gethostnamadr.c revision 158115
1/*- 2 * Copyright (c) 1994, Garrett Wollman 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26#include <sys/cdefs.h> 27__FBSDID("$FreeBSD: head/lib/libc/net/gethostnamadr.c 158115 2006-04-28 12:03:38Z ume $"); 28 29#include "namespace.h" 30#include "reentrant.h" 31#include <sys/param.h> 32#include <sys/socket.h> 33#include <netinet/in.h> 34#include <arpa/inet.h> 35#include <netdb.h> 36#include <stdio.h> 37#include <ctype.h> 38#include <errno.h> 39#include <stdlib.h> 40#include <string.h> 41#include <stdarg.h> 42#include <nsswitch.h> 43#include <arpa/nameser.h> /* XXX hack for _res */ 44#include <resolv.h> /* XXX hack for _res */ 45#include "un-namespace.h" 46#include "netdb_private.h" 47#ifdef NS_CACHING 48#include "nscache.h" 49#endif 50 51extern int _ht_gethostbyname(void *, void *, va_list); 52extern int _dns_gethostbyname(void *, void *, va_list); 53extern int _nis_gethostbyname(void *, void *, va_list); 54extern int _ht_gethostbyaddr(void *, void *, va_list); 55extern int _dns_gethostbyaddr(void *, void *, va_list); 56extern int _nis_gethostbyaddr(void *, void *, va_list); 57 58static int gethostbyname_internal(const char *, int, struct hostent *, char *, 59 size_t, struct hostent **, int *, res_state); 60 61/* Host lookup order if nsswitch.conf is broken or nonexistant */ 62static const ns_src default_src[] = { 63 { NSSRC_FILES, NS_SUCCESS }, 64 { NSSRC_DNS, NS_SUCCESS }, 65 { 0 } 66}; 67#ifdef NS_CACHING 68static int host_id_func(char *, size_t *, va_list, void *); 69static int host_marshal_func(char *, size_t *, void *, va_list, void *); 70static int host_unmarshal_func(char *, size_t, void *, va_list, void *); 71#endif 72 73NETDB_THREAD_ALLOC(hostent) 74NETDB_THREAD_ALLOC(hostent_data) 75NETDB_THREAD_ALLOC(hostdata) 76 77static void 78hostent_free(void *ptr) 79{ 80 free(ptr); 81} 82 83static void 84hostent_data_free(void *ptr) 85{ 86 struct hostent_data *hed = ptr; 87 88 if (hed == NULL) 89 return; 90 hed->stayopen = 0; 91 _endhosthtent(hed); 92 free(hed); 93} 94 95static void 96hostdata_free(void *ptr) 97{ 98 free(ptr); 99} 100 101int 102__copy_hostent(struct hostent *he, struct hostent *hptr, char *buf, 103 size_t buflen) 104{ 105 char *cp; 106 char **ptr; 107 int i, n; 108 int nptr, len; 109 110 /* Find out the amount of space required to store the answer. */ 111 nptr = 2; /* NULL ptrs */ 112 len = (char *)ALIGN(buf) - buf; 113 for (i = 0; he->h_addr_list[i]; i++, nptr++) { 114 len += he->h_length; 115 } 116 for (i = 0; he->h_aliases[i]; i++, nptr++) { 117 len += strlen(he->h_aliases[i]) + 1; 118 } 119 len += strlen(he->h_name) + 1; 120 len += nptr * sizeof(char*); 121 122 if (len > buflen) { 123 errno = ERANGE; 124 return (-1); 125 } 126 127 /* copy address size and type */ 128 hptr->h_addrtype = he->h_addrtype; 129 n = hptr->h_length = he->h_length; 130 131 ptr = (char **)ALIGN(buf); 132 cp = (char *)ALIGN(buf) + nptr * sizeof(char *); 133 134 /* copy address list */ 135 hptr->h_addr_list = ptr; 136 for (i = 0; he->h_addr_list[i]; i++ , ptr++) { 137 memcpy(cp, he->h_addr_list[i], n); 138 hptr->h_addr_list[i] = cp; 139 cp += n; 140 } 141 hptr->h_addr_list[i] = NULL; 142 ptr++; 143 144 /* copy official name */ 145 n = strlen(he->h_name) + 1; 146 strcpy(cp, he->h_name); 147 hptr->h_name = cp; 148 cp += n; 149 150 /* copy aliases */ 151 hptr->h_aliases = ptr; 152 for (i = 0 ; he->h_aliases[i]; i++) { 153 n = strlen(he->h_aliases[i]) + 1; 154 strcpy(cp, he->h_aliases[i]); 155 hptr->h_aliases[i] = cp; 156 cp += n; 157 } 158 hptr->h_aliases[i] = NULL; 159 160 return (0); 161} 162 163#ifdef NS_CACHING 164static int 165host_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata) 166{ 167 res_state statp; 168 u_long res_options; 169 170 const int op_id = 1; 171 char *str; 172 int len, type; 173 174 size_t desired_size, size; 175 enum nss_lookup_type lookup_type; 176 char *p; 177 int res = NS_UNAVAIL; 178 179 statp = __res_state(); 180 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES | 181 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6); 182 183 lookup_type = (enum nss_lookup_type)cache_mdata; 184 switch (lookup_type) { 185 case nss_lt_name: 186 str = va_arg(ap, char *); 187 type = va_arg(ap, int); 188 189 size = strlen(str); 190 desired_size = sizeof(res_options) + sizeof(int) + 191 sizeof(enum nss_lookup_type) + sizeof(int) + size + 1; 192 193 if (desired_size > *buffer_size) { 194 res = NS_RETURN; 195 goto fin; 196 } 197 198 p = buffer; 199 200 memcpy(p, &res_options, sizeof(res_options)); 201 p += sizeof(res_options); 202 203 memcpy(p, &op_id, sizeof(int)); 204 p += sizeof(int); 205 206 memcpy(p, &lookup_type, sizeof(enum nss_lookup_type)); 207 p += sizeof(int); 208 209 memcpy(p, &type, sizeof(int)); 210 p += sizeof(int); 211 212 memcpy(p, str, size + 1); 213 214 res = NS_SUCCESS; 215 break; 216 case nss_lt_id: 217 str = va_arg(ap, char *); 218 len = va_arg(ap, int); 219 type = va_arg(ap, int); 220 221 desired_size = sizeof(res_options) + sizeof(int) + 222 sizeof(enum nss_lookup_type) + sizeof(int) * 2 + len; 223 224 if (desired_size > *buffer_size) { 225 res = NS_RETURN; 226 goto fin; 227 } 228 229 p = buffer; 230 memcpy(p, &res_options, sizeof(res_options)); 231 p += sizeof(res_options); 232 233 memcpy(p, &op_id, sizeof(int)); 234 p += sizeof(int); 235 236 memcpy(p, &lookup_type, sizeof(enum nss_lookup_type)); 237 p += sizeof(int); 238 239 memcpy(p, &type, sizeof(int)); 240 p += sizeof(int); 241 242 memcpy(p, &len, sizeof(int)); 243 p += sizeof(int); 244 245 memcpy(p, str, len); 246 247 res = NS_SUCCESS; 248 break; 249 default: 250 /* should be unreachable */ 251 return (NS_UNAVAIL); 252 } 253 254fin: 255 *buffer_size = desired_size; 256 return (res); 257} 258 259static int 260host_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap, 261 void *cache_mdata) 262{ 263 char *str; 264 int len, type; 265 struct hostent *ht; 266 267 struct hostent new_ht; 268 size_t desired_size, aliases_size, addr_size, size; 269 char *p, **iter; 270 271 switch ((enum nss_lookup_type)cache_mdata) { 272 case nss_lt_name: 273 str = va_arg(ap, char *); 274 type = va_arg(ap, int); 275 break; 276 case nss_lt_id: 277 str = va_arg(ap, char *); 278 len = va_arg(ap, int); 279 type = va_arg(ap, int); 280 break; 281 default: 282 /* should be unreachable */ 283 return (NS_UNAVAIL); 284 } 285 ht = va_arg(ap, struct hostent *); 286 287 desired_size = _ALIGNBYTES + sizeof(struct hostent) + sizeof(char *); 288 if (ht->h_name != NULL) 289 desired_size += strlen(ht->h_name) + 1; 290 291 if (ht->h_aliases != NULL) { 292 aliases_size = 0; 293 for (iter = ht->h_aliases; *iter; ++iter) { 294 desired_size += strlen(*iter) + 1; 295 ++aliases_size; 296 } 297 298 desired_size += _ALIGNBYTES + 299 (aliases_size + 1) * sizeof(char *); 300 } 301 302 if (ht->h_addr_list != NULL) { 303 addr_size = 0; 304 for (iter = ht->h_addr_list; *iter; ++iter) 305 ++addr_size; 306 307 desired_size += addr_size * _ALIGN(ht->h_length); 308 desired_size += _ALIGNBYTES + (addr_size + 1) * sizeof(char *); 309 } 310 311 if (desired_size > *buffer_size) { 312 /* this assignment is here for future use */ 313 *buffer_size = desired_size; 314 return (NS_RETURN); 315 } 316 317 memcpy(&new_ht, ht, sizeof(struct hostent)); 318 memset(buffer, 0, desired_size); 319 320 *buffer_size = desired_size; 321 p = buffer + sizeof(struct hostent) + sizeof(char *); 322 memcpy(buffer + sizeof(struct hostent), &p, sizeof(char *)); 323 p = (char *)_ALIGN(p); 324 325 if (new_ht.h_name != NULL) { 326 size = strlen(new_ht.h_name); 327 memcpy(p, new_ht.h_name, size); 328 new_ht.h_name = p; 329 p += size + 1; 330 } 331 332 if (new_ht.h_aliases != NULL) { 333 p = (char *)_ALIGN(p); 334 memcpy(p, new_ht.h_aliases, sizeof(char *) * aliases_size); 335 new_ht.h_aliases = (char **)p; 336 p += sizeof(char *) * (aliases_size + 1); 337 338 for (iter = new_ht.h_aliases; *iter; ++iter) { 339 size = strlen(*iter); 340 memcpy(p, *iter, size); 341 *iter = p; 342 p += size + 1; 343 } 344 } 345 346 if (new_ht.h_addr_list != NULL) { 347 p = (char *)_ALIGN(p); 348 memcpy(p, new_ht.h_addr_list, sizeof(char *) * addr_size); 349 new_ht.h_addr_list = (char **)p; 350 p += sizeof(char *) * (addr_size + 1); 351 352 size = _ALIGN(new_ht.h_length); 353 for (iter = new_ht.h_addr_list; *iter; ++iter) { 354 memcpy(p, *iter, size); 355 *iter = p; 356 p += size + 1; 357 } 358 } 359 memcpy(buffer, &new_ht, sizeof(struct hostent)); 360 return (NS_SUCCESS); 361} 362 363static int 364host_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap, 365 void *cache_mdata) 366{ 367 char *str; 368 int len, type; 369 struct hostent *ht; 370 371 char *p; 372 char **iter; 373 char *orig_buf; 374 size_t orig_buf_size; 375 376 switch ((enum nss_lookup_type)cache_mdata) { 377 case nss_lt_name: 378 str = va_arg(ap, char *); 379 type = va_arg(ap, int); 380 break; 381 case nss_lt_id: 382 str = va_arg(ap, char *); 383 len = va_arg(ap, int); 384 type = va_arg(ap, int); 385 break; 386 default: 387 /* should be unreachable */ 388 return (NS_UNAVAIL); 389 } 390 391 ht = va_arg(ap, struct hostent *); 392 orig_buf = va_arg(ap, char *); 393 orig_buf_size = va_arg(ap, size_t); 394 395 if (orig_buf_size < 396 buffer_size - sizeof(struct hostent) - sizeof(char *)) { 397 errno = ERANGE; 398 return (NS_RETURN); 399 } 400 401 memcpy(ht, buffer, sizeof(struct hostent)); 402 memcpy(&p, buffer + sizeof(struct hostent), sizeof(char *)); 403 404 orig_buf = (char *)_ALIGN(orig_buf); 405 memcpy(orig_buf, buffer + sizeof(struct hostent) + sizeof(char *) + 406 _ALIGN(p) - (size_t)p, 407 buffer_size - sizeof(struct hostent) - sizeof(char *) - 408 _ALIGN(p) + (size_t)p); 409 p = (char *)_ALIGN(p); 410 411 NS_APPLY_OFFSET(ht->h_name, orig_buf, p, char *); 412 if (ht->h_aliases != NULL) { 413 NS_APPLY_OFFSET(ht->h_aliases, orig_buf, p, char **); 414 415 for (iter = ht->h_aliases; *iter; ++iter) 416 NS_APPLY_OFFSET(*iter, orig_buf, p, char *); 417 } 418 419 if (ht->h_addr_list != NULL) { 420 NS_APPLY_OFFSET(ht->h_addr_list, orig_buf, p, char **); 421 422 for (iter = ht->h_addr_list; *iter; ++iter) 423 NS_APPLY_OFFSET(*iter, orig_buf, p, char *); 424 } 425 426 *((struct hostent **)retval) = ht; 427 return (NS_SUCCESS); 428} 429#endif /* NS_CACHING */ 430 431static int 432fakeaddr(const char *name, int af, struct hostent *hp, char *buf, 433 size_t buflen, res_state statp) 434{ 435 struct hostent_data *hed; 436 struct hostent he; 437 438 if ((hed = __hostent_data_init()) == NULL) { 439 errno = ENOMEM; 440 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 441 return (-1); 442 } 443 444 if ((af != AF_INET || 445 inet_aton(name, (struct in_addr *)hed->host_addr) != 1) && 446 inet_pton(af, name, hed->host_addr) != 1) { 447 RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); 448 return (-1); 449 } 450 strncpy(hed->hostbuf, name, MAXDNAME); 451 hed->hostbuf[MAXDNAME] = '\0'; 452 if (af == AF_INET && (statp->options & RES_USE_INET6) != 0U) { 453 _map_v4v6_address((char *)hed->host_addr, 454 (char *)hed->host_addr); 455 af = AF_INET6; 456 } 457 he.h_addrtype = af; 458 switch(af) { 459 case AF_INET: 460 he.h_length = NS_INADDRSZ; 461 break; 462 case AF_INET6: 463 he.h_length = NS_IN6ADDRSZ; 464 break; 465 default: 466 errno = EAFNOSUPPORT; 467 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 468 return (-1); 469 } 470 he.h_name = hed->hostbuf; 471 he.h_aliases = hed->host_aliases; 472 hed->host_aliases[0] = NULL; 473 hed->h_addr_ptrs[0] = (char *)hed->host_addr; 474 hed->h_addr_ptrs[1] = NULL; 475 he.h_addr_list = hed->h_addr_ptrs; 476 RES_SET_H_ERRNO(statp, NETDB_SUCCESS); 477 return (__copy_hostent(&he, hp, buf, buflen)); 478} 479 480int 481gethostbyname_r(const char *name, struct hostent *he, char *buffer, 482 size_t buflen, struct hostent **result, int *h_errnop) 483{ 484 res_state statp; 485 486 statp = __res_state(); 487 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 488 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 489 return (-1); 490 } 491 if (statp->options & RES_USE_INET6) { 492 if (fakeaddr(name, AF_INET, he, buffer, buflen, statp) == 0) { 493 *result = he; 494 return (0); 495 } 496 if (gethostbyname_internal(name, AF_INET6, he, buffer, buflen, 497 result, h_errnop, statp) == 0) 498 return (0); 499 } 500 return (gethostbyname_internal(name, AF_INET, he, buffer, buflen, 501 result, h_errnop, statp)); 502} 503 504int 505gethostbyname2_r(const char *name, int af, struct hostent *he, char *buffer, 506 size_t buflen, struct hostent **result, int *h_errnop) 507{ 508 res_state statp; 509 510 statp = __res_state(); 511 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 512 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 513 return (-1); 514 } 515 return (gethostbyname_internal(name, af, he, buffer, buflen, result, 516 h_errnop, statp)); 517} 518 519int 520gethostbyname_internal(const char *name, int af, struct hostent *hp, char *buf, 521 size_t buflen, struct hostent **result, int *h_errnop, res_state statp) 522{ 523 const char *cp; 524 int rval, ret_errno; 525 char abuf[MAXDNAME]; 526 527#ifdef NS_CACHING 528 static const nss_cache_info cache_info = 529 NS_COMMON_CACHE_INFO_INITIALIZER( 530 hosts, (void *)nss_lt_name, 531 host_id_func, host_marshal_func, host_unmarshal_func); 532#endif 533 static const ns_dtab dtab[] = { 534 NS_FILES_CB(_ht_gethostbyname, NULL) 535 { NSSRC_DNS, _dns_gethostbyname, NULL }, 536 NS_NIS_CB(_nis_gethostbyname, NULL) /* force -DHESIOD */ 537#ifdef NS_CACHING 538 NS_CACHE_CB(&cache_info) 539#endif 540 { 0 } 541 }; 542 543 switch (af) { 544 case AF_INET: 545 case AF_INET6: 546 break; 547 default: 548 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 549 *h_errnop = statp->res_h_errno; 550 errno = EAFNOSUPPORT; 551 return (-1); 552 } 553 554 /* 555 * if there aren't any dots, it could be a user-level alias. 556 * this is also done in res_query() since we are not the only 557 * function that looks up host names. 558 */ 559 if (!strchr(name, '.') && 560 (cp = res_hostalias(statp, name, abuf, sizeof abuf))) 561 name = cp; 562 563 if (fakeaddr(name, af, hp, buf, buflen, statp) == 0) { 564 *result = hp; 565 return (0); 566 } 567 568 rval = _nsdispatch((void *)result, dtab, NSDB_HOSTS, 569 "gethostbyname2_r", default_src, name, af, hp, buf, buflen, 570 &ret_errno, h_errnop); 571 572 return ((rval == NS_SUCCESS) ? 0 : -1); 573} 574 575int 576gethostbyaddr_r(const char *addr, int len, int af, struct hostent *hp, 577 char *buf, size_t buflen, struct hostent **result, int *h_errnop) 578{ 579 const u_char *uaddr = (const u_char *)addr; 580 const struct in6_addr *addr6; 581 socklen_t size; 582 int rval, ret_errno; 583 res_state statp; 584 585#ifdef NS_CACHING 586 static const nss_cache_info cache_info = 587 NS_COMMON_CACHE_INFO_INITIALIZER( 588 hosts, (void *)nss_lt_id, 589 host_id_func, host_marshal_func, host_unmarshal_func); 590#endif 591 static const ns_dtab dtab[] = { 592 NS_FILES_CB(_ht_gethostbyaddr, NULL) 593 { NSSRC_DNS, _dns_gethostbyaddr, NULL }, 594 NS_NIS_CB(_nis_gethostbyaddr, NULL) /* force -DHESIOD */ 595#ifdef NS_CACHING 596 NS_CACHE_CB(&cache_info) 597#endif 598 { 0 } 599 }; 600 601 statp = __res_state(); 602 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { 603 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 604 *h_errnop = statp->res_h_errno; 605 return (-1); 606 } 607 608 if (af == AF_INET6 && len == NS_IN6ADDRSZ) { 609 addr6 = (const struct in6_addr *)(const void *)uaddr; 610 if (IN6_IS_ADDR_LINKLOCAL(addr6)) { 611 RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); 612 *h_errnop = statp->res_h_errno; 613 return (-1); 614 } 615 if (IN6_IS_ADDR_V4MAPPED(addr6) || 616 IN6_IS_ADDR_V4COMPAT(addr6)) { 617 /* Unmap. */ 618 uaddr += NS_IN6ADDRSZ - NS_INADDRSZ; 619 af = AF_INET; 620 len = NS_INADDRSZ; 621 } 622 } 623 switch (af) { 624 case AF_INET: 625 size = NS_INADDRSZ; 626 break; 627 case AF_INET6: 628 size = NS_IN6ADDRSZ; 629 break; 630 default: 631 errno = EAFNOSUPPORT; 632 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 633 *h_errnop = statp->res_h_errno; 634 return (-1); 635 } 636 if (size != len) { 637 errno = EINVAL; 638 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 639 *h_errnop = statp->res_h_errno; 640 return (-1); 641 } 642 643 rval = _nsdispatch((void *)result, dtab, NSDB_HOSTS, 644 "gethostbyaddr_r", default_src, uaddr, len, af, hp, buf, buflen, 645 &ret_errno, h_errnop); 646 647 return ((rval == NS_SUCCESS) ? 0 : -1); 648} 649 650struct hostent * 651gethostbyname(const char *name) 652{ 653 struct hostdata *hd; 654 struct hostent *rval; 655 int ret_h_errno; 656 657 if ((hd = __hostdata_init()) == NULL) 658 return (NULL); 659 if (gethostbyname_r(name, &hd->host, hd->data, sizeof(hd->data), &rval, 660 &ret_h_errno) != 0) 661 return (NULL); 662 return (rval); 663} 664 665struct hostent * 666gethostbyname2(const char *name, int af) 667{ 668 struct hostdata *hd; 669 struct hostent *rval; 670 int ret_h_errno; 671 672 if ((hd = __hostdata_init()) == NULL) 673 return (NULL); 674 if (gethostbyname2_r(name, af, &hd->host, hd->data, sizeof(hd->data), 675 &rval, &ret_h_errno) != 0) 676 return (NULL); 677 return (rval); 678} 679 680struct hostent * 681gethostbyaddr(const char *addr, int len, int af) 682{ 683 struct hostdata *hd; 684 struct hostent *rval; 685 int ret_h_errno; 686 687 if ((hd = __hostdata_init()) == NULL) 688 return (NULL); 689 if (gethostbyaddr_r(addr, len, af, &hd->host, hd->data, 690 sizeof(hd->data), &rval, &ret_h_errno) != 0) 691 return (NULL); 692 return (rval); 693} 694 695void 696sethostent(int stayopen) 697{ 698 struct hostent_data *hed; 699 700 if ((hed = __hostent_data_init()) == NULL) 701 return; 702 _sethosthtent(stayopen, hed); 703 _sethostdnsent(stayopen); 704} 705 706void 707endhostent(void) 708{ 709 struct hostent_data *hed; 710 711 if ((hed = __hostent_data_init()) == NULL) 712 return; 713 _endhosthtent(hed); 714 _endhostdnsent(); 715} 716