win32: let `resolve_symlinks()` _really_ resolve symbolic links

When one tries to call `CreateFile()` with a reparse point, it will
trigger an `ERROR_INVALID_NAME` unless `FILE_FLAG_OPEN_REPARSE_POINT` is
passed. However, _when_ that flag is passed, it does not open a handle
to the symlink _target_, but to the symlink itself.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

1 files changed, 9 insertions, 1 deletions

diff --git a/win32/mingw.c b/win32/mingw.c
index e8152c87e..50ab92f0d 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -1134,9 +1134,16 @@ static char *resolve_symlinks(char *path)
         char *ptr = NULL;
         DECLARE_PROC_ADDR(DWORD, GetFinalPathNameByHandleA, HANDLE,
                                                 LPSTR, DWORD, DWORD);
+        char *resolve = NULL;
+
+        if (GetFileAttributesA(path) & FILE_ATTRIBUTE_REPARSE_POINT) {
+                resolve = xmalloc_follow_symlinks(path);
+                if (!resolve)
+                        return NULL;
+        }
 
         /* need a file handle to resolve symlinks */
-        h = CreateFileA(path, 0, 0, NULL, OPEN_EXISTING,
+        h = CreateFileA(resolve ?: path, 0, 0, NULL, OPEN_EXISTING,
                                 FILE_FLAG_BACKUP_SEMANTICS, NULL);
         if (h != INVALID_HANDLE_VALUE) {
                 if (!INIT_PROC_ADDR(kernel32.dll, GetFinalPathNameByHandleA)) {
@@ -1155,6 +1162,7 @@ static char *resolve_symlinks(char *path)
         errno = err_win_to_posix();
  end:
         CloseHandle(h);
+        free(resolve);
         return ptr;
 }