src/util.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 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 #if defined(HAVE_CONFIG_H)
   7 #include "config/bitcoin-config.h"
   8 #endif
   9
  10 #include "util.h"
  11
  12 #include "chainparamsbase.h"
  13 #include "fs.h"
  14 #include "random.h"
  15 #include "serialize.h"
  16 #include "utilstrencodings.h"
  17 #include "utiltime.h"
  18
  19 #include <stdarg.h>
  20
  21 #if (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
  22 #include <pthread.h>
  23 #include <pthread_np.h>
  24 #endif
  25
  26 #ifndef WIN32
  27 // for posix_fallocate
  28 #ifdef __linux__
  29
  30 #ifdef _POSIX_C_SOURCE
  31 #undef _POSIX_C_SOURCE
  32 #endif
  33
  34 #define _POSIX_C_SOURCE 200112L
  35
  36 #endif // __linux__
  37
  38 #include <algorithm>
  39 #include <fcntl.h>
  40 #include <sys/resource.h>
  41 #include <sys/stat.h>
  42
  43 #else
  44
  45 #ifdef _MSC_VER
  46 #pragma warning(disable:4786)
  47 #pragma warning(disable:4804)
  48 #pragma warning(disable:4805)
  49 #pragma warning(disable:4717)
  50 #endif
  51
  52 #ifdef _WIN32_WINNT
  53 #undef _WIN32_WINNT
  54 #endif
  55 #define _WIN32_WINNT 0x0501
  56
  57 #ifdef _WIN32_IE
  58 #undef _WIN32_IE
  59 #endif
  60 #define _WIN32_IE 0x0501
  61
  62 #define WIN32_LEAN_AND_MEAN 1
  63 #ifndef NOMINMAX
  64 #define NOMINMAX
  65 #endif
  66
  67 #include <io.h> /* for _commit */
  68 #include <shlobj.h>
  69 #endif
  70
  71 #ifdef HAVE_SYS_PRCTL_H
  72 #include <sys/prctl.h>
  73 #endif
  74
  75 #ifdef HAVE_MALLOPT_ARENA_MAX
  76 #include <malloc.h>
  77 #endif
  78
  79 #include <boost/algorithm/string/case_conv.hpp> // for to_lower()
  80 #include <boost/algorithm/string/join.hpp>
  81 #include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
  82 #include <boost/foreach.hpp>
  83 #include <boost/program_options/detail/config_file.hpp>
  84 #include <boost/program_options/parsers.hpp>
  85 #include <boost/thread.hpp>
  86 #include <openssl/crypto.h>
  87 #include <openssl/rand.h>
  88 #include <openssl/conf.h>
  89
  90
  91 const char * const BITCOIN_CONF_FILENAME = "bitcoin.conf";
  92 const char * const BITCOIN_PID_FILENAME = "bitcoind.pid";
  93
  94 ArgsManager gArgs;
  95 bool fPrintToConsole = false;
  96 bool fPrintToDebugLog = true;
  97
  98 bool fLogTimestamps = DEFAULT_LOGTIMESTAMPS;
  99 bool fLogTimeMicros = DEFAULT_LOGTIMEMICROS;
 100 bool fLogIPs = DEFAULT_LOGIPS;
 101 std::atomic<bool> fReopenDebugLog(false);
 102 CTranslationInterface translationInterface;
 103
 104 /** Log categories bitfield. */
 105 std::atomic<uint32_t> logCategories(0);
 106
 107 /** Init OpenSSL library multithreading support */
 108 static std::unique_ptr<CCriticalSection[]> ppmutexOpenSSL;
 109 void locking_callback(int mode, int i, const char* file, int line) NO_THREAD_SAFETY_ANALYSIS
 110 {
 111     if (mode & CRYPTO_LOCK) {
 112         ENTER_CRITICAL_SECTION(ppmutexOpenSSL[i]);
 113     } else {
 114         LEAVE_CRITICAL_SECTION(ppmutexOpenSSL[i]);
 115     }
 116 }
 117
 118 // Singleton for wrapping OpenSSL setup/teardown.
 119 class CInit
 120 {
 121 public:
 122     CInit()
 123     {
 124         // Init OpenSSL library multithreading support
 125         ppmutexOpenSSL.reset(new CCriticalSection[CRYPTO_num_locks()]);
 126         CRYPTO_set_locking_callback(locking_callback);
 127
 128         // OpenSSL can optionally load a config file which lists optional loadable modules and engines.
 129         // We don't use them so we don't require the config. However some of our libs may call functions
 130         // which attempt to load the config file, possibly resulting in an exit() or crash if it is missing
 131         // or corrupt. Explicitly tell OpenSSL not to try to load the file. The result for our libs will be
 132         // that the config appears to have been loaded and there are no modules/engines available.
 133         OPENSSL_no_config();
 134
 135 #ifdef WIN32
 136         // Seed OpenSSL PRNG with current contents of the screen
 137         RAND_screen();
 138 #endif
 139
 140         // Seed OpenSSL PRNG with performance counter
 141         RandAddSeed();
 142     }
 143     ~CInit()
 144     {
 145         // Securely erase the memory used by the PRNG
 146         RAND_cleanup();
 147         // Shutdown OpenSSL library multithreading support
 148         CRYPTO_set_locking_callback(NULL);
 149         // Clear the set of locks now to maintain symmetry with the constructor.
 150         ppmutexOpenSSL.reset();
 151     }
 152 }
 153 instance_of_cinit;
 154
 155 /**
 156  * LogPrintf() has been broken a couple of times now
 157  * by well-meaning people adding mutexes in the most straightforward way.
 158  * It breaks because it may be called by global destructors during shutdown.
 159  * Since the order of destruction of static/global objects is undefined,
 160  * defining a mutex as a global object doesn't work (the mutex gets
 161  * destroyed, and then some later destructor calls OutputDebugStringF,
 162  * maybe indirectly, and you get a core dump at shutdown trying to lock
 163  * the mutex).
 164  */
 165
 166 static boost::once_flag debugPrintInitFlag = BOOST_ONCE_INIT;
 167
 168 /**
 169  * We use boost::call_once() to make sure mutexDebugLog and
 170  * vMsgsBeforeOpenLog are initialized in a thread-safe manner.
 171  *
 172  * NOTE: fileout, mutexDebugLog and sometimes vMsgsBeforeOpenLog
 173  * are leaked on exit. This is ugly, but will be cleaned up by
 174  * the OS/libc. When the shutdown sequence is fully audited and
 175  * tested, explicit destruction of these objects can be implemented.
 176  */
 177 static FILE* fileout = NULL;
 178 static boost::mutex* mutexDebugLog = NULL;
 179 static std::list<std::string>* vMsgsBeforeOpenLog;
 180
 181 static int FileWriteStr(const std::string &str, FILE *fp)
 182 {
 183     return fwrite(str.data(), 1, str.size(), fp);
 184 }
 185
 186 static void DebugPrintInit()
 187 {
 188     assert(mutexDebugLog == NULL);
 189     mutexDebugLog = new boost::mutex();
 190     vMsgsBeforeOpenLog = new std::list<std::string>;
 191 }
 192
 193 void OpenDebugLog()
 194 {
 195     boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 196     boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 197
 198     assert(fileout == NULL);
 199     assert(vMsgsBeforeOpenLog);
 200     fs::path pathDebug = GetDataDir() / "debug.log";
 201     fileout = fsbridge::fopen(pathDebug, "a");
 202     if (fileout) {
 203         setbuf(fileout, NULL); // unbuffered
 204         // dump buffered messages from before we opened the log
 205         while (!vMsgsBeforeOpenLog->empty()) {
 206             FileWriteStr(vMsgsBeforeOpenLog->front(), fileout);
 207             vMsgsBeforeOpenLog->pop_front();
 208         }
 209     }
 210
 211     delete vMsgsBeforeOpenLog;
 212     vMsgsBeforeOpenLog = NULL;
 213 }
 214
 215 struct CLogCategoryDesc
 216 {
 217     uint32_t flag;
 218     std::string category;
 219 };
 220
 221 const CLogCategoryDesc LogCategories[] =
 222 {
 223     {BCLog::NONE, "0"},
 224     {BCLog::NET, "net"},
 225     {BCLog::TOR, "tor"},
 226     {BCLog::MEMPOOL, "mempool"},
 227     {BCLog::HTTP, "http"},
 228     {BCLog::BENCH, "bench"},
 229     {BCLog::ZMQ, "zmq"},
 230     {BCLog::DB, "db"},
 231     {BCLog::RPC, "rpc"},
 232     {BCLog::ESTIMATEFEE, "estimatefee"},
 233     {BCLog::ADDRMAN, "addrman"},
 234     {BCLog::SELECTCOINS, "selectcoins"},
 235     {BCLog::REINDEX, "reindex"},
 236     {BCLog::CMPCTBLOCK, "cmpctblock"},
 237     {BCLog::RAND, "rand"},
 238     {BCLog::PRUNE, "prune"},
 239     {BCLog::PROXY, "proxy"},
 240     {BCLog::MEMPOOLREJ, "mempoolrej"},
 241     {BCLog::LIBEVENT, "libevent"},
 242     {BCLog::COINDB, "coindb"},
 243     {BCLog::QT, "qt"},
 244     {BCLog::LEVELDB, "leveldb"},
 245     {BCLog::ALL, "1"},
 246     {BCLog::ALL, "all"},
 247 };
 248
 249 bool GetLogCategory(uint32_t *f, const std::string *str)
 250 {
 251     if (f && str) {
 252         if (*str == "") {
 253             *f = BCLog::ALL;
 254             return true;
 255         }
 256         for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 257             if (LogCategories[i].category == *str) {
 258                 *f = LogCategories[i].flag;
 259                 return true;
 260             }
 261         }
 262     }
 263     return false;
 264 }
 265
 266 std::string ListLogCategories()
 267 {
 268     std::string ret;
 269     int outcount = 0;
 270     for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 271         // Omit the special cases.
 272         if (LogCategories[i].flag != BCLog::NONE && LogCategories[i].flag != BCLog::ALL) {
 273             if (outcount != 0) ret += ", ";
 274             ret += LogCategories[i].category;
 275             outcount++;
 276         }
 277     }
 278     return ret;
 279 }
 280
 281 std::vector<CLogCategoryActive> ListActiveLogCategories()
 282 {
 283     std::vector<CLogCategoryActive> ret;
 284     for (unsigned int i = 0; i < ARRAYLEN(LogCategories); i++) {
 285         // Omit the special cases.
 286         if (LogCategories[i].flag != BCLog::NONE && LogCategories[i].flag != BCLog::ALL) {
 287             CLogCategoryActive catActive;
 288             catActive.category = LogCategories[i].category;
 289             catActive.active = LogAcceptCategory(LogCategories[i].flag);
 290             ret.push_back(catActive);
 291         }
 292     }
 293     return ret;
 294 }
 295
 296 /**
 297  * fStartedNewLine is a state variable held by the calling context that will
 298  * suppress printing of the timestamp when multiple calls are made that don't
 299  * end in a newline. Initialize it to true, and hold it, in the calling context.
 300  */
 301 static std::string LogTimestampStr(const std::string &str, std::atomic_bool *fStartedNewLine)
 302 {
 303     std::string strStamped;
 304
 305     if (!fLogTimestamps)
 306         return str;
 307
 308     if (*fStartedNewLine) {
 309         int64_t nTimeMicros = GetTimeMicros();
 310         strStamped = DateTimeStrFormat("%Y-%m-%d %H:%M:%S", nTimeMicros/1000000);
 311         if (fLogTimeMicros)
 312             strStamped += strprintf(".%06d", nTimeMicros%1000000);
 313         int64_t mocktime = GetMockTime();
 314         if (mocktime) {
 315             strStamped += " (mocktime: " + DateTimeStrFormat("%Y-%m-%d %H:%M:%S", mocktime) + ")";
 316         }
 317         strStamped += ' ' + str;
 318     } else
 319         strStamped = str;
 320
 321     if (!str.empty() && str[str.size()-1] == '\n')
 322         *fStartedNewLine = true;
 323     else
 324         *fStartedNewLine = false;
 325
 326     return strStamped;
 327 }
 328
 329 int LogPrintStr(const std::string &str)
 330 {
 331     int ret = 0; // Returns total number of characters written
 332     static std::atomic_bool fStartedNewLine(true);
 333
 334     std::string strTimestamped = LogTimestampStr(str, &fStartedNewLine);
 335
 336     if (fPrintToConsole)
 337     {
 338         // print to console
 339         ret = fwrite(strTimestamped.data(), 1, strTimestamped.size(), stdout);
 340         fflush(stdout);
 341     }
 342     else if (fPrintToDebugLog)
 343     {
 344         boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 345         boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 346
 347         // buffer if we haven't opened the log yet
 348         if (fileout == NULL) {
 349             assert(vMsgsBeforeOpenLog);
 350             ret = strTimestamped.length();
 351             vMsgsBeforeOpenLog->push_back(strTimestamped);
 352         }
 353         else
 354         {
 355             // reopen the log file, if requested
 356             if (fReopenDebugLog) {
 357                 fReopenDebugLog = false;
 358                 fs::path pathDebug = GetDataDir() / "debug.log";
 359                 if (fsbridge::freopen(pathDebug,"a",fileout) != NULL)
 360                     setbuf(fileout, NULL); // unbuffered
 361             }
 362
 363             ret = FileWriteStr(strTimestamped, fileout);
 364         }
 365     }
 366     return ret;
 367 }
 368
 369 /** Interpret string as boolean, for argument parsing */
 370 static bool InterpretBool(const std::string& strValue)
 371 {
 372     if (strValue.empty())
 373         return true;
 374     return (atoi(strValue) != 0);
 375 }
 376
 377 /** Turn -noX into -X=0 */
 378 static void InterpretNegativeSetting(std::string& strKey, std::string& strValue)
 379 {
 380     if (strKey.length()>3 && strKey[0]=='-' && strKey[1]=='n' && strKey[2]=='o')
 381     {
 382         strKey = "-" + strKey.substr(3);
 383         strValue = InterpretBool(strValue) ? "0" : "1";
 384     }
 385 }
 386
 387 void ArgsManager::ParseParameters(int argc, const char* const argv[])
 388 {
 389     LOCK(cs_args);
 390     mapArgs.clear();
 391     mapMultiArgs.clear();
 392
 393     for (int i = 1; i < argc; i++)
 394     {
 395         std::string str(argv[i]);
 396         std::string strValue;
 397         size_t is_index = str.find('=');
 398         if (is_index != std::string::npos)
 399         {
 400             strValue = str.substr(is_index+1);
 401             str = str.substr(0, is_index);
 402         }
 403 #ifdef WIN32
 404         boost::to_lower(str);
 405         if (boost::algorithm::starts_with(str, "/"))
 406             str = "-" + str.substr(1);
 407 #endif
 408
 409         if (str[0] != '-')
 410             break;
 411
 412         // Interpret --foo as -foo.
 413         // If both --foo and -foo are set, the last takes effect.
 414         if (str.length() > 1 && str[1] == '-')
 415             str = str.substr(1);
 416         InterpretNegativeSetting(str, strValue);
 417
 418         mapArgs[str] = strValue;
 419         mapMultiArgs[str].push_back(strValue);
 420     }
 421 }
 422
 423 std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg)
 424 {
 425     LOCK(cs_args);
 426     return mapMultiArgs.at(strArg);
 427 }
 428
 429 bool ArgsManager::IsArgSet(const std::string& strArg)
 430 {
 431     LOCK(cs_args);
 432     return mapArgs.count(strArg);
 433 }
 434
 435 std::string ArgsManager::GetArg(const std::string& strArg, const std::string& strDefault)
 436 {
 437     LOCK(cs_args);
 438     if (mapArgs.count(strArg))
 439         return mapArgs[strArg];
 440     return strDefault;
 441 }
 442
 443 int64_t ArgsManager::GetArg(const std::string& strArg, int64_t nDefault)
 444 {
 445     LOCK(cs_args);
 446     if (mapArgs.count(strArg))
 447         return atoi64(mapArgs[strArg]);
 448     return nDefault;
 449 }
 450
 451 bool ArgsManager::GetBoolArg(const std::string& strArg, bool fDefault)
 452 {
 453     LOCK(cs_args);
 454     if (mapArgs.count(strArg))
 455         return InterpretBool(mapArgs[strArg]);
 456     return fDefault;
 457 }
 458
 459 bool ArgsManager::SoftSetArg(const std::string& strArg, const std::string& strValue)
 460 {
 461     LOCK(cs_args);
 462     if (mapArgs.count(strArg))
 463         return false;
 464     ForceSetArg(strArg, strValue);
 465     return true;
 466 }
 467
 468 bool ArgsManager::SoftSetBoolArg(const std::string& strArg, bool fValue)
 469 {
 470     if (fValue)
 471         return SoftSetArg(strArg, std::string("1"));
 472     else
 473         return SoftSetArg(strArg, std::string("0"));
 474 }
 475
 476 void ArgsManager::ForceSetArg(const std::string& strArg, const std::string& strValue)
 477 {
 478     LOCK(cs_args);
 479     mapArgs[strArg] = strValue;
 480     mapMultiArgs[strArg].push_back(strValue);
 481 }
 482
 483
 484
 485 static const int screenWidth = 79;
 486 static const int optIndent = 2;
 487 static const int msgIndent = 7;
 488
 489 std::string HelpMessageGroup(const std::string &message) {
 490     return std::string(message) + std::string("\n\n");
 491 }
 492
 493 std::string HelpMessageOpt(const std::string &option, const std::string &message) {
 494     return std::string(optIndent,' ') + std::string(option) +
 495            std::string("\n") + std::string(msgIndent,' ') +
 496            FormatParagraph(message, screenWidth - msgIndent, msgIndent) +
 497            std::string("\n\n");
 498 }
 499
 500 static std::string FormatException(const std::exception* pex, const char* pszThread)
 501 {
 502 #ifdef WIN32
 503     char pszModule[MAX_PATH] = "";
 504     GetModuleFileNameA(NULL, pszModule, sizeof(pszModule));
 505 #else
 506     const char* pszModule = "bitcoin";
 507 #endif
 508     if (pex)
 509         return strprintf(
 510             "EXCEPTION: %s       \n%s       \n%s in %s       \n", typeid(*pex).name(), pex->what(), pszModule, pszThread);
 511     else
 512         return strprintf(
 513             "UNKNOWN EXCEPTION       \n%s in %s       \n", pszModule, pszThread);
 514 }
 515
 516 void PrintExceptionContinue(const std::exception* pex, const char* pszThread)
 517 {
 518     std::string message = FormatException(pex, pszThread);
 519     LogPrintf("\n\n************************\n%s\n", message);
 520     fprintf(stderr, "\n\n************************\n%s\n", message.c_str());
 521 }
 522
 523 fs::path GetDefaultDataDir()
 524 {
 525     // Windows < Vista: C:\Documents and Settings\Username\Application Data\Bitcoin
 526     // Windows >= Vista: C:\Users\Username\AppData\Roaming\Bitcoin
 527     // Mac: ~/Library/Application Support/Bitcoin
 528     // Unix: ~/.bitcoin
 529 #ifdef WIN32
 530     // Windows
 531     return GetSpecialFolderPath(CSIDL_APPDATA) / "Bitcoin";
 532 #else
 533     fs::path pathRet;
 534     char* pszHome = getenv("HOME");
 535     if (pszHome == NULL || strlen(pszHome) == 0)
 536         pathRet = fs::path("/");
 537     else
 538         pathRet = fs::path(pszHome);
 539 #ifdef MAC_OSX
 540     // Mac
 541     return pathRet / "Library/Application Support/Bitcoin";
 542 #else
 543     // Unix
 544     return pathRet / ".bitcoin";
 545 #endif
 546 #endif
 547 }
 548
 549 static fs::path pathCached;
 550 static fs::path pathCachedNetSpecific;
 551 static CCriticalSection csPathCached;
 552
 553 const fs::path &GetDataDir(bool fNetSpecific)
 554 {
 555
 556     LOCK(csPathCached);
 557
 558     fs::path &path = fNetSpecific ? pathCachedNetSpecific : pathCached;
 559
 560     // This can be called during exceptions by LogPrintf(), so we cache the
 561     // value so we don't have to do memory allocations after that.
 562     if (!path.empty())
 563         return path;
 564
 565     if (IsArgSet("-datadir")) {
 566         path = fs::system_complete(GetArg("-datadir", ""));
 567         if (!fs::is_directory(path)) {
 568             path = "";
 569             return path;
 570         }
 571     } else {
 572         path = GetDefaultDataDir();
 573     }
 574     if (fNetSpecific)
 575         path /= BaseParams().DataDir();
 576
 577     fs::create_directories(path);
 578
 579     return path;
 580 }
 581
 582 void ClearDatadirCache()
 583 {
 584     LOCK(csPathCached);
 585
 586     pathCached = fs::path();
 587     pathCachedNetSpecific = fs::path();
 588 }
 589
 590 fs::path GetConfigFile(const std::string& confPath)
 591 {
 592     fs::path pathConfigFile(confPath);
 593     if (!pathConfigFile.is_complete())
 594         pathConfigFile = GetDataDir(false) / pathConfigFile;
 595
 596     return pathConfigFile;
 597 }
 598
 599 void ArgsManager::ReadConfigFile(const std::string& confPath)
 600 {
 601     fs::ifstream streamConfig(GetConfigFile(confPath));
 602     if (!streamConfig.good())
 603         return; // No bitcoin.conf file is OK
 604
 605     {
 606         LOCK(cs_args);
 607         std::set<std::string> setOptions;
 608         setOptions.insert("*");
 609
 610         for (boost::program_options::detail::config_file_iterator it(streamConfig, setOptions), end; it != end; ++it)
 611         {
 612             // Don't overwrite existing settings so command line settings override bitcoin.conf
 613             std::string strKey = std::string("-") + it->string_key;
 614             std::string strValue = it->value[0];
 615             InterpretNegativeSetting(strKey, strValue);
 616             if (mapArgs.count(strKey) == 0)
 617                 mapArgs[strKey] = strValue;
 618             mapMultiArgs[strKey].push_back(strValue);
 619         }
 620     }
 621     // If datadir is changed in .conf file:
 622     ClearDatadirCache();
 623 }
 624
 625 #ifndef WIN32
 626 fs::path GetPidFile()
 627 {
 628     fs::path pathPidFile(GetArg("-pid", BITCOIN_PID_FILENAME));
 629     if (!pathPidFile.is_complete()) pathPidFile = GetDataDir() / pathPidFile;
 630     return pathPidFile;
 631 }
 632
 633 void CreatePidFile(const fs::path &path, pid_t pid)
 634 {
 635     FILE* file = fsbridge::fopen(path, "w");
 636     if (file)
 637     {
 638         fprintf(file, "%d\n", pid);
 639         fclose(file);
 640     }
 641 }
 642 #endif
 643
 644 bool RenameOver(fs::path src, fs::path dest)
 645 {
 646 #ifdef WIN32
 647     return MoveFileExA(src.string().c_str(), dest.string().c_str(),
 648                        MOVEFILE_REPLACE_EXISTING) != 0;
 649 #else
 650     int rc = std::rename(src.string().c_str(), dest.string().c_str());
 651     return (rc == 0);
 652 #endif /* WIN32 */
 653 }
 654
 655 /**
 656  * Ignores exceptions thrown by Boost's create_directory if the requested directory exists.
 657  * Specifically handles case where path p exists, but it wasn't possible for the user to
 658  * write to the parent directory.
 659  */
 660 bool TryCreateDirectory(const fs::path& p)
 661 {
 662     try
 663     {
 664         return fs::create_directory(p);
 665     } catch (const fs::filesystem_error&) {
 666         if (!fs::exists(p) || !fs::is_directory(p))
 667             throw;
 668     }
 669
 670     // create_directory didn't create the directory, it had to have existed already
 671     return false;
 672 }
 673
 674 void FileCommit(FILE *file)
 675 {
 676     fflush(file); // harmless if redundantly called
 677 #ifdef WIN32
 678     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 679     FlushFileBuffers(hFile);
 680 #else
 681     #if defined(__linux__) || defined(__NetBSD__)
 682     fdatasync(fileno(file));
 683     #elif defined(__APPLE__) && defined(F_FULLFSYNC)
 684     fcntl(fileno(file), F_FULLFSYNC, 0);
 685     #else
 686     fsync(fileno(file));
 687     #endif
 688 #endif
 689 }
 690
 691 bool TruncateFile(FILE *file, unsigned int length) {
 692 #if defined(WIN32)
 693     return _chsize(_fileno(file), length) == 0;
 694 #else
 695     return ftruncate(fileno(file), length) == 0;
 696 #endif
 697 }
 698
 699 /**
 700  * this function tries to raise the file descriptor limit to the requested number.
 701  * It returns the actual file descriptor limit (which may be more or less than nMinFD)
 702  */
 703 int RaiseFileDescriptorLimit(int nMinFD) {
 704 #if defined(WIN32)
 705     return 2048;
 706 #else
 707     struct rlimit limitFD;
 708     if (getrlimit(RLIMIT_NOFILE, &limitFD) != -1) {
 709         if (limitFD.rlim_cur < (rlim_t)nMinFD) {
 710             limitFD.rlim_cur = nMinFD;
 711             if (limitFD.rlim_cur > limitFD.rlim_max)
 712                 limitFD.rlim_cur = limitFD.rlim_max;
 713             setrlimit(RLIMIT_NOFILE, &limitFD);
 714             getrlimit(RLIMIT_NOFILE, &limitFD);
 715         }
 716         return limitFD.rlim_cur;
 717     }
 718     return nMinFD; // getrlimit failed, assume it's fine
 719 #endif
 720 }
 721
 722 /**
 723  * this function tries to make a particular range of a file allocated (corresponding to disk space)
 724  * it is advisory, and the range specified in the arguments will never contain live data
 725  */
 726 void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length) {
 727 #if defined(WIN32)
 728     // Windows-specific version
 729     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 730     LARGE_INTEGER nFileSize;
 731     int64_t nEndPos = (int64_t)offset + length;
 732     nFileSize.u.LowPart = nEndPos & 0xFFFFFFFF;
 733     nFileSize.u.HighPart = nEndPos >> 32;
 734     SetFilePointerEx(hFile, nFileSize, 0, FILE_BEGIN);
 735     SetEndOfFile(hFile);
 736 #elif defined(MAC_OSX)
 737     // OSX specific version
 738     fstore_t fst;
 739     fst.fst_flags = F_ALLOCATECONTIG;
 740     fst.fst_posmode = F_PEOFPOSMODE;
 741     fst.fst_offset = 0;
 742     fst.fst_length = (off_t)offset + length;
 743     fst.fst_bytesalloc = 0;
 744     if (fcntl(fileno(file), F_PREALLOCATE, &fst) == -1) {
 745         fst.fst_flags = F_ALLOCATEALL;
 746         fcntl(fileno(file), F_PREALLOCATE, &fst);
 747     }
 748     ftruncate(fileno(file), fst.fst_length);
 749 #elif defined(__linux__)
 750     // Version using posix_fallocate
 751     off_t nEndPos = (off_t)offset + length;
 752     posix_fallocate(fileno(file), 0, nEndPos);
 753 #else
 754     // Fallback version
 755     // TODO: just write one byte per block
 756     static const char buf[65536] = {};
 757     fseek(file, offset, SEEK_SET);
 758     while (length > 0) {
 759         unsigned int now = 65536;
 760         if (length < now)
 761             now = length;
 762         fwrite(buf, 1, now, file); // allowed to fail; this function is advisory anyway
 763         length -= now;
 764     }
 765 #endif
 766 }
 767
 768 void ShrinkDebugFile()
 769 {
 770     // Amount of debug.log to save at end when shrinking (must fit in memory)
 771     constexpr size_t RECENT_DEBUG_HISTORY_SIZE = 10 * 1000000;
 772     // Scroll debug.log if it's getting too big
 773     fs::path pathLog = GetDataDir() / "debug.log";
 774     FILE* file = fsbridge::fopen(pathLog, "r");
 775     // If debug.log file is more than 10% bigger the RECENT_DEBUG_HISTORY_SIZE
 776     // trim it down by saving only the last RECENT_DEBUG_HISTORY_SIZE bytes
 777     if (file && fs::file_size(pathLog) > 11 * (RECENT_DEBUG_HISTORY_SIZE / 10))
 778     {
 779         // Restart the file with some of the end
 780         std::vector<char> vch(RECENT_DEBUG_HISTORY_SIZE, 0);
 781         fseek(file, -((long)vch.size()), SEEK_END);
 782         int nBytes = fread(vch.data(), 1, vch.size(), file);
 783         fclose(file);
 784
 785         file = fsbridge::fopen(pathLog, "w");
 786         if (file)
 787         {
 788             fwrite(vch.data(), 1, nBytes, file);
 789             fclose(file);
 790         }
 791     }
 792     else if (file != NULL)
 793         fclose(file);
 794 }
 795
 796 #ifdef WIN32
 797 fs::path GetSpecialFolderPath(int nFolder, bool fCreate)
 798 {
 799     char pszPath[MAX_PATH] = "";
 800
 801     if(SHGetSpecialFolderPathA(NULL, pszPath, nFolder, fCreate))
 802     {
 803         return fs::path(pszPath);
 804     }
 805
 806     LogPrintf("SHGetSpecialFolderPathA() failed, could not obtain requested path.\n");
 807     return fs::path("");
 808 }
 809 #endif
 810
 811 void runCommand(const std::string& strCommand)
 812 {
 813     int nErr = ::system(strCommand.c_str());
 814     if (nErr)
 815         LogPrintf("runCommand error: system(%s) returned %d\n", strCommand, nErr);
 816 }
 817
 818 void RenameThread(const char* name)
 819 {
 820 #if defined(PR_SET_NAME)
 821     // Only the first 15 characters are used (16 - NUL terminator)
 822     ::prctl(PR_SET_NAME, name, 0, 0, 0);
 823 #elif (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
 824     pthread_set_name_np(pthread_self(), name);
 825
 826 #elif defined(MAC_OSX)
 827     pthread_setname_np(name);
 828 #else
 829     // Prevent warnings for unused parameters...
 830     (void)name;
 831 #endif
 832 }
 833
 834 void SetupEnvironment()
 835 {
 836 #ifdef HAVE_MALLOPT_ARENA_MAX
 837     // glibc-specific: On 32-bit systems set the number of arenas to 1.
 838     // By default, since glibc 2.10, the C library will create up to two heap
 839     // arenas per core. This is known to cause excessive virtual address space
 840     // usage in our usage. Work around it by setting the maximum number of
 841     // arenas to 1.
 842     if (sizeof(void*) == 4) {
 843         mallopt(M_ARENA_MAX, 1);
 844     }
 845 #endif
 846     // On most POSIX systems (e.g. Linux, but not BSD) the environment's locale
 847     // may be invalid, in which case the "C" locale is used as fallback.
 848 #if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
 849     try {
 850         std::locale(""); // Raises a runtime error if current locale is invalid
 851     } catch (const std::runtime_error&) {
 852         setenv("LC_ALL", "C", 1);
 853     }
 854 #endif
 855     // The path locale is lazy initialized and to avoid deinitialization errors
 856     // in multithreading environments, it is set explicitly by the main thread.
 857     // A dummy locale is used to extract the internal default locale, used by
 858     // fs::path, which is then used to explicitly imbue the path.
 859     std::locale loc = fs::path::imbue(std::locale::classic());
 860     fs::path::imbue(loc);
 861 }
 862
 863 bool SetupNetworking()
 864 {
 865 #ifdef WIN32
 866     // Initialize Windows Sockets
 867     WSADATA wsadata;
 868     int ret = WSAStartup(MAKEWORD(2,2), &wsadata);
 869     if (ret != NO_ERROR || LOBYTE(wsadata.wVersion ) != 2 || HIBYTE(wsadata.wVersion) != 2)
 870         return false;
 871 #endif
 872     return true;
 873 }
 874
 875 int GetNumCores()
 876 {
 877 #if BOOST_VERSION >= 105600
 878     return boost::thread::physical_concurrency();
 879 #else // Must fall back to hardware_concurrency, which unfortunately counts virtual cores
 880     return boost::thread::hardware_concurrency();
 881 #endif
 882 }
 883
 884 std::string CopyrightHolders(const std::string& strPrefix)
 885 {
 886     std::string strCopyrightHolders = strPrefix + strprintf(_(COPYRIGHT_HOLDERS), _(COPYRIGHT_HOLDERS_SUBSTITUTION));
 887
 888     // Check for untranslated substitution to make sure Bitcoin Core copyright is not removed by accident
 889     if (strprintf(COPYRIGHT_HOLDERS, COPYRIGHT_HOLDERS_SUBSTITUTION).find("Bitcoin Core") == std::string::npos) {
 890         strCopyrightHolders += "\n" + strPrefix + "The Bitcoin Core developers";
 891     }
 892     return strCopyrightHolders;
 893 }