src/util.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2017 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #include <util.h>
   7
   8 #include <chainparamsbase.h>
   9 #include <random.h>
  10 #include <serialize.h>
  11 #include <utilstrencodings.h>
  12
  13 #include <stdarg.h>
  14
  15 #if (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
  16 #include <pthread.h>
  17 #include <pthread_np.h>
  18 #endif
  19
  20 #ifndef WIN32
  21 // for posix_fallocate
  22 #ifdef __linux__
  23
  24 #ifdef _POSIX_C_SOURCE
  25 #undef _POSIX_C_SOURCE
  26 #endif
  27
  28 #define _POSIX_C_SOURCE 200112L
  29
  30 #endif // __linux__
  31
  32 #include <algorithm>
  33 #include <fcntl.h>
  34 #include <sys/resource.h>
  35 #include <sys/stat.h>
  36
  37 #else
  38
  39 #ifdef _MSC_VER
  40 #pragma warning(disable:4786)
  41 #pragma warning(disable:4804)
  42 #pragma warning(disable:4805)
  43 #pragma warning(disable:4717)
  44 #endif
  45
  46 #ifdef _WIN32_WINNT
  47 #undef _WIN32_WINNT
  48 #endif
  49 #define _WIN32_WINNT 0x0501
  50
  51 #ifdef _WIN32_IE
  52 #undef _WIN32_IE
  53 #endif
  54 #define _WIN32_IE 0x0501
  55
  56 #define WIN32_LEAN_AND_MEAN 1
  57 #ifndef NOMINMAX
  58 #define NOMINMAX
  59 #endif
  60
  61 #include <io.h> /* for _commit */
  62 #include <shlobj.h>
  63 #endif
  64
  65 #ifdef HAVE_SYS_PRCTL_H
  66 #include <sys/prctl.h>
  67 #endif
  68
  69 #ifdef HAVE_MALLOPT_ARENA_MAX
  70 #include <malloc.h>
  71 #endif
  72
  73 #include <boost/algorithm/string/case_conv.hpp> // for to_lower()
  74 #include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
  75 #include <boost/program_options/detail/config_file.hpp>
  76 #include <boost/thread.hpp>
  77 #include <openssl/crypto.h>
  78 #include <openssl/rand.h>
  79 #include <openssl/conf.h>
  80
  81 // Application startup time (used for uptime calculation)
  82 const int64_t nStartupTime = GetTime();
  83
  84 const char * const BITCOIN_CONF_FILENAME = "bitcoin.conf";
  85 const char * const BITCOIN_PID_FILENAME = "bitcoind.pid";
  86 const char * const DEFAULT_DEBUGLOGFILE = "debug.log";
  87
  88 ArgsManager gArgs;
  89 bool fPrintToConsole = false;
  90 bool fPrintToDebugLog = true;
  91
  92 bool fLogTimestamps = DEFAULT_LOGTIMESTAMPS;
  93 bool fLogTimeMicros = DEFAULT_LOGTIMEMICROS;
  94 bool fLogIPs = DEFAULT_LOGIPS;
  95 std::atomic<bool> fReopenDebugLog(false);
  96 CTranslationInterface translationInterface;
  97
  98 /** Log categories bitfield. */
  99 std::atomic<uint32_t> logCategories(0);
 100
 101 /** Init OpenSSL library multithreading support */
 102 static std::unique_ptr<CCriticalSection[]> ppmutexOpenSSL;
 103 void locking_callback(int mode, int i, const char* file, int line) NO_THREAD_SAFETY_ANALYSIS
 104 {
 105     if (mode & CRYPTO_LOCK) {
 106         ENTER_CRITICAL_SECTION(ppmutexOpenSSL[i]);
 107     } else {
 108         LEAVE_CRITICAL_SECTION(ppmutexOpenSSL[i]);
 109     }
 110 }
 111
 112 // Singleton for wrapping OpenSSL setup/teardown.
 113 class CInit
 114 {
 115 public:
 116     CInit()
 117     {
 118         // Init OpenSSL library multithreading support
 119         ppmutexOpenSSL.reset(new CCriticalSection[CRYPTO_num_locks()]);
 120         CRYPTO_set_locking_callback(locking_callback);
 121
 122         // OpenSSL can optionally load a config file which lists optional loadable modules and engines.
 123         // We don't use them so we don't require the config. However some of our libs may call functions
 124         // which attempt to load the config file, possibly resulting in an exit() or crash if it is missing
 125         // or corrupt. Explicitly tell OpenSSL not to try to load the file. The result for our libs will be
 126         // that the config appears to have been loaded and there are no modules/engines available.
 127         OPENSSL_no_config();
 128
 129 #ifdef WIN32
 130         // Seed OpenSSL PRNG with current contents of the screen
 131         RAND_screen();
 132 #endif
 133
 134         // Seed OpenSSL PRNG with performance counter
 135         RandAddSeed();
 136     }
 137     ~CInit()
 138     {
 139         // Securely erase the memory used by the PRNG
 140         RAND_cleanup();
 141         // Shutdown OpenSSL library multithreading support
 142         CRYPTO_set_locking_callback(nullptr);
 143         // Clear the set of locks now to maintain symmetry with the constructor.
 144         ppmutexOpenSSL.reset();
 145     }
 146 }
 147 instance_of_cinit;
 148
 149 /**
 150  * LogPrintf() has been broken a couple of times now
 151  * by well-meaning people adding mutexes in the most straightforward way.
 152  * It breaks because it may be called by global destructors during shutdown.
 153  * Since the order of destruction of static/global objects is undefined,
 154  * defining a mutex as a global object doesn't work (the mutex gets
 155  * destroyed, and then some later destructor calls OutputDebugStringF,
 156  * maybe indirectly, and you get a core dump at shutdown trying to lock
 157  * the mutex).
 158  */
 159
 160 static boost::once_flag debugPrintInitFlag = BOOST_ONCE_INIT;
 161
 162 /**
 163  * We use boost::call_once() to make sure mutexDebugLog and
 164  * vMsgsBeforeOpenLog are initialized in a thread-safe manner.
 165  *
 166  * NOTE: fileout, mutexDebugLog and sometimes vMsgsBeforeOpenLog
 167  * are leaked on exit. This is ugly, but will be cleaned up by
 168  * the OS/libc. When the shutdown sequence is fully audited and
 169  * tested, explicit destruction of these objects can be implemented.
 170  */
 171 static FILE* fileout = nullptr;
 172 static boost::mutex* mutexDebugLog = nullptr;
 173 static std::list<std::string>* vMsgsBeforeOpenLog;
 174
 175 static int FileWriteStr(const std::string &str, FILE *fp)
 176 {
 177     return fwrite(str.data(), 1, str.size(), fp);
 178 }
 179
 180 static void DebugPrintInit()
 181 {
 182     assert(mutexDebugLog == nullptr);
 183     mutexDebugLog = new boost::mutex();
 184     vMsgsBeforeOpenLog = new std::list<std::string>;
 185 }
 186
 187 fs::path GetDebugLogPath()
 188 {
 189     fs::path logfile(gArgs.GetArg("-debuglogfile", DEFAULT_DEBUGLOGFILE));
 190     if (logfile.is_absolute()) {
 191         return logfile;
 192     } else {
 193         return GetDataDir() / logfile;
 194     }
 195 }
 196
 197 bool OpenDebugLog()
 198 {
 199     boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 200     boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 201
 202     assert(fileout == nullptr);
 203     assert(vMsgsBeforeOpenLog);
 204     fs::path pathDebug = GetDebugLogPath();
 205
 206     fileout = fsbridge::fopen(pathDebug, "a");
 207     if (!fileout) {
 208         return false;
 209     }
 210
 211     setbuf(fileout, nullptr); // unbuffered
 212     // dump buffered messages from before we opened the log
 213     while (!vMsgsBeforeOpenLog->empty()) {
 214         FileWriteStr(vMsgsBeforeOpenLog->front(), fileout);
 215         vMsgsBeforeOpenLog->pop_front();
 216     }
 217
 218     delete vMsgsBeforeOpenLog;
 219     vMsgsBeforeOpenLog = nullptr;
 220     return true;
 221 }
 222
 223 struct CLogCategoryDesc
 224 {
 225     uint32_t flag;
 226     std::string category;
 227 };
 228
 229 const CLogCategoryDesc LogCategories[] =
 230 {
 231     {BCLog::NONE, "0"},
 232     {BCLog::NONE, "none"},
 233     {BCLog::NET, "net"},
 234     {BCLog::TOR, "tor"},
 235     {BCLog::MEMPOOL, "mempool"},
 236     {BCLog::HTTP, "http"},
 237     {BCLog::BENCH, "bench"},
 238     {BCLog::ZMQ, "zmq"},
 239     {BCLog::DB, "db"},
 240     {BCLog::RPC, "rpc"},
 241     {BCLog::ESTIMATEFEE, "estimatefee"},
 242     {BCLog::ADDRMAN, "addrman"},
 243     {BCLog::SELECTCOINS, "selectcoins"},
 244     {BCLog::REINDEX, "reindex"},
 245     {BCLog::CMPCTBLOCK, "cmpctblock"},
 246     {BCLog::RAND, "rand"},
 247     {BCLog::PRUNE, "prune"},
 248     {BCLog::PROXY, "proxy"},
 249     {BCLog::MEMPOOLREJ, "mempoolrej"},
 250     {BCLog::LIBEVENT, "libevent"},
 251     {BCLog::COINDB, "coindb"},
 252     {BCLog::QT, "qt"},
 253     {BCLog::LEVELDB, "leveldb"},
 254     {BCLog::ALL, "1"},
 255     {BCLog::ALL, "all"},
 256 };
 257
 258 bool GetLogCategory(uint32_t *f, const std::string *str)
 259 {
 260     if (f && str) {
 261         if (*str == "") {
 262             *f = BCLog::ALL;
 263             return true;
 264         }
 265         for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 266             if (LogCategories[i].category == *str) {
 267                 *f = LogCategories[i].flag;
 268                 return true;
 269             }
 270         }
 271     }
 272     return false;
 273 }
 274
 275 std::string ListLogCategories()
 276 {
 277     std::string ret;
 278     int outcount = 0;
 279     for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 280         // Omit the special cases.
 281         if (LogCategories[i].flag != BCLog::NONE && LogCategories[i].flag != BCLog::ALL) {
 282             if (outcount != 0) ret += ", ";
 283             ret += LogCategories[i].category;
 284             outcount++;
 285         }
 286     }
 287     return ret;
 288 }
 289
 290 std::vector<CLogCategoryActive> ListActiveLogCategories()
 291 {
 292     std::vector<CLogCategoryActive> ret;
 293     for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 294         // Omit the special cases.
 295         if (LogCategories[i].flag != BCLog::NONE && LogCategories[i].flag != BCLog::ALL) {
 296             CLogCategoryActive catActive;
 297             catActive.category = LogCategories[i].category;
 298             catActive.active = LogAcceptCategory(LogCategories[i].flag);
 299             ret.push_back(catActive);
 300         }
 301     }
 302     return ret;
 303 }
 304
 305 /**
 306  * fStartedNewLine is a state variable held by the calling context that will
 307  * suppress printing of the timestamp when multiple calls are made that don't
 308  * end in a newline. Initialize it to true, and hold it, in the calling context.
 309  */
 310 static std::string LogTimestampStr(const std::string &str, std::atomic_bool *fStartedNewLine)
 311 {
 312     std::string strStamped;
 313
 314     if (!fLogTimestamps)
 315         return str;
 316
 317     if (*fStartedNewLine) {
 318         int64_t nTimeMicros = GetTimeMicros();
 319         strStamped = DateTimeStrFormat("%Y-%m-%d %H:%M:%S", nTimeMicros/1000000);
 320         if (fLogTimeMicros)
 321             strStamped += strprintf(".%06d", nTimeMicros%1000000);
 322         int64_t mocktime = GetMockTime();
 323         if (mocktime) {
 324             strStamped += " (mocktime: " + DateTimeStrFormat("%Y-%m-%d %H:%M:%S", mocktime) + ")";
 325         }
 326         strStamped += ' ' + str;
 327     } else
 328         strStamped = str;
 329
 330     if (!str.empty() && str[str.size()-1] == '\n')
 331         *fStartedNewLine = true;
 332     else
 333         *fStartedNewLine = false;
 334
 335     return strStamped;
 336 }
 337
 338 int LogPrintStr(const std::string &str)
 339 {
 340     int ret = 0; // Returns total number of characters written
 341     static std::atomic_bool fStartedNewLine(true);
 342
 343     std::string strTimestamped = LogTimestampStr(str, &fStartedNewLine);
 344
 345     if (fPrintToConsole)
 346     {
 347         // print to console
 348         ret = fwrite(strTimestamped.data(), 1, strTimestamped.size(), stdout);
 349         fflush(stdout);
 350     }
 351     else if (fPrintToDebugLog)
 352     {
 353         boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 354         boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 355
 356         // buffer if we haven't opened the log yet
 357         if (fileout == nullptr) {
 358             assert(vMsgsBeforeOpenLog);
 359             ret = strTimestamped.length();
 360             vMsgsBeforeOpenLog->push_back(strTimestamped);
 361         }
 362         else
 363         {
 364             // reopen the log file, if requested
 365             if (fReopenDebugLog) {
 366                 fReopenDebugLog = false;
 367                 fs::path pathDebug = GetDebugLogPath();
 368                 if (fsbridge::freopen(pathDebug,"a",fileout) != nullptr)
 369                     setbuf(fileout, nullptr); // unbuffered
 370             }
 371
 372             ret = FileWriteStr(strTimestamped, fileout);
 373         }
 374     }
 375     return ret;
 376 }
 377
 378 /** Interpret string as boolean, for argument parsing */
 379 static bool InterpretBool(const std::string& strValue)
 380 {
 381     if (strValue.empty())
 382         return true;
 383     return (atoi(strValue) != 0);
 384 }
 385
 386 /** Turn -noX into -X=0 */
 387 static void InterpretNegativeSetting(std::string& strKey, std::string& strValue)
 388 {
 389     if (strKey.length()>3 && strKey[0]=='-' && strKey[1]=='n' && strKey[2]=='o')
 390     {
 391         strKey = "-" + strKey.substr(3);
 392         strValue = InterpretBool(strValue) ? "0" : "1";
 393     }
 394 }
 395
 396 void ArgsManager::ParseParameters(int argc, const char* const argv[])
 397 {
 398     LOCK(cs_args);
 399     mapArgs.clear();
 400     mapMultiArgs.clear();
 401
 402     for (int i = 1; i < argc; i++)
 403     {
 404         std::string str(argv[i]);
 405         std::string strValue;
 406         size_t is_index = str.find('=');
 407         if (is_index != std::string::npos)
 408         {
 409             strValue = str.substr(is_index+1);
 410             str = str.substr(0, is_index);
 411         }
 412 #ifdef WIN32
 413         boost::to_lower(str);
 414         if (boost::algorithm::starts_with(str, "/"))
 415             str = "-" + str.substr(1);
 416 #endif
 417
 418         if (str[0] != '-')
 419             break;
 420
 421         // Interpret --foo as -foo.
 422         // If both --foo and -foo are set, the last takes effect.
 423         if (str.length() > 1 && str[1] == '-')
 424             str = str.substr(1);
 425         InterpretNegativeSetting(str, strValue);
 426
 427         mapArgs[str] = strValue;
 428         mapMultiArgs[str].push_back(strValue);
 429     }
 430 }
 431
 432 std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg) const
 433 {
 434     LOCK(cs_args);
 435     auto it = mapMultiArgs.find(strArg);
 436     if (it != mapMultiArgs.end()) return it->second;
 437     return {};
 438 }
 439
 440 bool ArgsManager::IsArgSet(const std::string& strArg) const
 441 {
 442     LOCK(cs_args);
 443     return mapArgs.count(strArg);
 444 }
 445
 446 std::string ArgsManager::GetArg(const std::string& strArg, const std::string& strDefault) const
 447 {
 448     LOCK(cs_args);
 449     auto it = mapArgs.find(strArg);
 450     if (it != mapArgs.end()) return it->second;
 451     return strDefault;
 452 }
 453
 454 int64_t ArgsManager::GetArg(const std::string& strArg, int64_t nDefault) const
 455 {
 456     LOCK(cs_args);
 457     auto it = mapArgs.find(strArg);
 458     if (it != mapArgs.end()) return atoi64(it->second);
 459     return nDefault;
 460 }
 461
 462 bool ArgsManager::GetBoolArg(const std::string& strArg, bool fDefault) const
 463 {
 464     LOCK(cs_args);
 465     auto it = mapArgs.find(strArg);
 466     if (it != mapArgs.end()) return InterpretBool(it->second);
 467     return fDefault;
 468 }
 469
 470 bool ArgsManager::SoftSetArg(const std::string& strArg, const std::string& strValue)
 471 {
 472     LOCK(cs_args);
 473     if (IsArgSet(strArg)) return false;
 474     ForceSetArg(strArg, strValue);
 475     return true;
 476 }
 477
 478 bool ArgsManager::SoftSetBoolArg(const std::string& strArg, bool fValue)
 479 {
 480     if (fValue)
 481         return SoftSetArg(strArg, std::string("1"));
 482     else
 483         return SoftSetArg(strArg, std::string("0"));
 484 }
 485
 486 void ArgsManager::ForceSetArg(const std::string& strArg, const std::string& strValue)
 487 {
 488     LOCK(cs_args);
 489     mapArgs[strArg] = strValue;
 490     mapMultiArgs[strArg] = {strValue};
 491 }
 492
 493
 494
 495 static const int screenWidth = 79;
 496 static const int optIndent = 2;
 497 static const int msgIndent = 7;
 498
 499 std::string HelpMessageGroup(const std::string &message) {
 500     return std::string(message) + std::string("\n\n");
 501 }
 502
 503 std::string HelpMessageOpt(const std::string &option, const std::string &message) {
 504     return std::string(optIndent,' ') + std::string(option) +
 505            std::string("\n") + std::string(msgIndent,' ') +
 506            FormatParagraph(message, screenWidth - msgIndent, msgIndent) +
 507            std::string("\n\n");
 508 }
 509
 510 static std::string FormatException(const std::exception* pex, const char* pszThread)
 511 {
 512 #ifdef WIN32
 513     char pszModule[MAX_PATH] = "";
 514     GetModuleFileNameA(nullptr, pszModule, sizeof(pszModule));
 515 #else
 516     const char* pszModule = "bitcoin";
 517 #endif
 518     if (pex)
 519         return strprintf(
 520             "EXCEPTION: %s       \n%s       \n%s in %s       \n", typeid(*pex).name(), pex->what(), pszModule, pszThread);
 521     else
 522         return strprintf(
 523             "UNKNOWN EXCEPTION       \n%s in %s       \n", pszModule, pszThread);
 524 }
 525
 526 void PrintExceptionContinue(const std::exception* pex, const char* pszThread)
 527 {
 528     std::string message = FormatException(pex, pszThread);
 529     LogPrintf("\n\n************************\n%s\n", message);
 530     fprintf(stderr, "\n\n************************\n%s\n", message.c_str());
 531 }
 532
 533 fs::path GetDefaultDataDir()
 534 {
 535     // Windows < Vista: C:\Documents and Settings\Username\Application Data\Bitcoin
 536     // Windows >= Vista: C:\Users\Username\AppData\Roaming\Bitcoin
 537     // Mac: ~/Library/Application Support/Bitcoin
 538     // Unix: ~/.bitcoin
 539 #ifdef WIN32
 540     // Windows
 541     return GetSpecialFolderPath(CSIDL_APPDATA) / "Bitcoin";
 542 #else
 543     fs::path pathRet;
 544     char* pszHome = getenv("HOME");
 545     if (pszHome == nullptr || strlen(pszHome) == 0)
 546         pathRet = fs::path("/");
 547     else
 548         pathRet = fs::path(pszHome);
 549 #ifdef MAC_OSX
 550     // Mac
 551     return pathRet / "Library/Application Support/Bitcoin";
 552 #else
 553     // Unix
 554     return pathRet / ".bitcoin";
 555 #endif
 556 #endif
 557 }
 558
 559 static fs::path pathCached;
 560 static fs::path pathCachedNetSpecific;
 561 static CCriticalSection csPathCached;
 562
 563 const fs::path &GetDataDir(bool fNetSpecific)
 564 {
 565
 566     LOCK(csPathCached);
 567
 568     fs::path &path = fNetSpecific ? pathCachedNetSpecific : pathCached;
 569
 570     // This can be called during exceptions by LogPrintf(), so we cache the
 571     // value so we don't have to do memory allocations after that.
 572     if (!path.empty())
 573         return path;
 574
 575     if (gArgs.IsArgSet("-datadir")) {
 576         path = fs::system_complete(gArgs.GetArg("-datadir", ""));
 577         if (!fs::is_directory(path)) {
 578             path = "";
 579             return path;
 580         }
 581     } else {
 582         path = GetDefaultDataDir();
 583     }
 584     if (fNetSpecific)
 585         path /= BaseParams().DataDir();
 586
 587     if (fs::create_directories(path)) {
 588         // This is the first run, create wallets subdirectory too
 589         fs::create_directories(path / "wallets");
 590     }
 591
 592     return path;
 593 }
 594
 595 void ClearDatadirCache()
 596 {
 597     LOCK(csPathCached);
 598
 599     pathCached = fs::path();
 600     pathCachedNetSpecific = fs::path();
 601 }
 602
 603 fs::path GetConfigFile(const std::string& confPath)
 604 {
 605     fs::path pathConfigFile(confPath);
 606     if (!pathConfigFile.is_complete())
 607         pathConfigFile = GetDataDir(false) / pathConfigFile;
 608
 609     return pathConfigFile;
 610 }
 611
 612 void ArgsManager::ReadConfigFile(const std::string& confPath)
 613 {
 614     fs::ifstream streamConfig(GetConfigFile(confPath));
 615     if (!streamConfig.good())
 616         return; // No bitcoin.conf file is OK
 617
 618     {
 619         LOCK(cs_args);
 620         std::set<std::string> setOptions;
 621         setOptions.insert("*");
 622
 623         for (boost::program_options::detail::config_file_iterator it(streamConfig, setOptions), end; it != end; ++it)
 624         {
 625             // Don't overwrite existing settings so command line settings override bitcoin.conf
 626             std::string strKey = std::string("-") + it->string_key;
 627             std::string strValue = it->value[0];
 628             InterpretNegativeSetting(strKey, strValue);
 629             if (mapArgs.count(strKey) == 0)
 630                 mapArgs[strKey] = strValue;
 631             mapMultiArgs[strKey].push_back(strValue);
 632         }
 633     }
 634     // If datadir is changed in .conf file:
 635     ClearDatadirCache();
 636     if (!fs::is_directory(GetDataDir(false))) {
 637         throw std::runtime_error(strprintf("specified data directory \"%s\" does not exist.", gArgs.GetArg("-datadir", "").c_str()));
 638     }
 639 }
 640
 641 #ifndef WIN32
 642 fs::path GetPidFile()
 643 {
 644     fs::path pathPidFile(gArgs.GetArg("-pid", BITCOIN_PID_FILENAME));
 645     if (!pathPidFile.is_complete()) pathPidFile = GetDataDir() / pathPidFile;
 646     return pathPidFile;
 647 }
 648
 649 void CreatePidFile(const fs::path &path, pid_t pid)
 650 {
 651     FILE* file = fsbridge::fopen(path, "w");
 652     if (file)
 653     {
 654         fprintf(file, "%d\n", pid);
 655         fclose(file);
 656     }
 657 }
 658 #endif
 659
 660 bool RenameOver(fs::path src, fs::path dest)
 661 {
 662 #ifdef WIN32
 663     return MoveFileExA(src.string().c_str(), dest.string().c_str(),
 664                        MOVEFILE_REPLACE_EXISTING) != 0;
 665 #else
 666     int rc = std::rename(src.string().c_str(), dest.string().c_str());
 667     return (rc == 0);
 668 #endif /* WIN32 */
 669 }
 670
 671 /**
 672  * Ignores exceptions thrown by Boost's create_directories if the requested directory exists.
 673  * Specifically handles case where path p exists, but it wasn't possible for the user to
 674  * write to the parent directory.
 675  */
 676 bool TryCreateDirectories(const fs::path& p)
 677 {
 678     try
 679     {
 680         return fs::create_directories(p);
 681     } catch (const fs::filesystem_error&) {
 682         if (!fs::exists(p) || !fs::is_directory(p))
 683             throw;
 684     }
 685
 686     // create_directories didn't create the directory, it had to have existed already
 687     return false;
 688 }
 689
 690 void FileCommit(FILE *file)
 691 {
 692     fflush(file); // harmless if redundantly called
 693 #ifdef WIN32
 694     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 695     FlushFileBuffers(hFile);
 696 #else
 697     #if defined(__linux__) || defined(__NetBSD__)
 698     fdatasync(fileno(file));
 699     #elif defined(__APPLE__) && defined(F_FULLFSYNC)
 700     fcntl(fileno(file), F_FULLFSYNC, 0);
 701     #else
 702     fsync(fileno(file));
 703     #endif
 704 #endif
 705 }
 706
 707 bool TruncateFile(FILE *file, unsigned int length) {
 708 #if defined(WIN32)
 709     return _chsize(_fileno(file), length) == 0;
 710 #else
 711     return ftruncate(fileno(file), length) == 0;
 712 #endif
 713 }
 714
 715 /**
 716  * this function tries to raise the file descriptor limit to the requested number.
 717  * It returns the actual file descriptor limit (which may be more or less than nMinFD)
 718  */
 719 int RaiseFileDescriptorLimit(int nMinFD) {
 720 #if defined(WIN32)
 721     return 2048;
 722 #else
 723     struct rlimit limitFD;
 724     if (getrlimit(RLIMIT_NOFILE, &limitFD) != -1) {
 725         if (limitFD.rlim_cur < (rlim_t)nMinFD) {
 726             limitFD.rlim_cur = nMinFD;
 727             if (limitFD.rlim_cur > limitFD.rlim_max)
 728                 limitFD.rlim_cur = limitFD.rlim_max;
 729             setrlimit(RLIMIT_NOFILE, &limitFD);
 730             getrlimit(RLIMIT_NOFILE, &limitFD);
 731         }
 732         return limitFD.rlim_cur;
 733     }
 734     return nMinFD; // getrlimit failed, assume it's fine
 735 #endif
 736 }
 737
 738 /**
 739  * this function tries to make a particular range of a file allocated (corresponding to disk space)
 740  * it is advisory, and the range specified in the arguments will never contain live data
 741  */
 742 void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length) {
 743 #if defined(WIN32)
 744     // Windows-specific version
 745     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 746     LARGE_INTEGER nFileSize;
 747     int64_t nEndPos = (int64_t)offset + length;
 748     nFileSize.u.LowPart = nEndPos & 0xFFFFFFFF;
 749     nFileSize.u.HighPart = nEndPos >> 32;
 750     SetFilePointerEx(hFile, nFileSize, 0, FILE_BEGIN);
 751     SetEndOfFile(hFile);
 752 #elif defined(MAC_OSX)
 753     // OSX specific version
 754     fstore_t fst;
 755     fst.fst_flags = F_ALLOCATECONTIG;
 756     fst.fst_posmode = F_PEOFPOSMODE;
 757     fst.fst_offset = 0;
 758     fst.fst_length = (off_t)offset + length;
 759     fst.fst_bytesalloc = 0;
 760     if (fcntl(fileno(file), F_PREALLOCATE, &fst) == -1) {
 761         fst.fst_flags = F_ALLOCATEALL;
 762         fcntl(fileno(file), F_PREALLOCATE, &fst);
 763     }
 764     ftruncate(fileno(file), fst.fst_length);
 765 #elif defined(__linux__)
 766     // Version using posix_fallocate
 767     off_t nEndPos = (off_t)offset + length;
 768     posix_fallocate(fileno(file), 0, nEndPos);
 769 #else
 770     // Fallback version
 771     // TODO: just write one byte per block
 772     static const char buf[65536] = {};
 773     fseek(file, offset, SEEK_SET);
 774     while (length > 0) {
 775         unsigned int now = 65536;
 776         if (length < now)
 777             now = length;
 778         fwrite(buf, 1, now, file); // allowed to fail; this function is advisory anyway
 779         length -= now;
 780     }
 781 #endif
 782 }
 783
 784 void ShrinkDebugFile()
 785 {
 786     // Amount of debug.log to save at end when shrinking (must fit in memory)
 787     constexpr size_t RECENT_DEBUG_HISTORY_SIZE = 10 * 1000000;
 788     // Scroll debug.log if it's getting too big
 789     fs::path pathLog = GetDebugLogPath();
 790     FILE* file = fsbridge::fopen(pathLog, "r");
 791     // If debug.log file is more than 10% bigger the RECENT_DEBUG_HISTORY_SIZE
 792     // trim it down by saving only the last RECENT_DEBUG_HISTORY_SIZE bytes
 793     if (file && fs::file_size(pathLog) > 11 * (RECENT_DEBUG_HISTORY_SIZE / 10))
 794     {
 795         // Restart the file with some of the end
 796         std::vector<char> vch(RECENT_DEBUG_HISTORY_SIZE, 0);
 797         fseek(file, -((long)vch.size()), SEEK_END);
 798         int nBytes = fread(vch.data(), 1, vch.size(), file);
 799         fclose(file);
 800
 801         file = fsbridge::fopen(pathLog, "w");
 802         if (file)
 803         {
 804             fwrite(vch.data(), 1, nBytes, file);
 805             fclose(file);
 806         }
 807     }
 808     else if (file != nullptr)
 809         fclose(file);
 810 }
 811
 812 #ifdef WIN32
 813 fs::path GetSpecialFolderPath(int nFolder, bool fCreate)
 814 {
 815     char pszPath[MAX_PATH] = "";
 816
 817     if(SHGetSpecialFolderPathA(nullptr, pszPath, nFolder, fCreate))
 818     {
 819         return fs::path(pszPath);
 820     }
 821
 822     LogPrintf("SHGetSpecialFolderPathA() failed, could not obtain requested path.\n");
 823     return fs::path("");
 824 }
 825 #endif
 826
 827 void runCommand(const std::string& strCommand)
 828 {
 829     if (strCommand.empty()) return;
 830     int nErr = ::system(strCommand.c_str());
 831     if (nErr)
 832         LogPrintf("runCommand error: system(%s) returned %d\n", strCommand, nErr);
 833 }
 834
 835 void RenameThread(const char* name)
 836 {
 837 #if defined(PR_SET_NAME)
 838     // Only the first 15 characters are used (16 - NUL terminator)
 839     ::prctl(PR_SET_NAME, name, 0, 0, 0);
 840 #elif (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
 841     pthread_set_name_np(pthread_self(), name);
 842
 843 #elif defined(MAC_OSX)
 844     pthread_setname_np(name);
 845 #else
 846     // Prevent warnings for unused parameters...
 847     (void)name;
 848 #endif
 849 }
 850
 851 void SetupEnvironment()
 852 {
 853 #ifdef HAVE_MALLOPT_ARENA_MAX
 854     // glibc-specific: On 32-bit systems set the number of arenas to 1.
 855     // By default, since glibc 2.10, the C library will create up to two heap
 856     // arenas per core. This is known to cause excessive virtual address space
 857     // usage in our usage. Work around it by setting the maximum number of
 858     // arenas to 1.
 859     if (sizeof(void*) == 4) {
 860         mallopt(M_ARENA_MAX, 1);
 861     }
 862 #endif
 863     // On most POSIX systems (e.g. Linux, but not BSD) the environment's locale
 864     // may be invalid, in which case the "C" locale is used as fallback.
 865 #if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
 866     try {
 867         std::locale(""); // Raises a runtime error if current locale is invalid
 868     } catch (const std::runtime_error&) {
 869         setenv("LC_ALL", "C", 1);
 870     }
 871 #endif
 872     // The path locale is lazy initialized and to avoid deinitialization errors
 873     // in multithreading environments, it is set explicitly by the main thread.
 874     // A dummy locale is used to extract the internal default locale, used by
 875     // fs::path, which is then used to explicitly imbue the path.
 876     std::locale loc = fs::path::imbue(std::locale::classic());
 877     fs::path::imbue(loc);
 878 }
 879
 880 bool SetupNetworking()
 881 {
 882 #ifdef WIN32
 883     // Initialize Windows Sockets
 884     WSADATA wsadata;
 885     int ret = WSAStartup(MAKEWORD(2,2), &wsadata);
 886     if (ret != NO_ERROR || LOBYTE(wsadata.wVersion ) != 2 || HIBYTE(wsadata.wVersion) != 2)
 887         return false;
 888 #endif
 889     return true;
 890 }
 891
 892 int GetNumCores()
 893 {
 894 #if BOOST_VERSION >= 105600
 895     return boost::thread::physical_concurrency();
 896 #else // Must fall back to hardware_concurrency, which unfortunately counts virtual cores
 897     return boost::thread::hardware_concurrency();
 898 #endif
 899 }
 900
 901 std::string CopyrightHolders(const std::string& strPrefix)
 902 {
 903     std::string strCopyrightHolders = strPrefix + strprintf(_(COPYRIGHT_HOLDERS), _(COPYRIGHT_HOLDERS_SUBSTITUTION));
 904
 905     // Check for untranslated substitution to make sure Bitcoin Core copyright is not removed by accident
 906     if (strprintf(COPYRIGHT_HOLDERS, COPYRIGHT_HOLDERS_SUBSTITUTION).find("Bitcoin Core") == std::string::npos) {
 907         strCopyrightHolders += "\n" + strPrefix + "The Bitcoin Core developers";
 908     }
 909     return strCopyrightHolders;
 910 }
 911
 912 // Obtain the application startup time (used for uptime calculation)
 913 int64_t GetStartupTime()
 914 {
 915     return nStartupTime;
 916 }