curl/lib/hostares.c
Daniel Stenberg e36fb1ecda Curl_wait_for_resolv() no longer disconnects on failure, but leaves that
operation to the caller. Disconnecting has the disadvantage that the conn
pointer gets completely invalidated and this is not handled on lots of places
in the code.
2005-02-08 07:36:57 +00:00

302 lines
8.5 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2004, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
***************************************************************************/
#include "setup.h"
#include <string.h>
#include <errno.h>
#define _REENTRANT
#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__)
#include <malloc.h>
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h> /* required for free() prototypes */
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h> /* for the close() proto */
#endif
#ifdef VMS
#include <in.h>
#include <inet.h>
#include <stdlib.h>
#endif
#endif
#ifdef HAVE_SETJMP_H
#include <setjmp.h>
#endif
#ifdef WIN32
#include <process.h>
#endif
#if (defined(NETWARE) && defined(__NOVELL_LIBC__))
#undef in_addr_t
#define in_addr_t unsigned long
#endif
#include "urldata.h"
#include "sendf.h"
#include "hostip.h"
#include "hash.h"
#include "share.h"
#include "strerror.h"
#include "url.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
#if defined(HAVE_INET_NTOA_R) && !defined(HAVE_INET_NTOA_R_DECL)
#include "inet_ntoa_r.h"
#endif
#include "memory.h"
/* The last #include file should be: */
#include "memdebug.h"
/***********************************************************************
* Only for ares-enabled builds
**********************************************************************/
#ifdef CURLRES_ARES
/*
* Curl_fdset() is called when someone from the outside world (using
* curl_multi_fdset()) wants to get our fd_set setup and we're talking with
* ares. The caller must make sure that this function is only called when we
* have a working ares channel.
*
* Returns: CURLE_OK always!
*/
CURLcode Curl_fdset(struct connectdata *conn,
fd_set *read_fd_set,
fd_set *write_fd_set,
int *max_fdp)
{
int max = ares_fds(conn->data->state.areschannel,
read_fd_set, write_fd_set);
*max_fdp = max;
return CURLE_OK;
}
/*
* Curl_is_resolved() is called repeatedly to check if a previous name resolve
* request has completed. It should also make sure to time-out if the
* operation seems to take too long.
*
* Returns normal CURLcode errors.
*/
CURLcode Curl_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **dns)
{
fd_set read_fds, write_fds;
struct timeval tv={0,0};
struct SessionHandle *data = conn->data;
int nfds;
FD_ZERO(&read_fds);
FD_ZERO(&write_fds);
nfds = ares_fds(data->state.areschannel, &read_fds, &write_fds);
(void)select(nfds, &read_fds, &write_fds, NULL,
(struct timeval *)&tv);
/* Call ares_process() unconditonally here, even if we simply timed out
above, as otherwise the ares name resolve won't timeout! */
ares_process(data->state.areschannel, &read_fds, &write_fds);
*dns = NULL;
if(conn->async.done) {
/* we're done, kill the ares handle */
if(!conn->async.dns) {
failf(data, "Could not resolve host: %s (%s)", conn->host.dispname,
ares_strerror(conn->async.status));
return CURLE_COULDNT_RESOLVE_HOST;
}
*dns = conn->async.dns;
}
return CURLE_OK;
}
/*
* Curl_wait_for_resolv() waits for a resolve to finish. This function should
* be avoided since using this risk getting the multi interface to "hang".
*
* If 'entry' is non-NULL, make it point to the resolved dns entry
*
* Returns CURLE_COULDNT_RESOLVE_HOST if the host was not resolved, and
* CURLE_OPERATION_TIMEDOUT if a time-out occurred.
*/
CURLcode Curl_wait_for_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
CURLcode rc=CURLE_OK;
struct SessionHandle *data = conn->data;
long timeout = CURL_TIMEOUT_RESOLVE; /* default name resolve timeout */
/* now, see if there's a connect timeout or a regular timeout to
use instead of the default one */
if(conn->data->set.connecttimeout)
timeout = conn->data->set.connecttimeout;
else if(conn->data->set.timeout)
timeout = conn->data->set.timeout;
/* We convert the number of seconds into number of milliseconds here: */
if(timeout < 2147483)
/* maximum amount of seconds that can be multiplied with 1000 and
still fit within 31 bits */
timeout *= 1000;
else
timeout = 0x7fffffff; /* ridiculous amount of time anyway */
/* Wait for the name resolve query to complete. */
while (1) {
int nfds=0;
fd_set read_fds, write_fds;
struct timeval *tvp, tv, store;
int count;
struct timeval now = Curl_tvnow();
long timediff;
store.tv_sec = (int)timeout/1000;
store.tv_usec = (timeout%1000)*1000;
FD_ZERO(&read_fds);
FD_ZERO(&write_fds);
nfds = ares_fds(data->state.areschannel, &read_fds, &write_fds);
if (nfds == 0)
/* no file descriptors means we're done waiting */
break;
tvp = ares_timeout(data->state.areschannel, &store, &tv);
count = select(nfds, &read_fds, &write_fds, NULL, tvp);
if (count < 0 && errno != EINVAL)
break;
ares_process(data->state.areschannel, &read_fds, &write_fds);
timediff = Curl_tvdiff(Curl_tvnow(), now); /* spent time */
timeout -= timediff?timediff:1; /* always deduct at least 1 */
if (timeout < 0) {
/* our timeout, so we cancel the ares operation */
ares_cancel(data->state.areschannel);
break;
}
}
/* Operation complete, if the lookup was successful we now have the entry
in the cache. */
if(entry)
*entry = conn->async.dns;
if(!conn->async.dns) {
/* a name was not resolved */
if((timeout < 0) || (conn->async.status == ARES_ETIMEOUT)) {
failf(data, "Resolving host timed out: %s", conn->host.dispname);
rc = CURLE_OPERATION_TIMEDOUT;
}
else if(conn->async.done) {
failf(data, "Could not resolve host: %s (%s)", conn->host.dispname,
ares_strerror(conn->async.status));
rc = CURLE_COULDNT_RESOLVE_HOST;
}
else
rc = CURLE_OPERATION_TIMEDOUT;
/* close the connection, since we can't return failure here without
cleaning up this connection properly */
conn->bits.close = TRUE;
}
return rc;
}
/*
* Curl_getaddrinfo() - when using ares
*
* Returns name information about the given hostname and port number. If
* successful, the 'hostent' is returned and the forth argument will point to
* memory we need to free after use. That memory *MUST* be freed with
* Curl_freeaddrinfo(), nothing else.
*/
Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
char *hostname,
int port,
int *waitp)
{
char *bufp;
struct SessionHandle *data = conn->data;
in_addr_t in = inet_addr(hostname);
*waitp = FALSE;
if (in != CURL_INADDR_NONE) {
/* This is a dotted IP address 123.123.123.123-style */
return Curl_ip2addr(in, hostname, port);
}
bufp = strdup(hostname);
if(bufp) {
Curl_safefree(conn->async.hostname);
conn->async.hostname = bufp;
conn->async.port = port;
conn->async.done = FALSE; /* not done */
conn->async.status = 0; /* clear */
conn->async.dns = NULL; /* clear */
/* areschannel is already setup in the Curl_open() function */
ares_gethostbyname(data->state.areschannel, hostname, PF_INET,
Curl_addrinfo4_callback, conn);
*waitp = TRUE; /* please wait for the response */
}
return NULL; /* no struct yet */
}
#endif /* CURLRES_ARES */