ctdb/client/client_connect.c

   1 /*
   2    CTDB client code
   3
   4    Copyright (C) Amitay Isaacs  2015
   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 "replace.h"
  21 #include "system/network.h"
  22 #include "system/filesys.h"
  23
  24 #include <talloc.h>
  25 #include <tevent.h>
  26 #include <tdb.h>
  27
  28 #include "common/reqid.h"
  29 #include "common/srvid.h"
  30 #include "common/comm.h"
  31 #include "common/logging.h"
  32
  33 #include "lib/util/tevent_unix.h"
  34 #include "lib/util/debug.h"
  35
  36 #include "protocol/protocol.h"
  37 #include "protocol/protocol_api.h"
  38
  39 #include "client/client_private.h"
  40 #include "client/client.h"
  41
  42 static int ctdb_client_connect(struct ctdb_client_context *client,
  43                                struct tevent_context *ev,
  44                                const char *sockpath);
  45
  46 static int ctdb_client_context_destructor(struct ctdb_client_context *client);
  47
  48 int ctdb_client_init(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
  49                      const char *sockpath, struct ctdb_client_context **out)
  50 {
  51         struct ctdb_client_context *client;
  52         int ret;
  53
  54         client = talloc_zero(mem_ctx, struct ctdb_client_context);
  55         if (client == NULL) {
  56                 DEBUG(DEBUG_ERR, (__location__ " memory allocation error\n"));
  57                 return ENOMEM;
  58         }
  59
  60         ret = reqid_init(client, INT_MAX-200, &client->idr);
  61         if (ret != 0) {
  62                 DEBUG(DEBUG_ERR, ("reqid_init() failed, ret=%d\n", ret));
  63                 talloc_free(client);
  64                 return ret;
  65         }
  66
  67         ret = srvid_init(client, &client->srv);
  68         if (ret != 0) {
  69                 DEBUG(DEBUG_ERR, ("srvid_init() failed, ret=%d\n", ret));
  70                 talloc_free(client);
  71                 return ret;
  72         }
  73
  74         client->fd = -1;
  75         client->pnn = CTDB_UNKNOWN_PNN;
  76
  77         ret = ctdb_client_connect(client, ev, sockpath);
  78         if (ret != 0) {
  79                 talloc_free(client);
  80                 return ret;
  81         }
  82
  83         talloc_set_destructor(client, ctdb_client_context_destructor);
  84
  85         *out = client;
  86         return 0;
  87 }
  88
  89 static int ctdb_client_context_destructor(struct ctdb_client_context *client)
  90 {
  91         if (client->fd != -1) {
  92                 close(client->fd);
  93                 client->fd = -1;
  94         }
  95         return 0;
  96 }
  97
  98 static void client_read_handler(uint8_t *buf, size_t buflen,
  99                                 void *private_data);
 100 static void client_dead_handler(void *private_data);
 101
 102 static int ctdb_client_connect(struct ctdb_client_context *client,
 103                                struct tevent_context *ev, const char *sockpath)
 104 {
 105         struct sockaddr_un addr;
 106         size_t len;
 107         int fd, ret;
 108
 109         if (sockpath == NULL) {
 110                 DEBUG(DEBUG_ERR, ("socket path cannot be NULL\n"));
 111                 return EINVAL;
 112         }
 113
 114         memset(&addr, 0, sizeof(addr));
 115         addr.sun_family = AF_UNIX;
 116         len = strlcpy(addr.sun_path, sockpath, sizeof(addr.sun_path));
 117         if (len != strlen(sockpath)) {
 118                 DEBUG(DEBUG_ERR, ("socket path too long, len=%zu\n",
 119                                   strlen(sockpath)));
 120                 return ENAMETOOLONG;
 121         }
 122
 123         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 124         if (fd == -1) {
 125                 ret = errno;
 126                 DEBUG(DEBUG_ERR, ("socket() failed, errno=%d\n", ret));
 127                 return ret;
 128         }
 129
 130         ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
 131         if (ret == -1) {
 132                 ret = errno;
 133                 DEBUG(DEBUG_ERR, ("connect() failed, errno=%d\n", ret));
 134                 close(fd);
 135                 return ret;
 136         }
 137         client->fd = fd;
 138
 139         ret = comm_setup(client, ev, fd, client_read_handler, client,
 140                          client_dead_handler, client, &client->comm);
 141         if (ret != 0) {
 142                 DEBUG(DEBUG_ERR, ("comm_setup() failed, ret=%d\n", ret));
 143                 close(fd);
 144                 client->fd = -1;
 145                 return ret;
 146         }
 147
 148         ret = ctdb_ctrl_get_pnn(client, ev, client, CTDB_CURRENT_NODE,
 149                                 tevent_timeval_zero(), &client->pnn);
 150         if (ret != 0) {
 151                 DEBUG(DEBUG_ERR, ("failed to get current node pnn\n"));
 152                 close(fd);
 153                 client->fd = -1;
 154                 TALLOC_FREE(client->comm);
 155                 return ret;
 156         }
 157
 158         return 0;
 159 }
 160
 161 static void client_read_handler(uint8_t *buf, size_t buflen,
 162                                 void *private_data)
 163 {
 164         struct ctdb_client_context *client = talloc_get_type_abort(
 165                 private_data, struct ctdb_client_context);
 166         struct ctdb_req_header hdr;
 167         int ret;
 168
 169         ret = ctdb_req_header_pull(discard_const(buf), buflen, &hdr);
 170         if (ret != 0) {
 171                 DEBUG(DEBUG_WARNING, ("invalid header, ret=%d\n", ret));
 172                 return;
 173         }
 174
 175         if (buflen != hdr.length) {
 176                 DEBUG(DEBUG_WARNING, ("packet size mismatch %zu != %d\n",
 177                                       buflen, hdr.length));
 178                 return;
 179         }
 180
 181         ret = ctdb_req_header_verify(&hdr, 0);
 182         if (ret != 0) {
 183                 DEBUG(DEBUG_WARNING, ("invalid header, ret=%d\n", ret));
 184                 return;
 185         }
 186
 187         switch (hdr.operation) {
 188         case CTDB_REPLY_CALL:
 189                 ctdb_client_reply_call(client, buf, buflen, hdr.reqid);
 190                 break;
 191
 192         case CTDB_REQ_MESSAGE:
 193                 ctdb_client_req_message(client, buf, buflen, hdr.reqid);
 194                 break;
 195
 196         case CTDB_REPLY_CONTROL:
 197                 ctdb_client_reply_control(client, buf, buflen, hdr.reqid);
 198                 break;
 199
 200         default:
 201                 break;
 202         }
 203 }
 204
 205 static void client_dead_handler(void *private_data)
 206 {
 207         struct ctdb_client_context *client = talloc_get_type_abort(
 208                 private_data, struct ctdb_client_context);
 209         ctdb_client_callback_func_t callback = client->callback;
 210         void *callback_data = client->private_data;
 211
 212         talloc_free(client);
 213         if (callback != NULL) {
 214                 callback(callback_data);
 215                 return;
 216         }
 217
 218         DEBUG(DEBUG_NOTICE, ("connection to daemon closed, exiting\n"));
 219         exit(1);
 220 }
 221
 222 void ctdb_client_set_disconnect_callback(struct ctdb_client_context *client,
 223                                          ctdb_client_callback_func_t callback,
 224                                          void *private_data)
 225 {
 226         client->callback = callback;
 227         client->private_data = private_data;
 228 }
 229
 230 uint32_t ctdb_client_pnn(struct ctdb_client_context *client)
 231 {
 232         return client->pnn;
 233 }
 234
 235 void ctdb_client_wait(struct tevent_context *ev, bool *done)
 236 {
 237         while (! (*done)) {
 238                 tevent_loop_once(ev);
 239         }
 240 }
 241
 242 struct ctdb_recovery_wait_state {
 243         struct tevent_context *ev;
 244         struct ctdb_client_context *client;
 245 };
 246
 247 static void ctdb_recovery_wait_retry(struct tevent_req *subreq);
 248
 249 struct tevent_req *ctdb_recovery_wait_send(TALLOC_CTX *mem_ctx,
 250                                            struct tevent_context *ev,
 251                                            struct ctdb_client_context *client)
 252 {
 253         struct tevent_req *req, *subreq;
 254         struct ctdb_recovery_wait_state *state;
 255         int recmode;
 256         int ret;
 257
 258         req = tevent_req_create(mem_ctx, &state,
 259                                 struct ctdb_recovery_wait_state);
 260         if (req == NULL) {
 261                 return NULL;
 262         }
 263
 264         state->ev = ev;
 265         state->client = client;
 266
 267         ret = ctdb_ctrl_get_recmode(client, ev, client, client->pnn,
 268                                     tevent_timeval_zero(), &recmode);
 269         if (ret != 0) {
 270                 tevent_req_error(req, ret);
 271                 return tevent_req_post(req, ev);
 272         }
 273
 274         if (recmode == CTDB_RECOVERY_NORMAL) {
 275                 tevent_req_done(req);
 276                 return tevent_req_post(req, ev);
 277         }
 278
 279         subreq = tevent_wakeup_send(state, ev,
 280                                     tevent_timeval_current_ofs(1, 0));
 281         if (tevent_req_nomem(subreq, req)) {
 282                 return tevent_req_post(req, ev);
 283         }
 284         tevent_req_set_callback(subreq, ctdb_recovery_wait_retry, req);
 285
 286         return req;
 287 }
 288
 289 static void ctdb_recovery_wait_retry(struct tevent_req *subreq)
 290 {
 291         struct tevent_req *req = tevent_req_callback_data(
 292                 subreq, struct tevent_req);
 293         struct ctdb_recovery_wait_state *state = tevent_req_data(
 294                 req, struct ctdb_recovery_wait_state);
 295         int ret, recmode;
 296         bool status;
 297
 298         status = tevent_wakeup_recv(subreq);
 299         TALLOC_FREE(subreq);
 300         if (! status) {
 301                 tevent_req_error(req, ENOMEM);
 302                 return;
 303         }
 304
 305         ret = ctdb_ctrl_get_recmode(state, state->ev, state->client,
 306                                     ctdb_client_pnn(state->client),
 307                                     tevent_timeval_zero(), &recmode);
 308         if (ret != 0) {
 309                 tevent_req_error(req, ret);
 310                 return;
 311         }
 312
 313         if (recmode == CTDB_RECOVERY_NORMAL) {
 314                 tevent_req_done(req);
 315                 return;
 316         }
 317
 318         subreq = tevent_wakeup_send(state, state->ev,
 319                                     tevent_timeval_current_ofs(1, 0));
 320         if (tevent_req_nomem(subreq, req)) {
 321                 return;
 322         }
 323         tevent_req_set_callback(subreq, ctdb_recovery_wait_retry, req);
 324 }
 325
 326 bool ctdb_recovery_wait_recv(struct tevent_req *req, int *perr)
 327 {
 328         int err;
 329
 330         if (tevent_req_is_unix_error(req, &err)) {
 331                 if (perr != NULL) {
 332                         *perr = err;
 333                 }
 334                 return false;
 335         }
 336
 337         return true;
 338 }