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(), get_sysinfo(), secure_rand_fill_buf()
  22 #include "httpfetch.h"
  23 #include <iostream>
  24 #include <sstream>
  25 #include <list>
  26 #include <map>
  27 #include <errno.h>
  28 #include "threading/event.h"
  29 #include "config.h"
  30 #include "exceptions.h"
  31 #include "debug.h"
  32 #include "log.h"
  33 #include "util/container.h"
  34 #include "util/thread.h"
  35 #include "version.h"
  36 #include "settings.h"
  37 #include "noise.h"
  38
  39 Mutex g_httpfetch_mutex;
  40 std::map<unsigned long, std::queue<HTTPFetchResult> > g_httpfetch_results;
  41 PcgRandom g_callerid_randomness;
  42
  43 HTTPFetchRequest::HTTPFetchRequest() :
  44         url(""),
  45         caller(HTTPFETCH_DISCARD),
  46         request_id(0),
  47         timeout(g_settings->getS32("curl_timeout")),
  48         connect_timeout(timeout),
  49         multipart(false),
  50         useragent(std::string(PROJECT_NAME_C "/") + g_version_hash + " (" + porting::get_sysinfo() + ")")
  51 {
  52 }
  53
  54
  55 static void httpfetch_deliver_result(const HTTPFetchResult &fetch_result)
  56 {
  57         unsigned long caller = fetch_result.caller;
  58         if (caller != HTTPFETCH_DISCARD) {
  59                 MutexAutoLock lock(g_httpfetch_mutex);
  60                 g_httpfetch_results[caller].push(fetch_result);
  61         }
  62 }
  63
  64 static void httpfetch_request_clear(unsigned long caller);
  65
  66 unsigned long httpfetch_caller_alloc()
  67 {
  68         MutexAutoLock lock(g_httpfetch_mutex);
  69
  70         // Check each caller ID except HTTPFETCH_DISCARD
  71         const unsigned long discard = HTTPFETCH_DISCARD;
  72         for (unsigned long caller = discard + 1; caller != discard; ++caller) {
  73                 std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
  74                         it = g_httpfetch_results.find(caller);
  75                 if (it == g_httpfetch_results.end()) {
  76                         verbosestream << "httpfetch_caller_alloc: allocating "
  77                                         << caller << std::endl;
  78                         // Access element to create it
  79                         g_httpfetch_results[caller];
  80                         return caller;
  81                 }
  82         }
  83
  84         FATAL_ERROR("httpfetch_caller_alloc: ran out of caller IDs");
  85         return discard;
  86 }
  87
  88 unsigned long httpfetch_caller_alloc_secure()
  89 {
  90         MutexAutoLock lock(g_httpfetch_mutex);
  91
  92         // Generate random caller IDs and make sure they're not
  93         // already used or equal to HTTPFETCH_DISCARD
  94         // Give up after 100 tries to prevent infinite loop
  95         u8 tries = 100;
  96         unsigned long caller;
  97
  98         do {
  99                 caller = (((u64) g_callerid_randomness.next()) << 32) |
 100                                 g_callerid_randomness.next();
 101
 102                 if (--tries < 1) {
 103                         FATAL_ERROR("httpfetch_caller_alloc_secure: ran out of caller IDs");
 104                         return HTTPFETCH_DISCARD;
 105                 }
 106         } while (g_httpfetch_results.find(caller) != g_httpfetch_results.end());
 107
 108         verbosestream << "httpfetch_caller_alloc_secure: allocating "
 109                 << caller << std::endl;
 110
 111         // Access element to create it
 112         g_httpfetch_results[caller];
 113         return caller;
 114 }
 115
 116 void httpfetch_caller_free(unsigned long caller)
 117 {
 118         verbosestream<<"httpfetch_caller_free: freeing "
 119                         <<caller<<std::endl;
 120
 121         httpfetch_request_clear(caller);
 122         if (caller != HTTPFETCH_DISCARD) {
 123                 MutexAutoLock lock(g_httpfetch_mutex);
 124                 g_httpfetch_results.erase(caller);
 125         }
 126 }
 127
 128 bool httpfetch_async_get(unsigned long caller, HTTPFetchResult &fetch_result)
 129 {
 130         MutexAutoLock lock(g_httpfetch_mutex);
 131
 132         // Check that caller exists
 133         std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
 134                 it = g_httpfetch_results.find(caller);
 135         if (it == g_httpfetch_results.end())
 136                 return false;
 137
 138         // Check that result queue is nonempty
 139         std::queue<HTTPFetchResult> &caller_results = it->second;
 140         if (caller_results.empty())
 141                 return false;
 142
 143         // Pop first result
 144         fetch_result = caller_results.front();
 145         caller_results.pop();
 146         return true;
 147 }
 148
 149 #if USE_CURL
 150 #include <curl/curl.h>
 151
 152 /*
 153         USE_CURL is on: use cURL based httpfetch implementation
 154 */
 155
 156 static size_t httpfetch_writefunction(
 157                 char *ptr, size_t size, size_t nmemb, void *userdata)
 158 {
 159         std::ostringstream *stream = (std::ostringstream*)userdata;
 160         size_t count = size * nmemb;
 161         stream->write(ptr, count);
 162         return count;
 163 }
 164
 165 static size_t httpfetch_discardfunction(
 166                 char *ptr, size_t size, size_t nmemb, void *userdata)
 167 {
 168         return size * nmemb;
 169 }
 170
 171 class CurlHandlePool
 172 {
 173         std::list<CURL*> handles;
 174
 175 public:
 176         CurlHandlePool() {}
 177         ~CurlHandlePool()
 178         {
 179                 for (std::list<CURL*>::iterator it = handles.begin();
 180                                 it != handles.end(); ++it) {
 181                         curl_easy_cleanup(*it);
 182                 }
 183         }
 184         CURL * alloc()
 185         {
 186                 CURL *curl;
 187                 if (handles.empty()) {
 188                         curl = curl_easy_init();
 189                         if (curl == NULL) {
 190                                 errorstream<<"curl_easy_init returned NULL"<<std::endl;
 191                         }
 192                 }
 193                 else {
 194                         curl = handles.front();
 195                         handles.pop_front();
 196                 }
 197                 return curl;
 198         }
 199         void free(CURL *handle)
 200         {
 201                 if (handle)
 202                         handles.push_back(handle);
 203         }
 204 };
 205
 206 class HTTPFetchOngoing
 207 {
 208 public:
 209         HTTPFetchOngoing(const HTTPFetchRequest &request, CurlHandlePool *pool);
 210         ~HTTPFetchOngoing();
 211
 212         CURLcode start(CURLM *multi);
 213         const HTTPFetchResult * complete(CURLcode res);
 214
 215         const HTTPFetchRequest &getRequest()    const { return request; };
 216         const CURL             *getEasyHandle() const { return curl; };
 217
 218 private:
 219         CurlHandlePool *pool;
 220         CURL *curl;
 221         CURLM *multi;
 222         HTTPFetchRequest request;
 223         HTTPFetchResult result;
 224         std::ostringstream oss;
 225         struct curl_slist *http_header;
 226         curl_httppost *post;
 227 };
 228
 229
 230 HTTPFetchOngoing::HTTPFetchOngoing(const HTTPFetchRequest &request_,
 231                 CurlHandlePool *pool_):
 232         pool(pool_),
 233         curl(NULL),
 234         multi(NULL),
 235         request(request_),
 236         result(request_),
 237         oss(std::ios::binary),
 238         http_header(NULL),
 239         post(NULL)
 240 {
 241         curl = pool->alloc();
 242         if (curl == NULL) {
 243                 return;
 244         }
 245
 246         // Set static cURL options
 247         curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
 248         curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
 249         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 250         curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 1);
 251
 252         std::string bind_address = g_settings->get("bind_address");
 253         if (!bind_address.empty()) {
 254                 curl_easy_setopt(curl, CURLOPT_INTERFACE, bind_address.c_str());
 255         }
 256
 257 #if LIBCURL_VERSION_NUM >= 0x071304
 258         // Restrict protocols so that curl vulnerabilities in
 259         // other protocols don't affect us.
 260         // These settings were introduced in curl 7.19.4.
 261         long protocols =
 262                 CURLPROTO_HTTP |
 263                 CURLPROTO_HTTPS |
 264                 CURLPROTO_FTP |
 265                 CURLPROTO_FTPS;
 266         curl_easy_setopt(curl, CURLOPT_PROTOCOLS, protocols);
 267         curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, protocols);
 268 #endif
 269
 270         // Set cURL options based on HTTPFetchRequest
 271         curl_easy_setopt(curl, CURLOPT_URL,
 272                         request.url.c_str());
 273         curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS,
 274                         request.timeout);
 275         curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS,
 276                         request.connect_timeout);
 277
 278         if (request.useragent != "")
 279                 curl_easy_setopt(curl, CURLOPT_USERAGENT, request.useragent.c_str());
 280
 281         // Set up a write callback that writes to the
 282         // ostringstream ongoing->oss, unless the data
 283         // is to be discarded
 284         if (request.caller == HTTPFETCH_DISCARD) {
 285                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 286                                 httpfetch_discardfunction);
 287                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 288         } else {
 289                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 290                                 httpfetch_writefunction);
 291                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &oss);
 292         }
 293
 294         // Set POST (or GET) data
 295         if (request.post_fields.empty() && request.post_data.empty()) {
 296                 curl_easy_setopt(curl, CURLOPT_HTTPGET, 1);
 297         } else if (request.multipart) {
 298                 curl_httppost *last = NULL;
 299                 for (StringMap::iterator it = request.post_fields.begin();
 300                                 it != request.post_fields.end(); ++it) {
 301                         curl_formadd(&post, &last,
 302                                         CURLFORM_NAMELENGTH, it->first.size(),
 303                                         CURLFORM_PTRNAME, it->first.c_str(),
 304                                         CURLFORM_CONTENTSLENGTH, it->second.size(),
 305                                         CURLFORM_PTRCONTENTS, it->second.c_str(),
 306                                         CURLFORM_END);
 307                 }
 308                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);
 309                 // request.post_fields must now *never* be
 310                 // modified until CURLOPT_HTTPPOST is cleared
 311         } else if (request.post_data.empty()) {
 312                 curl_easy_setopt(curl, CURLOPT_POST, 1);
 313                 std::string str;
 314                 for (StringMap::iterator it = request.post_fields.begin();
 315                                 it != request.post_fields.end(); ++it) {
 316                         if (str != "")
 317                                 str += "&";
 318                         str += urlencode(it->first);
 319                         str += "=";
 320                         str += urlencode(it->second);
 321                 }
 322                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 323                                 str.size());
 324                 curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS,
 325                                 str.c_str());
 326         } else {
 327                 curl_easy_setopt(curl, CURLOPT_POST, 1);
 328                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 329                                 request.post_data.size());
 330                 curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
 331                                 request.post_data.c_str());
 332                 // request.post_data must now *never* be
 333                 // modified until CURLOPT_POSTFIELDS is cleared
 334         }
 335         // Set additional HTTP headers
 336         for (std::vector<std::string>::iterator it = request.extra_headers.begin();
 337                         it != request.extra_headers.end(); ++it) {
 338                 http_header = curl_slist_append(http_header, it->c_str());
 339         }
 340         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, http_header);
 341
 342         if (!g_settings->getBool("curl_verify_cert")) {
 343                 curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
 344         }
 345 }
 346
 347 CURLcode HTTPFetchOngoing::start(CURLM *multi_)
 348 {
 349         if (!curl)
 350                 return CURLE_FAILED_INIT;
 351
 352         if (!multi_) {
 353                 // Easy interface (sync)
 354                 return curl_easy_perform(curl);
 355         }
 356
 357         // Multi interface (async)
 358         CURLMcode mres = curl_multi_add_handle(multi_, curl);
 359         if (mres != CURLM_OK) {
 360                 errorstream << "curl_multi_add_handle"
 361                         << " returned error code " << mres
 362                         << std::endl;
 363                 return CURLE_FAILED_INIT;
 364         }
 365         multi = multi_; // store for curl_multi_remove_handle
 366         return CURLE_OK;
 367 }
 368
 369 const HTTPFetchResult * HTTPFetchOngoing::complete(CURLcode res)
 370 {
 371         result.succeeded = (res == CURLE_OK);
 372         result.timeout = (res == CURLE_OPERATION_TIMEDOUT);
 373         result.data = oss.str();
 374
 375         // Get HTTP/FTP response code
 376         result.response_code = 0;
 377         if (curl && (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE,
 378                                 &result.response_code) != CURLE_OK)) {
 379                 // We failed to get a return code, make sure it is still 0
 380                 result.response_code = 0;
 381         }
 382
 383         if (res != CURLE_OK) {
 384                 errorstream << request.url << " not found ("
 385                         << curl_easy_strerror(res) << ")"
 386                         << " (response code " << result.response_code << ")"
 387                         << std::endl;
 388         }
 389
 390         return &result;
 391 }
 392
 393 HTTPFetchOngoing::~HTTPFetchOngoing()
 394 {
 395         if (multi) {
 396                 CURLMcode mres = curl_multi_remove_handle(multi, curl);
 397                 if (mres != CURLM_OK) {
 398                         errorstream << "curl_multi_remove_handle"
 399                                 << " returned error code " << mres
 400                                 << std::endl;
 401                 }
 402         }
 403
 404         // Set safe options for the reusable cURL handle
 405         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 406                         httpfetch_discardfunction);
 407         curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 408         curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
 409         if (http_header) {
 410                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, NULL);
 411                 curl_slist_free_all(http_header);
 412         }
 413         if (post) {
 414                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, NULL);
 415                 curl_formfree(post);
 416         }
 417
 418         // Store the cURL handle for reuse
 419         pool->free(curl);
 420 }
 421
 422
 423 class CurlFetchThread : public Thread
 424 {
 425 protected:
 426         enum RequestType {
 427                 RT_FETCH,
 428                 RT_CLEAR,
 429                 RT_WAKEUP,
 430         };
 431
 432         struct Request {
 433                 RequestType type;
 434                 HTTPFetchRequest fetch_request;
 435                 Event *event;
 436         };
 437
 438         CURLM *m_multi;
 439         MutexedQueue<Request> m_requests;
 440         size_t m_parallel_limit;
 441
 442         // Variables exclusively used within thread
 443         std::vector<HTTPFetchOngoing*> m_all_ongoing;
 444         std::list<HTTPFetchRequest> m_queued_fetches;
 445
 446 public:
 447         CurlFetchThread(int parallel_limit) :
 448                 Thread("CurlFetch")
 449         {
 450                 if (parallel_limit >= 1)
 451                         m_parallel_limit = parallel_limit;
 452                 else
 453                         m_parallel_limit = 1;
 454         }
 455
 456         void requestFetch(const HTTPFetchRequest &fetch_request)
 457         {
 458                 Request req;
 459                 req.type = RT_FETCH;
 460                 req.fetch_request = fetch_request;
 461                 req.event = NULL;
 462                 m_requests.push_back(req);
 463         }
 464
 465         void requestClear(unsigned long caller, Event *event)
 466         {
 467                 Request req;
 468                 req.type = RT_CLEAR;
 469                 req.fetch_request.caller = caller;
 470                 req.event = event;
 471                 m_requests.push_back(req);
 472         }
 473
 474         void requestWakeUp()
 475         {
 476                 Request req;
 477                 req.type = RT_WAKEUP;
 478                 req.event = NULL;
 479                 m_requests.push_back(req);
 480         }
 481
 482 protected:
 483         // Handle a request from some other thread
 484         // E.g. new fetch; clear fetches for one caller; wake up
 485         void processRequest(const Request &req)
 486         {
 487                 if (req.type == RT_FETCH) {
 488                         // New fetch, queue until there are less
 489                         // than m_parallel_limit ongoing fetches
 490                         m_queued_fetches.push_back(req.fetch_request);
 491
 492                         // see processQueued() for what happens next
 493
 494                 }
 495                 else if (req.type == RT_CLEAR) {
 496                         unsigned long caller = req.fetch_request.caller;
 497
 498                         // Abort all ongoing fetches for the caller
 499                         for (std::vector<HTTPFetchOngoing*>::iterator
 500                                         it = m_all_ongoing.begin();
 501                                         it != m_all_ongoing.end();) {
 502                                 if ((*it)->getRequest().caller == caller) {
 503                                         delete (*it);
 504                                         it = m_all_ongoing.erase(it);
 505                                 } else {
 506                                         ++it;
 507                                 }
 508                         }
 509
 510                         // Also abort all queued fetches for the caller
 511                         for (std::list<HTTPFetchRequest>::iterator
 512                                         it = m_queued_fetches.begin();
 513                                         it != m_queued_fetches.end();) {
 514                                 if ((*it).caller == caller)
 515                                         it = m_queued_fetches.erase(it);
 516                                 else
 517                                         ++it;
 518                         }
 519                 }
 520                 else if (req.type == RT_WAKEUP) {
 521                         // Wakeup: Nothing to do, thread is awake at this point
 522                 }
 523
 524                 if (req.event != NULL)
 525                         req.event->signal();
 526         }
 527
 528         // Start new ongoing fetches if m_parallel_limit allows
 529         void processQueued(CurlHandlePool *pool)
 530         {
 531                 while (m_all_ongoing.size() < m_parallel_limit &&
 532                                 !m_queued_fetches.empty()) {
 533                         HTTPFetchRequest request = m_queued_fetches.front();
 534                         m_queued_fetches.pop_front();
 535
 536                         // Create ongoing fetch data and make a cURL handle
 537                         // Set cURL options based on HTTPFetchRequest
 538                         HTTPFetchOngoing *ongoing =
 539                                 new HTTPFetchOngoing(request, pool);
 540
 541                         // Initiate the connection (curl_multi_add_handle)
 542                         CURLcode res = ongoing->start(m_multi);
 543                         if (res == CURLE_OK) {
 544                                 m_all_ongoing.push_back(ongoing);
 545                         }
 546                         else {
 547                                 httpfetch_deliver_result(*ongoing->complete(res));
 548                                 delete ongoing;
 549                         }
 550                 }
 551         }
 552
 553         // Process CURLMsg (indicates completion of a fetch)
 554         void processCurlMessage(CURLMsg *msg)
 555         {
 556                 // Determine which ongoing fetch the message pertains to
 557                 size_t i = 0;
 558                 bool found = false;
 559                 for (i = 0; i < m_all_ongoing.size(); ++i) {
 560                         if (m_all_ongoing[i]->getEasyHandle() == msg->easy_handle) {
 561                                 found = true;
 562                                 break;
 563                         }
 564                 }
 565                 if (msg->msg == CURLMSG_DONE && found) {
 566                         // m_all_ongoing[i] succeeded or failed.
 567                         HTTPFetchOngoing *ongoing = m_all_ongoing[i];
 568                         httpfetch_deliver_result(*ongoing->complete(msg->data.result));
 569                         delete ongoing;
 570                         m_all_ongoing.erase(m_all_ongoing.begin() + i);
 571                 }
 572         }
 573
 574         // Wait for a request from another thread, or timeout elapses
 575         void waitForRequest(long timeout)
 576         {
 577                 if (m_queued_fetches.empty()) {
 578                         try {
 579                                 Request req = m_requests.pop_front(timeout);
 580                                 processRequest(req);
 581                         }
 582                         catch (ItemNotFoundException &e) {}
 583                 }
 584         }
 585
 586         // Wait until some IO happens, or timeout elapses
 587         void waitForIO(long timeout)
 588         {
 589                 fd_set read_fd_set;
 590                 fd_set write_fd_set;
 591                 fd_set exc_fd_set;
 592                 int max_fd;
 593                 long select_timeout = -1;
 594                 struct timeval select_tv;
 595                 CURLMcode mres;
 596
 597                 FD_ZERO(&read_fd_set);
 598                 FD_ZERO(&write_fd_set);
 599                 FD_ZERO(&exc_fd_set);
 600
 601                 mres = curl_multi_fdset(m_multi, &read_fd_set,
 602                                 &write_fd_set, &exc_fd_set, &max_fd);
 603                 if (mres != CURLM_OK) {
 604                         errorstream<<"curl_multi_fdset"
 605                                 <<" returned error code "<<mres
 606                                 <<std::endl;
 607                         select_timeout = 0;
 608                 }
 609
 610                 mres = curl_multi_timeout(m_multi, &select_timeout);
 611                 if (mres != CURLM_OK) {
 612                         errorstream<<"curl_multi_timeout"
 613                                 <<" returned error code "<<mres
 614                                 <<std::endl;
 615                         select_timeout = 0;
 616                 }
 617
 618                 // Limit timeout so new requests get through
 619                 if (select_timeout < 0 || select_timeout > timeout)
 620                         select_timeout = timeout;
 621
 622                 if (select_timeout > 0) {
 623                         // in Winsock it is forbidden to pass three empty
 624                         // fd_sets to select(), so in that case use sleep_ms
 625                         if (max_fd != -1) {
 626                                 select_tv.tv_sec = select_timeout / 1000;
 627                                 select_tv.tv_usec = (select_timeout % 1000) * 1000;
 628                                 int retval = select(max_fd + 1, &read_fd_set,
 629                                                 &write_fd_set, &exc_fd_set,
 630                                                 &select_tv);
 631                                 if (retval == -1) {
 632                                         #ifdef _WIN32
 633                                         errorstream<<"select returned error code "
 634                                                 <<WSAGetLastError()<<std::endl;
 635                                         #else
 636                                         errorstream<<"select returned error code "
 637                                                 <<errno<<std::endl;
 638                                         #endif
 639                                 }
 640                         }
 641                         else {
 642                                 sleep_ms(select_timeout);
 643                         }
 644                 }
 645         }
 646
 647         void *run()
 648         {
 649                 DSTACK(FUNCTION_NAME);
 650
 651                 CurlHandlePool pool;
 652
 653                 m_multi = curl_multi_init();
 654                 if (m_multi == NULL) {
 655                         errorstream<<"curl_multi_init returned NULL\n";
 656                         return NULL;
 657                 }
 658
 659                 FATAL_ERROR_IF(!m_all_ongoing.empty(), "Expected empty");
 660
 661                 while (!stopRequested()) {
 662                         BEGIN_DEBUG_EXCEPTION_HANDLER
 663
 664                         /*
 665                                 Handle new async requests
 666                         */
 667
 668                         while (!m_requests.empty()) {
 669                                 Request req = m_requests.pop_frontNoEx();
 670                                 processRequest(req);
 671                         }
 672                         processQueued(&pool);
 673
 674                         /*
 675                                 Handle ongoing async requests
 676                         */
 677
 678                         int still_ongoing = 0;
 679                         while (curl_multi_perform(m_multi, &still_ongoing) ==
 680                                         CURLM_CALL_MULTI_PERFORM)
 681                                 /* noop */;
 682
 683                         /*
 684                                 Handle completed async requests
 685                         */
 686                         if (still_ongoing < (int) m_all_ongoing.size()) {
 687                                 CURLMsg *msg;
 688                                 int msgs_in_queue;
 689                                 msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 690                                 while (msg != NULL) {
 691                                         processCurlMessage(msg);
 692                                         msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 693                                 }
 694                         }
 695
 696                         /*
 697                                 If there are ongoing requests, wait for data
 698                                 (with a timeout of 100ms so that new requests
 699                                 can be processed).
 700
 701                                 If no ongoing requests, wait for a new request.
 702                                 (Possibly an empty request that signals
 703                                 that the thread should be stopped.)
 704                         */
 705                         if (m_all_ongoing.empty())
 706                                 waitForRequest(100000000);
 707                         else
 708                                 waitForIO(100);
 709
 710                         END_DEBUG_EXCEPTION_HANDLER
 711                 }
 712
 713                 // Call curl_multi_remove_handle and cleanup easy handles
 714                 for (size_t i = 0; i < m_all_ongoing.size(); ++i) {
 715                         delete m_all_ongoing[i];
 716                 }
 717                 m_all_ongoing.clear();
 718
 719                 m_queued_fetches.clear();
 720
 721                 CURLMcode mres = curl_multi_cleanup(m_multi);
 722                 if (mres != CURLM_OK) {
 723                         errorstream<<"curl_multi_cleanup"
 724                                 <<" returned error code "<<mres
 725                                 <<std::endl;
 726                 }
 727
 728                 return NULL;
 729         }
 730 };
 731
 732 CurlFetchThread *g_httpfetch_thread = NULL;
 733
 734 void httpfetch_init(int parallel_limit)
 735 {
 736         verbosestream<<"httpfetch_init: parallel_limit="<<parallel_limit
 737                         <<std::endl;
 738
 739         CURLcode res = curl_global_init(CURL_GLOBAL_DEFAULT);
 740         FATAL_ERROR_IF(res != CURLE_OK, "CURL init failed");
 741
 742         g_httpfetch_thread = new CurlFetchThread(parallel_limit);
 743
 744         // Initialize g_callerid_randomness for httpfetch_caller_alloc_secure
 745         u64 randbuf[2];
 746         porting::secure_rand_fill_buf(randbuf, sizeof(u64) * 2);
 747         g_callerid_randomness = PcgRandom(randbuf[0], randbuf[1]);
 748 }
 749
 750 void httpfetch_cleanup()
 751 {
 752         verbosestream<<"httpfetch_cleanup: cleaning up"<<std::endl;
 753
 754         g_httpfetch_thread->stop();
 755         g_httpfetch_thread->requestWakeUp();
 756         g_httpfetch_thread->wait();
 757         delete g_httpfetch_thread;
 758
 759         curl_global_cleanup();
 760 }
 761
 762 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 763 {
 764         g_httpfetch_thread->requestFetch(fetch_request);
 765         if (!g_httpfetch_thread->isRunning())
 766                 g_httpfetch_thread->start();
 767 }
 768
 769 static void httpfetch_request_clear(unsigned long caller)
 770 {
 771         if (g_httpfetch_thread->isRunning()) {
 772                 Event event;
 773                 g_httpfetch_thread->requestClear(caller, &event);
 774                 event.wait();
 775         } else {
 776                 g_httpfetch_thread->requestClear(caller, NULL);
 777         }
 778 }
 779
 780 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 781                 HTTPFetchResult &fetch_result)
 782 {
 783         // Create ongoing fetch data and make a cURL handle
 784         // Set cURL options based on HTTPFetchRequest
 785         CurlHandlePool pool;
 786         HTTPFetchOngoing ongoing(fetch_request, &pool);
 787         // Do the fetch (curl_easy_perform)
 788         CURLcode res = ongoing.start(NULL);
 789         // Update fetch result
 790         fetch_result = *ongoing.complete(res);
 791 }
 792
 793 #else  // USE_CURL
 794
 795 /*
 796         USE_CURL is off:
 797
 798         Dummy httpfetch implementation that always returns an error.
 799 */
 800
 801 void httpfetch_init(int parallel_limit)
 802 {
 803 }
 804
 805 void httpfetch_cleanup()
 806 {
 807 }
 808
 809 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 810 {
 811         errorstream << "httpfetch_async: unable to fetch " << fetch_request.url
 812                         << " because USE_CURL=0" << std::endl;
 813
 814         HTTPFetchResult fetch_result(fetch_request); // sets succeeded = false etc.
 815         httpfetch_deliver_result(fetch_result);
 816 }
 817
 818 static void httpfetch_request_clear(unsigned long caller)
 819 {
 820 }
 821
 822 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 823                 HTTPFetchResult &fetch_result)
 824 {
 825         errorstream << "httpfetch_sync: unable to fetch " << fetch_request.url
 826                         << " because USE_CURL=0" << std::endl;
 827
 828         fetch_result = HTTPFetchResult(fetch_request); // sets succeeded = false etc.
 829 }
 830
 831 #endif  // USE_CURL