Daniel Lehman : msvcrt: Don't set error in wcstombs_s_l if no characters to convert.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 417897248735cfaabb2e440147bdc0f7816fb97c
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=417897248735cfaabb2e44014...

Author: Daniel Lehman 
Date:   Mon Feb  3 12:06:10 2020 -0800

msvcrt: Don't set error in wcstombs_s_l if no characters to convert.

Signed-off-by: Daniel Lehman 
Signed-off-by: Piotr Caban 
Signed-off-by: Alexandre Julliard

---

dlls/msvcrt/tests/string.c | 2 +-
 dlls/msvcrt/wcs.c          | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/dlls/msvcrt/tests/string.c b/dlls/msvcrt/tests/string.c
index 32e264908a..7d9b46b3e6 100644
--- a/dlls/msvcrt/tests/string.c
+++ b/dlls/msvcrt/tests/string.c
@@ -2300,7 +2300,7 @@ static void test__wcstombs_s_l(void)
         { L"text",   _TRUNCATE, "",     1, 1,  STRUNCATE, NULL, FALSE, TRUE },
         { L"text",   5,         "",     3, 0,  ERANGE,    NULL, TRUE },

-        { L"",       0,         NULL,   0, 1,  0,         "English_United States.1252", TRUE, TRUE },
+        { L"",       0,         NULL,   0, 1,  0,         "English_United States.1252" },
         { L"\xfffd", 1,         NULL,   0, 0,  EILSEQ,    "English_United States.1252", TRUE },
         { L"\xfffd", 1,         "",     1, 0,  EILSEQ,    "English_United States.1252", TRUE },
         { L"\xfffd", 1,         "",     6, 0,  EILSEQ,    "English_United States.1252", TRUE },
diff --git a/dlls/msvcrt/wcs.c b/dlls/msvcrt/wcs.c
index 8411048204..64bc1f83d4 100644
--- a/dlls/msvcrt/wcs.c
+++ b/dlls/msvcrt/wcs.c
@@ -459,12 +459,12 @@ static MSVCRT_size_t MSVCRT_wcsrtombs_l(char *mbstr, const MSVCRT_wchar_t **wcst

if(!mbstr) {
         tmp = WideCharToMultiByte(locinfo->lc_codepage, WC_NO_BEST_FIT_CHARS,
-                *wcstr, -1, NULL, 0, NULL, &used_default)-1;
+                *wcstr, -1, NULL, 0, NULL, &used_default);
         if(!tmp || used_default) {
             *MSVCRT__errno() = MSVCRT_EILSEQ;
             return -1;
         }
-        return tmp;
+        return tmp-1;
     }

while(**wcstr) {