streams/wvfile.cc

   1 /*
   2  * Worldvisions Weaver Software:
   3  *   Copyright (C) 1997-2004 Net Integration Technologies, Inc.
   4  *
   5  * A simple class to access filesystem files using WvStreams.
   6  */
   7 #include "wvfile.h"
   8 #include "wvmoniker.h"
   9
  10 WvFile::WvFile()
  11 {
  12     readable = writable = false;
  13 }
  14
  15 #ifndef _WIN32 // meaningless to do this on win32
  16 /*
  17  * The Win32 runtime library doesn't provide fcntl so we can't
  18  * set readable and writable reliably. Use the other constructor.
  19  */
  20 WvFile::WvFile(int rwfd) : WvFDStream(rwfd)
  21 {
  22     if (rwfd > -1)
  23     {
  24         /* We have to do it this way since O_RDONLY is defined as 0
  25             in linux. */
  26         mode_t xmode = fcntl(rwfd, F_GETFL);
  27         xmode = xmode & (O_RDONLY | O_WRONLY | O_RDWR);
  28         readable = (xmode == O_RDONLY) || (xmode == O_RDWR);
  29         writable = (xmode == O_WRONLY) || (xmode == O_RDWR);
  30     }
  31     else
  32         readable = writable = false;
  33 }
  34 #endif
  35
  36
  37 WvFile::WvFile(WvStringParm filename, int mode, int create_mode)
  38 {
  39 #ifdef _WIN32
  40     mode |= O_BINARY; // WvStreams users aren't expecting crlf mangling
  41 #endif
  42     open(filename, mode, create_mode);
  43 }
  44
  45
  46 static IWvStream *increator(WvStringParm s, IObject*)
  47 {
  48     return new WvFile(s, O_RDONLY, 0666);
  49 }
  50
  51 static IWvStream *outcreator(WvStringParm s, IObject*)
  52 {
  53     return new WvFile(s, O_WRONLY|O_CREAT|O_TRUNC, 0666);
  54 }
  55
  56 static IWvStream *creator(WvStringParm s, IObject*)
  57 {
  58     return new WvFile(s, O_RDWR|O_CREAT, 0666);
  59 }
  60
  61 static WvMoniker<IWvStream> reg0("infile", increator);
  62 static WvMoniker<IWvStream> reg1("outfile", outcreator);
  63 static WvMoniker<IWvStream> reg3("file", creator);
  64
  65
  66 bool WvFile::open(WvStringParm filename, int mode, int create_mode)
  67 {
  68     noerr();
  69
  70     /* We have to do it this way since O_RDONLY is defined as 0
  71        in linux. */
  72     int xmode = (mode & (O_RDONLY | O_WRONLY | O_RDWR));
  73     readable = (xmode == O_RDONLY) || (xmode == O_RDWR);
  74     writable = (xmode == O_WRONLY) || (xmode == O_RDWR);
  75
  76     // don't do the default force_select of read if we're not readable!
  77     if (!readable)
  78         undo_force_select(true, false, false);
  79
  80     close();
  81     #ifndef _WIN32
  82     int rwfd = ::open(filename, mode | O_NONBLOCK, create_mode);
  83     #else
  84     int rwfd = ::_open(filename, mode | O_NONBLOCK, create_mode);
  85     #endif
  86     if (rwfd < 0)
  87     {
  88         seterr(errno);
  89         return false;
  90     }
  91     setfd(rwfd);
  92     fcntl(rwfd, F_SETFD, 1);
  93
  94     closed = stop_read = stop_write = false;
  95     return true;
  96 }
  97
  98
  99 #ifndef _WIN32  // since win32 doesn't support fcntl
 100 bool WvFile::open(int _rwfd)
 101 {
 102     noerr();
 103     if (_rwfd < 0)
 104         return false;
 105
 106     noerr();
 107     close();
 108
 109     int mode = fcntl(_rwfd, F_GETFL);
 110     int xmode = (mode & (O_RDONLY | O_WRONLY | O_RDWR));
 111     readable = (xmode == O_RDONLY) || (xmode == O_RDWR);
 112     writable = (xmode == O_WRONLY) || (xmode == O_RDWR);
 113
 114     if (!readable)
 115         undo_force_select(true, false, false);
 116
 117     setfd(_rwfd);
 118     fcntl(_rwfd, F_SETFL, mode | O_NONBLOCK);
 119     fcntl(_rwfd, F_SETFD, 1);
 120
 121     closed = stop_read = stop_write = false;
 122     return true;
 123 }
 124 #endif
 125
 126
 127 // files not open for read are never readable; files not open for write
 128 // are never writable.
 129 void WvFile::pre_select(SelectInfo &si)
 130 {
 131     if (!readable) si.wants.readable = false;
 132     if (!writable) si.wants.writable = false;
 133
 134     WvFDStream::pre_select(si);
 135 }
 136
 137
 138 bool WvFile::post_select(SelectInfo &si)
 139 {
 140     return WvFDStream::post_select(si);
 141 }