Alexandre Julliard : ntdll: Use MAP_SHARED also for read-only mappings.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: b1f8a91e6c1f9bf5524eb130a912fb8727f258ff
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=b1f8a91e6c1f9bf5524eb130a...

Author: Alexandre Julliard 
Date:   Tue Feb  6 10:43:12 2018 +0100

ntdll: Use MAP_SHARED also for read-only mappings.

This essentially reverts commit dac252ecb42fb17c2f3f2deb559262514b58e990.
It's necessary for macOS.

Signed-off-by: Alexandre Julliard

---

dlls/ntdll/virtual.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/virtual.c b/dlls/ntdll/virtual.c
index 534daf9..426af01 100644
--- a/dlls/ntdll/virtual.c
+++ b/dlls/ntdll/virtual.c
@@ -1146,7 +1146,7 @@ static NTSTATUS map_file_into_view( struct file_view *view, int fd, size_t start
 {
     void *ptr;
     int prot = VIRTUAL_GetUnixProt( vprot | VPROT_COMMITTED /* make sure it is accessible */ );
-    unsigned int flags = MAP_FIXED | ((vprot & VPROT_WRITE) ? MAP_SHARED : MAP_PRIVATE);
+    unsigned int flags = MAP_FIXED | ((vprot & VPROT_WRITECOPY) ? MAP_PRIVATE : MAP_SHARED);

assert( start < view->size );
     assert( start + size <= view->size );
@@ -1171,7 +1171,7 @@ static NTSTATUS map_file_into_view( struct file_view *view, int fd, size_t start
             break;
         case ENOEXEC:
         case ENODEV:  /* filesystem doesn't support mmap(), fall back to read() */
-            if (flags & MAP_SHARED)
+            if (vprot & VPROT_WRITE)
             {
                 ERR( "shared writable mmap not supported, broken filesystem?\n" );
                 return STATUS_NOT_SUPPORTED;