ctdb/client/client_event.c

   1 /*
   2    Eventd client api
   3
   4    Copyright (C) Amitay Isaacs  2016
   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/filesys.h"
  22 #include "system/network.h"
  23
  24 #include <talloc.h>
  25 #include <tevent.h>
  26
  27 #include "lib/util/debug.h"
  28 #include "lib/util/tevent_unix.h"
  29
  30 #include "common/logging.h"
  31 #include "common/reqid.h"
  32 #include "common/comm.h"
  33
  34 #include "protocol/protocol_api.h"
  35
  36 #include "client/client.h"
  37
  38 struct ctdb_event_context {
  39         struct reqid_context *idr;
  40         struct comm_context *comm;
  41         int fd;
  42
  43         ctdb_client_callback_func_t callback;
  44         void *private_data;
  45 };
  46
  47 static int ctdb_event_connect(struct ctdb_event_context *eclient,
  48                               struct tevent_context *ev,
  49                               const char *sockpath);
  50
  51 static int ctdb_event_context_destructor(struct ctdb_event_context *eclient);
  52
  53 int ctdb_event_init(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
  54                     const char *sockpath, struct ctdb_event_context **out)
  55 {
  56         struct ctdb_event_context *eclient;
  57         int ret;
  58
  59         eclient = talloc_zero(mem_ctx, struct ctdb_event_context);
  60         if (eclient == NULL) {
  61                 DEBUG(DEBUG_ERR, (__location__ " memory allocation error\n"));
  62                 return ENOMEM;
  63         }
  64
  65         ret = reqid_init(eclient, INT_MAX-200, &eclient->idr);
  66         if (ret != 0) {
  67                 DEBUG(DEBUG_ERR, ("reqid_init() failed, ret=%d\n", ret));
  68                 talloc_free(eclient);
  69                 return ret;
  70         }
  71
  72         eclient->fd = -1;
  73
  74         ret = ctdb_event_connect(eclient, ev, sockpath);
  75         if (ret != 0) {
  76                 talloc_free(eclient);
  77                 return ret;
  78         }
  79
  80         talloc_set_destructor(eclient, ctdb_event_context_destructor);
  81
  82         *out = eclient;
  83         return 0;
  84 }
  85
  86 static int ctdb_event_context_destructor(struct ctdb_event_context *eclient)
  87 {
  88         if (eclient->fd != -1) {
  89                 close(eclient->fd);
  90                 eclient->fd = -1;
  91         }
  92         return 0;
  93 }
  94
  95 static void event_read_handler(uint8_t *buf, size_t buflen,
  96                                void *private_data);
  97 static void event_dead_handler(void *private_data);
  98
  99 static int ctdb_event_connect(struct ctdb_event_context *eclient,
 100                               struct tevent_context *ev, const char *sockpath)
 101 {
 102         struct sockaddr_un addr;
 103         size_t len;
 104         int fd, ret;
 105
 106         if (sockpath == NULL) {
 107                 DEBUG(DEBUG_ERR, ("socket path cannot be NULL\n"));
 108                 return EINVAL;
 109         }
 110
 111         memset(&addr, 0, sizeof(addr));
 112         addr.sun_family = AF_UNIX;
 113         len = strlcpy(addr.sun_path, sockpath, sizeof(addr.sun_path));
 114         if (len >= sizeof(addr.sun_path)) {
 115                 DEBUG(DEBUG_ERR, ("socket path too long, len=%zu\n",
 116                                   strlen(sockpath)));
 117                 return ENAMETOOLONG;
 118         }
 119
 120         fd = socket(AF_UNIX, SOCK_STREAM, 0);
 121         if (fd == -1) {
 122                 ret = errno;
 123                 DEBUG(DEBUG_ERR, ("socket() failed, errno=%d\n", ret));
 124                 return ret;
 125         }
 126
 127         ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
 128         if (ret == -1) {
 129                 ret = errno;
 130                 DEBUG(DEBUG_ERR, ("connect() failed, errno=%d\n", ret));
 131                 close(fd);
 132                 return ret;
 133         }
 134         eclient->fd = fd;
 135
 136         ret = comm_setup(eclient, ev, fd, event_read_handler, eclient,
 137                          event_dead_handler, eclient, &eclient->comm);
 138         if (ret != 0) {
 139                 DEBUG(DEBUG_ERR, ("comm_setup() failed, ret=%d\n", ret));
 140                 close(fd);
 141                 eclient->fd = -1;
 142                 return ret;
 143         }
 144
 145         return 0;
 146 }
 147
 148 static void ctdb_event_msg_reply(struct ctdb_event_context *eclient,
 149                                  uint8_t *buf, size_t buflen);
 150
 151 static void event_read_handler(uint8_t *buf, size_t buflen,
 152                                void *private_data)
 153 {
 154         struct ctdb_event_context *eclient = talloc_get_type_abort(
 155                 private_data, struct ctdb_event_context);
 156
 157         ctdb_event_msg_reply(eclient, buf, buflen);
 158 }
 159
 160 static void event_dead_handler(void *private_data)
 161 {
 162         struct ctdb_event_context *eclient = talloc_get_type_abort(
 163                 private_data, struct ctdb_event_context);
 164         ctdb_client_callback_func_t callback = eclient->callback;
 165         void *callback_data = eclient->private_data;
 166
 167         talloc_free(eclient);
 168         if (callback != NULL) {
 169                 callback(callback_data);
 170                 return;
 171         }
 172
 173         DEBUG(DEBUG_NOTICE, ("connection to daemon closed, exiting\n"));
 174         exit(1);
 175 }
 176
 177 void ctdb_event_set_disconnect_callback(struct ctdb_event_context *eclient,
 178                                         ctdb_client_callback_func_t callback,
 179                                         void *private_data)
 180 {
 181         eclient->callback = callback;
 182         eclient->private_data = private_data;
 183 }
 184
 185 /*
 186  * Handle eventd_request and eventd_reply
 187  */
 188
 189 struct ctdb_event_msg_state {
 190         struct ctdb_event_context *eclient;
 191
 192         uint32_t reqid;
 193         struct tevent_req *req;
 194         struct ctdb_event_reply *reply;
 195 };
 196
 197 static int ctdb_event_msg_state_destructor(struct ctdb_event_msg_state *state);
 198 static void ctdb_event_msg_done(struct tevent_req *subreq);
 199
 200 struct tevent_req *ctdb_event_msg_send(TALLOC_CTX *mem_ctx,
 201                                        struct tevent_context *ev,
 202                                        struct ctdb_event_context *eclient,
 203                                        struct ctdb_event_request *request)
 204 {
 205         struct tevent_req *req, *subreq;
 206         struct ctdb_event_msg_state *state;
 207         uint8_t *buf;
 208         size_t buflen;
 209         int ret;
 210
 211         req = tevent_req_create(mem_ctx, &state, struct ctdb_event_msg_state);
 212         if (req == NULL) {
 213                 return NULL;
 214         }
 215
 216         state->eclient = eclient;
 217
 218         state->reqid = reqid_new(eclient->idr, state);
 219         if (state->reqid == REQID_INVALID) {
 220                 talloc_free(req);
 221                 return NULL;
 222         }
 223         state->req = req;
 224
 225         talloc_set_destructor(state, ctdb_event_msg_state_destructor);
 226
 227         ctdb_event_header_fill(&request->header, state->reqid);
 228
 229         buflen = ctdb_event_request_len(request);
 230         buf = talloc_size(state, buflen);
 231         if (tevent_req_nomem(buf, req)) {
 232                 return tevent_req_post(req, ev);
 233         }
 234
 235         ret = ctdb_event_request_push(request, buf, &buflen);
 236         if (ret != 0) {
 237                 tevent_req_error(req, ret);
 238                 return tevent_req_post(req, ev);
 239         }
 240
 241         subreq = comm_write_send(state, ev, eclient->comm, buf, buflen);
 242         if (tevent_req_nomem(subreq, req)) {
 243                 return tevent_req_post(req, ev);
 244         }
 245         tevent_req_set_callback(subreq, ctdb_event_msg_done, req);
 246
 247         return req;
 248 }
 249
 250 static int ctdb_event_msg_state_destructor(struct ctdb_event_msg_state *state)
 251 {
 252         reqid_remove(state->eclient->idr, state->reqid);
 253         return 0;
 254 }
 255
 256 static void ctdb_event_msg_done(struct tevent_req *subreq)
 257 {
 258         struct tevent_req *req = tevent_req_callback_data(
 259                 subreq, struct tevent_req);
 260         int ret;
 261         bool status;
 262
 263         status = comm_write_recv(subreq, &ret);
 264         TALLOC_FREE(subreq);
 265         if (! status) {
 266                 tevent_req_error(req, ret);
 267                 return;
 268         }
 269
 270         /* Wait for the reply or timeout */
 271 }
 272
 273 static void ctdb_event_msg_reply(struct ctdb_event_context *eclient,
 274                                  uint8_t *buf, size_t buflen)
 275 {
 276         struct ctdb_event_reply *reply;
 277         struct ctdb_event_msg_state *state;
 278         int ret;
 279
 280         reply = talloc_zero(eclient, struct ctdb_event_reply);
 281         if (reply == NULL) {
 282                 D_WARNING("memory allocation error\n");
 283                 return;
 284         }
 285
 286         ret = ctdb_event_reply_pull(buf, buflen, reply, reply);
 287         if (ret != 0) {
 288                 D_WARNING("Invalid packet received, ret=%d\n", ret);
 289                 return;
 290         }
 291
 292         state = reqid_find(eclient->idr, reply->header.reqid,
 293                            struct ctdb_event_msg_state);
 294         if (state == NULL) {
 295                 return;
 296         }
 297
 298         if (reply->header.reqid != state->reqid) {
 299                 return;
 300         }
 301
 302         state->reply = talloc_steal(state, reply);
 303         tevent_req_done(state->req);
 304 }
 305
 306 bool ctdb_event_msg_recv(struct tevent_req *req, int *perr,
 307                          TALLOC_CTX *mem_ctx,
 308                          struct ctdb_event_reply **reply)
 309 {
 310         struct ctdb_event_msg_state *state = tevent_req_data(
 311                 req, struct ctdb_event_msg_state);
 312         int ret;
 313
 314         if (tevent_req_is_unix_error(req, &ret)) {
 315                 if (perr != NULL) {
 316                         *perr = ret;
 317                 }
 318                 return false;
 319         }
 320
 321         if (reply != NULL) {
 322                 *reply = talloc_steal(mem_ctx, state->reply);
 323         }
 324
 325         return true;
 326 }
 327
 328 /*
 329  * Run an event
 330  */
 331
 332 struct tevent_req *ctdb_event_run_send(TALLOC_CTX *mem_ctx,
 333                                        struct tevent_context *ev,
 334                                        struct ctdb_event_context *eclient,
 335                                        enum ctdb_event event,
 336                                        uint32_t timeout, const char *arg_str)
 337 {
 338         struct ctdb_event_request request;
 339         struct ctdb_event_request_run rdata;
 340
 341         rdata.event = event;
 342         rdata.timeout = timeout;
 343         rdata.arg_str = arg_str;
 344
 345         request.rdata.command = CTDB_EVENT_COMMAND_RUN;
 346         request.rdata.data.run = &rdata;
 347
 348         return ctdb_event_msg_send(mem_ctx, ev, eclient, &request);
 349 }
 350
 351 bool ctdb_event_run_recv(struct tevent_req *req, int *perr, int *result)
 352 {
 353         struct ctdb_event_reply *reply;
 354         int ret;
 355         bool status;
 356
 357         status = ctdb_event_msg_recv(req, &ret, req, &reply);
 358         if (! status) {
 359                 if (perr != NULL) {
 360                         *perr = ret;
 361                 }
 362                 return false;
 363         }
 364
 365         if (reply->rdata.command != CTDB_EVENT_COMMAND_RUN) {
 366                 if (perr != NULL) {
 367                         *perr = EPROTO;
 368                 }
 369                 talloc_free(reply);
 370                 return false;
 371         }
 372
 373         if (result != NULL) {
 374                 *result = reply->rdata.result;
 375         }
 376
 377         talloc_free(reply);
 378         return true;
 379 }
 380
 381 /*
 382  * Get event status
 383  */
 384
 385 struct tevent_req *ctdb_event_status_send(TALLOC_CTX *mem_ctx,
 386                                           struct tevent_context *ev,
 387                                           struct ctdb_event_context *eclient,
 388                                           enum ctdb_event event,
 389                                           enum ctdb_event_status_state state)
 390 {
 391         struct ctdb_event_request request;
 392         struct ctdb_event_request_status rdata;
 393
 394         rdata.event = event;
 395         rdata.state = state;
 396
 397         request.rdata.command = CTDB_EVENT_COMMAND_STATUS;
 398         request.rdata.data.status = &rdata;
 399
 400         return ctdb_event_msg_send(mem_ctx, ev, eclient, &request);
 401 }
 402
 403 bool ctdb_event_status_recv(struct tevent_req *req, int *perr,
 404                             int32_t *result, int *event_status,
 405                             TALLOC_CTX *mem_ctx,
 406                             struct ctdb_script_list **script_list)
 407 {
 408         struct ctdb_event_reply *reply;
 409         int ret;
 410         bool status;
 411
 412         status = ctdb_event_msg_recv(req, &ret, req, &reply);
 413         if (! status) {
 414                 if (perr != NULL) {
 415                         *perr = ret;
 416                 }
 417                 return false;
 418         }
 419
 420         if (reply->rdata.command != CTDB_EVENT_COMMAND_STATUS) {
 421                 if (perr != NULL) {
 422                         *perr = EPROTO;
 423                 }
 424                 talloc_free(reply);
 425                 return false;
 426         }
 427
 428         if (result != NULL) {
 429                 *result = reply->rdata.result;
 430         }
 431         if (event_status != NULL) {
 432                 *event_status = reply->rdata.data.status->status;
 433         }
 434         if (script_list != NULL) {
 435                 *script_list = talloc_steal(mem_ctx,
 436                                         reply->rdata.data.status->script_list);
 437         }
 438
 439         talloc_free(reply);
 440         return true;
 441 }
 442
 443 /*
 444  * Get script list
 445  */
 446
 447 struct tevent_req *ctdb_event_script_list_send(
 448                                         TALLOC_CTX *mem_ctx,
 449                                         struct tevent_context *ev,
 450                                         struct ctdb_event_context *eclient)
 451 {
 452         struct ctdb_event_request request;
 453
 454         request.rdata.command = CTDB_EVENT_COMMAND_SCRIPT_LIST;
 455
 456         return ctdb_event_msg_send(mem_ctx, ev, eclient, &request);
 457 }
 458
 459 bool ctdb_event_script_list_recv(struct tevent_req *req, int *perr,
 460                                  int32_t *result, TALLOC_CTX *mem_ctx,
 461                                  struct ctdb_script_list **script_list)
 462 {
 463         struct ctdb_event_reply *reply;
 464         int ret;
 465         bool status;
 466
 467         status = ctdb_event_msg_recv(req, &ret, req, &reply);
 468         if (! status) {
 469                 if (perr != NULL) {
 470                         *perr = ret;
 471                 }
 472                 return false;
 473         }
 474
 475         if (reply->rdata.command != CTDB_EVENT_COMMAND_SCRIPT_LIST) {
 476                 if (perr != NULL) {
 477                         *perr = EPROTO;
 478                 }
 479                 talloc_free(reply);
 480                 return false;
 481         }
 482
 483         if (result != NULL) {
 484                 *result = reply->rdata.result;
 485         }
 486         if (script_list != NULL) {
 487                 *script_list = talloc_steal(mem_ctx,
 488                                 reply->rdata.data.script_list->script_list);
 489         }
 490
 491         talloc_free(reply);
 492         return true;
 493 }
 494
 495 /*
 496  * Enable a script
 497  */
 498
 499 struct tevent_req *ctdb_event_script_enable_send(
 500                                         TALLOC_CTX *mem_ctx,
 501                                         struct tevent_context *ev,
 502                                         struct ctdb_event_context *eclient,
 503                                         const char *script_name)
 504 {
 505         struct ctdb_event_request request;
 506         struct ctdb_event_request_script_enable rdata;
 507
 508         rdata.script_name = script_name;
 509
 510         request.rdata.command = CTDB_EVENT_COMMAND_SCRIPT_ENABLE;
 511         request.rdata.data.script_enable = &rdata;
 512
 513         return ctdb_event_msg_send(mem_ctx, ev, eclient, &request);
 514 }
 515
 516 bool ctdb_event_script_enable_recv(struct tevent_req *req, int *perr,
 517                                    int *result)
 518 {
 519         struct ctdb_event_reply *reply;
 520         int ret;
 521         bool status;
 522
 523         status = ctdb_event_msg_recv(req, &ret, req, &reply);
 524         if (! status) {
 525                 if (perr != NULL) {
 526                         *perr = ret;
 527                 }
 528                 return false;
 529         }
 530
 531         if (reply->rdata.command != CTDB_EVENT_COMMAND_SCRIPT_ENABLE) {
 532                 if (perr != NULL) {
 533                         *perr = EPROTO;
 534                 }
 535                 talloc_free(reply);
 536                 return false;
 537         }
 538
 539         if (result != NULL) {
 540                 *result = reply->rdata.result;
 541         }
 542
 543         talloc_free(reply);
 544         return true;
 545 }
 546
 547 /*
 548  * Disable a script
 549  */
 550
 551 struct tevent_req *ctdb_event_script_disable_send(
 552                                         TALLOC_CTX *mem_ctx,
 553                                         struct tevent_context *ev,
 554                                         struct ctdb_event_context *eclient,
 555                                         const char *script_name)
 556 {
 557         struct ctdb_event_request request;
 558         struct ctdb_event_request_script_disable rdata;
 559
 560         rdata.script_name = script_name;
 561
 562         request.rdata.command = CTDB_EVENT_COMMAND_SCRIPT_DISABLE;
 563         request.rdata.data.script_disable = &rdata;
 564
 565         return ctdb_event_msg_send(mem_ctx, ev, eclient, &request);
 566 }
 567
 568 bool ctdb_event_script_disable_recv(struct tevent_req *req, int *perr,
 569                                     int *result)
 570 {
 571         struct ctdb_event_reply *reply;
 572         int ret;
 573         bool status;
 574
 575         status = ctdb_event_msg_recv(req, &ret, req, &reply);
 576         if (! status) {
 577                 if (perr != NULL) {
 578                         *perr = ret;
 579                 }
 580                 return false;
 581         }
 582
 583         if (reply->rdata.command != CTDB_EVENT_COMMAND_SCRIPT_DISABLE) {
 584                 if (perr != NULL) {
 585                         *perr = EPROTO;
 586                 }
 587                 talloc_free(reply);
 588                 return false;
 589         }
 590
 591         if (result != NULL) {
 592                 *result = reply->rdata.result;
 593         }
 594
 595         talloc_free(reply);
 596         return true;
 597 }