h"
  46
  47
  48 struct messaging_ctdbd_context {
  49         struct ctdbd_connection *conn;
  50 };
  51
  52 /*
  53  * This is a Samba3 hack/optimization. Routines like process_exists need to
  54  * talk to ctdbd, and they don't get handed a messaging context.
  55  */
  56 static struct ctdbd_connection *global_ctdbd_connection;
  57 static int global_ctdb_connection_pid;
  58
  59 struct ctdbd_connection *messaging_ctdbd_connection(void)
  60 {
  61         if (!lp_clustering()) {
  62                 return NULL;
  63         }
  64
  65         if (global_ctdb_connection_pid == 0 &&
  66             global_ctdbd_connection == NULL) {
  67                 struct tevent_context *ev;
  68                 struct messaging_context *msg;
  69
  70                 ev = samba_tevent_context_init(NULL);
  71                 if (!ev) {
  72                         DEBUG(0,("samba_tevent_context_init failed\n"));
  73                 }
  74
  75                 msg = messaging_init(NULL, ev);
  76                 if (!msg) {
  77                         DEBUG(0,("messaging_init failed\n"));
  78                         return NULL;
  79                 }
  80         }
  81
  82         if (global_ctdb_connection_pid != getpid()) {
  83                 DEBUG(0,("messaging_ctdbd_connection():"
  84                          "valid for pid[%jd] but it's [%jd]\n",
  85                          (intmax_t)global_ctdb_connection_pid,
  86                          (intmax_t)getpid()));
  87                 smb_panic("messaging_ctdbd_connection() invalid process\n");
  88         }
  89
  90         return global_ctdbd_connection;
  91 }
  92
  93 static int messaging_ctdb_send(struct server_id src,
  94                                struct server_id pid, int msg_type,
  95                                const struct iovec *iov, int iovlen,
  96                                const int *fds, size_t num_fds,
  97                                struct messaging_backend *backend)
  98 {
  99         struct messaging_ctdbd_context *ctx = talloc_get_type_abort(
 100                 backend->private_data, struct messaging_ctdbd_context);
 101         struct messaging_rec msg;
 102         uint8_t *buf;
 103         ssize_t buflen;
 104         NTSTATUS status;
 105
 106         if (num_fds > 0) {
 107                 return ENOSYS;
 108         }
 109
 110         buflen = iov_buflen(iov, iovlen);
 111         if (buflen == -1) {
 112                 return EMSGSIZE;
 113         }
 114
 115         buf = talloc_array(talloc_tos(), uint8_t, buflen);
 116         if (buf == NULL) {
 117                 return ENOMEM;
 118         }
 119         iov_buf(iov, iovlen, buf, buflen);
 120
 121         msg = (struct messaging_rec) {
 122                 .msg_version    = MESSAGE_VERSION,
 123                 .msg_type       = msg_type,
 124                 .dest           = pid,
 125                 .src            = src,
 126                 .buf            = data_blob_const(buf, talloc_get_size(buf)),
 127         };
 128
 129         status = ctdbd_messaging_send(ctx->conn, pid.vnn, pid.pid, &msg);
 130
 131         TALLOC_FREE(buf);
 132
 133         if (NT_STATUS_IS_OK(status)) {
 134                 return 0;
 135         }
 136         return map_errno_from_nt_status(status);
 137 }
 138
 139 static int messaging_ctdbd_destructor(struct messaging_ctdbd_context *ctx)
 140 {
 141         /*
 142          * The global connection just went away
 143          */
 144         global_ctdb_connection_pid = 0;
 145         global_ctdbd_connection = NULL;
 146         return 0;
 147 }
 148
 149 NTSTATUS messaging_ctdbd_init(struct messaging_context *msg_ctx,
 150                               TALLOC_CTX *mem_ctx,
 151                               struct messaging_backend **presult)
 152 {
 153         struct messaging_backend *result;
 154         struct messaging_ctdbd_context *ctx;
 155         NTSTATUS status;
 156
 157         if (!(result = talloc(mem_ctx, struct messaging_backend))) {
 158                 DEBUG(0, ("talloc failed\n"));
 159                 return NT_STATUS_NO_MEMORY;
 160         }
 161
 162         if (!(ctx = talloc(result, struct messaging_ctdbd_context))) {
 163                 DEBUG(0, ("talloc failed\n"));
 164                 TALLOC_FREE(result);
 165                 return NT_STATUS_NO_MEMORY;
 166         }
 167
 168         status = ctdbd_messaging_connection(ctx, &ctx->conn);
 169
 170         if (!NT_STATUS_IS_OK(status)) {
 171                 DEBUG(10, ("ctdbd_messaging_connection failed: %s\n",
 172                            nt_errstr(status)));
 173                 TALLOC_FREE(result);
 174                 return status;
 175         }
 176
 177         status = ctdbd_register_msg_ctx(ctx->conn, msg_ctx);
 178
 179         if (!NT_STATUS_IS_OK(status)) {
 180                 DEBUG(10, ("ctdbd_register_msg_ctx failed: %s\n",
 181                            nt_errstr(status)));
 182                 TALLOC_FREE(result);
 183                 return status;
 184         }
 185
 186         global_ctdb_connection_pid = getpid();
 187         global_ctdbd_connection = ctx->conn;
 188         talloc_set_destructor(ctx, messaging_ctdbd_destructor);
 189
 190         set_my_vnn(ctdbd_vnn(ctx->conn));
 191
 192         result->send_fn = messaging_ctdb_send;
 193         result->private_data = (void *)ctx;
 194
 195         *presult = result;
 196         return NT_STATUS_OK;
 197 }