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 }
  36
  37
  38 bool is_writable(path const & ph)
  39 {
  40 #ifdef BOOST_POSIX
  41         return ::access(ph.string().c_str(), W_OK) == 0;
  42 #endif
  43 }
  44
  45
  46 bool is_readonly(path const & ph)
  47 {
  48 #ifdef BOOST_POSIX
  49         return is_readable(ph) && !is_writable(ph);
  50 #endif
  51 }
  52
  53
  54 void copy_file(path const & source, path const & target, bool noclobber)
  55 {
  56
  57 #ifdef BOOST_POSIX
  58         int const infile = ::open(source.string().c_str(), O_RDONLY);
  59         if (infile == -1) {
  60                 boost::throw_exception(
  61                         filesystem_error(
  62                                 "boost::filesystem::copy_file",
  63                                 source, target,
  64                                 fs::detail::system_error_code()));
  65         }
  66
  67         struct stat source_stat;
  68         int const ret = ::fstat(infile, &source_stat);
  69         if (ret == -1) {
  70                 ::close(infile);
  71                 boost::throw_exception(
  72                         filesystem_error(
  73                                 "boost::filesystem::copy_file",
  74                                 source, target,
  75                                 fs::detail::system_error_code()));
  76         }
  77
  78         int const flags = O_WRONLY | O_CREAT | (noclobber ? O_EXCL : O_TRUNC);
  79
  80         int const outfile = ::open(target.string().c_str(), flags, source_stat.st_mode);
  81         if (outfile == -1) {
  82                 ::close(infile);
  83                 boost::throw_exception(
  84                         filesystem_error(
  85                                 "boost::filesystem::copy_file",
  86                                 source, target,
  87                                 fs::detail::system_error_code()));
  88         }
  89
  90         std::size_t const buf_sz = 32768;
  91         char buf[buf_sz];
  92         ssize_t in = -1;
  93         ssize_t out = -1;
  94
  95         while (true) {
  96                 in = ::read(infile, buf, buf_sz);
  97                 if (in == -1) {
  98                         break;
  99                 } else if (in == 0) {
 100                         break;
 101                 } else {
 102                         out = ::write(outfile, buf, in);
 103                         if (out == -1) {
 104                                 break;
 105                         }
 106                 }
 107         }
 108
 109         ::close(infile);
 110         ::close(outfile);
 111
 112         if (in == -1 || out == -1)
 113                 boost::throw_exception(
 114                         filesystem_error(
 115                                 "boost::filesystem::copy_file",
 116                                 source, target,
 117                                 fs::detail::system_error_code()));
 118 #endif
 119 }
 120
 121
 122 }
 123 }