source3/smbd/notify_internal.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Andrew Tridgell 2006
   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 /*
  21   this is the change notify database. It implements mechanisms for
  22   storing current change notify waiters in a tdb, and checking if a
  23   given event matches any of the stored notify waiiters.
  24 */
  25
  26 #include "includes.h"
  27 #include "system/filesys.h"
  28 #include "librpc/gen_ndr/ndr_notify.h"
  29 #include "dbwrap/dbwrap.h"
  30 #include "dbwrap/dbwrap_open.h"
  31 #include "smbd/smbd.h"
  32 #include "messages.h"
  33 #include "lib/tdb_wrap/tdb_wrap.h"
  34 #include "util_tdb.h"
  35 #include "lib/param/param.h"
  36
  37 struct notify_context {
  38         struct db_context *db_recursive;
  39         struct db_context *db_onelevel;
  40         struct server_id server;
  41         struct messaging_context *messaging_ctx;
  42         struct notify_list *list;
  43         struct notify_array *array;
  44         int seqnum;
  45         struct sys_notify_context *sys_notify_ctx;
  46         TDB_DATA key;
  47 };
  48
  49
  50 struct notify_list {
  51         struct notify_list *next, *prev;
  52         void *private_data;
  53         void (*callback)(void *, const struct notify_event *);
  54         void *sys_notify_handle;
  55         int depth;
  56 };
  57
  58 #define NOTIFY_KEY "notify array"
  59
  60 #define NOTIFY_ENABLE           "notify:enable"
  61 #define NOTIFY_ENABLE_DEFAULT   True
  62
  63 static NTSTATUS notify_remove_all(struct notify_context *notify,
  64                                   const struct server_id *server);
  65 static void notify_handler(struct messaging_context *msg_ctx, void *private_data,
  66                            uint32_t msg_type, struct server_id server_id, DATA_BLOB *data);
  67
  68 /*
  69   destroy the notify context
  70 */
  71 static int notify_destructor(struct notify_context *notify)
  72 {
  73         messaging_deregister(notify->messaging_ctx, MSG_PVFS_NOTIFY, notify);
  74
  75         if (notify->list != NULL) {
  76                 notify_remove_all(notify, &notify->server);
  77         }
  78
  79         return 0;
  80 }
  81
  82 /*
  83   Open up the notify.tdb database. You should close it down using
  84   talloc_free(). We need the messaging_ctx to allow for notifications
  85   via internal messages
  86 */
  87 struct notify_context *notify_init(TALLOC_CTX *mem_ctx,
  88                                    struct messaging_context *messaging_ctx,
  89                                    struct event_context *ev)
  90 {
  91         struct notify_context *notify;
  92
  93         notify = talloc(mem_ctx, struct notify_context);
  94         if (notify == NULL) {
  95                 return NULL;
  96         }
  97
  98         notify->db_recursive = db_open(notify, lock_path("notify.tdb"),
  99                                        0, TDB_SEQNUM|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
 100                                        O_RDWR|O_CREAT, 0644,
 101                                        DBWRAP_LOCK_ORDER_2);
 102         if (notify->db_recursive == NULL) {
 103                 talloc_free(notify);
 104                 return NULL;
 105         }
 106
 107         notify->db_onelevel = db_open(notify, lock_path("notify_onelevel.tdb"),
 108                                       0, TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
 109                                       O_RDWR|O_CREAT, 0644,
 110                                       DBWRAP_LOCK_ORDER_2);
 111         if (notify->db_onelevel == NULL) {
 112                 talloc_free(notify);
 113                 return NULL;
 114         }
 115
 116         notify->server = messaging_server_id(messaging_ctx);
 117         notify->messaging_ctx = messaging_ctx;
 118         notify->list = NULL;
 119         notify->array = NULL;
 120         notify->seqnum = dbwrap_get_seqnum(notify->db_recursive);
 121         notify->key = string_term_tdb_data(NOTIFY_KEY);
 122
 123         talloc_set_destructor(notify, notify_destructor);
 124
 125         /* register with the messaging subsystem for the notify
 126            message type */
 127         messaging_register(notify->messaging_ctx, notify,
 128                            MSG_PVFS_NOTIFY, notify_handler);
 129
 130         notify->sys_notify_ctx = sys_notify_context_create(notify, ev);
 131
 132         return notify;
 133 }
 134
 135 bool notify_internal_parent_init(TALLOC_CTX *mem_ctx)
 136 {
 137         struct tdb_wrap *db1, *db2;
 138         struct loadparm_context *lp_ctx;
 139
 140         if (lp_clustering()) {
 141                 return true;
 142         }
 143
 144         lp_ctx = loadparm_init_s3(mem_ctx, loadparm_s3_context());
 145         if (lp_ctx == NULL) {
 146                 DEBUG(0, ("loadparm_init_s3 failed\n"));
 147                 return false;
 148         }
 149         /*
 150          * Open the tdbs in the parent process (smbd) so that our
 151          * CLEAR_IF_FIRST optimization in tdb_reopen_all can properly
 152          * work.
 153          */
 154
 155         db1 = tdb_wrap_open(mem_ctx, lock_path("notify.tdb"),
 156                             0, TDB_SEQNUM|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH,
 157                             O_RDWR|O_CREAT, 0644, lp_ctx);
 158         if (db1 == NULL) {
 159                 talloc_unlink(mem_ctx, lp_ctx);
 160                 DEBUG(1, ("could not open notify.tdb: %s\n", strerror(errno)));
 161                 return false;
 162         }
 163         db2 = tdb_wrap_open(mem_ctx, lock_path("notify_onelevel.tdb"),
 164                             0, TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH, O_RDWR|O_CREAT, 0644, lp_ctx);
 165         talloc_unlink(mem_ctx, lp_ctx);
 166         if (db2 == NULL) {
 167                 DEBUG(1, ("could not open notify_onelevel.tdb: %s\n",
 168                           strerror(errno)));
 169                 TALLOC_FREE(db1);
 170                 return false;
 171         }
 172         return true;
 173 }
 174
 175 /*
 176   lock and fetch the record
 177 */
 178 static NTSTATUS notify_fetch_locked(struct notify_context *notify, struct db_record **rec)
 179 {
 180         *rec = dbwrap_fetch_locked(notify->db_recursive, notify, notify->key);
 181         if (*rec == NULL) {
 182                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 183         }
 184         return NT_STATUS_OK;
 185 }
 186
 187 /*
 188   load the notify array
 189 */
 190 static NTSTATUS notify_load(struct notify_context *notify, struct db_record *rec)
 191 {
 192         TDB_DATA dbuf;
 193         DATA_BLOB blob;
 194         NTSTATUS status;
 195         int seqnum;
 196
 197         seqnum = dbwrap_get_seqnum(notify->db_recursive);
 198
 199         if (seqnum == notify->seqnum && notify->array != NULL) {
 200                 return NT_STATUS_OK;
 201         }
 202
 203         notify->seqnum = seqnum;
 204
 205         talloc_free(notify->array);
 206         notify->array = talloc_zero(notify, struct notify_array);
 207         NT_STATUS_HAVE_NO_MEMORY(notify->array);
 208
 209         if (!rec) {
 210                 status = dbwrap_fetch(notify->db_recursive, notify,
 211                                       notify->key, &dbuf);
 212                 if (!NT_STATUS_IS_OK(status)) {
 213                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
 214                 }
 215         } else {
 216                 dbuf = dbwrap_record_get_value(rec);
 217         }
 218
 219         blob.data = (uint8 *)dbuf.dptr;
 220         blob.length = dbuf.dsize;
 221
 222         status = NT_STATUS_OK;
 223         if (blob.length > 0) {
 224                 enum ndr_err_code ndr_err;
 225                 ndr_err = ndr_pull_struct_blob(&blob, notify->array, notify->array,
 226                                                (ndr_pull_flags_fn_t)ndr_pull_notify_array);
 227                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 228                         /* 1. log that we got a corrupt notify_array
 229                          * 2. clear the variable the garbage was stored into to not trip
 230                          *  over it next time this method is entered with the same seqnum
 231                          * 3. delete it from the database */
 232                         DEBUG(2, ("notify_array is corrupt, discarding it\n"));
 233
 234                         ZERO_STRUCTP(notify->array);
 235                         if (rec != NULL) {
 236                                 dbwrap_record_delete(rec);
 237                         }
 238
 239                 } else {
 240                         if (DEBUGLEVEL >= 10) {
 241                                 DEBUG(10, ("notify_load:\n"));
 242                                 NDR_PRINT_DEBUG(notify_array, notify->array);
 243                         }
 244                 }
 245         }
 246
 247
 248         if (!rec) {
 249                 talloc_free(dbuf.dptr);
 250         }
 251
 252         return status;
 253 }
 254
 255 /*
 256   compare notify entries for sorting
 257 */
 258 static int notify_compare(const struct notify_entry *e1, const struct notify_entry *e2)
 259 {
 260         return strcmp(e1->path, e2->path);
 261 }
 262
 263 /*
 264   save the notify array
 265 */
 266 static NTSTATUS notify_save(struct notify_context *notify, struct db_record *rec)
 267 {
 268         TDB_DATA dbuf;
 269         DATA_BLOB blob;
 270         NTSTATUS status;
 271         enum ndr_err_code ndr_err;
 272         TALLOC_CTX *tmp_ctx;
 273
 274         /* if possible, remove some depth arrays */
 275         while (notify->array->num_depths > 0 &&
 276                notify->array->depth[notify->array->num_depths-1].num_entries == 0) {
 277                 notify->array->num_depths--;
 278         }
 279
 280         /* we might just be able to delete the record */
 281         if (notify->array->num_depths == 0) {
 282                 return dbwrap_record_delete(rec);
 283         }
 284
 285         tmp_ctx = talloc_new(notify);
 286         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
 287
 288         ndr_err = ndr_push_struct_blob(&blob, tmp_ctx, notify->array,
 289                                       (ndr_push_flags_fn_t)ndr_push_notify_array);
 290         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 291                 talloc_free(tmp_ctx);
 292                 return ndr_map_error2ntstatus(ndr_err);
 293         }
 294
 295         if (DEBUGLEVEL >= 10) {
 296                 DEBUG(10, ("notify_save:\n"));
 297                 NDR_PRINT_DEBUG(notify_array, notify->array);
 298         }
 299
 300         dbuf.dptr = blob.data;
 301         dbuf.dsize = blob.length;
 302
 303         status = dbwrap_record_store(rec, dbuf, TDB_REPLACE);
 304         talloc_free(tmp_ctx);
 305
 306         return status;
 307 }
 308
 309
 310 /*
 311   handle incoming notify messages
 312 */
 313 static void notify_handler(struct messaging_context *msg_ctx, void *private_data,
 314                            uint32_t msg_type, struct server_id server_id, DATA_BLOB *data)
 315 {
 316         struct notify_context *notify = talloc_get_type(private_data, struct notify_context);
 317         enum ndr_err_code ndr_err;
 318         struct notify_event ev;
 319         TALLOC_CTX *tmp_ctx = talloc_new(notify);
 320         struct notify_list *listel;
 321
 322         if (tmp_ctx == NULL) {
 323                 return;
 324         }
 325
 326         ndr_err = ndr_pull_struct_blob(data, tmp_ctx, &ev,
 327                                        (ndr_pull_flags_fn_t)ndr_pull_notify_event);
 328         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 329                 talloc_free(tmp_ctx);
 330                 return;
 331         }
 332
 333         for (listel=notify->list;listel;listel=listel->next) {
 334                 if (listel->private_data == ev.private_data) {
 335                         listel->callback(listel->private_data, &ev);
 336                         break;
 337                 }
 338         }
 339
 340         talloc_free(tmp_ctx);
 341 }
 342
 343 /*
 344   callback from sys_notify telling us about changes from the OS
 345 */
 346 static void sys_notify_callback(struct sys_notify_context *ctx,
 347                                 void *ptr, struct notify_event *ev)
 348 {
 349         struct notify_list *listel = talloc_get_type(ptr, struct notify_list);
 350         ev->private_data = listel;
 351         DEBUG(10, ("sys_notify_callback called with action=%d, for %s\n",
 352                    ev->action, ev->path));
 353         listel->callback(listel->private_data, ev);
 354 }
 355
 356 /*
 357   add an entry to the notify array
 358 */
 359 static NTSTATUS notify_add_array(struct notify_context *notify, struct db_record *rec,
 360                                  struct notify_entry *e,
 361                                  void *private_data, int depth)
 362 {
 363         int i;
 364         struct notify_depth *d;
 365         struct notify_entry *ee;
 366
 367         /* possibly expand the depths array */
 368         if (depth >= notify->array->num_depths) {
 369                 d = talloc_realloc(notify->array, notify->array->depth,
 370                                    struct notify_depth, depth+1);
 371                 NT_STATUS_HAVE_NO_MEMORY(d);
 372                 for (i=notify->array->num_depths;i<=depth;i++) {
 373                         ZERO_STRUCT(d[i]);
 374                 }
 375                 notify->array->depth = d;
 376                 notify->array->num_depths = depth+1;
 377         }
 378         d = &notify->array->depth[depth];
 379
 380         /* expand the entries array */
 381         ee = talloc_realloc(notify->array->depth, d->entries, struct notify_entry,
 382                             d->num_entries+1);
 383         NT_STATUS_HAVE_NO_MEMORY(ee);
 384         d->entries = ee;
 385
 386         d->entries[d->num_entries] = *e;
 387         d->entries[d->num_entries].private_data = private_data;
 388         d->entries[d->num_entries].server = notify->server;
 389         d->entries[d->num_entries].path_len = strlen(e->path);
 390         d->num_entries++;
 391
 392         d->max_mask |= e->filter;
 393         d->max_mask_subdir |= e->subdir_filter;
 394
 395         TYPESAFE_QSORT(d->entries, d->num_entries, notify_compare);
 396
 397         /* recalculate the maximum masks */
 398         d->max_mask = 0;
 399         d->max_mask_subdir = 0;
 400
 401         for (i=0;i<d->num_entries;i++) {
 402                 d->max_mask |= d->entries[i].filter;
 403                 d->max_mask_subdir |= d->entries[i].subdir_filter;
 404         }
 405
 406         return notify_save(notify, rec);
 407 }
 408
 409 /*
 410   Add a non-recursive watch
 411 */
 412
 413 static void notify_add_onelevel(struct notify_context *notify,
 414                                 struct notify_entry *e, void *private_data)
 415 {
 416         struct notify_entry_array *array;
 417         struct db_record *rec;
 418         DATA_BLOB blob;
 419         TDB_DATA dbuf;
 420         TDB_DATA value;
 421         enum ndr_err_code ndr_err;
 422         NTSTATUS status;
 423
 424         array = talloc_zero(talloc_tos(), struct notify_entry_array);
 425         if (array == NULL) {
 426                 return;
 427         }
 428
 429         rec = dbwrap_fetch_locked(notify->db_onelevel, array,
 430                                   make_tdb_data((uint8_t *)&e->dir_id,
 431                                    sizeof(e->dir_id)));
 432         if (rec == NULL) {
 433                 DEBUG(10, ("notify_add_onelevel: fetch_locked for %s failed"
 434                            "\n", file_id_string_tos(&e->dir_id)));
 435                 TALLOC_FREE(array);
 436                 return;
 437         }
 438
 439         value = dbwrap_record_get_value(rec);
 440         blob.data = (uint8_t *)value.dptr;
 441         blob.length = value.dsize;
 442
 443         if (blob.length > 0) {
 444                 ndr_err = ndr_pull_struct_blob(&blob, array, array,
 445                         (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
 446                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 447                         DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
 448                                    ndr_errstr(ndr_err)));
 449                         TALLOC_FREE(array);
 450                         return;
 451                 }
 452                 if (DEBUGLEVEL >= 10) {
 453                         DEBUG(10, ("notify_add_onelevel:\n"));
 454                         NDR_PRINT_DEBUG(notify_entry_array, array);
 455                 }
 456         }
 457
 458         array->entries = talloc_realloc(array, array->entries,
 459                                         struct notify_entry,
 460                                         array->num_entries+1);
 461         if (array->entries == NULL) {
 462                 TALLOC_FREE(array);
 463                 return;
 464         }
 465         array->entries[array->num_entries] = *e;
 466         array->entries[array->num_entries].private_data = private_data;
 467         array->entries[array->num_entries].server = notify->server;
 468         array->num_entries += 1;
 469
 470         ndr_err = ndr_push_struct_blob(&blob, rec, array,
 471                 (ndr_push_flags_fn_t)ndr_push_notify_entry_array);
 472         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 473                 DEBUG(10, ("ndr_push_notify_entry_array failed: %s\n",
 474                            ndr_errstr(ndr_err)));
 475                 TALLOC_FREE(array);
 476                 return;
 477         }
 478
 479         if (DEBUGLEVEL >= 10) {
 480                 DEBUG(10, ("notify_add_onelevel:\n"));
 481                 NDR_PRINT_DEBUG(notify_entry_array, array);
 482         }
 483
 484         dbuf.dptr = blob.data;
 485         dbuf.dsize = blob.length;
 486
 487         status = dbwrap_record_store(rec, dbuf, TDB_REPLACE);
 488         TALLOC_FREE(array);
 489         if (!NT_STATUS_IS_OK(status)) {
 490                 DEBUG(10, ("notify_add_onelevel: store failed: %s\n",
 491                            nt_errstr(status)));
 492                 return;
 493         }
 494         e->filter = 0;
 495         return;
 496 }
 497
 498
 499 /*
 500   add a notify watch. This is called when a notify is first setup on a open
 501   directory handle.
 502 */
 503 NTSTATUS notify_add(struct notify_context *notify, connection_struct *conn,
 504                     struct notify_entry *e0,
 505                     void (*callback)(void *, const struct notify_event *),
 506                     void *private_data)
 507 {
 508         struct notify_entry e = *e0;
 509         NTSTATUS status;
 510         struct notify_list *listel;
 511         int depth;
 512
 513         /* see if change notify is enabled at all */
 514         if (notify == NULL) {
 515                 return NT_STATUS_NOT_IMPLEMENTED;
 516         }
 517
 518         depth = count_chars(e.path, '/');
 519
 520         listel = talloc_zero(notify, struct notify_list);
 521         if (listel == NULL) {
 522                 status = NT_STATUS_NO_MEMORY;
 523                 goto done;
 524         }
 525
 526         listel->private_data = private_data;
 527         listel->callback = callback;
 528         listel->depth = depth;
 529         DLIST_ADD(notify->list, listel);
 530
 531         /* ignore failures from sys_notify */
 532         if (notify->sys_notify_ctx != NULL) {
 533                 /*
 534                   this call will modify e.filter and e.subdir_filter
 535                   to remove bits handled by the backend
 536                 */
 537                 status = sys_notify_watch(notify->sys_notify_ctx, conn,
 538                                           &e, e.path,
 539                                           sys_notify_callback, listel,
 540                                           &listel->sys_notify_handle);
 541                 if (NT_STATUS_IS_OK(status)) {
 542                         talloc_steal(listel, listel->sys_notify_handle);
 543                 }
 544         }
 545
 546         if (e.filter != 0) {
 547                 notify_add_onelevel(notify, &e, private_data);
 548                 status = NT_STATUS_OK;
 549         }
 550
 551         /* if the system notify handler couldn't handle some of the
 552            filter bits, or couldn't handle a request for recursion
 553            then we need to install it in the array used for the
 554            intra-samba notify handling */
 555         if (e.filter != 0 || e.subdir_filter != 0) {
 556                 struct db_record *rec;
 557
 558                 status = notify_fetch_locked(notify, &rec);
 559                 if (!NT_STATUS_IS_OK(status)) {
 560                         goto done;
 561                 }
 562                 status = notify_load(notify, rec);
 563                 if (!NT_STATUS_IS_OK(status)) {
 564                         TALLOC_FREE(rec);
 565                         goto done;
 566                 }
 567                 status = notify_add_array(notify, rec, &e, private_data,
 568                                           depth);
 569                 TALLOC_FREE(rec);
 570         }
 571         status = NT_STATUS_OK;
 572 done:
 573         return status;
 574 }
 575
 576 NTSTATUS notify_remove_onelevel(struct notify_context *notify,
 577                                 const struct file_id *fid,
 578                                 void *private_data)
 579 {
 580         struct notify_entry_array *array;
 581         struct db_record *rec;
 582         DATA_BLOB blob;
 583         TDB_DATA dbuf;
 584         TDB_DATA value;
 585         enum ndr_err_code ndr_err;
 586         NTSTATUS status;
 587         int i;
 588
 589         if (notify == NULL) {
 590                 return NT_STATUS_NOT_IMPLEMENTED;
 591         }
 592
 593         array = talloc_zero(talloc_tos(), struct notify_entry_array);
 594         if (array == NULL) {
 595                 return NT_STATUS_NO_MEMORY;
 596         }
 597
 598         rec = dbwrap_fetch_locked(
 599                 notify->db_onelevel, array,
 600                 make_tdb_data((const uint8_t *)fid, sizeof(*fid)));
 601         if (rec == NULL) {
 602                 DEBUG(10, ("notify_remove_onelevel: fetch_locked for %s failed"
 603                            "\n", file_id_string_tos(fid)));
 604                 TALLOC_FREE(array);
 605                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
 606         }
 607
 608         value = dbwrap_record_get_value(rec);
 609         blob.data = (uint8_t *)value.dptr;
 610         blob.length = value.dsize;
 611
 612         if (blob.length > 0) {
 613                 ndr_err = ndr_pull_struct_blob(&blob, array, array,
 614                         (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
 615                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 616                         DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
 617                                    ndr_errstr(ndr_err)));
 618                         TALLOC_FREE(array);
 619                         return ndr_map_error2ntstatus(ndr_err);
 620                 }
 621                 if (DEBUGLEVEL >= 10) {
 622                         DEBUG(10, ("notify_remove_onelevel:\n"));
 623                         NDR_PRINT_DEBUG(notify_entry_array, array);
 624                 }
 625         }
 626
 627         for (i=0; i<array->num_entries; i++) {
 628                 if ((private_data == array->entries[i].private_data) &&
 629                     procid_equal(&notify->server, &array->entries[i].server)) {
 630                         break;
 631                 }
 632         }
 633
 634         if (i == array->num_entries) {
 635                 TALLOC_FREE(array);
 636                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 637         }
 638
 639         array->entries[i] = array->entries[array->num_entries-1];
 640         array->num_entries -= 1;
 641
 642         if (array->num_entries == 0) {
 643                 dbwrap_record_delete(rec);
 644                 TALLOC_FREE(array);
 645                 return NT_STATUS_OK;
 646         }
 647
 648         ndr_err = ndr_push_struct_blob(&blob, rec, array,
 649                 (ndr_push_flags_fn_t)ndr_push_notify_entry_array);
 650         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 651                 DEBUG(10, ("ndr_push_notify_entry_array failed: %s\n",
 652                            ndr_errstr(ndr_err)));
 653                 TALLOC_FREE(array);
 654                 return ndr_map_error2ntstatus(ndr_err);
 655         }
 656
 657         if (DEBUGLEVEL >= 10) {
 658                 DEBUG(10, ("notify_add_onelevel:\n"));
 659                 NDR_PRINT_DEBUG(notify_entry_array, array);
 660         }
 661
 662         dbuf.dptr = blob.data;
 663         dbuf.dsize = blob.length;
 664
 665         status = dbwrap_record_store(rec, dbuf, TDB_REPLACE);
 666         TALLOC_FREE(array);
 667         if (!NT_STATUS_IS_OK(status)) {
 668                 DEBUG(10, ("notify_add_onelevel: store failed: %s\n",
 669                            nt_errstr(status)));
 670                 return status;
 671         }
 672         return NT_STATUS_OK;
 673 }
 674
 675 /*
 676   remove a notify watch. Called when the directory handle is closed
 677 */
 678 NTSTATUS notify_remove(struct notify_context *notify, void *private_data)
 679 {
 680         NTSTATUS status;
 681         struct notify_list *listel;
 682         int i, depth;
 683         struct notify_depth *d;
 684         struct db_record *rec;
 685
 686         /* see if change notify is enabled at all */
 687         if (notify == NULL) {
 688                 return NT_STATUS_NOT_IMPLEMENTED;
 689         }
 690
 691         for (listel=notify->list;listel;listel=listel->next) {
 692                 if (listel->private_data == private_data) {
 693                         DLIST_REMOVE(notify->list, listel);
 694                         break;
 695                 }
 696         }
 697         if (listel == NULL) {
 698                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 699         }
 700
 701         depth = listel->depth;
 702
 703         talloc_free(listel);
 704
 705         status = notify_fetch_locked(notify, &rec);
 706         NT_STATUS_NOT_OK_RETURN(status);
 707
 708         status = notify_load(notify, rec);
 709         if (!NT_STATUS_IS_OK(status)) {
 710                 talloc_free(rec);
 711                 return status;
 712         }
 713
 714         if (depth >= notify->array->num_depths) {
 715                 talloc_free(rec);
 716                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 717         }
 718
 719         /* we only have to search at the depth of this element */
 720         d = &notify->array->depth[depth];
 721
 722         for (i=0;i<d->num_entries;i++) {
 723                 if (private_data == d->entries[i].private_data &&
 724                     procid_equal(&notify->server, &d->entries[i].server)) {
 725                         break;
 726                 }
 727         }
 728         if (i == d->num_entries) {
 729                 talloc_free(rec);
 730                 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
 731         }
 732
 733         if (i < d->num_entries-1) {
 734                 memmove(&d->entries[i], &d->entries[i+1],
 735                         sizeof(d->entries[i])*(d->num_entries-(i+1)));
 736         }
 737         d->num_entries--;
 738
 739         status = notify_save(notify, rec);
 740
 741         talloc_free(rec);
 742
 743         return status;
 744 }
 745
 746 /*
 747   remove all notify watches for a messaging server
 748 */
 749 static NTSTATUS notify_remove_all(struct notify_context *notify,
 750                                   const struct server_id *server)
 751 {
 752         NTSTATUS status;
 753         int i, depth, del_count=0;
 754         struct db_record *rec;
 755
 756         status = notify_fetch_locked(notify, &rec);
 757         NT_STATUS_NOT_OK_RETURN(status);
 758
 759         status = notify_load(notify, rec);
 760         if (!NT_STATUS_IS_OK(status)) {
 761                 talloc_free(rec);
 762                 return status;
 763         }
 764
 765         /* we have to search for all entries across all depths, looking for matches
 766            for the server id */
 767         for (depth=0;depth<notify->array->num_depths;depth++) {
 768                 struct notify_depth *d = &notify->array->depth[depth];
 769                 for (i=0;i<d->num_entries;i++) {
 770                         if (procid_equal(server, &d->entries[i].server)) {
 771                                 if (i < d->num_entries-1) {
 772                                         memmove(&d->entries[i], &d->entries[i+1],
 773                                                 sizeof(d->entries[i])*(d->num_entries-(i+1)));
 774                                 }
 775                                 i--;
 776                                 d->num_entries--;
 777                                 del_count++;
 778                         }
 779                 }
 780         }
 781
 782         if (del_count > 0) {
 783                 status = notify_save(notify, rec);
 784         }
 785
 786         talloc_free(rec);
 787
 788         return status;
 789 }
 790
 791
 792 /*
 793   send a notify message to another messaging server
 794 */
 795 static NTSTATUS notify_send(struct notify_context *notify, struct notify_entry *e,
 796                             const char *path, uint32_t action)
 797 {
 798         struct notify_event ev;
 799         DATA_BLOB data;
 800         NTSTATUS status;
 801         enum ndr_err_code ndr_err;
 802
 803         ev.action = action;
 804         ev.path = path;
 805         ev.private_data = e->private_data;
 806
 807         ndr_err = ndr_push_struct_blob(&data, talloc_tos(), &ev,
 808                                        (ndr_push_flags_fn_t)ndr_push_notify_event);
 809         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 810                 return ndr_map_error2ntstatus(ndr_err);
 811         }
 812
 813         status = messaging_send(notify->messaging_ctx, e->server,
 814                                 MSG_PVFS_NOTIFY, &data);
 815         TALLOC_FREE(data.data);
 816         return status;
 817 }
 818
 819 void notify_onelevel(struct notify_context *notify, uint32_t action,
 820                      uint32_t filter, struct file_id fid, const char *name)
 821 {
 822         struct notify_entry_array *array;
 823         TDB_DATA dbuf;
 824         DATA_BLOB blob;
 825         bool have_dead_entries = false;
 826         int i;
 827         NTSTATUS status;
 828
 829         if (notify == NULL) {
 830                 return;
 831         }
 832
 833         array = talloc_zero(talloc_tos(), struct notify_entry_array);
 834         if (array == NULL) {
 835                 return;
 836         }
 837
 838         status = dbwrap_fetch(notify->db_onelevel, array,
 839                               make_tdb_data((uint8_t *)&fid, sizeof(fid)),
 840                               &dbuf);
 841         if (!NT_STATUS_IS_OK(status)) {
 842                 TALLOC_FREE(array);
 843                 return;
 844         }
 845
 846         blob.data = (uint8 *)dbuf.dptr;
 847         blob.length = dbuf.dsize;
 848
 849         if (blob.length > 0) {
 850                 enum ndr_err_code ndr_err;
 851                 ndr_err = ndr_pull_struct_blob(&blob, array, array,
 852                         (ndr_pull_flags_fn_t)ndr_pull_notify_entry_array);
 853                 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 854                         DEBUG(10, ("ndr_pull_notify_entry_array failed: %s\n",
 855                                    ndr_errstr(ndr_err)));
 856                         TALLOC_FREE(array);
 857                         return;
 858                 }
 859                 if (DEBUGLEVEL >= 10) {
 860                         DEBUG(10, ("notify_onelevel:\n"));
 861                         NDR_PRINT_DEBUG(notify_entry_array, array);
 862                 }
 863         }
 864
 865         for (i=0; i<array->num_entries; i++) {
 866                 struct notify_entry *e = &array->entries[i];
 867
 868                 if ((e->filter & filter) != 0) {
 869                         status = notify_send(notify, e, name, action);
 870                         if (NT_STATUS_EQUAL(
 871                                     status, NT_STATUS_INVALID_HANDLE)) {
 872                                 /*
 873                                  * Mark the entry as dead. All entries have a
 874                                  * path set. The marker used here is setting
 875                                  * that to NULL.
 876                                  */
 877                                 e->path = NULL;
 878                                 have_dead_entries = true;
 879                         }
 880                 }
 881         }
 882
 883         if (!have_dead_entries) {
 884                 TALLOC_FREE(array);
 885                 return;
 886         }
 887
 888         for (i=0; i<array->num_entries; i++) {
 889                 struct notify_entry *e = &array->entries[i];
 890                 if (e->path != NULL) {
 891                         continue;
 892                 }
 893                 DEBUG(10, ("Deleting notify entries for process %s because "
 894                            "it's gone\n", procid_str_static(&e->server)));
 895                 /*
 896                  * Potential TODO: This might need optimizing,
 897                  * notify_remove_onelevel() does a fetch_locked() operation at
 898                  * every call. But this would only matter if a process with
 899                  * MANY notifies has died without shutting down properly.
 900                  */
 901                 notify_remove_onelevel(notify, &e->dir_id, e->private_data);
 902         }
 903
 904         TALLOC_FREE(array);
 905         return;
 906 }
 907
 908 /*
 909   trigger a notify message for anyone waiting on a matching event
 910
 911   This function is called a lot, and needs to be very fast. The unusual data structure
 912   and traversal is designed to be fast in the average case, even for large numbers of
 913   notifies
 914 */
 915 void notify_trigger(struct notify_context *notify,
 916                     uint32_t action, uint32_t filter, const char *path)
 917 {
 918         NTSTATUS status;
 919         int depth;
 920         const char *p, *next_p;
 921
 922         DEBUG(10, ("notify_trigger called action=0x%x, filter=0x%x, "
 923                    "path=%s\n", (unsigned)action, (unsigned)filter, path));
 924
 925         /* see if change notify is enabled at all */
 926         if (notify == NULL) {
 927                 return;
 928         }
 929
 930  again:
 931         status = notify_load(notify, NULL);
 932         if (!NT_STATUS_IS_OK(status)) {
 933                 return;
 934         }
 935
 936         /* loop along the given path, working with each directory depth separately */
 937         for (depth=0,p=path;
 938              p && depth < notify->array->num_depths;
 939              p=next_p,depth++) {
 940                 int p_len = p - path;
 941                 int min_i, max_i, i;
 942                 struct notify_depth *d = &notify->array->depth[depth];
 943                 uint32_t d_max_mask;
 944                 next_p = strchr(p+1, '/');
 945
 946                 /* see if there are any entries at this depth */
 947                 if (d->num_entries == 0) continue;
 948
 949                 /* try to skip based on the maximum mask. If next_p is
 950                  NULL then we know it will be a 'this directory'
 951                  match, otherwise it must be a subdir match */
 952
 953                 d_max_mask = next_p ? d->max_mask_subdir : d->max_mask;
 954
 955                 if ((filter & d_max_mask) == 0) {
 956                         continue;
 957                 }
 958
 959                 /* we know there is an entry here worth looking
 960                  for. Use a bisection search to find the first entry
 961                  with a matching path */
 962                 min_i = 0;
 963                 max_i = d->num_entries-1;
 964
 965                 while (min_i < max_i) {
 966                         struct notify_entry *e;
 967                         int cmp;
 968                         i = (min_i+max_i)/2;
 969                         e = &d->entries[i];
 970                         cmp = strncmp(path, e->path, p_len);
 971                         if (cmp == 0) {
 972                                 if (p_len == e->path_len) {
 973                                         max_i = i;
 974                                 } else {
 975                                         max_i = i-1;
 976                                 }
 977                         } else if (cmp < 0) {
 978                                 max_i = i-1;
 979                         } else {
 980                                 min_i = i+1;
 981                         }
 982                 }
 983
 984                 if (min_i != max_i) {
 985                         /* none match */
 986                         continue;
 987                 }
 988
 989                 /* we now know that the entries start at min_i */
 990                 for (i=min_i;i<d->num_entries;i++) {
 991                         struct notify_entry *e = &d->entries[i];
 992                         uint32_t e_filter;
 993                         if (p_len != e->path_len ||
 994                             strncmp(path, e->path, p_len) != 0) break;
 995
 996                         e_filter = next_p ? e->subdir_filter : e->filter;
 997
 998                         if ((filter & e_filter) == 0) {
 999                                 continue;
1000                         }
1001
1002                         status = notify_send(notify, e, path + e->path_len + 1,
1003                                              action);
1004
1005                         if (NT_STATUS_EQUAL(
1006                                     status, NT_STATUS_INVALID_HANDLE)) {
1007                                 struct server_id server = e->server;
1008
1009                                 DEBUG(10, ("Deleting notify entries for "
1010                                            "process %s because it's gone\n",
1011                                            procid_str_static(&e->server)));
1012                                 notify_remove_all(notify, &server);
1013                                 goto again;
1014                         }
1015                 }
1016         }
1017 }