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         close();
  90 }
  91
  92 void File::close()
  93 {
  94         if(!handle)
  95                 return;
  96
  97         signal_flush_required.emit();
  98
  99 #ifdef WIN32
 100         CloseHandle(*handle);
 101 #else
 102         ::close(*handle);
 103 #endif
 104
 105         handle = Handle();
 106         signal_closed.emit();
 107 }
 108
 109 void File::set_block(bool b)
 110 {
 111         check_access(M_NONE);
 112
 113         mode = (mode&~M_NONBLOCK);
 114         if(b)
 115                 mode = (mode|M_NONBLOCK);
 116 #ifndef WIN32
 117         int flags = fcntl(*handle, F_GETFD);
 118         fcntl(*handle, F_SETFL, (flags&O_NONBLOCK)|(b?0:O_NONBLOCK));
 119 #endif
 120 }
 121
 122 unsigned File::do_write(const char *buf, unsigned size)
 123 {
 124         check_access(M_WRITE);
 125
 126         if(size==0)
 127                 return 0;
 128
 129 #ifdef WIN32
 130         if(mode&M_APPEND)
 131                 seek(0, S_END);
 132         DWORD ret;
 133         if(WriteFile(*handle, buf, size, &ret, 0)==0)
 134                 throw system_error("WriteFile");
 135 #else
 136         int ret = ::write(*handle, buf, size);
 137         if(ret==-1)
 138         {
 139                 if(errno==EAGAIN)
 140                         return 0;
 141                 else
 142                         throw system_error("write");
 143         }
 144 #endif
 145
 146         return ret;
 147 }
 148
 149 unsigned File::do_read(char *buf, unsigned size)
 150 {
 151         check_access(M_READ);
 152
 153         if(size==0)
 154                 return 0;
 155
 156 #ifdef WIN32
 157         DWORD ret;
 158         if(ReadFile(*handle, buf, size, &ret, 0)==0)
 159                 throw system_error("ReadFile");
 160 #else
 161         int ret = ::read(*handle, buf, size);
 162         if(ret==-1)
 163         {
 164                 if(errno==EAGAIN)
 165                         return 0;
 166                 else
 167                         throw system_error("read");
 168         }
 169 #endif
 170
 171         if(ret==0)
 172         {
 173                 eof_flag = true;
 174                 signal_end_of_file.emit();
 175         }
 176
 177         return ret;
 178 }
 179
 180 void File::sync()
 181 {
 182 #ifndef WIN32
 183         signal_flush_required.emit();
 184
 185         fsync(*handle);
 186 #endif
 187 }
 188
 189 unsigned File::seek(int off, SeekType st)
 190 {
 191         check_access(M_NONE);
 192
 193         signal_flush_required.emit();
 194
 195         int type = sys_seek_type(st);
 196 #ifdef WIN32
 197         DWORD ret = SetFilePointer(*handle, off, 0, type);
 198         if(ret==INVALID_SET_FILE_POINTER)
 199                 throw system_error("SetFilePointer");
 200 #else
 201         off_t ret = lseek(*handle, off, type);
 202         if(ret==(off_t)-1)
 203                 throw system_error("lseek");
 204 #endif
 205
 206         eof_flag = false;
 207
 208         return ret;
 209 }
 210
 211 unsigned File::tell() const
 212 {
 213         check_access(M_NONE);
 214
 215 #ifdef WIN32
 216         DWORD ret = SetFilePointer(*handle, 0, 0, FILE_CURRENT);
 217         if(ret==INVALID_SET_FILE_POINTER)
 218                 throw system_error("SetFilePointer");
 219 #else
 220         off_t ret = lseek(*handle, 0, SEEK_CUR);
 221         if(ret==(off_t)-1)
 222                 throw system_error("lseek");
 223 #endif
 224
 225         return ret;
 226 }
 227
 228 void File::check_access(Mode m) const
 229 {
 230         if(!handle || (m && !(mode&m)))
 231                 throw invalid_access(m);
 232 }
 233
 234 } // namespace IO
 235 } // namespace Msp