/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2006, Daniel Stenberg, , 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: hostthre.c,v 1.42 2006-07-25 13:49:50 yangtse Exp $ ***************************************************************************/ #include "setup.h" #include #include #ifdef NEED_MALLOC_H #include #endif #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_NETDB_H #include #endif #ifdef HAVE_ARPA_INET_H #include #endif #ifdef HAVE_STDLIB_H #include /* required for free() prototypes */ #endif #ifdef HAVE_UNISTD_H #include /* for the close() proto */ #endif #ifdef VMS #include #include #include #endif #ifdef HAVE_SETJMP_H #include #endif #ifdef HAVE_PROCESS_H #include #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" #include "multiif.h" #define _MPRINTF_REPLACE /* use our functions only */ #include #include "inet_ntop.h" #include "memory.h" /* The last #include file should be: */ #include "memdebug.h" #if defined(_MSC_VER) && defined(CURL_NO__BEGINTHREADEX) #pragma message ("No _beginthreadex() available in this RTL") #endif /*********************************************************************** * 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 : ""); 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_resolv_fdset() */ HANDLE mutex_waiting; /* marks that we are still waiting for a resolve */ HANDLE event_resolved; /* marks that the thread obtained the information */ HANDLE event_thread_started; /* marks that the thread has initialized and started */ HANDLE mutex_terminate; /* serializes access to flag_terminate */ HANDLE event_terminate; /* flag for thread to terminate instead of calling callbacks */ #ifdef CURLRES_IPV6 struct addrinfo hints; #endif }; /* Data for synchronization between resolver thread and its parent */ struct thread_sync_data { HANDLE mutex_waiting; /* thread_data.mutex_waiting duplicate */ HANDLE mutex_terminate; /* thread_data.mutex_terminate duplicate */ HANDLE event_terminate; /* thread_data.event_terminate duplicate */ char * hostname; /* hostname to resolve, Curl_async.hostname duplicate */ }; /* Destroy resolver thread synchronization data */ static void destroy_thread_sync_data(struct thread_sync_data * tsd) { if (tsd->hostname) { free(tsd->hostname); tsd->hostname = NULL; } if (tsd->event_terminate) { CloseHandle(tsd->event_terminate); tsd->event_terminate = NULL; } if (tsd->mutex_terminate) { CloseHandle(tsd->mutex_terminate); tsd->mutex_terminate = NULL; } if (tsd->mutex_waiting) { CloseHandle(tsd->mutex_waiting); tsd->mutex_waiting = NULL; } } /* Initialize resolver thread synchronization data */ static BOOL init_thread_sync_data(struct thread_data * td, char * hostname, struct thread_sync_data * tsd) { HANDLE curr_proc = GetCurrentProcess(); memset(tsd, 0, sizeof(tsd)); if (!DuplicateHandle(curr_proc, td->mutex_waiting, curr_proc, &tsd->mutex_waiting, 0, FALSE, DUPLICATE_SAME_ACCESS)) { /* failed to duplicate the mutex, no point in continuing */ destroy_thread_sync_data(tsd); return FALSE; } if (!DuplicateHandle(curr_proc, td->mutex_terminate, curr_proc, &tsd->mutex_terminate, 0, FALSE, DUPLICATE_SAME_ACCESS)) { /* failed to duplicate the mutex, no point in continuing */ destroy_thread_sync_data(tsd); return FALSE; } if (!DuplicateHandle(curr_proc, td->event_terminate, curr_proc, &tsd->event_terminate, 0, FALSE, DUPLICATE_SAME_ACCESS)) { /* failed to duplicate the event, no point in continuing */ destroy_thread_sync_data(tsd); return FALSE; } /* Copying hostname string because original can be destroyed by parent * thread during gethostbyname execution. */ tsd->hostname = strdup(hostname); if (!tsd->hostname) { /* Memory allocation failed */ destroy_thread_sync_data(tsd); return FALSE; } return TRUE; } /* acquire resolver thread synchronization */ static BOOL acquire_thread_sync(struct thread_sync_data * tsd) { /* is the thread initiator still waiting for us ? */ if (WaitForSingleObject(tsd->mutex_waiting, 0) == WAIT_TIMEOUT) { /* yes, it is */ /* Waiting access to event_terminate */ if (WaitForSingleObject(tsd->mutex_terminate, INFINITE) != WAIT_OBJECT_0) { /* Something went wrong - now just ignoring */ } else { if (WaitForSingleObject(tsd->event_terminate, 0) != WAIT_TIMEOUT) { /* Parent thread signaled us to terminate. * This means that all data in conn->async is now destroyed * and we cannot use it. */ } else { return TRUE; } } } return FALSE; } /* release resolver thread synchronization */ static void release_thread_sync(struct thread_sync_data * tsd) { ReleaseMutex(tsd->mutex_terminate); } #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 and event handles. * This allows us to use it even after the container gets destroyed * due to a resolver timeout. */ struct thread_sync_data tsd = { 0,0,0,NULL }; if (!init_thread_sync_data(td, conn->async.hostname, &tsd)) { /* thread synchronization data initialization failed */ return (unsigned)-1; } WSASetLastError (conn->async.status = NO_DATA); /* pending status */ /* Signaling that we have initialized all copies of data and handles we need */ SetEvent(td->event_thread_started); he = gethostbyname (tsd.hostname); /* is parent thread waiting for us and are we able to access conn members? */ if (acquire_thread_sync(&tsd)) { /* Mark that we have obtained the information, and that we are calling * back with it. */ SetEvent(td->event_resolved); if (he) { rc = Curl_addrinfo4_callback(conn, CURL_ASYNC_SUCCESS, he); } else { rc = Curl_addrinfo4_callback(conn, (int)WSAGetLastError(), NULL); } TRACE(("Winsock-error %d, addr %s\n", conn->async.status, he ? inet_ntoa(*(struct in_addr*)he->h_addr) : "unknown")); release_thread_sync(&tsd); } /* clean up */ destroy_thread_sync_data(&tsd); 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; struct addrinfo hints = td->hints; /* Duplicate the passed mutex handle. * This allows us to use it even after the container gets destroyed * due to a resolver timeout. */ struct thread_sync_data tsd = { 0,0,0,NULL }; if (!init_thread_sync_data(td, conn->async.hostname, &tsd)) { /* thread synchronization data initialization failed */ return -1; } itoa(conn->async.port, service, 10); WSASetLastError(conn->async.status = NO_DATA); /* pending status */ /* Signaling that we have initialized all copies of data and handles we need */ SetEvent(td->event_thread_started); rc = getaddrinfo(tsd.hostname, service, &hints, &res); /* is parent thread waiting for us and are we able to access conn members? */ if (acquire_thread_sync(&tsd)) { /* 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 rc = Curl_addrinfo6_callback(conn, CURL_ASYNC_SUCCESS, res); } else { rc = Curl_addrinfo6_callback(conn, (int)WSAGetLastError(), NULL); TRACE(("Winsock-error %d, no address\n", conn->async.status)); } release_thread_sync(&tsd); } /* clean up */ destroy_thread_sync_data(&tsd); return (rc); /* An implicit _endthreadex() here */ } #endif /* * Curl_destroy_thread_data() cleans up async resolver data and thread handle. * Complementary of ares_destroy. */ void Curl_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 (td->mutex_terminate && td->event_terminate) { /* Signaling resolver thread to terminate */ if (WaitForSingleObject(td->mutex_terminate, INFINITE) == WAIT_OBJECT_0) { SetEvent(td->event_terminate); ReleaseMutex(td->mutex_terminate); } else { /* Something went wrong - just ignoring it */ } } if (td->mutex_terminate) CloseHandle(td->mutex_terminate); if (td->event_terminate) CloseHandle(td->event_terminate); if (td->event_thread_started) CloseHandle(td->event_thread_started); if (sock != CURL_SOCKET_BAD) sclose(sock); /* destroy the synchronization objects */ if (td->mutex_waiting) CloseHandle(td->mutex_waiting); td->mutex_waiting = NULL; if (td->event_resolved) CloseHandle(td->event_resolved); if (td->thread_hnd) CloseHandle(td->thread_hnd); 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); HANDLE thread_and_event[2] = {0}; 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) { Curl_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) { Curl_destroy_thread_data(&conn->async); SetLastError(EAGAIN); return FALSE; } /* Create the mutex used to serialize access to event_terminated * between us and resolver thread. */ td->mutex_terminate = CreateMutex(NULL, FALSE, NULL); if (td->mutex_terminate == NULL) { Curl_destroy_thread_data(&conn->async); SetLastError(EAGAIN); return FALSE; } /* Create the event used to signal thread that it should terminate. */ td->event_terminate = CreateEvent(NULL, TRUE, FALSE, NULL); if (td->event_terminate == NULL) { Curl_destroy_thread_data(&conn->async); SetLastError(EAGAIN); return FALSE; } /* Create the event used by thread to inform it has initialized its own data. */ td->event_thread_started = CreateEvent(NULL, TRUE, FALSE, NULL); if (td->event_thread_started == NULL) { Curl_destroy_thread_data(&conn->async); SetLastError(EAGAIN); return FALSE; } #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) { #ifdef _WIN32_WCE TRACE(("CreateThread() failed; %s\n", Curl_strerror(conn,GetLastError()))); #else SetLastError(errno); TRACE(("_beginthreadex() failed; %s\n", Curl_strerror(conn,errno))); #endif Curl_destroy_thread_data(&conn->async); return FALSE; } /* Waiting until the thread will initialize its data or it will exit due errors. */ thread_and_event[0] = td->thread_hnd; thread_and_event[1] = td->event_thread_started; if (WaitForMultipleObjects(sizeof(thread_and_event) / sizeof(thread_and_event[0]), (const HANDLE*)thread_and_event, FALSE, INFINITE) == WAIT_FAILED) { /* The resolver thread has been created, * most probably it works now - ignoring this "minor" error */ } /* This socket is only to keep Curl_resolv_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)); if(entry) *entry = conn->async.dns; rc = CURLE_OK; if (!conn->async.dns) { /* a name was not resolved */ if (td->thread_status == CURLE_OUT_OF_MEMORY) { rc = CURLE_OUT_OF_MEMORY; failf(data, "Could not resolve host: %s", curl_easy_strerror(rc)); } else if(conn->async.done) { if(conn->bits.httpproxy) { failf(data, "Could not resolve proxy: %s; %s", conn->proxy.dispname, Curl_strerror(conn, conn->async.status)); rc = CURLE_COULDNT_RESOLVE_PROXY; } else { failf(data, "Could not resolve host: %s; %s", conn->host.name, Curl_strerror(conn, conn->async.status)); rc = CURLE_COULDNT_RESOLVE_HOST; } } else 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 rc = CURLE_OPERATION_TIMEDOUT; } Curl_destroy_thread_data(&conn->async); if(!conn->async.dns) conn->bits.close = TRUE; 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 */ Curl_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)); } return CURLE_OK; } int Curl_resolv_getsock(struct connectdata *conn, curl_socket_t *socks, int numsocks) { const struct thread_data *td = (const struct thread_data *) conn->async.os_specific; if (td && td->dummy_sock != CURL_SOCKET_BAD) { if(numsocks) { /* return one socket waiting for writable, even though this is just a dummy */ socks[0] = td->dummy_sock; return GETSOCK_WRITESOCK(0); } } return 0; } #ifdef CURLRES_IPV4 /* * Curl_getaddrinfo() - for Windows threading without ENABLE_IPV6. */ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, const 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, const 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 = conn->socktype; #if 0 /* removed nov 8 2005 before 7.15.1 */ hints.ai_flags = AI_CANONNAME; #endif 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 */