nss/getent.c

   1 /* Copyright (c) 1998-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 /* getent: get entries from administrative database.  */
  20
  21 #include <aliases.h>
  22 #include <argp.h>
  23 #include <ctype.h>
  24 #include <error.h>
  25 #include <grp.h>
  26 #include <gshadow.h>
  27 #include <libintl.h>
  28 #include <locale.h>
  29 #include <mcheck.h>
  30 #include <netdb.h>
  31 #include <pwd.h>
  32 #include <shadow.h>
  33 #include <stdbool.h>
  34 #include <stdio.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <arpa/inet.h>
  38 #include <arpa/nameser.h>
  39 #include <netinet/ether.h>
  40 #include <netinet/in.h>
  41 #include <sys/socket.h>
  42
  43 /* Get libc version number.  */
  44 #include <version.h>
  45
  46 #define PACKAGE _libc_intl_domainname
  47
  48 /* Name and version of program.  */
  49 static void print_version (FILE *stream, struct argp_state *state);
  50 void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
  51
  52 /* Short description of parameters.  */
  53 static const char args_doc[] = N_("database [key ...]");
  54
  55 /* Supported options. */
  56 static const struct argp_option args_options[] =
  57   {
  58     { "service", 's', N_("CONFIG"), 0, N_("Service configuration to be used") },
  59     { "no-idn", 'i', NULL, 0, N_("disable IDN encoding") },
  60     { NULL, 0, NULL, 0, NULL },
  61   };
  62
  63 /* Short description of program.  */
  64 static const char doc[] = N_("Get entries from administrative database.");
  65
  66 /* Prototype for option handler.  */
  67 static error_t parse_option (int key, char *arg, struct argp_state *state);
  68
  69 /* Function to print some extra text in the help message.  */
  70 static char *more_help (int key, const char *text, void *input);
  71
  72 /* Data structure to communicate with argp functions.  */
  73 static struct argp argp =
  74   {
  75     args_options, parse_option, args_doc, doc, NULL, more_help
  76   };
  77
  78 /* Additional getaddrinfo flags for IDN encoding.  */
  79 static int idn_flags = AI_IDN | AI_CANONIDN;
  80
  81 /* Print the version information.  */
  82 static void
  83 print_version (FILE *stream, struct argp_state *state)
  84 {
  85   fprintf (stream, "getent %s%s\n", PKGVERSION, VERSION);
  86   fprintf (stream, gettext ("\
  87 Copyright (C) %s Free Software Foundation, Inc.\n\
  88 This is free software; see the source for copying conditions.  There is NO\n\
  89 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
  90 "), "2017");
  91   fprintf (stream, gettext ("Written by %s.\n"), "Thorsten Kukuk");
  92 }
  93
  94 /* This is for aliases */
  95 static void
  96 print_aliases (struct aliasent *alias)
  97 {
  98   unsigned int i = 0;
  99
 100   printf ("%s: ", alias->alias_name);
 101   for  (i = strlen (alias->alias_name); i < 14; ++i)
 102     fputs_unlocked (" ", stdout);
 103
 104   for (i = 0; i < alias->alias_members_len; ++i)
 105     printf ("%s%s",
 106             alias->alias_members [i],
 107             i + 1 == alias->alias_members_len ? "\n" : ", ");
 108 }
 109
 110 static int
 111 aliases_keys (int number, char *key[])
 112 {
 113   int result = 0;
 114   int i;
 115   struct aliasent *alias;
 116
 117   if (number == 0)
 118     {
 119       setaliasent ();
 120       while ((alias = getaliasent ()) != NULL)
 121         print_aliases (alias);
 122       endaliasent ();
 123       return result;
 124     }
 125
 126   for (i = 0; i < number; ++i)
 127     {
 128       alias = getaliasbyname (key[i]);
 129
 130       if (alias == NULL)
 131         result = 2;
 132       else
 133         print_aliases (alias);
 134     }
 135
 136   return result;
 137 }
 138
 139 /* This is for ethers */
 140 static int
 141 ethers_keys (int number, char *key[])
 142 {
 143   int result = 0;
 144   int i;
 145
 146   if (number == 0)
 147     {
 148       fprintf (stderr, _("Enumeration not supported on %s\n"), "ethers");
 149       return 3;
 150     }
 151
 152   for (i = 0; i < number; ++i)
 153     {
 154       struct ether_addr *ethp, eth;
 155       char buffer [1024], *p;
 156
 157       ethp = ether_aton (key[i]);
 158       if (ethp != NULL)
 159         {
 160           if (ether_ntohost (buffer, ethp))
 161             {
 162               result = 2;
 163               continue;
 164             }
 165           p = buffer;
 166         }
 167       else
 168         {
 169           if (ether_hostton (key[i], &eth))
 170             {
 171               result = 2;
 172               continue;
 173             }
 174           p = key[i];
 175           ethp = &eth;
 176         }
 177       printf ("%s %s\n", ether_ntoa (ethp), p);
 178     }
 179
 180   return result;
 181 }
 182
 183 /* This is for group */
 184 static void
 185 print_group (struct group *grp)
 186 {
 187   if (putgrent (grp, stdout) != 0)
 188     fprintf (stderr, "error writing group entry: %m\n");
 189 }
 190
 191 static int
 192 group_keys (int number, char *key[])
 193 {
 194   int result = 0;
 195   int i;
 196   struct group *grp;
 197
 198   if (number == 0)
 199     {
 200       setgrent ();
 201       while ((grp = getgrent ()) != NULL)
 202         print_group (grp);
 203       endgrent ();
 204       return result;
 205     }
 206
 207   for (i = 0; i < number; ++i)
 208     {
 209       errno = 0;
 210       char *ep;
 211       gid_t arg_gid = strtoul(key[i], &ep, 10);
 212
 213       if (errno != EINVAL && *key[i] != '\0' && *ep == '\0')
 214         /* Valid numeric gid.  */
 215         grp = getgrgid (arg_gid);
 216       else
 217         grp = getgrnam (key[i]);
 218
 219       if (grp == NULL)
 220         result = 2;
 221       else
 222         print_group (grp);
 223     }
 224
 225   return result;
 226 }
 227
 228 /* This is for gshadow */
 229 static void
 230 print_gshadow (struct sgrp *sg)
 231 {
 232   if (putsgent (sg, stdout) != 0)
 233     fprintf (stderr, "error writing gshadow entry: %m\n");
 234 }
 235
 236 static int
 237 gshadow_keys (int number, char *key[])
 238 {
 239   int result = 0;
 240   int i;
 241
 242   if (number == 0)
 243     {
 244       struct sgrp *sg;
 245
 246       setsgent ();
 247       while ((sg = getsgent ()) != NULL)
 248         print_gshadow (sg);
 249       endsgent ();
 250       return result;
 251     }
 252
 253   for (i = 0; i < number; ++i)
 254     {
 255       struct sgrp *sg;
 256
 257       sg = getsgnam (key[i]);
 258
 259       if (sg == NULL)
 260         result = 2;
 261       else
 262         print_gshadow (sg);
 263     }
 264
 265   return result;
 266 }
 267
 268 /* This is for hosts */
 269 static void
 270 print_hosts (struct hostent *host)
 271 {
 272   unsigned int cnt;
 273
 274   for (cnt = 0; host->h_addr_list[cnt] != NULL; ++cnt)
 275     {
 276       char buf[INET6_ADDRSTRLEN];
 277       const char *ip = inet_ntop (host->h_addrtype, host->h_addr_list[cnt],
 278                                   buf, sizeof (buf));
 279
 280       printf ("%-15s %s", ip, host->h_name);
 281
 282       unsigned int i;
 283       for (i = 0; host->h_aliases[i] != NULL; ++i)
 284         {
 285           putchar_unlocked (' ');
 286           fputs_unlocked (host->h_aliases[i], stdout);
 287         }
 288       putchar_unlocked ('\n');
 289     }
 290 }
 291
 292 static int
 293 hosts_keys (int number, char *key[])
 294 {
 295   int result = 0;
 296   int i;
 297   struct hostent *host;
 298
 299   if (number == 0)
 300     {
 301       sethostent (0);
 302       while ((host = gethostent ()) != NULL)
 303         print_hosts (host);
 304       endhostent ();
 305       return result;
 306     }
 307
 308   for (i = 0; i < number; ++i)
 309     {
 310       struct hostent *host = NULL;
 311       char addr[IN6ADDRSZ];
 312
 313       if (inet_pton (AF_INET6, key[i], &addr) > 0)
 314         host = gethostbyaddr (addr, IN6ADDRSZ, AF_INET6);
 315       else if (inet_pton (AF_INET, key[i], &addr) > 0)
 316         host = gethostbyaddr (addr, INADDRSZ, AF_INET);
 317       else if ((host = gethostbyname2 (key[i], AF_INET6)) == NULL)
 318         host = gethostbyname2 (key[i], AF_INET);
 319
 320       if (host == NULL)
 321         result = 2;
 322       else
 323         print_hosts (host);
 324     }
 325
 326   return result;
 327 }
 328
 329 /* This is for hosts, but using getaddrinfo */
 330 static int
 331 ahosts_keys_int (int af, int xflags, int number, char *key[])
 332 {
 333   int result = 0;
 334   int i;
 335   struct hostent *host;
 336
 337   if (number == 0)
 338     {
 339       sethostent (0);
 340       while ((host = gethostent ()) != NULL)
 341         print_hosts (host);
 342       endhostent ();
 343       return result;
 344     }
 345
 346   struct addrinfo hint;
 347   memset (&hint, '\0', sizeof (hint));
 348   hint.ai_flags = (AI_V4MAPPED | AI_ADDRCONFIG | AI_CANONNAME
 349                    | idn_flags | xflags);
 350   hint.ai_family = af;
 351
 352   for (i = 0; i < number; ++i)
 353     {
 354       struct addrinfo *res;
 355
 356       if (getaddrinfo (key[i], NULL, &hint, &res) != 0)
 357         result = 2;
 358       else
 359         {
 360           struct addrinfo *runp = res;
 361
 362           while (runp != NULL)
 363             {
 364               char sockbuf[20];
 365               const char *sockstr;
 366               if (runp->ai_socktype == SOCK_STREAM)
 367                 sockstr = "STREAM";
 368               else if (runp->ai_socktype == SOCK_DGRAM)
 369                 sockstr = "DGRAM";
 370               else if (runp->ai_socktype == SOCK_RAW)
 371                 sockstr = "RAW";
 372 #ifdef SOCK_SEQPACKET
 373               else if (runp->ai_socktype == SOCK_SEQPACKET)
 374                 sockstr = "SEQPACKET";
 375 #endif
 376 #ifdef SOCK_RDM
 377               else if (runp->ai_socktype == SOCK_RDM)
 378                 sockstr = "RDM";
 379 #endif
 380 #ifdef SOCK_DCCP
 381               else if (runp->ai_socktype == SOCK_DCCP)
 382                 sockstr = "DCCP";
 383 #endif
 384 #ifdef SOCK_PACKET
 385               else if (runp->ai_socktype == SOCK_PACKET)
 386                 sockstr = "PACKET";
 387 #endif
 388               else
 389                 {
 390                   snprintf (sockbuf, sizeof (sockbuf), "%d",
 391                             runp->ai_socktype);
 392                   sockstr = sockbuf;
 393                 }
 394
 395               char buf[INET6_ADDRSTRLEN];
 396               printf ("%-15s %-6s %s\n",
 397                       inet_ntop (runp->ai_family,
 398                                  runp->ai_family == AF_INET
 399                                  ? (void *) &((struct sockaddr_in *) runp->ai_addr)->sin_addr
 400                                  : (void *) &((struct sockaddr_in6 *) runp->ai_addr)->sin6_addr,
 401                                  buf, sizeof (buf)),
 402                       sockstr,
 403                       runp->ai_canonname ?: "");
 404
 405               runp = runp->ai_next;
 406             }
 407
 408           freeaddrinfo (res);
 409         }
 410     }
 411
 412   return result;
 413 }
 414
 415 static int
 416 ahosts_keys (int number, char *key[])
 417 {
 418   return ahosts_keys_int (AF_UNSPEC, 0, number, key);
 419 }
 420
 421 static int
 422 ahostsv4_keys (int number, char *key[])
 423 {
 424   return ahosts_keys_int (AF_INET, 0, number, key);
 425 }
 426
 427 static int
 428 ahostsv6_keys (int number, char *key[])
 429 {
 430   return ahosts_keys_int (AF_INET6, AI_V4MAPPED, number, key);
 431 }
 432
 433 /* This is for netgroup */
 434 static int
 435 netgroup_keys (int number, char *key[])
 436 {
 437   int result = 0;
 438
 439   if (number == 0)
 440     {
 441       fprintf (stderr, _("Enumeration not supported on %s\n"), "netgroup");
 442       return 3;
 443     }
 444
 445   if (number == 4)
 446     {
 447       char *host = strcmp (key[1], "*") == 0 ? NULL : key[1];
 448       char *user = strcmp (key[2], "*") == 0 ? NULL : key[2];
 449       char *domain = strcmp (key[3], "*") == 0 ? NULL : key[3];
 450
 451       printf ("%-21s (%s,%s,%s) = %d\n",
 452               key[0], host ?: "", user ?: "", domain ?: "",
 453               innetgr (key[0], host, user, domain));
 454     }
 455   else if (number == 1)
 456     {
 457       if (!setnetgrent (key[0]))
 458         result = 2;
 459       else
 460         {
 461           char *p[3];
 462
 463           printf ("%-21s", key[0]);
 464
 465           while (getnetgrent (p, p + 1, p + 2))
 466             printf (" (%s,%s,%s)", p[0] ?: " ", p[1] ?: "", p[2] ?: "");
 467           putchar_unlocked ('\n');
 468         }
 469     }
 470
 471   endnetgrent ();
 472
 473   return result;
 474 }
 475
 476 /* This is for initgroups */
 477 static int
 478 initgroups_keys (int number, char *key[])
 479 {
 480   int ngrps = 100;
 481   size_t grpslen = ngrps * sizeof (gid_t);
 482   gid_t *grps = alloca (grpslen);
 483
 484   if (number == 0)
 485     {
 486       fprintf (stderr, _("Enumeration not supported on %s\n"), "initgroups");
 487       return 3;
 488     }
 489
 490   for (int i = 0; i < number; ++i)
 491     {
 492       int no = ngrps;
 493       int n;
 494       while ((n = getgrouplist (key[i], -1, grps, &no)) == -1
 495              && no > ngrps)
 496         {
 497           grps = extend_alloca (grps, grpslen, no * sizeof (gid_t));
 498           ngrps = no;
 499         }
 500
 501       if (n == -1)
 502         return 1;
 503
 504       printf ("%-21s", key[i]);
 505       for (int j = 0; j < n; ++j)
 506         if (grps[j] != -1)
 507           printf (" %ld", (long int) grps[j]);
 508       putchar_unlocked ('\n');
 509     }
 510
 511   return 0;
 512 }
 513
 514 /* This is for networks */
 515 static void
 516 print_networks (struct netent *net)
 517 {
 518   unsigned int i;
 519   struct in_addr ip;
 520   ip.s_addr = htonl (net->n_net);
 521
 522   printf ("%-21s %s", net->n_name, inet_ntoa (ip));
 523
 524   i = 0;
 525   while (net->n_aliases[i] != NULL)
 526     {
 527       putchar_unlocked (' ');
 528       fputs_unlocked (net->n_aliases[i], stdout);
 529       ++i;
 530     }
 531   putchar_unlocked ('\n');
 532 }
 533
 534 static int
 535 networks_keys (int number, char *key[])
 536 {
 537   int result = 0;
 538   int i;
 539   struct netent *net;
 540
 541   if (number == 0)
 542     {
 543       setnetent (0);
 544       while ((net = getnetent ()) != NULL)
 545         print_networks (net);
 546       endnetent ();
 547       return result;
 548     }
 549
 550   for (i = 0; i < number; ++i)
 551     {
 552       if (isdigit (key[i][0]))
 553         net = getnetbyaddr (ntohl (inet_addr (key[i])), AF_UNSPEC);
 554       else
 555         net = getnetbyname (key[i]);
 556
 557       if (net == NULL)
 558         result = 2;
 559       else
 560         print_networks (net);
 561     }
 562
 563   return result;
 564 }
 565
 566 /* Now is all for passwd */
 567 static void
 568 print_passwd (struct passwd *pwd)
 569 {
 570   if (putpwent (pwd, stdout) != 0)
 571     fprintf (stderr, "error writing passwd entry: %m\n");
 572 }
 573
 574 static int
 575 passwd_keys (int number, char *key[])
 576 {
 577   int result = 0;
 578   int i;
 579   struct passwd *pwd;
 580
 581   if (number == 0)
 582     {
 583       setpwent ();
 584       while ((pwd = getpwent ()) != NULL)
 585         print_passwd (pwd);
 586       endpwent ();
 587       return result;
 588     }
 589
 590   for (i = 0; i < number; ++i)
 591     {
 592       errno = 0;
 593       char *ep;
 594       uid_t arg_uid = strtoul(key[i], &ep, 10);
 595
 596       if (errno != EINVAL && *key[i] != '\0' && *ep == '\0')
 597         /* Valid numeric uid.  */
 598         pwd = getpwuid (arg_uid);
 599       else
 600         pwd = getpwnam (key[i]);
 601
 602       if (pwd == NULL)
 603         result = 2;
 604       else
 605         print_passwd (pwd);
 606     }
 607
 608   return result;
 609 }
 610
 611 /* This is for protocols */
 612 static void
 613 print_protocols (struct protoent *proto)
 614 {
 615   unsigned int i;
 616
 617   printf ("%-21s %d", proto->p_name, proto->p_proto);
 618
 619   i = 0;
 620   while (proto->p_aliases[i] != NULL)
 621     {
 622       putchar_unlocked (' ');
 623       fputs_unlocked (proto->p_aliases[i], stdout);
 624       ++i;
 625     }
 626   putchar_unlocked ('\n');
 627 }
 628
 629 static int
 630 protocols_keys (int number, char *key[])
 631 {
 632   int result = 0;
 633   int i;
 634   struct protoent *proto;
 635
 636   if (number == 0)
 637     {
 638       setprotoent (0);
 639       while ((proto = getprotoent ()) != NULL)
 640         print_protocols (proto);
 641       endprotoent ();
 642       return result;
 643     }
 644
 645   for (i = 0; i < number; ++i)
 646     {
 647       if (isdigit (key[i][0]))
 648         proto = getprotobynumber (atol (key[i]));
 649       else
 650         proto = getprotobyname (key[i]);
 651
 652       if (proto == NULL)
 653         result = 2;
 654       else
 655         print_protocols (proto);
 656     }
 657
 658   return result;
 659 }
 660
 661 #if HAVE_SUNRPC
 662 /* Now is all for rpc */
 663 static void
 664 print_rpc (struct rpcent *rpc)
 665 {
 666   int i;
 667
 668   printf ("%-15s %d%s",
 669           rpc->r_name, rpc->r_number, rpc->r_aliases[0] ? " " : "");
 670
 671   for (i = 0; rpc->r_aliases[i]; ++i)
 672     printf (" %s", rpc->r_aliases[i]);
 673   putchar_unlocked ('\n');
 674 }
 675
 676 static int
 677 rpc_keys (int number, char *key[])
 678 {
 679   int result = 0;
 680   int i;
 681   struct rpcent *rpc;
 682
 683   if (number == 0)
 684     {
 685       setrpcent (0);
 686       while ((rpc = getrpcent ()) != NULL)
 687         print_rpc (rpc);
 688       endrpcent ();
 689       return result;
 690     }
 691
 692   for (i = 0; i < number; ++i)
 693     {
 694       if (isdigit (key[i][0]))
 695         rpc = getrpcbynumber (atol (key[i]));
 696       else
 697         rpc = getrpcbyname (key[i]);
 698
 699       if (rpc == NULL)
 700         result = 2;
 701       else
 702         print_rpc (rpc);
 703     }
 704
 705   return result;
 706 }
 707 #endif
 708
 709 /* for services */
 710 static void
 711 print_services (struct servent *serv)
 712 {
 713   unsigned int i;
 714
 715   printf ("%-21s %d/%s", serv->s_name, ntohs (serv->s_port), serv->s_proto);
 716
 717   i = 0;
 718   while (serv->s_aliases[i] != NULL)
 719     {
 720       putchar_unlocked (' ');
 721       fputs_unlocked (serv->s_aliases[i], stdout);
 722       ++i;
 723     }
 724   putchar_unlocked ('\n');
 725 }
 726
 727 static int
 728 services_keys (int number, char *key[])
 729 {
 730   int result = 0;
 731   int i;
 732   struct servent *serv;
 733
 734   if (!number)
 735     {
 736       setservent (0);
 737       while ((serv = getservent ()) != NULL)
 738         print_services (serv);
 739       endservent ();
 740       return result;
 741     }
 742
 743   for (i = 0; i < number; ++i)
 744     {
 745       struct servent *serv;
 746       char *proto = strchr (key[i], '/');
 747
 748       if (proto != NULL)
 749         *proto++ = '\0';
 750
 751       char *endptr;
 752       long port = strtol (key[i], &endptr, 10);
 753
 754       if (isdigit (key[i][0]) && *endptr == '\0'
 755           && 0 <= port && port <= 65535)
 756         serv = getservbyport (htons (port), proto);
 757       else
 758         serv = getservbyname (key[i], proto);
 759
 760       if (serv == NULL)
 761         result = 2;
 762       else
 763         print_services (serv);
 764     }
 765
 766   return result;
 767 }
 768
 769 /* This is for shadow */
 770 static void
 771 print_shadow (struct spwd *sp)
 772 {
 773   if (putspent (sp, stdout) != 0)
 774     fprintf (stderr, "error writing shadow entry: %m\n");
 775 }
 776
 777 static int
 778 shadow_keys (int number, char *key[])
 779 {
 780   int result = 0;
 781   int i;
 782
 783   if (number == 0)
 784     {
 785       struct spwd *sp;
 786
 787       setspent ();
 788       while ((sp = getspent ()) != NULL)
 789         print_shadow (sp);
 790       endspent ();
 791       return result;
 792     }
 793
 794   for (i = 0; i < number; ++i)
 795     {
 796       struct spwd *sp;
 797
 798       sp = getspnam (key[i]);
 799
 800       if (sp == NULL)
 801         result = 2;
 802       else
 803         print_shadow (sp);
 804     }
 805
 806   return result;
 807 }
 808
 809 struct
 810   {
 811     const char *name;
 812     int (*func) (int number, char *key[]);
 813   } databases[] =
 814   {
 815 #define D(name) { #name, name ## _keys },
 816 D(ahosts)
 817 D(ahostsv4)
 818 D(ahostsv6)
 819 D(aliases)
 820 D(ethers)
 821 D(group)
 822 D(gshadow)
 823 D(hosts)
 824 D(initgroups)
 825 D(netgroup)
 826 D(networks)
 827 D(passwd)
 828 D(protocols)
 829 #if HAVE_SUNRPC
 830 D(rpc)
 831 #endif
 832 D(services)
 833 D(shadow)
 834 #undef D
 835     { NULL, NULL }
 836   };
 837
 838 /* Handle arguments found by argp. */
 839 static error_t
 840 parse_option (int key, char *arg, struct argp_state *state)
 841 {
 842   char *endp;
 843   switch (key)
 844     {
 845     case 's':
 846       endp = strchr (arg, ':');
 847       if (endp == NULL)
 848         /* No specific database, change them all.  */
 849         for (int i = 0; databases[i].name != NULL; ++i)
 850           __nss_configure_lookup (databases[i].name, arg);
 851       else
 852         {
 853           int i;
 854           for (i = 0; databases[i].name != NULL; ++i)
 855             if (strncmp (databases[i].name, arg, endp - arg) == 0)
 856               {
 857                 __nss_configure_lookup (databases[i].name, endp + 1);
 858                 break;
 859               }
 860           if (databases[i].name == NULL)
 861             error (EXIT_FAILURE, 0, gettext ("Unknown database name"));
 862         }
 863       break;
 864
 865     case 'i':
 866       idn_flags = 0;
 867       break;
 868
 869     default:
 870       return ARGP_ERR_UNKNOWN;
 871     }
 872
 873   return 0;
 874 }
 875
 876
 877 static char *
 878 more_help (int key, const char *text, void *input)
 879 {
 880   switch (key)
 881     {
 882       size_t len;
 883       char *doc;
 884       FILE *fp;
 885
 886     case ARGP_KEY_HELP_EXTRA:
 887       /* We print some extra information.  */
 888       fp = open_memstream (&doc, &len);
 889       if (fp != NULL)
 890         {
 891           fputs_unlocked (_("Supported databases:\n"), fp);
 892
 893           for (int i = 0, col = 0; databases[i].name != NULL; ++i)
 894             {
 895               len = strlen (databases[i].name);
 896               if (i != 0)
 897                 {
 898                   if (col + len > 72)
 899                     {
 900                       col = 0;
 901                       fputc_unlocked ('\n', fp);
 902                     }
 903                   else
 904                     fputc_unlocked (' ', fp);
 905                 }
 906
 907               fputs_unlocked (databases[i].name, fp);
 908               col += len + 1;
 909             }
 910
 911           fputs ("\n\n", fp);
 912
 913           fprintf (fp, gettext ("\
 914 For bug reporting instructions, please see:\n\
 915 %s.\n"), REPORT_BUGS_TO);
 916
 917           if (fclose (fp) == 0)
 918             return doc;
 919         }
 920       break;
 921
 922     default:
 923       break;
 924     }
 925   return (char *) text;
 926 }
 927
 928
 929 /* the main function */
 930 int
 931 main (int argc, char *argv[])
 932 {
 933   /* Debugging support.  */
 934   mtrace ();
 935
 936   /* Set locale via LC_ALL.  */
 937   setlocale (LC_ALL, "");
 938   /* Set the text message domain.  */
 939   textdomain (PACKAGE);
 940
 941   /* Parse and process arguments.  */
 942   int remaining;
 943   argp_parse (&argp, argc, argv, 0, &remaining, NULL);
 944
 945   if ((argc - remaining) < 1)
 946     {
 947       error (0, 0, gettext ("wrong number of arguments"));
 948       argp_help (&argp, stdout, ARGP_HELP_SEE, program_invocation_short_name);
 949       return 1;
 950     }
 951
 952   for (int i = 0; databases[i].name; ++i)
 953     if (argv[remaining][0] == databases[i].name[0]
 954         && !strcmp (argv[remaining], databases[i].name))
 955       return databases[i].func (argc - remaining - 1, &argv[remaining + 1]);
 956
 957   fprintf (stderr, _("Unknown database: %s\n"), argv[remaining]);
 958   argp_help (&argp, stdout, ARGP_HELP_SEE, program_invocation_short_name);
 959   return 1;
 960 }