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