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) 1996-2003, PostgreSQL Global Development Group
   8  *
   9  * $PostgreSQL: pgsql/src/port/open.c,v 1.2 2004/04/19 17:42:59 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:    return OPEN_EXISTING;
  28
  29                 case O_CREAT:   return OPEN_ALWAYS;
  30
  31                 case O_TRUNC:
  32                 case O_TRUNC|O_EXCL:    return TRUNCATE_EXISTING;
  33
  34                 case O_CREAT|O_TRUNC:   return CREATE_ALWAYS;
  35
  36                 case O_CREAT|O_EXCL:
  37                 case O_CREAT|O_TRUNC|O_EXCL:    return CREATE_NEW;
  38         }
  39
  40         /* will never get here */
  41         return 0;
  42 }
  43
  44 /*
  45  *   - file attribute setting, based on fileMode?
  46  *   - handle other flags? (eg FILE_FLAG_NO_BUFFERING/FILE_FLAG_WRITE_THROUGH)
  47  */
  48 int win32_open(const char* fileName, int fileFlags, ...)
  49 {
  50         int fd;
  51         HANDLE h;
  52         SECURITY_ATTRIBUTES sa;
  53
  54         /* Check that we can handle the request */
  55         assert((fileFlags & ((O_RDONLY|O_WRONLY|O_RDWR) | O_APPEND      |
  56                                                  (O_RANDOM|O_SEQUENTIAL|O_TEMPORARY)    |
  57                                                  _O_SHORT_LIVED                                                 |
  58                                                  (O_CREAT|O_TRUNC|O_EXCL) | (O_TEXT|O_BINARY))) == fileFlags);
  59
  60         sa.nLength=sizeof(sa);
  61         sa.bInheritHandle=TRUE;
  62         sa.lpSecurityDescriptor=NULL;
  63
  64         if ((h = CreateFile(fileName,
  65                                                 /* cannot use O_RDONLY, as it == 0 */
  66                                                 (fileFlags & O_RDWR)     ? (GENERIC_WRITE | GENERIC_READ) :
  67                                                 ((fileFlags &  O_WRONLY) ?  GENERIC_WRITE : GENERIC_READ),
  68                                                 (FILE_SHARE_READ|FILE_SHARE_WRITE|FILE_SHARE_DELETE),
  69                                                 &sa,
  70                                                 openFlagsToCreateFileFlags(fileFlags),
  71                                                 FILE_ATTRIBUTE_NORMAL   |
  72                                                 ((fileFlags &  O_RANDOM)                ? FILE_FLAG_RANDOM_ACCESS       : 0) |
  73                                                 ((fileFlags &  O_SEQUENTIAL)    ? FILE_FLAG_SEQUENTIAL_SCAN     : 0) |
  74                                                 ((fileFlags & _O_SHORT_LIVED)   ? FILE_ATTRIBUTE_TEMPORARY      : 0) |
  75                                                 ((fileFlags &  O_TEMPORARY)             ? FILE_FLAG_DELETE_ON_CLOSE     : 0),
  76                                                 NULL)) == INVALID_HANDLE_VALUE)
  77         {
  78                 switch (GetLastError())
  79                 {
  80                         /* EMFILE, ENFILE should not occur from CreateFile. */
  81                         case ERROR_PATH_NOT_FOUND:
  82                         case ERROR_FILE_NOT_FOUND:      errno = ENOENT; break;
  83                         case ERROR_FILE_EXISTS:         errno = EEXIST; break;
  84                         case ERROR_ACCESS_DENIED:       errno = EACCES; break;
  85                         default:
  86                                 errno = EINVAL;
  87                 }
  88                 return -1;
  89         }
  90
  91         /* _open_osfhandle will, on error, set errno accordingly */
  92         if ((fd = _open_osfhandle((long)h,fileFlags&O_APPEND)) < 0 ||
  93                 (fileFlags&(O_TEXT|O_BINARY) && (_setmode(fd,fileFlags&(O_TEXT|O_BINARY)) < 0)))
  94                 CloseHandle(h); /* will not affect errno */
  95         return fd;
  96 }
  97
  98 #endif