src/httpfetch.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "socket.h" // for select()
  21 #include "porting.h" // for sleep_ms()
  22 #include "httpfetch.h"
  23 #include <iostream>
  24 #include <sstream>
  25 #include <list>
  26 #include <map>
  27 #include <errno.h>
  28 #ifndef _WIN32
  29 #include <sys/utsname.h>
  30 #endif
  31 #include "jthread/jevent.h"
  32 #include "config.h"
  33 #include "exceptions.h"
  34 #include "debug.h"
  35 #include "log.h"
  36 #include "util/container.h"
  37 #include "util/thread.h"
  38 #include "version.h"
  39 #include "main.h"
  40 #include "settings.h"
  41
  42 JMutex g_httpfetch_mutex;
  43 std::map<unsigned long, std::list<HTTPFetchResult> > g_httpfetch_results;
  44
  45 HTTPFetchRequest::HTTPFetchRequest()
  46 {
  47         url = "";
  48         caller = HTTPFETCH_DISCARD;
  49         request_id = 0;
  50         timeout = g_settings->getS32("curl_timeout");
  51         connect_timeout = timeout * 5;
  52
  53         useragent = std::string("Minetest/") + minetest_version_hash + " ";
  54 #ifdef _WIN32
  55         useragent += "(Windows)";
  56 #else
  57         struct utsname osinfo;
  58         uname(&osinfo);
  59         useragent += std::string("(") + osinfo.sysname + "/"
  60                         + osinfo.release + " " + osinfo.machine + ")";
  61 #endif
  62 }
  63
  64
  65 static void httpfetch_deliver_result(const HTTPFetchResult &fetchresult)
  66 {
  67         unsigned long caller = fetchresult.caller;
  68         if (caller != HTTPFETCH_DISCARD) {
  69                 JMutexAutoLock lock(g_httpfetch_mutex);
  70                 g_httpfetch_results[caller].push_back(fetchresult);
  71         }
  72 }
  73
  74 static void httpfetch_request_clear(unsigned long caller);
  75
  76 unsigned long httpfetch_caller_alloc()
  77 {
  78         JMutexAutoLock lock(g_httpfetch_mutex);
  79
  80         // Check each caller ID except HTTPFETCH_DISCARD
  81         const unsigned long discard = HTTPFETCH_DISCARD;
  82         for (unsigned long caller = discard + 1; caller != discard; ++caller) {
  83                 std::map<unsigned long, std::list<HTTPFetchResult> >::iterator
  84                         it = g_httpfetch_results.find(caller);
  85                 if (it == g_httpfetch_results.end()) {
  86                         verbosestream<<"httpfetch_caller_alloc: allocating "
  87                                         <<caller<<std::endl;
  88                         // Access element to create it
  89                         g_httpfetch_results[caller];
  90                         return caller;
  91                 }
  92         }
  93
  94         assert("httpfetch_caller_alloc: ran out of caller IDs" == 0);
  95         return discard;
  96 }
  97
  98 void httpfetch_caller_free(unsigned long caller)
  99 {
 100         verbosestream<<"httpfetch_caller_free: freeing "
 101                         <<caller<<std::endl;
 102
 103         httpfetch_request_clear(caller);
 104         if (caller != HTTPFETCH_DISCARD) {
 105                 JMutexAutoLock lock(g_httpfetch_mutex);
 106                 g_httpfetch_results.erase(caller);
 107         }
 108 }
 109
 110 bool httpfetch_async_get(unsigned long caller, HTTPFetchResult &fetchresult)
 111 {
 112         JMutexAutoLock lock(g_httpfetch_mutex);
 113
 114         // Check that caller exists
 115         std::map<unsigned long, std::list<HTTPFetchResult> >::iterator
 116                 it = g_httpfetch_results.find(caller);
 117         if (it == g_httpfetch_results.end())
 118                 return false;
 119
 120         // Check that result queue is nonempty
 121         std::list<HTTPFetchResult> &callerresults = it->second;
 122         if (callerresults.empty())
 123                 return false;
 124
 125         // Pop first result
 126         fetchresult = callerresults.front();
 127         callerresults.pop_front();
 128         return true;
 129 }
 130
 131 #if USE_CURL
 132 #include <curl/curl.h>
 133
 134 /*
 135         USE_CURL is on: use cURL based httpfetch implementation
 136 */
 137
 138 static size_t httpfetch_writefunction(
 139                 char *ptr, size_t size, size_t nmemb, void *userdata)
 140 {
 141         std::ostringstream *stream = (std::ostringstream*)userdata;
 142         size_t count = size * nmemb;
 143         stream->write(ptr, count);
 144         return count;
 145 }
 146
 147 static size_t httpfetch_discardfunction(
 148                 char *ptr, size_t size, size_t nmemb, void *userdata)
 149 {
 150         return size * nmemb;
 151 }
 152
 153 class CurlHandlePool
 154 {
 155         std::list<CURL*> handles;
 156
 157 public:
 158         CurlHandlePool() {}
 159         ~CurlHandlePool()
 160         {
 161                 for (std::list<CURL*>::iterator it = handles.begin();
 162                                 it != handles.end(); ++it) {
 163                         curl_easy_cleanup(*it);
 164                 }
 165         }
 166         CURL * alloc()
 167         {
 168                 CURL *curl;
 169                 if (handles.empty()) {
 170                         curl = curl_easy_init();
 171                         if (curl == NULL) {
 172                                 errorstream<<"curl_easy_init returned NULL"<<std::endl;
 173                         }
 174                 }
 175                 else {
 176                         curl = handles.front();
 177                         handles.pop_front();
 178                 }
 179                 return curl;
 180         }
 181         void free(CURL *handle)
 182         {
 183                 if (handle)
 184                         handles.push_back(handle);
 185         }
 186 };
 187
 188 struct HTTPFetchOngoing
 189 {
 190         CurlHandlePool *pool;
 191         CURL *curl;
 192         CURLM *multi;
 193         HTTPFetchRequest request;
 194         HTTPFetchResult result;
 195         std::ostringstream oss;
 196         char *post_fields;
 197         struct curl_slist *httpheader;
 198
 199         HTTPFetchOngoing(HTTPFetchRequest request_, CurlHandlePool *pool_):
 200                 pool(pool_),
 201                 curl(NULL),
 202                 multi(NULL),
 203                 request(request_),
 204                 result(request_),
 205                 oss(std::ios::binary),
 206                 httpheader(NULL)
 207         {
 208                 curl = pool->alloc();
 209                 if (curl != NULL) {
 210                         // Set static cURL options
 211                         curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
 212                         curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
 213                         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 214                         curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 1);
 215
 216 #if LIBCURL_VERSION_NUM >= 0x071304
 217                         // Restrict protocols so that curl vulnerabilities in
 218                         // other protocols don't affect us.
 219                         // These settings were introduced in curl 7.19.4.
 220                         long protocols =
 221                                 CURLPROTO_HTTP |
 222                                 CURLPROTO_HTTPS |
 223                                 CURLPROTO_FTP |
 224                                 CURLPROTO_FTPS;
 225                         curl_easy_setopt(curl, CURLOPT_PROTOCOLS, protocols);
 226                         curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, protocols);
 227 #endif
 228
 229                         // Set cURL options based on HTTPFetchRequest
 230                         curl_easy_setopt(curl, CURLOPT_URL,
 231                                         request.url.c_str());
 232                         curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS,
 233                                         request.timeout);
 234                         curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS,
 235                                         request.connect_timeout);
 236
 237                         if (request.useragent != "")
 238                                 curl_easy_setopt(curl, CURLOPT_USERAGENT, request.useragent.c_str());
 239
 240                         // Set up a write callback that writes to the
 241                         // ostringstream ongoing->oss, unless the data
 242                         // is to be discarded
 243                         if (request.caller == HTTPFETCH_DISCARD) {
 244                                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 245                                                 httpfetch_discardfunction);
 246                                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 247                         }
 248                         else {
 249                                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 250                                                 httpfetch_writefunction);
 251                                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &oss);
 252                         }
 253                         // Set POST (or GET) data
 254                         if (request.post_fields.empty()) {
 255                                 curl_easy_setopt(curl, CURLOPT_HTTPGET, 1);
 256                         }
 257                         else {
 258                                 curl_easy_setopt(curl, CURLOPT_POST, 1);
 259                                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 260                                                 request.post_fields.size());
 261                                 curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
 262                                                 request.post_fields.c_str());
 263                                 // request.post_fields must now *never* be
 264                                 // modified until CURLOPT_POSTFIELDS is cleared
 265                         }
 266                         // Set additional HTTP headers
 267                         for (size_t i = 0; i < request.extra_headers.size(); ++i) {
 268                                 httpheader = curl_slist_append(
 269                                         httpheader,
 270                                         request.extra_headers[i].c_str());
 271                         }
 272                         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, httpheader);
 273                 }
 274         }
 275
 276         CURLcode start(CURLM *multi_)
 277         {
 278                 if (curl == NULL)
 279                         return CURLE_FAILED_INIT;
 280
 281                 if (multi_) {
 282                         // Multi interface (async)
 283                         CURLMcode mres = curl_multi_add_handle(multi_, curl);
 284                         if (mres != CURLM_OK) {
 285                                 errorstream<<"curl_multi_add_handle"
 286                                         <<" returned error code "<<mres
 287                                         <<std::endl;
 288                                 return CURLE_FAILED_INIT;
 289                         }
 290                         multi = multi_; // store for curl_multi_remove_handle
 291                         return CURLE_OK;
 292                 }
 293                 else {
 294                         // Easy interface (sync)
 295                         return curl_easy_perform(curl);
 296                 }
 297         }
 298
 299         void complete(CURLcode res)
 300         {
 301                 result.succeeded = (res == CURLE_OK);
 302                 result.timeout = (res == CURLE_OPERATION_TIMEDOUT);
 303                 result.data = oss.str();
 304
 305                 // Get HTTP/FTP response code
 306                 result.response_code = 0;
 307                 if (curl != NULL) {
 308                         if (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE,
 309                                         &result.response_code) != CURLE_OK) {
 310                                 //we failed to get a return code make sure it is still 0
 311                                 result.response_code = 0;
 312                         }
 313                 }
 314
 315                 if (res != CURLE_OK) {
 316                         infostream<<request.url<<" not found ("
 317                                 <<curl_easy_strerror(res)<<")"
 318                                 <<" (response code "<<result.response_code<<")"
 319                                 <<std::endl;
 320                 }
 321         }
 322
 323         ~HTTPFetchOngoing()
 324         {
 325                 if (multi != NULL) {
 326                         CURLMcode mres = curl_multi_remove_handle(multi, curl);
 327                         if (mres != CURLM_OK) {
 328                                 errorstream<<"curl_multi_remove_handle"
 329                                         <<" returned error code "<<mres
 330                                         <<std::endl;
 331                         }
 332                 }
 333
 334                 // Set safe options for the reusable cURL handle
 335                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 336                                 httpfetch_discardfunction);
 337                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 338                 curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
 339                 if (httpheader != NULL) {
 340                         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, NULL);
 341                         curl_slist_free_all(httpheader);
 342                 }
 343
 344                 // Store the cURL handle for reuse
 345                 pool->free(curl);
 346         }
 347 };
 348
 349 class CurlFetchThread : public JThread
 350 {
 351 protected:
 352         enum RequestType {
 353                 RT_FETCH,
 354                 RT_CLEAR,
 355                 RT_WAKEUP,
 356         };
 357
 358         struct Request {
 359                 RequestType type;
 360                 HTTPFetchRequest fetchrequest;
 361                 Event *event;
 362         };
 363
 364         CURLM *m_multi;
 365         MutexedQueue<Request> m_requests;
 366         size_t m_parallel_limit;
 367
 368         // Variables exclusively used within thread
 369         std::vector<HTTPFetchOngoing*> m_all_ongoing;
 370         std::list<HTTPFetchRequest> m_queued_fetches;
 371
 372 public:
 373         CurlFetchThread(int parallel_limit)
 374         {
 375                 if (parallel_limit >= 1)
 376                         m_parallel_limit = parallel_limit;
 377                 else
 378                         m_parallel_limit = 1;
 379         }
 380
 381         void requestFetch(const HTTPFetchRequest &fetchrequest)
 382         {
 383                 Request req;
 384                 req.type = RT_FETCH;
 385                 req.fetchrequest = fetchrequest;
 386                 req.event = NULL;
 387                 m_requests.push_back(req);
 388         }
 389
 390         void requestClear(unsigned long caller, Event *event)
 391         {
 392                 Request req;
 393                 req.type = RT_CLEAR;
 394                 req.fetchrequest.caller = caller;
 395                 req.event = event;
 396                 m_requests.push_back(req);
 397         }
 398
 399         void requestWakeUp()
 400         {
 401                 Request req;
 402                 req.type = RT_WAKEUP;
 403                 req.event = NULL;
 404                 m_requests.push_back(req);
 405         }
 406
 407 protected:
 408         // Handle a request from some other thread
 409         // E.g. new fetch; clear fetches for one caller; wake up
 410         void processRequest(const Request &req)
 411         {
 412                 if (req.type == RT_FETCH) {
 413                         // New fetch, queue until there are less
 414                         // than m_parallel_limit ongoing fetches
 415                         m_queued_fetches.push_back(req.fetchrequest);
 416
 417                         // see processQueued() for what happens next
 418
 419                 }
 420                 else if (req.type == RT_CLEAR) {
 421                         unsigned long caller = req.fetchrequest.caller;
 422
 423                         // Abort all ongoing fetches for the caller
 424                         for (std::vector<HTTPFetchOngoing*>::iterator
 425                                         it = m_all_ongoing.begin();
 426                                         it != m_all_ongoing.end();) {
 427                                 if ((*it)->request.caller == caller) {
 428                                         delete (*it);
 429                                         it = m_all_ongoing.erase(it);
 430                                 }
 431                                 else
 432                                         ++it;
 433                         }
 434
 435                         // Also abort all queued fetches for the caller
 436                         for (std::list<HTTPFetchRequest>::iterator
 437                                         it = m_queued_fetches.begin();
 438                                         it != m_queued_fetches.end();) {
 439                                 if ((*it).caller == caller)
 440                                         it = m_queued_fetches.erase(it);
 441                                 else
 442                                         ++it;
 443                         }
 444                 }
 445                 else if (req.type == RT_WAKEUP) {
 446                         // Wakeup: Nothing to do, thread is awake at this point
 447                 }
 448
 449                 if (req.event != NULL)
 450                         req.event->signal();
 451         }
 452
 453         // Start new ongoing fetches if m_parallel_limit allows
 454         void processQueued(CurlHandlePool *pool)
 455         {
 456                 while (m_all_ongoing.size() < m_parallel_limit &&
 457                                 !m_queued_fetches.empty()) {
 458                         HTTPFetchRequest request = m_queued_fetches.front();
 459                         m_queued_fetches.pop_front();
 460
 461                         // Create ongoing fetch data and make a cURL handle
 462                         // Set cURL options based on HTTPFetchRequest
 463                         HTTPFetchOngoing *ongoing =
 464                                 new HTTPFetchOngoing(request, pool);
 465
 466                         // Initiate the connection (curl_multi_add_handle)
 467                         CURLcode res = ongoing->start(m_multi);
 468                         if (res == CURLE_OK) {
 469                                 m_all_ongoing.push_back(ongoing);
 470                         }
 471                         else {
 472                                 ongoing->complete(res);
 473                                 httpfetch_deliver_result(ongoing->result);
 474                                 delete ongoing;
 475                         }
 476                 }
 477         }
 478
 479         // Process CURLMsg (indicates completion of a fetch)
 480         void processCurlMessage(CURLMsg *msg)
 481         {
 482                 // Determine which ongoing fetch the message pertains to
 483                 size_t i = 0;
 484                 bool found = false;
 485                 for (i = 0; i < m_all_ongoing.size(); ++i) {
 486                         if (m_all_ongoing[i]->curl == msg->easy_handle) {
 487                                 found = true;
 488                                 break;
 489                         }
 490                 }
 491                 if (msg->msg == CURLMSG_DONE && found) {
 492                         // m_all_ongoing[i] succeeded or failed.
 493                         HTTPFetchOngoing *ongoing = m_all_ongoing[i];
 494                         ongoing->complete(msg->data.result);
 495                         httpfetch_deliver_result(ongoing->result);
 496                         delete ongoing;
 497                         m_all_ongoing.erase(m_all_ongoing.begin() + i);
 498                 }
 499         }
 500
 501         // Wait for a request from another thread, or timeout elapses
 502         void waitForRequest(long timeout)
 503         {
 504                 if (m_queued_fetches.empty()) {
 505                         try {
 506                                 Request req = m_requests.pop_front(timeout);
 507                                 processRequest(req);
 508                         }
 509                         catch (ItemNotFoundException &e) {}
 510                 }
 511         }
 512
 513         // Wait until some IO happens, or timeout elapses
 514         void waitForIO(long timeout)
 515         {
 516                 fd_set read_fd_set;
 517                 fd_set write_fd_set;
 518                 fd_set exc_fd_set;
 519                 int max_fd;
 520                 long select_timeout = -1;
 521                 struct timeval select_tv;
 522                 CURLMcode mres;
 523
 524                 FD_ZERO(&read_fd_set);
 525                 FD_ZERO(&write_fd_set);
 526                 FD_ZERO(&exc_fd_set);
 527
 528                 mres = curl_multi_fdset(m_multi, &read_fd_set,
 529                                 &write_fd_set, &exc_fd_set, &max_fd);
 530                 if (mres != CURLM_OK) {
 531                         errorstream<<"curl_multi_fdset"
 532                                 <<" returned error code "<<mres
 533                                 <<std::endl;
 534                         select_timeout = 0;
 535                 }
 536
 537                 mres = curl_multi_timeout(m_multi, &select_timeout);
 538                 if (mres != CURLM_OK) {
 539                         errorstream<<"curl_multi_timeout"
 540                                 <<" returned error code "<<mres
 541                                 <<std::endl;
 542                         select_timeout = 0;
 543                 }
 544
 545                 // Limit timeout so new requests get through
 546                 if (select_timeout < 0 || select_timeout > timeout)
 547                         select_timeout = timeout;
 548
 549                 if (select_timeout > 0) {
 550                         // in Winsock it is forbidden to pass three empty
 551                         // fd_sets to select(), so in that case use sleep_ms
 552                         if (max_fd != -1) {
 553                                 select_tv.tv_sec = select_timeout / 1000;
 554                                 select_tv.tv_usec = (select_timeout % 1000) * 1000;
 555                                 int retval = select(max_fd + 1, &read_fd_set,
 556                                                 &write_fd_set, &exc_fd_set,
 557                                                 &select_tv);
 558                                 if (retval == -1) {
 559                                         #ifdef _WIN32
 560                                         errorstream<<"select returned error code "
 561                                                 <<WSAGetLastError()<<std::endl;
 562                                         #else
 563                                         errorstream<<"select returned error code "
 564                                                 <<errno<<std::endl;
 565                                         #endif
 566                                 }
 567                         }
 568                         else {
 569                                 sleep_ms(select_timeout);
 570                         }
 571                 }
 572         }
 573
 574         void * Thread()
 575         {
 576                 ThreadStarted();
 577                 log_register_thread("CurlFetchThread");
 578                 DSTACK(__FUNCTION_NAME);
 579
 580                 CurlHandlePool pool;
 581
 582                 m_multi = curl_multi_init();
 583                 if (m_multi == NULL) {
 584                         errorstream<<"curl_multi_init returned NULL\n";
 585                         return NULL;
 586                 }
 587
 588                 assert(m_all_ongoing.empty());
 589
 590                 while (!StopRequested()) {
 591                         BEGIN_DEBUG_EXCEPTION_HANDLER
 592
 593                         /*
 594                                 Handle new async requests
 595                         */
 596
 597                         while (!m_requests.empty()) {
 598                                 Request req = m_requests.pop_frontNoEx();
 599                                 processRequest(req);
 600                         }
 601                         processQueued(&pool);
 602
 603                         /*
 604                                 Handle ongoing async requests
 605                         */
 606
 607                         int still_ongoing = 0;
 608                         while (curl_multi_perform(m_multi, &still_ongoing) ==
 609                                         CURLM_CALL_MULTI_PERFORM)
 610                                 /* noop */;
 611
 612                         /*
 613                                 Handle completed async requests
 614                         */
 615                         if (still_ongoing < (int) m_all_ongoing.size()) {
 616                                 CURLMsg *msg;
 617                                 int msgs_in_queue;
 618                                 msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 619                                 while (msg != NULL) {
 620                                         processCurlMessage(msg);
 621                                         msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 622                                 }
 623                         }
 624
 625                         /*
 626                                 If there are ongoing requests, wait for data
 627                                 (with a timeout of 100ms so that new requests
 628                                 can be processed).
 629
 630                                 If no ongoing requests, wait for a new request.
 631                                 (Possibly an empty request that signals
 632                                 that the thread should be stopped.)
 633                         */
 634                         if (m_all_ongoing.empty())
 635                                 waitForRequest(100000000);
 636                         else
 637                                 waitForIO(100);
 638
 639                         END_DEBUG_EXCEPTION_HANDLER(errorstream)
 640                 }
 641
 642                 // Call curl_multi_remove_handle and cleanup easy handles
 643                 for (size_t i = 0; i < m_all_ongoing.size(); ++i) {
 644                         delete m_all_ongoing[i];
 645                 }
 646                 m_all_ongoing.clear();
 647
 648                 m_queued_fetches.clear();
 649
 650                 CURLMcode mres = curl_multi_cleanup(m_multi);
 651                 if (mres != CURLM_OK) {
 652                         errorstream<<"curl_multi_cleanup"
 653                                 <<" returned error code "<<mres
 654                                 <<std::endl;
 655                 }
 656
 657                 return NULL;
 658         }
 659 };
 660
 661 CurlFetchThread *g_httpfetch_thread = NULL;
 662
 663 void httpfetch_init(int parallel_limit)
 664 {
 665         verbosestream<<"httpfetch_init: parallel_limit="<<parallel_limit
 666                         <<std::endl;
 667
 668         CURLcode res = curl_global_init(CURL_GLOBAL_DEFAULT);
 669         assert(res == CURLE_OK);
 670
 671         g_httpfetch_thread = new CurlFetchThread(parallel_limit);
 672 }
 673
 674 void httpfetch_cleanup()
 675 {
 676         verbosestream<<"httpfetch_cleanup: cleaning up"<<std::endl;
 677
 678         g_httpfetch_thread->Stop();
 679         g_httpfetch_thread->requestWakeUp();
 680         g_httpfetch_thread->Wait();
 681         delete g_httpfetch_thread;
 682
 683         curl_global_cleanup();
 684 }
 685
 686 void httpfetch_async(const HTTPFetchRequest &fetchrequest)
 687 {
 688         g_httpfetch_thread->requestFetch(fetchrequest);
 689         if (!g_httpfetch_thread->IsRunning())
 690                 g_httpfetch_thread->Start();
 691 }
 692
 693 static void httpfetch_request_clear(unsigned long caller)
 694 {
 695         if (g_httpfetch_thread->IsRunning()) {
 696                 Event event;
 697                 g_httpfetch_thread->requestClear(caller, &event);
 698                 event.wait();
 699         }
 700         else {
 701                 g_httpfetch_thread->requestClear(caller, NULL);
 702         }
 703 }
 704
 705 void httpfetch_sync(const HTTPFetchRequest &fetchrequest,
 706                 HTTPFetchResult &fetchresult)
 707 {
 708         // Create ongoing fetch data and make a cURL handle
 709         // Set cURL options based on HTTPFetchRequest
 710         CurlHandlePool pool;
 711         HTTPFetchOngoing ongoing(fetchrequest, &pool);
 712         // Do the fetch (curl_easy_perform)
 713         CURLcode res = ongoing.start(NULL);
 714         // Update fetchresult
 715         ongoing.complete(res);
 716         fetchresult = ongoing.result;
 717 }
 718
 719 #else  // USE_CURL
 720
 721 /*
 722         USE_CURL is off:
 723
 724         Dummy httpfetch implementation that always returns an error.
 725 */
 726
 727 void httpfetch_init(int parallel_limit)
 728 {
 729 }
 730
 731 void httpfetch_cleanup()
 732 {
 733 }
 734
 735 void httpfetch_async(const HTTPFetchRequest &fetchrequest)
 736 {
 737         errorstream<<"httpfetch_async: unable to fetch "<<fetchrequest.url
 738                         <<" because USE_CURL=0"<<std::endl;
 739
 740         HTTPFetchResult fetchresult(fetchrequest); // sets succeeded = false etc.
 741         httpfetch_deliver_result(fetchresult);
 742 }
 743
 744 static void httpfetch_request_clear(unsigned long caller)
 745 {
 746 }
 747
 748 void httpfetch_sync(const HTTPFetchRequest &fetchrequest,
 749                 HTTPFetchResult &fetchresult)
 750 {
 751         errorstream<<"httpfetch_sync: unable to fetch "<<fetchrequest.url
 752                         <<" because USE_CURL=0"<<std::endl;
 753
 754         fetchresult = HTTPFetchResult(fetchrequest); // sets succeeded = false etc.
 755 }
 756
 757 #endif  // USE_CURL