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) 1996-2006, PostgreSQL Global Development Group
   8  *
   9  * $PostgreSQL: pgsql/src/port/open.c,v 1.13 2006/06/25 00:18:24 momjian Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14 #ifdef WIN32
  15
  16 #include "c.h"
  17
  18 #include <windows.h>
  19 #include <fcntl.h>
  20 #include <assert.h>
  21
  22 int                     pgwin32_open(const char *fileName, int fileFlags,...);
  23
  24 static int
  25 openFlagsToCreateFileFlags(int openFlags)
  26 {
  27         switch (openFlags & (O_CREAT | O_TRUNC | O_EXCL))
  28         {
  29                 case 0:
  30                 case O_EXCL:
  31                         return OPEN_EXISTING;
  32
  33                 case O_CREAT:
  34                         return OPEN_ALWAYS;
  35
  36                 case O_TRUNC:
  37                 case O_TRUNC | O_EXCL:
  38                         return TRUNCATE_EXISTING;
  39
  40                 case O_CREAT | O_TRUNC:
  41                         return CREATE_ALWAYS;
  42
  43                 case O_CREAT | O_EXCL:
  44                 case O_CREAT | O_TRUNC | O_EXCL:
  45                         return CREATE_NEW;
  46         }
  47
  48         /* will never get here */
  49         return 0;
  50 }
  51
  52 /*
  53  *       - file attribute setting, based on fileMode?
  54  *       - handle other flags? (eg FILE_FLAG_NO_BUFFERING/FILE_FLAG_WRITE_THROUGH)
  55  */
  56 int
  57 pgwin32_open(const char *fileName, int fileFlags,...)
  58 {
  59         int                     fd;
  60         HANDLE          h;
  61         SECURITY_ATTRIBUTES sa;
  62
  63         /* Check that we can handle the request */
  64         assert((fileFlags & ((O_RDONLY | O_WRONLY | O_RDWR) | O_APPEND |
  65                                                  (O_RANDOM | O_SEQUENTIAL | O_TEMPORARY) |
  66                                                  _O_SHORT_LIVED | O_DSYNC |
  67                   (O_CREAT | O_TRUNC | O_EXCL) | (O_TEXT | O_BINARY))) == fileFlags);
  68
  69         sa.nLength = sizeof(sa);
  70         sa.bInheritHandle = TRUE;
  71         sa.lpSecurityDescriptor = NULL;
  72
  73         if ((h = CreateFile(fileName,
  74         /* cannot use O_RDONLY, as it == 0 */
  75                                           (fileFlags & O_RDWR) ? (GENERIC_WRITE | GENERIC_READ) :
  76                                          ((fileFlags & O_WRONLY) ? GENERIC_WRITE : GENERIC_READ),
  77         /* These flags allow concurrent rename/unlink */
  78                                         (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE),
  79                                                 &sa,
  80                                                 openFlagsToCreateFileFlags(fileFlags),
  81                                                 FILE_ATTRIBUTE_NORMAL |
  82                                          ((fileFlags & O_RANDOM) ? FILE_FLAG_RANDOM_ACCESS : 0) |
  83                            ((fileFlags & O_SEQUENTIAL) ? FILE_FLAG_SEQUENTIAL_SCAN : 0) |
  84                           ((fileFlags & _O_SHORT_LIVED) ? FILE_ATTRIBUTE_TEMPORARY : 0) |
  85                                 ((fileFlags & O_TEMPORARY) ? FILE_FLAG_DELETE_ON_CLOSE : 0) |
  86                                                 ((fileFlags & O_DSYNC) ? FILE_FLAG_WRITE_THROUGH : 0),
  87                                                 NULL)) == INVALID_HANDLE_VALUE)
  88         {
  89                 switch (GetLastError())
  90                 {
  91                                 /* EMFILE, ENFILE should not occur from CreateFile. */
  92                         case ERROR_PATH_NOT_FOUND:
  93                         case ERROR_FILE_NOT_FOUND:
  94                                 errno = ENOENT;
  95                                 break;
  96                         case ERROR_FILE_EXISTS:
  97                                 errno = EEXIST;
  98                                 break;
  99                         case ERROR_ACCESS_DENIED:
 100                                 errno = EACCES;
 101                                 break;
 102                         default:
 103                                 errno = EINVAL;
 104                 }
 105                 return -1;
 106         }
 107
 108         /* _open_osfhandle will, on error, set errno accordingly */
 109         if ((fd = _open_osfhandle((long) h, fileFlags & O_APPEND)) < 0 ||
 110                 (fileFlags & (O_TEXT | O_BINARY) && (_setmode(fd, fileFlags & (O_TEXT | O_BINARY)) < 0)))
 111                 CloseHandle(h);                 /* will not affect errno */
 112         return fd;
 113 }
 114
 115 #endif