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 1.16 2006/10/03 20:44:18 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
  23 static int
  24 openFlagsToCreateFileFlags(int openFlags)
  25 {
  26         switch (openFlags & (O_CREAT | O_TRUNC | O_EXCL))
  27         {
  28                 case 0:
  29                 case O_EXCL:
  30                         return OPEN_EXISTING;
  31
  32                 case O_CREAT:
  33                         return OPEN_ALWAYS;
  34
  35                 case O_TRUNC:
  36                 case O_TRUNC | O_EXCL:
  37                         return TRUNCATE_EXISTING;
  38
  39                 case O_CREAT | O_TRUNC:
  40                         return CREATE_ALWAYS;
  41
  42                 case O_CREAT | O_EXCL:
  43                 case O_CREAT | O_TRUNC | O_EXCL:
  44                         return CREATE_NEW;
  45         }
  46
  47         /* will never get here */
  48         return 0;
  49 }
  50
  51 /*
  52  *       - file attribute setting, based on fileMode?
  53  *       - handle other flags? (eg FILE_FLAG_NO_BUFFERING/FILE_FLAG_WRITE_THROUGH)
  54  */
  55 int
  56 pgwin32_open(const char *fileName, int fileFlags,...)
  57 {
  58         int                     fd;
  59         HANDLE          h;
  60         SECURITY_ATTRIBUTES sa;
  61
  62         /* Check that we can handle the request */
  63         assert((fileFlags & ((O_RDONLY | O_WRONLY | O_RDWR) | O_APPEND |
  64                                                  (O_RANDOM | O_SEQUENTIAL | O_TEMPORARY) |
  65                                                  _O_SHORT_LIVED | O_DSYNC |
  66                   (O_CREAT | O_TRUNC | O_EXCL) | (O_TEXT | O_BINARY))) == fileFlags);
  67
  68         sa.nLength = sizeof(sa);
  69         sa.bInheritHandle = TRUE;
  70         sa.lpSecurityDescriptor = NULL;
  71
  72         if ((h = CreateFile(fileName,
  73         /* cannot use O_RDONLY, as it == 0 */
  74                                           (fileFlags & O_RDWR) ? (GENERIC_WRITE | GENERIC_READ) :
  75                                          ((fileFlags & O_WRONLY) ? GENERIC_WRITE : GENERIC_READ),
  76         /* These flags allow concurrent rename/unlink */
  77                                         (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE),
  78                                                 &sa,
  79                                                 openFlagsToCreateFileFlags(fileFlags),
  80                                                 FILE_ATTRIBUTE_NORMAL |
  81                                          ((fileFlags & O_RANDOM) ? FILE_FLAG_RANDOM_ACCESS : 0) |
  82                            ((fileFlags & O_SEQUENTIAL) ? FILE_FLAG_SEQUENTIAL_SCAN : 0) |
  83                           ((fileFlags & _O_SHORT_LIVED) ? FILE_ATTRIBUTE_TEMPORARY : 0) |
  84                                 ((fileFlags & O_TEMPORARY) ? FILE_FLAG_DELETE_ON_CLOSE : 0) |
  85                                                 ((fileFlags & O_DSYNC) ? FILE_FLAG_WRITE_THROUGH : 0),
  86                                                 NULL)) == INVALID_HANDLE_VALUE)
  87         {
  88                 switch (GetLastError())
  89                 {
  90                                 /* EMFILE, ENFILE should not occur from CreateFile. */
  91                         case ERROR_PATH_NOT_FOUND:
  92                         case ERROR_FILE_NOT_FOUND:
  93                                 errno = ENOENT;
  94                                 break;
  95                         case ERROR_FILE_EXISTS:
  96                                 errno = EEXIST;
  97                                 break;
  98                         case ERROR_ACCESS_DENIED:
  99                                 errno = EACCES;
 100                                 break;
 101                         default:
 102                                 errno = EINVAL;
 103                 }
 104                 return -1;
 105         }
 106
 107         /* _open_osfhandle will, on error, set errno accordingly */
 108         if ((fd = _open_osfhandle((long) h, fileFlags & O_APPEND)) < 0)
 109                 CloseHandle(h);                 /* will not affect errno */
 110         else if (fileFlags & (O_TEXT | O_BINARY) &&
 111                 _setmode(fd, fileFlags & (O_TEXT | O_BINARY)) < 0)
 112         {
 113                 _close(fd);
 114                 return -1;
 115         }
 116
 117         return fd;
 118 }
 119
 120 FILE *
 121 pgwin32_fopen(const char *fileName, const char *mode)
 122 {
 123         int openmode = 0;
 124         int fd;
 125
 126         if (strstr(mode, "r+"))
 127                 openmode |= O_RDWR;
 128         else if (strchr(mode, 'r'))
 129                 openmode |= O_RDONLY;
 130         if (strstr(mode, "w+"))
 131                 openmode |= O_RDWR | O_CREAT | O_TRUNC;
 132         else if (strchr(mode, 'w'))
 133                 openmode |= O_WRONLY | O_CREAT | O_TRUNC;
 134         if (strchr(mode, 'a'))
 135                 openmode |= O_WRONLY | O_CREAT | O_APPEND;
 136
 137         if (strchr(mode, 'b'))
 138                 openmode |= O_BINARY;
 139         if (strchr(mode, 't'))
 140                 openmode |= O_TEXT;
 141
 142         fd = pgwin32_open(fileName, openmode);
 143         if (fd == -1)
 144                 return NULL;
 145         return _fdopen(fd, mode);
 146 }
 147
 148 #endif