1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * $Id: hostip.c,v 1.214 2008-11-06 17:19:57 yangtse Exp $
22 ***************************************************************************/
23
24 #include "setup.h"
25
26 #include <string.h>
27
28 #ifdef NEED_MALLOC_H
29 #include <malloc.h>
30 #endif
31 #ifdef HAVE_SYS_SOCKET_H
32 #include <sys/socket.h>
33 #endif
34 #ifdef HAVE_NETINET_IN_H
35 #include <netinet/in.h>
36 #endif
37 #ifdef HAVE_NETDB_H
38 #include <netdb.h>
39 #endif
40 #ifdef HAVE_ARPA_INET_H
41 #include <arpa/inet.h>
42 #endif
43 #ifdef HAVE_STDLIB_H
44 #include <stdlib.h> /* required for free() prototypes */
45 #endif
46 #ifdef HAVE_UNISTD_H
47 #include <unistd.h> /* for the close() proto */
48 #endif
49 #ifdef VMS
50 #include <in.h>
51 #include <inet.h>
52 #include <stdlib.h>
53 #endif
54
55 #ifdef HAVE_SETJMP_H
56 #include <setjmp.h>
57 #endif
58 #ifdef HAVE_SIGNAL_H
59 #include <signal.h>
60 #endif
61
62 #ifdef HAVE_PROCESS_H
63 #include <process.h>
64 #endif
65
66 #include "urldata.h"
67 #include "sendf.h"
68 #include "hostip.h"
69 #include "hash.h"
70 #include "share.h"
71 #include "strerror.h"
72 #include "url.h"
73 #include "inet_ntop.h"
74
75 #define _MPRINTF_REPLACE /* use our functions only */
76 #include <curl/mprintf.h>
77
78 #include "memory.h"
79 /* The last #include file should be: */
80 #include "memdebug.h"
81
82 #if defined(HAVE_ALARM) && defined(SIGALRM) && defined(HAVE_SIGSETJMP) \
83 && !defined(USE_ARES)
84 /* alarm-based timeouts can only be used with all the dependencies satisfied */
85 #define USE_ALARM_TIMEOUT
86 #endif
87
88 /*
89 * hostip.c explained
90 * ==================
91 *
92 * The main COMPILE-TIME DEFINES to keep in mind when reading the host*.c
93 * source file are these:
94 *
95 * CURLRES_IPV6 - this host has getaddrinfo() and family, and thus we use
96 * that. The host may not be able to resolve IPv6, but we don't really have to
97 * take that into account. Hosts that aren't IPv6-enabled have CURLRES_IPV4
98 * defined.
99 *
100 * CURLRES_ARES - is defined if libcurl is built to use c-ares for
101 * asynchronous name resolves. This can be Windows or *nix.
102 *
103 * CURLRES_THREADED - is defined if libcurl is built to run under (native)
104 * Windows, and then the name resolve will be done in a new thread, and the
105 * supported API will be the same as for ares-builds.
106 *
107 * If any of the two previous are defined, CURLRES_ASYNCH is defined too. If
108 * libcurl is not built to use an asynchronous resolver, CURLRES_SYNCH is
109 * defined.
110 *
111 * The host*.c sources files are split up like this:
112 *
113 * hostip.c - method-independent resolver functions and utility functions
114 * hostasyn.c - functions for asynchronous name resolves
115 * hostsyn.c - functions for synchronous name resolves
116 * hostares.c - functions for ares-using name resolves
117 * hostthre.c - functions for threaded name resolves
118 * hostip4.c - ipv4-specific functions
119 * hostip6.c - ipv6-specific functions
120 *
121 * The hostip.h is the united header file for all this. It defines the
122 * CURLRES_* defines based on the config*.h and setup.h defines.
123 */
124
125 /* These two symbols are for the global DNS cache */
126 static struct curl_hash hostname_cache;
127 static int host_cache_initialized;
128
129 static void freednsentry(void *freethis);
130
131 /*
132 * Curl_global_host_cache_init() initializes and sets up a global DNS cache.
133 * Global DNS cache is general badness. Do not use. This will be removed in
134 * a future version. Use the share interface instead!
135 *
136 * Returns a struct curl_hash pointer on success, NULL on failure.
137 */
Curl_global_host_cache_init(void)138 struct curl_hash *Curl_global_host_cache_init(void)
139 {
140 int rc = 0;
141 if(!host_cache_initialized) {
142 rc = Curl_hash_init(&hostname_cache, 7, Curl_hash_str,
143 Curl_str_key_compare, freednsentry);
144 if(!rc)
145 host_cache_initialized = 1;
146 }
147 return rc?NULL:&hostname_cache;
148 }
149
150 /*
151 * Destroy and cleanup the global DNS cache
152 */
Curl_global_host_cache_dtor(void)153 void Curl_global_host_cache_dtor(void)
154 {
155 if(host_cache_initialized) {
156 Curl_hash_clean(&hostname_cache);
157 host_cache_initialized = 0;
158 }
159 }
160
161 /*
162 * Return # of adresses in a Curl_addrinfo struct
163 */
Curl_num_addresses(const Curl_addrinfo * addr)164 int Curl_num_addresses(const Curl_addrinfo *addr)
165 {
166 int i = 0;
167 while(addr) {
168 addr = addr->ai_next;
169 i++;
170 }
171 return i;
172 }
173
174 /*
175 * Curl_printable_address() returns a printable version of the 1st address
176 * given in the 'ai' argument. The result will be stored in the buf that is
177 * bufsize bytes big.
178 *
179 * If the conversion fails, it returns NULL.
180 */
181 const char *
Curl_printable_address(const Curl_addrinfo * ai,char * buf,size_t bufsize)182 Curl_printable_address(const Curl_addrinfo *ai, char *buf, size_t bufsize)
183 {
184 const struct sockaddr_in *sa4;
185 const struct in_addr *ipaddr4;
186 #ifdef ENABLE_IPV6
187 const struct sockaddr_in6 *sa6;
188 const struct in6_addr *ipaddr6;
189 #endif
190
191 switch (ai->ai_family) {
192 case AF_INET:
193 sa4 = (const void *)ai->ai_addr;
194 ipaddr4 = &sa4->sin_addr;
195 return Curl_inet_ntop(ai->ai_family, (const void *)ipaddr4, buf, bufsize);
196 #ifdef ENABLE_IPV6
197 case AF_INET6:
198 sa6 = (const void *)ai->ai_addr;
199 ipaddr6 = &sa6->sin6_addr;
200 return Curl_inet_ntop(ai->ai_family, (const void *)ipaddr6, buf, bufsize);
201 #endif
202 default:
203 break;
204 }
205 return NULL;
206 }
207
208 /*
209 * Return a hostcache id string for the providing host + port, to be used by
210 * the DNS caching.
211 */
212 static char *
create_hostcache_id(const char * server,int port)213 create_hostcache_id(const char *server, int port)
214 {
215 /* create and return the new allocated entry */
216 return aprintf("%s:%d", server, port);
217 }
218
219 struct hostcache_prune_data {
220 long cache_timeout;
221 time_t now;
222 };
223
224 /*
225 * This function is set as a callback to be called for every entry in the DNS
226 * cache when we want to prune old unused entries.
227 *
228 * Returning non-zero means remove the entry, return 0 to keep it in the
229 * cache.
230 */
231 static int
hostcache_timestamp_remove(void * datap,void * hc)232 hostcache_timestamp_remove(void *datap, void *hc)
233 {
234 struct hostcache_prune_data *data =
235 (struct hostcache_prune_data *) datap;
236 struct Curl_dns_entry *c = (struct Curl_dns_entry *) hc;
237
238 if((data->now - c->timestamp < data->cache_timeout) ||
239 c->inuse) {
240 /* please don't remove */
241 return 0;
242 }
243
244 /* fine, remove */
245 return 1;
246 }
247
248 /*
249 * Prune the DNS cache. This assumes that a lock has already been taken.
250 */
251 static void
hostcache_prune(struct curl_hash * hostcache,long cache_timeout,time_t now)252 hostcache_prune(struct curl_hash *hostcache, long cache_timeout, time_t now)
253 {
254 struct hostcache_prune_data user;
255
256 user.cache_timeout = cache_timeout;
257 user.now = now;
258
259 Curl_hash_clean_with_criterium(hostcache,
260 (void *) &user,
261 hostcache_timestamp_remove);
262 }
263
264 /*
265 * Library-wide function for pruning the DNS cache. This function takes and
266 * returns the appropriate locks.
267 */
Curl_hostcache_prune(struct SessionHandle * data)268 void Curl_hostcache_prune(struct SessionHandle *data)
269 {
270 time_t now;
271
272 if((data->set.dns_cache_timeout == -1) || !data->dns.hostcache)
273 /* cache forever means never prune, and NULL hostcache means
274 we can't do it */
275 return;
276
277 if(data->share)
278 Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
279
280 time(&now);
281
282 /* Remove outdated and unused entries from the hostcache */
283 hostcache_prune(data->dns.hostcache,
284 data->set.dns_cache_timeout,
285 now);
286
287 if(data->share)
288 Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
289 }
290
291 /*
292 * Check if the entry should be pruned. Assumes a locked cache.
293 */
294 static int
remove_entry_if_stale(struct SessionHandle * data,struct Curl_dns_entry * dns)295 remove_entry_if_stale(struct SessionHandle *data, struct Curl_dns_entry *dns)
296 {
297 struct hostcache_prune_data user;
298
299 if( !dns || (data->set.dns_cache_timeout == -1) || !data->dns.hostcache)
300 /* cache forever means never prune, and NULL hostcache means
301 we can't do it */
302 return 0;
303
304 time(&user.now);
305 user.cache_timeout = data->set.dns_cache_timeout;
306
307 if( !hostcache_timestamp_remove(&user,dns) )
308 return 0;
309
310 Curl_hash_clean_with_criterium(data->dns.hostcache,
311 (void *) &user,
312 hostcache_timestamp_remove);
313
314 return 1;
315 }
316
317
318 #ifdef HAVE_SIGSETJMP
319 /* Beware this is a global and unique instance. This is used to store the
320 return address that we can jump back to from inside a signal handler. This
321 is not thread-safe stuff. */
322 sigjmp_buf curl_jmpenv;
323 #endif
324
325
326 /*
327 * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache.
328 *
329 * When calling Curl_resolv() has resulted in a response with a returned
330 * address, we call this function to store the information in the dns
331 * cache etc
332 *
333 * Returns the Curl_dns_entry entry pointer or NULL if the storage failed.
334 */
335 struct Curl_dns_entry *
Curl_cache_addr(struct SessionHandle * data,Curl_addrinfo * addr,const char * hostname,int port)336 Curl_cache_addr(struct SessionHandle *data,
337 Curl_addrinfo *addr,
338 const char *hostname,
339 int port)
340 {
341 char *entry_id;
342 size_t entry_len;
343 struct Curl_dns_entry *dns;
344 struct Curl_dns_entry *dns2;
345 time_t now;
346
347 /* Create an entry id, based upon the hostname and port */
348 entry_id = create_hostcache_id(hostname, port);
349 /* If we can't create the entry id, fail */
350 if(!entry_id)
351 return NULL;
352 entry_len = strlen(entry_id);
353
354 /* Create a new cache entry */
355 dns = calloc(sizeof(struct Curl_dns_entry), 1);
356 if(!dns) {
357 free(entry_id);
358 return NULL;
359 }
360
361 dns->inuse = 0; /* init to not used */
362 dns->addr = addr; /* this is the address(es) */
363
364 /* Store the resolved data in our DNS cache. This function may return a
365 pointer to an existing struct already present in the hash, and it may
366 return the same argument we pass in. Make no assumptions. */
367 dns2 = Curl_hash_add(data->dns.hostcache, entry_id, entry_len+1,
368 (void *)dns);
369 if(!dns2) {
370 /* Major badness, run away. */
371 free(dns);
372 free(entry_id);
373 return NULL;
374 }
375 time(&now);
376 dns = dns2;
377
378 dns->timestamp = now; /* used now */
379 dns->inuse++; /* mark entry as in-use */
380
381 /* free the allocated entry_id again */
382 free(entry_id);
383
384 return dns;
385 }
386
387 /*
388 * Curl_resolv() is the main name resolve function within libcurl. It resolves
389 * a name and returns a pointer to the entry in the 'entry' argument (if one
390 * is provided). This function might return immediately if we're using asynch
391 * resolves. See the return codes.
392 *
393 * The cache entry we return will get its 'inuse' counter increased when this
394 * function is used. You MUST call Curl_resolv_unlock() later (when you're
395 * done using this struct) to decrease the counter again.
396 *
397 * Return codes:
398 *
399 * CURLRESOLV_ERROR (-1) = error, no pointer
400 * CURLRESOLV_RESOLVED (0) = OK, pointer provided
401 * CURLRESOLV_PENDING (1) = waiting for response, no pointer
402 */
403
Curl_resolv(struct connectdata * conn,const char * hostname,int port,struct Curl_dns_entry ** entry)404 int Curl_resolv(struct connectdata *conn,
405 const char *hostname,
406 int port,
407 struct Curl_dns_entry **entry)
408 {
409 char *entry_id = NULL;
410 struct Curl_dns_entry *dns = NULL;
411 size_t entry_len;
412 struct SessionHandle *data = conn->data;
413 CURLcode result;
414 int rc = CURLRESOLV_ERROR; /* default to failure */
415
416 *entry = NULL;
417
418 /* Create an entry id, based upon the hostname and port */
419 entry_id = create_hostcache_id(hostname, port);
420 /* If we can't create the entry id, fail */
421 if(!entry_id)
422 return rc;
423
424 entry_len = strlen(entry_id);
425
426 if(data->share)
427 Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
428
429 /* See if its already in our dns cache */
430 dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
431
432 /* See whether the returned entry is stale. Done before we release lock */
433 if( remove_entry_if_stale(data, dns) )
434 dns = NULL; /* the memory deallocation is being handled by the hash */
435
436 if(dns) {
437 dns->inuse++; /* we use it! */
438 rc = CURLRESOLV_RESOLVED;
439 }
440
441 if(data->share)
442 Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
443
444 /* free the allocated entry_id again */
445 free(entry_id);
446
447 if(!dns) {
448 /* The entry was not in the cache. Resolve it to IP address */
449
450 Curl_addrinfo *addr;
451 int respwait;
452
453 /* Check what IP specifics the app has requested and if we can provide it.
454 * If not, bail out. */
455 if(!Curl_ipvalid(data))
456 return CURLRESOLV_ERROR;
457
458 /* If Curl_getaddrinfo() returns NULL, 'respwait' might be set to a
459 non-zero value indicating that we need to wait for the response to the
460 resolve call */
461 addr = Curl_getaddrinfo(conn, hostname, port, &respwait);
462
463 if(!addr) {
464 if(respwait) {
465 /* the response to our resolve call will come asynchronously at
466 a later time, good or bad */
467 /* First, check that we haven't received the info by now */
468 result = Curl_is_resolved(conn, &dns);
469 if(result) /* error detected */
470 return CURLRESOLV_ERROR;
471 if(dns)
472 rc = CURLRESOLV_RESOLVED; /* pointer provided */
473 else
474 rc = CURLRESOLV_PENDING; /* no info yet */
475 }
476 }
477 else {
478 if(data->share)
479 Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
480
481 /* we got a response, store it in the cache */
482 dns = Curl_cache_addr(data, addr, hostname, port);
483
484 if(data->share)
485 Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
486
487 if(!dns)
488 /* returned failure, bail out nicely */
489 Curl_freeaddrinfo(addr);
490 else
491 rc = CURLRESOLV_RESOLVED;
492 }
493 }
494
495 *entry = dns;
496
497 return rc;
498 }
499
500 #ifdef USE_ALARM_TIMEOUT
501 /*
502 * This signal handler jumps back into the main libcurl code and continues
503 * execution. This effectively causes the remainder of the application to run
504 * within a signal handler which is nonportable and could lead to problems.
505 */
506 static
alarmfunc(int sig)507 RETSIGTYPE alarmfunc(int sig)
508 {
509 /* this is for "-ansi -Wall -pedantic" to stop complaining! (rabe) */
510 (void)sig;
511 siglongjmp(curl_jmpenv, 1);
512 return;
513 }
514 #endif /* USE_ALARM_TIMEOUT */
515
516 /*
517 * Curl_resolv_timeout() is the same as Curl_resolv() but specifies a
518 * timeout. This function might return immediately if we're using asynch
519 * resolves. See the return codes.
520 *
521 * The cache entry we return will get its 'inuse' counter increased when this
522 * function is used. You MUST call Curl_resolv_unlock() later (when you're
523 * done using this struct) to decrease the counter again.
524 *
525 * If built with a synchronous resolver and use of signals is not
526 * disabled by the application, then a nonzero timeout will cause a
527 * timeout after the specified number of milliseconds. Otherwise, timeout
528 * is ignored.
529 *
530 * Return codes:
531 *
532 * CURLRESOLV_TIMEDOUT(-2) = warning, time too short or previous alarm expired
533 * CURLRESOLV_ERROR (-1) = error, no pointer
534 * CURLRESOLV_RESOLVED (0) = OK, pointer provided
535 * CURLRESOLV_PENDING (1) = waiting for response, no pointer
536 */
537
Curl_resolv_timeout(struct connectdata * conn,const char * hostname,int port,struct Curl_dns_entry ** entry,long timeoutms)538 int Curl_resolv_timeout(struct connectdata *conn,
539 const char *hostname,
540 int port,
541 struct Curl_dns_entry **entry,
542 long timeoutms)
543 {
544 #ifdef USE_ALARM_TIMEOUT
545 #ifdef HAVE_SIGACTION
546 struct sigaction keep_sigact; /* store the old struct here */
547 bool keep_copysig=FALSE; /* did copy it? */
548 struct sigaction sigact;
549 #else
550 #ifdef HAVE_SIGNAL
551 void (*keep_sigact)(int); /* store the old handler here */
552 #endif /* HAVE_SIGNAL */
553 #endif /* HAVE_SIGACTION */
554 volatile long timeout;
555 unsigned int prev_alarm=0;
556 struct SessionHandle *data = conn->data;
557 #endif /* USE_ALARM_TIMEOUT */
558 int rc;
559
560 *entry = NULL;
561
562 #ifdef USE_ALARM_TIMEOUT
563 if (data->set.no_signal)
564 /* Ignore the timeout when signals are disabled */
565 timeout = 0;
566 else
567 timeout = timeoutms;
568
569 if(timeout && timeout < 1000)
570 /* The alarm() function only provides integer second resolution, so if
571 we want to wait less than one second we must bail out already now. */
572 return CURLRESOLV_TIMEDOUT;
573
574 if (timeout > 0) {
575 /* This allows us to time-out from the name resolver, as the timeout
576 will generate a signal and we will siglongjmp() from that here.
577 This technique has problems (see alarmfunc). */
578 if(sigsetjmp(curl_jmpenv, 1)) {
579 /* this is coming from a siglongjmp() after an alarm signal */
580 failf(data, "name lookup timed out");
581 return CURLRESOLV_ERROR;
582 }
583
584 /*************************************************************
585 * Set signal handler to catch SIGALRM
586 * Store the old value to be able to set it back later!
587 *************************************************************/
588 #ifdef HAVE_SIGACTION
589 sigaction(SIGALRM, NULL, &sigact);
590 keep_sigact = sigact;
591 keep_copysig = TRUE; /* yes, we have a copy */
592 sigact.sa_handler = alarmfunc;
593 #ifdef SA_RESTART
594 /* HPUX doesn't have SA_RESTART but defaults to that behaviour! */
595 sigact.sa_flags &= ~SA_RESTART;
596 #endif
597 /* now set the new struct */
598 sigaction(SIGALRM, &sigact, NULL);
599 #else /* HAVE_SIGACTION */
600 /* no sigaction(), revert to the much lamer signal() */
601 #ifdef HAVE_SIGNAL
602 keep_sigact = signal(SIGALRM, alarmfunc);
603 #endif
604 #endif /* HAVE_SIGACTION */
605
606 /* alarm() makes a signal get sent when the timeout fires off, and that
607 will abort system calls */
608 prev_alarm = alarm((unsigned int) (timeout/1000L));
609 }
610
611 #else
612 #ifndef CURLRES_ASYNCH
613 if(timeoutms)
614 infof(conn->data, "timeout on name lookup is not supported\n");
615 #else
616 (void)timeoutms; /* timeoutms not used with an async resolver */
617 #endif
618 #endif /* USE_ALARM_TIMEOUT */
619
620 /* Perform the actual name resolution. This might be interrupted by an
621 * alarm if it takes too long.
622 */
623 rc = Curl_resolv(conn, hostname, port, entry);
624
625 #ifdef USE_ALARM_TIMEOUT
626 if (timeout > 0) {
627
628 #ifdef HAVE_SIGACTION
629 if(keep_copysig) {
630 /* we got a struct as it looked before, now put that one back nice
631 and clean */
632 sigaction(SIGALRM, &keep_sigact, NULL); /* put it back */
633 }
634 #else
635 #ifdef HAVE_SIGNAL
636 /* restore the previous SIGALRM handler */
637 signal(SIGALRM, keep_sigact);
638 #endif
639 #endif /* HAVE_SIGACTION */
640
641 /* switch back the alarm() to either zero or to what it was before minus
642 the time we spent until now! */
643 if(prev_alarm) {
644 /* there was an alarm() set before us, now put it back */
645 unsigned long elapsed_ms = Curl_tvdiff(Curl_tvnow(), conn->created);
646
647 /* the alarm period is counted in even number of seconds */
648 unsigned long alarm_set = prev_alarm - elapsed_ms/1000;
649
650 if(!alarm_set ||
651 ((alarm_set >= 0x80000000) && (prev_alarm < 0x80000000)) ) {
652 /* if the alarm time-left reached zero or turned "negative" (counted
653 with unsigned values), we should fire off a SIGALRM here, but we
654 won't, and zero would be to switch it off so we never set it to
655 less than 1! */
656 alarm(1);
657 rc = CURLRESOLV_TIMEDOUT;
658 failf(data, "Previous alarm fired off!");
659 }
660 else
661 alarm((unsigned int)alarm_set);
662 }
663 else
664 alarm(0); /* just shut it off */
665 }
666 #endif /* USE_ALARM_TIMEOUT */
667
668 return rc;
669 }
670
671 /*
672 * Curl_resolv_unlock() unlocks the given cached DNS entry. When this has been
673 * made, the struct may be destroyed due to pruning. It is important that only
674 * one unlock is made for each Curl_resolv() call.
675 */
Curl_resolv_unlock(struct SessionHandle * data,struct Curl_dns_entry * dns)676 void Curl_resolv_unlock(struct SessionHandle *data, struct Curl_dns_entry *dns)
677 {
678 DEBUGASSERT(dns && (dns->inuse>0));
679
680 if(data->share)
681 Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
682
683 dns->inuse--;
684
685 if(data->share)
686 Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
687 }
688
689 /*
690 * File-internal: free a cache dns entry.
691 */
freednsentry(void * freethis)692 static void freednsentry(void *freethis)
693 {
694 struct Curl_dns_entry *p = (struct Curl_dns_entry *) freethis;
695
696 if(p) {
697 Curl_freeaddrinfo(p->addr);
698 free(p);
699 }
700 }
701
702 /*
703 * Curl_mk_dnscache() creates a new DNS cache and returns the handle for it.
704 */
Curl_mk_dnscache(void)705 struct curl_hash *Curl_mk_dnscache(void)
706 {
707 return Curl_hash_alloc(7, Curl_hash_str, Curl_str_key_compare, freednsentry);
708 }
709
710 #ifdef CURLRES_ADDRINFO_COPY
711
712 /* align on even 64bit boundaries */
713 #define MEMALIGN(x) ((x)+(8-(((unsigned long)(x))&0x7)))
714
715 /*
716 * Curl_addrinfo_copy() performs a "deep" copy of a hostent into a buffer and
717 * returns a pointer to the malloc()ed copy. You need to call free() on the
718 * returned buffer when you're done with it.
719 */
Curl_addrinfo_copy(const void * org,int port)720 Curl_addrinfo *Curl_addrinfo_copy(const void *org, int port)
721 {
722 const struct hostent *orig = org;
723
724 return Curl_he2ai(orig, port);
725 }
726 #endif /* CURLRES_ADDRINFO_COPY */
727