sys-utils/lsns.c

   1 /*
   2  * lsns(8) - list system namespaces
   3  *
   4  * Copyright (C) 2015 Karel Zak <kzak@redhat.com>
   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 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it would 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, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <getopt.h>
  23 #include <stdlib.h>
  24 #include <assert.h>
  25 #include <dirent.h>
  26 #include <unistd.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29 #include <wchar.h>
  30 #include <libsmartcols.h>
  31
  32 #include "pathnames.h"
  33 #include "nls.h"
  34 #include "xalloc.h"
  35 #include "c.h"
  36 #include "list.h"
  37 #include "closestream.h"
  38 #include "optutils.h"
  39 #include "procutils.h"
  40 #include "strutils.h"
  41 #include "namespace.h"
  42 #include "path.h"
  43 #include "idcache.h"
  44
  45 #include "debug.h"
  46
  47 UL_DEBUG_DEFINE_MASK(lsns);
  48 UL_DEBUG_DEFINE_MASKNAMES(lsns) = UL_DEBUG_EMPTY_MASKNAMES;
  49
  50 #define LSNS_DEBUG_INIT         (1 << 1)
  51 #define LSNS_DEBUG_PROC         (1 << 2)
  52 #define LSNS_DEBUG_NS           (1 << 3)
  53 #define LSNS_DEBUG_ALL          0xFFFF
  54
  55 #define DBG(m, x)       __UL_DBG(lsns, LSNS_DEBUG_, m, x)
  56 #define ON_DBG(m, x)    __UL_DBG_CALL(lsns, LSNS_DEBUG_, m, x)
  57
  58 struct idcache *uid_cache = NULL;
  59
  60 /* column IDs */
  61 enum {
  62         COL_NS = 0,
  63         COL_TYPE,
  64         COL_PATH,
  65         COL_NPROCS,
  66         COL_PID,
  67         COL_PPID,
  68         COL_COMMAND,
  69         COL_UID,
  70         COL_USER
  71 };
  72
  73 /* column names */
  74 struct colinfo {
  75         const char *name; /* header */
  76         double     whint; /* width hint (N < 1 is in percent of termwidth) */
  77         int        flags; /* SCOLS_FL_* */
  78         const char *help;
  79 };
  80
  81 /* columns descriptions */
  82 static const struct colinfo infos[] = {
  83         [COL_NS]      = { "NS",     10, SCOLS_FL_RIGHT, N_("command of the process holding the lock") },
  84         [COL_TYPE]    = { "TYPE",    5, 0, N_("kind of namespace") },
  85         [COL_PATH]    = { "PATH",    0, 0, N_("path to the namespace")},
  86         [COL_NPROCS]  = { "NPROCS",  5, SCOLS_FL_RIGHT, N_("number of processes in the namespace") },
  87         [COL_PID]     = { "PID",     5, SCOLS_FL_RIGHT, N_("lowers PID in the namespace") },
  88         [COL_PPID]    = { "PPID",    5, SCOLS_FL_RIGHT, N_("PPID of the PID") },
  89         [COL_COMMAND] = { "COMMAND", 0, SCOLS_FL_TRUNC, N_("command line of the PID")},
  90         [COL_UID]     = { "UID",     0, SCOLS_FL_RIGHT, N_("user ID of the PID")},
  91         [COL_USER]    = { "USER",    0, 0, N_("username of the PID")}
  92 };
  93
  94 static int columns[ARRAY_SIZE(infos) * 2];
  95 static size_t ncolumns;
  96
  97 enum {
  98         LSNS_ID_MNT = 0,
  99         LSNS_ID_NET,
 100         LSNS_ID_PID,
 101         LSNS_ID_UTS,
 102         LSNS_ID_IPC,
 103         LSNS_ID_USER
 104 };
 105
 106 static char *ns_names[] = {
 107         [LSNS_ID_MNT] = "mnt",
 108         [LSNS_ID_NET] = "net",
 109         [LSNS_ID_PID] = "pid",
 110         [LSNS_ID_UTS] = "uts",
 111         [LSNS_ID_IPC] = "ipc",
 112         [LSNS_ID_USER] = "user"
 113 };
 114
 115 struct lsns_namespace {
 116         ino_t id;
 117         int type;                       /* LSNS_* */
 118         int nprocs;
 119
 120         struct lsns_process *proc;
 121
 122         struct list_head namespaces;    /* lsns->processes member */
 123         struct list_head processes;     /* head of lsns_process *siblings */
 124 };
 125
 126 struct lsns_process {
 127         pid_t pid;              /* process PID */
 128         pid_t ppid;             /* parent's PID */
 129         pid_t tpid;             /* thread group */
 130         char state;
 131         uid_t uid;
 132
 133         ino_t            ns_ids[ARRAY_SIZE(ns_names)];
 134         struct list_head ns_siblings[ARRAY_SIZE(ns_names)];
 135
 136         struct list_head processes;     /* list of processes */
 137
 138         struct libscols_line *outline;
 139         struct lsns_process *parent;
 140 };
 141
 142 struct lsns {
 143         struct list_head processes;
 144         struct list_head namespaces;
 145
 146         pid_t   fltr_pid;       /* filter out by PID */
 147         ino_t   fltr_ns;        /* filter out by namespace */
 148         int     fltr_types[ARRAY_SIZE(ns_names)];
 149         int     fltr_ntypes;
 150
 151         unsigned int raw        : 1,
 152                      json       : 1,
 153                      tree       : 1,
 154                      list       : 1,
 155                      notrunc    : 1,
 156                      no_headings: 1;
 157 };
 158
 159 static void lsns_init_debug(void)
 160 {
 161         __UL_INIT_DEBUG(lsns, LSNS_DEBUG_, 0, LSNS_DEBUG);
 162 }
 163
 164 static int ns_name2type(const char *name)
 165 {
 166         size_t i;
 167
 168         for (i = 0; i < ARRAY_SIZE(ns_names); i++) {
 169                 if (strcmp(ns_names[i], name) == 0)
 170                         return i;
 171         }
 172         return -1;
 173 }
 174
 175 static int column_name_to_id(const char *name, size_t namesz)
 176 {
 177         size_t i;
 178
 179         assert(name);
 180
 181         for (i = 0; i < ARRAY_SIZE(infos); i++) {
 182                 const char *cn = infos[i].name;
 183
 184                 if (!strncasecmp(name, cn, namesz) && !*(cn + namesz))
 185                         return i;
 186         }
 187         warnx(_("unknown column: %s"), name);
 188         return -1;
 189 }
 190
 191 static inline int get_column_id(int num)
 192 {
 193         assert(num >= 0);
 194         assert((size_t) num < ncolumns);
 195         assert(columns[num] < (int) ARRAY_SIZE(infos));
 196
 197         return columns[num];
 198 }
 199
 200 static inline const struct colinfo *get_column_info(unsigned num)
 201 {
 202         return &infos[ get_column_id(num) ];
 203 }
 204
 205 static ino_t get_ns_ino(int dir, const char *nsname, ino_t *ino)
 206 {
 207         struct stat st;
 208         char path[16];
 209
 210         snprintf(path, sizeof(path), "ns/%s", nsname);
 211
 212         if (fstatat(dir, path, &st, 0) != 0)
 213                 return -errno;
 214         *ino = st.st_ino;
 215         return 0;
 216 }
 217
 218
 219 static int read_process(struct lsns *ls, pid_t pid)
 220 {
 221         struct lsns_process *p = NULL;
 222         char buf[BUFSIZ];
 223         DIR *dir;
 224         int rc = 0, fd;
 225         FILE *f = NULL;
 226         size_t i;
 227         struct stat st;
 228
 229         DBG(PROC, ul_debug("reading %d", (int) pid));
 230
 231         snprintf(buf, sizeof(buf), "/proc/%d", pid);
 232         dir = opendir(buf);
 233         if (!dir)
 234                 return -errno;
 235
 236         p = calloc(1, sizeof(*p));
 237         if (!p) {
 238                 rc = -ENOMEM;
 239                 goto done;
 240         }
 241
 242         if (fstat(dirfd(dir), &st) == 0) {
 243                 p->uid = st.st_uid;
 244                 add_uid(uid_cache, st.st_uid);
 245         }
 246
 247         fd = openat(dirfd(dir), "stat", O_RDONLY);
 248         if (fd < 0) {
 249                 rc = -errno;
 250                 goto done;
 251         }
 252         if (!(f = fdopen(fd, "r"))) {
 253                 rc = -errno;
 254                 goto done;
 255         }
 256         rc = fscanf(f, "%d %*s %c %d*[^\n]", &p->pid, &p->state, &p->ppid);
 257         if (rc != 3) {
 258                 rc = -errno;
 259                 goto done;
 260         }
 261         rc = 0;
 262
 263         for (i = 0; i < ARRAY_SIZE(p->ns_ids); i++) {
 264                 INIT_LIST_HEAD(&p->ns_siblings[i]);
 265
 266                 if (!ls->fltr_types[i])
 267                         continue;
 268
 269                 rc = get_ns_ino(dirfd(dir), ns_names[i], &p->ns_ids[i]);
 270                 if (rc && rc != -EACCES)
 271                         goto done;
 272                 rc = 0;
 273         }
 274
 275         INIT_LIST_HEAD(&p->processes);
 276
 277         DBG(PROC, ul_debugobj(p, "new pid=%d", p->pid));
 278         list_add_tail(&p->processes, &ls->processes);
 279 done:
 280         if (f)
 281                 fclose(f);
 282         closedir(dir);
 283         if (rc)
 284                 free(p);
 285         return rc;
 286 }
 287
 288 static int read_processes(struct lsns *ls)
 289 {
 290         struct proc_processes *proc = NULL;
 291         pid_t pid;
 292         int rc = 0;
 293
 294         DBG(PROC, ul_debug("opening /proc"));
 295
 296         if (!(proc = proc_open_processes())) {
 297                 rc = -errno;
 298                 goto done;
 299         }
 300
 301         while (proc_next_pid(proc, &pid) == 0) {
 302                 rc = read_process(ls, pid);
 303                 if (rc && rc != -EACCES)
 304                         break;
 305                 rc = 0;
 306         }
 307 done:
 308         DBG(PROC, ul_debug("closing /proc"));
 309         proc_close_processes(proc);
 310         return rc;
 311 }
 312
 313 static struct lsns_namespace *get_namespace(struct lsns *ls, ino_t ino)
 314 {
 315         struct list_head *p;
 316
 317         list_for_each(p, &ls->namespaces) {
 318                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 319
 320                 if (ns->id == ino)
 321                         return ns;
 322         }
 323         return NULL;
 324 }
 325
 326 static int namespace_has_process(struct lsns_namespace *ns, pid_t pid)
 327 {
 328         struct list_head *p;
 329
 330         list_for_each(p, &ns->processes) {
 331                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 332
 333                 if (proc->pid == pid)
 334                         return 1;
 335         }
 336         return 0;
 337 }
 338
 339 static struct lsns_namespace *add_namespace(struct lsns *ls, int type, ino_t ino)
 340 {
 341         struct lsns_namespace *ns = calloc(1, sizeof(*ns));
 342
 343         if (!ns)
 344                 return NULL;
 345
 346         DBG(NS, ul_debugobj(ns, "new %s[%lu]", ns_names[type], ino));
 347
 348         INIT_LIST_HEAD(&ns->processes);
 349         INIT_LIST_HEAD(&ns->namespaces);
 350
 351         ns->type = type;
 352         ns->id = ino;
 353
 354         list_add_tail(&ns->namespaces, &ls->namespaces);
 355         return ns;
 356 }
 357
 358 static int add_process_to_namespace(struct lsns *ls, struct lsns_namespace *ns, struct lsns_process *proc)
 359 {
 360         struct list_head *p;
 361
 362         DBG(NS, ul_debugobj(ns, "add process [%p] pid=%d to %s[%lu]", proc, proc->pid, ns_names[ns->type], ns->id));
 363
 364         list_for_each(p, &ls->processes) {
 365                 struct lsns_process *xproc = list_entry(p, struct lsns_process, processes);
 366
 367                 if (xproc->pid == proc->ppid)           /* my parent */
 368                         proc->parent = xproc;
 369                 else if (xproc->ppid == proc->pid)      /* my child */
 370                         xproc->parent = proc;
 371         }
 372
 373         list_add_tail(&proc->ns_siblings[ns->type], &ns->processes);
 374         ns->nprocs++;
 375
 376         if (!ns->proc || ns->proc->pid > proc->pid)
 377                 ns->proc = proc;
 378
 379         return 0;
 380 }
 381
 382 static int read_namespaces(struct lsns *ls)
 383 {
 384         struct list_head *p;
 385
 386         DBG(NS, ul_debug("reading namespace"));
 387
 388         list_for_each(p, &ls->processes) {
 389                 size_t i;
 390                 struct lsns_namespace *ns;
 391                 struct lsns_process *proc = list_entry(p, struct lsns_process, processes);
 392
 393                 for (i = 0; i < ARRAY_SIZE(proc->ns_ids); i++) {
 394                         if (proc->ns_ids[i] == 0)
 395                                 continue;
 396                         if (!(ns = get_namespace(ls, proc->ns_ids[i]))) {
 397                                 ns = add_namespace(ls, i, proc->ns_ids[i]);
 398                                 if (!ns)
 399                                         return -ENOMEM;
 400                         }
 401                         add_process_to_namespace(ls, ns, proc);
 402                 }
 403         }
 404
 405         return 0;
 406 }
 407
 408 static void add_scols_line(struct lsns *ls, struct libscols_table *table,
 409                            struct lsns_namespace *ns, struct lsns_process *proc)
 410 {
 411         size_t i;
 412         struct libscols_line *line;
 413
 414         assert(ns);
 415         assert(table);
 416
 417         line = scols_table_new_line(table,
 418                         ls->tree && proc->parent ? proc->parent->outline : NULL);
 419         if (!line) {
 420                 warn(_("failed to add line to output"));
 421                 return;
 422         }
 423
 424         for (i = 0; i < ncolumns; i++) {
 425                 char *str = NULL;
 426
 427                 switch (get_column_id(i)) {
 428                 case COL_NS:
 429                         xasprintf(&str, "%lu", ns->id);
 430                         break;
 431                 case COL_PID:
 432                         xasprintf(&str, "%d", (int) proc->pid);
 433                         break;
 434                 case COL_PPID:
 435                         xasprintf(&str, "%d", (int) proc->ppid);
 436                         break;
 437                 case COL_TYPE:
 438                         xasprintf(&str, "%s", ns_names[ns->type]);
 439                         break;
 440                 case COL_NPROCS:
 441                         xasprintf(&str, "%d", ns->nprocs);
 442                         break;
 443                 case COL_COMMAND:
 444                         str = proc_get_command(proc->pid);
 445                         if (!str)
 446                                 str = proc_get_command_name(proc->pid);
 447                         break;
 448                 case COL_PATH:
 449                         xasprintf(&str, "/proc/%d/ns/%s", (int) proc->pid, ns_names[ns->type]);
 450                         break;
 451                 case COL_UID:
 452                         xasprintf(&str, "%d", (int) proc->uid);
 453                         break;
 454                 case COL_USER:
 455                         xasprintf(&str, "%s", get_id(uid_cache, proc->uid)->name);
 456                         break;
 457                 default:
 458                         break;
 459                 }
 460
 461                 if (str)
 462                         scols_line_set_data(line, i, str);
 463         }
 464
 465         proc->outline = line;
 466 }
 467
 468 static struct libscols_table *init_scols_table(struct lsns *ls)
 469 {
 470         struct libscols_table *tab;
 471         size_t i;
 472
 473         tab = scols_new_table();
 474         if (!tab) {
 475                 warn(_("failed to initialize output table"));
 476                 return NULL;
 477         }
 478
 479         scols_table_enable_raw(tab, ls->raw);
 480         scols_table_enable_json(tab, ls->json);
 481         scols_table_enable_noheadings(tab, ls->no_headings);
 482
 483         if (ls->json)
 484                 scols_table_set_name(tab, "namespaces");
 485
 486         for (i = 0; i < ncolumns; i++) {
 487                 const struct colinfo *col = get_column_info(i);
 488                 int flags = col->flags;
 489
 490                 if (ls->notrunc)
 491                        flags &= ~SCOLS_FL_TRUNC;
 492                 if (ls->tree && get_column_id(i) == COL_COMMAND)
 493                         flags |= SCOLS_FL_TREE;
 494
 495                 if (!scols_table_new_column(tab, col->name, col->whint, flags)) {
 496                         warnx(_("failed to initialize output column"));
 497                         goto err;
 498                 }
 499         }
 500
 501         return tab;
 502 err:
 503         scols_unref_table(tab);
 504         return NULL;
 505 }
 506
 507 static int show_namespaces(struct lsns *ls)
 508 {
 509         struct libscols_table *tab;
 510         struct list_head *p;
 511         int rc = 0;
 512
 513         tab = init_scols_table(ls);
 514         if (!tab)
 515                 return -ENOMEM;
 516
 517         list_for_each(p, &ls->namespaces) {
 518                 struct lsns_namespace *ns = list_entry(p, struct lsns_namespace, namespaces);
 519
 520                 if (ls->fltr_pid != 0 && !namespace_has_process(ns, ls->fltr_pid))
 521                         continue;
 522
 523                 add_scols_line(ls, tab, ns, ns->proc);
 524         }
 525
 526         scols_print_table(tab);
 527         scols_unref_table(tab);
 528         return rc;
 529 }
 530
 531 static void show_process(struct lsns *ls, struct libscols_table *tab,
 532                          struct lsns_process *proc, struct lsns_namespace *ns)
 533 {
 534         /*
 535          * create a tree from parent->child relation, but only if the parent is
 536          * within the same namespace
 537          */
 538         if (ls->tree
 539             && proc->parent
 540             && !proc->parent->outline
 541             && proc->parent->ns_ids[ns->type] == proc->ns_ids[ns->type])
 542                 show_process(ls, tab, proc->parent, ns);
 543
 544         add_scols_line(ls, tab, ns, proc);
 545 }
 546
 547
 548 static int show_namespace_processes(struct lsns *ls, struct lsns_namespace *ns)
 549 {
 550         struct libscols_table *tab;
 551         struct list_head *p;
 552
 553         tab = init_scols_table(ls);
 554         if (!tab)
 555                 return -ENOMEM;
 556
 557         list_for_each(p, &ns->processes) {
 558                 struct lsns_process *proc = list_entry(p, struct lsns_process, ns_siblings[ns->type]);
 559                 show_process(ls, tab, proc, ns);
 560         }
 561
 562
 563         scols_print_table(tab);
 564         scols_unref_table(tab);
 565         return 0;
 566 }
 567
 568 static void __attribute__ ((__noreturn__)) usage(FILE * out)
 569 {
 570         size_t i;
 571
 572         fputs(USAGE_HEADER, out);
 573
 574         fprintf(out,
 575                 _(" %s [options] [<namespace>]\n"), program_invocation_short_name);
 576
 577         fputs(USAGE_SEPARATOR, out);
 578         fputs(_("List system namespaces.\n"), out);
 579
 580         fputs(USAGE_OPTIONS, out);
 581         fputs(_(" -J, --json             use JSON output format\n"), out);
 582         fputs(_(" -l, --list             use list format output\n"), out);
 583         fputs(_(" -n, --noheadings       don't print headings\n"), out);
 584         fputs(_(" -o, --output <list>    define which output columns to use\n"), out);
 585         fputs(_(" -p, --task <pid>       print process namespaces\n"), out);
 586         fputs(_(" -r, --raw              use the raw output format\n"), out);
 587         fputs(_(" -u, --notruncate       don't truncate text in columns\n"), out);
 588         fputs(_(" -t, --type <name>      namespace type (mnt, net, ipc, user, pid, uts)\n"), out);
 589
 590         fputs(USAGE_SEPARATOR, out);
 591         fputs(USAGE_HELP, out);
 592         fputs(USAGE_VERSION, out);
 593
 594         fputs(_("\nAvailable columns (for --output):\n"), out);
 595
 596         for (i = 0; i < ARRAY_SIZE(infos); i++)
 597                 fprintf(out, " %11s  %s\n", infos[i].name, _(infos[i].help));
 598
 599         fprintf(out, USAGE_MAN_TAIL("lsns(8)"));
 600
 601         exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
 602 }
 603
 604
 605 int main(int argc, char *argv[])
 606 {
 607         struct lsns ls;
 608         int c;
 609         int r = 0;
 610         char *outarg = NULL;
 611         static const struct option long_opts[] = {
 612                 { "json",       no_argument,       NULL, 'J' },
 613                 { "task",       required_argument, NULL, 'p' },
 614                 { "help",       no_argument,       NULL, 'h' },
 615                 { "output",     required_argument, NULL, 'o' },
 616                 { "notruncate", no_argument,       NULL, 'u' },
 617                 { "version",    no_argument,       NULL, 'V' },
 618                 { "noheadings", no_argument,       NULL, 'n' },
 619                 { "list",       no_argument,       NULL, 'l' },
 620                 { "raw",        no_argument,       NULL, 'r' },
 621                 { "type",       required_argument, NULL, 't' },
 622                 { NULL, 0, NULL, 0 }
 623         };
 624
 625         static const ul_excl_t excl[] = {       /* rows and cols in ASCII order */
 626                 { 'J','r' },
 627                 { 0 }
 628         };
 629         int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
 630
 631         setlocale(LC_ALL, "");
 632         bindtextdomain(PACKAGE, LOCALEDIR);
 633         textdomain(PACKAGE);
 634         atexit(close_stdout);
 635
 636         lsns_init_debug();
 637         memset(&ls, 0, sizeof(ls));
 638
 639         INIT_LIST_HEAD(&ls.processes);
 640         INIT_LIST_HEAD(&ls.namespaces);
 641
 642         while ((c = getopt_long(argc, argv,
 643                                 "Jlp:o:nruhVt:", long_opts, NULL)) != -1) {
 644
 645                 err_exclusive_options(c, long_opts, excl, excl_st);
 646
 647                 switch(c) {
 648                 case 'J':
 649                         ls.json = 1;
 650                         break;
 651                 case 'l':
 652                         ls.list = 1;
 653                         break;
 654                 case 'o':
 655                         outarg = optarg;
 656                         break;
 657                 case 'V':
 658                         printf(UTIL_LINUX_VERSION);
 659                         return EXIT_SUCCESS;
 660                 case 'p':
 661                         ls.fltr_pid = strtos32_or_err(optarg, _("invalid PID argument"));
 662                         break;
 663                 case 'h':
 664                         usage(stdout);
 665                 case 'n':
 666                         ls.no_headings = 1;
 667                         break;
 668                 case 'r':
 669                         ls.raw = 1;
 670                         break;
 671                 case 'u':
 672                         ls.notrunc = 1;
 673                         break;
 674                 case 't':
 675                 {
 676                         int type = ns_name2type(optarg);
 677                         if (type < 0)
 678                                 errx(EXIT_FAILURE, _("unknown namespace type: %s"), optarg);
 679                         ls.fltr_types[type] = 1;
 680                         ls.fltr_ntypes++;
 681                         break;
 682                 }
 683                 case '?':
 684                 default:
 685                         usage(stderr);
 686                 }
 687         }
 688
 689         if (!ls.fltr_ntypes) {
 690                 size_t i;
 691                 for (i = 0; i < ARRAY_SIZE(ns_names); i++)
 692                         ls.fltr_types[i] = 1;
 693         }
 694
 695         if (optind < argc) {
 696                 if (ls.fltr_pid)
 697                         errx(EXIT_FAILURE, _("--task is mutually exclusive with <namespace>"));
 698                 ls.fltr_ns = strtou64_or_err(argv[optind], _("invalid namespace argument"));
 699                 ls.tree = ls.list ? 0 : 1;
 700
 701                 if (!ncolumns) {
 702                         columns[ncolumns++] = COL_PID;
 703                         columns[ncolumns++] = COL_PPID;
 704                         columns[ncolumns++] = COL_USER;
 705                         columns[ncolumns++] = COL_COMMAND;
 706                 }
 707         }
 708
 709         if (!ncolumns) {
 710                 columns[ncolumns++] = COL_NS;
 711                 columns[ncolumns++] = COL_TYPE;
 712                 columns[ncolumns++] = COL_NPROCS;
 713                 columns[ncolumns++] = COL_PID;
 714                 columns[ncolumns++] = COL_USER;
 715                 columns[ncolumns++] = COL_COMMAND;
 716         }
 717
 718         if (outarg && string_add_to_idarray(outarg, columns, ARRAY_SIZE(columns),
 719                                          &ncolumns, column_name_to_id) < 0)
 720                 return EXIT_FAILURE;
 721
 722         scols_init_debug(0);
 723
 724         uid_cache = new_idcache();
 725         if (!uid_cache)
 726                 err(EXIT_FAILURE, _("failed to allocate UID cache"));
 727
 728         r = read_processes(&ls);
 729         if (!r)
 730                 r = read_namespaces(&ls);
 731         if (!r) {
 732                 if (ls.fltr_ns) {
 733                         struct lsns_namespace *ns = get_namespace(&ls, ls.fltr_ns);
 734
 735                         if (!ns)
 736                                 errx(EXIT_FAILURE, _("not found namespace: %ju"), (uintmax_t) ls.fltr_ns);
 737                         r = show_namespace_processes(&ls, ns);
 738                 } else
 739                         r = show_namespaces(&ls);
 740         }
 741
 742         free_idcache(uid_cache);
 743         return r == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
 744 }