[PATCH 02/18] mingw: implement `stat()` with symlink support

From: Karsten Blees via GitGitGadget <gitgitgadget@gmail.com>
Date: Dec 17, 2025, 14:08 UTC
Message-ID: <c36848eda76742f7a7c203868a077b790301344f.1765980535.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.2018.git.1765980535.gitgitgadget@gmail.com>

From: Karsten Blees <blees@dcon.de>

With respect to symlinks, the current `mingw_stat()` implementation is almost identical to `mingw_lstat()`: except for the file type (`st_mode & S_IFMT`), it returns information about the link rather than the target.

Implement `mingw_stat()` by opening the file handle requesting minimal permissions, and then calling `GetFileInformationByHandle()` on it. This way, all links are resolved by the Windows file system layer.

If symlinks are disabled, use `mingw_lstat()` as before, but fail with `ELOOP` if a symlink would have to be resolved.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/mingw.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/compat/mingw.c b/compat/mingw.c
index f5a0fe3325..59afd69686 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1026,9 +1026,26 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 {
 	return do_lstat(0, file_name, buf);
 }
+
 int mingw_stat(const char *file_name, struct stat *buf)
 {
-	return do_lstat(1, file_name, buf);
+	wchar_t wfile_name[MAX_PATH];
+	HANDLE hnd;
+	int result;
+
+	/* open the file and let Windows resolve the links */
+	if (xutftowcs_path(wfile_name, file_name) < 0)
+		return -1;
+	hnd = CreateFileW(wfile_name, 0,
+			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+	if (hnd == INVALID_HANDLE_VALUE) {
+		errno = err_win_to_posix(GetLastError());
+		return -1;
+	}
+	result = get_file_info_by_handle(hnd, buf);
+	CloseHandle(hnd);
+	return result;
 }
 
 int mingw_fstat(int fd, struct stat *buf)

-- 
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