blockd.c

   1 #define _GNU_SOURCE
   2 #include <sys/stat.h>
   3 #include <sys/mount.h>
   4 #include <sys/wait.h>
   5
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <unistd.h>
   9 #include <fcntl.h>
  10
  11 #include <errno.h>
  12
  13 #include <linux/limits.h>
  14 #include <linux/auto_fs4.h>
  15
  16 #include <libubox/uloop.h>
  17 #include <libubox/utils.h>
  18 #include <libubox/vlist.h>
  19 #include <libubox/ulog.h>
  20 #include <libubox/avl-cmp.h>
  21 #include <libubus.h>
  22
  23 #include "libfstools/libfstools.h"
  24
  25 #define AUTOFS_MOUNT_PATH       "/tmp/run/blockd/"
  26 #define AUTOFS_TIMEOUT          30
  27 #define AUTOFS_EXPIRE_TIMER     (5 * 1000)
  28
  29 struct hotplug_context {
  30         struct uloop_process process;
  31         void *priv;
  32 };
  33
  34 struct device {
  35         struct vlist_node node;
  36         struct blob_attr *msg;
  37         char *name;
  38         char *target;
  39         int autofs;
  40         int anon;
  41 };
  42
  43 static struct uloop_fd fd_autofs_read;
  44 static int fd_autofs_write = 0;
  45 static struct ubus_auto_conn conn;
  46 struct blob_buf bb = { 0 };
  47
  48 enum {
  49         MOUNT_UUID,
  50         MOUNT_LABEL,
  51         MOUNT_ENABLE,
  52         MOUNT_TARGET,
  53         MOUNT_DEVICE,
  54         MOUNT_OPTIONS,
  55         MOUNT_AUTOFS,
  56         MOUNT_ANON,
  57         MOUNT_REMOVE,
  58         __MOUNT_MAX
  59 };
  60
  61 static const struct blobmsg_policy mount_policy[__MOUNT_MAX] = {
  62         [MOUNT_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING },
  63         [MOUNT_LABEL] = { .name = "label", .type = BLOBMSG_TYPE_STRING },
  64         [MOUNT_DEVICE] = { .name = "device", .type = BLOBMSG_TYPE_STRING },
  65         [MOUNT_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING },
  66         [MOUNT_OPTIONS] = { .name = "options", .type = BLOBMSG_TYPE_STRING },
  67         [MOUNT_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 },
  68         [MOUNT_AUTOFS] = { .name = "autofs", .type = BLOBMSG_TYPE_INT32 },
  69         [MOUNT_ANON] = { .name = "anon", .type = BLOBMSG_TYPE_INT32 },
  70         [MOUNT_REMOVE] = { .name = "remove", .type = BLOBMSG_TYPE_INT32 },
  71 };
  72
  73 enum {
  74         INFO_DEVICE,
  75         __INFO_MAX
  76 };
  77
  78 static const struct blobmsg_policy info_policy[__INFO_MAX] = {
  79         [INFO_DEVICE] = { .name = "device", .type = BLOBMSG_TYPE_STRING },
  80 };
  81
  82 static char*
  83 _find_mount_point(char *device)
  84 {
  85         char *dev, *mp;
  86
  87         if (asprintf(&dev, "/dev/%s", device) == -1)
  88                 exit(ENOMEM);
  89
  90         mp = find_mount_point(dev, 0);
  91         free(dev);
  92
  93         return mp;
  94 }
  95
  96 static int
  97 block(char *cmd, char *action, char *device, int sync, struct uloop_process *process)
  98 {
  99         pid_t pid = fork();
 100         int ret = sync;
 101         int status;
 102         char *argv[5] = { 0 };
 103         int a = 0;
 104
 105         switch (pid) {
 106         case -1:
 107                 ULOG_ERR("failed to fork block process\n");
 108                 break;
 109
 110         case 0:
 111                 uloop_end();
 112
 113                 argv[a++] = "/sbin/block";
 114                 argv[a++] = cmd;
 115                 argv[a++] = action;
 116                 argv[a++] = device;
 117                 execvp(argv[0], argv);
 118                 ULOG_ERR("failed to spawn %s %s %s\n", *argv, action, device);
 119                 exit(EXIT_FAILURE);
 120
 121         default:
 122                 if (!sync && process) {
 123                         process->pid = pid;
 124                         uloop_process_add(process);
 125                 } else if (sync) {
 126                         waitpid(pid, &status, 0);
 127                         ret = WEXITSTATUS(status);
 128                         if (ret)
 129                                 ULOG_ERR("failed to run block. %s/%s\n", action, device);
 130                 }
 131                 break;
 132         }
 133
 134         return ret;
 135 }
 136
 137 static int send_block_notification(struct ubus_context *ctx, const char *action,
 138                             const char *devname, const char *target);
 139 static int hotplug_call_mount(struct ubus_context *ctx, const char *action,
 140                               const char *devname, uloop_process_handler cb, void *priv)
 141 {
 142         char * const argv[] = { "hotplug-call", "mount", NULL };
 143         struct hotplug_context *c = NULL;
 144         pid_t pid;
 145         int err;
 146
 147         if (cb) {
 148                 c = calloc(1, sizeof(*c));
 149                 if (!c)
 150                         return -ENOMEM;
 151         }
 152
 153         pid = fork();
 154         switch (pid) {
 155         case -1:
 156                 if (c)
 157                         free(c);
 158
 159                 err = -errno;
 160                 ULOG_ERR("fork() failed\n");
 161                 return err;
 162         case 0:
 163                 uloop_end();
 164
 165                 setenv("ACTION", action, 1);
 166                 setenv("DEVICE", devname, 1);
 167
 168                 execv("/sbin/hotplug-call", argv);
 169                 exit(-1);
 170                 break;
 171         default:
 172                 if (c) {
 173                         c->process.pid = pid;
 174                         c->process.cb = cb;
 175                         c->priv = priv;
 176                         uloop_process_add(&c->process);
 177                 }
 178                 break;
 179         }
 180
 181         return 0;
 182 }
 183
 184 static void device_mount_remove_hotplug_cb(struct uloop_process *p, int stat)
 185 {
 186         struct hotplug_context *hctx = container_of(p, struct hotplug_context, process);
 187         struct device *device = hctx->priv;
 188         char *mp;
 189
 190         if (device->target)
 191                 unlink(device->target);
 192
 193         mp = _find_mount_point(device->name);
 194         if (mp) {
 195                 block("autofs", "remove", device->name, 0, NULL);
 196                 free(mp);
 197         }
 198
 199         free(device);
 200         free(hctx);
 201 }
 202
 203 static void device_mount_remove(struct ubus_context *ctx, struct device *device)
 204 {
 205         static const char *action = "remove";
 206
 207         hotplug_call_mount(ctx, action, device->name,
 208                            device_mount_remove_hotplug_cb, device);
 209
 210         send_block_notification(ctx, action, device->name, device->target);
 211 }
 212
 213 static void device_mount_add(struct ubus_context *ctx, struct device *device)
 214 {
 215         struct stat st;
 216         char *path, *tmp;
 217
 218         if (asprintf(&path, "/tmp/run/blockd/%s", device->name) == -1)
 219                 exit(ENOMEM);
 220
 221         if (!lstat(device->target, &st)) {
 222                 if (S_ISLNK(st.st_mode))
 223                         unlink(device->target);
 224                 else if (S_ISDIR(st.st_mode))
 225                         rmdir(device->target);
 226         }
 227
 228         tmp = strrchr(device->target, '/');
 229         if (tmp && tmp != device->target && tmp != &device->target[strlen(path)-1]) {
 230                 *tmp = '\0';
 231                 mkdir_p(device->target, 0755);
 232                 *tmp = '/';
 233         }
 234
 235         if (symlink(path, device->target)) {
 236                 ULOG_ERR("failed to symlink %s->%s (%d) - %m\n", device->target, path, errno);
 237         } else {
 238                 static const char *action = "add";
 239                 hotplug_call_mount(ctx, action, device->name, NULL, NULL);
 240                 send_block_notification(ctx, action, device->name, device->target);
 241         }
 242         free(path);
 243 }
 244
 245 static int
 246 device_move(struct device *device_o, struct device *device_n)
 247 {
 248         char *path;
 249
 250         if (device_o->autofs != device_n->autofs)
 251                 return -1;
 252
 253         if (device_o->anon || device_n->anon)
 254                 return -1;
 255
 256         if (device_o->autofs) {
 257                 unlink(device_o->target);
 258                 if (asprintf(&path, "/tmp/run/blockd/%s", device_n->name) == -1)
 259                         exit(ENOMEM);
 260
 261                 if (symlink(path, device_n->target))
 262                         ULOG_ERR("failed to symlink %s->%s (%d) - %m\n", device_n->target, path, errno);
 263
 264                 free(path);
 265         } else {
 266                 mkdir(device_n->target, 0755);
 267                 if (mount(device_o->target, device_n->target, NULL, MS_MOVE, NULL))
 268                         rmdir(device_n->target);
 269                 else
 270                         rmdir(device_o->target);
 271         }
 272
 273         return 0;
 274 }
 275
 276 static void vlist_nop_update(struct vlist_tree *tree,
 277                              struct vlist_node *node_new,
 278                              struct vlist_node *node_old)
 279 {
 280 }
 281
 282 VLIST_TREE(devices, avl_strcmp, vlist_nop_update, false, false);
 283
 284 static int
 285 block_hotplug(struct ubus_context *ctx, struct ubus_object *obj,
 286               struct ubus_request_data *req, const char *method,
 287               struct blob_attr *msg)
 288 {
 289         struct blob_attr *data[__MOUNT_MAX];
 290         struct device *device;
 291         struct blob_attr *_msg;
 292         char *devname, *_name;
 293         char *target = NULL, *__target;
 294         char *_target = NULL;
 295
 296         blobmsg_parse(mount_policy, __MOUNT_MAX, data, blob_data(msg), blob_len(msg));
 297
 298         if (!data[MOUNT_DEVICE])
 299                 return UBUS_STATUS_INVALID_ARGUMENT;
 300
 301         devname = blobmsg_get_string(data[MOUNT_DEVICE]);
 302
 303         if (data[MOUNT_TARGET]) {
 304                 target = blobmsg_get_string(data[MOUNT_TARGET]);
 305         } else {
 306                 if (asprintf(&_target, "/mnt/%s",
 307                              blobmsg_get_string(data[MOUNT_DEVICE])) == -1)
 308                         exit(ENOMEM);
 309
 310                 target = _target;
 311         }
 312
 313         if (data[MOUNT_REMOVE])
 314                 device = vlist_find(&devices, devname, device, node);
 315         else
 316                 device = calloc_a(sizeof(*device), &_msg, blob_raw_len(msg),
 317                                   &_name, strlen(devname) + 1, &__target, strlen(target) + 1);
 318
 319         if (!device) {
 320                 if (_target)
 321                         free(_target);
 322
 323                 return UBUS_STATUS_UNKNOWN_ERROR;
 324         }
 325
 326         if (data[MOUNT_REMOVE]) {
 327                 vlist_delete(&devices, &device->node);
 328
 329                 if (device->autofs)
 330                         device_mount_remove(ctx, device);
 331                 else
 332                         free(device);
 333
 334                 if (_target)
 335                         free(_target);
 336         } else {
 337                 struct device *old = vlist_find(&devices, devname, device, node);
 338
 339                 device->autofs = data[MOUNT_AUTOFS] ? blobmsg_get_u32(data[MOUNT_AUTOFS]) : 0;
 340                 device->anon = data[MOUNT_ANON] ? blobmsg_get_u32(data[MOUNT_ANON]) : 0;
 341                 device->msg = _msg;
 342                 memcpy(_msg, msg, blob_raw_len(msg));
 343                 device->name = _name;
 344                 strcpy(_name, devname);
 345                 device->target = __target;
 346                 strcpy(__target, target);
 347                 if (_target)
 348                         free(_target);
 349
 350                 vlist_add(&devices, &device->node, device->name);
 351
 352                 if (old && device_move(old, device)) {
 353                         device_mount_remove(ctx, old);
 354                         device_mount_add(ctx, device);
 355                         if (!device->autofs)
 356                                 block("mount", NULL, NULL, 0, NULL);
 357                 } else if (device->autofs) {
 358                         device_mount_add(ctx, device);
 359                 }
 360         }
 361
 362         return 0;
 363 }
 364
 365 static int blockd_mount(struct ubus_context *ctx, struct ubus_object *obj,
 366                         struct ubus_request_data *req, const char *method,
 367                         struct blob_attr *msg)
 368 {
 369         static const char *action = "add";
 370         struct blob_attr *data[__MOUNT_MAX];
 371         struct device *device;
 372         char *devname;
 373
 374         blobmsg_parse(mount_policy, __MOUNT_MAX, data, blob_data(msg), blob_len(msg));
 375
 376         if (!data[MOUNT_DEVICE])
 377                 return UBUS_STATUS_INVALID_ARGUMENT;
 378
 379         devname = blobmsg_get_string(data[MOUNT_DEVICE]);
 380
 381         device = vlist_find(&devices, devname, device, node);
 382         if (!device)
 383                 return UBUS_STATUS_UNKNOWN_ERROR;
 384
 385         hotplug_call_mount(ctx, action, device->name, NULL, NULL);
 386         send_block_notification(ctx, action, device->name, device->target);
 387
 388         return 0;
 389 }
 390
 391 struct blockd_umount_context {
 392         struct ubus_context *ctx;
 393         struct ubus_request_data req;
 394 };
 395
 396 static void blockd_umount_hotplug_cb(struct uloop_process *p, int stat)
 397 {
 398         struct hotplug_context *hctx = container_of(p, struct hotplug_context, process);
 399         struct blockd_umount_context *c = hctx->priv;
 400
 401         ubus_complete_deferred_request(c->ctx, &c->req, 0);
 402
 403         free(c);
 404         free(hctx);
 405 }
 406
 407 static int blockd_umount(struct ubus_context *ctx, struct ubus_object *obj,
 408                          struct ubus_request_data *req, const char *method,
 409                          struct blob_attr *msg)
 410 {
 411         struct blob_attr *data[__MOUNT_MAX];
 412         struct blockd_umount_context *c;
 413         static const char *action = "remove";
 414         char *devname;
 415         static char oldtarget[PATH_MAX];
 416         struct device *device;
 417         int err;
 418
 419         blobmsg_parse(mount_policy, __MOUNT_MAX, data, blob_data(msg), blob_len(msg));
 420
 421         if (!data[MOUNT_DEVICE])
 422                 return UBUS_STATUS_INVALID_ARGUMENT;
 423
 424         devname = blobmsg_get_string(data[MOUNT_DEVICE]);
 425         device = vlist_find(&devices, devname, device, node);
 426         if (device) {
 427                 strncpy(oldtarget, device->target, sizeof(oldtarget)-1);
 428                 oldtarget[PATH_MAX - 1] = '\0';
 429         }
 430
 431         c = calloc(1, sizeof(*c));
 432         if (!c)
 433                 return UBUS_STATUS_UNKNOWN_ERROR;
 434
 435         c->ctx = ctx;
 436         ubus_defer_request(ctx, req, &c->req);
 437
 438         err = hotplug_call_mount(ctx, action, devname, blockd_umount_hotplug_cb, c);
 439         if (err) {
 440                 free(c);
 441                 return UBUS_STATUS_UNKNOWN_ERROR;
 442         }
 443
 444         send_block_notification(ctx, action, devname, oldtarget);
 445
 446         return 0;
 447 }
 448
 449 static void block_info_dump(struct blob_buf *b, struct device *device)
 450 {
 451         struct blob_attr *v;
 452         char *mp;
 453         int rem;
 454
 455         blob_for_each_attr(v, device->msg, rem)
 456                 blobmsg_add_blob(b, v);
 457
 458         mp = _find_mount_point(device->name);
 459         if (mp) {
 460                 blobmsg_add_string(b, "mount", mp);
 461                 free(mp);
 462         } else if (device->autofs && device->target) {
 463                 blobmsg_add_string(b, "mount", device->target);
 464         }
 465 }
 466
 467 static int
 468 block_info(struct ubus_context *ctx, struct ubus_object *obj,
 469            struct ubus_request_data *req, const char *method,
 470            struct blob_attr *msg)
 471 {
 472         struct blob_attr *data[__INFO_MAX];
 473         struct device *device = NULL;
 474
 475         blobmsg_parse(info_policy, __INFO_MAX, data, blob_data(msg), blob_len(msg));
 476
 477         if (data[INFO_DEVICE]) {
 478                 device = vlist_find(&devices, blobmsg_get_string(data[INFO_DEVICE]), device, node);
 479                 if (!device)
 480                         return UBUS_STATUS_INVALID_ARGUMENT;
 481         }
 482
 483         blob_buf_init(&bb, 0);
 484         if (device) {
 485                 block_info_dump(&bb, device);
 486         } else {
 487                 void *a;
 488
 489                 a = blobmsg_open_array(&bb, "devices");
 490                 vlist_for_each_element(&devices, device, node) {
 491                         void *t;
 492
 493                         t = blobmsg_open_table(&bb, "");
 494                         block_info_dump(&bb, device);
 495                         blobmsg_close_table(&bb, t);
 496                 }
 497                 blobmsg_close_array(&bb, a);
 498         }
 499         ubus_send_reply(ctx, req, bb.head);
 500
 501         return 0;
 502 }
 503
 504 static const struct ubus_method block_methods[] = {
 505         UBUS_METHOD("hotplug", block_hotplug, mount_policy),
 506         UBUS_METHOD("mount", blockd_mount, mount_policy),
 507         UBUS_METHOD("umount", blockd_umount, mount_policy),
 508         UBUS_METHOD("info", block_info, info_policy),
 509 };
 510
 511 static struct ubus_object_type block_object_type =
 512         UBUS_OBJECT_TYPE("block", block_methods);
 513
 514 static struct ubus_object block_object = {
 515         .name = "block",
 516         .type = &block_object_type,
 517         .methods = block_methods,
 518         .n_methods = ARRAY_SIZE(block_methods),
 519 };
 520
 521 /* send ubus event for successful mounts, useful for procd triggers */
 522 static int send_block_notification(struct ubus_context *ctx, const char *action,
 523                             const char *devname, const char *target)
 524 {
 525         struct blob_buf buf = { 0 };
 526         char evname[16] = "mount.";
 527         int err;
 528
 529         if (!ctx)
 530                 return -ENXIO;
 531
 532         strncat(evname, action, sizeof(evname) - 1);
 533
 534         blob_buf_init(&buf, 0);
 535
 536         if (devname)
 537                 blobmsg_add_string(&buf, "device", devname);
 538
 539         if (target)
 540                 blobmsg_add_string(&buf, "target", target);
 541
 542         err = ubus_notify(ctx, &block_object, evname, buf.head, -1);
 543
 544         return err;
 545 }
 546
 547 static void
 548 ubus_connect_handler(struct ubus_context *ctx)
 549 {
 550         int ret;
 551
 552         ret = ubus_add_object(ctx, &block_object);
 553         if (ret)
 554                 fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
 555 }
 556
 557 static int autofs_umount(void)
 558 {
 559         umount2(AUTOFS_MOUNT_PATH, MNT_DETACH);
 560         return 0;
 561 }
 562
 563 static void autofs_read_handler(struct uloop_fd *u, unsigned int events)
 564 {
 565         union autofs_v5_packet_union pktu;
 566         const struct autofs_v5_packet *pkt;
 567         int cmd = AUTOFS_IOC_READY;
 568         struct stat st;
 569
 570         while (read(u->fd, &pktu, sizeof(pktu)) == -1) {
 571                 if (errno != EINTR)
 572                         return;
 573                 continue;
 574         }
 575
 576         if (pktu.hdr.type != autofs_ptype_missing_indirect) {
 577                 ULOG_ERR("unknown packet type %d\n", pktu.hdr.type);
 578                 return;
 579         }
 580
 581         pkt = &pktu.missing_indirect;
 582         ULOG_ERR("kernel is requesting a mount -> %s\n", pkt->name);
 583         if (lstat(pkt->name, &st) == -1)
 584                 if (block("autofs", "add", (char *)pkt->name, 1, NULL))
 585                         cmd = AUTOFS_IOC_FAIL;
 586
 587         if (ioctl(fd_autofs_write, cmd, pkt->wait_queue_token) < 0)
 588                 ULOG_ERR("failed to report back to kernel\n");
 589 }
 590
 591 static void autofs_expire(struct uloop_timeout *t)
 592 {
 593         struct autofs_packet_expire pkt;
 594
 595         while (ioctl(fd_autofs_write, AUTOFS_IOC_EXPIRE, &pkt) == 0)
 596                 block("autofs", "remove", pkt.name, 1, NULL);
 597
 598         uloop_timeout_set(t, AUTOFS_EXPIRE_TIMER);
 599 }
 600
 601 struct uloop_timeout autofs_expire_timer = {
 602         .cb = autofs_expire,
 603 };
 604
 605 static int autofs_mount(void)
 606 {
 607         unsigned long autofs_timeout = AUTOFS_TIMEOUT;
 608         int kproto_version;
 609         int pipefd[2];
 610         char source[64];
 611         char opts[64];
 612
 613         if (pipe(pipefd) < 0) {
 614                 ULOG_ERR("failed to get kernel pipe\n");
 615                 return -1;
 616         }
 617
 618         snprintf(source, sizeof(source), "mountd(pid%u)", getpid());
 619         snprintf(opts, sizeof(opts), "fd=%d,pgrp=%u,minproto=5,maxproto=5", pipefd[1], (unsigned) getpgrp());
 620         mkdir(AUTOFS_MOUNT_PATH, 0555);
 621         if (mount(source, AUTOFS_MOUNT_PATH, "autofs", 0, opts)) {
 622                 ULOG_ERR("unable to mount autofs on %s\n", AUTOFS_MOUNT_PATH);
 623                 close(pipefd[0]);
 624                 close(pipefd[1]);
 625                 return -1;
 626         }
 627         close(pipefd[1]);
 628         fd_autofs_read.fd = pipefd[0];
 629         fd_autofs_read.cb = autofs_read_handler;
 630         uloop_fd_add(&fd_autofs_read, ULOOP_READ);
 631
 632         fd_autofs_write = open(AUTOFS_MOUNT_PATH, O_RDONLY);
 633         if(fd_autofs_write < 0) {
 634                 autofs_umount();
 635                 ULOG_ERR("failed to open direcory\n");
 636                 return -1;
 637         }
 638
 639         ioctl(fd_autofs_write, AUTOFS_IOC_PROTOVER, &kproto_version);
 640         if (kproto_version != 5) {
 641                 ULOG_ERR("only kernel protocol version 5 is tested. You have %d.\n",
 642                         kproto_version);
 643                 exit(EXIT_FAILURE);
 644         }
 645         if (ioctl(fd_autofs_write, AUTOFS_IOC_SETTIMEOUT, &autofs_timeout))
 646                 ULOG_ERR("failed to set autofs timeout\n");
 647
 648         uloop_timeout_set(&autofs_expire_timer, AUTOFS_EXPIRE_TIMER);
 649
 650         fcntl(fd_autofs_write, F_SETFD, fcntl(fd_autofs_write, F_GETFD) | FD_CLOEXEC);
 651         fcntl(fd_autofs_read.fd, F_SETFD, fcntl(fd_autofs_read.fd, F_GETFD) | FD_CLOEXEC);
 652
 653         return 0;
 654 }
 655
 656 static void blockd_startup_cb(struct uloop_process *p, int stat)
 657 {
 658         send_block_notification(&conn.ctx, "ready", NULL, NULL);
 659 }
 660
 661 static struct uloop_process startup_process = {
 662         .cb = blockd_startup_cb,
 663 };
 664
 665 static void blockd_startup(struct uloop_timeout *t)
 666 {
 667         block("autofs", "start", NULL, 0, &startup_process);
 668 }
 669
 670 struct uloop_timeout startup = {
 671         .cb = blockd_startup,
 672 };
 673
 674 int main(int argc, char **argv)
 675 {
 676         /* make sure blockd is in it's own POSIX process group */
 677         setpgrp();
 678
 679         ulog_open(ULOG_SYSLOG | ULOG_STDIO, LOG_DAEMON, "blockd");
 680         uloop_init();
 681
 682         autofs_mount();
 683
 684         conn.cb = ubus_connect_handler;
 685         ubus_auto_connect(&conn);
 686
 687         uloop_timeout_set(&startup, 1000);
 688
 689         uloop_run();
 690         uloop_done();
 691
 692         autofs_umount();
 693
 694         vlist_flush_all(&devices);
 695
 696         return 0;
 697 }