source/io/file.cpp

   1 #ifndef WIN32
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <unistd.h>
   5 #endif
   6 #include <msp/strings/format.h>
   7 #include <msp/core/systemerror.h>
   8 #include "file.h"
   9 #include "handle_private.h"
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace IO {
  15
  16 File::File(const string &fn, Mode m, CreateMode cm)
  17 {
  18         if(!(m&M_RDWR))
  19                 throw invalid_argument("File::File mode");
  20         if(cm&~(C_CREATE|C_TRUNCATE))
  21                 throw invalid_argument("File::File create");
  22
  23         mode = m;
  24
  25 #ifdef WIN32
  26         int flags = 0;
  27         int create_flags = OPEN_EXISTING;
  28
  29         if(mode&M_READ)
  30                 flags |= GENERIC_READ;
  31         else if(mode&M_WRITE)
  32         {
  33                 flags |= GENERIC_WRITE;
  34
  35                 switch(static_cast<int>(cm))
  36                 {
  37                 case C_NONE:     create_flags = OPEN_EXISTING; break;
  38                 case C_CREATE:   create_flags = OPEN_ALWAYS; break;
  39                 case C_TRUNCATE: create_flags = TRUNCATE_EXISTING; break;
  40                 case C_CREATE+C_TRUNCATE: create_flags = CREATE_ALWAYS; break;
  41                 }
  42         }
  43
  44         *handle = CreateFile(fn.c_str(), flags, 0, 0, create_flags, FILE_ATTRIBUTE_NORMAL, 0);
  45         if(!handle)
  46         {
  47                 int err = GetLastError();
  48                 if(err==ERROR_FILE_NOT_FOUND)
  49                         throw file_not_found(fn);
  50                 else
  51                         throw system_error(format("CreateFile(%s)", fn), err);
  52         }
  53 #else
  54         int flags = 0;
  55         switch(mode&M_RDWR)
  56         {
  57         case M_READ:  flags |= O_RDONLY; break;
  58         case M_WRITE: flags |= O_WRONLY; break;
  59         case M_RDWR:  flags |= O_RDWR; break;
  60         default:;
  61         }
  62
  63         if(mode&M_WRITE)
  64         {
  65                 if(cm&C_CREATE)
  66                         flags |= O_CREAT;
  67                 if(cm&C_TRUNCATE)
  68                         flags |= O_TRUNC;
  69         }
  70         if(mode&M_APPEND)
  71                 flags |= O_APPEND;
  72         if(mode&M_NONBLOCK)
  73                 flags |= O_NONBLOCK;
  74
  75         *handle = ::open(fn.c_str(), flags, 0666);
  76         if(!handle)
  77         {
  78                 int err = errno;
  79                 if(err==ENOENT)
  80                         throw file_not_found(fn);
  81                 else
  82                         throw system_error(format("open(%s)", fn), err);
  83         }
  84 #endif
  85 }
  86
  87 File::~File()
  88 {
  89         signal_flush_required.emit();
  90         sys_close(handle);
  91         signal_closed.emit();
  92 }
  93
  94 void File::set_block(bool b)
  95 {
  96         check_access(M_NONE);
  97
  98         mode = (mode&~M_NONBLOCK);
  99         if(b)
 100                 mode = (mode|M_NONBLOCK);
 101 #ifndef WIN32
 102         int flags = fcntl(*handle, F_GETFD);
 103         fcntl(*handle, F_SETFL, (flags&O_NONBLOCK)|(b?0:O_NONBLOCK));
 104 #endif
 105 }
 106
 107 unsigned File::do_write(const char *buf, unsigned size)
 108 {
 109         check_access(M_WRITE);
 110
 111         if(size==0)
 112                 return 0;
 113
 114 #ifdef WIN32
 115         if(mode&M_APPEND)
 116                 seek(0, S_END);
 117 #endif
 118
 119         return sys_write(handle, buf, size);
 120 }
 121
 122 unsigned File::do_read(char *buf, unsigned size)
 123 {
 124         check_access(M_READ);
 125
 126         if(size==0)
 127                 return 0;
 128
 129         unsigned ret = sys_read(handle, buf, size);
 130         if(ret==0)
 131         {
 132                 eof_flag = true;
 133                 signal_end_of_file.emit();
 134         }
 135
 136         return ret;
 137 }
 138
 139 void File::sync()
 140 {
 141 #ifndef WIN32
 142         signal_flush_required.emit();
 143
 144         fsync(*handle);
 145 #endif
 146 }
 147
 148 SeekOffset File::seek(SeekOffset off, SeekType type)
 149 {
 150         check_access(M_NONE);
 151
 152         signal_flush_required.emit();
 153         off = sys_seek(handle, off, type);
 154         eof_flag = false;
 155
 156         return off;
 157 }
 158
 159 SeekOffset File::tell() const
 160 {
 161         check_access(M_NONE);
 162
 163         return sys_seek(const_cast<Handle &>(handle), 0, S_CUR);
 164 }
 165
 166 void File::check_access(Mode m) const
 167 {
 168         if(!handle || (m && !(mode&m)))
 169                 throw invalid_access(m);
 170 }
 171
 172 } // namespace IO
 173 } // namespace Msp