curl/lib/hostthre.c

667 строки
18 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 <stdlib.h>
#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>
#include "inet_ntop.h"
#include "memory.h"
/* The last #include file should be: */
#include "memdebug.h"
/***********************************************************************
* Only for Windows threaded name resolves builds
**********************************************************************/
#ifdef CURLRES_THREADED
/* This function is used to init a threaded resolve */
static bool init_resolve_thread(struct connectdata *conn,
const char *hostname, int port,
const Curl_addrinfo *hints);
#ifdef CURLRES_IPV4
#define THREAD_FUNC gethostbyname_thread
#define THREAD_NAME "gethostbyname_thread"
#else
#define THREAD_FUNC getaddrinfo_thread
#define THREAD_NAME "getaddrinfo_thread"
#endif
#if defined(DEBUG_THREADING_GETHOSTBYNAME) || \
defined(DEBUG_THREADING_GETADDRINFO)
/* If this is defined, provide tracing */
#define TRACE(args) \
do { trace_it("%u: ", __LINE__); trace_it args; } while (0)
static void trace_it (const char *fmt, ...)
{
static int do_trace = -1;
va_list args;
if (do_trace == -1) {
const char *env = getenv("CURL_TRACE");
do_trace = (env && atoi(env) > 0);
}
if (!do_trace)
return;
va_start (args, fmt);
vfprintf (stderr, fmt, args);
fflush (stderr);
va_end (args);
}
#else
#define TRACE(x)
#endif
#ifdef DEBUG_THREADING_GETADDRINFO
static void dump_addrinfo (struct connectdata *conn, const struct addrinfo *ai)
{
TRACE(("dump_addrinfo:\n"));
for ( ; ai; ai = ai->ai_next) {
char buf [INET6_ADDRSTRLEN];
trace_it(" fam %2d, CNAME %s, ",
ai->ai_family, ai->ai_canonname ? ai->ai_canonname : "<none>");
if (Curl_printable_address(ai, buf, sizeof(buf)))
trace_it("%s\n", buf);
else
trace_it("failed; %s\n", Curl_strerror(conn,WSAGetLastError()));
}
}
#endif
struct thread_data {
HANDLE thread_hnd;
unsigned thread_id;
DWORD thread_status;
curl_socket_t dummy_sock; /* dummy for Curl_fdset() */
FILE *stderr_file;
HANDLE mutex_waiting; /* marks that we are still waiting for a resolve */
HANDLE event_resolved; /* marks that the thread obtained the information */
#ifdef CURLRES_IPV6
struct addrinfo hints;
#endif
};
#if defined(CURLRES_IPV4)
/*
* gethostbyname_thread() resolves a name, calls the Curl_addrinfo4_callback
* and then exits.
*
* For builds without ARES/ENABLE_IPV6, create a resolver thread and wait on
* it.
*/
static unsigned __stdcall gethostbyname_thread (void *arg)
{
struct connectdata *conn = (struct connectdata*) arg;
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
struct hostent *he;
int rc = 0;
/* Duplicate the passed mutex handle.
* This allows us to use it even after the container gets destroyed
* due to a resolver timeout.
*/
HANDLE mutex_waiting = NULL;
if (!DuplicateHandle(GetCurrentProcess(), td->mutex_waiting,
GetCurrentProcess(), &mutex_waiting, 0, FALSE,
DUPLICATE_SAME_ACCESS)) {
/* failed to duplicate the mutex, no point in continuing */
return 0;
}
/* Sharing the same _iob[] element with our parent thread should
* hopefully make printouts synchronised. I'm not sure it works
* with a static runtime lib (MSVC's libc.lib).
*/
#ifndef _WIN32_WCE
*stderr = *td->stderr_file;
#endif
WSASetLastError (conn->async.status = NO_DATA); /* pending status */
he = gethostbyname (conn->async.hostname);
/* is the thread initiator still waiting for us ? */
if (WaitForSingleObject(mutex_waiting, 0) == WAIT_TIMEOUT) {
/* yes, it is */
/* Mark that we have obtained the information, and that we are
* calling back with it.
*/
SetEvent(td->event_resolved);
if (he) {
Curl_addrinfo4_callback(conn, CURL_ASYNC_SUCCESS, he);
rc = 1;
}
else {
Curl_addrinfo4_callback(conn, (int)WSAGetLastError(), NULL);
rc = 0;
}
TRACE(("Winsock-error %d, addr %s\n", conn->async.status,
he ? inet_ntoa(*(struct in_addr*)he->h_addr) : "unknown"));
}
/* clean up */
CloseHandle(mutex_waiting);
return (rc);
/* An implicit _endthreadex() here */
}
#elif defined(CURLRES_IPV6)
/*
* getaddrinfo_thread() resolves a name, calls Curl_addrinfo6_callback and then
* exits.
*
* For builds without ARES, but with ENABLE_IPV6, create a resolver thread
* and wait on it.
*/
static unsigned __stdcall getaddrinfo_thread (void *arg)
{
struct connectdata *conn = (struct connectdata*) arg;
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
struct addrinfo *res;
char service [NI_MAXSERV];
int rc;
/* Duplicate the passed mutex handle.
* This allows us to use it even after the container gets destroyed
* due to a resolver timeout.
*/
HANDLE mutex_waiting = NULL;
if (!DuplicateHandle(GetCurrentProcess(), td->mutex_waiting,
GetCurrentProcess(), &mutex_waiting, 0, FALSE,
DUPLICATE_SAME_ACCESS)) {
/* failed to duplicate the mutex, no point in continuing */
return 0;
}
*stderr = *td->stderr_file;
itoa(conn->async.port, service, 10);
WSASetLastError(conn->async.status = NO_DATA); /* pending status */
rc = getaddrinfo(conn->async.hostname, service, &td->hints, &res);
/* is the thread initiator still waiting for us ? */
if (WaitForSingleObject(mutex_waiting, 0) == WAIT_TIMEOUT) {
/* yes, it is */
/* Mark that we have obtained the information, and that we are
* calling back with it.
*/
SetEvent(td->event_resolved);
if (rc == 0) {
#ifdef DEBUG_THREADING_GETADDRINFO
dump_addrinfo (conn, res);
#endif
Curl_addrinfo6_callback(conn, CURL_ASYNC_SUCCESS, res);
}
else {
Curl_addrinfo6_callback(conn, (int)WSAGetLastError(), NULL);
TRACE(("Winsock-error %d, no address\n", conn->async.status));
}
}
/* clean up */
CloseHandle(mutex_waiting);
return (rc);
/* An implicit _endthreadex() here */
}
#endif
/*
* destroy_thread_data() cleans up async resolver data.
* Complementary of ares_destroy.
*/
static void destroy_thread_data (struct Curl_async *async)
{
if (async->hostname)
free(async->hostname);
if (async->os_specific) {
struct thread_data *td = (struct thread_data*) async->os_specific;
curl_socket_t sock = td->dummy_sock;
if (sock != CURL_SOCKET_BAD)
sclose(sock);
/* destroy the synchronization objects */
if (td->mutex_waiting)
CloseHandle(td->mutex_waiting);
if (td->event_resolved)
CloseHandle(td->event_resolved);
free(async->os_specific);
}
async->hostname = NULL;
async->os_specific = NULL;
}
/*
* init_resolve_thread() starts a new thread that performs the actual
* resolve. This function returns before the resolve is done.
*
* Returns FALSE in case of failure, otherwise TRUE.
*/
static bool init_resolve_thread (struct connectdata *conn,
const char *hostname, int port,
const Curl_addrinfo *hints)
{
struct thread_data *td = calloc(sizeof(*td), 1);
if (!td) {
SetLastError(ENOMEM);
return FALSE;
}
Curl_safefree(conn->async.hostname);
conn->async.hostname = strdup(hostname);
if (!conn->async.hostname) {
free(td);
SetLastError(ENOMEM);
return FALSE;
}
conn->async.port = port;
conn->async.done = FALSE;
conn->async.status = 0;
conn->async.dns = NULL;
conn->async.os_specific = (void*) td;
td->dummy_sock = CURL_SOCKET_BAD;
/* Create the mutex used to inform the resolver thread that we're
* still waiting, and take initial ownership.
*/
td->mutex_waiting = CreateMutex(NULL, TRUE, NULL);
if (td->mutex_waiting == NULL) {
destroy_thread_data(&conn->async);
SetLastError(EAGAIN);
return FALSE;
}
/* Create the event that the thread uses to inform us that it's
* done resolving. Do not signal it.
*/
td->event_resolved = CreateEvent(NULL, TRUE, FALSE, NULL);
if (td->event_resolved == NULL) {
destroy_thread_data(&conn->async);
SetLastError(EAGAIN);
return FALSE;
}
td->stderr_file = stderr;
#ifdef _WIN32_WCE
td->thread_hnd=(HANDLE) CreateThread(NULL,0,(LPTHREAD_START_ROUTINE) THREAD_FUNC,conn,0,&td->thread_id);
#else
td->thread_hnd = (HANDLE) _beginthreadex(NULL, 0, THREAD_FUNC,
conn, 0, &td->thread_id);
#endif
#ifdef CURLRES_IPV6
curlassert(hints);
td->hints = *hints;
#else
(void) hints;
#endif
if (!td->thread_hnd) {
SetLastError(errno);
TRACE(("_beginthreadex() failed; %s\n", Curl_strerror(conn,errno)));
destroy_thread_data(&conn->async);
return FALSE;
}
/* This socket is only to keep Curl_fdset() and select() happy; should never
* become signalled for read/write since it's unbound but Windows needs
* atleast 1 socket in select().
*/
td->dummy_sock = socket(AF_INET, SOCK_DGRAM, 0);
return TRUE;
}
/*
* 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
*
* This is the version for resolves-in-a-thread.
*/
CURLcode Curl_wait_for_resolv(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
struct thread_data *td = (struct thread_data*) conn->async.os_specific;
struct SessionHandle *data = conn->data;
long timeout;
DWORD status, ticks;
CURLcode rc;
curlassert (conn && td);
/* now, see if there's a connect timeout or a regular timeout to
use instead of the default one */
timeout =
conn->data->set.connecttimeout ? conn->data->set.connecttimeout :
conn->data->set.timeout ? conn->data->set.timeout :
CURL_TIMEOUT_RESOLVE; /* default name resolve timeout */
ticks = GetTickCount();
/* wait for the thread to resolve the name */
status = WaitForSingleObject(td->event_resolved, 1000UL*timeout);
/* mark that we are now done waiting */
ReleaseMutex(td->mutex_waiting);
/* close our handle to the mutex, no point in hanging on to it */
CloseHandle(td->mutex_waiting);
td->mutex_waiting = NULL;
/* close the event handle, it's useless now */
CloseHandle(td->event_resolved);
td->event_resolved = NULL;
/* has the resolver thread succeeded in resolving our query ? */
if (status == WAIT_OBJECT_0) {
/* wait for the thread to exit, it's in the callback sequence */
if (WaitForSingleObject(td->thread_hnd, 5000) == WAIT_TIMEOUT) {
TerminateThread(td->thread_hnd, 0);
conn->async.done = TRUE;
td->thread_status = (DWORD)-1;
TRACE(("%s() thread stuck?!, ", THREAD_NAME));
}
else {
/* Thread finished before timeout; propagate Winsock error to this thread.
* 'conn->async.done = TRUE' is set in Curl_addrinfo4/6_callback().
*/
WSASetLastError(conn->async.status);
GetExitCodeThread(td->thread_hnd, &td->thread_status);
TRACE(("%s() status %lu, thread retval %lu, ",
THREAD_NAME, status, td->thread_status));
}
}
else {
conn->async.done = TRUE;
td->thread_status = (DWORD)-1;
TRACE(("%s() timeout, ", THREAD_NAME));
}
TRACE(("elapsed %lu ms\n", GetTickCount()-ticks));
CloseHandle(td->thread_hnd);
if(entry)
*entry = conn->async.dns;
rc = CURLE_OK;
if (!conn->async.dns) {
/* a name was not resolved */
if (td->thread_status == (DWORD)-1 || conn->async.status == NO_DATA) {
failf(data, "Resolving host timed out: %s", conn->host.name);
rc = CURLE_OPERATION_TIMEDOUT;
}
else if(conn->async.done) {
failf(data, "Could not resolve host: %s; %s",
conn->host.name, Curl_strerror(conn,conn->async.status));
rc = CURLE_COULDNT_RESOLVE_HOST;
}
else
rc = CURLE_OPERATION_TIMEDOUT;
}
destroy_thread_data(&conn->async);
if(CURLE_OK != rc)
/* close the connection, since we must not return failure from here
without cleaning up this connection properly */
Curl_disconnect(conn);
return (rc);
}
/*
* 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.
*/
CURLcode Curl_is_resolved(struct connectdata *conn,
struct Curl_dns_entry **entry)
{
*entry = NULL;
if (conn->async.done) {
/* we're done */
destroy_thread_data(&conn->async);
if (!conn->async.dns) {
TRACE(("Curl_is_resolved(): CURLE_COULDNT_RESOLVE_HOST\n"));
return CURLE_COULDNT_RESOLVE_HOST;
}
*entry = conn->async.dns;
TRACE(("resolved okay, dns %p\n", *entry));
}
else
TRACE(("not yet\n"));
return CURLE_OK;
}
CURLcode Curl_fdset(struct connectdata *conn,
fd_set *read_fd_set,
fd_set *write_fd_set,
int *max_fdp)
{
const struct thread_data *td =
(const struct thread_data *) conn->async.os_specific;
if (td && td->dummy_sock != CURL_SOCKET_BAD) {
FD_SET(td->dummy_sock,write_fd_set);
*max_fdp = td->dummy_sock;
}
(void) read_fd_set;
return CURLE_OK;
}
#ifdef CURLRES_IPV4
/*
* Curl_getaddrinfo() - for Windows threading without ENABLE_IPV6.
*/
Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
char *hostname,
int port,
int *waitp)
{
struct hostent *h = NULL;
struct SessionHandle *data = conn->data;
in_addr_t in;
*waitp = 0; /* don't wait, we act synchronously */
in = inet_addr(hostname);
if (in != CURL_INADDR_NONE)
/* This is a dotted IP address 123.123.123.123-style */
return Curl_ip2addr(in, hostname, port);
/* fire up a new resolver thread! */
if (init_resolve_thread(conn, hostname, port, NULL)) {
*waitp = TRUE; /* please wait for the response */
return NULL;
}
/* fall-back to blocking version */
infof(data, "init_resolve_thread() failed for %s; %s\n",
hostname, Curl_strerror(conn,GetLastError()));
h = gethostbyname(hostname);
if (!h) {
infof(data, "gethostbyname(2) failed for %s:%d; %s\n",
hostname, port, Curl_strerror(conn,WSAGetLastError()));
return NULL;
}
return Curl_he2ai(h, port);
}
#endif /* CURLRES_IPV4 */
#ifdef CURLRES_IPV6
/*
* Curl_getaddrinfo() - for Windows threading IPv6 enabled
*/
Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
char *hostname,
int port,
int *waitp)
{
struct addrinfo hints, *res;
int error;
char sbuf[NI_MAXSERV];
curl_socket_t s;
int pf;
struct SessionHandle *data = conn->data;
*waitp = FALSE; /* default to synch response */
/* see if we have an IPv6 stack */
s = socket(PF_INET6, SOCK_DGRAM, 0);
if (s == CURL_SOCKET_BAD) {
/* Some non-IPv6 stacks have been found to make very slow name resolves
* when PF_UNSPEC is used, so thus we switch to a mere PF_INET lookup if
* the stack seems to be a non-ipv6 one. */
pf = PF_INET;
}
else {
/* This seems to be an IPv6-capable stack, use PF_UNSPEC for the widest
* possible checks. And close the socket again.
*/
sclose(s);
/*
* Check if a more limited name resolve has been requested.
*/
switch(data->set.ip_version) {
case CURL_IPRESOLVE_V4:
pf = PF_INET;
break;
case CURL_IPRESOLVE_V6:
pf = PF_INET6;
break;
default:
pf = PF_UNSPEC;
break;
}
}
memset(&hints, 0, sizeof(hints));
hints.ai_family = pf;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_CANONNAME;
itoa(port, sbuf, 10);
/* fire up a new resolver thread! */
if (init_resolve_thread(conn, hostname, port, &hints)) {
*waitp = TRUE; /* please wait for the response */
return NULL;
}
/* fall-back to blocking version */
infof(data, "init_resolve_thread() failed for %s; %s\n",
hostname, Curl_strerror(conn,GetLastError()));
error = getaddrinfo(hostname, sbuf, &hints, &res);
if (error) {
infof(data, "getaddrinfo() failed for %s:%d; %s\n",
hostname, port, Curl_strerror(conn,WSAGetLastError()));
return NULL;
}
return res;
}
#endif /* CURLRES_IPV6 */
#endif /* CURLRES_THREADED */