src/util.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2015 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 "random.h"
  14 #include "serialize.h"
  15 #include "sync.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 #include <boost/algorithm/string/case_conv.hpp> // for to_lower()
  76 #include <boost/algorithm/string/join.hpp>
  77 #include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
  78 #include <boost/filesystem.hpp>
  79 #include <boost/filesystem/fstream.hpp>
  80 #include <boost/foreach.hpp>
  81 #include <boost/program_options/detail/config_file.hpp>
  82 #include <boost/program_options/parsers.hpp>
  83 #include <boost/thread.hpp>
  84 #include <openssl/crypto.h>
  85 #include <openssl/rand.h>
  86 #include <openssl/conf.h>
  87
  88 // Work around clang compilation problem in Boost 1.46:
  89 // /usr/include/boost/program_options/detail/config_file.hpp:163:17: error: call to function 'to_internal' that is neither visible in the template definition nor found by argument-dependent lookup
  90 // See also: http://stackoverflow.com/questions/10020179/compilation-fail-in-boost-librairies-program-options
  91 //           http://clang.debian.net/status.php?version=3.0&key=CANNOT_FIND_FUNCTION
  92 namespace boost {
  93
  94     namespace program_options {
  95         std::string to_internal(const std::string&);
  96     }
  97
  98 } // namespace boost
  99
 100 using namespace std;
 101
 102 const char * const BITCOIN_CONF_FILENAME = "bitcoin.conf";
 103 const char * const BITCOIN_PID_FILENAME = "bitcoind.pid";
 104
 105 map<string, string> mapArgs;
 106 map<string, vector<string> > mapMultiArgs;
 107 bool fDebug = false;
 108 bool fPrintToConsole = false;
 109 bool fPrintToDebugLog = true;
 110 string strMiscWarning;
 111 bool fLogTimestamps = DEFAULT_LOGTIMESTAMPS;
 112 bool fLogTimeMicros = DEFAULT_LOGTIMEMICROS;
 113 bool fLogIPs = DEFAULT_LOGIPS;
 114 std::atomic<bool> fReopenDebugLog(false);
 115 CTranslationInterface translationInterface;
 116
 117 /** Init OpenSSL library multithreading support */
 118 static CCriticalSection** ppmutexOpenSSL;
 119 void locking_callback(int mode, int i, const char* file, int line) NO_THREAD_SAFETY_ANALYSIS
 120 {
 121     if (mode & CRYPTO_LOCK) {
 122         ENTER_CRITICAL_SECTION(*ppmutexOpenSSL[i]);
 123     } else {
 124         LEAVE_CRITICAL_SECTION(*ppmutexOpenSSL[i]);
 125     }
 126 }
 127
 128 // Init
 129 class CInit
 130 {
 131 public:
 132     CInit()
 133     {
 134         // Init OpenSSL library multithreading support
 135         ppmutexOpenSSL = (CCriticalSection**)OPENSSL_malloc(CRYPTO_num_locks() * sizeof(CCriticalSection*));
 136         for (int i = 0; i < CRYPTO_num_locks(); i++)
 137             ppmutexOpenSSL[i] = new CCriticalSection();
 138         CRYPTO_set_locking_callback(locking_callback);
 139
 140         // OpenSSL can optionally load a config file which lists optional loadable modules and engines.
 141         // We don't use them so we don't require the config. However some of our libs may call functions
 142         // which attempt to load the config file, possibly resulting in an exit() or crash if it is missing
 143         // or corrupt. Explicitly tell OpenSSL not to try to load the file. The result for our libs will be
 144         // that the config appears to have been loaded and there are no modules/engines available.
 145         OPENSSL_no_config();
 146
 147 #ifdef WIN32
 148         // Seed OpenSSL PRNG with current contents of the screen
 149         RAND_screen();
 150 #endif
 151
 152         // Seed OpenSSL PRNG with performance counter
 153         RandAddSeed();
 154     }
 155     ~CInit()
 156     {
 157         // Securely erase the memory used by the PRNG
 158         RAND_cleanup();
 159         // Shutdown OpenSSL library multithreading support
 160         CRYPTO_set_locking_callback(NULL);
 161         for (int i = 0; i < CRYPTO_num_locks(); i++)
 162             delete ppmutexOpenSSL[i];
 163         OPENSSL_free(ppmutexOpenSSL);
 164     }
 165 }
 166 instance_of_cinit;
 167
 168 /**
 169  * LogPrintf() has been broken a couple of times now
 170  * by well-meaning people adding mutexes in the most straightforward way.
 171  * It breaks because it may be called by global destructors during shutdown.
 172  * Since the order of destruction of static/global objects is undefined,
 173  * defining a mutex as a global object doesn't work (the mutex gets
 174  * destroyed, and then some later destructor calls OutputDebugStringF,
 175  * maybe indirectly, and you get a core dump at shutdown trying to lock
 176  * the mutex).
 177  */
 178
 179 static boost::once_flag debugPrintInitFlag = BOOST_ONCE_INIT;
 180
 181 /**
 182  * We use boost::call_once() to make sure mutexDebugLog and
 183  * vMsgsBeforeOpenLog are initialized in a thread-safe manner.
 184  *
 185  * NOTE: fileout, mutexDebugLog and sometimes vMsgsBeforeOpenLog
 186  * are leaked on exit. This is ugly, but will be cleaned up by
 187  * the OS/libc. When the shutdown sequence is fully audited and
 188  * tested, explicit destruction of these objects can be implemented.
 189  */
 190 static FILE* fileout = NULL;
 191 static boost::mutex* mutexDebugLog = NULL;
 192 static list<string> *vMsgsBeforeOpenLog;
 193
 194 static int FileWriteStr(const std::string &str, FILE *fp)
 195 {
 196     return fwrite(str.data(), 1, str.size(), fp);
 197 }
 198
 199 static void DebugPrintInit()
 200 {
 201     assert(mutexDebugLog == NULL);
 202     mutexDebugLog = new boost::mutex();
 203     vMsgsBeforeOpenLog = new list<string>;
 204 }
 205
 206 void OpenDebugLog()
 207 {
 208     boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 209     boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 210
 211     assert(fileout == NULL);
 212     assert(vMsgsBeforeOpenLog);
 213     boost::filesystem::path pathDebug = GetDataDir() / "debug.log";
 214     fileout = fopen(pathDebug.string().c_str(), "a");
 215     if (fileout) setbuf(fileout, NULL); // unbuffered
 216
 217     // dump buffered messages from before we opened the log
 218     while (!vMsgsBeforeOpenLog->empty()) {
 219         FileWriteStr(vMsgsBeforeOpenLog->front(), fileout);
 220         vMsgsBeforeOpenLog->pop_front();
 221     }
 222
 223     delete vMsgsBeforeOpenLog;
 224     vMsgsBeforeOpenLog = NULL;
 225 }
 226
 227 bool LogAcceptCategory(const char* category)
 228 {
 229     if (category != NULL)
 230     {
 231         if (!fDebug)
 232             return false;
 233
 234         // Give each thread quick access to -debug settings.
 235         // This helps prevent issues debugging global destructors,
 236         // where mapMultiArgs might be deleted before another
 237         // global destructor calls LogPrint()
 238         static boost::thread_specific_ptr<set<string> > ptrCategory;
 239         if (ptrCategory.get() == NULL)
 240         {
 241             const vector<string>& categories = mapMultiArgs["-debug"];
 242             ptrCategory.reset(new set<string>(categories.begin(), categories.end()));
 243             // thread_specific_ptr automatically deletes the set when the thread ends.
 244         }
 245         const set<string>& setCategories = *ptrCategory.get();
 246
 247         // if not debugging everything and not debugging specific category, LogPrint does nothing.
 248         if (setCategories.count(string("")) == 0 &&
 249             setCategories.count(string("1")) == 0 &&
 250             setCategories.count(string(category)) == 0)
 251             return false;
 252     }
 253     return true;
 254 }
 255
 256 /**
 257  * fStartedNewLine is a state variable held by the calling context that will
 258  * suppress printing of the timestamp when multiple calls are made that don't
 259  * end in a newline. Initialize it to true, and hold it, in the calling context.
 260  */
 261 static std::string LogTimestampStr(const std::string &str, bool *fStartedNewLine)
 262 {
 263     string strStamped;
 264
 265     if (!fLogTimestamps)
 266         return str;
 267
 268     if (*fStartedNewLine) {
 269         int64_t nTimeMicros = GetLogTimeMicros();
 270         strStamped = DateTimeStrFormat("%Y-%m-%d %H:%M:%S", nTimeMicros/1000000);
 271         if (fLogTimeMicros)
 272             strStamped += strprintf(".%06d", nTimeMicros%1000000);
 273         strStamped += ' ' + str;
 274     } else
 275         strStamped = str;
 276
 277     if (!str.empty() && str[str.size()-1] == '\n')
 278         *fStartedNewLine = true;
 279     else
 280         *fStartedNewLine = false;
 281
 282     return strStamped;
 283 }
 284
 285 int LogPrintStr(const std::string &str)
 286 {
 287     int ret = 0; // Returns total number of characters written
 288     static bool fStartedNewLine = true;
 289
 290     string strTimestamped = LogTimestampStr(str, &fStartedNewLine);
 291
 292     if (fPrintToConsole)
 293     {
 294         // print to console
 295         ret = fwrite(strTimestamped.data(), 1, strTimestamped.size(), stdout);
 296         fflush(stdout);
 297     }
 298     else if (fPrintToDebugLog)
 299     {
 300         boost::call_once(&DebugPrintInit, debugPrintInitFlag);
 301         boost::mutex::scoped_lock scoped_lock(*mutexDebugLog);
 302
 303         // buffer if we haven't opened the log yet
 304         if (fileout == NULL) {
 305             assert(vMsgsBeforeOpenLog);
 306             ret = strTimestamped.length();
 307             vMsgsBeforeOpenLog->push_back(strTimestamped);
 308         }
 309         else
 310         {
 311             // reopen the log file, if requested
 312             if (fReopenDebugLog) {
 313                 fReopenDebugLog = false;
 314                 boost::filesystem::path pathDebug = GetDataDir() / "debug.log";
 315                 if (freopen(pathDebug.string().c_str(),"a",fileout) != NULL)
 316                     setbuf(fileout, NULL); // unbuffered
 317             }
 318
 319             ret = FileWriteStr(strTimestamped, fileout);
 320         }
 321     }
 322     return ret;
 323 }
 324
 325 /** Interpret string as boolean, for argument parsing */
 326 static bool InterpretBool(const std::string& strValue)
 327 {
 328     if (strValue.empty())
 329         return true;
 330     return (atoi(strValue) != 0);
 331 }
 332
 333 /** Turn -noX into -X=0 */
 334 static void InterpretNegativeSetting(std::string& strKey, std::string& strValue)
 335 {
 336     if (strKey.length()>3 && strKey[0]=='-' && strKey[1]=='n' && strKey[2]=='o')
 337     {
 338         strKey = "-" + strKey.substr(3);
 339         strValue = InterpretBool(strValue) ? "0" : "1";
 340     }
 341 }
 342
 343 void ParseParameters(int argc, const char* const argv[])
 344 {
 345     mapArgs.clear();
 346     mapMultiArgs.clear();
 347
 348     for (int i = 1; i < argc; i++)
 349     {
 350         std::string str(argv[i]);
 351         std::string strValue;
 352         size_t is_index = str.find('=');
 353         if (is_index != std::string::npos)
 354         {
 355             strValue = str.substr(is_index+1);
 356             str = str.substr(0, is_index);
 357         }
 358 #ifdef WIN32
 359         boost::to_lower(str);
 360         if (boost::algorithm::starts_with(str, "/"))
 361             str = "-" + str.substr(1);
 362 #endif
 363
 364         if (str[0] != '-')
 365             break;
 366
 367         // Interpret --foo as -foo.
 368         // If both --foo and -foo are set, the last takes effect.
 369         if (str.length() > 1 && str[1] == '-')
 370             str = str.substr(1);
 371         InterpretNegativeSetting(str, strValue);
 372
 373         mapArgs[str] = strValue;
 374         mapMultiArgs[str].push_back(strValue);
 375     }
 376 }
 377
 378 std::string GetArg(const std::string& strArg, const std::string& strDefault)
 379 {
 380     if (mapArgs.count(strArg))
 381         return mapArgs[strArg];
 382     return strDefault;
 383 }
 384
 385 int64_t GetArg(const std::string& strArg, int64_t nDefault)
 386 {
 387     if (mapArgs.count(strArg))
 388         return atoi64(mapArgs[strArg]);
 389     return nDefault;
 390 }
 391
 392 bool GetBoolArg(const std::string& strArg, bool fDefault)
 393 {
 394     if (mapArgs.count(strArg))
 395         return InterpretBool(mapArgs[strArg]);
 396     return fDefault;
 397 }
 398
 399 bool SoftSetArg(const std::string& strArg, const std::string& strValue)
 400 {
 401     if (mapArgs.count(strArg))
 402         return false;
 403     mapArgs[strArg] = strValue;
 404     return true;
 405 }
 406
 407 bool SoftSetBoolArg(const std::string& strArg, bool fValue)
 408 {
 409     if (fValue)
 410         return SoftSetArg(strArg, std::string("1"));
 411     else
 412         return SoftSetArg(strArg, std::string("0"));
 413 }
 414
 415 static const int screenWidth = 79;
 416 static const int optIndent = 2;
 417 static const int msgIndent = 7;
 418
 419 std::string HelpMessageGroup(const std::string &message) {
 420     return std::string(message) + std::string("\n\n");
 421 }
 422
 423 std::string HelpMessageOpt(const std::string &option, const std::string &message) {
 424     return std::string(optIndent,' ') + std::string(option) +
 425            std::string("\n") + std::string(msgIndent,' ') +
 426            FormatParagraph(message, screenWidth - msgIndent, msgIndent) +
 427            std::string("\n\n");
 428 }
 429
 430 static std::string FormatException(const std::exception* pex, const char* pszThread)
 431 {
 432 #ifdef WIN32
 433     char pszModule[MAX_PATH] = "";
 434     GetModuleFileNameA(NULL, pszModule, sizeof(pszModule));
 435 #else
 436     const char* pszModule = "bitcoin";
 437 #endif
 438     if (pex)
 439         return strprintf(
 440             "EXCEPTION: %s       \n%s       \n%s in %s       \n", typeid(*pex).name(), pex->what(), pszModule, pszThread);
 441     else
 442         return strprintf(
 443             "UNKNOWN EXCEPTION       \n%s in %s       \n", pszModule, pszThread);
 444 }
 445
 446 void PrintExceptionContinue(const std::exception* pex, const char* pszThread)
 447 {
 448     std::string message = FormatException(pex, pszThread);
 449     LogPrintf("\n\n************************\n%s\n", message);
 450     fprintf(stderr, "\n\n************************\n%s\n", message.c_str());
 451 }
 452
 453 boost::filesystem::path GetDefaultDataDir()
 454 {
 455     namespace fs = boost::filesystem;
 456     // Windows < Vista: C:\Documents and Settings\Username\Application Data\Bitcoin
 457     // Windows >= Vista: C:\Users\Username\AppData\Roaming\Bitcoin
 458     // Mac: ~/Library/Application Support/Bitcoin
 459     // Unix: ~/.bitcoin
 460 #ifdef WIN32
 461     // Windows
 462     return GetSpecialFolderPath(CSIDL_APPDATA) / "Bitcoin";
 463 #else
 464     fs::path pathRet;
 465     char* pszHome = getenv("HOME");
 466     if (pszHome == NULL || strlen(pszHome) == 0)
 467         pathRet = fs::path("/");
 468     else
 469         pathRet = fs::path(pszHome);
 470 #ifdef MAC_OSX
 471     // Mac
 472     return pathRet / "Library/Application Support/Bitcoin";
 473 #else
 474     // Unix
 475     return pathRet / ".bitcoin";
 476 #endif
 477 #endif
 478 }
 479
 480 static boost::filesystem::path pathCached;
 481 static boost::filesystem::path pathCachedNetSpecific;
 482 static CCriticalSection csPathCached;
 483
 484 const boost::filesystem::path &GetDataDir(bool fNetSpecific)
 485 {
 486     namespace fs = boost::filesystem;
 487
 488     LOCK(csPathCached);
 489
 490     fs::path &path = fNetSpecific ? pathCachedNetSpecific : pathCached;
 491
 492     // This can be called during exceptions by LogPrintf(), so we cache the
 493     // value so we don't have to do memory allocations after that.
 494     if (!path.empty())
 495         return path;
 496
 497     if (mapArgs.count("-datadir")) {
 498         path = fs::system_complete(mapArgs["-datadir"]);
 499         if (!fs::is_directory(path)) {
 500             path = "";
 501             return path;
 502         }
 503     } else {
 504         path = GetDefaultDataDir();
 505     }
 506     if (fNetSpecific)
 507         path /= BaseParams().DataDir();
 508
 509     fs::create_directories(path);
 510
 511     return path;
 512 }
 513
 514 void ClearDatadirCache()
 515 {
 516     pathCached = boost::filesystem::path();
 517     pathCachedNetSpecific = boost::filesystem::path();
 518 }
 519
 520 boost::filesystem::path GetConfigFile(const std::string& confPath)
 521 {
 522     boost::filesystem::path pathConfigFile(confPath);
 523     if (!pathConfigFile.is_complete())
 524         pathConfigFile = GetDataDir(false) / pathConfigFile;
 525
 526     return pathConfigFile;
 527 }
 528
 529 void ReadConfigFile(const std::string& confPath,
 530                     map<string, string>& mapSettingsRet,
 531                     map<string, vector<string> >& mapMultiSettingsRet)
 532 {
 533     boost::filesystem::ifstream streamConfig(GetConfigFile(confPath));
 534     if (!streamConfig.good())
 535         return; // No bitcoin.conf file is OK
 536
 537     set<string> setOptions;
 538     setOptions.insert("*");
 539
 540     for (boost::program_options::detail::config_file_iterator it(streamConfig, setOptions), end; it != end; ++it)
 541     {
 542         // Don't overwrite existing settings so command line settings override bitcoin.conf
 543         string strKey = string("-") + it->string_key;
 544         string strValue = it->value[0];
 545         InterpretNegativeSetting(strKey, strValue);
 546         if (mapSettingsRet.count(strKey) == 0)
 547             mapSettingsRet[strKey] = strValue;
 548         mapMultiSettingsRet[strKey].push_back(strValue);
 549     }
 550     // If datadir is changed in .conf file:
 551     ClearDatadirCache();
 552 }
 553
 554 #ifndef WIN32
 555 boost::filesystem::path GetPidFile()
 556 {
 557     boost::filesystem::path pathPidFile(GetArg("-pid", BITCOIN_PID_FILENAME));
 558     if (!pathPidFile.is_complete()) pathPidFile = GetDataDir() / pathPidFile;
 559     return pathPidFile;
 560 }
 561
 562 void CreatePidFile(const boost::filesystem::path &path, pid_t pid)
 563 {
 564     FILE* file = fopen(path.string().c_str(), "w");
 565     if (file)
 566     {
 567         fprintf(file, "%d\n", pid);
 568         fclose(file);
 569     }
 570 }
 571 #endif
 572
 573 bool RenameOver(boost::filesystem::path src, boost::filesystem::path dest)
 574 {
 575 #ifdef WIN32
 576     return MoveFileExA(src.string().c_str(), dest.string().c_str(),
 577                        MOVEFILE_REPLACE_EXISTING) != 0;
 578 #else
 579     int rc = std::rename(src.string().c_str(), dest.string().c_str());
 580     return (rc == 0);
 581 #endif /* WIN32 */
 582 }
 583
 584 /**
 585  * Ignores exceptions thrown by Boost's create_directory if the requested directory exists.
 586  * Specifically handles case where path p exists, but it wasn't possible for the user to
 587  * write to the parent directory.
 588  */
 589 bool TryCreateDirectory(const boost::filesystem::path& p)
 590 {
 591     try
 592     {
 593         return boost::filesystem::create_directory(p);
 594     } catch (const boost::filesystem::filesystem_error&) {
 595         if (!boost::filesystem::exists(p) || !boost::filesystem::is_directory(p))
 596             throw;
 597     }
 598
 599     // create_directory didn't create the directory, it had to have existed already
 600     return false;
 601 }
 602
 603 void FileCommit(FILE *file)
 604 {
 605     fflush(file); // harmless if redundantly called
 606 #ifdef WIN32
 607     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 608     FlushFileBuffers(hFile);
 609 #else
 610     #if defined(__linux__) || defined(__NetBSD__)
 611     fdatasync(fileno(file));
 612     #elif defined(__APPLE__) && defined(F_FULLFSYNC)
 613     fcntl(fileno(file), F_FULLFSYNC, 0);
 614     #else
 615     fsync(fileno(file));
 616     #endif
 617 #endif
 618 }
 619
 620 bool TruncateFile(FILE *file, unsigned int length) {
 621 #if defined(WIN32)
 622     return _chsize(_fileno(file), length) == 0;
 623 #else
 624     return ftruncate(fileno(file), length) == 0;
 625 #endif
 626 }
 627
 628 /**
 629  * this function tries to raise the file descriptor limit to the requested number.
 630  * It returns the actual file descriptor limit (which may be more or less than nMinFD)
 631  */
 632 int RaiseFileDescriptorLimit(int nMinFD) {
 633 #if defined(WIN32)
 634     return 2048;
 635 #else
 636     struct rlimit limitFD;
 637     if (getrlimit(RLIMIT_NOFILE, &limitFD) != -1) {
 638         if (limitFD.rlim_cur < (rlim_t)nMinFD) {
 639             limitFD.rlim_cur = nMinFD;
 640             if (limitFD.rlim_cur > limitFD.rlim_max)
 641                 limitFD.rlim_cur = limitFD.rlim_max;
 642             setrlimit(RLIMIT_NOFILE, &limitFD);
 643             getrlimit(RLIMIT_NOFILE, &limitFD);
 644         }
 645         return limitFD.rlim_cur;
 646     }
 647     return nMinFD; // getrlimit failed, assume it's fine
 648 #endif
 649 }
 650
 651 /**
 652  * this function tries to make a particular range of a file allocated (corresponding to disk space)
 653  * it is advisory, and the range specified in the arguments will never contain live data
 654  */
 655 void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length) {
 656 #if defined(WIN32)
 657     // Windows-specific version
 658     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
 659     LARGE_INTEGER nFileSize;
 660     int64_t nEndPos = (int64_t)offset + length;
 661     nFileSize.u.LowPart = nEndPos & 0xFFFFFFFF;
 662     nFileSize.u.HighPart = nEndPos >> 32;
 663     SetFilePointerEx(hFile, nFileSize, 0, FILE_BEGIN);
 664     SetEndOfFile(hFile);
 665 #elif defined(MAC_OSX)
 666     // OSX specific version
 667     fstore_t fst;
 668     fst.fst_flags = F_ALLOCATECONTIG;
 669     fst.fst_posmode = F_PEOFPOSMODE;
 670     fst.fst_offset = 0;
 671     fst.fst_length = (off_t)offset + length;
 672     fst.fst_bytesalloc = 0;
 673     if (fcntl(fileno(file), F_PREALLOCATE, &fst) == -1) {
 674         fst.fst_flags = F_ALLOCATEALL;
 675         fcntl(fileno(file), F_PREALLOCATE, &fst);
 676     }
 677     ftruncate(fileno(file), fst.fst_length);
 678 #elif defined(__linux__)
 679     // Version using posix_fallocate
 680     off_t nEndPos = (off_t)offset + length;
 681     posix_fallocate(fileno(file), 0, nEndPos);
 682 #else
 683     // Fallback version
 684     // TODO: just write one byte per block
 685     static const char buf[65536] = {};
 686     fseek(file, offset, SEEK_SET);
 687     while (length > 0) {
 688         unsigned int now = 65536;
 689         if (length < now)
 690             now = length;
 691         fwrite(buf, 1, now, file); // allowed to fail; this function is advisory anyway
 692         length -= now;
 693     }
 694 #endif
 695 }
 696
 697 void ShrinkDebugFile()
 698 {
 699     // Scroll debug.log if it's getting too big
 700     boost::filesystem::path pathLog = GetDataDir() / "debug.log";
 701     FILE* file = fopen(pathLog.string().c_str(), "r");
 702     if (file && boost::filesystem::file_size(pathLog) > 10 * 1000000)
 703     {
 704         // Restart the file with some of the end
 705         std::vector <char> vch(200000,0);
 706         fseek(file, -((long)vch.size()), SEEK_END);
 707         int nBytes = fread(begin_ptr(vch), 1, vch.size(), file);
 708         fclose(file);
 709
 710         file = fopen(pathLog.string().c_str(), "w");
 711         if (file)
 712         {
 713             fwrite(begin_ptr(vch), 1, nBytes, file);
 714             fclose(file);
 715         }
 716     }
 717     else if (file != NULL)
 718         fclose(file);
 719 }
 720
 721 #ifdef WIN32
 722 boost::filesystem::path GetSpecialFolderPath(int nFolder, bool fCreate)
 723 {
 724     namespace fs = boost::filesystem;
 725
 726     char pszPath[MAX_PATH] = "";
 727
 728     if(SHGetSpecialFolderPathA(NULL, pszPath, nFolder, fCreate))
 729     {
 730         return fs::path(pszPath);
 731     }
 732
 733     LogPrintf("SHGetSpecialFolderPathA() failed, could not obtain requested path.\n");
 734     return fs::path("");
 735 }
 736 #endif
 737
 738 void runCommand(const std::string& strCommand)
 739 {
 740     int nErr = ::system(strCommand.c_str());
 741     if (nErr)
 742         LogPrintf("runCommand error: system(%s) returned %d\n", strCommand, nErr);
 743 }
 744
 745 void RenameThread(const char* name)
 746 {
 747 #if defined(PR_SET_NAME)
 748     // Only the first 15 characters are used (16 - NUL terminator)
 749     ::prctl(PR_SET_NAME, name, 0, 0, 0);
 750 #elif (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
 751     pthread_set_name_np(pthread_self(), name);
 752
 753 #elif defined(MAC_OSX)
 754     pthread_setname_np(name);
 755 #else
 756     // Prevent warnings for unused parameters...
 757     (void)name;
 758 #endif
 759 }
 760
 761 void SetupEnvironment()
 762 {
 763     // On most POSIX systems (e.g. Linux, but not BSD) the environment's locale
 764     // may be invalid, in which case the "C" locale is used as fallback.
 765 #if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
 766     try {
 767         std::locale(""); // Raises a runtime error if current locale is invalid
 768     } catch (const std::runtime_error&) {
 769         setenv("LC_ALL", "C", 1);
 770     }
 771 #endif
 772     // The path locale is lazy initialized and to avoid deinitialization errors
 773     // in multithreading environments, it is set explicitly by the main thread.
 774     // A dummy locale is used to extract the internal default locale, used by
 775     // boost::filesystem::path, which is then used to explicitly imbue the path.
 776     std::locale loc = boost::filesystem::path::imbue(std::locale::classic());
 777     boost::filesystem::path::imbue(loc);
 778 }
 779
 780 bool SetupNetworking()
 781 {
 782 #ifdef WIN32
 783     // Initialize Windows Sockets
 784     WSADATA wsadata;
 785     int ret = WSAStartup(MAKEWORD(2,2), &wsadata);
 786     if (ret != NO_ERROR || LOBYTE(wsadata.wVersion ) != 2 || HIBYTE(wsadata.wVersion) != 2)
 787         return false;
 788 #endif
 789     return true;
 790 }
 791
 792 int GetNumCores()
 793 {
 794 #if BOOST_VERSION >= 105600
 795     return boost::thread::physical_concurrency();
 796 #else // Must fall back to hardware_concurrency, which unfortunately counts virtual cores
 797     return boost::thread::hardware_concurrency();
 798 #endif
 799 }
 800
 801 std::string CopyrightHolders(const std::string& strPrefix)
 802 {
 803     std::string strCopyrightHolders = strPrefix + strprintf(_(COPYRIGHT_HOLDERS), _(COPYRIGHT_HOLDERS_SUBSTITUTION));
 804
 805     // Check for untranslated substitution to make sure Bitcoin Core copyright is not removed by accident
 806     if (strprintf(COPYRIGHT_HOLDERS, COPYRIGHT_HOLDERS_SUBSTITUTION).find("Bitcoin Core") == std::string::npos) {
 807         strCopyrightHolders += "\n" + strPrefix + "The Bitcoin Core developers";
 808     }
 809     return strCopyrightHolders;
 810 }