misc-utils/lslocks.c

   1 /*
   2  * lslocks(8) - list local system locks
   3  *
   4  * Copyright (C) 2012 Davidlohr Bueso <dave@gnu.org>
   5  *
   6  * Very generally based on lslk(8) by Victor A. Abell <abe@purdue.edu>
   7  * Since it stopped being maintained over a decade ago, this
   8  * program should be considered its replacement.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it would be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <getopt.h>
  28 #include <stdlib.h>
  29 #include <assert.h>
  30 #include <dirent.h>
  31 #include <unistd.h>
  32 #include <sys/stat.h>
  33 #include <sys/types.h>
  34 #include <stdbool.h>
  35 #include <search.h>
  36
  37 #include <libmount.h>
  38 #include <libsmartcols.h>
  39
  40 #include "pathnames.h"
  41 #include "canonicalize.h"
  42 #include "nls.h"
  43 #include "xalloc.h"
  44 #include "strutils.h"
  45 #include "c.h"
  46 #include "cctype.h"
  47 #include "list.h"
  48 #include "closestream.h"
  49 #include "optutils.h"
  50 #include "procfs.h"
  51 #include "column-list-table.h"
  52 #include "fileutils.h"
  53
  54 /* column IDs */
  55 enum {
  56         COL_SRC = 0,
  57         COL_PID,
  58         COL_TYPE,
  59         COL_SIZE,
  60         COL_INODE,
  61         COL_MAJMIN,
  62         COL_MODE,
  63         COL_M,
  64         COL_START,
  65         COL_END,
  66         COL_PATH,
  67         COL_BLOCKER,
  68         COL_HOLDERS,
  69 };
  70
  71 /* column names */
  72 struct colinfo {
  73         const char * const      name; /* header */
  74         double                  whint; /* width hint (N < 1 is in percent of termwidth) */
  75         int                     flags; /* SCOLS_FL_* */
  76         const char              *help;
  77 };
  78
  79 /* columns descriptions */
  80 static struct colinfo infos[] = {
  81         [COL_SRC]  = { "COMMAND",15, 0, N_("command of the process holding the lock") },
  82         [COL_PID]  = { "PID",     5, SCOLS_FL_RIGHT, N_("PID of the process holding the lock") },
  83         [COL_TYPE] = { "TYPE",    5, SCOLS_FL_RIGHT, N_("kind of lock") },
  84         [COL_SIZE] = { "SIZE",    4, SCOLS_FL_RIGHT, N_("size of the lock, use <number> if --bytes is given") },
  85         [COL_INODE] = { "INODE",  5, SCOLS_FL_RIGHT, N_("inode number") },
  86         [COL_MAJMIN] = { "MAJ:MIN", 6, 0, N_("major:minor device number") },
  87         [COL_MODE] = { "MODE",    5, 0, N_("lock access mode") },
  88         [COL_M]    = { "M",       1, 0, N_("mandatory state of the lock: 0 (none), 1 (set)")},
  89         [COL_START] = { "START", 10, SCOLS_FL_RIGHT, N_("relative byte offset of the lock")},
  90         [COL_END]  = { "END",    10, SCOLS_FL_RIGHT, N_("ending offset of the lock")},
  91         [COL_PATH] = { "PATH",    0, SCOLS_FL_TRUNC, N_("path of the locked file")},
  92         [COL_BLOCKER] = { "BLOCKER", 0, SCOLS_FL_RIGHT, N_("PID of the process blocking the lock") },
  93         [COL_HOLDERS] = { "HOLDERS", 0, SCOLS_FL_WRAP, N_("holders of the lock") },
  94 };
  95
  96 static int columns[ARRAY_SIZE(infos) * 2];
  97 static size_t ncolumns;
  98
  99 static struct libmnt_table *tab;                /* /proc/self/mountinfo */
 100
 101 /* basic output flags */
 102 static int no_headings;
 103 static int no_inaccessible;
 104 static int raw;
 105 static int json;
 106 static int bytes;
 107
 108 struct lock {
 109         struct list_head locks;
 110
 111         char *cmdname;
 112         pid_t pid;
 113         char *path;
 114         char *type;
 115         char *mode;
 116         off_t start;
 117         off_t end;
 118         ino_t inode;
 119         dev_t dev;
 120         bool  mandatory,
 121               blocked;
 122         uint64_t size;
 123         int fd;
 124         int id;
 125 };
 126
 127 struct lock_tnode {
 128         dev_t dev;
 129         ino_t inode;
 130
 131         struct list_head chain;
 132 };
 133
 134 static int lock_tnode_compare(const void *a, const void *b)
 135 {
 136         struct lock_tnode *anode = ((struct lock_tnode *)a);
 137         struct lock_tnode *bnode = ((struct lock_tnode *)b);
 138
 139         if (anode->dev > bnode->dev)
 140                 return 1;
 141         else if (anode->dev < bnode->dev)
 142                 return -1;
 143
 144         if (anode->inode > bnode->inode)
 145                 return 1;
 146         else if (anode->inode < bnode->inode)
 147                 return -1;
 148
 149         return 0;
 150 }
 151
 152 static void add_to_tree(void *troot, struct lock *l)
 153 {
 154         struct lock_tnode tmp = { .dev = l->dev, .inode = l->inode, };
 155         struct lock_tnode **head = tfind(&tmp, troot, lock_tnode_compare);
 156         struct lock_tnode *new_head;
 157
 158         if (head) {
 159                 list_add_tail(&l->locks, &(*head)->chain);
 160                 return;
 161         }
 162
 163         new_head = xmalloc(sizeof(*new_head));
 164         new_head->dev = l->dev;
 165         new_head->inode = l->inode;
 166         INIT_LIST_HEAD(&new_head->chain);
 167         if (tsearch(new_head, troot, lock_tnode_compare) == NULL)
 168                 errx(EXIT_FAILURE, _("failed to allocate memory"));
 169
 170         list_add_tail(&l->locks, &new_head->chain);
 171 }
 172
 173 static void rem_lock(struct lock *lock)
 174 {
 175         if (!lock)
 176                 return;
 177
 178         free(lock->path);
 179         free(lock->mode);
 180         free(lock->cmdname);
 181         free(lock->type);
 182         list_del(&lock->locks);
 183         free(lock);
 184 }
 185
 186 static void disable_columns_truncate(void)
 187 {
 188         size_t i;
 189
 190         for (i = 0; i < ARRAY_SIZE(infos); i++)
 191                 infos[i].flags &= ~SCOLS_FL_TRUNC;
 192 }
 193
 194 /*
 195  * Associate the device's mountpoint for a filename
 196  */
 197 static char *get_fallback_filename(dev_t dev)
 198 {
 199         struct libmnt_fs *fs;
 200         char *res = NULL;
 201
 202         if (!tab) {
 203                 tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
 204                 if (!tab)
 205                         return NULL;
 206         }
 207
 208         fs = mnt_table_find_devno(tab, dev, MNT_ITER_BACKWARD);
 209         if (!fs)
 210                 return NULL;
 211
 212         xasprintf(&res, "%s...", mnt_fs_get_target(fs));
 213         return res;
 214 }
 215
 216 /*
 217  * Return the absolute path of a file from
 218  * a given inode number (and its size)
 219  */
 220 static char *get_filename_sz(ino_t inode, pid_t lock_pid, size_t *size)
 221 {
 222         struct stat sb;
 223         struct dirent *dp;
 224         DIR *dirp;
 225         int fd;
 226         char path[PATH_MAX] = { 0 },
 227              sym[PATH_MAX] = { 0 }, *ret = NULL;
 228
 229         *size = 0;
 230
 231         if (lock_pid < 0)
 232                 /* pid could be -1 for OFD locks */
 233                 return NULL;
 234
 235         /*
 236          * We know the pid so we don't have to
 237          * iterate the *entire* filesystem searching
 238          * for the damn file.
 239          */
 240         snprintf(path, sizeof(path), "/proc/%d/fd/", lock_pid);
 241         if (!(dirp = opendir(path)))
 242                 return NULL;
 243
 244         if (strlen(path) >= (sizeof(path) - 2))
 245                 goto out;
 246
 247         if ((fd = dirfd(dirp)) < 0 )
 248                 goto out;
 249
 250         while ((dp = xreaddir(dirp))) {
 251                 ssize_t len;
 252
 253                 errno = 0;
 254
 255                 /* care only for numerical descriptors */
 256                 if (!strtol(dp->d_name, (char **) NULL, 10) || errno)
 257                         continue;
 258
 259                 if (!fstatat(fd, dp->d_name, &sb, 0)
 260                     && inode != sb.st_ino)
 261                         continue;
 262
 263                 if ((len = readlinkat(fd, dp->d_name, sym, sizeof(sym) - 1)) < 1)
 264                         goto out;
 265
 266                 *size = sb.st_size;
 267                 sym[len] = '\0';
 268
 269                 ret = xstrdup(sym);
 270                 break;
 271         }
 272 out:
 273         closedir(dirp);
 274         return ret;
 275 }
 276
 277 /*
 278  * Return the inode number from a string
 279  */
 280 static ino_t get_dev_inode(char *str, dev_t *dev)
 281 {
 282         unsigned int maj = 0, min = 0;
 283         ino_t inum = 0;
 284
 285         if (sscanf(str, "%x:%x:%ju", &maj, &min, &inum) != 3)
 286                 errx(EXIT_FAILURE, _("failed to parse '%s'"), str);
 287
 288         *dev = (dev_t) makedev(maj, min);
 289         return inum;
 290 }
 291
 292 struct override_info {
 293         pid_t pid;
 294         const char *cmdname;
 295 };
 296
 297 static bool is_holder(struct lock *l, struct lock *m)
 298 {
 299         return (l->start == m->start &&
 300                 l->end == m->end &&
 301                 l->inode == m->inode &&
 302                 l->dev == m->dev &&
 303                 l->mandatory == m->mandatory &&
 304                 l->blocked == m->blocked &&
 305                 strcmp(l->type, m->type) == 0 &&
 306                 strcmp(l->mode, m->mode) == 0);
 307 }
 308
 309 static void patch_lock(struct lock *l, void *fallback)
 310 {
 311         struct lock_tnode tmp = { .dev = l->dev, .inode = l->inode, };
 312         struct lock_tnode **head = tfind(&tmp, fallback, lock_tnode_compare);
 313         struct list_head *p;
 314
 315         if (!head)
 316                 return;
 317
 318         list_for_each(p, &(*head)->chain) {
 319                 struct lock *m = list_entry(p, struct lock, locks);
 320                 if (is_holder(l, m)) {
 321                         /* size and id can be ignored. */
 322                         l->pid = m->pid;
 323                         l->cmdname = xstrdup(m->cmdname);
 324                         break;
 325                 }
 326         }
 327 }
 328
 329 static void add_to_list(void *locks, struct lock *l)
 330 {
 331         list_add(&l->locks, locks);
 332 }
 333
 334 static struct lock *get_lock(char *buf, struct override_info *oinfo, void *fallback)
 335 {
 336         int i;
 337         char *tok = NULL;
 338         size_t sz;
 339         struct lock *l = xcalloc(1, sizeof(*l));
 340         INIT_LIST_HEAD(&l->locks);
 341         l->fd = -1;
 342
 343         bool cmdname_unknown = false;
 344
 345         for (tok = strtok(buf, " "), i = 0; tok;
 346              tok = strtok(NULL, " "), i++) {
 347
 348                 /*
 349                  * /proc/locks has *exactly* 8 "blocks" of text
 350                  * separated by ' ' - check <kernel>/fs/locks.c
 351                  */
 352                 switch (i) {
 353                 case 0: /* ID: */
 354                         if (oinfo)
 355                                 l->id = -1;
 356                         else {
 357                                 tok[strlen(tok) - 1] = '\0';
 358                                 l->id = strtos32_or_err(tok, _("failed to parse ID"));
 359                         }
 360                         break;
 361                 case 1: /* posix, flock, etc */
 362                         if (strcmp(tok, "->") == 0) {   /* optional field */
 363                                 l->blocked = 1;
 364                                 i--;
 365                         } else
 366                                 l->type = xstrdup(tok);
 367                         break;
 368
 369                 case 2: /* is this a mandatory lock? other values are advisory or noinode */
 370                         l->mandatory = *tok == 'M' ? 1 : 0;
 371                         break;
 372                 case 3: /* lock mode */
 373                         l->mode = xstrdup(tok);
 374                         break;
 375
 376                 case 4: /* PID */
 377                         /*
 378                          * If user passed a pid we filter it later when adding
 379                          * to the list, no need to worry now. OFD locks use -1 PID.
 380                          */
 381                         if (oinfo) {
 382                                 l->pid = oinfo->pid;
 383                                 l->cmdname = xstrdup(oinfo->cmdname);
 384                         } else {
 385                                 /* strtopid_or_err() is not suitable here; tok can be -1.*/
 386                                 l->pid = strtos32_or_err(tok, _("invalid PID argument"));
 387                                 if (l->pid > 0) {
 388                                         l->cmdname = pid_get_cmdname(l->pid);
 389                                         if (!l->cmdname)
 390                                                 cmdname_unknown = true;
 391                                 } else
 392                                         l->cmdname = NULL;
 393                         }
 394                         break;
 395
 396                 case 5: /* device major:minor and inode number */
 397                         l->inode = get_dev_inode(tok, &l->dev);
 398                         break;
 399
 400                 case 6: /* start */
 401                         l->start = !strcmp(tok, "EOF") ? 0 :
 402                         strtou64_or_err(tok, _("failed to parse start"));
 403                         break;
 404
 405                 case 7: /* end */
 406                         /* replace '\n' character */
 407                         tok[strlen(tok)-1] = '\0';
 408                         l->end = !strcmp(tok, "EOF") ? 0 :
 409                                 strtou64_or_err(tok, _("failed to parse end"));
 410                         break;
 411                 default:
 412                         break;
 413                 }
 414         }
 415
 416         if ((!l->blocked) && fallback && !l->cmdname)
 417                 patch_lock(l, fallback);
 418         if (!l->cmdname) {
 419                 if (cmdname_unknown)
 420                         l->cmdname = xstrdup(_("(unknown)"));
 421                 else
 422                         l->cmdname = xstrdup(_("(undefined)"));
 423         }
 424         l->path = get_filename_sz(l->inode, l->pid, &sz);
 425
 426         /* no permissions -- ignore */
 427         if (!l->path && no_inaccessible) {
 428                 rem_lock(l);
 429                 return NULL;
 430         }
 431
 432         if (!l->path) {
 433                 /* probably no permission to peek into l->pid's path */
 434                 l->path = get_fallback_filename(l->dev);
 435                 l->size = 0;
 436         } else
 437                 l->size = sz;
 438
 439         return l;
 440 }
 441
 442 static int get_pid_lock(void *locks, void (*add_lock)(void *, struct lock *), FILE *fp,
 443                         pid_t pid, const char *cmdname, int fd)
 444 {
 445         char buf[PATH_MAX];
 446         struct override_info oinfo = {
 447                 .pid = pid,
 448                 .cmdname = cmdname,
 449         };
 450
 451         while (fgets(buf, sizeof(buf), fp)) {
 452                 struct lock *l;
 453                 if (strncmp(buf, "lock:\t", 6))
 454                         continue;
 455                 l = get_lock(buf + 6, &oinfo, NULL);
 456                 if (l) {
 457                         add_lock(locks, l);
 458                         l->fd = fd;
 459                 }
 460                 /* no break here.
 461                    Multiple recode locks can be taken via one fd. */
 462         }
 463
 464         return 0;
 465 }
 466
 467 static int get_pid_locks(void *locks, void (*add_lock)(void *, struct lock *), struct path_cxt *pc,
 468                          pid_t pid, const char *cmdname)
 469 {
 470         DIR *sub = NULL;
 471         struct dirent *d = NULL;
 472         int rc = 0;
 473
 474         while (ul_path_next_dirent(pc, &sub, "fdinfo", &d) == 0) {
 475                 uint64_t num;
 476                 FILE *fdinfo;
 477
 478                 if (ul_strtou64(d->d_name, &num, 10) != 0)      /* only numbers */
 479                         continue;
 480
 481                 fdinfo = ul_path_fopenf(pc, "r", "fdinfo/%ju", num);
 482                 if (fdinfo == NULL)
 483                         continue;
 484
 485                 get_pid_lock(locks, add_lock, fdinfo, pid, cmdname, (int)num);
 486                 fclose(fdinfo);
 487         }
 488
 489         return rc;
 490 }
 491
 492 static void get_pids_locks(void *locks, void (*add_lock)(void *, struct lock *))
 493 {
 494         DIR *dir;
 495         struct dirent *d;
 496         struct path_cxt *pc = NULL;
 497
 498         pc = ul_new_path(NULL);
 499         if (!pc)
 500                 err(EXIT_FAILURE, _("failed to alloc procfs handler"));
 501
 502         dir = opendir(_PATH_PROC);
 503         if (!dir)
 504                 err(EXIT_FAILURE, _("failed to open /proc"));
 505
 506         while ((d = readdir(dir))) {
 507                 pid_t pid;
 508                 char buf[BUFSIZ];
 509                 const char *cmdname = NULL;
 510
 511                 if (procfs_dirent_get_pid(d, &pid) != 0)
 512                         continue;
 513
 514                 if (procfs_process_init_path(pc, pid) != 0)
 515                         continue;
 516
 517                 if (procfs_process_get_cmdname(pc, buf, sizeof(buf)) <= 0)
 518                         continue;
 519                 cmdname = buf;
 520
 521                 get_pid_locks(locks, add_lock, pc, pid, cmdname);
 522         }
 523
 524         closedir(dir);
 525         ul_unref_path(pc);
 526
 527         return;
 528 }
 529
 530 static int get_proc_locks(void *locks, void (*add_lock)(void *, struct lock *), void *fallback)
 531 {
 532         FILE *fp;
 533         char buf[PATH_MAX];
 534
 535         if (!(fp = fopen(_PATH_PROC_LOCKS, "r")))
 536                 return -1;
 537
 538         while (fgets(buf, sizeof(buf), fp)) {
 539                 struct lock *l = get_lock(buf, NULL, fallback);
 540                 if (l)
 541                         add_lock(locks, l);
 542         }
 543
 544         fclose(fp);
 545         return 0;
 546 }
 547
 548 static int column_name_to_id(const char *name, size_t namesz)
 549 {
 550         size_t i;
 551
 552         assert(name);
 553
 554         for (i = 0; i < ARRAY_SIZE(infos); i++) {
 555                 const char *cn = infos[i].name;
 556
 557                 if (!c_strncasecmp(name, cn, namesz) && !*(cn + namesz))
 558                         return i;
 559         }
 560         warnx(_("unknown column: %s"), name);
 561         return -1;
 562 }
 563
 564 static inline int get_column_id(int num)
 565 {
 566         assert(num >= 0);
 567         assert((size_t) num < ncolumns);
 568         assert(columns[num] < (int) ARRAY_SIZE(infos));
 569
 570         return columns[num];
 571 }
 572
 573
 574 static inline const struct colinfo *get_column_info(unsigned num)
 575 {
 576         return &infos[ get_column_id(num) ];
 577 }
 578
 579 static pid_t get_blocker(int id, struct list_head *locks)
 580 {
 581         struct list_head *p;
 582
 583         list_for_each(p, locks) {
 584                 struct lock *l = list_entry(p, struct lock, locks);
 585
 586                 if (l->id == id && !l->blocked)
 587                         return l->pid;
 588         }
 589
 590         return 0;
 591 }
 592
 593 static void xstrcoholder(char **str, struct lock *l)
 594 {
 595         xstrfappend(str, "%d,%s,%d",
 596                     l->pid, l->cmdname, l->fd);
 597 }
 598
 599 static void add_scols_line(struct libscols_table *table, struct lock *l, struct list_head *locks, void *pid_locks)
 600 {
 601         size_t i;
 602         struct libscols_line *line;
 603         /*
 604          * Whenever cmdname or filename is NULL it is most
 605          * likely  because there's no read permissions
 606          * for the specified process.
 607          */
 608         const char *notfnd = "";
 609
 610         assert(l);
 611         assert(table);
 612
 613         line = scols_table_new_line(table, NULL);
 614         if (!line)
 615                 err(EXIT_FAILURE, _("failed to allocate output line"));
 616
 617         for (i = 0; i < ncolumns; i++) {
 618                 char *str = NULL;
 619
 620                 switch (get_column_id(i)) {
 621                 case COL_SRC:
 622                         xasprintf(&str, "%s", l->cmdname ? l->cmdname : notfnd);
 623                         break;
 624                 case COL_PID:
 625                         xasprintf(&str, "%d", l->pid);
 626                         break;
 627                 case COL_TYPE:
 628                         xasprintf(&str, "%s", l->type);
 629                         break;
 630                 case COL_INODE:
 631                         xasprintf(&str, "%ju", (uintmax_t) l->inode);
 632                         break;
 633                 case COL_MAJMIN:
 634                         if (json || raw)
 635                                 xasprintf(&str, "%u:%u", major(l->dev), minor(l->dev));
 636                         else
 637                                 xasprintf(&str, "%3u:%-3u", major(l->dev), minor(l->dev));
 638                         break;
 639                 case COL_SIZE:
 640                         if (!l->size)
 641                                 break;
 642                         if (bytes)
 643                                 xasprintf(&str, "%ju", l->size);
 644                         else
 645                                 str = size_to_human_string(SIZE_SUFFIX_1LETTER, l->size);
 646                         break;
 647                 case COL_MODE:
 648                         xasprintf(&str, "%s%s", l->mode, l->blocked ? "*" : "");
 649                         break;
 650                 case COL_M:
 651                         xasprintf(&str, "%d", l->mandatory ? 1 : 0);
 652                         break;
 653                 case COL_START:
 654                         xasprintf(&str, "%jd", l->start);
 655                         break;
 656                 case COL_END:
 657                         xasprintf(&str, "%jd", l->end);
 658                         break;
 659                 case COL_PATH:
 660                         xasprintf(&str, "%s", l->path ? l->path : notfnd);
 661                         break;
 662                 case COL_BLOCKER:
 663                 {
 664                         pid_t bl = l->blocked && l->id ?
 665                                                 get_blocker(l->id, locks) : 0;
 666                         if (bl)
 667                                 xasprintf(&str, "%d", (int) bl);
 668                         break;
 669                 }
 670                 case COL_HOLDERS:
 671                 {
 672                         struct lock_tnode tmp = { .dev = l->dev, .inode = l->inode, };
 673                         struct lock_tnode **head = tfind(&tmp, pid_locks, lock_tnode_compare);
 674                         struct list_head *p;
 675
 676                         if (!head)
 677                                 break;
 678
 679                         list_for_each(p, &(*head)->chain) {
 680                                 struct lock *m = list_entry(p, struct lock, locks);
 681
 682                                 if (!is_holder(l, m))
 683                                         continue;
 684
 685                                 if (str)
 686                                         xstrputc(&str, '\n');
 687                                 xstrcoholder(&str, m);
 688                         }
 689                         break;
 690                 }
 691                 default:
 692                         break;
 693                 }
 694
 695                 if (str && scols_line_refer_data(line, i, str))
 696                         err(EXIT_FAILURE, _("failed to add output data"));
 697         }
 698 }
 699
 700 static void rem_locks(struct list_head *locks)
 701 {
 702         struct list_head *p, *pnext;
 703
 704         /* destroy the list */
 705         list_for_each_safe(p, pnext, locks) {
 706                 struct lock *l = list_entry(p, struct lock, locks);
 707                 rem_lock(l);
 708         }
 709 }
 710
 711 static void rem_tnode(void *node)
 712 {
 713         struct lock_tnode *tnode = node;
 714
 715         rem_locks(&tnode->chain);
 716         free(node);
 717 }
 718
 719 static int get_json_type_for_column(int column_id, int representing_in_bytes)
 720 {
 721         switch (column_id) {
 722         case COL_SIZE:
 723                 if (!representing_in_bytes)
 724                         return SCOLS_JSON_STRING;
 725                 FALLTHROUGH;
 726         case COL_PID:
 727         case COL_START:
 728         case COL_END:
 729         case COL_BLOCKER:
 730         case COL_INODE:
 731                 return SCOLS_JSON_NUMBER;
 732         case COL_M:
 733                 return SCOLS_JSON_BOOLEAN;
 734         case COL_HOLDERS:
 735                 return SCOLS_JSON_ARRAY_STRING;
 736         default:
 737                 return SCOLS_JSON_STRING;
 738         }
 739 }
 740
 741 static int show_locks(struct list_head *locks, pid_t target_pid, void *pid_locks)
 742 {
 743         int rc = 0;
 744         size_t i;
 745         struct list_head *p;
 746         struct libscols_table *table;
 747
 748         table = scols_new_table();
 749         if (!table)
 750                 err(EXIT_FAILURE, _("failed to allocate output table"));
 751
 752         scols_table_enable_raw(table, raw);
 753         scols_table_enable_json(table, json);
 754         scols_table_enable_noheadings(table, no_headings);
 755
 756         if (json)
 757                 scols_table_set_name(table, "locks");
 758
 759         for (i = 0; i < ncolumns; i++) {
 760                 struct libscols_column *cl;
 761                 const struct colinfo *col = get_column_info(i);
 762
 763                 cl = scols_table_new_column(table, col->name, col->whint, col->flags);
 764                 if (!cl)
 765                         err(EXIT_FAILURE, _("failed to allocate output column"));
 766
 767                 if (col->flags & SCOLS_FL_WRAP) {
 768                         scols_column_set_wrapfunc(cl,
 769                                                   scols_wrapnl_chunksize,
 770                                                   scols_wrapnl_nextchunk,
 771                                                   NULL);
 772                         scols_column_set_safechars(cl, "\n");
 773                 }
 774
 775                 if (json) {
 776                         int id = get_column_id(i);
 777                         int json_type = get_json_type_for_column(id, bytes);
 778                         scols_column_set_json_type(cl, json_type);
 779                 }
 780
 781         }
 782
 783         /* prepare data for output */
 784         list_for_each(p, locks) {
 785                 struct lock *l = list_entry(p, struct lock, locks);
 786
 787                 if (target_pid && target_pid != l->pid)
 788                         continue;
 789
 790                 add_scols_line(table, l, locks, pid_locks);
 791         }
 792
 793         scols_print_table(table);
 794         scols_unref_table(table);
 795         return rc;
 796 }
 797
 798
 799 static void __attribute__((__noreturn__)) usage(void)
 800 {
 801         FILE *out = stdout;
 802
 803         fputs(USAGE_HEADER, out);
 804
 805         fprintf(out,
 806                 _(" %s [options]\n"), program_invocation_short_name);
 807
 808         fputs(USAGE_SEPARATOR, out);
 809         fputs(_("List local system locks.\n"), out);
 810
 811         fputs(USAGE_OPTIONS, out);
 812         fputs(_(" -b, --bytes            print SIZE in bytes rather than in human readable format\n"), out);
 813         fputs(_(" -J, --json             use JSON output format\n"), out);
 814         fputs(_(" -i, --noinaccessible   ignore locks without read permissions\n"), out);
 815         fputs(_(" -n, --noheadings       don't print headings\n"), out);
 816         fputs(_(" -o, --output <list>    output columns (see --list-columns)\n"), out);
 817         fputs(_("     --output-all       output all columns\n"), out);
 818         fputs(_(" -p, --pid <pid>        display only locks held by this process\n"), out);
 819         fputs(_(" -r, --raw              use the raw output format\n"), out);
 820         fputs(_(" -u, --notruncate       don't truncate text in columns\n"), out);
 821
 822         fputs(USAGE_SEPARATOR, out);
 823         fputs(_(" -H, --list-columns     list the available columns\n"), out);
 824         fprintf(out, USAGE_HELP_OPTIONS(24));
 825         fprintf(out, USAGE_MAN_TAIL("lslocks(8)"));
 826
 827         exit(EXIT_SUCCESS);
 828 }
 829
 830 static void __attribute__((__noreturn__)) list_colunms(void)
 831 {
 832         struct libscols_table *col_tb = xcolumn_list_table_new(
 833                                         "lslocks-columns", stdout, raw, json);
 834
 835         for (size_t i = 0; i < ARRAY_SIZE(infos); i++) {
 836                 if (i != COL_SIZE) {
 837                         int json_type = get_json_type_for_column(i, bytes);
 838                         xcolumn_list_table_append_line(col_tb, infos[i].name,
 839                                                        json_type, NULL,
 840                                                        _(infos[i].help));
 841                 } else
 842                         xcolumn_list_table_append_line(col_tb, infos[i].name,
 843                                                        -1, "<string|number>",
 844                                                        _(infos[i].help));
 845         }
 846
 847         scols_print_table(col_tb);
 848         scols_unref_table(col_tb);
 849
 850         exit(EXIT_SUCCESS);
 851 }
 852
 853 int main(int argc, char *argv[])
 854 {
 855         int c, rc = 0, collist = 0;
 856         struct list_head proc_locks;
 857         void *pid_locks = NULL;
 858         char *outarg = NULL;
 859         enum {
 860                 OPT_OUTPUT_ALL = CHAR_MAX + 1
 861         };
 862         static const struct option long_opts[] = {
 863                 { "bytes",      no_argument,       NULL, 'b' },
 864                 { "json",       no_argument,       NULL, 'J' },
 865                 { "pid",        required_argument, NULL, 'p' },
 866                 { "help",       no_argument,       NULL, 'h' },
 867                 { "output",     required_argument, NULL, 'o' },
 868                 { "output-all", no_argument,       NULL, OPT_OUTPUT_ALL },
 869                 { "notruncate", no_argument,       NULL, 'u' },
 870                 { "version",    no_argument,       NULL, 'V' },
 871                 { "noheadings", no_argument,       NULL, 'n' },
 872                 { "raw",        no_argument,       NULL, 'r' },
 873                 { "noinaccessible", no_argument, NULL, 'i' },
 874                 { "list-columns", no_argument,     NULL, 'H' },
 875                 { NULL, 0, NULL, 0 }
 876         };
 877
 878         static const ul_excl_t excl[] = {       /* rows and cols in ASCII order */
 879                 { 'J','r' },
 880                 { 0 }
 881         };
 882         int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
 883         pid_t target_pid = 0;
 884
 885         setlocale(LC_ALL, "");
 886         bindtextdomain(PACKAGE, LOCALEDIR);
 887         textdomain(PACKAGE);
 888         close_stdout_atexit();
 889
 890         while ((c = getopt_long(argc, argv,
 891                                 "biJp:o:nruhVH", long_opts, NULL)) != -1) {
 892
 893                 err_exclusive_options(c, long_opts, excl, excl_st);
 894
 895                 switch(c) {
 896                 case 'b':
 897                         bytes = 1;
 898                         break;
 899                 case 'i':
 900                         no_inaccessible = 1;
 901                         break;
 902                 case 'J':
 903                         json = 1;
 904                         break;
 905                 case 'p':
 906                         target_pid = strtopid_or_err(optarg, _("invalid PID argument"));
 907                         break;
 908                 case 'o':
 909                         outarg = optarg;
 910                         break;
 911                 case OPT_OUTPUT_ALL:
 912                         for (ncolumns = 0; ncolumns < ARRAY_SIZE(infos); ncolumns++)
 913                                 columns[ncolumns] = ncolumns;
 914                         break;
 915                 case 'n':
 916                         no_headings = 1;
 917                         break;
 918                 case 'r':
 919                         raw = 1;
 920                         break;
 921                 case 'u':
 922                         disable_columns_truncate();
 923                         break;
 924
 925                 case 'H':
 926                         collist = 1;
 927                         break;
 928                 case 'V':
 929                         print_version(EXIT_SUCCESS);
 930                 case 'h':
 931                         usage();
 932                 default:
 933                         errtryhelp(EXIT_FAILURE);
 934                 }
 935         }
 936
 937         if (collist)
 938                 list_colunms(); /* print end exit */
 939
 940         INIT_LIST_HEAD(&proc_locks);
 941
 942         if (!ncolumns) {
 943                 /* default columns */
 944                 columns[ncolumns++] = COL_SRC;
 945                 columns[ncolumns++] = COL_PID;
 946                 columns[ncolumns++] = COL_TYPE;
 947                 columns[ncolumns++] = COL_SIZE;
 948                 columns[ncolumns++] = COL_MODE;
 949                 columns[ncolumns++] = COL_M;
 950                 columns[ncolumns++] = COL_START;
 951                 columns[ncolumns++] = COL_END;
 952                 columns[ncolumns++] = COL_PATH;
 953         }
 954
 955         if (outarg && string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
 956                                          &ncolumns, column_name_to_id) < 0)
 957                 return EXIT_FAILURE;
 958
 959         scols_init_debug(0);
 960
 961         /* get_pids_locks() get locks related information from "lock:" fields
 962          * of /proc/$pid/fdinfo/$fd as fallback information.
 963          * get_proc_locks() used the fallback information if /proc/locks
 964          * doesn't provides enough information or provides staled information. */
 965         get_pids_locks(&pid_locks, add_to_tree);
 966         rc = get_proc_locks(&proc_locks, add_to_list, &pid_locks);
 967
 968         if (!rc && !list_empty(&proc_locks))
 969                 rc = show_locks(&proc_locks, target_pid, &pid_locks);
 970
 971         tdestroy(pid_locks, rem_tnode);
 972         rem_locks(&proc_locks);
 973
 974         mnt_unref_table(tab);
 975         return rc;
 976 }