source4/cluster/ctdb/common/ctdb.c

   1 /*
   2    ctdb main protocol code
   3
   4    Copyright (C) Andrew Tridgell  2006
   5
   6    This library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2 of the License, or (at your option) any later version.
  10
  11    This library 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 GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with this library; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21 #include "includes.h"
  22 #include "lib/tdb/include/tdb.h"
  23 #include "lib/events/events.h"
  24 #include "lib/util/dlinklist.h"
  25 #include "system/network.h"
  26 #include "system/filesys.h"
  27 #include "../include/ctdb_private.h"
  28
  29 /*
  30   choose the transport we will use
  31 */
  32 int ctdb_set_transport(struct ctdb_context *ctdb, const char *transport)
  33 {
  34         int ctdb_tcp_init(struct ctdb_context *ctdb);
  35
  36         if (strcmp(transport, "tcp") == 0) {
  37                 return ctdb_tcp_init(ctdb);
  38         }
  39         ctdb_set_error(ctdb, "Unknown transport '%s'\n", transport);
  40         return -1;
  41 }
  42
  43 /*
  44   set some ctdb flags
  45 */
  46 void ctdb_set_flags(struct ctdb_context *ctdb, unsigned flags)
  47 {
  48         ctdb->flags |= flags;
  49 }
  50
  51 /*
  52   set max acess count before a dmaster migration
  53 */
  54 void ctdb_set_max_lacount(struct ctdb_context *ctdb, unsigned count)
  55 {
  56         ctdb->max_lacount = count;
  57 }
  58
  59 /*
  60   add a node to the list of active nodes
  61 */
  62 static int ctdb_add_node(struct ctdb_context *ctdb, char *nstr)
  63 {
  64         struct ctdb_node *node, **nodep;
  65
  66         nodep = talloc_realloc(ctdb, ctdb->nodes, struct ctdb_node *, ctdb->num_nodes+1);
  67         CTDB_NO_MEMORY(ctdb, nodep);
  68
  69         ctdb->nodes = nodep;
  70         nodep = &ctdb->nodes[ctdb->num_nodes];
  71         (*nodep) = talloc_zero(ctdb->nodes, struct ctdb_node);
  72         CTDB_NO_MEMORY(ctdb, *nodep);
  73         node = *nodep;
  74
  75         if (ctdb_parse_address(ctdb, node, nstr, &node->address) != 0) {
  76                 return -1;
  77         }
  78         node->ctdb = ctdb;
  79         node->name = talloc_asprintf(node, "%s:%u",
  80                                      node->address.address,
  81                                      node->address.port);
  82         /* for now we just set the vnn to the line in the file - this
  83            will change! */
  84         node->vnn = ctdb->num_nodes;
  85
  86         if (ctdb->methods->add_node(node) != 0) {
  87                 talloc_free(node);
  88                 return -1;
  89         }
  90
  91         if (ctdb_same_address(&ctdb->address, &node->address)) {
  92                 ctdb->vnn = node->vnn;
  93         }
  94
  95         ctdb->num_nodes++;
  96
  97         return 0;
  98 }
  99
 100 /*
 101   setup the node list from a file
 102 */
 103 int ctdb_set_nlist(struct ctdb_context *ctdb, const char *nlist)
 104 {
 105         char **lines;
 106         int nlines;
 107         int i;
 108
 109         lines = file_lines_load(nlist, &nlines, ctdb);
 110         if (lines == NULL) {
 111                 ctdb_set_error(ctdb, "Failed to load nlist '%s'\n", nlist);
 112                 return -1;
 113         }
 114
 115         for (i=0;i<nlines;i++) {
 116                 if (ctdb_add_node(ctdb, lines[i]) != 0) {
 117                         talloc_free(lines);
 118                         return -1;
 119                 }
 120         }
 121
 122         talloc_free(lines);
 123         return 0;
 124 }
 125
 126 /*
 127   setup the local node address
 128 */
 129 int ctdb_set_address(struct ctdb_context *ctdb, const char *address)
 130 {
 131         if (ctdb_parse_address(ctdb, ctdb, address, &ctdb->address) != 0) {
 132                 return -1;
 133         }
 134
 135         ctdb->name = talloc_asprintf(ctdb, "%s:%u",
 136                                      ctdb->address.address,
 137                                      ctdb->address.port);
 138         return 0;
 139 }
 140
 141 /*
 142   add a node to the list of active nodes
 143 */
 144 int ctdb_set_call(struct ctdb_context *ctdb, ctdb_fn_t fn, int id)
 145 {
 146         struct ctdb_registered_call *call;
 147
 148         call = talloc(ctdb, struct ctdb_registered_call);
 149         call->fn = fn;
 150         call->id = id;
 151
 152         DLIST_ADD(ctdb->calls, call);
 153         return 0;
 154 }
 155
 156 /*
 157   return the vnn of this node
 158 */
 159 uint32_t ctdb_get_vnn(struct ctdb_context *ctdb)
 160 {
 161         return ctdb->vnn;
 162 }
 163
 164 /*
 165   return the number of nodes
 166 */
 167 uint32_t ctdb_get_num_nodes(struct ctdb_context *ctdb)
 168 {
 169         return ctdb->num_nodes;
 170 }
 171
 172
 173 /*
 174   start the protocol going
 175 */
 176 int ctdb_start(struct ctdb_context *ctdb)
 177 {
 178         return ctdb->methods->start(ctdb);
 179 }
 180
 181 /*
 182   called by the transport layer when a packet comes in
 183 */
 184 static void ctdb_recv_pkt(struct ctdb_context *ctdb, uint8_t *data, uint32_t length)
 185 {
 186         struct ctdb_req_header *hdr;
 187
 188         if (length < sizeof(*hdr)) {
 189                 ctdb_set_error(ctdb, "Bad packet length %d\n", length);
 190                 return;
 191         }
 192         hdr = (struct ctdb_req_header *)data;
 193         if (length != hdr->length) {
 194                 ctdb_set_error(ctdb, "Bad header length %d expected %d\n",
 195                                hdr->length, length);
 196                 return;
 197         }
 198
 199         switch (hdr->operation) {
 200         case CTDB_REQ_CALL:
 201                 ctdb_request_call(ctdb, hdr);
 202                 break;
 203
 204         case CTDB_REPLY_CALL:
 205                 ctdb_reply_call(ctdb, hdr);
 206                 break;
 207
 208         case CTDB_REPLY_ERROR:
 209                 ctdb_reply_error(ctdb, hdr);
 210                 break;
 211
 212         case CTDB_REPLY_REDIRECT:
 213                 ctdb_reply_redirect(ctdb, hdr);
 214                 break;
 215
 216         case CTDB_REQ_DMASTER:
 217                 ctdb_request_dmaster(ctdb, hdr);
 218                 break;
 219
 220         case CTDB_REPLY_DMASTER:
 221                 ctdb_reply_dmaster(ctdb, hdr);
 222                 break;
 223
 224         case CTDB_REQ_MESSAGE:
 225                 ctdb_request_message(ctdb, hdr);
 226                 break;
 227
 228         default:
 229                 printf("Packet with unknown operation %d\n", hdr->operation);
 230                 talloc_free(hdr);
 231                 break;
 232         }
 233 }
 234
 235 /*
 236   called by the transport layer when a node is dead
 237 */
 238 static void ctdb_node_dead(struct ctdb_node *node)
 239 {
 240         node->ctdb->num_connected--;
 241         printf("%s: node %s is dead: %d connected\n",
 242                node->ctdb->name, node->name, node->ctdb->num_connected);
 243 }
 244
 245 /*
 246   called by the transport layer when a node is connected
 247 */
 248 static void ctdb_node_connected(struct ctdb_node *node)
 249 {
 250         node->ctdb->num_connected++;
 251         printf("%s: connected to %s - %d connected\n",
 252                node->ctdb->name, node->name, node->ctdb->num_connected);
 253 }
 254
 255 /*
 256   wait for all nodes to be connected
 257 */
 258 void ctdb_connect_wait(struct ctdb_context *ctdb)
 259 {
 260         int expected = ctdb->num_nodes - 1;
 261         if (ctdb->flags & CTDB_FLAG_SELF_CONNECT) {
 262                 expected++;
 263         }
 264         while (ctdb->num_connected != expected) {
 265                 event_loop_once(ctdb->ev);
 266         }
 267 }
 268
 269 /*
 270   wait until we're the only node left
 271 */
 272 void ctdb_wait_loop(struct ctdb_context *ctdb)
 273 {
 274         int expected = 0;
 275         if (ctdb->flags & CTDB_FLAG_SELF_CONNECT) {
 276                 expected++;
 277         }
 278         while (ctdb->num_connected > expected) {
 279                 event_loop_once(ctdb->ev);
 280         }
 281 }
 282
 283
 284 /*
 285   queue a packet or die
 286 */
 287 void ctdb_queue_packet(struct ctdb_context *ctdb, struct ctdb_req_header *hdr)
 288 {
 289         struct ctdb_node *node;
 290         node = ctdb->nodes[hdr->destnode];
 291         if (ctdb->methods->queue_pkt(node, (uint8_t *)hdr, hdr->length) != 0) {
 292                 ctdb_fatal(ctdb, "Unable to queue packet\n");
 293         }
 294 }
 295
 296
 297 static const struct ctdb_upcalls ctdb_upcalls = {
 298         .recv_pkt       = ctdb_recv_pkt,
 299         .node_dead      = ctdb_node_dead,
 300         .node_connected = ctdb_node_connected
 301 };
 302
 303 /*
 304   initialise the ctdb daemon.
 305
 306   NOTE: In current code the daemon does not fork. This is for testing purposes only
 307   and to simplify the code.
 308 */
 309 struct ctdb_context *ctdb_init(struct event_context *ev)
 310 {
 311         struct ctdb_context *ctdb;
 312
 313         ctdb = talloc_zero(ev, struct ctdb_context);
 314         ctdb->ev = ev;
 315         ctdb->upcalls = &ctdb_upcalls;
 316         ctdb->idr = idr_init(ctdb);
 317         ctdb->max_lacount = CTDB_DEFAULT_MAX_LACOUNT;
 318
 319         return ctdb;
 320 }
 321