Michał Janiszewski : msvcrt: Update size checks for secure scanf versions.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 08d98f0ff83d664fa08208fed19cb90140e2ff10
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=08d98f0ff83d664fa08208fed...

Author: Michał Janiszewski <janisozaur(a)gmail.com>
Date:   Mon Jul  9 14:45:28 2018 +0200

msvcrt: Update size checks for secure scanf versions.

Signed-off-by: Michał Janiszewski <janisozaur(a)gmail.com>
Signed-off-by: Piotr Caban <piotr(a)codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard(a)winehq.org>

---

 dlls/msvcrt/scanf.h       | 4 ++--
 dlls/msvcrt/tests/scanf.c | 9 ++++++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/dlls/msvcrt/scanf.h b/dlls/msvcrt/scanf.h
index 734fe8b..0903d69 100644
--- a/dlls/msvcrt/scanf.h
+++ b/dlls/msvcrt/scanf.h
@@ -548,13 +548,13 @@ _FUNCTION_ {
                     while (width && (nch != _EOF_))
                     {
                         if (!suppress) {
-                            *str++ = _CHAR2SUPPORTED_(nch);
                             if(size) size--;
                             else {
                                 _UNLOCK_FILE_(file);
                                 *pstr = 0;
                                 return rd;
                             }
+                            *str++ = _CHAR2SUPPORTED_(nch);
                         }
                         st++;
                         width--;
@@ -574,13 +574,13 @@ _FUNCTION_ {
                     while (width && (nch != _EOF_))
                     {
                         if (!suppress) {
-                            *str++ = _WIDE2SUPPORTED_(nch);
                             if(size) size--;
                             else {
                                 _UNLOCK_FILE_(file);
                                 *pstr = 0;
                                 return rd;
                             }
+                            *str++ = _WIDE2SUPPORTED_(nch);
                         }
                         st++;
                         width--;
diff --git a/dlls/msvcrt/tests/scanf.c b/dlls/msvcrt/tests/scanf.c
index 359b079..b724483 100644
--- a/dlls/msvcrt/tests/scanf.c
+++ b/dlls/msvcrt/tests/scanf.c
@@ -282,10 +282,17 @@ static void test_sscanf_s(void)
     ok(ret == 0, "Wrong number of arguments read: %d\n", ret);
     ok(buf[0]=='\0', "buf = %s\n", buf);
 
-    buf[0] = 'a';
+    memset(buf, 'a', sizeof(buf));
     ret = psscanf_s("123", "%3c", buf, 2);
     ok(ret == 0, "Wrong number of arguments read: %d\n", ret);
     ok(buf[0]=='\0', "buf = %s\n", buf);
+    ok(buf[1]=='2', "buf[1] = %d\n", buf[1]);
+    ok(buf[2]=='a', "buf[2] = %d\n", buf[2]);
+
+    buf[3] = 'a';
+    buf[4] = 0;
+    ret = psscanf_s("123", "%3c", buf, 3);
+    ok(!strcmp("123a", buf), "buf = %s\n", buf);
 
     i = 1;
     ret = psscanf_s("123 123", "%s %d", buf, 2, &i);