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         sys_close(handle);
 100
 101         handle = Handle();
 102         signal_closed.emit();
 103 }
 104
 105 void File::set_block(bool b)
 106 {
 107         check_access(M_NONE);
 108
 109         mode = (mode&~M_NONBLOCK);
 110         if(b)
 111                 mode = (mode|M_NONBLOCK);
 112 #ifndef WIN32
 113         int flags = fcntl(*handle, F_GETFD);
 114         fcntl(*handle, F_SETFL, (flags&O_NONBLOCK)|(b?0:O_NONBLOCK));
 115 #endif
 116 }
 117
 118 unsigned File::do_write(const char *buf, unsigned size)
 119 {
 120         check_access(M_WRITE);
 121
 122         if(size==0)
 123                 return 0;
 124
 125 #ifdef WIN32
 126         if(mode&M_APPEND)
 127                 seek(0, S_END);
 128 #endif
 129
 130         return sys_write(handle, buf, size);
 131 }
 132
 133 unsigned File::do_read(char *buf, unsigned size)
 134 {
 135         check_access(M_READ);
 136
 137         if(size==0)
 138                 return 0;
 139
 140         unsigned ret = sys_read(handle, buf, size);
 141         if(ret==0)
 142         {
 143                 eof_flag = true;
 144                 signal_end_of_file.emit();
 145         }
 146
 147         return ret;
 148 }
 149
 150 void File::sync()
 151 {
 152 #ifndef WIN32
 153         signal_flush_required.emit();
 154
 155         fsync(*handle);
 156 #endif
 157 }
 158
 159 unsigned File::seek(int off, SeekType st)
 160 {
 161         check_access(M_NONE);
 162
 163         signal_flush_required.emit();
 164
 165         int type = sys_seek_type(st);
 166 #ifdef WIN32
 167         DWORD ret = SetFilePointer(*handle, off, 0, type);
 168         if(ret==INVALID_SET_FILE_POINTER)
 169                 throw system_error("SetFilePointer");
 170 #else
 171         off_t ret = lseek(*handle, off, type);
 172         if(ret==(off_t)-1)
 173                 throw system_error("lseek");
 174 #endif
 175
 176         eof_flag = false;
 177
 178         return ret;
 179 }
 180
 181 unsigned File::tell() const
 182 {
 183         check_access(M_NONE);
 184
 185 #ifdef WIN32
 186         DWORD ret = SetFilePointer(*handle, 0, 0, FILE_CURRENT);
 187         if(ret==INVALID_SET_FILE_POINTER)
 188                 throw system_error("SetFilePointer");
 189 #else
 190         off_t ret = lseek(*handle, 0, SEEK_CUR);
 191         if(ret==(off_t)-1)
 192                 throw system_error("lseek");
 193 #endif
 194
 195         return ret;
 196 }
 197
 198 void File::check_access(Mode m) const
 199 {
 200         if(!handle || (m && !(mode&m)))
 201                 throw invalid_access(m);
 202 }
 203
 204 } // namespace IO
 205 } // namespace Msp