/*============================================================================
  CMake - Cross Platform Makefile Generator
  Copyright 2000-2009 Kitware, Inc., Insight Software Consortium

  Distributed under the OSI-approved BSD License (the "License");
  see accompanying file Copyright.txt for details.

  This software is distributed WITHOUT ANY WARRANTY; without even the
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the License for more information.
============================================================================*/

#include "cmSystemTools.h"
#include "cmAlgorithms.h"
#include <ctype.h>
#include <errno.h>
#include <time.h>
#include <string.h>
#include <stdlib.h>
#ifdef __QNX__
# include <malloc.h> /* for malloc/free on QNX */
#endif
#include <cmsys/Glob.hxx>
#include <cmsys/RegularExpression.hxx>
#include <cmsys/Directory.hxx>
#include <cmsys/System.h>
#include <cmsys/Encoding.hxx>
#if defined(CMAKE_BUILD_WITH_CMAKE)
# include "cmArchiveWrite.h"
# include "cmLocale.h"
# include <cm_libarchive.h>
#endif
#include <cmsys/stl/algorithm>
#include <cmsys/FStream.hxx>
#include <cmsys/Terminal.h>

#if defined(_WIN32)
# include <windows.h>
# include <wincrypt.h>
#else
# include <sys/time.h>
# include <sys/types.h>
# include <unistd.h>
# include <utime.h>
# include <sys/wait.h>
#endif

#if defined(__APPLE__)
# include <mach-o/dyld.h>
#endif

#include <sys/stat.h>

#if defined(_WIN32) && \
   (defined(_MSC_VER) || defined(__WATCOMC__) || defined(__MINGW32__))
# include <io.h>
#endif

#if defined(CMAKE_BUILD_WITH_CMAKE)
#  include <fcntl.h>
#  include "cmCryptoHash.h"
#endif

#if defined(CMAKE_USE_ELF_PARSER)
# include "cmELF.h"
#endif

#if defined(CMAKE_USE_MACH_PARSER)
# include "cmMachO.h"
#endif

class cmSystemToolsFileTime
{
public:
#if defined(_WIN32) && !defined(__CYGWIN__)
  FILETIME timeCreation;
  FILETIME timeLastAccess;
  FILETIME timeLastWrite;
#else
  struct utimbuf timeBuf;
#endif
};

#if !defined(HAVE_ENVIRON_NOT_REQUIRE_PROTOTYPE)
// For GetEnvironmentVariables
# if defined(_WIN32)
extern __declspec( dllimport ) char** environ;
# else
extern char** environ;
# endif
#endif

#if defined(CMAKE_BUILD_WITH_CMAKE)
static std::string
cm_archive_entry_pathname(struct archive_entry *entry)
{
#if cmsys_STL_HAS_WSTRING
  return cmsys::Encoding::ToNarrow(
    archive_entry_pathname_w(entry));
#else
  return archive_entry_pathname(entry);
#endif
}

static int cm_archive_read_open_file(struct archive* a,
                                     const char* file,
                                     int block_size)
{
#if cmsys_STL_HAS_WSTRING
  std::wstring wfile = cmsys::Encoding::ToWide(file);
  return archive_read_open_filename_w(a, wfile.c_str(), block_size);
#else
  return archive_read_open_filename(a, file, block_size);
#endif
}
#endif

#ifdef _WIN32
class cmSystemToolsWindowsHandle
{
public:
  cmSystemToolsWindowsHandle(HANDLE h): handle_(h) {}
  ~cmSystemToolsWindowsHandle()
    {
    if(this->handle_ != INVALID_HANDLE_VALUE)
      {
      CloseHandle(this->handle_);
      }
    }
  operator bool() const { return this->handle_ != INVALID_HANDLE_VALUE; }
  bool operator !() const { return this->handle_ == INVALID_HANDLE_VALUE; }
  operator HANDLE() const { return this->handle_; }
private:
  HANDLE handle_;
};
#elif defined(__APPLE__)
#include <crt_externs.h>
#define environ (*_NSGetEnviron())
#endif

bool cmSystemTools::s_RunCommandHideConsole = false;
bool cmSystemTools::s_DisableRunCommandOutput = false;
bool cmSystemTools::s_ErrorOccured = false;
bool cmSystemTools::s_FatalErrorOccured = false;
bool cmSystemTools::s_DisableMessages = false;
bool cmSystemTools::s_ForceUnixPaths = false;

cmSystemTools::MessageCallback cmSystemTools::s_MessageCallback;
cmSystemTools::OutputCallback cmSystemTools::s_StdoutCallback;
cmSystemTools::OutputCallback cmSystemTools::s_StderrCallback;
cmSystemTools::InterruptCallback cmSystemTools::s_InterruptCallback;
void* cmSystemTools::s_MessageCallbackClientData;
void* cmSystemTools::s_StdoutCallbackClientData;
void* cmSystemTools::s_StderrCallbackClientData;
void* cmSystemTools::s_InterruptCallbackClientData;

// replace replace with with as many times as it shows up in source.
// write the result into source.
#if defined(_WIN32) && !defined(__CYGWIN__)
void cmSystemTools::ExpandRegistryValues(std::string& source, KeyWOW64 view)
{
  // Regular expression to match anything inside [...] that begins in HKEY.
  // Note that there is a special rule for regular expressions to match a
  // close square-bracket inside a list delimited by square brackets.
  // The "[^]]" part of this expression will match any character except
  // a close square-bracket.  The ']' character must be the first in the
  // list of characters inside the [^...] block of the expression.
  cmsys::RegularExpression regEntry("\\[(HKEY[^]]*)\\]");

  // check for black line or comment
  while (regEntry.find(source))
    {
    // the arguments are the second match
    std::string key = regEntry.match(1);
    std::string val;
    if (ReadRegistryValue(key.c_str(), val, view))
      {
      std::string reg = "[";
      reg += key + "]";
      cmSystemTools::ReplaceString(source, reg.c_str(), val.c_str());
      }
    else
      {
      std::string reg = "[";
      reg += key + "]";
      cmSystemTools::ReplaceString(source, reg.c_str(), "/registry");
      }
    }
}
#else
void cmSystemTools::ExpandRegistryValues(std::string& source, KeyWOW64)
{
  cmsys::RegularExpression regEntry("\\[(HKEY[^]]*)\\]");
  while (regEntry.find(source))
    {
    // the arguments are the second match
    std::string key = regEntry.match(1);
    std::string val;
    std::string reg = "[";
    reg += key + "]";
    cmSystemTools::ReplaceString(source, reg.c_str(), "/registry");
    }

}
#endif

std::string cmSystemTools::EscapeQuotes(const std::string& str)
{
  std::string result;
  result.reserve(str.size());
  for(const char* ch = str.c_str(); *ch != '\0'; ++ch)
    {
    if(*ch == '"')
      {
      result += '\\';
      }
    result += *ch;
    }
  return result;
}

std::string cmSystemTools::HelpFileName(std::string name)
{
  cmSystemTools::ReplaceString(name, "<", "");
  cmSystemTools::ReplaceString(name, ">", "");
  return name;
}

std::string cmSystemTools::TrimWhitespace(const std::string& s)
{
  std::string::const_iterator start = s.begin();
  while(start != s.end() && *start <= ' ')
    ++start;
  if (start == s.end())
    return "";

  std::string::const_iterator stop = s.end()-1;
  while(*stop <= ' ')
    --stop;
  return std::string(start, stop+1);
}

void cmSystemTools::Error(const char* m1, const char* m2,
                          const char* m3, const char* m4)
{
  std::string message = "CMake Error: ";
  if(m1)
    {
    message += m1;
    }
  if(m2)
    {
    message += m2;
    }
  if(m3)
    {
    message += m3;
    }
  if(m4)
    {
    message += m4;
    }
  cmSystemTools::s_ErrorOccured = true;
  cmSystemTools::Message(message.c_str(),"Error");
}

void cmSystemTools::SetInterruptCallback(InterruptCallback f, void* clientData)
{
  s_InterruptCallback = f;
  s_InterruptCallbackClientData = clientData;
}

bool cmSystemTools::GetInterruptFlag()
{
  if(s_InterruptCallback)
    {
    return (*s_InterruptCallback)(s_InterruptCallbackClientData);
    }
  return false;
}

void cmSystemTools::SetMessageCallback(MessageCallback f, void* clientData)
{
  s_MessageCallback = f;
  s_MessageCallbackClientData = clientData;
}

void cmSystemTools::SetStdoutCallback(OutputCallback f, void* clientData)
{
  s_StdoutCallback = f;
  s_StdoutCallbackClientData = clientData;
}

void cmSystemTools::SetStderrCallback(OutputCallback f, void* clientData)
{
  s_StderrCallback = f;
  s_StderrCallbackClientData = clientData;
}

void cmSystemTools::Stdout(const char* s)
{
  cmSystemTools::Stdout(s, strlen(s));
}

void cmSystemTools::Stderr(const char* s)
{
  cmSystemTools::Stderr(s, strlen(s));
}

void cmSystemTools::Stderr(const char* s, size_t length)
{
  if(s_StderrCallback)
    {
    (*s_StderrCallback)(s, length, s_StderrCallbackClientData);
    }
  else
    {
    std::cerr.write(s, length);
    std::cerr.flush();
    }
}

void cmSystemTools::Stdout(const char* s, size_t length)
{
  if(s_StdoutCallback)
    {
    (*s_StdoutCallback)(s, length, s_StdoutCallbackClientData);
    }
  else
    {
    std::cout.write(s, length);
    std::cout.flush();
    }
}

void cmSystemTools::Message(const char* m1, const char *title)
{
  if(s_DisableMessages)
    {
    return;
    }
  if(s_MessageCallback)
    {
    (*s_MessageCallback)(m1, title, s_DisableMessages,
                         s_MessageCallbackClientData);
    return;
    }
  else
    {
    std::cerr << m1 << std::endl << std::flush;
    }

}


void cmSystemTools::ReportLastSystemError(const char* msg)
{
  std::string m = msg;
  m += ": System Error: ";
  m += Superclass::GetLastSystemError();
  cmSystemTools::Error(m.c_str());
}

bool cmSystemTools::IsInternallyOn(const char* val)
{
  if (!val)
    {
    return false;
    }
  std::basic_string<char> v = val;
  if (v.size() > 4)
    {
    return false;
    }

  for(std::basic_string<char>::iterator c = v.begin();
      c != v.end(); c++)
    {
    *c = static_cast<char>(toupper(*c));
    }
  return v == "I_ON";
}

bool cmSystemTools::IsOn(const char* val)
{
  if (!val)
    {
    return false;
    }
  size_t len = strlen(val);
  if (len > 4)
    {
    return false;
    }
  std::basic_string<char> v(val, len);

  static std::set<std::string> onValues;
  if(onValues.empty())
    {
    onValues.insert("ON");
    onValues.insert("1");
    onValues.insert("YES");
    onValues.insert("TRUE");
    onValues.insert("Y");
    }
  for(std::basic_string<char>::iterator c = v.begin();
      c != v.end(); c++)
    {
    *c = static_cast<char>(toupper(*c));
    }
  return (onValues.count(v) > 0);
}

bool cmSystemTools::IsNOTFOUND(const char* val)
{
  if(strcmp(val, "NOTFOUND") == 0)
    {
    return true;
    }
  return cmHasLiteralSuffix(val, "-NOTFOUND");
}


bool cmSystemTools::IsOff(const char* val)
{
  if (!val || !*val)
    {
    return true;
    }
  size_t len = strlen(val);
  // Try and avoid toupper() for large strings.
  if (len > 6)
    {
    return cmSystemTools::IsNOTFOUND(val);
    }

  static std::set<std::string> offValues;
  if(offValues.empty())
    {
    offValues.insert("OFF");
    offValues.insert("0");
    offValues.insert("NO");
    offValues.insert("FALSE");
    offValues.insert("N");
    offValues.insert("IGNORE");
    }
  // Try and avoid toupper().
  std::basic_string<char> v(val, len);
  for(std::basic_string<char>::iterator c = v.begin();
      c != v.end(); c++)
    {
    *c = static_cast<char>(toupper(*c));
    }
  return (offValues.count(v) > 0);
}

//----------------------------------------------------------------------------
void cmSystemTools::ParseWindowsCommandLine(const char* command,
                                            std::vector<std::string>& args)
{
  // See the MSDN document "Parsing C Command-Line Arguments" at
  // http://msdn2.microsoft.com/en-us/library/a1y7w461.aspx for rules
  // of parsing the windows command line.

  bool in_argument = false;
  bool in_quotes = false;
  int backslashes = 0;
  std::string arg;
  for(const char* c = command;*c; ++c)
    {
    if(*c == '\\')
      {
      ++backslashes;
      in_argument = true;
      }
    else if(*c == '"')
      {
      int backslash_pairs  = backslashes >> 1;
      int backslash_escaped = backslashes & 1;
      arg.append(backslash_pairs, '\\');
      backslashes = 0;
      if(backslash_escaped)
        {
        /* An odd number of backslashes precede this quote.
           It is escaped.  */
        arg.append(1, '"');
        }
      else
        {
        /* An even number of backslashes precede this quote.
           It is not escaped.  */
        in_quotes = !in_quotes;
        }
      in_argument = true;
      }
    else
      {
      arg.append(backslashes, '\\');
      backslashes = 0;
      if(((*c & 0x80) == 0 ) && isspace(*c))
        {
        if(in_quotes)
          {
          arg.append(1, *c);
          }
        else if(in_argument)
          {
          args.push_back(arg);
          arg = "";
          in_argument = false;
          }
        }
      else
        {
        in_argument = true;
        arg.append(1, *c);
        }
      }
    }
  arg.append(backslashes, '\\');
  if(in_argument)
    {
    args.push_back(arg);
    }
}

//----------------------------------------------------------------------------
class cmSystemToolsArgV
{
  char** ArgV;
public:
  cmSystemToolsArgV(char** argv): ArgV(argv) {}
  ~cmSystemToolsArgV()
    {
    for(char** arg = this->ArgV; arg && *arg; ++arg)
      {
      free(*arg);
      }
    free(this->ArgV);
    }
  void Store(std::vector<std::string>& args) const
    {
    for(char** arg = this->ArgV; arg && *arg; ++arg)
      {
      args.push_back(*arg);
      }
    }
};

//----------------------------------------------------------------------------
void cmSystemTools::ParseUnixCommandLine(const char* command,
                                         std::vector<std::string>& args)
{
  // Invoke the underlying parser.
  cmSystemToolsArgV argv = cmsysSystem_Parse_CommandForUnix(command, 0);
  argv.Store(args);
}

std::string cmSystemTools::EscapeWindowsShellArgument(const char* arg,
                                                      int shell_flags)
{
  char local_buffer[1024];
  char* buffer = local_buffer;
  int size = cmsysSystem_Shell_GetArgumentSizeForWindows(arg, shell_flags);
  if(size > 1024)
    {
    buffer = new char[size];
    }
  cmsysSystem_Shell_GetArgumentForWindows(arg, buffer, shell_flags);
  std::string result(buffer);
  if(buffer != local_buffer)
    {
    delete [] buffer;
    }
  return result;
}

std::vector<std::string> cmSystemTools::ParseArguments(const char* command)
{
  std::vector<std::string> args;
  std::string arg;

  bool win_path = false;

  if ((command[0] != '/' && command[1] == ':' && command[2] == '\\') ||
      (command[0] == '\"' && command[1] != '/' && command[2] == ':'
       && command[3] == '\\') ||
      (command[0] == '\'' && command[1] != '/' && command[2] == ':'
       && command[3] == '\\') ||
      (command[0] == '\\' && command[1] == '\\'))
    {
    win_path = true;
    }
  // Split the command into an argv array.
  for(const char* c = command; *c;)
    {
    // Skip over whitespace.
    while(*c == ' ' || *c == '\t')
      {
      ++c;
      }
    arg = "";
    if(*c == '"')
      {
      // Parse a quoted argument.
      ++c;
      while(*c && *c != '"')
        {
        arg.append(1, *c);
        ++c;
        }
      if(*c)
        {
        ++c;
        }
      args.push_back(arg);
      }
    else if(*c == '\'')
      {
      // Parse a quoted argument.
      ++c;
      while(*c && *c != '\'')
        {
        arg.append(1, *c);
        ++c;
        }
      if(*c)
        {
        ++c;
        }
      args.push_back(arg);
      }
    else if(*c)
      {
      // Parse an unquoted argument.
      while(*c && *c != ' ' && *c != '\t')
        {
        if(*c == '\\' && !win_path)
          {
          ++c;
          if(*c)
            {
            arg.append(1, *c);
            ++c;
            }
          }
        else
          {
          arg.append(1, *c);
          ++c;
          }
        }
      args.push_back(arg);
      }
    }

  return args;
}


bool cmSystemTools::RunSingleCommand(std::vector<std::string>const& command,
                                     std::string* captureStdOut,
                                     std::string* captureStdErr,
                                     int* retVal , const char* dir ,
                                     OutputOption outputflag ,
                                     double timeout )
{
  std::vector<const char*> argv;
  for(std::vector<std::string>::const_iterator a = command.begin();
      a != command.end(); ++a)
    {
    argv.push_back(a->c_str());
    }
  argv.push_back(0);
  if ( captureStdOut )
    {
    *captureStdOut = "";
    }
  if (captureStdErr && captureStdErr != captureStdOut)
    {
    *captureStdErr = "";
    }

  cmsysProcess* cp = cmsysProcess_New();
  cmsysProcess_SetCommand(cp, &*argv.begin());
  cmsysProcess_SetWorkingDirectory(cp, dir);
  if(cmSystemTools::GetRunCommandHideConsole())
    {
    cmsysProcess_SetOption(cp, cmsysProcess_Option_HideWindow, 1);
    }

  if (outputflag == OUTPUT_PASSTHROUGH)
    {
    cmsysProcess_SetPipeShared(cp, cmsysProcess_Pipe_STDOUT, 1);
    cmsysProcess_SetPipeShared(cp, cmsysProcess_Pipe_STDERR, 1);
    }

  cmsysProcess_SetTimeout(cp, timeout);
  cmsysProcess_Execute(cp);

  std::vector<char> tempStdOut;
  std::vector<char> tempStdErr;
  char* data;
  int length;
  int pipe;
  if(outputflag != OUTPUT_PASSTHROUGH &&
     (captureStdOut || captureStdErr || outputflag != OUTPUT_NONE))
    {
    while((pipe = cmsysProcess_WaitForData(cp, &data, &length, 0)) > 0)
      {
      if(captureStdOut || captureStdErr || outputflag != OUTPUT_NONE)
        {
        // Translate NULL characters in the output into valid text.
        // Visual Studio 7 puts these characters in the output of its
        // build process.
        for(int i=0; i < length; ++i)
          {
          if(data[i] == '\0')
            {
            data[i] = ' ';
            }
          }
        }
      if(pipe == cmsysProcess_Pipe_STDOUT ||
         (pipe == cmsysProcess_Pipe_STDERR &&
          captureStdOut == captureStdErr))
        {
        if (captureStdOut)
          {
          tempStdOut.insert(tempStdOut.end(), data, data+length);
          }
        }
      else if(pipe == cmsysProcess_Pipe_STDERR)
        {
        if (captureStdErr)
          {
          tempStdErr.insert(tempStdErr.end(), data, data+length);
          }
        }
      if(outputflag != OUTPUT_NONE)
        {
        if(outputflag == OUTPUT_MERGE)
          {
          cmSystemTools::Stdout(data, length);
          }
        else
          {
          if(pipe == cmsysProcess_Pipe_STDERR)
            {
            cmSystemTools::Stderr(data, length);
            }
          else if(pipe == cmsysProcess_Pipe_STDOUT)
            {
            cmSystemTools::Stdout(data, length);
            }
          }
        }
      }
    }

  cmsysProcess_WaitForExit(cp, 0);
  if ( captureStdOut && tempStdOut.begin() != tempStdOut.end())
    {
    captureStdOut->append(&*tempStdOut.begin(), tempStdOut.size());
    }
  if ( captureStdErr && captureStdErr != captureStdOut &&
       tempStdErr.begin() != tempStdErr.end())
    {
    captureStdErr->append(&*tempStdErr.begin(), tempStdErr.size());
    }

  bool result = true;
  if(cmsysProcess_GetState(cp) == cmsysProcess_State_Exited)
    {
    if ( retVal )
      {
      *retVal = cmsysProcess_GetExitValue(cp);
      }
    else
      {
      if ( cmsysProcess_GetExitValue(cp) !=  0 )
        {
        result = false;
        }
      }
    }
  else if(cmsysProcess_GetState(cp) == cmsysProcess_State_Exception)
    {
    const char* exception_str = cmsysProcess_GetExceptionString(cp);
    if ( outputflag != OUTPUT_NONE )
      {
      std::cerr << exception_str << std::endl;
      }
    if ( captureStdErr )
      {
      captureStdErr->append(exception_str, strlen(exception_str));
      }
    result = false;
    }
  else if(cmsysProcess_GetState(cp) == cmsysProcess_State_Error)
    {
    const char* error_str = cmsysProcess_GetErrorString(cp);
    if ( outputflag != OUTPUT_NONE )
      {
      std::cerr << error_str << std::endl;
      }
    if ( captureStdErr )
      {
      captureStdErr->append(error_str, strlen(error_str));
      }
    result = false;
    }
  else if(cmsysProcess_GetState(cp) == cmsysProcess_State_Expired)
    {
    const char* error_str = "Process terminated due to timeout\n";
    if ( outputflag != OUTPUT_NONE )
      {
      std::cerr << error_str << std::endl;
      }
    if ( captureStdErr )
      {
      captureStdErr->append(error_str, strlen(error_str));
      }
    result = false;
    }

  cmsysProcess_Delete(cp);
  return result;
}

bool cmSystemTools::RunSingleCommand(
  const char* command,
  std::string* captureStdOut,
  std::string* captureStdErr,
  int *retVal,
  const char* dir,
  OutputOption outputflag,
  double timeout)
{
  if(s_DisableRunCommandOutput)
    {
    outputflag = OUTPUT_NONE;
    }

  std::vector<std::string> args = cmSystemTools::ParseArguments(command);

  if(args.size() < 1)
    {
    return false;
    }
  return cmSystemTools::RunSingleCommand(args, captureStdOut, captureStdErr,
                                         retVal, dir, outputflag, timeout);
}

std::string
cmSystemTools::PrintSingleCommand(std::vector<std::string> const& command)
{
  if (command.empty())
    {
    return std::string();
    }

  return cmWrap('"', command, '"', " ");
}

bool cmSystemTools::DoesFileExistWithExtensions(
  const char* name,
  const std::vector<std::string>& headerExts)
{
  std::string hname;

  for( std::vector<std::string>::const_iterator ext = headerExts.begin();
       ext != headerExts.end(); ++ext )
    {
    hname = name;
    hname += ".";
    hname += *ext;
    if(cmSystemTools::FileExists(hname.c_str()))
      {
      return true;
      }
    }
  return false;
}

std::string cmSystemTools::FileExistsInParentDirectories(const char* fname,
  const char* directory, const char* toplevel)
{
  std::string file = fname;
  cmSystemTools::ConvertToUnixSlashes(file);
  std::string dir = directory;
  cmSystemTools::ConvertToUnixSlashes(dir);
  std::string prevDir;
  while(dir != prevDir)
    {
    std::string path = dir + "/" + file;
    if ( cmSystemTools::FileExists(path.c_str()) )
      {
      return path;
      }
    if ( dir.size() < strlen(toplevel) )
      {
      break;
      }
    prevDir = dir;
    dir = cmSystemTools::GetParentDirectory(dir);
    }
  return "";
}

bool cmSystemTools::cmCopyFile(const char* source, const char* destination)
{
  return Superclass::CopyFileAlways(source, destination);
}

bool cmSystemTools::CopyFileIfDifferent(const char* source,
  const char* destination)
{
  return Superclass::CopyFileIfDifferent(source, destination);
}

//----------------------------------------------------------------------------
#ifdef _WIN32
cmSystemTools::WindowsFileRetry cmSystemTools::GetWindowsFileRetry()
{
  static WindowsFileRetry retry = {0,0};
  if(!retry.Count)
    {
    unsigned int data[2] = {0,0};
    HKEY const keys[2] = {HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE};
    wchar_t const* const values[2] = {L"FilesystemRetryCount",
                                      L"FilesystemRetryDelay"};
    for(int k=0; k < 2; ++k)
      {
      HKEY hKey;
      if(RegOpenKeyExW(keys[k], L"Software\\Kitware\\CMake\\Config",
                       0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS)
        {
        for(int v=0; v < 2; ++v)
          {
          DWORD dwData, dwType, dwSize = 4;
          if(!data[v] &&
             RegQueryValueExW(hKey, values[v], 0, &dwType, (BYTE *)&dwData,
                              &dwSize) == ERROR_SUCCESS &&
             dwType == REG_DWORD && dwSize == 4)
            {
            data[v] = static_cast<unsigned int>(dwData);
            }
          }
        RegCloseKey(hKey);
        }
      }
    retry.Count = data[0]? data[0] : 5;
    retry.Delay = data[1]? data[1] : 500;
    }
  return retry;
}
#endif

//----------------------------------------------------------------------------
bool cmSystemTools::RenameFile(const char* oldname, const char* newname)
{
#ifdef _WIN32
# ifndef INVALID_FILE_ATTRIBUTES
#  define INVALID_FILE_ATTRIBUTES ((DWORD)-1)
# endif
  /* Windows MoveFileEx may not replace read-only or in-use files.  If it
     fails then remove the read-only attribute from any existing destination.
     Try multiple times since we may be racing against another process
     creating/opening the destination file just before our MoveFileEx.  */
  WindowsFileRetry retry = cmSystemTools::GetWindowsFileRetry();
  while(!MoveFileExW(cmsys::Encoding::ToWide(oldname).c_str(),
                     cmsys::Encoding::ToWide(newname).c_str(),
                     MOVEFILE_REPLACE_EXISTING) && --retry.Count)
    {
    DWORD last_error = GetLastError();
    // Try again only if failure was due to access/sharing permissions.
    if(last_error != ERROR_ACCESS_DENIED &&
       last_error != ERROR_SHARING_VIOLATION)
      {
      return false;
      }
    DWORD attrs =
      GetFileAttributesW(cmsys::Encoding::ToWide(newname).c_str());
    if((attrs != INVALID_FILE_ATTRIBUTES) &&
       (attrs & FILE_ATTRIBUTE_READONLY))
      {
      // Remove the read-only attribute from the destination file.
      SetFileAttributesW(cmsys::Encoding::ToWide(newname).c_str(),
                         attrs & ~FILE_ATTRIBUTE_READONLY);
      }
    else
      {
      // The file may be temporarily in use so wait a bit.
      cmSystemTools::Delay(retry.Delay);
      }
    }
  return retry.Count > 0;
#else
  /* On UNIX we have an OS-provided call to do this atomically.  */
  return rename(oldname, newname) == 0;
#endif
}

bool cmSystemTools::ComputeFileMD5(const std::string& source, char* md5out)
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  cmCryptoHashMD5 md5;
  std::string str = md5.HashFile(source);
  strncpy(md5out, str.c_str(), 32);
  return !str.empty();
#else
  (void)source;
  (void)md5out;
  cmSystemTools::Message("md5sum not supported in bootstrapping mode","Error");
  return false;
#endif
}

std::string cmSystemTools::ComputeStringMD5(const std::string& input)
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  cmCryptoHashMD5 md5;
  return md5.HashString(input);
#else
  (void)input;
  cmSystemTools::Message("md5sum not supported in bootstrapping mode","Error");
  return "";
#endif
}

void cmSystemTools::Glob(const std::string& directory,
                         const std::string& regexp,
                         std::vector<std::string>& files)
{
  cmsys::Directory d;
  cmsys::RegularExpression reg(regexp.c_str());

  if (d.Load(directory))
    {
    size_t numf;
        unsigned int i;
    numf = d.GetNumberOfFiles();
    for (i = 0; i < numf; i++)
      {
      std::string fname = d.GetFile(i);
      if (reg.find(fname))
        {
        files.push_back(fname);
        }
      }
    }
}


void cmSystemTools::GlobDirs(const std::string& path,
                             std::vector<std::string>& files)
{
  std::string::size_type pos = path.find("/*");
  if(pos == std::string::npos)
    {
    files.push_back(path);
    return;
    }
  std::string startPath = path.substr(0, pos);
  std::string finishPath = path.substr(pos+2);

  cmsys::Directory d;
  if (d.Load(startPath))
    {
    for (unsigned int i = 0; i < d.GetNumberOfFiles(); ++i)
      {
      if((std::string(d.GetFile(i)) != ".")
         && (std::string(d.GetFile(i)) != ".."))
        {
        std::string fname = startPath;
        fname +="/";
        fname += d.GetFile(i);
        if(cmSystemTools::FileIsDirectory(fname))
          {
          fname += finishPath;
          cmSystemTools::GlobDirs(fname, files);
          }
        }
      }
    }
}


void cmSystemTools::ExpandList(std::vector<std::string> const& arguments,
                               std::vector<std::string>& newargs)
{
  std::vector<std::string>::const_iterator i;
  for(i = arguments.begin();i != arguments.end(); ++i)
    {
    cmSystemTools::ExpandListArgument(*i, newargs);
    }
}

void cmSystemTools::ExpandListArgument(const std::string& arg,
                                       std::vector<std::string>& newargs,
                                       bool emptyArgs)
{
  // If argument is empty, it is an empty list.
  if(!emptyArgs && arg.empty())
    {
    return;
    }
  // if there are no ; in the name then just copy the current string
  if(arg.find(';') == std::string::npos)
    {
    newargs.push_back(arg);
    return;
    }
  std::string newArg;
  const char *last = arg.c_str();
  // Break the string at non-escaped semicolons not nested in [].
  int squareNesting = 0;
  for(const char* c = last; *c; ++c)
    {
    switch(*c)
      {
      case '\\':
        {
        // We only want to allow escaping of semicolons.  Other
        // escapes should not be processed here.
        const char* next = c + 1;
        if(*next == ';')
          {
          newArg.append(last, c - last);
          // Skip over the escape character
          last = c = next;
          }
        } break;
      case '[':
        {
        ++squareNesting;
        } break;
      case ']':
        {
        --squareNesting;
        } break;
      case ';':
        {
        // Break the string here if we are not nested inside square
        // brackets.
        if(squareNesting == 0)
          {
          newArg.append(last, c - last);
          // Skip over the semicolon
          last = c + 1;
          if ( !newArg.empty() || emptyArgs )
            {
            // Add the last argument if the string is not empty.
            newargs.push_back(newArg);
            newArg = "";
            }
          }
        } break;
      default:
        {
        // Just append this character.
        } break;
      }
    }
  newArg.append(last);
  if ( !newArg.empty() || emptyArgs )
    {
    // Add the last argument if the string is not empty.
    newargs.push_back(newArg);
    }
}

bool cmSystemTools::SimpleGlob(const std::string& glob,
                               std::vector<std::string>& files,
                               int type /* = 0 */)
{
  files.clear();
  if ( glob[glob.size()-1] != '*' )
    {
    return false;
    }
  std::string path = cmSystemTools::GetFilenamePath(glob);
  std::string ppath = cmSystemTools::GetFilenameName(glob);
  ppath = ppath.substr(0, ppath.size()-1);
  if (path.empty())
    {
    path = "/";
    }

  bool res = false;
  cmsys::Directory d;
  if (d.Load(path))
    {
    for (unsigned int i = 0; i < d.GetNumberOfFiles(); ++i)
      {
      if((std::string(d.GetFile(i)) != ".")
         && (std::string(d.GetFile(i)) != ".."))
        {
        std::string fname = path;
        if ( path[path.size()-1] != '/' )
          {
          fname +="/";
          }
        fname += d.GetFile(i);
        std::string sfname = d.GetFile(i);
        if ( type > 0 && cmSystemTools::FileIsDirectory(fname) )
          {
          continue;
          }
        if ( type < 0 && !cmSystemTools::FileIsDirectory(fname) )
          {
          continue;
          }
        if ( sfname.size() >= ppath.size() &&
             sfname.substr(0, ppath.size()) ==
             ppath )
          {
          files.push_back(fname);
          res = true;
          }
        }
      }
    }
  return res;
}

cmSystemTools::FileFormat cmSystemTools::GetFileFormat(const char* cext)
{
  if ( ! cext || *cext == 0 )
    {
    return cmSystemTools::NO_FILE_FORMAT;
    }
  //std::string ext = cmSystemTools::LowerCase(cext);
  std::string ext = cext;
  if ( ext == "c" || ext == ".c" ||
       ext == "m" || ext == ".m"
    ) { return cmSystemTools::C_FILE_FORMAT; }
  if (
    ext == "C" || ext == ".C" ||
    ext == "M" || ext == ".M" ||
    ext == "c++" || ext == ".c++" ||
    ext == "cc" || ext == ".cc" ||
    ext == "cpp" || ext == ".cpp" ||
    ext == "cxx" || ext == ".cxx" ||
    ext == "mm" || ext == ".mm"
    ) { return cmSystemTools::CXX_FILE_FORMAT; }
  if (
    ext == "f" || ext == ".f" ||
    ext == "F" || ext == ".F" ||
    ext == "f77" || ext == ".f77" ||
    ext == "f90" || ext == ".f90" ||
    ext == "for" || ext == ".for" ||
    ext == "f95" || ext == ".f95"
    ) { return cmSystemTools::FORTRAN_FILE_FORMAT; }
  if ( ext == "java" || ext == ".java" )
    { return cmSystemTools::JAVA_FILE_FORMAT; }
  if (
    ext == "H" || ext == ".H" ||
    ext == "h" || ext == ".h" ||
    ext == "h++" || ext == ".h++" ||
    ext == "hm" || ext == ".hm" ||
    ext == "hpp" || ext == ".hpp" ||
    ext == "hxx" || ext == ".hxx" ||
    ext == "in" || ext == ".in" ||
    ext == "txx" || ext == ".txx"
    ) { return cmSystemTools::HEADER_FILE_FORMAT; }
  if ( ext == "rc" || ext == ".rc" )
    { return cmSystemTools::RESOURCE_FILE_FORMAT; }
  if ( ext == "def" || ext == ".def" )
    { return cmSystemTools::DEFINITION_FILE_FORMAT; }
  if ( ext == "lib" || ext == ".lib" ||
       ext == "a" || ext == ".a")
    { return cmSystemTools::STATIC_LIBRARY_FILE_FORMAT; }
  if ( ext == "o" || ext == ".o" ||
       ext == "obj" || ext == ".obj")
    { return cmSystemTools::OBJECT_FILE_FORMAT; }
#ifdef __APPLE__
  if ( ext == "dylib" || ext == ".dylib" )
    { return cmSystemTools::SHARED_LIBRARY_FILE_FORMAT; }
  if ( ext == "so" || ext == ".so" ||
       ext == "bundle" || ext == ".bundle" )
    { return cmSystemTools::MODULE_FILE_FORMAT; }
#else // __APPLE__
  if ( ext == "so" || ext == ".so" ||
       ext == "sl" || ext == ".sl" ||
       ext == "dll" || ext == ".dll" )
    { return cmSystemTools::SHARED_LIBRARY_FILE_FORMAT; }
#endif // __APPLE__
  return cmSystemTools::UNKNOWN_FILE_FORMAT;
}

bool cmSystemTools::Split(const char* s, std::vector<std::string>& l)
{
  std::vector<std::string> temp;
  bool res = Superclass::Split(s, temp);
  l.insert(l.end(), temp.begin(), temp.end());
  return res;
}

std::string cmSystemTools::ConvertToOutputPath(const char* path)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  if(s_ForceUnixPaths)
    {
    return cmSystemTools::ConvertToUnixOutputPath(path);
    }
  return cmSystemTools::ConvertToWindowsOutputPath(path);
#else
  return cmSystemTools::ConvertToUnixOutputPath(path);
#endif
}

void cmSystemTools::ConvertToOutputSlashes(std::string& path)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  if(!s_ForceUnixPaths)
    {
    // Convert to windows slashes.
    std::string::size_type pos = 0;
    while((pos = path.find('/', pos)) != std::string::npos)
      {
      path[pos++] = '\\';
      }
    }
#else
  static_cast<void>(path);
#endif
}

std::string cmSystemTools::ConvertToRunCommandPath(const char* path)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  return cmSystemTools::ConvertToWindowsOutputPath(path);
#else
  return cmSystemTools::ConvertToUnixOutputPath(path);
#endif
}

bool cmSystemTools::StringEndsWith(const char* str1, const char* str2)
{
  if ( !str1 || !str2 || strlen(str1) < strlen(str2) )
    {
    return 0;
    }
  return !strncmp(str1 + (strlen(str1)-strlen(str2)), str2, strlen(str2));
}

// compute the relative path from here to there
std::string cmSystemTools::RelativePath(const char* local, const char* remote)
{
  if(!cmSystemTools::FileIsFullPath(local))
    {
    cmSystemTools::Error("RelativePath must be passed a full path to local: ",
                         local);
    }
  if(!cmSystemTools::FileIsFullPath(remote))
    {
    cmSystemTools::Error
      ("RelativePath must be passed a full path to remote: ", remote);
    }
  return cmsys::SystemTools::RelativePath(local, remote);
}

std::string cmSystemTools::CollapseCombinedPath(std::string const& dir,
                                                std::string const& file)
{
  if(dir.empty() || dir == ".")
    {
    return file;
    }

  std::vector<std::string> dirComponents;
  std::vector<std::string> fileComponents;
  cmSystemTools::SplitPath(dir, dirComponents);
  cmSystemTools::SplitPath(file, fileComponents);

  if(fileComponents.empty())
    {
    return dir;
    }
  if(fileComponents[0] != "")
    {
    // File is not a relative path.
    return file;
    }

  std::vector<std::string>::iterator i = fileComponents.begin()+1;
  while(i != fileComponents.end() && *i == ".." && dirComponents.size() > 1)
    {
    ++i; // Remove ".." file component.
    dirComponents.pop_back(); // Remove last dir component.
    }

  dirComponents.insert(dirComponents.end(), i, fileComponents.end());
  return cmSystemTools::JoinPath(dirComponents);
}

#ifdef CMAKE_BUILD_WITH_CMAKE
//----------------------------------------------------------------------
bool cmSystemTools::UnsetEnv(const char* value)
{
#if !defined(HAVE_UNSETENV)
  std::string var = value;
  var += "=";
  return cmSystemTools::PutEnv(var.c_str());
#else
  unsetenv(value);
  return true;
#endif
}

//----------------------------------------------------------------------
std::vector<std::string> cmSystemTools::GetEnvironmentVariables()
{
  std::vector<std::string> env;
  int cc;
  for ( cc = 0; environ[cc]; ++ cc )
    {
    env.push_back(environ[cc]);
    }
  return env;
}

//----------------------------------------------------------------------
void cmSystemTools::AppendEnv(std::vector<std::string> const& env)
{
  for(std::vector<std::string>::const_iterator eit = env.begin();
      eit != env.end(); ++eit)
    {
    cmSystemTools::PutEnv(*eit);
    }
}

//----------------------------------------------------------------------
cmSystemTools::SaveRestoreEnvironment::SaveRestoreEnvironment()
{
  this->Env = cmSystemTools::GetEnvironmentVariables();
}

//----------------------------------------------------------------------
cmSystemTools::SaveRestoreEnvironment::~SaveRestoreEnvironment()
{
  // First clear everything in the current environment:
  std::vector<std::string> currentEnv = GetEnvironmentVariables();
  for(std::vector<std::string>::const_iterator
        eit = currentEnv.begin(); eit != currentEnv.end(); ++eit)
    {
    std::string var(*eit);

    std::string::size_type pos = var.find("=");
    if (pos != std::string::npos)
      {
      var = var.substr(0, pos);
      }

    cmSystemTools::UnsetEnv(var.c_str());
    }

  // Then put back each entry from the original environment:
  cmSystemTools::AppendEnv(this->Env);
}
#endif

void cmSystemTools::EnableVSConsoleOutput()
{
#ifdef _WIN32
  // Visual Studio 8 2005 (devenv.exe or VCExpress.exe) will not
  // display output to the console unless this environment variable is
  // set.  We need it to capture the output of these build tools.
  // Note for future work that one could pass "/out \\.\pipe\NAME" to
  // either of these executables where NAME is created with
  // CreateNamedPipe.  This would bypass the internal buffering of the
  // output and allow it to be captured on the fly.
  cmSystemTools::PutEnv("vsconsoleoutput=1");

# ifdef CMAKE_BUILD_WITH_CMAKE
  // VS sets an environment variable to tell MS tools like "cl" to report
  // output through a backdoor pipe instead of stdout/stderr.  Unset the
  // environment variable to close this backdoor for any path of process
  // invocations that passes through CMake so we can capture the output.
  cmSystemTools::UnsetEnv("VS_UNICODE_OUTPUT");
# endif
#endif
}

bool cmSystemTools::IsPathToFramework(const char* path)
{
  return (cmSystemTools::FileIsFullPath(path) &&
          cmHasLiteralSuffix(path, ".framework"));
}

bool cmSystemTools::CreateTar(const char* outFileName,
                              const std::vector<std::string>& files,
                              cmTarCompression compressType,
                              bool verbose, std::string const& mtime,
                              std::string const& format)
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  std::string cwd = cmSystemTools::GetCurrentWorkingDirectory();
  cmsys::ofstream fout(outFileName, std::ios::out | cmsys_ios_binary);
  if(!fout)
    {
    std::string e = "Cannot open output file \"";
    e += outFileName;
    e += "\": ";
    e += cmSystemTools::GetLastSystemError();
    cmSystemTools::Error(e.c_str());
    return false;
    }
  cmArchiveWrite::Compress compress = cmArchiveWrite::CompressNone;
  switch (compressType)
    {
    case TarCompressGZip:
      compress = cmArchiveWrite::CompressGZip;
      break;
    case TarCompressBZip2:
      compress = cmArchiveWrite::CompressBZip2;
      break;
    case TarCompressXZ:
      compress = cmArchiveWrite::CompressXZ;
      break;
    case TarCompressNone:
      compress = cmArchiveWrite::CompressNone;
      break;
    }

  cmArchiveWrite a(fout, compress,
    format.empty() ? "paxr" : format);

  a.SetMTime(mtime);
  a.SetVerbose(verbose);
  for(std::vector<std::string>::const_iterator i = files.begin();
      i != files.end(); ++i)
    {
    std::string path = *i;
    if(cmSystemTools::FileIsFullPath(path.c_str()))
      {
      // Get the relative path to the file.
      path = cmSystemTools::RelativePath(cwd.c_str(), path.c_str());
      }
    if(!a.Add(path))
      {
      break;
      }
    }
  if(!a)
    {
    cmSystemTools::Error(a.GetError().c_str());
    return false;
    }
  return true;
#else
  (void)outFileName;
  (void)files;
  (void)verbose;
  return false;
#endif
}

#if defined(CMAKE_BUILD_WITH_CMAKE)
namespace{
#define BSDTAR_FILESIZE_PRINTF  "%lu"
#define BSDTAR_FILESIZE_TYPE    unsigned long
  void
    list_item_verbose(FILE *out, struct archive_entry *entry)
{
  char                   tmp[100];
  size_t                         w;
  const char            *p;
  const char            *fmt;
  time_t                         tim;
  static time_t          now;
  size_t u_width = 6;
  size_t gs_width = 13;

  /*
   * We avoid collecting the entire list in memory at once by
   * listing things as we see them.  However, that also means we can't
   * just pre-compute the field widths.  Instead, we start with guesses
   * and just widen them as necessary.  These numbers are completely
   * arbitrary.
   */
  if (!now)
    {
    time(&now);
    }
  fprintf(out, "%s %d ",
          archive_entry_strmode(entry),
          archive_entry_nlink(entry));

  /* Use uname if it's present, else uid. */
  p = archive_entry_uname(entry);
  if ((p == NULL) || (*p == '\0'))
    {
    sprintf(tmp, "%lu ",
            (unsigned long)archive_entry_uid(entry));
    p = tmp;
    }
  w = strlen(p);
  if (w > u_width)
    {
    u_width = w;
    }
  fprintf(out, "%-*s ", (int)u_width, p);
  /* Use gname if it's present, else gid. */
  p = archive_entry_gname(entry);
  if (p != NULL && p[0] != '\0')
    {
    fprintf(out, "%s", p);
    w = strlen(p);
    }
  else
    {
    sprintf(tmp, "%lu",
            (unsigned long)archive_entry_gid(entry));
    w = strlen(tmp);
    fprintf(out, "%s", tmp);
    }

  /*
   * Print device number or file size, right-aligned so as to make
   * total width of group and devnum/filesize fields be gs_width.
   * If gs_width is too small, grow it.
   */
  if (archive_entry_filetype(entry) == AE_IFCHR
      || archive_entry_filetype(entry) == AE_IFBLK)
    {
    sprintf(tmp, "%lu,%lu",
            (unsigned long)archive_entry_rdevmajor(entry),
            (unsigned long)archive_entry_rdevminor(entry));
    }
  else
    {
    /*
     * Note the use of platform-dependent macros to format
     * the filesize here.  We need the format string and the
     * corresponding type for the cast.
     */
    sprintf(tmp, BSDTAR_FILESIZE_PRINTF,
            (BSDTAR_FILESIZE_TYPE)archive_entry_size(entry));
    }
  if (w + strlen(tmp) >= gs_width)
    {
    gs_width = w+strlen(tmp)+1;
    }
  fprintf(out, "%*s", (int)(gs_width - w), tmp);

  /* Format the time using 'ls -l' conventions. */
  tim = archive_entry_mtime(entry);
#define HALF_YEAR (time_t)365 * 86400 / 2
#if defined(_WIN32) && !defined(__CYGWIN__)
  /* Windows' strftime function does not support %e format. */
#define DAY_FMT  "%d"
#else
#define DAY_FMT  "%e"  /* Day number without leading zeros */
#endif
  if (tim < now - HALF_YEAR || tim > now + HALF_YEAR)
    {
    fmt = DAY_FMT " %b  %Y";
    }
  else
    {
    fmt = DAY_FMT " %b %H:%M";
    }
  strftime(tmp, sizeof(tmp), fmt, localtime(&tim));
  fprintf(out, " %s ", tmp);
  fprintf(out, "%s", cm_archive_entry_pathname(entry).c_str());

  /* Extra information for links. */
  if (archive_entry_hardlink(entry)) /* Hard link */
    {
    fprintf(out, " link to %s",
            archive_entry_hardlink(entry));
    }
  else if (archive_entry_symlink(entry)) /* Symbolic link */
    {
    fprintf(out, " -> %s", archive_entry_symlink(entry));
    }
}

long copy_data(struct archive *ar, struct archive *aw)
{
  long r;
  const void *buff;
  size_t size;
#if defined(ARCHIVE_VERSION_NUMBER) && ARCHIVE_VERSION_NUMBER >= 3000000
  __LA_INT64_T offset;
#else
  off_t offset;
#endif

  for (;;)
    {
    r = archive_read_data_block(ar, &buff, &size, &offset);
    if (r == ARCHIVE_EOF)
      {
      return (ARCHIVE_OK);
      }
    if (r != ARCHIVE_OK)
      {
      return (r);
      }
    r = archive_write_data_block(aw, buff, size, offset);
    if (r != ARCHIVE_OK)
      {
      cmSystemTools::Message("archive_write_data_block()",
                             archive_error_string(aw));
      return (r);
      }
    }
#if !defined(__clang__) && !defined(__HP_aCC)
  return r; /* this should not happen but it quiets some compilers */
#endif
}

bool extract_tar(const char* outFileName, bool verbose,
                 bool extract)
{
  cmLocaleRAII localeRAII;
  static_cast<void>(localeRAII);
  struct archive* a = archive_read_new();
  struct archive *ext = archive_write_disk_new();
  archive_read_support_compression_all(a);
  archive_read_support_format_all(a);
  struct archive_entry *entry;
  int r = cm_archive_read_open_file(a, outFileName, 10240);
  if(r)
    {
    cmSystemTools::Error("Problem with archive_read_open_file(): ",
                         archive_error_string(a));
    archive_write_free(ext);
    archive_read_close(a);
    return false;
    }
  for (;;)
    {
    r = archive_read_next_header(a, &entry);
    if (r == ARCHIVE_EOF)
      {
      break;
      }
    if (r != ARCHIVE_OK)
      {
      cmSystemTools::Error("Problem with archive_read_next_header(): ",
                           archive_error_string(a));
      break;
      }
    if(verbose)
      {
      if(extract)
        {
        cmSystemTools::Stdout("x ");
        cmSystemTools::Stdout(cm_archive_entry_pathname(entry).c_str());
        }
      else
        {
        list_item_verbose(stdout, entry);
        }
      cmSystemTools::Stdout("\n");
      }
    else if(!extract)
      {
      cmSystemTools::Stdout(cm_archive_entry_pathname(entry).c_str());
      cmSystemTools::Stdout("\n");
      }
    if(extract)
      {
      r = archive_write_disk_set_options(ext, ARCHIVE_EXTRACT_TIME);
      if (r != ARCHIVE_OK)
        {
        cmSystemTools::Error(
          "Problem with archive_write_disk_set_options(): ",
          archive_error_string(ext));
        break;
        }

      r = archive_write_header(ext, entry);
      if (r == ARCHIVE_OK)
        {
        copy_data(a, ext);
        r = archive_write_finish_entry(ext);
        if (r != ARCHIVE_OK)
          {
          cmSystemTools::Error("Problem with archive_write_finish_entry(): ",
                               archive_error_string(ext));
          break;
          }
        }
#ifdef _WIN32
      else if(const char* linktext = archive_entry_symlink(entry))
        {
        std::cerr << "cmake -E tar: warning: skipping symbolic link \""
                  << cm_archive_entry_pathname(entry)
                  << "\" -> \""
                  << linktext << "\"." << std::endl;
        }
#endif
      else
        {
        cmSystemTools::Error("Problem with archive_write_header(): ",
                             archive_error_string(ext));
        cmSystemTools::Error("Current file: ",
                             cm_archive_entry_pathname(entry).c_str());
        break;
        }
      }
    }
  archive_write_free(ext);
  archive_read_close(a);
  archive_read_finish(a);
  return r == ARCHIVE_EOF || r == ARCHIVE_OK;
}
}
#endif

bool cmSystemTools::ExtractTar(const char* outFileName,
                               bool verbose)
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  return extract_tar(outFileName, verbose, true);
#else
  (void)outFileName;
  (void)verbose;
  return false;
#endif
}

bool cmSystemTools::ListTar(const char* outFileName,
                            bool verbose)
{
#if defined(CMAKE_BUILD_WITH_CMAKE)
  return extract_tar(outFileName, verbose, false);
#else
  (void)outFileName;
  (void)verbose;
  return false;
#endif
}

int cmSystemTools::WaitForLine(cmsysProcess* process, std::string& line,
                               double timeout,
                               std::vector<char>& out,
                               std::vector<char>& err)
{
  line = "";
  std::vector<char>::iterator outiter = out.begin();
  std::vector<char>::iterator erriter = err.begin();
  while(1)
    {
    // Check for a newline in stdout.
    for(;outiter != out.end(); ++outiter)
      {
      if((*outiter == '\r') && ((outiter+1) == out.end()))
        {
        break;
        }
      else if(*outiter == '\n' || *outiter == '\0')
        {
        std::vector<char>::size_type length = outiter-out.begin();
        if(length > 1 && *(outiter-1) == '\r')
          {
          --length;
          }
        if(length > 0)
          {
          line.append(&out[0], length);
          }
        out.erase(out.begin(), outiter+1);
        return cmsysProcess_Pipe_STDOUT;
        }
      }

    // Check for a newline in stderr.
    for(;erriter != err.end(); ++erriter)
      {
      if((*erriter == '\r') && ((erriter+1) == err.end()))
        {
        break;
        }
      else if(*erriter == '\n' || *erriter == '\0')
        {
        std::vector<char>::size_type length = erriter-err.begin();
        if(length > 1 && *(erriter-1) == '\r')
          {
          --length;
          }
        if(length > 0)
          {
          line.append(&err[0], length);
          }
        err.erase(err.begin(), erriter+1);
        return cmsysProcess_Pipe_STDERR;
        }
      }

    // No newlines found.  Wait for more data from the process.
    int length;
    char* data;
    int pipe = cmsysProcess_WaitForData(process, &data, &length, &timeout);
    if(pipe == cmsysProcess_Pipe_Timeout)
      {
      // Timeout has been exceeded.
      return pipe;
      }
    else if(pipe == cmsysProcess_Pipe_STDOUT)
      {
      // Append to the stdout buffer.
      std::vector<char>::size_type size = out.size();
      out.insert(out.end(), data, data+length);
      outiter = out.begin()+size;
      }
    else if(pipe == cmsysProcess_Pipe_STDERR)
      {
      // Append to the stderr buffer.
      std::vector<char>::size_type size = err.size();
      err.insert(err.end(), data, data+length);
      erriter = err.begin()+size;
      }
    else if(pipe == cmsysProcess_Pipe_None)
      {
      // Both stdout and stderr pipes have broken.  Return leftover data.
      if(!out.empty())
        {
        line.append(&out[0], outiter-out.begin());
        out.erase(out.begin(), out.end());
        return cmsysProcess_Pipe_STDOUT;
        }
      else if(!err.empty())
        {
        line.append(&err[0], erriter-err.begin());
        err.erase(err.begin(), err.end());
        return cmsysProcess_Pipe_STDERR;
        }
      else
        {
        return cmsysProcess_Pipe_None;
        }
      }
    }
}

void cmSystemTools::DoNotInheritStdPipes()
{
#ifdef _WIN32
  // Check to see if we are attached to a console
  // if so, then do not stop the inherited pipes
  // or stdout and stderr will not show up in dos
  // shell windows
  CONSOLE_SCREEN_BUFFER_INFO hOutInfo;
  HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
  if(GetConsoleScreenBufferInfo(hOut, &hOutInfo))
    {
    return;
    }
  {
  HANDLE out = GetStdHandle(STD_OUTPUT_HANDLE);
  DuplicateHandle(GetCurrentProcess(), out,
                  GetCurrentProcess(), &out, 0, FALSE,
                  DUPLICATE_SAME_ACCESS | DUPLICATE_CLOSE_SOURCE);
  SetStdHandle(STD_OUTPUT_HANDLE, out);
  }
  {
  HANDLE out = GetStdHandle(STD_ERROR_HANDLE);
  DuplicateHandle(GetCurrentProcess(), out,
                  GetCurrentProcess(), &out, 0, FALSE,
                  DUPLICATE_SAME_ACCESS | DUPLICATE_CLOSE_SOURCE);
  SetStdHandle(STD_ERROR_HANDLE, out);
  }
#endif
}

//----------------------------------------------------------------------------
bool cmSystemTools::CopyFileTime(const char* fromFile, const char* toFile)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  cmSystemToolsWindowsHandle hFrom =
    CreateFileW(cmsys::Encoding::ToWide(fromFile).c_str(),
                GENERIC_READ, FILE_SHARE_READ, 0,
                OPEN_EXISTING, 0, 0);
  cmSystemToolsWindowsHandle hTo =
    CreateFileW(cmsys::Encoding::ToWide(toFile).c_str(),
                GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
  if(!hFrom || !hTo)
    {
    return false;
    }
  FILETIME timeCreation;
  FILETIME timeLastAccess;
  FILETIME timeLastWrite;
  if(!GetFileTime(hFrom, &timeCreation, &timeLastAccess, &timeLastWrite))
    {
    return false;
    }
  if(!SetFileTime(hTo, &timeCreation, &timeLastAccess, &timeLastWrite))
    {
    return false;
    }
#else
  struct stat fromStat;
  if(stat(fromFile, &fromStat) < 0)
    {
    return false;
    }

  struct utimbuf buf;
  buf.actime = fromStat.st_atime;
  buf.modtime = fromStat.st_mtime;
  if(utime(toFile, &buf) < 0)
    {
    return false;
    }
#endif
  return true;
}

//----------------------------------------------------------------------------
cmSystemToolsFileTime* cmSystemTools::FileTimeNew()
{
  return new cmSystemToolsFileTime;
}

//----------------------------------------------------------------------------
void cmSystemTools::FileTimeDelete(cmSystemToolsFileTime* t)
{
  delete t;
}

//----------------------------------------------------------------------------
bool cmSystemTools::FileTimeGet(const char* fname, cmSystemToolsFileTime* t)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  cmSystemToolsWindowsHandle h =
    CreateFileW(cmsys::Encoding::ToWide(fname).c_str(),
                GENERIC_READ, FILE_SHARE_READ, 0, OPEN_EXISTING, 0, 0);
  if(!h)
    {
    return false;
    }
  if(!GetFileTime(h, &t->timeCreation, &t->timeLastAccess, &t->timeLastWrite))
    {
    return false;
    }
#else
  struct stat st;
  if(stat(fname, &st) < 0)
    {
    return false;
    }
  t->timeBuf.actime = st.st_atime;
  t->timeBuf.modtime = st.st_mtime;
#endif
  return true;
}

//----------------------------------------------------------------------------
bool cmSystemTools::FileTimeSet(const char* fname, cmSystemToolsFileTime* t)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  cmSystemToolsWindowsHandle h =
    CreateFileW(cmsys::Encoding::ToWide(fname).c_str(),
                GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
  if(!h)
    {
    return false;
    }
  if(!SetFileTime(h, &t->timeCreation, &t->timeLastAccess, &t->timeLastWrite))
    {
    return false;
    }
#else
  if(utime(fname, &t->timeBuf) < 0)
    {
    return false;
    }
#endif
  return true;
}

//----------------------------------------------------------------------------
#ifdef _WIN32
# ifndef CRYPT_SILENT
#  define CRYPT_SILENT 0x40 /* Not defined by VS 6 version of header.  */
# endif
static int WinCryptRandom(void* data, size_t size)
{
  int result = 0;
  HCRYPTPROV hProvider = 0;
  if(CryptAcquireContextW(&hProvider, 0, 0, PROV_RSA_FULL,
                          CRYPT_VERIFYCONTEXT | CRYPT_SILENT))
    {
    result = CryptGenRandom(hProvider, (DWORD)size, (BYTE*)data)? 1:0;
    CryptReleaseContext(hProvider, 0);
    }
  return result;
}
#endif

//----------------------------------------------------------------------------
unsigned int cmSystemTools::RandomSeed()
{
#if defined(_WIN32) && !defined(__CYGWIN__)
  unsigned int seed = 0;

  // Try using a real random source.
  if(WinCryptRandom(&seed, sizeof(seed)))
    {
    return seed;
    }

  // Fall back to the time and pid.
  FILETIME ft;
  GetSystemTimeAsFileTime(&ft);
  unsigned int t1 = static_cast<unsigned int>(ft.dwHighDateTime);
  unsigned int t2 = static_cast<unsigned int>(ft.dwLowDateTime);
  unsigned int pid = static_cast<unsigned int>(GetCurrentProcessId());
  return t1 ^ t2 ^ pid;
#else
  union
  {
    unsigned int integer;
    char bytes[sizeof(unsigned int)];
  } seed;

  // Try using a real random source.
  cmsys::ifstream fin("/dev/urandom");
  if(fin && fin.read(seed.bytes, sizeof(seed)) &&
     fin.gcount() == sizeof(seed))
    {
    return seed.integer;
    }

  // Fall back to the time and pid.
  struct timeval t;
  gettimeofday(&t, 0);
  unsigned int pid = static_cast<unsigned int>(getpid());
  unsigned int tv_sec = static_cast<unsigned int>(t.tv_sec);
  unsigned int tv_usec = static_cast<unsigned int>(t.tv_usec);
  // Since tv_usec never fills more than 11 bits we shift it to fill
  // in the slow-changing high-order bits of tv_sec.
  return tv_sec ^ (tv_usec << 21) ^ pid;
#endif
}

//----------------------------------------------------------------------------
static std::string cmSystemToolsCMakeCommand;
static std::string cmSystemToolsCTestCommand;
static std::string cmSystemToolsCPackCommand;
static std::string cmSystemToolsCMakeCursesCommand;
static std::string cmSystemToolsCMakeGUICommand;
static std::string cmSystemToolsCMakeRoot;
void cmSystemTools::FindCMakeResources(const char* argv0)
{
  std::string exe_dir;
#if defined(_WIN32) && !defined(__CYGWIN__)
  (void)argv0; // ignore this on windows
  wchar_t modulepath[_MAX_PATH];
  ::GetModuleFileNameW(NULL, modulepath, sizeof(modulepath));
  exe_dir =
    cmSystemTools::GetFilenamePath(cmsys::Encoding::ToNarrow(modulepath));
#elif defined(__APPLE__)
  (void)argv0; // ignore this on OS X
# define CM_EXE_PATH_LOCAL_SIZE 16384
  char exe_path_local[CM_EXE_PATH_LOCAL_SIZE];
# if defined(MAC_OS_X_VERSION_10_3) && !defined(MAC_OS_X_VERSION_10_4)
  unsigned long exe_path_size = CM_EXE_PATH_LOCAL_SIZE;
# else
  uint32_t exe_path_size = CM_EXE_PATH_LOCAL_SIZE;
# endif
# undef CM_EXE_PATH_LOCAL_SIZE
  char* exe_path = exe_path_local;
  if(_NSGetExecutablePath(exe_path, &exe_path_size) < 0)
    {
    exe_path = (char*)malloc(exe_path_size);
    _NSGetExecutablePath(exe_path, &exe_path_size);
    }
  exe_dir =
    cmSystemTools::GetFilenamePath(
      cmSystemTools::GetRealPath(exe_path));
  if(exe_path != exe_path_local)
    {
    free(exe_path);
    }
  if(cmSystemTools::GetFilenameName(exe_dir) == "MacOS")
    {
    // The executable is inside an application bundle.
    // Look for ../bin (install tree) and then fall back to
    // ../../../bin (build tree).
    exe_dir = cmSystemTools::GetFilenamePath(exe_dir);
    if(cmSystemTools::FileExists((exe_dir+"/bin/cmake").c_str()))
      {
      exe_dir += "/bin";
      }
    else
      {
      exe_dir = cmSystemTools::GetFilenamePath(exe_dir);
      exe_dir = cmSystemTools::GetFilenamePath(exe_dir);
      }
    }
#else
  std::string errorMsg;
  std::string exe;
  if(cmSystemTools::FindProgramPath(argv0, exe, errorMsg))
    {
    // remove symlinks
    exe = cmSystemTools::GetRealPath(exe);
    exe_dir =
      cmSystemTools::GetFilenamePath(exe);
    }
  else
    {
    // ???
    }
#endif
  cmSystemToolsCMakeCommand = exe_dir;
  cmSystemToolsCMakeCommand += "/cmake";
  cmSystemToolsCMakeCommand += cmSystemTools::GetExecutableExtension();
#ifndef CMAKE_BUILD_WITH_CMAKE
  // The bootstrap cmake does not provide the other tools,
  // so use the directory where they are about to be built.
  exe_dir = CMAKE_BOOTSTRAP_BINARY_DIR "/bin";
#endif
  cmSystemToolsCTestCommand = exe_dir;
  cmSystemToolsCTestCommand += "/ctest";
  cmSystemToolsCTestCommand += cmSystemTools::GetExecutableExtension();
  cmSystemToolsCPackCommand = exe_dir;
  cmSystemToolsCPackCommand += "/cpack";
  cmSystemToolsCPackCommand += cmSystemTools::GetExecutableExtension();
  cmSystemToolsCMakeGUICommand = exe_dir;
  cmSystemToolsCMakeGUICommand += "/cmake-gui";
  cmSystemToolsCMakeGUICommand += cmSystemTools::GetExecutableExtension();
  if(!cmSystemTools::FileExists(cmSystemToolsCMakeGUICommand.c_str()))
    {
    cmSystemToolsCMakeGUICommand = "";
    }
  cmSystemToolsCMakeCursesCommand = exe_dir;
  cmSystemToolsCMakeCursesCommand += "/ccmake";
  cmSystemToolsCMakeCursesCommand += cmSystemTools::GetExecutableExtension();
  if(!cmSystemTools::FileExists(cmSystemToolsCMakeCursesCommand.c_str()))
    {
    cmSystemToolsCMakeCursesCommand = "";
    }

#ifdef CMAKE_BUILD_WITH_CMAKE
  // Install tree has "<prefix>/bin/cmake" and "<prefix><CMAKE_DATA_DIR>".
  std::string dir = cmSystemTools::GetFilenamePath(exe_dir);
  cmSystemToolsCMakeRoot = dir + CMAKE_DATA_DIR;
  if(!cmSystemTools::FileExists(
       (cmSystemToolsCMakeRoot+"/Modules/CMake.cmake").c_str()))
    {
    // Build tree has "<build>/bin[/<config>]/cmake" and
    // "<build>/CMakeFiles/CMakeSourceDir.txt".
    std::string src_dir_txt = dir + "/CMakeFiles/CMakeSourceDir.txt";
    cmsys::ifstream fin(src_dir_txt.c_str());
    std::string src_dir;
    if(fin && cmSystemTools::GetLineFromStream(fin, src_dir) &&
       cmSystemTools::FileIsDirectory(src_dir))
      {
      cmSystemToolsCMakeRoot = src_dir;
      }
    else
      {
      dir = cmSystemTools::GetFilenamePath(dir);
      src_dir_txt = dir + "/CMakeFiles/CMakeSourceDir.txt";
      cmsys::ifstream fin2(src_dir_txt.c_str());
      if(fin2 && cmSystemTools::GetLineFromStream(fin2, src_dir) &&
         cmSystemTools::FileIsDirectory(src_dir))
        {
        cmSystemToolsCMakeRoot = src_dir;
        }
      }
    }
#else
  // Bootstrap build knows its source.
  cmSystemToolsCMakeRoot = CMAKE_BOOTSTRAP_SOURCE_DIR;
#endif
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCMakeCommand()
{
  return cmSystemToolsCMakeCommand;
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCTestCommand()
{
  return cmSystemToolsCTestCommand;
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCPackCommand()
{
  return cmSystemToolsCPackCommand;
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCMakeCursesCommand()
{
  return cmSystemToolsCMakeCursesCommand;
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCMakeGUICommand()
{
  return cmSystemToolsCMakeGUICommand;
}

//----------------------------------------------------------------------------
std::string const& cmSystemTools::GetCMakeRoot()
{
  return cmSystemToolsCMakeRoot;
}

//----------------------------------------------------------------------------
void cmSystemTools::MakefileColorEcho(int color, const char* message,
                                      bool newline, bool enabled)
{
  // On some platforms (an MSYS prompt) cmsysTerminal may not be able
  // to determine whether the stream is displayed on a tty.  In this
  // case it assumes no unless we tell it otherwise.  Since we want
  // color messages to be displayed for users we will assume yes.
  // However, we can test for some situations when the answer is most
  // likely no.
  int assumeTTY = cmsysTerminal_Color_AssumeTTY;
  if(cmSystemTools::GetEnv("DART_TEST_FROM_DART") ||
     cmSystemTools::GetEnv("DASHBOARD_TEST_FROM_CTEST") ||
     cmSystemTools::GetEnv("CTEST_INTERACTIVE_DEBUG_MODE"))
    {
    // Avoid printing color escapes during dashboard builds.
    assumeTTY = 0;
    }

  if(enabled && color != cmsysTerminal_Color_Normal)
    {
    // Print with color.  Delay the newline until later so that
    // all color restore sequences appear before it.
    cmsysTerminal_cfprintf(color | assumeTTY, stdout, "%s", message);
    }
  else
    {
    // Color is disabled.  Print without color.
    fprintf(stdout, "%s", message);
    }

  if(newline)
    {
    fprintf(stdout, "\n");
    }
}

//----------------------------------------------------------------------------
bool cmSystemTools::GuessLibrarySOName(std::string const& fullPath,
                                       std::string& soname)
{
  // For ELF shared libraries use a real parser to get the correct
  // soname.
#if defined(CMAKE_USE_ELF_PARSER)
  cmELF elf(fullPath.c_str());
  if(elf)
    {
    return elf.GetSOName(soname);
    }
#endif

  // If the file is not a symlink we have no guess for its soname.
  if(!cmSystemTools::FileIsSymlink(fullPath))
    {
    return false;
    }
  if(!cmSystemTools::ReadSymlink(fullPath, soname))
    {
    return false;
    }

  // If the symlink has a path component we have no guess for the soname.
  if(!cmSystemTools::GetFilenamePath(soname).empty())
    {
    return false;
    }

  // If the symlink points at an extended version of the same name
  // assume it is the soname.
  std::string name = cmSystemTools::GetFilenameName(fullPath);
  if(soname.length() > name.length() &&
     soname.substr(0, name.length()) == name)
    {
    return true;
    }
  return false;
}

//----------------------------------------------------------------------------
bool cmSystemTools::GuessLibraryInstallName(std::string const& fullPath,
                                       std::string& soname)
{
#if defined(CMAKE_USE_MACH_PARSER)
  cmMachO macho(fullPath.c_str());
  if(macho)
    {
    return macho.GetInstallName(soname);
    }
#else
  (void)fullPath;
  (void)soname;
#endif

  return false;
}

//----------------------------------------------------------------------------
#if defined(CMAKE_USE_ELF_PARSER)
std::string::size_type cmSystemToolsFindRPath(std::string const& have,
                                              std::string const& want)
{
  // Search for the desired rpath.
  std::string::size_type pos = have.find(want);

  // If the path is not present we are done.
  if(pos == std::string::npos)
    {
    return pos;
    }

  // Build a regex to match a properly separated path instance.
  std::string regex_str = "(^|:)(";
  for(std::string::const_iterator i = want.begin(); i != want.end(); ++i)
    {
    int ch = *i;
    if(!(('a' <= ch && ch <= 'z') ||
         ('A' <= ch && ch <= 'Z') ||
         ('0' <= ch && ch <= '9')))
      {
      // Escape the non-alphanumeric character.
      regex_str += "\\";
      }
    // Store the character.
    regex_str.append(1, static_cast<char>(ch));
    }
  regex_str += ")(:|$)";

  // Look for the separated path.
  cmsys::RegularExpression regex(regex_str.c_str());
  if(regex.find(have))
    {
    // Return the position of the path portion.
    return regex.start(2);
    }
  else
    {
    // The desired rpath was not found.
    return std::string::npos;
    }
}
#endif

#if defined(CMAKE_USE_ELF_PARSER)
struct cmSystemToolsRPathInfo
{
  unsigned long Position;
  unsigned long Size;
  std::string Name;
  std::string Value;
};
#endif

//----------------------------------------------------------------------------
bool cmSystemTools::ChangeRPath(std::string const& file,
                                std::string const& oldRPath,
                                std::string const& newRPath,
                                std::string* emsg,
                                bool* changed)
{
#if defined(CMAKE_USE_ELF_PARSER)
  if(changed)
    {
    *changed = false;
    }
  int rp_count = 0;
  cmSystemToolsRPathInfo rp[2];
  {
  // Parse the ELF binary.
  cmELF elf(file.c_str());

  // Get the RPATH and RUNPATH entries from it.
  int se_count = 0;
  cmELF::StringEntry const* se[2] = {0, 0};
  const char* se_name[2] = {0, 0};
  if(cmELF::StringEntry const* se_rpath = elf.GetRPath())
    {
    se[se_count] = se_rpath;
    se_name[se_count] = "RPATH";
    ++se_count;
    }
  if(cmELF::StringEntry const* se_runpath = elf.GetRunPath())
    {
    se[se_count] = se_runpath;
    se_name[se_count] = "RUNPATH";
    ++se_count;
    }
  if(se_count == 0)
    {
    if(newRPath.empty())
      {
      // The new rpath is empty and there is no rpath anyway so it is
      // okay.
      return true;
      }
    else
      {
      if(emsg)
        {
        *emsg = "No valid ELF RPATH or RUNPATH entry exists in the file; ";
        *emsg += elf.GetErrorMessage();
        }
      return false;
      }
    }

  for(int i=0; i < se_count; ++i)
    {
    // If both RPATH and RUNPATH refer to the same string literal it
    // needs to be changed only once.
    if(rp_count && rp[0].Position == se[i]->Position)
      {
      continue;
      }

    // Make sure the current rpath contains the old rpath.
    std::string::size_type pos =
      cmSystemToolsFindRPath(se[i]->Value, oldRPath);
    if(pos == std::string::npos)
      {
      // If it contains the new rpath instead then it is okay.
      if(cmSystemToolsFindRPath(se[i]->Value, newRPath) != std::string::npos)
        {
        continue;
        }
      if(emsg)
        {
        std::ostringstream e;
        e << "The current " << se_name[i] << " is:\n"
          << "  " << se[i]->Value << "\n"
          << "which does not contain:\n"
          << "  " << oldRPath << "\n"
          << "as was expected.";
        *emsg = e.str();
        }
      return false;
      }

    // Store information about the entry in the file.
    rp[rp_count].Position = se[i]->Position;
    rp[rp_count].Size = se[i]->Size;
    rp[rp_count].Name = se_name[i];

    // Construct the new value which preserves the part of the path
    // not being changed.
    rp[rp_count].Value = se[i]->Value.substr(0, pos);
    rp[rp_count].Value += newRPath;
    rp[rp_count].Value += se[i]->Value.substr(pos+oldRPath.length(),
                                              oldRPath.npos);

    // Make sure there is enough room to store the new rpath and at
    // least one null terminator.
    if(rp[rp_count].Size < rp[rp_count].Value.length()+1)
      {
      if(emsg)
        {
        *emsg = "The replacement path is too long for the ";
        *emsg += se_name[i];
        *emsg += " entry.";
        }
      return false;
      }

    // This entry is ready for update.
    ++rp_count;
    }
  }

  // If no runtime path needs to be changed, we are done.
  if(rp_count == 0)
    {
    return true;
    }

  {
  // Open the file for update.
  cmsys::ofstream f(file.c_str(),
                  std::ios::in | std::ios::out | std::ios::binary);
  if(!f)
    {
    if(emsg)
      {
      *emsg = "Error opening file for update.";
      }
    return false;
    }

  // Store the new RPATH and RUNPATH strings.
  for(int i=0; i < rp_count; ++i)
    {
    // Seek to the RPATH position.
    if(!f.seekp(rp[i].Position))
      {
      if(emsg)
        {
        *emsg = "Error seeking to ";
        *emsg += rp[i].Name;
        *emsg += " position.";
        }
      return false;
      }

    // Write the new rpath.  Follow it with enough null terminators to
    // fill the string table entry.
    f << rp[i].Value;
    for(unsigned long j=rp[i].Value.length(); j < rp[i].Size; ++j)
      {
      f << '\0';
      }

    // Make sure it wrote correctly.
    if(!f)
      {
      if(emsg)
        {
        *emsg = "Error writing the new ";
        *emsg += rp[i].Name;
        *emsg += " string to the file.";
        }
      return false;
      }
    }
  }

  // Everything was updated successfully.
  if(changed)
    {
    *changed = true;
    }
  return true;
#else
  (void)file;
  (void)oldRPath;
  (void)newRPath;
  (void)emsg;
  (void)changed;
  return false;
#endif
}

//----------------------------------------------------------------------------
bool cmSystemTools::VersionCompare(cmSystemTools::CompareOp op,
                                   const char* lhss, const char* rhss)
{
  const char *endl = lhss;
  const char *endr = rhss;
  unsigned long lhs, rhs;

  while (((*endl >= '0') && (*endl <= '9')) ||
         ((*endr >= '0') && (*endr <= '9')))
    {
    // Do component-wise comparison.
    lhs = strtoul(endl, const_cast<char**>(&endl), 10);
    rhs = strtoul(endr, const_cast<char**>(&endr), 10);

    if(lhs < rhs)
      {
      // lhs < rhs, so true if operation is LESS
      return op == cmSystemTools::OP_LESS;
      }
    else if(lhs > rhs)
      {
      // lhs > rhs, so true if operation is GREATER
      return op == cmSystemTools::OP_GREATER;
      }

    if (*endr == '.')
      {
      endr++;
      }

    if (*endl == '.')
      {
      endl++;
      }
    }
  // lhs == rhs, so true if operation is EQUAL
  return op == cmSystemTools::OP_EQUAL;
}

//----------------------------------------------------------------------------
bool cmSystemTools::RemoveRPath(std::string const& file, std::string* emsg,
                                bool* removed)
{
#if defined(CMAKE_USE_ELF_PARSER)
  if(removed)
    {
    *removed = false;
    }
  int zeroCount = 0;
  unsigned long zeroPosition[2] = {0,0};
  unsigned long zeroSize[2] = {0,0};
  unsigned long bytesBegin = 0;
  std::vector<char> bytes;
  {
  // Parse the ELF binary.
  cmELF elf(file.c_str());

  // Get the RPATH and RUNPATH entries from it and sort them by index
  // in the dynamic section header.
  int se_count = 0;
  cmELF::StringEntry const* se[2] = {0, 0};
  if(cmELF::StringEntry const* se_rpath = elf.GetRPath())
    {
    se[se_count++] = se_rpath;
    }
  if(cmELF::StringEntry const* se_runpath = elf.GetRunPath())
    {
    se[se_count++] = se_runpath;
    }
  if(se_count == 0)
    {
    // There is no RPATH or RUNPATH anyway.
    return true;
    }
  if(se_count == 2 && se[1]->IndexInSection < se[0]->IndexInSection)
    {
    std::swap(se[0], se[1]);
    }

  // Get the size of the dynamic section header.
  unsigned int count = elf.GetDynamicEntryCount();
  if(count == 0)
    {
    // This should happen only for invalid ELF files where a DT_NULL
    // appears before the end of the table.
    if(emsg)
      {
      *emsg = "DYNAMIC section contains a DT_NULL before the end.";
      }
    return false;
    }

  // Save information about the string entries to be zeroed.
  zeroCount = se_count;
  for(int i=0; i < se_count; ++i)
    {
    zeroPosition[i] = se[i]->Position;
    zeroSize[i] = se[i]->Size;
    }

  // Get the range of file positions corresponding to each entry and
  // the rest of the table after them.
  unsigned long entryBegin[3] = {0,0,0};
  unsigned long entryEnd[2] = {0,0};
  for(int i=0; i < se_count; ++i)
    {
    entryBegin[i] = elf.GetDynamicEntryPosition(se[i]->IndexInSection);
    entryEnd[i] = elf.GetDynamicEntryPosition(se[i]->IndexInSection+1);
    }
  entryBegin[se_count] = elf.GetDynamicEntryPosition(count);

  // The data are to be written over the old table entries starting at
  // the first one being removed.
  bytesBegin = entryBegin[0];
  unsigned long bytesEnd = entryBegin[se_count];

  // Allocate a buffer to hold the part of the file to be written.
  // Initialize it with zeros.
  bytes.resize(bytesEnd - bytesBegin, 0);

  // Read the part of the DYNAMIC section header that will move.
  // The remainder of the buffer will be left with zeros which
  // represent a DT_NULL entry.
  char* data = &bytes[0];
  for(int i=0; i < se_count; ++i)
    {
    // Read data between the entries being removed.
    unsigned long sz = entryBegin[i+1] - entryEnd[i];
    if(sz > 0 && !elf.ReadBytes(entryEnd[i], sz, data))
      {
      if(emsg)
        {
        *emsg = "Failed to read DYNAMIC section header.";
        }
      return false;
      }
    data += sz;
    }
  }

  // Open the file for update.
  cmsys::ofstream f(file.c_str(),
                  std::ios::in | std::ios::out | std::ios::binary);
  if(!f)
    {
    if(emsg)
      {
      *emsg = "Error opening file for update.";
      }
    return false;
    }

  // Write the new DYNAMIC table header.
  if(!f.seekp(bytesBegin))
    {
    if(emsg)
      {
      *emsg = "Error seeking to DYNAMIC table header for RPATH.";
      }
    return false;
    }
  if(!f.write(&bytes[0], bytes.size()))
    {
    if(emsg)
      {
      *emsg = "Error replacing DYNAMIC table header.";
      }
    return false;
    }

  // Fill the RPATH and RUNPATH strings with zero bytes.
  for(int i=0; i < zeroCount; ++i)
    {
    if(!f.seekp(zeroPosition[i]))
      {
      if(emsg)
        {
        *emsg = "Error seeking to RPATH position.";
        }
      return false;
      }
    for(unsigned long j=0; j < zeroSize[i]; ++j)
      {
      f << '\0';
      }
    if(!f)
      {
      if(emsg)
        {
        *emsg = "Error writing the empty rpath string to the file.";
        }
      return false;
      }
    }

  // Everything was updated successfully.
  if(removed)
    {
    *removed = true;
    }
  return true;
#else
  (void)file;
  (void)emsg;
  (void)removed;
  return false;
#endif
}

//----------------------------------------------------------------------------
bool cmSystemTools::CheckRPath(std::string const& file,
                               std::string const& newRPath)
{
#if defined(CMAKE_USE_ELF_PARSER)
  // Parse the ELF binary.
  cmELF elf(file.c_str());

  // Get the RPATH or RUNPATH entry from it.
  cmELF::StringEntry const* se = elf.GetRPath();
  if(!se)
    {
    se = elf.GetRunPath();
    }

  // Make sure the current rpath contains the new rpath.
  if(newRPath.empty())
    {
    if(!se)
      {
      return true;
      }
    }
  else
    {
    if(se &&
       cmSystemToolsFindRPath(se->Value, newRPath) != std::string::npos)
      {
      return true;
      }
    }
  return false;
#else
  (void)file;
  (void)newRPath;
  return false;
#endif
}

//----------------------------------------------------------------------------
bool cmSystemTools::RepeatedRemoveDirectory(const char* dir)
{
  // Windows sometimes locks files temporarily so try a few times.
  for(int i = 0; i < 10; ++i)
    {
    if(cmSystemTools::RemoveADirectory(dir))
      {
      return true;
      }
    cmSystemTools::Delay(100);
    }
  return false;
}

//----------------------------------------------------------------------------
std::vector<std::string> cmSystemTools::tokenize(const std::string& str,
                                  const std::string& sep)
{
  std::vector<std::string> tokens;
  std::string::size_type tokend = 0;

  do
    {
    std::string::size_type tokstart=str.find_first_not_of(sep, tokend);
    if (tokstart==std::string::npos)
      {
      break;    // no more tokens
      }
    tokend=str.find_first_of(sep,tokstart);
    if (tokend==std::string::npos)
      {
      tokens.push_back(str.substr(tokstart));
      }
    else
      {
      tokens.push_back(str.substr(tokstart,tokend-tokstart));
      }
    } while (tokend!=std::string::npos);

  if (tokens.empty())
    {
    tokens.push_back("");
    }
  return tokens;
}

//----------------------------------------------------------------------------
bool cmSystemTools::StringToLong(const char* str, long* value)
{
  errno = 0;
  char *endp;
  *value = strtol(str, &endp, 10);
  return (*endp == '\0') && (endp != str) && (errno == 0);
}
