src/support/fs_extras.C

   1 // -*- C++ -*-
   2
   3 #include <config.h>
   4
   5 #include "fs_extras.h"
   6
   7 #include <boost/filesystem/config.hpp>
   8 #include <boost/filesystem/exception.hpp>
   9 #include <boost/detail/workaround.hpp>
  10 #include <boost/throw_exception.hpp>
  11
  12 #include <sys/types.h>
  13 #include <sys/stat.h>
  14 #include <fcntl.h>
  15
  16 // BOOST_POSIX or BOOST_WINDOWS specify which API to use.
  17 # if !defined( BOOST_WINDOWS ) && !defined( BOOST_POSIX )
  18 #   if defined(_WIN32) || defined(__WIN32__) || defined(WIN32) || defined(__CYGWIN__)
  19 #     define BOOST_WINDOWS
  20 #   else
  21 #     define BOOST_POSIX
  22 #   endif
  23 # endif
  24
  25 namespace fs = boost::filesystem;
  26
  27 namespace boost {
  28 namespace filesystem {
  29
  30 bool is_readable(path const & ph)
  31 {
  32 #ifdef BOOST_POSIX
  33         return ::access(ph.string().c_str(), R_OK) == 0;
  34 #endif
  35 #ifdef BOOST_WINDOWS
  36         DWORD const attr = ::GetFileAttributes(ph.string().c_str());
  37         return attr != INVALID_FILE_ATTRIBUTES &&
  38                 (attr & FILE_ATTRIBUTE_DIRECTORY) != FILE_ATTRIBUTE_DIRECTORY;
  39 #endif
  40 }
  41
  42
  43 bool is_writable(path const & ph)
  44 {
  45 #ifdef BOOST_POSIX
  46         return ::access(ph.string().c_str(), W_OK) == 0;
  47 #endif
  48 #ifdef BOOST_WINDOWS
  49         DWORD const attr = ::GetFileAttributes(ph.string().c_str());
  50         if (attr != INVALID_FILE_ATTRIBUTES &&
  51             (attr & FILE_ATTRIBUTE_READONLY) != 0) {
  52                 // Read-only - no write access
  53                 return false;
  54         }
  55         return attr != INVALID_FILE_ATTRIBUTES &&
  56                 (attr & FILE_ATTRIBUTE_DIRECTORY) != FILE_ATTRIBUTE_DIRECTORY;
  57 #endif
  58 }
  59
  60
  61 bool is_readonly(path const & ph)
  62 {
  63 #ifdef BOOST_POSIX
  64         return is_readable(ph) && !is_writable(ph);
  65 #endif
  66 #ifdef BOOST_WINDOWS
  67         DWORD const attr = ::GetFileAttributes(ph.string().c_str());
  68         return (attr != INVALID_FILE_ATTRIBUTES
  69                 && (attr & FILE_ATTRIBUTE_READONLY));
  70 #endif
  71 }
  72
  73
  74 void copy_file(path const & source, path const & target, bool noclobber)
  75 {
  76
  77 #ifdef BOOST_POSIX
  78         int const infile = ::open(source.string().c_str(), O_RDONLY);
  79         if (infile == -1) {
  80                 boost::throw_exception(
  81                         filesystem_error(
  82                                 "boost::filesystem::copy_file",
  83                                 source, target,
  84                                 fs::detail::system_error_code()));
  85         }
  86
  87         struct stat source_stat;
  88         int const ret = ::fstat(infile, &source_stat);
  89         if (ret == -1) {
  90                 ::close(infile);
  91                 boost::throw_exception(
  92                         filesystem_error(
  93                                 "boost::filesystem::copy_file",
  94                                 source, target,
  95                                 fs::detail::system_error_code()));
  96         }
  97
  98         int const flags = O_WRONLY | O_CREAT | (noclobber ? O_EXCL : O_TRUNC);
  99
 100         int const outfile = ::open(target.string().c_str(), flags, source_stat.st_mode);
 101         if (outfile == -1) {
 102                 ::close(infile);
 103                 boost::throw_exception(
 104                         filesystem_error(
 105                                 "boost::filesystem::copy_file",
 106                                 source, target,
 107                                 fs::detail::system_error_code()));
 108         }
 109
 110         std::size_t const buf_sz = 32768;
 111         char buf[buf_sz];
 112         ssize_t in = -1;
 113         ssize_t out = -1;
 114
 115         while (true) {
 116                 in = ::read(infile, buf, buf_sz);
 117                 if (in == -1) {
 118                         break;
 119                 } else if (in == 0) {
 120                         break;
 121                 } else {
 122                         out = ::write(outfile, buf, in);
 123                         if (out == -1) {
 124                                 break;
 125                         }
 126                 }
 127         }
 128
 129         ::close(infile);
 130         ::close(outfile);
 131
 132         if (in == -1 || out == -1)
 133                 boost::throw_exception(
 134                         filesystem_error(
 135                                 "boost::filesystem::copy_file",
 136                                 source, target,
 137                                 fs::detail::system_error_code()));
 138 #endif
 139 #ifdef BOOST_WINDOWS
 140         if (::CopyFile(source.string().c_str(), target.string().c_str(), !noclobber) == 0) {
 141                 boost::throw_exception(
 142                         filesystem_error(
 143                                 "boost::filesystem::copy_file",
 144                                 source, target,
 145                                 fs::detail::system_error_code()));
 146         }
 147 #endif
 148 }
 149
 150 }
 151 }