diff options
Diffstat (limited to 'lib/asyn-thread.c')
-rw-r--r-- | lib/asyn-thread.c | 679 |
1 files changed, 679 insertions, 0 deletions
diff --git a/lib/asyn-thread.c b/lib/asyn-thread.c new file mode 100644 index 000000000..0d29d5887 --- /dev/null +++ b/lib/asyn-thread.c @@ -0,0 +1,679 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2012, 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. + * + ***************************************************************************/ + +#include "setup.h" + +#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 __VMS +#include <in.h> +#include <inet.h> +#endif + +#if defined(USE_THREADS_POSIX) +# ifdef HAVE_PTHREAD_H +# include <pthread.h> +# endif +#elif defined(USE_THREADS_WIN32) +# ifdef HAVE_PROCESS_H +# include <process.h> +# endif +#endif + +#if (defined(NETWARE) && defined(__NOVELL_LIBC__)) +#undef in_addr_t +#define in_addr_t unsigned long +#endif + +#ifdef HAVE_GETADDRINFO +# define RESOLVER_ENOMEM EAI_MEMORY +#else +# define RESOLVER_ENOMEM ENOMEM +#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" +#include "inet_pton.h" +#include "inet_ntop.h" +#include "curl_threads.h" + +#define _MPRINTF_REPLACE /* use our functions only */ +#include <curl/mprintf.h> + +#include "curl_memory.h" +/* The last #include file should be: */ +#include "memdebug.h" + +/*********************************************************************** + * Only for threaded name resolves builds + **********************************************************************/ +#ifdef CURLRES_THREADED + +/* + * Curl_resolver_global_init() + * Called from curl_global_init() to initialize global resolver environment. + * Does nothing here. + */ +int Curl_resolver_global_init(void) +{ + return CURLE_OK; +} + +/* + * Curl_resolver_global_cleanup() + * Called from curl_global_cleanup() to destroy global resolver environment. + * Does nothing here. + */ +void Curl_resolver_global_cleanup(void) +{ +} + +/* + * Curl_resolver_init() + * Called from curl_easy_init() -> Curl_open() to initialize resolver + * URL-state specific environment ('resolver' member of the UrlState + * structure). Does nothing here. + */ +CURLcode Curl_resolver_init(void **resolver) +{ + (void)resolver; + return CURLE_OK; +} + +/* + * Curl_resolver_cleanup() + * Called from curl_easy_cleanup() -> Curl_close() to cleanup resolver + * URL-state specific environment ('resolver' member of the UrlState + * structure). Does nothing here. + */ +void Curl_resolver_cleanup(void *resolver) +{ + (void)resolver; +} + +/* + * Curl_resolver_duphandle() + * Called from curl_easy_duphandle() to duplicate resolver URL state-specific + * environment ('resolver' member of the UrlState structure). Does nothing + * here. + */ +int Curl_resolver_duphandle(void **to, void *from) +{ + (void)to; + (void)from; + return CURLE_OK; +} + +static void destroy_async_data(struct Curl_async *); + +/* + * Cancel all possibly still on-going resolves for this connection. + */ +void Curl_resolver_cancel(struct connectdata *conn) +{ + destroy_async_data(&conn->async); +} + +/* This function is used to init a threaded resolve */ +static bool init_resolve_thread(struct connectdata *conn, + const char *hostname, int port, + const struct addrinfo *hints); + + +/* Data for synchronization between resolver thread and its parent */ +struct thread_sync_data { + curl_mutex_t * mtx; + int done; + + char * hostname; /* hostname to resolve, Curl_async.hostname + duplicate */ + int port; + int sock_error; + Curl_addrinfo *res; +#ifdef HAVE_GETADDRINFO + struct addrinfo hints; +#endif +}; + +struct thread_data { + curl_thread_t thread_hnd; + unsigned int poll_interval; + int interval_end; + struct thread_sync_data tsd; +}; + +static struct thread_sync_data *conn_thread_sync_data(struct connectdata *conn) +{ + return &(((struct thread_data *)conn->async.os_specific)->tsd); +} + +#define CONN_THREAD_SYNC_DATA(conn) &(((conn)->async.os_specific)->tsd); + +/* Destroy resolver thread synchronization data */ +static +void destroy_thread_sync_data(struct thread_sync_data * tsd) +{ + if(tsd->mtx) { + Curl_mutex_destroy(tsd->mtx); + free(tsd->mtx); + } + + if(tsd->hostname) + free(tsd->hostname); + + if(tsd->res) + Curl_freeaddrinfo(tsd->res); + + memset(tsd,0,sizeof(*tsd)); +} + +/* Initialize resolver thread synchronization data */ +static +int init_thread_sync_data(struct thread_sync_data * tsd, + const char * hostname, + int port, + const struct addrinfo *hints) +{ + memset(tsd, 0, sizeof(*tsd)); + + tsd->port = port; +#ifdef CURLRES_IPV6 + DEBUGASSERT(hints); + tsd->hints = *hints; +#else + (void) hints; +#endif + + tsd->mtx = malloc(sizeof(curl_mutex_t)); + if(tsd->mtx == NULL) + goto err_exit; + + Curl_mutex_init(tsd->mtx); + + tsd->sock_error = CURL_ASYNC_SUCCESS; + + /* Copying hostname string because original can be destroyed by parent + * thread during gethostbyname execution. + */ + tsd->hostname = strdup(hostname); + if(!tsd->hostname) + goto err_exit; + + return 1; + + err_exit: + /* Memory allocation failed */ + destroy_thread_sync_data(tsd); + return 0; +} + +static int getaddrinfo_complete(struct connectdata *conn) +{ + struct thread_sync_data *tsd = conn_thread_sync_data(conn); + int rc; + + rc = Curl_addrinfo_callback(conn, tsd->sock_error, tsd->res); + /* The tsd->res structure has been copied to async.dns and perhaps the DNS + cache. Set our copy to NULL so destroy_thread_sync_data doesn't free it. + */ + tsd->res = NULL; + + return rc; +} + + +#ifdef HAVE_GETADDRINFO + +/* + * getaddrinfo_thread() resolves a name and then exits. + * + * For builds without ARES, but with ENABLE_IPV6, create a resolver thread + * and wait on it. + */ +static unsigned int CURL_STDCALL getaddrinfo_thread (void *arg) +{ + struct thread_sync_data *tsd = (struct thread_sync_data*)arg; + char service [NI_MAXSERV]; + int rc; + + snprintf(service, sizeof(service), "%d", tsd->port); + + rc = Curl_getaddrinfo_ex(tsd->hostname, service, &tsd->hints, &tsd->res); + + if(rc != 0) { + tsd->sock_error = SOCKERRNO?SOCKERRNO:rc; + if(tsd->sock_error == 0) + tsd->sock_error = RESOLVER_ENOMEM; + } + + Curl_mutex_acquire(tsd->mtx); + tsd->done = 1; + Curl_mutex_release(tsd->mtx); + + return 0; +} + +#else /* HAVE_GETADDRINFO */ + +/* + * gethostbyname_thread() resolves a name and then exits. + */ +static unsigned int CURL_STDCALL gethostbyname_thread (void *arg) +{ + struct thread_sync_data *tsd = (struct thread_sync_data *)arg; + + tsd->res = Curl_ipv4_resolve_r(tsd->hostname, tsd->port); + + if(!tsd->res) { + tsd->sock_error = SOCKERRNO; + if(tsd->sock_error == 0) + tsd->sock_error = RESOLVER_ENOMEM; + } + + Curl_mutex_acquire(tsd->mtx); + tsd->done = 1; + Curl_mutex_release(tsd->mtx); + + return 0; +} + +#endif /* HAVE_GETADDRINFO */ + +/* + * destroy_async_data() cleans up async resolver data and thread handle. + */ +static void destroy_async_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; + + if(td->thread_hnd != curl_thread_t_null) + Curl_thread_join(&td->thread_hnd); + + destroy_thread_sync_data(&td->tsd); + + 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 struct addrinfo *hints) +{ + struct thread_data *td = calloc(1, sizeof(struct thread_data)); + int err = RESOLVER_ENOMEM; + + conn->async.os_specific = (void*) td; + if(!td) + goto err_exit; + + conn->async.port = port; + conn->async.done = FALSE; + conn->async.status = 0; + conn->async.dns = NULL; + td->thread_hnd = curl_thread_t_null; + + if(!init_thread_sync_data(&td->tsd, hostname, port, hints)) + goto err_exit; + + Curl_safefree(conn->async.hostname); + conn->async.hostname = strdup(hostname); + if(!conn->async.hostname) + goto err_exit; + +#ifdef HAVE_GETADDRINFO + td->thread_hnd = Curl_thread_create(getaddrinfo_thread, &td->tsd); +#else + td->thread_hnd = Curl_thread_create(gethostbyname_thread, &td->tsd); +#endif + + if(!td->thread_hnd) { +#ifndef _WIN32_WCE + err = errno; +#endif + goto err_exit; + } + + return TRUE; + + err_exit: + destroy_async_data(&conn->async); + + SET_ERRNO(err); + + return FALSE; +} + +#if defined(HAVE_GETADDRINFO) && !defined(HAVE_GAI_STRERROR) && !defined(WIN32) +/* NetWare has getaddrinfo but lacks gai_strerror. + Windows has a gai_strerror but it is bad (not thread-safe) and the generic + socket error string function can be used for this pupose. */ +static const char *gai_strerror(int ecode) +{ + switch (ecode) { + case EAI_AGAIN: + return "The name could not be resolved at this time"; + case EAI_BADFLAGS: + return "The flags parameter had an invalid value"; + case EAI_FAIL: + return "A non-recoverable error occurred when attempting to " + "resolve the name"; + case EAI_FAMILY: + return "The address family was not recognized"; + case EAI_MEMORY: + return "Out of memory"; + case EAI_NONAME: + return "The name does not resolve for the supplied parameters"; + case EAI_SERVICE: + return "The service passed was not recognized for the " + "specified socket type" + case EAI_SOCKTYPE: + return "The intended socket type was not recognized" + case EAI_SYSTEM: + return "A system error occurred"; + case EAI_OVERFLOW: + return "An argument buffer overflowed"; + default: + return "Unknown error"; + +/* define this now as this is a private implementation of said function */ +#define HAVE_GAI_STRERROR +} +#endif + + +/* + * resolver_error() calls failf() with the appropriate message after a resolve + * error + */ + +static void resolver_error(struct connectdata *conn, const char *host_or_proxy) +{ + failf(conn->data, "Could not resolve %s: %s; %s", host_or_proxy, + conn->async.hostname, +#ifdef HAVE_GAI_STRERROR + /* NetWare doesn't have gai_strerror and on Windows it isn't deemed + thread-safe */ + gai_strerror(conn->async.status) +#else + Curl_strerror(conn, conn->async.status) +#endif + ); +} + +/* + * Curl_resolver_wait_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_resolver_wait_resolv(struct connectdata *conn, + struct Curl_dns_entry **entry) +{ + struct thread_data *td = (struct thread_data*) conn->async.os_specific; + CURLcode rc = CURLE_OK; + + DEBUGASSERT(conn && td); + + /* wait for the thread to resolve the name */ + if(Curl_thread_join(&td->thread_hnd)) + rc = getaddrinfo_complete(conn); + else + DEBUGASSERT(0); + + conn->async.done = TRUE; + + if(entry) + *entry = conn->async.dns; + + if(!conn->async.dns) { + /* a name was not resolved */ + if(conn->bits.httpproxy) { + resolver_error(conn, "proxy"); + rc = CURLE_COULDNT_RESOLVE_PROXY; + } + else { + resolver_error(conn, "host"); + rc = CURLE_COULDNT_RESOLVE_HOST; + } + } + + destroy_async_data(&conn->async); + + if(!conn->async.dns) + conn->bits.close = TRUE; + + return (rc); +} + +/* + * Curl_resolver_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_resolver_is_resolved(struct connectdata *conn, + struct Curl_dns_entry **entry) +{ + struct SessionHandle *data = conn->data; + struct thread_data *td = (struct thread_data*) conn->async.os_specific; + int done = 0; + + *entry = NULL; + + if(!td) { + DEBUGASSERT(td); + return CURLE_COULDNT_RESOLVE_HOST; + } + + Curl_mutex_acquire(td->tsd.mtx); + done = td->tsd.done; + Curl_mutex_release(td->tsd.mtx); + + if(done) { + getaddrinfo_complete(conn); + destroy_async_data(&conn->async); + + if(!conn->async.dns) { + resolver_error(conn, "host"); + return CURLE_COULDNT_RESOLVE_HOST; + } + *entry = conn->async.dns; + } + else { + /* poll for name lookup done with exponential backoff up to 250ms */ + int elapsed = Curl_tvdiff(Curl_tvnow(), data->progress.t_startsingle); + if(elapsed < 0) + elapsed = 0; + + if(td->poll_interval == 0) + /* Start at 1ms poll interval */ + td->poll_interval = 1; + else if(elapsed >= td->interval_end) + /* Back-off exponentially if last interval expired */ + td->poll_interval *= 2; + + if(td->poll_interval > 250) + td->poll_interval = 250; + + td->interval_end = elapsed + td->poll_interval; + Curl_expire(conn->data, td->poll_interval); + } + + return CURLE_OK; +} + +int Curl_resolver_getsock(struct connectdata *conn, + curl_socket_t *socks, + int numsocks) +{ + (void)conn; + (void)socks; + (void)numsocks; + return 0; +} + +#ifndef HAVE_GETADDRINFO +/* + * Curl_getaddrinfo() - for platforms without getaddrinfo + */ +Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, + const char *hostname, + int port, + int *waitp) +{ + struct in_addr in; + + *waitp = 0; /* default to synchronous response */ + + if(Curl_inet_pton(AF_INET, hostname, &in) > 0) + /* This is a dotted IP address 123.123.123.123-style */ + return Curl_ip2addr(AF_INET, &in, hostname, port); + + /* fire up a new resolver thread! */ + if(init_resolve_thread(conn, hostname, port, NULL)) { + *waitp = 1; /* expect asynchronous response */ + return NULL; + } + + /* fall-back to blocking version */ + return Curl_ipv4_resolve_r(hostname, port); +} + +#else /* !HAVE_GETADDRINFO */ + +/* + * Curl_resolver_getaddrinfo() - for getaddrinfo + */ +Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, + const char *hostname, + int port, + int *waitp) +{ + struct addrinfo hints; + struct in_addr in; + Curl_addrinfo *res; + int error; + char sbuf[NI_MAXSERV]; + int pf = PF_INET; +#ifdef CURLRES_IPV6 + struct in6_addr in6; +#endif /* CURLRES_IPV6 */ + + *waitp = 0; /* default to synchronous response */ + + /* First check if this is an IPv4 address string */ + if(Curl_inet_pton(AF_INET, hostname, &in) > 0) + /* This is a dotted IP address 123.123.123.123-style */ + return Curl_ip2addr(AF_INET, &in, hostname, port); + +#ifdef CURLRES_IPV6 + /* check if this is an IPv6 address string */ + if(Curl_inet_pton (AF_INET6, hostname, &in6) > 0) + /* This is an IPv6 address literal */ + return Curl_ip2addr(AF_INET6, &in6, hostname, port); + + /* + * Check if a limited name resolve has been requested. + */ + switch(conn->ip_version) { + case CURL_IPRESOLVE_V4: + pf = PF_INET; + break; + case CURL_IPRESOLVE_V6: + pf = PF_INET6; + break; + default: + pf = PF_UNSPEC; + break; + } + + if((pf != PF_INET) && !Curl_ipv6works()) + /* the stack seems to be a non-ipv6 one */ + pf = PF_INET; + +#endif /* CURLRES_IPV6 */ + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = pf; + hints.ai_socktype = conn->socktype; + + snprintf(sbuf, sizeof(sbuf), "%d", port); + + /* fire up a new resolver thread! */ + if(init_resolve_thread(conn, hostname, port, &hints)) { + *waitp = 1; /* expect asynchronous response */ + return NULL; + } + + /* fall-back to blocking version */ + infof(conn->data, "init_resolve_thread() failed for %s; %s\n", + hostname, Curl_strerror(conn, ERRNO)); + + error = Curl_getaddrinfo_ex(hostname, sbuf, &hints, &res); + if(error) { + infof(conn->data, "getaddrinfo() failed for %s:%d; %s\n", + hostname, port, Curl_strerror(conn, SOCKERRNO)); + return NULL; + } + return res; +} + +#endif /* !HAVE_GETADDRINFO */ + +CURLcode Curl_set_dns_servers(struct SessionHandle *data, + char *servers) +{ + (void)data; + (void)servers; + return CURLE_NOT_BUILT_IN; + +} + +#endif /* CURLRES_THREADED */ |