operations.cpp

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//  operations.cpp  ----------------------------------------------------------//

//  Copyright 2002-2005 Beman Dawes
//  Copyright 2001 Dietmar Kuehl
//  Use, modification, and distribution is subject to the Boost Software
//  License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy
//  at http://www.boost.org/LICENSE_1_0.txt)

//  See library home page at http://www.boost.org/libs/filesystem

//----------------------------------------------------------------------------// 

// define BOOST_FILESYSTEM_SOURCE so that <boost/filesystem/config.hpp> knows
// the library is being built (possibly exporting rather than importing code)
#define BOOST_FILESYSTEM_SOURCE 

#define _POSIX_PTHREAD_SEMANTICS  // Sun readdir_r() needs this

// enable the XPG-compliant version of readdir_r() on AIX
#if defined(_AIX)
# define _LINUX_SOURCE_COMPAT
#endif

#if !(defined(__HP_aCC) && defined(_ILP32) && \
      !defined(_STATVFS_ACPP_PROBLEMS_FIXED))
#define _FILE_OFFSET_BITS 64 // at worst, these defines may have no effect,
#endif
#define __USE_FILE_OFFSET64 // but that is harmless on Windows and on POSIX
      // 64-bit systems or on 32-bit systems which don't have files larger 
      // than can be represented by a traditional POSIX/UNIX off_t type. 
      // OTOH, defining them should kick in 64-bit off_t's (and thus 
      // st_size) on 32-bit systems that provide the Large File
      // Support (LFS) interface, such as Linux, Solaris, and IRIX.
      // The defines are given before any headers are included to
      // ensure that they are available to all included headers.
      // That is required at least on Solaris, and possibly on other
      // systems as well.

// for some compilers (CodeWarrior, for example), windows.h
// is getting included by some other boost header, so do this early:
#if !defined(_WIN32_WINNT)
#define _WIN32_WINNT 0x0500 // Default to Windows 2K or later
#endif


#include <boost/filesystem/operations.hpp>
#include <boost/scoped_array.hpp>
#include <boost/throw_exception.hpp>
#include <boost/detail/workaround.hpp>

namespace fs = boost::filesystem;
using boost::system::error_code;
using boost::system::system_category;

# if defined(BOOST_WINDOWS_API)
#   include <windows.h>
#   if defined(__BORLANDC__) || defined(__MWERKS__)
#     if defined(__BORLANDC__)
        using std::time_t;
#     endif
#     include <utime.h>
#   else
#     include <sys/utime.h>
#   endif

# else // BOOST_POSIX_API
#   include <sys/types.h>
#   if !defined(__APPLE__) && !defined(__OpenBSD__)
#     include <sys/statvfs.h>
#     define BOOST_STATVFS statvfs
#     define BOOST_STATVFS_F_FRSIZE vfs.f_frsize
#   else
#ifdef __OpenBSD__
#     include <sys/param.h>
#endif
#     include <sys/mount.h>
#     define BOOST_STATVFS statfs
#     define BOOST_STATVFS_F_FRSIZE static_cast<boost::uintmax_t>( vfs.f_bsize )
#   endif
#   include <dirent.h>
#   include <unistd.h>
#   include <fcntl.h>
#   include <utime.h>
#   include "limits.h"
# endif

//  BOOST_FILESYSTEM_STATUS_CACHE enables file_status cache in
//  dir_itr_increment. The config tests are placed here because some of the
//  macros being tested come from dirent.h.
//
// TODO: find out what macros indicate dirent::d_type present in more libraries
# if defined(BOOST_WINDOWS_API) \
  || defined(_DIRENT_HAVE_D_TYPE) // defined by GNU C library if d_type present
#   define BOOST_FILESYSTEM_STATUS_CACHE
# endif

#include <sys/stat.h>  // even on Windows some functions use stat()
#include <string>
#include <cstring>
#include <cstdio>      // for remove, rename
#include <cerrno>
#include <cassert>
// #include <iostream>    // for debugging only; comment out when not in use

#ifdef BOOST_NO_STDC_NAMESPACE
namespace std { using ::strcmp; using ::remove; using ::rename; }
#endif

//  helpers  -----------------------------------------------------------------//

namespace
{
  const error_code ok;

  bool is_empty_directory( const std::string & dir_path )
  {
    static const fs::directory_iterator end_itr;
    return fs::directory_iterator(fs::path(dir_path)) == end_itr;
  }

#ifdef BOOST_WINDOWS_API
  
// For Windows, the xxxA form of various function names is used to avoid
// inadvertently getting wide forms of the functions. (The undecorated
// forms are actually macros, so can misfire if the user has various
// other macros defined. There was a bug report of this happening.)

  inline DWORD get_file_attributes( const char * ph )
    { return ::GetFileAttributesA( ph ); }

# ifndef BOOST_FILESYSTEM_NARROW_ONLY

  inline DWORD get_file_attributes( const wchar_t * ph )
    { return ::GetFileAttributesW( ph ); }

  bool is_empty_directory( const std::wstring & dir_path )
  {
    static const fs::wdirectory_iterator wend_itr;
    return fs::wdirectory_iterator(fs::wpath(dir_path)) == wend_itr;
  }

  inline BOOL get_file_attributes_ex( const wchar_t * ph,
    WIN32_FILE_ATTRIBUTE_DATA & fad )
  { return ::GetFileAttributesExW( ph, ::GetFileExInfoStandard, &fad ); }
      
  HANDLE create_file( const wchar_t * ph, DWORD dwDesiredAccess,
    DWORD dwShareMode, LPSECURITY_ATTRIBUTES lpSecurityAttributes,
    DWORD dwCreationDisposition, DWORD dwFlagsAndAttributes,
    HANDLE hTemplateFile )
  {
    return ::CreateFileW( ph, dwDesiredAccess, dwShareMode,
      lpSecurityAttributes, dwCreationDisposition, dwFlagsAndAttributes,
      hTemplateFile );
  }

  inline DWORD get_current_directory( DWORD sz, wchar_t * buf )
    { return ::GetCurrentDirectoryW( sz, buf ); } 

  inline bool set_current_directory( const wchar_t * buf )
    { return ::SetCurrentDirectoryW( buf ) != 0 ; } 

  inline bool get_free_disk_space( const std::wstring & ph,
    PULARGE_INTEGER avail, PULARGE_INTEGER total, PULARGE_INTEGER free )
    { return ::GetDiskFreeSpaceExW( ph.c_str(), avail, total, free ) != 0; }

  inline std::size_t get_full_path_name(
    const std::wstring & ph, std::size_t len, wchar_t * buf, wchar_t ** p )
  {
    return static_cast<std::size_t>(
      ::GetFullPathNameW( ph.c_str(),
        static_cast<DWORD>(len), buf, p ));
  } 

  inline bool remove_directory( const std::wstring & ph )
    { return ::RemoveDirectoryW( ph.c_str() ) != 0; }

  inline bool delete_file( const std::wstring & ph )
    { return ::DeleteFileW( ph.c_str() ) != 0; }

  inline bool create_directory( const std::wstring & dir )
    {  return ::CreateDirectoryW( dir.c_str(), 0 ) != 0; }

#if _WIN32_WINNT >= 0x500
  inline bool create_hard_link( const std::wstring & to_ph,
    const std::wstring & from_ph )
    {  return ::CreateHardLinkW( from_ph.c_str(), to_ph.c_str(), 0 ) != 0; }
#endif
  
# endif // ifndef BOOST_FILESYSTEM_NARROW_ONLY

  template< class String >
  fs::file_status status_template( const String & ph, error_code & ec )
  {
    DWORD attr( get_file_attributes( ph.c_str() ) );
    if ( attr == 0xFFFFFFFF )
    {
      ec = error_code( ::GetLastError(), system_category );
      if ((ec.value() == ERROR_FILE_NOT_FOUND)
        || (ec.value() == ERROR_PATH_NOT_FOUND)
        || (ec.value() == ERROR_INVALID_NAME) // "tools/jam/src/:sys:stat.h", "//foo"
        || (ec.value() == ERROR_INVALID_PARAMETER) // ":sys:stat.h"
        || (ec.value() == ERROR_BAD_PATHNAME) // "//nosuch" on Win64
        || (ec.value() == ERROR_BAD_NETPATH)) // "//nosuch" on Win32
      {
        ec = ok; // these are not considered errors;
                           // the status is considered not found
        return fs::file_status( fs::file_not_found );
      }
      else if ((ec.value() == ERROR_SHARING_VIOLATION))
      {
        ec = ok; // these are not considered errors;
                           // the file exists but the type is not known 
        return fs::file_status( fs::type_unknown );
      }
      return fs::file_status( fs::status_unknown );
    }
    ec = ok;;
    return (attr & FILE_ATTRIBUTE_DIRECTORY)
      ? fs::file_status( fs::directory_file )
      : fs::file_status( fs::regular_file );
  }

  BOOL get_file_attributes_ex( const char * ph,
    WIN32_FILE_ATTRIBUTE_DATA & fad )
  { return ::GetFileAttributesExA( ph, ::GetFileExInfoStandard, &fad ); }

  template< class String >
  boost::filesystem::detail::query_pair
  is_empty_template( const String & ph )
  {
    WIN32_FILE_ATTRIBUTE_DATA fad;
    if ( get_file_attributes_ex( ph.c_str(), fad ) == 0 )
      return std::make_pair( error_code( ::GetLastError(), system_category ), false );    
    return std::make_pair( ok,
      ( fad.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
        ? is_empty_directory( ph )
        :( !fad.nFileSizeHigh && !fad.nFileSizeLow ) );
  }

  HANDLE create_file( const char * ph, DWORD dwDesiredAccess,
    DWORD dwShareMode, LPSECURITY_ATTRIBUTES lpSecurityAttributes,
    DWORD dwCreationDisposition, DWORD dwFlagsAndAttributes,
    HANDLE hTemplateFile )
  {
    return ::CreateFileA( ph, dwDesiredAccess, dwShareMode,
      lpSecurityAttributes, dwCreationDisposition, dwFlagsAndAttributes,
      hTemplateFile );
  }

  // Thanks to Jeremy Maitin-Shepard for much help and for permission to
  // base the equivalent() implementation on portions of his 
  // file-equivalence-win32.cpp experimental code.
  struct handle_wrapper
  {
    HANDLE handle;
    handle_wrapper( HANDLE h )
      : handle(h) {}
    ~handle_wrapper()
    {
      if ( handle != INVALID_HANDLE_VALUE )
        ::CloseHandle(handle);
    }
  };

  template< class String >
  boost::filesystem::detail::query_pair
  equivalent_template( const String & ph1, const String & ph2 )
  {
    // Note well: Physical location on external media is part of the
    // equivalence criteria. If there are no open handles, physical location
    // can change due to defragmentation or other relocations. Thus handles
    // must be held open until location information for both paths has
    // been retrieved.
    handle_wrapper p1(
      create_file(
          ph1.c_str(),
          0,
          FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
          0,
          OPEN_EXISTING,
          FILE_FLAG_BACKUP_SEMANTICS,
          0 ) );
    int error1(0); // save error code in case we have to throw
    if ( p1.handle == INVALID_HANDLE_VALUE )
      error1 = ::GetLastError();
    handle_wrapper p2(
      create_file(
          ph2.c_str(),
          0,
          FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
          0,
          OPEN_EXISTING,
          FILE_FLAG_BACKUP_SEMANTICS,
          0 ) );
    if ( p1.handle == INVALID_HANDLE_VALUE
      || p2.handle == INVALID_HANDLE_VALUE )
    {
      if ( p1.handle != INVALID_HANDLE_VALUE
        || p2.handle != INVALID_HANDLE_VALUE )
        { return std::make_pair( ok, false ); }
      assert( p1.handle == INVALID_HANDLE_VALUE
        && p2.handle == INVALID_HANDLE_VALUE );
        { return std::make_pair( error_code( error1, system_category), false ); }
    }
    // at this point, both handles are known to be valid
    BY_HANDLE_FILE_INFORMATION info1, info2;
    if ( !::GetFileInformationByHandle( p1.handle, &info1 ) )
      { return std::make_pair( error_code( ::GetLastError(), system_category ), false ); }
    if ( !::GetFileInformationByHandle( p2.handle, &info2 ) )
      { return std::make_pair( error_code( ::GetLastError(), system_category ), false ); }
    // In theory, volume serial numbers are sufficient to distinguish between
    // devices, but in practice VSN's are sometimes duplicated, so last write
    // time and file size are also checked.
      return std::make_pair( ok,
        info1.dwVolumeSerialNumber == info2.dwVolumeSerialNumber
        && info1.nFileIndexHigh == info2.nFileIndexHigh
        && info1.nFileIndexLow == info2.nFileIndexLow
        && info1.nFileSizeHigh == info2.nFileSizeHigh
        && info1.nFileSizeLow == info2.nFileSizeLow
        && info1.ftLastWriteTime.dwLowDateTime
          == info2.ftLastWriteTime.dwLowDateTime
        && info1.ftLastWriteTime.dwHighDateTime
          == info2.ftLastWriteTime.dwHighDateTime );
  }

  template< class String >
  boost::filesystem::detail::uintmax_pair
  file_size_template( const String & ph )
  {
    WIN32_FILE_ATTRIBUTE_DATA fad;
    // by now, intmax_t is 64-bits on all Windows compilers
    if ( get_file_attributes_ex( ph.c_str(), fad ) == 0 )
      return std::make_pair( error_code( ::GetLastError(), system_category ), 0 );    
    if ( (fad.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) !=0 )
      return std::make_pair( error_code( ERROR_FILE_NOT_FOUND, system_category), 0 );
    return std::make_pair( ok,
      (static_cast<boost::uintmax_t>(fad.nFileSizeHigh)
        << (sizeof(fad.nFileSizeLow)*8))
      + fad.nFileSizeLow );
  }

  inline bool get_free_disk_space( const std::string & ph,