Mark White : kernel32: Fix forward slash path handling to GetVolumePathNameW.

[Alexandre Julliard]

Module: wine
Branch: stable
Commit: 205291791e9f70e73238866114c1cb28c3388074
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=205291791e9f70e73238866114c1cb28c3388074

Author: Mark White <chopinbig2 at gmail.com>
Date:   Sat Mar 24 01:08:02 2018 -0400

kernel32: Fix forward slash path handling to GetVolumePathNameW.

Signed-off-by: Mark White <chopinbig2 at gmail.com>
Signed-off-by: Alexandre Julliard <julliard at winehq.org>
(cherry picked from commit d37d9860a1b598c5a32e4f42e7c5b40224a60de2)
Signed-off-by: Michael Stefaniuc <mstefani at winehq.org>

---

 dlls/kernel32/tests/volume.c | 4 ++++
 dlls/kernel32/volume.c       | 8 ++++----
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/dlls/kernel32/tests/volume.c b/dlls/kernel32/tests/volume.c
index 365e38c..c47043d 100644
--- a/dlls/kernel32/tests/volume.c
+++ b/dlls/kernel32/tests/volume.c
@@ -772,6 +772,10 @@ static void test_GetVolumePathNameA(void)
             "s:omefile", "S:\\" /* win2k, winxp */, sizeof(volume_path),
             ERROR_FILE_NOT_FOUND, NO_ERROR
         },
+        { /* test 42: a reasonable forward slash path that is guaranteed to exist */
+            "C:/windows/system32", "C:\\", sizeof(volume_path),
+            NO_ERROR, NO_ERROR
+        },
     };
     BOOL ret, success;
     DWORD error;
diff --git a/dlls/kernel32/volume.c b/dlls/kernel32/volume.c
index b4163f0..3a4edf8 100644
--- a/dlls/kernel32/volume.c
+++ b/dlls/kernel32/volume.c
@@ -1693,6 +1693,10 @@ BOOL WINAPI GetVolumePathNameW(LPCWSTR filename, LPWSTR volumepathname, DWORD bu
         return FALSE;
     }
     strcpyW( volumenameW, filename );
+
+    /* Normalize path */
+    for (c = volumenameW; *c; c++) if (*c == '/') *c = '\\';
+
     stop_pos = 0;
     /* stop searching slashes early for NT-type and nearly NT-type paths */
     if (strncmpW(ntprefixW, filename, strlenW(ntprefixW)) == 0)
@@ -1776,14 +1780,10 @@ BOOL WINAPI GetVolumePathNameW(LPCWSTR filename, LPWSTR volumepathname, DWORD bu
 
     if (last_pos + 1 <= buflen)
     {
-        WCHAR *p;
         memcpy(volumepathname, filename, last_pos * sizeof(WCHAR));
         if (last_pos + 2 <= buflen) volumepathname[last_pos++] = '\\';
         volumepathname[last_pos] = '\0';
 
-        /* Normalize path */
-        for (p = volumepathname; *p; p++) if (*p == '/') *p = '\\';
-
         /* DOS-style paths always return upper-case drive letters */
         if (volumepathname[1] == ':')
             volumepathname[0] = toupperW(volumepathname[0]);