granicus.if.org Git - postgresql/blob - src/port/open.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * open.c
   4  *         Win32 open() replacement
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
   8  *
   9  * $PostgreSQL: pgsql/src/port/open.c,v 1.4 2004/08/29 05:07:02 momjian Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14 #ifdef WIN32
  15
  16 #include <windows.h>
  17 #include <fcntl.h>
  18 #include <errno.h>
  19 #include <assert.h>
  20
  21 static int
  22 openFlagsToCreateFileFlags(int openFlags)
  23 {
  24         switch (openFlags & (O_CREAT | O_TRUNC | O_EXCL))
  25         {
  26                 case 0:
  27                 case O_EXCL:
  28                         return OPEN_EXISTING;
  29
  30                 case O_CREAT:
  31                         return OPEN_ALWAYS;
  32
  33                 case O_TRUNC:
  34                 case O_TRUNC | O_EXCL:
  35                         return TRUNCATE_EXISTING;
  36
  37                 case O_CREAT | O_TRUNC:
  38                         return CREATE_ALWAYS;
  39
  40                 case O_CREAT | O_EXCL:
  41                 case O_CREAT | O_TRUNC | O_EXCL:
  42                         return CREATE_NEW;
  43         }
  44
  45         /* will never get here */
  46         return 0;
  47 }
  48
  49 /*
  50  *       - file attribute setting, based on fileMode?
  51  *       - handle other flags? (eg FILE_FLAG_NO_BUFFERING/FILE_FLAG_WRITE_THROUGH)
  52  */
  53 int
  54 win32_open(const char *fileName, int fileFlags,...)
  55 {
  56         int                     fd;
  57         HANDLE          h;
  58         SECURITY_ATTRIBUTES sa;
  59
  60         /* Check that we can handle the request */
  61         assert((fileFlags & ((O_RDONLY | O_WRONLY | O_RDWR) | O_APPEND |
  62                                                  (O_RANDOM | O_SEQUENTIAL | O_TEMPORARY) |
  63                                                  _O_SHORT_LIVED |
  64           (O_CREAT | O_TRUNC | O_EXCL) | (O_TEXT | O_BINARY))) == fileFlags);
  65
  66         sa.nLength = sizeof(sa);
  67         sa.bInheritHandle = TRUE;
  68         sa.lpSecurityDescriptor = NULL;
  69
  70         if ((h = CreateFile(fileName,
  71         /* cannot use O_RDONLY, as it == 0 */
  72                                   (fileFlags & O_RDWR) ? (GENERIC_WRITE | GENERIC_READ) :
  73                                  ((fileFlags & O_WRONLY) ? GENERIC_WRITE : GENERIC_READ),
  74                                 (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE),
  75                                                 &sa,
  76                                                 openFlagsToCreateFileFlags(fileFlags),
  77                                                 FILE_ATTRIBUTE_NORMAL |
  78                                  ((fileFlags & O_RANDOM) ? FILE_FLAG_RANDOM_ACCESS : 0) |
  79                    ((fileFlags & O_SEQUENTIAL) ? FILE_FLAG_SEQUENTIAL_SCAN : 0) |
  80                   ((fileFlags & _O_SHORT_LIVED) ? FILE_ATTRIBUTE_TEMPORARY : 0) |
  81                          ((fileFlags & O_TEMPORARY) ? FILE_FLAG_DELETE_ON_CLOSE : 0),
  82                                                 NULL)) == INVALID_HANDLE_VALUE)
  83         {
  84                 switch (GetLastError())
  85                 {
  86                                 /* EMFILE, ENFILE should not occur from CreateFile. */
  87                         case ERROR_PATH_NOT_FOUND:
  88                         case ERROR_FILE_NOT_FOUND:
  89                                 errno = ENOENT;
  90                                 break;
  91                         case ERROR_FILE_EXISTS:
  92                                 errno = EEXIST;
  93                                 break;
  94                         case ERROR_ACCESS_DENIED:
  95                                 errno = EACCES;
  96                                 break;
  97                         default:
  98                                 errno = EINVAL;
  99                 }
 100                 return -1;
 101         }
 102
 103         /* _open_osfhandle will, on error, set errno accordingly */
 104         if ((fd = _open_osfhandle((long) h, fileFlags & O_APPEND)) < 0 ||
 105                 (fileFlags & (O_TEXT | O_BINARY) && (_setmode(fd, fileFlags & (O_TEXT | O_BINARY)) < 0)))
 106                 CloseHandle(h);                 /* will not affect errno */
 107         return fd;
 108 }
 109
 110 #endif