[PATCH v4 2/4] msvcrt: Translate file open access pattern hints

[Luke Deller]

Translate access pattern hints supplied to fopen / _open into the
corresponding attributes for the lower level CreateFileW call.

Signed-off-by: Luke Deller <luke at deller.id.au>
---
v4: Adjust the behaviour of fopen when both 'S' (for sequential access)
and 'R' (for random access) are supplied, so that only the first of
these is used and the second ignored, to match what Marvin the testbot
reported is the behaviour on real Windows.
---
 dlls/msvcrt/file.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/dlls/msvcrt/file.c b/dlls/msvcrt/file.c
index 6e955099090..b0eeaf2a351 100644
--- a/dlls/msvcrt/file.c
+++ b/dlls/msvcrt/file.c
@@ -22,8 +22,6 @@
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  *
- * TODO
- * Use the file flag hints O_SEQUENTIAL, O_RANDOM, O_SHORT_LIVED
  */
 
 #include <direct.h>
@@ -1609,8 +1607,12 @@ static int msvcrt_get_flags(const wchar_t* mode, int *open_flags, int* stream_fl
     case 'w':
       break;
     case 'S':
+      if (!(*open_flags & _O_RANDOM))
+          *open_flags |= _O_SEQUENTIAL;
+      break;
     case 'R':
-      FIXME("ignoring cache optimization flag: %c\n", mode[-1]);
+      if (!(*open_flags & _O_SEQUENTIAL))
+          *open_flags |= _O_RANDOM;
       break;
     default:
       ERR("incorrect mode flag: %c\n", mode[-1]);
@@ -2269,6 +2271,13 @@ int CDECL _wsopen_dispatch( const wchar_t* path, int oflags, int shflags, int pm
       sharing |= FILE_SHARE_DELETE;
   }
 
+  if (oflags & _O_RANDOM)
+      attrib |= FILE_FLAG_RANDOM_ACCESS;
+  if (oflags & _O_SEQUENTIAL)
+      attrib |= FILE_FLAG_SEQUENTIAL_SCAN;
+  if (oflags & _O_SHORT_LIVED)
+      attrib |= FILE_ATTRIBUTE_TEMPORARY;
+
   sa.nLength              = sizeof( SECURITY_ATTRIBUTES );
   sa.lpSecurityDescriptor = NULL;
   sa.bInheritHandle       = !(oflags & _O_NOINHERIT);
-- 
2.25.1