[PATCH 1/7] kernelbase: Better match Windows behaviour in PathCchStripToRoot().

[Paul Gofman]

From: Paul Gofman

---
 dlls/kernelbase/path.c       | 24 +++++++-----------------
 dlls/kernelbase/tests/path.c |  1 +
 2 files changed, 8 insertions(+), 17 deletions(-)

diff --git a/dlls/kernelbase/path.c b/dlls/kernelbase/path.c
index 548982e4e7e..fe4b9cd9cd3 100644
--- a/dlls/kernelbase/path.c
+++ b/dlls/kernelbase/path.c
@@ -915,29 +915,16 @@ HRESULT WINAPI PathCchStripToRoot(WCHAR *path, SIZE_T size)
 {
     const WCHAR *root_end;
     WCHAR *segment_end;
-    BOOL is_unc;

TRACE("%s %Iu\n", wine_dbgstr_w(path), size);

if (!path || !*path || !size || size > PATHCCH_MAX_CCH) return E_INVALIDARG;

-    /* \\?\UNC\* and \\* have to have at least two extra segments to be striped,
-     * e.g. \\?\UNC\a\b\c -> \\?\UNC\a\b
-     *      \\a\b\c         -> \\a\b         */
-    if ((is_unc = is_prefixed_unc(path)) || (path[0] == '\' && path[1] == '\' && path[2] != '?'))
-    {
-        root_end = is_unc ? path + 8 : path + 3;
-        if (!get_next_segment(root_end, &root_end)) return S_FALSE;
-        if (!get_next_segment(root_end, &root_end)) return S_FALSE;
-
-        if (root_end - path >= size) return E_INVALIDARG;
-
-        segment_end = path + (root_end - path) - 1;
-        *segment_end = 0;
-        return S_OK;
-    }
-    else if (PathCchSkipRoot(path, &root_end) == S_OK)
+    if (PathCchSkipRoot(path, &root_end) == S_OK)
     {
+        if (root_end && root_end > path && root_end[-1] == '\'
+            && ((is_prefixed_unc(path) && path[8]) || (path[0] == '\' && path[1] == '\' && path[2] && path[2] != '?')))
+            root_end--;
         if (root_end - path >= size) return E_INVALIDARG;

segment_end = path + (root_end - path);
@@ -947,7 +934,10 @@ HRESULT WINAPI PathCchStripToRoot(WCHAR *path, SIZE_T size)
         return S_OK;
     }
     else
+    {
+        *path = 0;
         return E_INVALIDARG;
+    }
 }

BOOL WINAPI PathIsUNCEx(const WCHAR *path, const WCHAR **server)
diff --git a/dlls/kernelbase/tests/path.c b/dlls/kernelbase/tests/path.c
index 36e00e0d9ef..59b93b3fcdd 100644
--- a/dlls/kernelbase/tests/path.c
+++ b/dlls/kernelbase/tests/path.c
@@ -2200,6 +2200,7 @@ static const struct striptoroot_test striptoroot_tests[] =
     {"\\a", "\\a", S_FALSE},
     {"\\a\b", "\\a\b", S_FALSE},
     {"\\a\b\c", "\\a\b", S_OK},
+    {"\\\", "\\", S_OK},

/* UNC */
     {"\\?\UNC\", "\\?\UNC\", S_FALSE},